Therapeutic Application of MicroRNAs in Cancer - RNA Interference from Biology to Therapeutics - page 306

extremely high in cancer cells, shRNA cannot be available in cancer cells. The study
of MCPIP1 indicates that the expression of MCPIP1 may be correlated with the
stage of various cancers. Similarly, if the delivered miRNA cannot enter the cells
without binding to RNA-binding protein, Ago2, and target mRNA immediately, it
might be degraded by the XRN-2 mammalian homolog. Taken together, the findings
indicate that the basic mechanisms of miRNA homeostasis in the cells, along with
the development of miRNA delivery methods, should be studied in greater depth.
Although there are many obstacles for the therapeutic use of miRNAs to control
disease status, the great potential, however, is motivation for taking this field
forward.
Acknowledgment This work was supported in part by a Grant-in-Aid for the Third Term
Comprehensive 10-Year Strategy for Cancer Control, a Grant-in-Aid for Scientific Research on
Priority Areas Cancer from the Ministry of Education, Culture, Sports, Science, and Technology,
and the Program for Promotion of Fundamental Studies in Health Sciences of the National Institute
of Biomedical Innovation (NiBio), and the Japan Society for the Promotion of Science (JSPS)
through the “Funding Program for World-Leading Innovative R&D on Science and Technology
(FIRST Program)” initiated by the Council for Science and Technology Policy (CSTP).
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