白血病细胞TGF-β_1含量减少及外源性TGF-β_1基因对HL-60细胞的作用  

Deficiency of TGF-β_1 in leukemic cells and the effects of exogenous TGF-β_1 gene on HL-60 cells

作　　者：陈元仲[1] 吴勇[1] 陈萍[1] 黄慧芳[1] 

机构地区：[1]福建省血液病研究所福建医科大学附属协和医院,福建福州350001

出　　处：《中国病理生理杂志》2006年第1期172-176,共5页Chinese Journal of Pathophysiology

基　　金：国家教委优秀年轻教师基金资助项目(No.95-503);福建省教委科研基金资助项目(No.K95033);国家"百千万人才工程"专项基金资助项目

摘　　要：目的:研究白血病细胞是否存在转化生长因子β1(TGF-β1)量的异常以及这种异常在白血病发病机制中的可能作用。方法:应用ELISA法检测白血病细胞株和原代白血病细胞培养上清TGF-β1水平,进一步应用脂质体介导基因转移法将TGF-β1基因转染HL-60细胞,采用有限稀释法及G418筛选得到抗性细胞,应用RT-PCR、白血病细胞集落培养、裸鼠移植瘤成瘤试验、片段化DNA分析、流式细胞术检测HL-60细胞内TGF-β1、bcl-2、端粒酶反转录酶(hTERT)mRNA的表达变化等方法了解外源性TGF-β1基因对HL-60细胞体内外增殖、凋亡的影响。结果:白血病细胞株和原代白血病细胞培养上清TGF-β1水平明显低于正常对照组(P<0.01),转染TGF-β1基因后,HL-60细胞内TGF-β1mRNA表达上调,bcl-2、hTERTmRNA表达下调,细胞体外增殖受抑制,集落形成抑制率达78.3%,裸鼠移植瘤生长受抑制,荷瘤鼠生存期延长,细胞呈现凋亡特征性的梯形条带,凋亡比例达73.4%。结论:内源性TGF-β1水平降低是白血病的发病机制之一,外源性TGF-β1基因能够抑制HL-60细胞增殖,诱导细胞凋亡,该基因通过下调bcl-2、hTERTmRNA的表达而发挥作用。AIM： To explore the existence of deficiency of TGF- β1 in leukemia cells and its possible mechanism in the pathogenesis of leukemia. METJODS： The levels of TGF-β1 were detected by ELISA in the cultured supernatant of leukemia cell lines and primary cells from patients with acute leukemia. TGF - β1 gene was transduced into HL - 60 cells by lipofectin - mediated DNA transfection. In the presence of G418, the HL - 60 clone expressing TGF - β1 was selected. The effects of exogenous TGF-β1 gene on the proliferation and apoptosis of HL - 60 cells were studied by leukemic colony assay, tumorigenicity in athymic nude mice, DNA fragmentation and cell cycle analysis. The expression of intrinsic TGF-β1, bcl - 2 oncogene, hTERT mRNA on the apoptosis of HL - 60 cells induced by exogenous TGF - β1 gene were detected by RT - PCR. RESULTS： The levels of TGF - β1 were obviously lower in the supernatant of leukemia cell lines and primary cells from patients with acute leukemia, as compared with normal controls （ P 〈 0.01 ）. The expression of intrinsic TGF - β1 mRNA was up - regulated, while the expression of bcl - 2 and hTERT were down- regulated in HL-60 ceils after transfected with exogenous TGF-β1 gene. Clongenicity was reduced 78.3% in vitro and apoptosis cells were 73.4% and tumorigenicity was weakened in vivo in athymic nude mice. CONCLUSIONS： The lower TGF- β1 expression may contribute to leukemogenesis. Exogenous TGF - β1 gene inhibits HL - 60 cell proliferation and induces cells apoptosis via up - regulating the expression of intrinsic TGF-β1 and down - regulating the expression of bcl - 2 and hTERT.

关 键 词：基因 转化生长因子Β1 HL-60细胞 细胞凋亡 白血病 

分 类 号：R363[医药卫生—病理学]