Bone marrow mesenchymal stem cells promote the progression of prostate cancer through the SDF-1/CXCR4 axis in vivo and vitro

Purpose The aim of this study was to investigate the involvement of the SDF-1/CXCR4 axis in the process of BMMSC homing in prostate cancer (PCa) in vivo and in vitro. Methods After verification of BMMSCs, we fixed the concentration gradient of SDF-1 for BMMSC cultivation to analyze CXCR4 expression by qRT-PCR and flow cytometric analysis. Furthermore, we developed a non-contact co-culture system and explored the participation of the SDF-1/CXCR4 axis in PCa using qRT-PCR, flow cytometry, and ELISA. In addition, A green fluorescent protein (GFP)-transplanted methylnitrosourea (MNU)-induced PCa mouse model was established to investigate the CXCR4 expression in vivo. Results The CXCR4 expression was up-regulated with the increase in SDF-1 concentrations, and elevated SDF-1 had a significant promoting effect on cell proliferation and migration in BMMSCs. Moreover, the CXCR4 expression of BMMSCs was significantly increased in the non-contact co-culture model with vascular endothelial cells (VECs), and analysis of this model also showed that the proliferation and migration of BMMSCs were promoted in the presence of VECs. The ELISA assay showed that the SDF-1 levels in the co-culture model at 48 h were significantly increased. Twenty of the GFP-transplanted mice were divided into a PCa group and a control group, and four GFP-transplanted mice were observed to have prostate tumorigenesis. It also showed that CXCR4 was obviously increased in the prostate tissue of PCa mice. Conclusion Our findings suggest that BMMSCs could home and promote the proliferation and migration of PCa through the SDF-1/CXCR4 axis in vivo and in vitro.