Interaction between osteoblast of bone marrow microenvironment with leukemia cells / 白血病·淋巴瘤

ABSTRACT

Objective To elucidate the interaction between osteoblast of bone marrow microenvironment and leukemia cells,and to investigate the role of osteoblast in the leukemia cells survival and apoptosis and the influence of leukemia cells on the osteoblast.Methods Leukemia cells from AML1-ETO9a-Rac1 mouse leukemia model and osteoblast cells were used.The ratio of GFP+ leukemia cells that co-cultured with or without osteoblast was detected by FACS.In addition,the apoptosis level of leukemia cells was detected by flow cytometry by PI and Annexin Ⅴ labeling.Activation level of PARP was determined by Western-blot.Real-time PCR (RT-PCR) was utilized to detect the mRNA level of TPO,N-cadherin,OPN and Ang1 in osteoblast which was separated from leukemic mice.Results The ratio of GFP+ cells in AE9a-Rac1 leukemia cells co-cultured with osteoblast cell was significantly higher than that of AE9a-Rac1 leukemia cells cultured alone.The apoptotic level of AE9a-Rac 1 leukemia cells cultured alone was significant higher than that of AE9a-Rac 1 leukemia cells in co-culture system.Western blot showed that activated level of PARP in AE9a-Rac1 leukemia cells co-cultured with osteoblast was lower than that cultured alone.RT-PCR result showed that TPO and N-cadherin mRNA levels in primary osteoblast separated from leukemic mice were higher than that from normal mice.Ang1 and OPN mRNA levels of osteoblast from leukemia mice were lower.Conclusion Osteoblast cell can support the survival and inhibit the apoptosis of leukemia cells.Leukemia cells can influence the functions of osteoblast by microenvironment associated cytokines production.