CXCR4 and breast carcinoma: In the present study, treatment of the MDA-MB-231 breast cancer cell line, which express Nrp2, endogenous VEGF-C, and cytoplasmic or nuclear CXCR4 [8,14,16], with anti-Nrp2 antibody significantly inhibited cytoplasmic CXCR4 protein expression.