Fig. 2.

The expression patterns of CXCL12 and CXCR4 in breast cancer cell lines. Total RNA and proteins were extracted from wild-type MCF-7, wild-type MDA-MB-435s, wild-type MDA-MB-231, MDA-MB-231–CXCL12 and MDA-MB-231–ZsGreen1. Then they were subjected to RT-PCR and western blot analysis, respectively, for CXCL12 and CXCR4. Both mRNA (a) and protein (b) expression of CXCR4 and very weak expression of CXCL12 were observed consistently in MDA-MB-231. CXCR4 and CXCL12 mRNA (a) and protein (b) expression was found in MDA-MB-435s. MCF-7 has very weak CXCR4 and CXCL12 mRNA and protein expression (a and b). So we picked MDA-MB-231 to be transfected with CXCL12. CXCL12 mRNA (a) and protein (b) expression was observed in MDA-MB-231–CXCL12 cells, but very weak in MDA-MB-231–ZsGreen1 or wild-type MDA-MB-231 cells. It is indicated that the stable CXCL12 transfection in MDA-MB-231 was successfully constructed