Mar 30 2010
Regulus Therapeutics Inc. today announced the publication of new results
in the journal Nature Biotechnology by Regulus scientists and
collaborators. The new study demonstrated that systemic treatment of a
microRNA therapeutic targeting microRNA-10b in tumor-bearing mice
inhibits breast cancer metastasis. Cancer-related metastasis is a major
cause of mortality and current cancer treatments have limited utility
suppressing the metastatic spread of cancer cells. microRNA therapeutics
targeting miR-10b represent a promising approach for the discovery and
development of a novel anti-metastatic agent.
“Recent reports
provide evidence that microRNAs are involved in cancer initiation,
progression, and metastasis. Targeting miR-10b represents a promising
approach for the research and development of a new anti-metastatic
therapy for breast cancer.”
"We are very excited by our continued progress in developing microRNA
therapeutics for the treatment of cancer. microRNAs are evolutionarily
conserved regulators of gene networks and are often dysregulated in
cancer. Targeting biological pathways by inhibiting microRNAs holds
considerable promise as a novel therapeutic strategy for cancer and
other human diseases," said Peter S. Linsley, Ph.D., Chief Scientific
Officer of Regulus. "The promising data in this Nature Biotechnology
publication further validates Regulus' microRNA product platform built
on the integration of biology, chemistry, and bioinformatics. Working
closely with our collaborators, the data generated from these efforts
advance our understanding of microRNA biology in cancer. Further studies
in additional animal models will help us determine the breadth of the
therapeutic potential of anti-miRs targeting miR-10b."
The new paper (Ma et al. (2010) Nature Biotechnology,
advanced online publication, 28 March 2010 (doi:10.1038/nbt.1618))
describes the therapeutic targeting of microRNA-10b in an in vivo
mouse model of cancer metastasis. Increased levels of miR-10b have been
found to be associated with high-grade malignancy; miR-10b is also found
to be highly expressed in metastatic breast tumor samples from patients.
Indeed, the over-expression of miR-10b in non-metastatic breast cancer
cells confers invasive and metastatic characteristics. In this study,
miR-10b was targeted in vivo with an anti-miR-10b oligonucleotide
in a mouse tumor metastasis model. Cancer cells were implanted in the
mammary fat pad of mice, forming primary breast tumors that rapidly
metastasize to the lung with 100% incidence. Mice treated with PBS or a
control compound rapidly developed macroscopically visible pulmonary
metastases. In contrast, an 86% decrease in macroscopically visible
pulmonary metastases was achieved with the anti-miR-10b treatment. This
therapeutic efficacy occurred in the absence of inhibition of growth of
the primary tumor, demonstrating the specific effect of anti-miR-10b on
the metastatic process.
"Most cancer-related mortality is caused by metastasis, which is
inadequately addressed by current cancer treatments," said Hubert C.
Chen, M.D., Vice President of Translational Medicine. "Recent reports
provide evidence that microRNAs are involved in cancer initiation,
progression, and metastasis. Targeting miR-10b represents a promising
approach for the research and development of a new anti-metastatic
therapy for breast cancer."
Cancer metastasis is a complex, multi-step process by which primary
tumor cells invade adjacent tissue, enter the systemic circulation, and
proliferate into a secondary tumor elsewhere in the body. Metastatic
disease to the lung is common and frequently involves cancerous cells
arising from primary breast tumors. Previous studies have shown miR-10b
to be highly expressed in metastatic breast cancer cells and involved in
the regulation of cell migration and invasion (Ma et al. (2007) Nature
449, 682-689).
In the field of microRNA therapeutics, Regulus controls fundamental
patent rights related to miR-10b, including compositions of matter for
various anti-miR compounds targeting miR-10b, and uses of these
compounds as in vivo inhibitors of miR-10b activity.
Source Regulus Therapeutics Inc.