Figure 5.

Radio-resistance triggered by the activation of the CXCL12/CXCR4 pathway is mediated by survivin in colorectal cancers cells. (a and b) Expression of survivin was up-regulated by exogenous CXCL12, whereas the inhibition of CXCR4 repressed the expression of survivin in colorectal cancers cells. (c) Western blot was utilized to measure the efficiency of survivin siRNA. (d) The CXCL12-mediated increase in cell viability during radiotherapy was weakened by survivin siRNA. (e and f) CXCL12-inhibited activation of caspase-3 and capase-9 was mitigated by the knockdown of survivin. Data are expressed as the mean ± SEM (*p < 0.05)