Welsch C W, Scieszka K M, Senn E R, DeHoog J V
Int J Cancer. 1983 Oct 15;32(4):479-84. doi: 10.1002/ijc.2910320415.
The administration of caffeine to the drinking water (250 mg/l and 500 mg/l) of female Sprague-Dawley rats after treatment with 7,12-dimethylbenzanthracene (DMBA) (5 mg i.g.) resulted in an increase in mammary carcinoma incidence. The confidence levels of statistical significance for the groups of rats receiving the 250-mg and 500-mg doses of caffeine were greater than 0.70 and greater than 0.99, respectively. This increase in mammary carcinoma incidence was observed when caffeine treatment was initiated commencing 3 days after DMBA treatment and continued for 21 weeks. This effect was also observed when caffeine treatment was initiated commencing 20 weeks after DMBA treatment and continued for 6 weeks in rats relatively refractory to carcinogen treatment (mammary tumor-free at onset of treatment) and in rats relatively sensitive to the carcinogen (mammary tumor bearing at onset of caffeine treatment). Caffeine treatment of rats prior to and during carcinogen treatment did not significantly affect mammary carcinoma incidence. Thus caffeine consumption has been shown to significantly enhance the promoting phase but is without effect on the initiating phase of this carcinogenic process.
在用7,12 - 二甲基苯并蒽（DMBA）（腹腔注射5毫克）处理雌性斯普拉格 - 道利大鼠后，给其饮用水中添加咖啡因（250毫克/升和500毫克/升），结果导致乳腺癌发病率增加。接受250毫克和500毫克剂量咖啡因的大鼠组的统计学显著性置信水平分别大于0.70和大于0.99。当在DMBA处理后3天开始进行咖啡因处理并持续21周时，观察到乳腺癌发病率的这种增加。当在DMBA处理后20周开始进行咖啡因处理并在对致癌物处理相对不敏感的大鼠（处理开始时无乳腺肿瘤）和对致癌物相对敏感的大鼠（咖啡因处理开始时患有乳腺肿瘤）中持续6周时，也观察到了这种效果。在致癌物处理之前和期间对大鼠进行咖啡因处理并未显著影响乳腺癌发病率。因此，已证明摄入咖啡因可显著增强致癌过程的促进阶段，但对起始阶段没有影响。
