CXCR4 and breast carcinoma: To further investigate the impact of silencing the CXCR4 gene on the malignant bionomics of breast cancer cells, MDA-MB-231 cells were transfected with selected sequences of CXCR4-shRNA, and the CCK-8 kit, cell adhesion assays and wound-healing assays were used to determine changes prior to and following shRNA interference.