“Polygenic Adaptation”
Researchers at Northwestern have discovered a genetic "kill code" that might enable the destruction of cancer cells.
This novel new therapy "downstream" of chemo might destroy cancer cells without affecting the body's immune system.
While no animal trials have been conducted, this potential therapy could signal the demise of chemotherapy.
Abstract—Many small-interfering (si)RNAs are toxic to cancer cells through a 6mer seed sequence (positions 2–7 of the guide strand). Here we performed an siRNA screen with all 4096 6mer seeds revealing a preference for guanine in positions 1 and 2 and a high overall G or C content in the seed of the most toxic siRNAs for four tested human and mouse cell lines. Toxicity of these siRNAs stems from targeting survival genes with C-rich 3′UTRs. The master tumor suppressor miRNA miR-34a-5p is toxic through such a G-rich 6mer seed and is upregulated in cells subjected to genotoxic stress. An analysis of all mature miRNAs suggests that during evolution most miRNAs evolved to avoid guanine at the 5′ end of the 6mer seed sequence of the guide strand. In contrast, for certain tumor-suppressive miRNAs the guide strand contains a G-rich toxic 6mer seed, presumably to eliminate cancer cells.
“More than a decade of research on the mda-7/IL-24 gene has shown that it helps to suppress a majority of cancer types, and now scientists are focusing on how the gene drives this process by influencing microRNAs. Published this week in the journal Proceedings of the National Academy of Sciences, the findings could potentially have implications beyond cancer for a variety of cardiovascular and neurodegenerative diseases caused by the same microRNA-driven processes.”
