CXCR4 and cancer: Besides, >60% reduction in cancer cell invasion was observed in CXCR4-silenced pLKO-miR-139-transduced MDA-231 cells as compared to the control shRNA-treated cells, suggesting that the restored tumor invasiveness because of anti-miR139 treatment in these cells was significantly decreased by knockdown of CXCR4 and phosphorylated Akt proteins (Figure 5B,C).