Thompson H J, Meeker L D, Tagliaferro A R, Becci P J
Cancer Res. 1982 Mar;42(3):903-5.
The inhibitory activity of retinyl acetate against the induction of ovarian hormone-responsive and -nonresponsive mammary gland adenocarcinomas was studied in intact and castrated female Sprague-Dawley rats. Three experiments were conducted. Mammary cancer was induced by a single p.o. administration of 7,12-dimethylbenz(a)anthracene (DMBA) at 50 days of age. Animals in Experiments 1 and 2 each received 20 mg DMBA, whereas those in Experiment 3 received 15 mg. In all experiments, animals were fed a chow diet supplemented per kg with either a placebo or 328 mg retinyl acetate starting 7 days after carcinogen treatment. In Experiment 1, rats were castrated at either 7, 60, or 90 days postcarcinogen and were killed 120 days after DMBA was given. In Experiment 2, rats were castrated 30 days after DMBA and were killed 240 days after carcinogen treatment. In Experiment 3, rats were castrated when a detected tumor attained a measurable diameter, and the hormone responsiveness of their tumors was subsequently determined. The experiment was terminated 279 days after DMBA treatment. In both intact and castrated rats, mammary tumor occurrence was inhibited by treatment with retinyl acetate. However, there were no differences in the latency to appearance time of hormone-responsive and -nonresponsive cancers in intact animals receiving either placebo or retinyl acetate. The data indicate that retinyl acetate inhibits DMBA-induced mammary tumorigenesis in either the presence or the absence of the ovaries. It appears that retinyl acetate is effective in inhibiting both ovarian hormone-responsive and -nonresponsive mammary tumors.
在完整和去势的雌性斯普拉格-道利大鼠中，研究了醋酸视黄酯对卵巢激素反应性和非反应性乳腺腺癌诱导的抑制活性。进行了三项实验。在50日龄时通过单次口服给予7,12-二甲基苯并(a)蒽（DMBA）诱导乳腺癌。实验1和2中的动物各接受20mg DMBA，而实验3中的动物接受15mg。在所有实验中，从致癌物处理后7天开始，给动物喂食每千克补充有安慰剂或328mg醋酸视黄酯的普通饮食。在实验1中，大鼠在致癌物处理后7、60或90天去势，并在给予DMBA后120天处死。在实验2中，大鼠在DMBA后30天去势，并在致癌物处理后240天处死。在实验3中，当检测到的肿瘤达到可测量直径时，大鼠去势，随后确定其肿瘤的激素反应性。实验在DMBA处理后279天终止。在完整和去势大鼠中，醋酸视黄酯处理均抑制乳腺肿瘤的发生。然而，接受安慰剂或醋酸视黄酯的完整动物中，激素反应性和非反应性癌症出现时间的潜伏期没有差异。数据表明，无论卵巢是否存在，醋酸视黄酯均抑制DMBA诱导的乳腺肿瘤发生。似乎醋酸视黄酯对抑制卵巢激素反应性和非反应性乳腺肿瘤均有效。
