Effects of different prostate cancer cells on the proliferation and differentiation of osteoblastic progenitor cells

Objective: To investigate the effects of conditioned medium (CM) of prostate cancer LNCaP and PC-3 cells on the proliferation and differentiation of pre-osteoblastic cell MC3T3-E1. Methods: MC3T3-E1 cells were incubated with 20% LNCaP CM, 20% PC-3 CM or a-MEM without CM (as a control), respectively. The proliferation of MC3T3-E1 cells was detected by cell counting kit-8 (CCK-8) method. The alkaline phosphatase (ALP) assay kit was used to evaluate the ALP activity in MC3T3-E1 cells. The alizarin red staining was used to detect the mineralization of MC3T3-E1 cells. The mRNA expression levels of collagen type ? alpha 1 (Col1a1), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2) mRNAs were measured by real-time fluorescence quantitative-PCR. Results: As compared with the control and LNCaP CM groups, PC-3 CM promoted the proliferation of MC3T3-E1 cells notably (P < 0.05). The ALP activity in MC3T3-E1 cells in the LNCaP CM group was higher than that in the control group (P < 0.05), and the area of mineralizaion nodes was wider (P < 0.05), but the result was opposite in the PC-3 CM group. The expression levels of Col1a1, OCN and RUNX2 mRNAs in MC3T3-E1 cells in LNCaP CM group were higher than those in the control group (P < 0.05), but PC-3 CM inhibited the expression levels of these mRNAs (P < 0.05). Conclusion: The PC-3 CM can stimulate the proliferation of osteoblastic progenitor cells and inhibit their differentiation. On the contrary, LNCaP CM can promote the differentiation of osteoblastic progenitor cells. These models can be used in vitro for further research on prostate cancer bone metastasis, as they can affect proliferation and differentiation of osteoblastic progenitor cells differently. Copyright © 2013 by TUMOR.