CXCR4 and breast cancer: Furthermore, Pinto et al. [24] demonstrated that BCL-6 could significantly increase expression of three metastasis-related genes -- CXC-chemokine receptor 4 (CXCR4) [31], fms-like tyrosine kinase-1 (FLT-1) [32], and integrin-b-3 [33] -- in breast cancer cell lines.