miR-6883 downregulates HIF1α in colorectal and breast cancer cells

Colorectal cancer (CRC) and breast cancer (BC) are deadly diseases that rank as the second and fourth leading causes of cancer-related deaths, respectively. We have previously shown that miR-6883 targets CDK4/6 and that palbociclib-mediated CDK4/6 inhibition destabilizes HIF1. We hypothesize that miR-6883 downregulates HIF1 in CRC and BC cells. miR-6883 was transfected under normoxia or hypoxia and western blot analysis revealed that miR-6883 downregulates CDK4/6 and HIF1 in CRC and BC cells, pointing to miR-6883 as a promising therapeutic to target hypoxic cancers or HIF1-deregulated tumor cells. Future studies will further investigate miR-6883 as a cancer biomarker, effects on HIF-related proteins and therapeutic uses in vivo. O_FIG O_LINKSMALLFIG WIDTH=164 HEIGHT=200 SRC="FIGDIR/small/556385v1_fig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@e0acadorg.highwire.dtl.DTLVardef@68b428org.highwire.dtl.DTLVardef@bc4dforg.highwire.dtl.DTLVardef@aa13ad_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 1.C_FLOATNO miR-6883 downregulates CDK4/6 and HIF1 in colorectal and breast cancer cells A) Colorectal cancer cells were treated with doses of palbociclib ranging from 0-20 {micro}M. Cell viability was measured by imaging the bioluminescent signal after addition of CellTiter-Glo reagent. B) Percent viability of colorectal cancer cells treated with palbociclib was calculated and nonlinear regression analysis was completed using GraphPad Prism software. C-H) CRC cells were transfected with miR-6883 under normoxia or hypoxia (<0.5% O2) and protein levels of CDK4/6, HIF1, Glut1, and Ran were measured by Western blot. C_FIG