The effects of K562 on apoptosis of bone marrow stromal cells and secretion of TGF-β1 in vivro

Objective To investigate the effects of K562 on bone marrow stromal cells (BMSCs) by observing the alterations of apopotosis and the negative regulation of TGF-β1 secretion in separated culture and contact culture.Methods On the 2,4,7 and 12 day after culture the levels of TGF-β1 were measured by ELISA.The expression of TGF-β1 mRNA in BMSCs was determined by hybridization in situ.The apoptosis of BMSCs was detected by TUNEL.Results The quantity of normal BMSCs was significantly lower than that of control on day 12.The apoptosis of BMSCs in contact culture was significantly higher than that of control after 4 days (P0.01).The level of TGF-β1 was significantly higher than that of control after 4 days (P0.01).The positive rates of TGF-β1mRNA in normal BMSCs were significantly higher than that of control after 4 days (P0.01).Conclusion K562 inhibits apoptosis of BMSCs and upregulates the expression of TGF-β1,which may be one of the main factor that normal hemopoiesis is inhibited and hematopoietic microenvironments is injured by leukemia cells.