Influence of inhibitory polypeptide for CXCR4 on the expression of CXCR4 in the different strains of breast carcinoma cells

Objective: To study the influence of inhibitory polypeptide for CXCR4(NT21MP) on the expression of CXCR4 of the breast cancer cell strains SKBR3 and MCF-7 with different expression of HER-2 receptor.Methods: The expressions of HER-2 and CXCR4 in breast cancer cells MCF-7 and SKBR3 were detected by immunohistochemistry and RT-PCR;the two cells were treated by 1 μg/ml and 10 μg/ml NT21MP for 48 h;the expressions of CXCR4 mRNA and protein were determined by RT-PCR and Western bloting,respectively.Results: The expression of CXCR4 was similar in both SKBR3 and MCF-7(P>0.05),but the expression of HER-2 was statistically different(P<0.01);NT21MP could downregulate the expression of CXCR4 in MCF-7 and SKBR3 cells dramatically,but the difference exists in the different cells(P<0.01).Conclusions: NT21MP can downregulate the expressions of CXCR4 in MCF-7 and SKBR3 with different degree.