[Soluble expression and activity evaluation of SDF-1/54R, a specific antagonist of CXCR7].

Objective: To construct a soluble prokaryotic expression vector of the CXCR7-specific antagonist SDF-1/54R and evaluate its activity.

Methods: SDF-1/54r gene amplified by PCR was inserted into the soluble expression vector pET-41a+ engineered with GST fusion tag, and the recombinant vector was transformed into E. coli strain BL21 (DE3). After IPTG induction of E. coli, the expressed recombinant protein was purified with GST affinity chromatography purification system and confirmed by SDS-PAGE and Western blotting assay. The target protein SDF-1/54R was obtained after digestion of the purified product with enterokinase. Breast cancer MCF-7 cells with high expression of CXCR7 was treated with SDF-1/54R and the cell proliferation and metastasis was evaluated with MTT and chemotaxis assays.

Results: The target protein SDF-1/54R obtained showed an obvious inhibitory effect on the proliferation and metastasis of MCF-7 cells as confirmed by MTT and chemotaxis assays.

Conclusion: SDF-1/54R is a good antagonist of CXCR7 and shows a potential value as an effective anti-cancer agent.