Wattenberg L W, Hochalter J B, Galbraith A R
Cancer Res. 1987 Aug 15;47(16):4351-4.
Studies have been initiated to find compounds that can trap direct-acting carcinogens within the stomach. Sodium thiosulfate (STS) is a potent nucleophile and in initial experiments was found to inhibit mutagenesis resulting from exposure of Salmonella typhimurium strain TA100 to the direct-acting carcinogens beta-propiolactone and styrene oxide. In in vitro experiments STS was shown to maintain its nucleophilicity in the acid pH range. It reacted with beta-propiolactone as rapidly at pH 2 as at pH 7.4. Thus STS has the prerequisite attributes to inhibit the carcinogenic effects of electrophiles in the stomach. Experiments were performed in which STS was administered by p.o. intubation to female A/J mice 5 min before p.o. administration of beta-propiolactone. Under these conditions, inhibition of formation of the forestomach tumors occurred. The data obtained suggest that use of nucleophiles to protect against direct-acting carcinogens is a potential strategy for chemoprevention.
已经开展了多项研究来寻找能够在胃内捕获直接作用致癌物的化合物。硫代硫酸钠（STS）是一种强效亲核试剂，在初步实验中发现它能够抑制鼠伤寒沙门氏菌TA100菌株暴露于直接作用致癌物β-丙内酯和环氧苯乙烷所导致的诱变作用。在体外实验中，STS在酸性pH范围内能保持其亲核性。它在pH 2时与β-丙内酯反应的速度与在pH 7.4时一样快。因此，STS具备抑制胃内亲电试剂致癌作用的必备特性。进行了相关实验，在经口给予β-丙内酯前5分钟，通过经口插管给雌性A/J小鼠施用STS。在这些条件下，前胃肿瘤的形成受到了抑制。所获得的数据表明，使用亲核试剂来预防直接作用致癌物是一种潜在的化学预防策略。
