Studies on Mechanisms and Blockade of Carcinogenic Action of Female Sex Hormones

Tumours of mice are induced by administration of Inj. Hydroxyprogesteroni Caproatis Co. (EP) in a practical subthreshold dose of carcinogenesis or 2. 5-5 times the human contraceptive dose (simply referred to as 2. 5- to 5-fold dose) combined with whole-body 0. 5 Gy gamma-ray irradiation. Malignant transformation of Syrian golden hamster embryo (SHE) cells is also induced by 5-fold dose of EP combined with 0. 3 Gy gamma-ray irradiation in vitro, thereby indicating that synergistic carcinogenesis can be obtained by combined use of physical and chemical carcinogens.The mechanisms of synergistic carcinogenesis have been further explained by cytogenetics, damage extent of the target cell DNA and production of free radicals. The Chinese traditional medicine with antioxidat-ing effect (Sulekang Capsule, SC), food additive--butylated hydroxyanisole (BHA) and green tea can effectively inhibit the carcinogenic effect of EP or EP combined with gamma rays in mice. They all have marked ability to scavenge or remove     

雌性激素致癌作用的机制和对其阻断的研究

本文从实际致癌阈剂量下的小剂量复方己酸孕酮注射液(EP),折合成人的2.5倍和5倍剂量和γ线0.5Gy照射联合诱发了小鼠肿瘤;EP5倍量和γ线0.3Gy体外照射联合诱发了SHE细胞的恶性转化,进一步说明理化致癌因子联合应用可达到协同致癌作用。从细胞遗传学、靶细胞DNA损伤程度和自由基的产生进一步阐明两者协同致癌的机制。具有抗氧化作用的中药(苏乐康)、食品添加剂——BHA和绿茶等有效地抑制了致癌作用,同时观察到它们均具有较强的捕获或清除自由基、减轻DNA损伤的作用。