Hetland G
Institute of Immunology and Rheumatology, The National Hospital, Oslo, Norway.
Anticancer Drugs. 1997 Jul;8(6):618-22. doi: 10.1097/00001813-199707000-00010.
We studied whether inducers of cell differentiation alone could have cytotoxic effect on the promonocytic U937 and Mono Mac 6 cells in vitro. The cells were incubated with standard differentiating doses of interferon (IFN)-gamma, dibutyryl cAMP (Bt2cAMP) or the phorbol ester phorbol-12-myristate-13-acetate (PMA), with or without lipopolysaccharide (LPS), and both protein synthesis and viability were examined. In both U937 and Mono Mac 6 cells the incorporation of [3H]leucine was significantly reduced after PMA plus LPS stimulation, but not after IFN-gamma stimulation, when compared with controls. For U937 cells there was also reduced incorporation after Bt2cAMP stimulation. Trypan blue exclusion experiments and the number of cells remaining in the cultures indicated that Bt2cAMP-, PMA- and/or LPS-stimulated, but not IFN-gamma-stimulated, cells were less viable than unstimulated U937 or Mono Mac 6 cells. The results suggest that Bt2cAMP, PMA and LPS, but not IFN-gamma, are cytotoxic towards promonocytic cancer cell lines in vitro.
我们研究了单独的细胞分化诱导剂是否能在体外对单核细胞白血病U937和Mono Mac 6细胞产生细胞毒性作用。将细胞与标准分化剂量的干扰素（IFN）-γ、二丁酰环磷腺苷（Bt2cAMP）或佛波酯佛波醇-12-肉豆蔻酸酯-13-乙酸酯（PMA）一起孵育，添加或不添加脂多糖（LPS），然后检测蛋白质合成和细胞活力。与对照组相比，在PMA加LPS刺激后，U937和Mono Mac 6细胞中[3H]亮氨酸的掺入均显著减少，但在IFN-γ刺激后未减少。对于U937细胞，Bt2cAMP刺激后掺入也减少。台盼蓝排斥实验和培养物中剩余细胞数量表明，Bt2cAMP、PMA和/或LPS刺激的细胞，而非IFN-γ刺激的细胞，其活力低于未刺激的U937或Mono Mac 6细胞。结果表明，Bt2cAMP、PMA和LPS在体外对单核细胞白血病癌细胞系具有细胞毒性，而IFN-γ则不具有。
