Schwenke K, Peterson H P, Wangenheim K H, Feinendegen L E
Institute of Medicine, Research Center Jülich GmbH, Germany.
Leuk Res. 1995 Dec;19(12):955-61. doi: 10.1016/0145-2126(95)00096-8.
Various agents have been shown to induce differentiation in neoplastic cells. The present study aimed at investigating comparable phenomena induced by high doses of gamma-irradiation in the presence of physiological factors. The erythroleukemic K562 cells were gamma-irradiated or treated with cytosine-arabinoside (Ara-C), and examined for cell size, protein content, acetylcholinesterase (AChE)-activity and hemoglobin synthesis in relation to mitotic activity. At doses above 10 Gy, differentiation was induced, as recognized by elevated AChE-activity, accompanied by an increase in cell size and protein content and cessation of cell proliferation. Moreover, irradiation, as well as Ara-C, induced hemoglobin synthesis when cultures were supplemented with hemin prior to treatment. It is suggested that the basic mechanisms of differentiation induction are similar for ionizing radiation and certain chemical agents and are related to continued growth of essential cytoplasmic constituents during inhibition of mitotic activity.
已证实多种因子可诱导肿瘤细胞分化。本研究旨在调查在生理因子存在的情况下，高剂量伽马辐射诱导的类似现象。对红白血病K562细胞进行伽马辐射或用阿糖胞苷（Ara-C）处理，并检测其细胞大小、蛋白质含量、乙酰胆碱酯酶（AChE）活性以及与有丝分裂活性相关的血红蛋白合成情况。当剂量高于10 Gy时，可诱导分化，表现为AChE活性升高，同时细胞大小和蛋白质含量增加，细胞增殖停止。此外，在处理前向培养物中添加氯化血红素时，辐射以及Ara-C均可诱导血红蛋白合成。提示电离辐射和某些化学试剂诱导分化的基本机制相似，且与有丝分裂活性受抑制期间必需细胞质成分的持续生长有关。
