Silencing of CXCR2, but not CXCR7, induces cells invasion. A-C. Silencing of CXCR2, but not CXCR7, induces cells invasion in TE-1, EC9706 and EC109 cells, respectively. SiRNA, small interfering RNAs; CXCR, chemotaxis cytokine receptor; NS, nonspecific. *P < 0.05 compared with control group and NS siRNA group.