Figure 2

Runx2 suppression increases caspase 3 cleavage in invasive MDA-MB-231 cells in response to glucose-deprivation. A, B, C) The Runx2-RNAi or control MDA-MB-231 cells were deprived of glucose and serum for three hours. The cells were then left untreated or treated with 10% serum for 10 minutes (A). The cells were then substituted with glutamine for 1 hour (B), and indicated concentrations of glucose for 24 hours (C). The whole cell lysates were examined for cleaved caspase-3, pAkt and total Akt expression, while Lamin A/C protein levels served as the loading control in Western blotting. D) The Runx2 knockdown or control MDA-MB-231 cells were utilized to re-express a constitutively active form of Akt (CA-Akt) or matching green fluorescent protein (GFP) vector control. The whole cell lysates were analyzed for Akt exogenous CA-Akt over-expression. E) The control or Runx2 knockdown MDA-MB-231 cells expressing CA-Akt or GFP were deprived of serum and glucose for 24 hours. The fixed cells were analyzed for sub-G1 population. F) The mean ± standard deviation of percent sub-G1 cells is shown. * indicates P-value <0.05 derived from unpaired Student’s t-test.