U.S. patent application number 16/530750 was filed with the patent office on 2020-02-27 for delivery of therapeutic agent.
This patent application is currently assigned to Codiak BioSciences, Inc.. The applicant listed for this patent is Codiak BioSciences, Inc.. Invention is credited to Jan LOTVALL, Jonas Andrej NILSSON.
Application Number | 20200063138 16/530750 |
Document ID | / |
Family ID | 49582755 |
Filed Date | 2020-02-27 |
United States Patent
Application |
20200063138 |
Kind Code |
A1 |
LOTVALL; Jan ; et
al. |
February 27, 2020 |
DELIVERY OF THERAPEUTIC AGENT
Abstract
A method of producing nanovesicles comprising an oligonucleotide
inhibitor to an oncogene or a proto-oncogene or the gene product
thereof, said method comprises a) introducing a DNA sequence
encoding an oligonucleotide capable of inhibiting a human oncogenic
or proto-oncogenic transcription factor, into a mammalian cell; b)
allowing the cell to express said inhibitor oligonucleotide; and c)
obtaining nanovesicles containing said inhibitor oligonucleotide
from said cell. Nanovesicles produced by the claimed method can be
effectively and specifically targeted to e.g. cancer cells to
deliver the inhibitor oligonucleotide.
Inventors: |
LOTVALL; Jan; (MoInlycke,
SE) ; NILSSON; Jonas Andrej; (Kallered, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Codiak BioSciences, Inc. |
Cambridge |
MA |
US |
|
|
Assignee: |
Codiak BioSciences, Inc.
Cambridge
MA
|
Family ID: |
49582755 |
Appl. No.: |
16/530750 |
Filed: |
August 2, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15824793 |
Nov 28, 2017 |
10370663 |
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16530750 |
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14442578 |
May 13, 2015 |
9856477 |
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PCT/EP2013/073740 |
Nov 13, 2013 |
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15824793 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61P 1/04 20180101; C12N
15/111 20130101; A61P 13/12 20180101; A61P 1/16 20180101; C12N
2310/14 20130101; A61P 15/00 20180101; A61P 17/00 20180101; C12N
15/85 20130101; A61P 43/00 20180101; A61P 11/02 20180101; A61P
35/00 20180101; C12N 2320/32 20130101; C12N 2320/30 20130101; A61P
13/08 20180101; A61P 25/00 20180101; C12N 15/1135 20130101; A61P
11/00 20180101; A61P 35/02 20180101; A61P 21/00 20180101 |
International
Class: |
C12N 15/113 20060101
C12N015/113; C12N 15/11 20060101 C12N015/11; C12N 15/85 20060101
C12N015/85 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 13, 2012 |
SE |
1251290-1 |
Claims
1. A method of producing nanovesicles comprising an inhibitor
oligonucleotide to an oncogene or a proto-oncogene or the gene
product thereof, the method comprising a) introducing a DNA
sequence encoding an oligonucleotide capable of inhibiting a human
oncogenic or proto-oncogenic transcription factor into a mammalian
cell; b) maintaining the cell under conditions allowing the cell to
express the inhibitor oligonucleotide; and c) obtaining
nanovesicles containing the inhibitor oligonucleotide from the
cell.
2. The method according to claim 1, wherein the inhibitor
oligonucleotide is an inhibitor to a human MYC gene or gene product
thereof.
3. The method according to claim 1, wherein the inhibitor
oligonucleotide is an RNAi molecule.
4. (canceled)
5. The method according to claim 1, wherein the cell expresses a
targeting molecule on the cell surface.
6. The method according to claim 1, wherein the method comprises,
prior to step a) or simultaneously with step a), introducing into
the cell a DNA sequence coding for a targeting molecule to be
expressed on the cell surface.
7. The method according to claim 5, wherein the targeting molecule
is a ligand specifically binding to a surface protein that is
overexpressed on cancer cells.
8. The method according to claim 7, wherein the targeting molecule
is epidermal growth factor (EGF), melanocyte-stimulating hormone
(MSH) or a variable region of an antibody directed against a
surface protein that is overexpressed on cancer cells, or a
fab-fragment of the antibody.
9. The method according to claim 1, wherein the cell is a human
cell.
10-11. (canceled)
12. The method according to claim 1, performed in vitro or ex
vivo.
13. An isolated nanovesicle produced by the method according to
claim 1.
14. An isolated nanovesicle comprising an inhibitor oligonucleotide
to a human oncogenic or proto-oncogenic transcription factor.
15. The isolated nanovesicle according to claim 14, wherein the
oncogenic or proto-oncogenic transcription factor is a member of a
MYC gene or gene products family.
16. The isolated nanovesicle according to claim 14, wherein the
oncogene or proto-oncogene is a member of an E2F gene or gene
products family.
17. The isolated nanovesicle according to claim 14, wherein the
oligonucleotide is an RNAi molecule.
18. The isolated nanovesicle according to claim_17, wherein the
RNAi molecule is shRNA or siRNA.
19. The isolated nanovesicle according to claim 14, which is an
artificial nanovesicle produced by serial extrusions of cells
through microfilters and/or nanofilters.
20. A human cell transfected or transduced with a genetic construct
comprising a gene whose gene product functionally replaces a human
oncogenic or proto-oncogenic transcription factor naturally
expressed by human cell, wherein the human cell further contains a
DNA sequence encoding an oligonucleotide capable of inhibiting the
human oncogenic or proto-oncogenic transcription factor.
21. The human cell according to claim 20, wherein the human
oncogenic or proto-oncogenic transcription factor is encoded by one
member of a MYC gene family, and the genetic construct comprises
another member of a MYC gene family.
24. The human cell according to claim 20, which is a stem cell.
25. A composition comprising a nanovesicle according to claim 14
and a pharmaceutically acceptable carrier.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of 371 U.S. application
Ser. No. 14/442,578, filed May 13, 2015, which claims priority to
National Stage of International Application No. PCT/EP2013/073740,
filed Nov. 13, 2013, which is hereby incorporated in its entirety
by reference and which claims the benefit of Swedish application
no. 1251290-1, filed on Nov. 13, 2012, also incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention related to the delivery of potentially
therapeutic agents via cell-derived vesicles.
BACKGROUND OF THE INVENTION
[0003] Cancer is a leading cause of death worldwide. In 2008,
various cancers accounted for 7.6 million deaths (around 13% of all
deaths), according to the World Health Organization (WHO), and this
number is projected to continue rising, with an estimated 13.1
million deaths worldwide in 2030 [GLOBOCAN 2008 (IARC) Section of
Cancer Information (11/11/2012)].
[0004] Malignant melanoma is responsible for a majority of deaths
caused by skin tumors, and is the most common malignancy in young
adults. When melanoma is metastatic, prognosis is unfavorable, and
the therapeutic alternatives are few. Uveal melanoma has different
clinical features than skin melanomas, and often spreads primarily
to liver. For uveal melanoma it has been proposed that
approximately one out of two patients will develop metastases
within 15 years after treatment of the primary ocular tumor. The
average survival time after diagnosis of liver metastases is 8 to
10 months and the mortality rate in patients with liver metastases
of uveal melanoma is 92% over two years. One treatment option is
regional perfusion of the liver with hyperthermia and melphalan.
This approach is however very invasive and associated with risks of
surgical complications. Even though remissions are seen in most
cases, survival is only marginally prolonged.
[0005] Melanoma of the skin and uveal melanoma are merely two
examples of cancer, which takes the lives of millions of people
each year. Treatment of cancer is therefore one of the major
challenges facing modern medicine.
[0006] In general, current anti-cancer therapeutic strategies
include surgery, radiotherapy, cytotoxic drugs (chemotherapy) and
hormone drugs. A drawback of chemotherapeutic agents is that they
are unselective and cause adverse side effects, which effectively
limits dosage and hence also the therapeutic effect. There is a
need for improved, more selective cancer therapies.
[0007] A rare example of a medication directly targeted to a point
mutation oncogene is vemurafenib, targeting specifically the
BRAF.sup.v600E mutation common in skin melanomas, with relatively
less off-target effects compared to chemotherapy. However this
treatment only prolongs life with a few months in metastatic
melanoma, and only works in those melanomas that have this specific
mutation. A possibility would therefore be to target the downstream
signaling molecules. The downstream targets however lack enzymatic
activity, and are often impossible to treat with small molecules,
because of their tertiary structure. Further, as a small molecule
inhibitor would distribute throughout the body, it would also cause
systemic side effects in normal, healthy cells that are depending
on such downstream molecules.
[0008] Over the last decade, gene therapy has received increased
attention and it is believed that in the future gene therapy may be
applicable to many diseases, including cancer.
[0009] The most common form of gene therapy involves using DNA that
encodes a functional, therapeutic gene in order to replace a
mutated gene. Other types of gene therapy involve directly
correcting a mutation, or using DNA that encodes a therapeutic
protein drug (rather than a natural human gene) to provide
treatment. It has also been suggested that RNA interference,
referred to as RNAi, may be possible to exploit in gene therapy
against e.g. infections or cancer.
[0010] RNAi is a gene regulating mechanism occurring in many
eukaryotic cells which has been known since the late 1990's, and
which has been used primarily as a research tool to achieve gene
knockout.
[0011] However, a major challenge for the development of RNAi-based
therapeutics and other gene therapy applications is delivery of the
therapeutic agent (e.g. an RNA molecule). Viral vectors may be
efficient, but give rise to safety concerns, and can be rapidly
eliminated by a patient's immune system, reducing its impact.
[0012] The mode of delivery is particularly important when the
target is a gene or gene product that is important to the function
also of normal healthy cells. Therefore, delivering a drug in a
concentrated way to a diseased cell specifically has the potential
to reduce systemic side effects and side effects in other
cells.
[0013] Hence, one obstacle to successful targeting of genes and
proteins involved in disease, including cancer, is the development
of a safe and effective method of delivering the therapeutic agent
to the target.
SUMMARY OF THE INVENTION
[0014] It is an object of the invention to at least partly overcome
the drawbacks of the existing technologies, and to provide a means
of delivering a therapeutic agent, in particular an
oligonucleotide, to target cells.
[0015] In a first aspect, these and other objects are achieved by a
method of producing nanovesicles comprising an inhibitor
oligonucleotide to an oncogene or a proto-oncogene or the gene
product thereof, said method comprising
[0016] a) introducing a DNA sequence encoding a nucleic acid
capable of inhibiting a human oncogene or proto-oncogene or a gene
product thereof, into a mammalian cell;
[0017] b) maintaining the cell under conditions allowing expression
of said oligonucleotide inhibitor; and
[0018] c) obtaining nanovesicles containing said oligonucleotide
inhibitor from said cell.
[0019] The step of obtaining the nanovesicles may include isolation
naturally released extracellular vesicles from the cell culture,
and/or producing nanovesicles by extrusion of the cell through
micro and/or nanofilters.
[0020] As used herein, "oncogene" refers to a gene that has the
potential to cause cancer. In cancer cells, oncogenes are often
mutated or expressed at high levels (upregulated or amplified). A
"proto-oncogene" refers to a gene that can become an oncogene due
to mutations or increased expression. Examples of known
proto-oncogenes include RAS, WNT, MYC, ERK, and TRK.
[0021] As used herein, "nanovesicle" refers to a cell-derived
vesicle having a size in the nanometer range, and typically less
than 500 nm. "Cell-derived vesicles" include extracellular vesicles
or exosomes naturally released from cells, as well as vesicles
produced from cells by serial extrusion of the cells through micro
and/or nano filters, as described herein. Nanovesicles produced
from cells by serial extrusion may be referred to as "artificial
nanovesicles", however it should be noted that "artificial" in this
context only means that the nanovesicles are not naturally released
by the cells (as opposed to, for example, exosomes). Hence,
"artificial" in this context does not suggest that the nanovesicles
are synthetic; they are still cell-derived and are constituted of
the same components as the cell from which the nanovesicle
originated ("producer cell").
[0022] As used herein, "inhibit" means that the expression of a
gene resulting in a functional gene product (e.g. a protein) is
reduced, e.g. by inhibition of transcription, mRNA degradation, or
inhibition of mRNA translation into protein. In the context of the
present invention, the "inhibition" need not be complete; partial
inhibition or repression or down-regulation may also provide a
desirable effect.
[0023] As used herein, "oligonucleotide inhibitor" refers to an
oligonucleotide which is an inhibitor, i.e. is capable of
inhibiting a target molecule. It may also be referred to as an
"oligonucleotide inhibitor".
[0024] The method present invention is advantageous, in particular
compared to the use of synthetic delivery vehicles such as
synthetic liposomes, since the production of nanovesicles can
easily be scaled up by culturing more of the nanovesicle-producing
cells, and the nanovesicles could be produced in large quantities
at a suitable time-point, e.g. when the cell is expressing optimal
levels of targeting molecule. Additionally, the nanovesicles
obtained by the present invention, in particular the nanovesicles
obtained by serial extrusion of the producer cells, may contain
higher concentrations of the inhibitor oligonucleotide (higher
loading capacity), and may be easier to load with an inhibitor
oligonucleotide such as siRNA. Furthermore, various modification of
the nanovesicles, e.g. by expression of targeting molecules on the
surface, is enabled or at least greatly simplified. The method of
the invention is also cost-effective, since a nanovesicle-producing
cell culture can be scaled up by normal cell culturing, and also
frozen, which reduces waste associated with shelf-life of the
cells.
[0025] In embodiments of the invention the inhibitor
oligonucleotide is an inhibitor to a human oncogenic or
proto-oncogenic transcription factor. By targeting a transcription
factor, many different malignancies could be repressed by one
inhibitor. Preferably, the inhibitor oligonucleotide is may be an
inhibitor to a human MYC gene or gene product, preferably the c-Myc
gene or gene product, or an inhibitor to a member of the E2F gene
family or a gene product thereof. In other embodiments, the
inhibitor oligonucleotide may be an inhibitor to a human cellular
signal transduction molecule lacking enzymatic activity, for
example a member of the Ras family.
[0026] In embodiments of the invention, the oligonucleotide may be
RNA, preferably an RNAi molecule. An RNAi molecule may be selected
from the group consisting of shRNA, siRNA, miRNA, piRNA, nasiRNA or
antisense RNA, or any other molecule with RNAi capacity.
[0027] In embodiments of the invention, the DNA sequence encoding
an oligonucleotide capable of inhibiting a human oncogene or
proto-oncogene may be a DNA sequence selected from the group
consisting of SEQ ID NO: 1-92 and SEQ ID NO: 185-218, preferably
selected from the group consisting of SEQ ID NO: 1-32, SEQ ID NO:
33-67, and SEQ ID NO: 185-218, more preferably selected from among
SEQ ID NO: 1-10 and SEQ ID NO: 185-196.
[0028] In embodiments of the invention, the cell may express a
targeting molecule on the cell surface.
[0029] As used herein, "targeting molecule" means a molecule
capable of specifically binding to another molecule ("target
molecule"). Hence, a targeting molecule may be used to specifically
localize e.g. a cell or a vesicle presenting the targeting molecule
on its surface to an entity, such as a cancer cell, presenting the
target molecule.
[0030] The targeting molecule may be a ligand specifically binding
to a surface protein that is overexpressed on cancer cells.
Expression of targeting surface molecules in the
nanovesicle-producing cells may provide tissue-specific targeting
of the nanovesicles obtained from the cells. An advantage with
making the producer cell express the targeting molecule is that the
cell creates a membrane bound molecule that may be more efficient
in interacting with targeting receptors, whereas the efficacy of
liposome-engineered targeting often can fail.
[0031] Optionally, the method may comprise introducing a DNA
sequence coding for a targeting molecule to be expressed on the
cell surface, prior to step a) or simultaneously with step a).
[0032] In embodiments of the invention, the cell may express at
least two different targeting molecules, which may further increase
targeting specificity or otherwise improve the targeting of the
cells and/or the nanovesicles to cancer cells.
[0033] Examples of suitable targeting molecules include epidermal
growth factor (EGF), melanocyte-stimulating hormone (MSH) or a
variable region of an antibody directed against a surface protein
that is overexpressed on cancer cells, or a fab-fragment of said
antibody.
[0034] In embodiments of the invention, the cell is a human cell
and the oncogene or protooncogene is a human oncogene or
proto-oncogene. In such embodiments, the human cell may be
transfected or transduced with a genetic construct comprising a
gene whose gene product functionally replaces the human oncogene or
proto-oncogene naturally expressed by the human cell. For example,
the human oncogene or proto-oncogene may be one member of the MYC
gene family, and the genetic construct may comprise another member
of the MYC gene family.
[0035] In embodiment of the invention, the cell may be transfected
or transduced with a construct comprising the N-Myc or L-Myc genes
and overexpresses N-Myc or L-Myc.
[0036] In embodiments of the invention, step a) of the above method
may comprise introducing a genetic construct comprising said DNA
sequence coding for an oligonucleotide capable of inhibiting human
c-Myc, operatively linked to an inducible promoter, and step b) may
comprise inducing expression by activation of said inducible
promoter.
[0037] The method of producing nanovesicles according to the
invention may be performed in in vitro or ex vivo.
[0038] In another aspect, the invention provides an isolated
nanovesicle produced by the method described above.
[0039] As used herein, "isolated nanovesicle" refers to a
nanovesicle that has at least been separated from the producer
cell, typically separated from the producer cell culture or from a
first filtrate obtained when producing artificial nanovesicles by
serial extrusion through micro- or nanofilters as described below.
Isolated nanovesicles are typically contained in a medium or
composition, and may have been subject to one or more isolation or
purification steps to remove e.g. cell debris or other components
originating from cells, for example by centrifugation and/or
filtration.
[0040] Although the present specification recites "a nanovesicle",
it is understood that this term also encompasses a plurality of
nanovesicles.
[0041] In a further aspect, the invention provides an isolated
nanovesicle comprising an inhibitor oligonucleotide to a human
oncogene or proto-oncogene, preferably a human oncogenic or
proto-oncogenic transcription factor. In particular, the oncogene
or proto-oncogene may be a member of the MYC gene family, and more
preferably the gene encoding human c-Myc. Alternatively the
oncogene or proto-oncogene may be a member of the E2F gene family,
and more preferably a human gene encoding human E2f1, E2f2 or E2f3.
As another example of, the oncogene or proto-oncogene may be a
member of the RAS gene family, and more preferably a human gene
encoding human H-Ras, N-Ras or K-Ras.
[0042] In embodiments of the invention the inhibitor
oligonucleotide may be RNA, preferably an RNAi molecule. The RNAi
molecule may be selected from the group consisting of shRNA, siRNA,
miRNA, piRNA. nasiRNA or antisense RNA, or any other molecule with
RNAi capacity. In some embodiments, the RNA may be shRNA or siRNA
comprising a sequence selected from the group consisting of SEQ ID
NO: 93-184, preferably selected from the group consisting of SEQ ID
NO: 93-124 (targeting myc) and 125-159 (targeting E2f), for example
selected from among SEQ ID NO: 93-102 (targeting c-myc).
[0043] However the oligonucleotide may also be DNA, e.g. an
antisense oligonucleotide (ASO).
[0044] In a further aspect, the present invention provides a human
cell transfected or transduced with a genetic construct comprising
a gene whose gene product functionally replaces a human oncogene or
proto-oncogene naturally expressed by said human cell. Hence, the
producer cell may be modified to be independent on the normal,
non-pathological expression of a gene intended to be inhibited by
the inhibitor oligonucleotide. As a result, the growth and
viability of the producer cell can be unaffected by the production
of inhibitor oligonucleotide. In particular, the human oncogene or
proto-oncogene may be one member of the MYC gene family, and the
genetic construct introduced into the cells may be another member
of the MYC gene family. For example, the human oncogene or
proto-oncogene may be c-Myc and the genetic construct may comprise
a gene coding for N-Myc or L-Myc.
[0045] In embodiments of the invention, the human cell may further
comprise a DNA sequence coding for a inhibitor oligonucleotide to
said oncogene or proto-oncogene.
[0046] In a further aspect, the invention provides a human cell
transduced or transfected with a DNA sequence coding for an
inhibitor oligonucleotide to a human oncogene or proto-oncogene,
preferably a human oncogenic or proto-oncogenic transcription
factor, wherein said DNA sequence is operably linked to an
inducible promoter.
[0047] A human cell as comprising a DNA sequence coding for an
inhibitor oligonucleotide to a human oncogene or proto-oncogene may
be comprise a DNA sequence selected from the group consisting of
SEQ ID NO: 1-92 and SEQ ID NO: 185-218, preferably selected from
the group consisting of SEQ ID NO: 1-32, SEQ ID NO: 33-67, and SEQ
ID NO: 185-218, more preferably selected from among SEQ ID NO: 1-9
and SEQ ID NO: 185-196.
[0048] In embodiments of the invention, the human cell may be a
stem cell, preferably an embryonic stem cell or a mesenchymal stem
cell.
[0049] In another aspect, the invention provides a non-human
mammalian cell, transduced or transfected with a DNA sequence
coding for an inhibitor oligonucleotide to a human oncogene or
proto-oncogene.
[0050] The invention may be used for delivery of a therapeutic
agent to a cell, in vitro or in vivo, e.g. for therapy. Hence, in
another aspect the invention provides a method of delivering a
inhibitor oligonucleotide against a human oncogene or
proto-oncogene to a cell, comprising contacting said cell with a
human cell or a nanovesicle as described above.
[0051] In embodiments, a method of delivering a inhibitor
oligonucleotide against a human oncogene or proto-oncogene to a
cancer cell in vivo, comprises the steps of
[0052] a) administering to a patient having said cancer cell, a
cell transduced or transfected with a DNA sequence coding for an
inhibitor oligonucleotide to a human oncogene or proto-oncogene,
wherein said DNA sequence is operably linked to an inducible
promoter, and
[0053] b) inducing expression of the inhibitor oligonucleotide by
administration of a substance activating said inducible
promoter.
[0054] Hence, nanovesides as described herein may be used for
treatment of cancer.
[0055] In yet another aspect, the invention relates to a
composition comprising nanovesides as described herein and a
pharmaceutically acceptable carrier. The composition and/or the
nanovesides may be for use as a medicament, in particular for
treatment of cancer. The cancer to be treated may be selected from
the group consisting of malignant melanoma, colorectal cancer,
ovarian cancer, breast cancer, renal cancer, gastrointestinal
cancer, brain cancer, lung cancer, nasopharyngeal cancer,
esophageal cancer, gastric cancer, liver cancer, cervical cancer,
prostate cancer, non-Hodgkin lymphoma, Hodgkin lymphoma, nasal NK
T-cell lymphoma, sarcoma, leukemia, neuroendocrine cancers, midline
carcinomas, neuroblastoma and cancers of the head and neck.
DETAILED DESCRIPTION OF THE INVENTION
[0056] The present invention is based on the realization that
nanovesicles originating from cells, including mammalian cells, can
be used as vehicles for the delivery of potentially therapeutic
inhibitor molecules that target fundamental cellular functions,
with increased efficacy and decreased risk for adverse side
effects, compared to prior art delivery technologies.
[0057] In particular, the present inventors propose the use of
cells and/or vesicles as described herein for delivery of nucleic
acids that may selectively inhibit or repress the production of, or
functionality of, an oncogene or proto-oncogene or a corresponding
gene product, for example oncogenic or proto-oncogenic
transcription factors and/or oncogenic or proto-oncogenic signaling
molecules. The oncogene or proto-oncogene may be a non-mutated
oncogene.
[0058] One family of oncogenes or proto-oncogenes of particular
interest is the MYC gene family consisting of MYC, MYCN and MYCL.
The MYC gene family encodes three different transcription factors,
c-Myc (encoded by MYC), N-Myc (encoded by MYCN) and L-Myc (encoded
by MYCL), respectively, which regulate a wide array of genes and
cellular processes that are crucial in malignant disease. However,
the MYC gene family is also active in normal cell
proliferation.
[0059] The gene encoding c-Myc, MYC, is located on chromosome 8 in
the human genome. The Myc protein acts though binding of Enhancer
Box sequences (E-boxes) and also by recruiting histone
acetyltransferases (HATs), thus regulating the chomatin structure.
Myc is believed to regulate expression of 15% of all human
genes.
[0060] c-Myc and N-Myc are downstream of mitogenic signals such as
Wnt, Shh and EGF (via the MAPK/ERK pathway). Since these pathways
are often activated by mutation of genes like APC (Wnt-pathway),
PATCHED (Shh-pathway) and EGFR, BRAF, RAS, PTEN (EGF-pathway),
c-Myc or N-Myc is induced in cancer cells.
[0061] MYC can also be activated by chromosomal translocation to a
transcriptionally active chromosomal location, such as those of the
Immunoglobulin locus in B lymphocytes and of the T-cell receptor in
T lymphocytes. These translocation result in various hematological
malignancies such as Burkitt lymphoma or T-acute lymphocytic
leukemia.
[0062] An alternative activation of MYC family members is via
amplification, which happens in various cancers including lung
cancer (MYC, MYCN and MYCL), neuroblastoma (MYCN) and breast cancer
(MYC).
[0063] By modifying expression of other genes, Myc activation
results in numerous biological effects. The first to be discovered
was its capability to stimulate metabolism; e.g. it stimulates the
transcription of genes encoding ornithine decarboxylase and lactate
dehydrogenase. Myc also drives cell proliferation (e.g. by
upregulating cyclins, E2f transcription factors and downregulating
p21), and it plays a very important role in regulating cell growth
(upregulating ribosomal RNA and proteins), apoptosis
(downregulating Bcl-2), differentiation and stem cell
self-renewal.
[0064] Targeting the most common of the Myc proteins, c-Myc, with
small molecules has been proven exceedingly difficult because the
tertiary protein structure lacks pockets that could function as
binding sites for small inhibitory molecules. However, it has been
shown that the expression of Myc proteins can be blocked by RNAi
molecules (Wang, H., et al., c-Myc depletion inhibits proliferation
of human tumor cells at various stages of the cell cycle. Oncogene,
2008. 27(13): p. 1905-15).
[0065] One set of genes that are regulated downstream of Myc and
other cell signaling pathways is the transcriptional activators of
the E2F family. E2F1, E2F2 and E2F3A encode transcription factors
that stimulate genes involved in cell cycle progression such as
cyclin E and Cdk2, components of DNA replication (for example DNA
polymerase, replication origin-binding protein HsOrd, MCM 5 and
cdc6) and nucleotide biogenesis (thymidine kinase and dihydrofolate
reductase). The E2F family also contains transcriptional repressors
(E2f3b and E2f4-8).
[0066] E2f activators are bound by the retinoblastoma protein pRB,
encoded by the RB1 gene. When bound, E2f proteins are unable to
stimulate cell cycle progression. To stimulate cell cycle
progression, pRB is phosphorylated by cyclin-dependent kinases
Cdk2, Cdk4 and Cdk6 on multiple sites. This releases bound E2f from
pRB resulting in E2f activation. Cancer cells can exhibit elevated
E2f activities because of many reasons including loss of the RB1
gene or the CDKN2A-C genes. The latter encode Cdk inhibitors p15,
p16 and p18, collectively called Ink4 proteins, which inhibit Cdk4
and Cdk6. Other ways to activate constitutive E2f activity is by
direct gene transcription of CDK4, CCND2 and even E2F1 genes by Myc
proteins, or by Ink4-resistant mutations of Cdk4.
[0067] Targeting the most common of the E2f proteins, E2f1 , with
small molecules is difficult since it is a transcription factor and
hence lack an enzymatic active site. However, it has been shown
that the expression of E2f1 can be blocked by RNAi molecules in
melanoma, resulting in cell cycle arrest and senescence. (Verhaegen
et al. E2F1-Dependent Oncogenic Addiction of Melanoma Cells to MDM2
Oncogene. 2012 Feb. 16; 31 (7)828-841)
[0068] In embodiments of the invention, signaling molecules
targeted by the inhibitor molecule may be signaling molecules
lacking enzymatic activity. The signaling molecules targeted by the
inhibitor molecule may include signaling molecules involved in
intracellular signal transduction, e.g. regulating cell growth,
differentiation and survival, such as the Ras family of proteins,
including Kras, Hras, and Nras.
[0069] According to embodiments the present invention, nanovesicles
containing an inhibitor molecule can be produced in vitro, from
animal cells grown in vitro, typically mammalian cells such as
murine or human cells. The cells from which nanovesicles are
produced are herein referred to as "producer cells". In embodiment
of the invention, the nanovesicles may comprise exosomes and other
extracellular vesicles naturally released from cells, as well as
artificial vesicles produced by serial extrusions of cells through
micro- and/or nano-filters. In other embodiments of the invention
the nanovesicles are artificial nanovesicles, which may be produced
by serial extrusions of cells through micro- and/or nano-filters.
It is known that extruding cells through filters disintegrates the
cells, and that the cell membrane and membrane fractions reassemble
in the process. The yield of vesicles produced by such a method is
much higher than that of naturally produced exosomes.
[0070] Artificial nanovesicles used in embodiments of the present
invention may be produced by serial extrusions of producer cells,
typically mammalian cells, through micro- and/or nano-filters. The
nanovesicles may be produced by a method as described in US
2012/0177574, incorporated herein by reference, see in particular
paragraphs [0173]-[0197]. The thus artificially produced
nanovesicles retain the membrane structure of the producer cells,
such as the lipid bilayer structure and membrane proteins including
topology of the cell membrane surface molecules. Furthermore, the
nanovesicles retain the same cytoplasmic components as the producer
cell.
[0071] A nanovesicle according to embodiments of the invention may
have a size up to 500 nm, for example up to 300 nm, such as up to
250 nm or 200 nm. For example, the nanovesicles may have a size in
the range of 100-200 nm. However, in some embodiments the
nanovesicles may be smaller than 100 nm, for example at least 50 nm
or at least 80 nm.
[0072] In embodiments of the invention, exosomes and other
vesicles, e.g. microvesicles, naturally produced and released by
cells may also contain the inhibitor molecule and optionally also
express a targeting molecule on its surface.
[0073] Exosomes, microvesicles and artificial nanovesicles have
several similarities but there are also important differences
between these vesicles. Exosomes are produced through a natural
process, involving inward budding of the cell membrane and are
formed via multivesicular bodies. Exosomes are loaded with very
specific materials, including RNA, which is not a random selection
of cellular content. Furthermore, exosomes are very tight
structures, which have been shown to be difficult to load with
external siRNAs (Wahlgren et al., Nucleic Acids Res. 2012 Sep. 1 ;
40(17):e130). Microvesicles, on the other hand, seem in some
experiment to contain much less RNA than exosomes.
[0074] Artificial nanovesicles, produced by serial extrusions of
cells through micro- and nanofilters, do contain any protein on
their surface that the cell does not have, and also contains a
random selection of the cytoplasm. Therefore, overexpression of
targeting surface molecule in the cell membrane of an engineered
cell will result in the presence of that molecule on the artificial
nanovesicles. Similarly, a molecule overexpressed within the cell,
will also be present within the artificial nanovesicle in high
concentrations. Most importantly, the yield of artificial
nanovesicles is expected to be significantly higher than the yield
of exosomes or other extracellular vesicles naturally released by a
cell.
[0075] In embodiments of the invention, the inhibitor molecule
contained within the nanovesicles may be a nucleic acid, typically
an RNAi molecule such as shRNA, siRNA or miRNA, and typically shRNA
or siRNA.
[0076] RNA interference, referred to as RNAi, is a gene regulating
mechanism occurring in many eukaryotic cells. RNAi is mediated by
the Dicer enzyme, which cleaves a long double-stranded RNA molecule
(dsRNA) into shorter stands of double stranded RNA, small
interfering RNA (siRNA) The siRNA strands are separated into two
single-stranded RNA molecules, ssRNAs, and the guide strand is
incorporated into a complex called the RNA-induced silencing
complex (RISC) and may silence gene expression by complementary
binding to a mRNA molecule. The RNAi mechanism can be utilized for
selective silencing of a gene of interest by genetically engineered
expression in a cell of a small hairpin RNA molecule (shRNA),
containing a nucleotide sequence designed to silence a particular
mRNA, and which is subsequently cleaved by Dicer into siRNA.
[0077] As used herein, "RNAi molecule" typically refers to any RNA
molecule involved in an RNAi process, including for example dsRNA,
short hairpin RNA (shRNA, which may be used as a starting material
instead of the dsRNA), miRNA, siRNA, and ssRNA.
[0078] The use of inhibitor oligonucleotides, and RNAi in
particular, has many advantages over small molecule drugs. Small
molecules exhibit problems with solubility, which render them
impossible to formulate for in vivo delivery. Once formulated they
may also exhibit problems with absorption, requiring delivery via
intravenous, rather than an oral, route. The small molecule may
also be bound by serum proteins or hindered from entering e.g. a
tumor because of too high interstitial pressure, resulting in a
poor distribution. Small molecules may also be distributed
systemically, which results in a lower intra-tumoral concentration.
Small molecules may also be metabolized, leading to decreased
stability and the possible production of toxic bi-products.
Decreased steady-state levels can also be the result of excretion.
Finally, small molecules may have multiple targets and exhibit
toxicity in a living multicellular organism. Oligonucleotides, on
the other hand, are rapidly degraded into non-toxic residues.
[0079] In embodiments of the invention, the inhibitor molecule may
be an RNAi molecule that can achieve inhibition of a member of the
Myc family. In such embodiments, the inhibitor molecule may
comprise an RNA sequence selected from among SEQ ID NO: 93-124, for
example selected from SEQ ID NO: 93-102 (RNA targeting c-myc), SEQ
ID NO: 103-1 1 1 (targeting L-myc), or SEQ ID NO: 1 12-124
(targeting N-myc).
[0080] In embodiments of the invention the inhibitor molecule may
be an RNAi molecule that can achieve inhibition of a member of the
E2F family, for example E2f1 , E2f2 or E2f3. Such inhibitor
molecules may comprise an RNA sequence selected from SEQ ID NO:
125-159, for example SEQ ID NO: 125-140 (targeting E2f1), SEQ ID
NO: 141-148 (targeting E2f2), or SEQ ID NO: 149-159 (targeting
E2f3).
[0081] In yet other embodiments of the invention the inhibitor
molecule may be an RNAi molecule that can achieve inhibition of a
member of the Ras family, for example Hras, Kras or Nras. Such
inhibitor molecules may comprise an RNA sequence selected from SEQ
ID NO: 160-184, for example selected from SEQ ID NO: 160-171
(targeting Hras), SEQ ID NO: 172-177 (targeting Kras) or SEQ ID NO:
178-184 (targeting Nras).
[0082] In order to produce nanovesicles having the desired content
of inhibitor molecules, in particular RNAi molecules, such as shRNA
or siRNA, a DNA sequence coding for the inhibitor molecule may be
inserted into the producer cell using conventional genetic
engineering techniques, e.g. using a viral vector. Vectors suitable
for obtaining e.g. shRNA expression in animal, e.g. mammalian,
cells are known to a person skilled in the art, and may include
vectors based on adeno-associated viruses, adenoviruses or
retroviruses/lentiviruses.
[0083] Hence, a DNA sequence encoding the inhibitor molecule of
interest may be introduced into the producer cells, which may be
maintained under conditions allowing the expression of the DNA
sequence, i.e. production of the inhibitor molecule within the
producer cells. By introduction of a DNA sequence encoding the
inhibitor molecule, the inhibitor molecule may be expressed at high
quantities within the producer cell and localized to the cytosol.
For example, shRNA encoded by a DNA sequence is translocated by the
cellular machinery to the cytosol, where it may be processed into
siRNA. When the inhibitor molecule is expressed and present within
cytosolic compartment of the producer cell, the inhibitor molecule
will also be present in nanovesicles produced from the cells, since
the nanovesicles have the same cytosolic composition as the
producer cell. The nanovesicles produced from cells expressing a
shRNA will thus contain, for example, shRNA and/or siRNA
originating from the shRNA, typically siRNA.
[0084] Alternatively, an inhibitor molecule, such as an
oligonucleotide, can be loaded directly into isolated
nanovesicles.
[0085] In embodiments of the invention, the inhibitor molecule is
an RNAi molecule, typically shRNA or siRNA, for inhibition or
repression of a human MYC gene or gene product.
[0086] To express an RNAi molecule such as shRNA against human
c-Myc, a DNA sequence may be introduced in the producer cell
comprising a sequence selected from SEQ ID NO: 1 , SEQ ID NO: 2,
SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO:
7, SEQ ID NO: 8, and SEQ ID NO: 9; alternatively, a DNA sequence
may be introduced which is selected from the group consisting of
SEQ ID NO: 185, SEQ ID NO: 186, SEQ ID NO: 187, SEQ ID NO: 188, SEQ
ID NO: 189, SEQ ID NO: 190, SEQ ID NO: 191, SEQ ID NO: 192, SEQ ID
NO: 193, SEQ ID NO: 194, SEQ ID NO: 195, and SEQ ID NO: 196.
[0087] To express an RNAi molecule such as shRNA against human
L-Myc, a DNA sequence may be introduced in the producer cell
comprising a sequence selected from SEQ ID NO: 10, SEQ ID NO: 11,
SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 14, SEQ ID NO: 15, SEQ ID
NO: 16, SEQ ID NO: 17, SEQ ID NO: 18, and SEQ ID NO: 19.
Alternatively, a DNA sequence may be introduced which is selected
from the group consisting of SEQ ID NO: 197, SEQ ID NO: 198, SEQ ID
NO: 199, SEQ ID NO: 200, SEQ ID NO: 201, SEQ ID NO: 202, SEQ ID NO:
203, SEQ ID NO: 204, and SEQ ID NO: 205.
[0088] To express an RNAi molecule such as shRNA or siRNA against
human N-Myc, a DNA sequence may be introduced in the producer cell
comprising a sequence selected from SEQ ID NO: 20, SEQ ID NO: 21,
SEQ ID NO: 22, SEQ ID NO: 23, SEQ ID NO: 24, SEQ ID NO: 25, SEQ ID
NO: 26, SEQ ID NO: 27, SEQ ID NO: 28, SEQ ID NO: 29, SEQ ID NO: 30,
SEQ ID NO: 31, and SEQ ID NO: 32. Alternatively, a DNA sequence may
be introduced which is selected from the group consisting of SEQ ID
NO: 206, SEQ ID NO: 207, SEQ ID NO: 208, SEQ ID NO: 209, SEQ ID NO:
210, SEQ ID NO: 211, SEQ ID NO: 212, SEQ ID NO: 213, SEQ ID NO:
214, SEQ ID NO: 215, SEQ ID NO: 216, SEQ ID NO: 217, and SEQ ID NO:
218.
[0089] Lentiviral plasmids containing the DNA sequences of SEQ ID
NO: 185-218 are commercially available from Sigma Aldrich
(USA).
[0090] In embodiments of the invention, the inhibitor molecule is
an RNAi molecule, typically shRNA or siRNA, for inhibition or
repression of a human E2F gene or gene product. To express an RNAi
molecule such as shRNA against human E2f1 , a DNA sequence may be
introduced in the producer cell comprising a sequence selected from
SEQ ID NO: 33-48. To express an RNAi molecule such as shRNA against
human E2f2, a DNA sequence may be introduced in the producer cell
comprising a sequence selected from SEQ ID NO: 49-56. To express an
RNAi molecule such as shRNA against human E2f3, a DNA sequence may
be introduced in the producer cell comprising a sequence selected
from SEQ ID NO: 57-67.
[0091] In embodiments of the invention, the inhibitor molecule is
an RNAi molecule, typically shRNA or siRNA, for inhibition or
repression of a human RAS gene or gene product. To express an RNAi
molecule such as shRNA against human Hras, a DNA sequence may be
introduced in the producer cell comprising a sequence selected from
SEQ ID NO: 68-79. To express an RNAi molecule such as shRNA against
human Kras, a DNA sequence may be introduced in the producer cell
comprising a sequence selected from SEQ ID NO: 80-85. To express an
RNAi molecule such as shRNA against human Nras, a DNA sequence may
be introduced in the producer cell comprising a sequence selected
from SEQ ID NO: 86-92.
[0092] The DNA sequence coding for the inhibitor molecule is
typically under the control of a promoter. The promoter may be a
constitutive promoter or an inducible promoter.
[0093] In embodiments of the invention, for example where the
producer cells are human cells dependent of a functional human
c-Myc protein for their own proliferation, it may be preferable to
use an inducible promoter, so that expression of the inhibitor
molecule can be initiated at a suitable point in time, such as when
a desired number of producer cells or a desirable producer cell
density has been achieved. Any suitable conventional promoter may
be used, for example a doxycycline-inducible promoter.
[0094] In other embodiments, the producer cells may be independent
of the function of the target gene which the inhibitor molecule is
intended to inhibit or repress. In such embodiments, the promoter
may be a constitutive promoter or an inducible promoter. As used
herein "target gene" refers to a gene to be inhibited or repressed
by the inhibitor molecule, or while gene product is to be inhibited
or repressed by the inhibitor molecule.
[0095] For example, non-human animal cells or bacteria may be used
as producer cells for the production of nanovesicles containing an
inhibitor molecule directed to a human gene or gene product. For
instance, mouse cells may be used for production of an RNAi
molecule (and nanovesicles containing the RNAi molecule) against a
human gene, e.g. a member of the human MYC gene family, such as
human c-Myc, at least where the murine and human genes do not have
too high sequence similarity. Alternatively, producer cells of the
same species as the target gene may be used, which has been
modified to be independent on the target gene. As an example, human
cells to be used for the production of an RNAi molecule against a
first member of the MYC family may be modified to overexpress
another member of the MYC gene family, so that it is made
independent on the functionality of the first MYC member. In
particular, human cells may be genetically modified using standard
techniques to overexpress N-myc, which is normally expressed only
at low levels, which may functionally replace c-Myc and render the
cells independent of c-Myc. Hence, expression of an RNAi molecule
against human c-MYC within the same producer cells will not disrupt
cell growth and proliferation. Alternatively, the native c-Myc of a
human cell may be genetically modified, e.g. by introduction of one
or more point mutations so as to avoid complementarity with an RNAi
molecule directed against human c-Myc and thus avoid inhibition of
the c-Myc of the producer cell.
[0096] In embodiments of the invention, nanovesicles may be
produced from cells as described above, without insertion of a DNA
sequence encoding the inhibitor molecule. In such embodiments, the
inhibitor molecule may be introduced ("loaded") directly into the
isolated nanovesicles using electroporation or the like. For
example, an RNAi molecule such as siRNA may be inserted directly
into isolated nanovesicles by electroporation. Previous studies
suggest that that this approach may be efficient for delivery into
exosomes (Alvarez-Erviti, L, et al., Delivery of siRNA to the mouse
brain by systemic injection of targeted exosomes. Nat Biotechnol,
2011. 29(4): p. 341-5;).
[0097] The cells used as producer cells in the present invention
may be any eukaryotic cell that is capable of forming nanovesicles
and which is susceptible of expressing an inhibitor molecule.
Typically, the cells may be animal cell, in particular mammalian
cells, including murine and human cells. Further, the cells used as
producer cells may originate from a cell line suitable for in vitro
proliferation, modification and expression of the inhibitor
molecule, and production of the nanovesides. The cells may be stem
cells. Examples of suitable cells include human embryonic kidney
(HEK, e.g. HEK 293) cells, mesenchymal stem cells, fibroblasts
(e.g. NIH 3T3 mouse fibroblasts), or any other suitable eukaryotic
cells. Mesenchymal stem cells may be produced either from other
cells, such as embryonic cells, or by autologous means (thus from
the patient for which the therapy is intended)
[0098] In order to achieve selective delivery of the nanovesides to
a cancer cell, the nanovesides may have a targeting molecule
present on the outer surface of its membrane. Preferably, the
targeting molecule may be a molecule, e.g. a ligand, which
selectively binds to another molecule, e.g. a ligand receptor, that
is specific to the surface of cancer cells or overrepresented
(overexpressed) on the surface of cancer cells. Examples of
suitable targeting molecules include epidermal growth factor (EGF),
which binds to the EGF receptor (EGFR), and melanocyte-stimulating
hormone (MSH), which binds to the MSH receptor (MSHR; also called
melanocortin 1 receptor, MC1 R). EGFR is overexpressed on a
majority of epithelial cancer cell types, whereas MC1 R is
expressed on melanoma and cells of the melanocyte lineage.
Recently, it was shown that exosomes that overexpress EGF-like
peptides, using the transmembrane domain of platelet-derived growth
factor, can target to EGFR expressing tumors in vivo in mouse
(Ohno, S.I., et al., Systemically Injected Exosomes Targeted to
EGFR Deliver Antitumor MicroRNA to Breast Cancer Cells. Mol Ther,
2012). Targeting molecules can also include natural ligands or even
engineered antibody fragments possessing the ability to bind
cancer-specific surface antigens.
[0099] To introduce the targeting molecule into the nanovesides, a
DNA sequence comprising a DNA sequence, such as a gene, encoding
the targeting molecule may be introduced using conventional cloning
techniques, including any sequences such as a promoter etc.
necessary to achieve expression of the targeting molecule within
the cell. The targeting molecule may be a molecule that locates
naturally to the outer surface of the cell membrane. Alternatively,
the targeting molecule may be a fusion protein with a transmembrane
protein, such as a GPI-anchored protein or the
transmembrane/cytosolic domain of ICAM-1 (T/C ICAM-1).
[0100] When the targeting molecule is localized to the cell
membrane, the targeting molecule will also form part of the
nanovesicle membrane after isolation of nanovesicles as described
above. Genetic modification of a producer cell to express a
targeting molecule on the surface of the cell membrane may be
carried out before the step of introducing a DNA sequence encoding
the inhibitor molecule into the producer cell. Alternatively, in
embodiments of the invention, the DNA sequence encoding the
targeting molecule and the DNA sequence encoding the inhibitor
molecule may be introduced into the producer cell simultaneously.
Introduction of a targeting molecule on the surface of the producer
cell and hence also on its naturally occurring extracellular
vesicles, or the nanovesicles produced by serial extrusion through
membranes, may be performed also in embodiments where the producer
cells do not express the inhibitor molecules, and the nanovesicles
are isolated and subsequently used for direct introduction of an
inhibitor molecule e.g. via electroporation.
[0101] The present invention offers a means to develop successful
therapies against numerous diseases, including cancers.
Nanovesicles according to embodiments of the invention may be
administered to a patient suffering from a cancer caused at least
partly by the oncogene or proto-oncogene against which the
inhibitor molecule is directed. The nanovesicles may be
administered via intravenous injection or directly into tumors, or
into tumor-containing organs or parts of the body afflicted by
tumors, optionally as part of a pharmaceutical composition.
[0102] A pharmaceutical composition may comprise the nanovesicles
and typically also a pharmaceutically acceptable carrier. Examples
of pharmaceutical compositions suitable for injection include
sterile aqueous solutions or dispersions and sterile powders for
the extemporaneous preparation of sterile injectable solutions or
dispersions. Typically the composition is sterile. Further, the
composition may be fluid to the extent that easy syringeability
exists. Preferably, the composition is stable under the conditions
of manufacture and storage, and it is preferably preserved against
the contaminating action of microorganisms, such as bacteria and
fungi.
[0103] Administration of a pharmaceutical composition according to
embodiments of the invention may be effected via any suitable
route, for example intravenous, intradermal, intramuscular, into
brain, into spinal fluid, subcutaneous, directly into tumors or
tumor infested tissues, or limbs, or intraocular, or intranasal, or
by inhalation, or oral and/or intraperitoneal.
[0104] The nanovesicles may be internalized by cancer cells in a
way similar to exosomes and other vesicles, and hence deliver their
cargo of inhibitor molecule to the interior of a cancer cell, where
the inhibitor molecule can perform its inhibitor function, e.g. via
RNAi.
[0105] Additionally or alternatively, producer cells according to
embodiments of the invention may be administered directly to a
patient, for example directly into a tumor, without prior isolation
of nanovesicles. In such cases, the cells preferably express a
targeting molecule on the cell surface, so that they are localized
in close vicinity to cancer cells after administration.
Administration may be effected via any suitable route, for example
intravenous, intradermal, intramuscular, into brain, into spinal
fluid, subcutaneous, directly into tumors or tumor infested
tissues, or limbs, or intraocular, or intranasal, or by inhalation,
or oral and/or intraperitoneal. Further, in such cases the DNA
sequence encoding the molecule inhibitor is preferably under the
control of an inducible promoter, such as a promoter inducible by
doxycyclin. After administration of the cells, expression of the
inhibitor molecule may be induced by administration of doxycyclin
to the patient by any suitable route, e.g. orally or intravenously.
Upon expression of an RNAi molecule, the cells will be stressed and
as a result release high amounts of exosomes and other vesicles
during a short period of time, which will lead to high
concentration of RNAi containing vesicles in the vicinity of the
tumor cells, which then through natural means will take up the
vesicles, and the RNAi molecule will have its therapeutic effect
inside of the tumor cell by inhibiting crucial proto-oncogenes such
as c-Myc or other transcription factors. High and/or prolonged
expression of the inhibitor molecule in the injected cell will most
likely induce apoptosis, which can result in further release of the
molecule inhibitor from the cell via apoptotic bodies, which also
can deliver their cargo to recipient tumor cells. As a result, the
RNAi molecule will be encapsulated in naturally occurring nano- and
microvesicles in the close vicinity of tumor cells, and will
subsequently enter the cancer cells and elicit RNAi. The
encapsulation of the RNAi molecule into vesicles is important,
since the RNAi molecules would be naturally degraded if present as
free molecules in the interstitial tissue (extracellularly).
[0106] The present invention offers a therapeutic tool that could
potentially be used in the treatment of numerous cancerous
diseases. The c-Myc gene may be overexpressed in as much as 80% of
all cancers (Nilsson & Cleveland Oncogene. 2003 Dec. 8;
22(56):9007-21).
[0107] One example of a cancer that could be treated using cells or
nanovesicles according to embodiments of the present invention is
melanoma. It has previously been shown that c-Myc inhibition can be
efficient in causing senescence in a majority of malignant human
melanoma cell lines (Wang et al., 2008). Further, Myc inhibition by
systemic expression of a dominant-interfering Myc mutant in a mouse
model of Ras-induced lung adenocarcinoma, triggers rapid regression
of incipient and established lung tumors, confirming that targeting
Myc may be efficient in treatment of malignancy (Soucek, L, et al.,
Modelling Myc inhibition as a cancer therapy. Nature, 2008.
455(7213): p. 679-83). Together, these previous studies suggest
that many malignancies including melanoma are dependent on
c-Myc.
[0108] A nanovesicle according to embodiments of the invention that
a) targets malignant melanoma cells, and b) contains an RNAi
molecule that down-regulates a downstream oncogene or a crucial
transcription factor for the melanoma cells, may therefore be
possible to utilize in metastatic uveal melanoma, as well as
metastatic skin melanomas, regardless of oncogene mutation status.
The c-Myc and E2f1 genes are believed to be very suitable target
genes for such therapy, as they has been proven to be crucial in
melanoma in general. Lastly, a melanoma-targeting cell or
nanovesicle could possibly also be used as local therapy in the eye
in uveal melanoma without metastasis, or as adjuvant therapy
together with local removal of tumor, possibly avoiding
enucleation.
[0109] c-Myc has also been associated with carcinoma of the cervix,
colon, breast, lung and stomach, and the invention may thus also be
useful in therapy of such malignancies.
[0110] Hence, in addition to melanoma, cells and/or nanovesicles
targeting for example EGFR positive malignancies and containing an
inhibitor to c-Myc, can be a putative therapeutic approach for many
malignant diseases.
EXAMPLES
Example 1
Introducing Targeting Molecule on the Surface of Human Producer
Cells
[0111] Firstly, pCMV-zeo vectors expressing EGF or MSH in frame
with either a GPI-anchor protein or I-CAM1 are created and
transfected into HEK 293 cells or mesenchymal stem cells. The
transfected cells are treated with zeocin and resistant cells are
sorted based on surface expression of EGF or MSH using magnetic
beads or a cell sorter. Maintenance of the transgenic expression
may be routinely monitored with flow cytometry.
[0112] The cells expressing EGF or MSH fusion proteins may be
further used for production of nanovesicles, optionally with
expression of an inhibitor molecule.
Example 2
Production of Nanovesicles using Human Cells Modified to be
Independent of C-Mvc
[0113] A. Modification of Human Cells to become Independent on
C-Myc
[0114] A mammalian expression vector containing a murine retrovirus
receptor (mCAT-1) and an N-Myc:GFP fusion separated by an IRES (to
enable cap-independent translation) is transfected into HEK 293T
cells or mesenchymal stem cells. The cell line used may be equipped
with an ecotropic receptor for murine-specific envelope-pseudotyped
lentivirus to increase personnel safety. Further, by using a
pcDNA-neo vector for the cloning it is possible to also express a
neomycin resistance cassette.
[0115] Alternatively, instead of an N-Myc gene the expression
vector may contain an L-myc gene, if the inhibitor is directed to
c-Myc.
[0116] The vector is cloned into human cells using the Amaxa
nucleofector, or any other suitable methodology. Successfully
transduced cells are selected with neomycin and FACS sort for GFP
positive cells.
B. Introduction of a DNA Sequence Encoding an Inhibitor to a Human
Myc Protein into the Nanovesicle-Producing Cells
[0117] A lentiviral plasmid obtained from Sigma Aldrich, USA
(MISSION TRCpLKO-puro clones) having a sequence selected from the
group consisting of SEQ ID NO: 185-196 is transfected into HEK 293T
cells. When transfected into cells HIV-1 based transcripts are
generated which have been made replication-incompetent and
self-inactivating by a deletion in the 3'-long terminal repeat.
Further, the lentiviral vector is co-transfected with pCMV-dR8.2
dvpr and pHCMV-Eco (both from the Addgene plasmid depository), the
former containing a minimal vector expressing HIV-GAG and the
latter an eco-tropic envelope. The HEK 293T cells will thus produce
lentivirus that are replication-incompetent and can only infect
murine cells or cells expressing the murine retrovirus receptor
(mCAT1) as in Example 2A. Next, the HEK 293T cells are cultured and
virus-containing cell culture supernatant from the transfected
cells is used to transduce mCAT1-expressing human cells, followed
by selection with puromycin (encoded by lentivirus plasmid). Since
the mCAT1-expressing human cells depend on the N-Myc gene and not
on the human target gene, e.g. c-Myc, their growth or viability may
be unaffected by the expression of an inhibitor molecule directed
against a human target gene, e.g. human c-Myc.
C. Isolation of Nanovesicles
[0118] Isolation of nanovesicles, and or naturally occurring
extracellular vesicles, can be performed by known procedures, which
includes centrifugation steps. For example, artificial nanovesicles
may be produced as described in US 2012/0177574. Artificial
high-density vesicles, emergin from nuclear membranes can be
removed by a brief centrifugation steps. Nanovesicles expressing
the molecule that targets for example the EGF receptor may be
purified either by positive or negative selection, using either
advanced FACS sorting protocols, magnetic methods or any other
method, using antibody technology.
Example 3
Production of Nanovesicles using Human Cells (Inducible
Expression)
[0119] A. Introduction of a DNA Sequence Encoding an Inhibitor
against a Myc Protein (Inducible Expression) into Human Cells
[0120] A tetracycline (doxycycline) or IPTG-inducible expression
system is used for cloning the DNA sequence of the desired
inhibitor molecule (here a DNA sequence according to any one of SEQ
ID NO: 185-218. For example, the pLKO-TetON-puro system (Addgene)
or the pLKO_IPTG_3xLacO system (Sigma) may be used.
B. Isolation of Nanovesicles (Optional)
[0121] Isolation of nanovesicles, and or naturally occurring
extracellular vesicles, can be performed by known procedures, which
includes centrifugation steps. For example, artificial nanovesicles
may be produced as described in US 2012/0177574. Artificial
high-density vesicles, emerging from nuclear membranes can be
removed by a brief centrifugation steps. Nanovesicles expressing
the molecule that targets for example the EGF receptor may be
purified either by positive or negative selection, using either
advanced FACS sorting protocols, magnetic methods or any other
method, using antibody technology.
[0122] Alternatively, instead of isolating nanovesicles, the
inhibitor molecule may be recovered from the cell culture and used
later for direct introduction into nanovesicles e.g. using
electroporation. In such embodiments, the inhibitor molecules may
be introduced into artificially produced nanovesicles as described
above.
[0123] Alternatively, instead of using producing artificial
nanovesicles by sequential extrusion, extracellular vesicles that
are naturally released from the engineered producer cell, for
example exosomes, microvesicles or apoptotic bodies, may be
isolated from the cell culture. Such natural extracellular vesicles
will express both the targeting molecule on its surface, as well as
contain the inhibitor molecule.
Example 4
Production of Nanovesicles using Murine Cells
[0124] A. Introduction of DNA Sequence Encoding a Myc Inhibitor
into Murine Cells
[0125] A lentiviral plasmid obtained from Sigma Aldrich, USA
(MISSION TRCpLKO-puro clones) having a sequence selected from the
group consisting of SEQ ID NO: 185-218 is transfected into HEK 293T
cells. When transfected into cells HIV-1 based transcripts are
generated which have been made replication-incompetent by a
deletion in the 3'-long terminal repeat. Further, the lentiviral
vector is co-transfected with pCMV-dR8.2 dvpr and pHCMV-Eco (both
from the Addgene plasmid depository), the former containing a
minimal vector expressing HIV-GAG and the latter an eco-tropic
envelope. The HEK 293T cells will thus produce lentivirus that are
replication-incompetent and can only infect murine cells. Next, the
HEK 293T cells are cultured and virus-containing cell culture
supernatant from the transfected cells is used to transduce NIH 3T3
mouse fibroblasts, followed by selection with puromycin (encoded by
lentivirus plasmid). Since the mouse fibroblasts depend on their
native mouse gene and not on the human target gene, e.g. c-Myc,
their growth or viability may be unaffected by the expression of an
inhibitor molecule directed against a human target gene, e.g. human
c-Myc.
B. Isolation of Nanovesicles
[0126] Isolation of nanovesicles, and/or naturally occurring
extracellular vesicles, can be performed by known procedures, which
includes centrifugation steps. For example, artificial nanovesicles
may be produced as described in US 2012/0177574. Artificial
High-density vesicles, emerging from nuclear membranes can be
removed by a brief centrifugation steps. Nanovesicles expressing
the molecule that targets for example the EGF receptor may be
purified either by positive or negative selection, using either
advanced FACS sorting protocols, magnetic methods or any other
method, using antibody technology.
Sequence CWU 1
1
218121DNAArtificial Sequencec-Myc DNA target sequence 1cagttgaaac
acaaacttga a 21221DNAArtificial Sequencec-Myc DNA target sequence
2ccataatgta aactgcctca a 21321DNAArtificial Sequencec-Myc DNA
target sequence 3caggaactat gacctcgact a 21421DNAArtificial
Sequencec-Myc DNA target sequence 4gcttcaccaa caggaactat g
21521DNAArtificial Sequencec-Myc DNA target sequence 5actgaaagat
ttagccataa t 21621DNAArtificial Sequencec-Myc DNA target sequence
6ccagaggagg aacgagctaa a 21721DNAArtificial Sequencec-Myc DNA
target sequence 7tacggaactc ttgtgcgtaa g 21821DNAArtificial
Sequencec-Myc DNA target sequence 8cctgagacag atcagcaaca a
21921DNAArtificial Sequencec-Myc DNA target sequence 9atcatcatcc
aggactgtat g 211021DNAArtificial Sequencec-Myc DNA target sequence
10actcggtgca gccgtatttc t 211121DNAArtificial SequenceL-Myc DNA
target sequence 11cctgtgccac taaactacat t 211221DNAArtificial
SequenceL-Myc DNA target sequence 12cgaggacatc tggaagaaat t
211321DNAArtificial SequenceL-Myc DNA target sequence 13cattggctct
tctcaagctc t 211421DNAArtificial SequenceL-Myc DNA target sequence
14caggaactac gcctccatca t 211521DNAArtificial SequenceL-Myc DNA
target sequence 15cccaagcgac tcgggtaagg a 211621DNAArtificial
SequenceL-Myc DNA target sequence 16tggcgcttag agaggacaat a
211721DNAArtificial SequenceL-Myc DNA target sequence 17tgttggtaaa
cagtttggaa a 211821DNAArtificial SequenceL-Myc DNA target sequence
18tctccagttg gctttacttt a 211921DNAArtificial SequenceL-Myc DNA
target sequence 19gaggcttaga gatagacaat c 212021DNAArtificial
SequenceN-Myc DNA target sequence 20cagcagcagt tgctaaagaa a
212121DNAArtificial SequenceN-Myc DNA target sequence 21gcgtcgcaga
aaccacaaca t 212221DNAArtificial SequenceN-Myc DNA target sequence
22ctgagcgatt cagatgatga a 212321DNAArtificial SequenceN-Myc DNA
target sequence 23gccagtatta gactggaagt t 212421DNAArtificial
SequenceN-Myc DNA target sequence 24cggacgaaga tgacttctac t
212521DNAArtificial SequenceN-Myc DNA target sequence 25cacctccatg
acagcgctaa a 212621DNAArtificial SequenceN-Myc DNA target sequence
26cttctacccg gacgaagatg a 212721DNAArtificial SequenceN-Myc DNA
target sequence 27agacagcagc agttgctaaa g 212821DNAArtificial
SequenceN-Myc DNA target sequence 28catacctaag tactgtaata a
212921DNAArtificial SequenceN-Myc DNA target sequence 29tcggacttgc
tagacgcttc t 213021DNAArtificial SequenceN-Myc DNA target sequence
30acgtccgctc aagagtgtca t 213121DNAArtificial SequenceN-Myc DNA
target sequence 31cacggagatg ctgcttgaga a 213221DNAArtificial
SequenceN-Myc DNA target sequence 32acgtgccgga gttggtaaag a
213321DNAArtificial SequenceE2f1 DNA target sequence 33taactgcact
ttcggccctt t 213421DNAArtificial SequenceE2f1 DNA target sequence
34catccagctc attgccaaga a 213521DNAArtificial SequenceE2f1 DNA
target sequence 35taagagcaaa caaggcccga t 213621DNAArtificial
SequenceE2f1 DNA target sequence 36acctcttcga ctgtgacttt g
213720DNAArtificial SequenceE2f1 DNA target sequence 37acatcaccaa
cgtccttgag 203821DNAArtificial SequenceE2f1 DNA target sequence
38ctactcagcc tggagcaaga a 213921DNAArtificial SequenceE2f1 DNA
target sequence 39caggatggat atgagatggg a 214021DNAArtificial
SequenceE2f1 DNA target sequence 40cgctatgaga cctcactgaa t
214121DNAArtificial SequenceE2f1 DNA target sequence 41cgtggactct
tcggagaact t 214221DNAArtificial SequenceE2f1 DNA target sequence
42acctgatgaa tatctgtact a 214321DNAArtificial SequenceE2f1 DNA
target sequence 43cctgaggagt tcatcagcct t 214421DNAArtificial
SequenceE2f1 DNA target sequence 44cgctatgaga cctcactgaa t
214521DNAArtificial SequenceE2f1 DNA target sequence 45acctgatgaa
tatctgtact a 214621DNAArtificial SequenceE2f1 DNA target sequence
46caggatggat atgagatggg a 214721DNAArtificial SequenceE2f1 DNA
target sequence 47cgtggactct tcggagaact t 214821DNAArtificial
SequenceE2f1 DNA target sequence 48acctcttcga ctgtgacttt g
214921DNAArtificial SequenceE2f2 DNA target sequence 49ccactctata
agcagggcta a 215021DNAArtificial SequenceE2f2 DNA target sequence
50gcctatgtga cttaccagga t 215121DNAArtificial SequenceE2f2 DNA
target sequence 51gcagacagtg attgccgtca a 215221DNAArtificial
SequenceE2f2 DNA target sequence 52ccgagggcca agttgtgcga t
215321DNAArtificial SequenceE2f2 DNA target sequence 53cagcgatctc
ttcgactcct a 215421DNAArtificial SequenceE2f2 DNA target sequence
54tccgtgctgt tggcaacttt a 215521DNAArtificial SequenceE2f2 DNA
target sequence 55gaggacaacc tgcagatata t 215621DNAArtificial
SequenceE2f2 DNA target sequence 56gtacgggtga ggagtggata a
215721DNAArtificial SequenceE2f3 DNA target sequence 57cccgctttac
tcttcaggaa t 215821DNAArtificial SequenceE2f3 DNA target sequence
58cctcattaag aagaagtcta a 215921DNAArtificial SequenceE2f3 DNA
target sequence 59ccaaactgtt atagttgtga a 216021DNAArtificial
SequenceE2f3 DNA target sequence 60cctgactcaa tagagagcct a
216121DNAArtificial SequenceE2f3 DNA target sequence 61ccaactcagg
acatagcgat t 216221DNAArtificial SequenceE2f3 DNA target sequence
62acgcggtatg atacgtctct t 216321DNAArtificial SequenceE2f3 DNA
target sequence 63agatcctcac cacgaacact t 216421DNAArtificial
SequenceE2f3 DNA target sequence 64gacttcatgt gtagttgatt a
216521DNAArtificial SequenceE2f3 DNA target sequence 65acgaagtcca
gatagtccaa a 216621DNAArtificial SequenceE2f3 DNA target sequence
66ccaacctaga aggaccgttt g 216721DNAArtificial SequenceE2f3 DNA
target sequence 67gtctttgagg tctgctaata t 216821DNAArtificial
SequenceH-Ras DNA target sequence 68caagagtgcg ctgaccatcc a
216921DNAArtificial SequenceH-Ras DNA target sequence 69agaggattcc
taccggaagc a 217021DNAArtificial SequenceH-Ras DNA target sequence
70gaggattcct accggaagca c 217121DNAArtificial SequenceH-Ras DNA
target sequence 71aagagtgcgc tgaccatcca c 217221DNAArtificial
SequenceH-Ras DNA target sequence 72gacgtgcctg ttggacatcc t
217321DNAArtificial SequenceH-Ras DNA target sequence 73tggctgcacg
cactgtggaa t 217420DNAArtificial SequenceH-Ras DNA target sequence
74cctgttggac atcctggata 207521DNAArtificial SequenceH-Ras DNA
target sequence 75ccaggaggag tacagcgcca t 217621DNAArtificial
SequenceH-Ras DNA target sequence 76gcctgttgga catcctggat a
217721DNAArtificial SequenceH-Ras DNA target sequence 77caagagtgcg
ctgaccatcc a 217821DNAArtificial SequenceH-Ras DNA target sequence
78agaggattcc taccggaagc a 217921DNAArtificial SequenceH-Ras DNA
target sequence 79cggaagcagg tggtcattga t 218021DNAArtificial
SequenceK-ras DNA target sequence 80cagttgagac cttctaattg g
218121DNAArtificial SequenceK-ras DNA target sequence 81cctcgtttct
acacagagaa a 218221DNAArtificial SequenceK-ras DNA target sequence
82gatgccttct atacattagt t 218321DNAArtificial SequenceK-ras DNA
target sequence 83aggactctga agatgtacct a 218421DNAArtificial
SequenceK-ras DNA target sequence 84tagttggagc tggtggcgta g
218521DNAArtificial SequenceK-ras DNA target sequence 85cctacaggaa
gcaagtagta a 218621DNAArtificial SequenceN-Ras DNA target sequence
86gaaacctgtt tgttggacat a 218721DNAArtificial SequenceN-Ras DNA
target sequence 87cagtgccatg agagaccaat a 218821DNAArtificial
SequenceN-Ras DNA target sequence 88caagagttac gggattccat t
218921DNAArtificial SequenceN-Ras DNA target sequence 89cagtgccatg
agagaccaat a 219021DNAArtificial SequenceN-Ras DNA target sequence
90gaaacctgtt tgttggacat a 219121DNAArtificial SequenceN-Ras DNA
target sequence 91cgcactgaca atccagctaa t 219221DNAArtificial
SequenceN-Ras DNA target sequence 92ccatcaataa tagcaagtca t
219321RNAArtificial Sequencec-Myc RNA target sequence 93caguugaaac
acaaacuuga a 219421RNAArtificial Sequencec-Myc RNA target sequence
94ccauaaugua aacugccuca a 219521RNAArtificial Sequencec-Myc RNA
target sequence 95caggaacuau gaccucgacu a 219621RNAArtificial
Sequencec-Myc RNA target sequence 96gcuucaccaa caggaacuau g
219721RNAArtificial Sequencec-Myc RNA target sequence 97acugaaagau
uuagccauaa u 219821RNAArtificial Sequencec-Myc RNA target sequence
98ccagaggagg aacgagcuaa a 219921RNAArtificial Sequencec-Myc RNA
target sequence 99uacggaacuc uugugcguaa g 2110021RNAArtificial
Sequencec-Myc RNA target sequence 100ccugagacag aucagcaaca a
2110121RNAArtificial Sequencec-Myc RNA target sequence
101aucaucaucc aggacuguau g 2110221RNAArtificial Sequencec-Myc RNA
target sequence 102acucggugca gccguauuuc u 2110321RNAArtificial
SequenceL-Myc RNA target sequence 103ccugugccac uaaacuacau u
2110421RNAArtificial SequenceL-Myc RNA target sequence
104cgaggacauc uggaagaaau u 2110521RNAArtificial SequenceL-Myc RNA
target sequence 105cauuggcucu ucucaagcuc u 2110621RNAArtificial
SequenceL-Myc RNA target sequence 106caggaacuac gccuccauca u
2110721RNAArtificial SequenceL-Myc RNA target sequence
107cccaagcgac ucggguaagg a 2110821RNAArtificial SequenceL-Myc RNA
target sequence 108uggcgcuuag agaggacaau a 2110921RNAArtificial
SequenceL-Myc RNA target sequence 109uguugguaaa caguuuggaa a
2111021RNAArtificial SequenceL-Myc RNA target sequence
110ucuccaguug gcuuuacuuu a 2111121RNAArtificial SequenceL-Myc RNA
target sequence 111gaggcuuaga gauagacaau c 2111221RNAArtificial
SequenceN-Myc RNA target sequence 112cagcagcagu ugcuaaagaa a
2111321RNAArtificial SequenceN-Myc RNA target sequence
113gcgucgcaga aaccacaaca u 2111421RNAArtificial SequenceN-Myc RNA
target sequence 114cugagcgauu cagaugauga a 2111521RNAArtificial
SequenceN-Myc RNA target sequence 115gccaguauua gacuggaagu u
2111621RNAArtificial SequenceN-Myc RNA target sequence
116cggacgaaga ugacuucuac u 2111721RNAArtificial SequenceN-Myc RNA
target sequence 117caccuccaug acagcgcuaa a 2111821RNAArtificial
SequenceN-Myc RNA target sequence 118cuucuacccg gacgaagaug a
2111921RNAArtificial SequenceN-Myc RNA target sequence
119agacagcagc aguugcuaaa g 2112021RNAArtificial SequenceN-Myc RNA
target sequence 120cauaccuaag uacuguaaua a 2112121RNAArtificial
SequenceN-Myc RNA target sequence 121ucggacuugc uagacgcuuc u
2112221RNAArtificial SequenceN-Myc RNA target sequence
122acguccgcuc aagaguguca u 2112321RNAArtificial SequenceN-Myc RNA
target sequence 123cacggagaug cugcuugaga a 2112421RNAArtificial
SequenceN-Myc RNA target sequence 124acgugccgga guugguaaag a
2112521RNAArtificial SequenceE2f1 RNA target sequence 125uaacugcacu
uucggcccuu u 2112621RNAArtificial SequenceE2f1 RNA target sequence
126cauccagcuc
auugccaaga a 2112721RNAArtificial SequenceE2f1 RNA target sequence
127uaagagcaaa caaggcccga u 2112821RNAArtificial SequenceE2f1 RNA
target sequence 128accucuucga cugugacuuu g 2112920RNAArtificial
SequenceE2f1 RNA target sequence 129acaucaccaa cguccuugag
2013021RNAArtificial SequenceE2f1 RNA target sequence 130cuacucagcc
uggagcaaga a 2113121RNAArtificial SequenceE2f1 RNA target sequence
131caggauggau augagauggg a 2113221RNAArtificial SequenceE2f1 RNA
target sequence 132cgcuaugaga ccucacugaa u 2113321RNAArtificial
SequenceE2f1 RNA target sequence 133cguggacucu ucggagaacu u
2113421RNAArtificial SequenceE2f1 RNA target sequence 134accugaugaa
uaucuguacu a 2113521RNAArtificial SequenceE2f1 RNA target sequence
135ccugaggagu ucaucagccu u 2113621RNAArtificial SequenceE2f1 RNA
target sequence 136cgcuaugaga ccucacugaa u 2113721RNAArtificial
SequenceE2f1 RNA target sequence 137accugaugaa uaucuguacu a
2113821RNAArtificial SequenceE2f1 RNA target sequence 138caggauggau
augagauggg a 2113921RNAArtificial SequenceE2f1 RNA target sequence
139cguggacucu ucggagaacu u 2114021RNAArtificial SequenceE2f1 RNA
target sequence 140accucuucga cugugacuuu g 2114121RNAArtificial
SequenceE2f2 RNA target sequence 141ccacucuaua agcagggcua a
2114221RNAArtificial SequenceE2f2 RNA target sequence 142gccuauguga
cuuaccagga u 2114321RNAArtificial SequenceE2f2 RNA target sequence
143gcagacagug auugccguca a 2114421RNAArtificial SequenceE2f2 RNA
target sequence 144ccgagggcca aguugugcga u 2114521RNAArtificial
SequenceE2f2 RNA target sequence 145cagcgaucuc uucgacuccu a
2114621RNAArtificial SequenceE2f2 RNA target sequence 146uccgugcugu
uggcaacuuu a 2114721RNAArtificial SequenceE2f2 RNA target sequence
147gaggacaacc ugcagauaua u 2114821RNAArtificial SequenceE2f2 RNA
target sequence 148guacggguga ggaguggaua a 2114921RNAArtificial
SequenceE2f3 RNA target sequence 149cccgcuuuac ucuucaggaa u
2115021RNAArtificial SequenceE2f3 RNA target sequence 150ccucauuaag
aagaagucua a 2115121RNAArtificial SequenceE2f3 RNA target sequence
151ccaaacuguu auaguuguga a 2115221RNAArtificial SequenceE2f3 RNA
target sequence 152ccugacucaa uagagagccu a 2115321RNAArtificial
SequenceE2f3 RNA target sequence 153ccaacucagg acauagcgau u
2115421RNAArtificial SequenceE2f3 RNA target sequence 154acgcgguaug
auacgucucu u 2115521RNAArtificial SequenceE2f3 RNA target sequence
155agauccucac cacgaacacu u 2115621RNAArtificial SequenceE2f3 RNA
target sequence 156gacuucaugu guaguugauu a 2115721RNAArtificial
SequenceE2f3 RNA target sequence 157acgaagucca gauaguccaa a
2115821RNAArtificial SequenceE2f3 RNA target sequence 158ccaaccuaga
aggaccguuu g 2115921RNAArtificial SequenceE2f3 RNA target sequence
159gucuuugagg ucugcuaaua u 2116021RNAArtificial SequenceH-Ras RNA
target sequence 160caagagugcg cugaccaucc a 2116121RNAArtificial
SequenceH-Ras RNA target sequence 161agaggauucc uaccggaagc a
2116221RNAArtificial SequenceH-Ras RNA target sequence
162gaggauuccu accggaagca c 2116321RNAArtificial SequenceH-Ras RNA
target sequence 163aagagugcgc ugaccaucca c 2116421RNAArtificial
SequenceH-Ras RNA target sequence 164gacgugccug uuggacaucc u
2116521RNAArtificial SequenceH-Ras RNA target sequence
165uggcugcacg cacuguggaa u 2116620RNAArtificial SequenceH-Ras RNA
target sequence 166ccuguuggac auccuggaua 2016721RNAArtificial
SequenceH-Ras RNA target sequence 167ccaggaggag uacagcgcca u
2116821RNAArtificial SequenceH-Ras RNA target sequence
168gccuguugga cauccuggau a 2116921RNAArtificial SequenceH-Ras RNA
target sequence 169caagagugcg cugaccaucc a 2117021RNAArtificial
SequenceH-Ras RNA target sequence 170agaggauucc uaccggaagc a
2117121RNAArtificial SequenceH-Ras RNA target sequence
171cggaagcagg uggucauuga u 2117221RNAArtificial SequenceK-ras RNA
target sequence 172caguugagac cuucuaauug g 2117321RNAArtificial
SequenceK-ras RNA target sequence 173ccucguuucu acacagagaa a
2117421RNAArtificial SequenceK-ras RNA target sequence
174gaugccuucu auacauuagu u 2117521RNAArtificial SequenceK-ras RNA
target sequence 175aggacucuga agauguaccu a 2117621RNAArtificial
SequenceK-ras RNA target sequence 176uaguuggagc ugguggcgua g
2117721RNAArtificial SequenceK-ras RNA target sequence
177ccuacaggaa gcaaguagua a 2117821RNAArtificial SequenceN-Ras RNA
target sequence 178gaaaccuguu uguuggacau a 2117921RNAArtificial
SequenceN-Ras RNA target sequence 179cagugccaug agagaccaau a
2118021RNAArtificial SequenceN-Ras RNA target sequence
180caagaguuac gggauuccau u 2118121RNAArtificial SequenceN-Ras RNA
target sequence 181cagugccaug agagaccaau a 2118221RNAArtificial
SequenceN-Ras RNA target sequence 182gaaaccuguu uguuggacau a
2118321RNAArtificial SequenceN-Ras RNA target sequence
183cgcacugaca auccagcuaa u 2118421RNAArtificial SequenceN-Ras RNA
target sequence 184ccaucaauaa uagcaaguca u 2118558DNAArtificial
Sequencec-Myc commercial DNA sequence encoding shRNA against cMyc
(Sigma) 185ccggcagttg aaacacaaac ttgaactcga gttcaagttt gtgtttcaac
tgtttttg 5818658DNAArtificial Sequencec-Myc commercial DNA sequence
encoding shRNA against cMyc (Sigma) 186ccggcctgag acagatcagc
aacaactcga gttgttgctg atctgtctca ggtttttg 5818758DNAArtificial
Sequencec-Myc commercial DNA sequence encoding shRNA against cMyc
(Sigma) 187ccggcctgag acagatcagc aacaactcga gttgttgctg atctgtctca
ggtttttg 5818858DNAArtificial Sequencec-Myc commercial DNA sequence
encoding shRNA against cMyc (Sigma) 188ccggccataa tgtaaactgc
ctcaactcga gttgaggcag tttacattat ggtttttg 5818958DNAArtificial
Sequencec-Myc commercial DNA sequence encoding shRNA against cMyc
(Sigma) 189ccggcaggaa ctatgacctc gactactcga gtagtcgagg tcatagttcc
tgtttttg 5819058DNAArtificial Sequencec-Myc commercial DNA sequence
encoding shRNA against cMyc (Sigma) 190ccgggcttca ccaacaggaa
ctatgctcga gcatagttcc tgttggtgaa gctttttg 5819158DNAArtificial
Sequencec-Myc commercial DNA sequence encoding shRNA against cMyc
(Sigma) 191ccggactgaa agatttagcc ataatctcga gattatggct aaatctttca
gttttttg 5819258DNAArtificial Sequencec-Myc commercial DNA sequence
encoding shRNA against cMyc (Sigma) 192ccggccagag gaggaacgag
ctaaactcga gtttagctcg ttcctcctct ggtttttg 5819358DNAArtificial
Sequencec-Myc commercial DNA sequence encoding shRNA against cMyc
(Sigma) 193ccggtacgga actcttgtgc gtaagctcga gcttacgcac aagagttccg
tatttttg 5819458DNAArtificial Sequencec-Myc commercial DNA sequence
encoding shRNA against cMyc (Sigma) 194ccggcctgag acagatcagc
aacaactcga gttgttgctg atctgtctca ggtttttg 5819558DNAArtificial
Sequencec-Myc commercial DNA sequence encoding shRNA against cMyc
(Sigma) 195ccggatcatc atccaggact gtatgctcga gcatacagtc ctggatgatg
attttttg 5819658DNAArtificial Sequencec-Myc commercial DNA sequence
encoding shRNA against cMyc (Sigma) 196ccggactcgg tgcagccgta
tttctctcga gagaaatacg gctgcaccga gttttttg 5819757DNAArtificial
SequenceL-Myc commercial DNA sequence encoding shRNA against L-Myc
(Sigma) 197ccggcctgtg ccactaaact acattctcga gaatgtagtt tagtggcaca
ggttttt 5719857DNAArtificial SequenceL-Myc commercial DNA sequence
encoding shRNA against L-Myc (Sigma) 198ccggcgagga catctggaag
aaattctcga gaatttcttc cagatgtcct cgttttt 5719957DNAArtificial
SequenceL-Myc commercial DNA sequence encoding shRNA against L-Myc
(Sigma) 199ccggcattgg ctcttctcaa gctctctcga gagagcttga gaagagccaa
tgttttt 5720057DNAArtificial SequenceL-Myc commercial DNA sequence
encoding shRNA against L-Myc (Sigma) 200ccggcaggaa ctacgcctcc
atcatctcga gatgatggag gcgtagttcc tgttttt 5720157DNAArtificial
SequenceL-Myc commercial DNA sequence encoding shRNA against L-Myc
(Sigma) 201ccggcccaag cgactcgggt aaggactcga gtccttaccc gagtcgcttg
ggttttt 5720259DNAArtificial SequenceL-Myc commercial DNA sequence
encoding shRNA against L-Myc (Sigma) 202ccggtggcgc ttagagagga
caatactcga gtattgtcct ctctaagcgc cattttttg 5920359DNAArtificial
SequenceL-Myc commercial DNA sequence encoding shRNA against L-Myc
(Sigma) 203ccggtgttgg taaacagttt ggaaactcga gtttccaaac tgtttaccaa
cattttttg 5920459DNAArtificial SequenceL-Myc commercial DNA
sequence encoding shRNA against L-Myc (Sigma) 204ccggtctcca
gttggcttta ctttactcga gtaaagtaaa gccaactgga gattttttg
5920559DNAArtificial SequenceL-Myc commercial DNA sequence encoding
shRNA against L-Myc (Sigma) 205ccgggaggct tagagataga caatcctcga
ggattgtcta tctctaagcc tcttttttg 5920657DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
206ccggcagcag cagttgctaa agaaactcga gtttctttag caactgctgc tgttttt
5720757DNAArtificial SequenceN-Myc commercial DNA sequence encoding
shRNA against N-Myc (Sigma) 207ccgggcgtcg cagaaaccac aacatctcga
gatgttgtgg tttctgcgac gcttttt 5720857DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
208ccggctgagc gattcagatg atgaactcga gttcatcatc tgaatcgctc agttttt
5720957DNAArtificial SequenceN-Myc commercial DNA sequence encoding
shRNA against N-Myc (Sigma) 209ccgggccagt attagactgg aagttctcga
gaacttccag tctaatactg gcttttt 5721057DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
210ccggcggacg aagatgactt ctactctcga gagtagaagt catcttcgtc cgttttt
5721158DNAArtificial SequenceN-Myc commercial DNA sequence encoding
shRNA against N-Myc (Sigma) 211ccggcacctc catgacagcg ctaaactcga
gtttagcgct gtcatggagg tgtttttg 5821258DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
212ccggcttcta cccggacgaa gatgactcga gtcatcttcg tccgggtaga agtttttg
5821358DNAArtificial SequenceN-Myc commercial DNA sequence encoding
shRNA against N-Myc (Sigma) 213ccggagacag cagcagttgc taaagctcga
gctttagcaa ctgctgctgt cttttttg 5821458DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
214ccggcatacc taagtactgt aataactcga gttattacag tacttaggta tgtttttg
5821559DNAArtificial SequenceN-Myc commercial DNA sequence encoding
shRNA against N-Myc (Sigma) 215ccggtcggac ttgctagacg cttctctcga
gagaagcgtc tagcaagtcc gattttttg 5921659DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
216ccggacgtcc gctcaagagt gtcatctcga gatgacactc ttgagcggac gtttttttg
5921759DNAArtificial SequenceN-Myc commercial DNA sequence encoding
shRNA against N-Myc (Sigma) 217ccggcacgga gatgctgctt gagaactcga
gttctcaagc agcatctccg tgttttttg 5921859DNAArtificial SequenceN-Myc
commercial DNA sequence encoding shRNA against N-Myc (Sigma)
218ccggacgtgc cggagttggt aaagactcga gtctttacca actccggcac gtttttttg
59
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