阻断大鼠骨髓间充质干细胞向脂肪细胞分化与肿瘤发生相关性研究

【目的】分析骨髓间充质干细胞在体外定向分化为脂肪细胞的适宜诱导条件.阻断正常干细胞的分化过程,探讨肿瘤发生机理.【方法】利用贴壁培养法获得大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs),通过地塞米松、胰岛素和吲哚美辛联合诱导大鼠BMSCs,使其分化为脂肪细胞.在细胞分化过程中利用3-甲基胆蒽(3-MC)阻断大鼠BMSCs的分化过程.【结果】大鼠BMSCs分化试验显示:诱导30d后经油红O染色,细胞内可见脂肪细胞特有的红色脂滴沉淀,并且随着诱导时间的延长,油红O阳性细胞比例增加,脂滴增大,表明大鼠BMSCs已成功分化为脂肪细胞.大鼠BMSCs分化阻断试验显示:诱导30d后经油红O染色细胞内红色脂滴沉淀明显下降,表明阻断后的细胞具有脂肪细胞的特性,但分化不完全;形态学鉴定表现出:细胞接触抑制消失,细胞核异常,微核畸变率高,核型异常,表明阻断后的干细胞发生恶性转变.【结论】通过地塞米松、胰岛素和吲哚美辛的联合作用,诱导BMSCs成功向脂肪细胞分化.在BMSCs向脂肪细胞分化的过程中加入阻断剂3-MC,阻断其分化过程,表明干细胞分化过程受到阻断,细胞停止在分化的中间阶段,有转化成肿瘤细胞的趋势.

Relationship among differentiation of rat bone marrow mesenchymal stem cells into adipocytes and tumorigenesis

[Objective] To investigate the suitable induction conditions of bone marrow mesenchymal stem cells (BMSCs) in vitro to differentiate into adipocytes,we explore the pathogenesis of tumor by blocking the normal differentiation process of stem cells.[Method] BMSCs from rats were isolated,cultured and purified by the whole bone marrow adherence method,then induced rat BMSCs differentiate to adipose cells through dexamethasone,insulin and indomethacin.In the process of cell differentiation,using 3-methylcholanthrene (3-MC) block the differentiation of BMSCs.[Result] After 30 days of induction oil red O staining,produced a strong reaction in cells,and with the induction time,the proportion of oil red O-positive cells increased lipid droplets increases,indicating BMSCs successfully differentiated into adipogenic cells.After 30 days of induction oil red O staining,the deposition of lipid droplets significantly reduced,indicating blocked cells with the characteristics of fat cells,but not fully differentiated.Morphological identification showed that cell contact inhibition disappeared,abnormal nucleus,micronucleus aberration and karyotype abnormalities,indicating blocked the stem cell malignant transformation.[Conclusion] BMSCs were induced to differentiate into adipocytes through the combined action of dexamethasone,insulin and indomethacin.In the process of differentiation of BMSCs into adipocytes,blocking agent 3-MC was added to block the differentiation process.The results show that stem cell differentiation process by blocking cell division stops in the intermediate stage,the cells show the unlimited proliferation phenomenon and malignant change happened.This experiment provided new evidence for cancer stem cell originated in suppression of stem cell differentiation.