IN VITRO SCREENING OF CHEMOPREVENTIVE AGENTS IN DMBA-IND

之前已经详细描述了DMBA诱导的乳腺损伤的诱导过程(Telang等人，PNAS 76：5886,1979；Mehta和Moon，癌症研究，46：5832,1986)。以获得的BALB/c雌性小鼠为研究对象。动物皮下注射1g 17-雌二醇+1 mg黄体酮，连续9天。取胸腺，在每毫升含5克胰岛素、5克催乳素、1克醛固酮和1克氢化可的松的MB752培养液中孵育10天，第3天用DMBA(2克/毫升)培养24小时。然后在单独含有5克/毫升胰岛素的情况下培养14天。其他实验条件为：37×C温度、50%O2、5%CO2、45%N_2气氛。每项测试包括两个对照组，一个DMSO组和一个DMBA对照组。在培养的前10天，化学预防药物以从1×10-9M到1×10-5M的5种不同浓度被包括在培养基中。24天实验结束后，福尔马林固定腺体，明矾胭脂红染色，观察乳腺病变的发生率和多发性。有25种化学预防药物需要通过这项检测进行评估。

The procedure for the induction of DMBA-induced mammary lesions has been described in detail previously (Telang et al., PNAS 76:5886, 1979; Mehta and Moon, Cancer Res. 46:5832, 1986). BALB/c female mice obtained are used in the study. The animals are pretreated subcutaneously with 1 g 17 -estradiol + 1 mg progesterone for 9 days. The thoracic mammary glands are excised and incubated in Waymouth's MB752 medium with 5 g insulin, 5 g prolactin, 1 g aldosterone and 1 g hydrocortisone per ml medium for 10 days with a 24 hour exposure of the glands to DMBA (2 g/ml) on day 3. The glands are then cultured for 14 days in the presence of 5 g/ml insulin alone. The other experimental conditions include 37xC temperature, 50% O2, 5% CO2, and 45% N2 atmosphere. Two control groups are included in each test, a DMSO and a DMBA Control. The chemopreventive agents are included in the medium for the first 10 days of culture at 5 different concentrations ranging from 1 x 10-9M to 1 x 10-5M. At the end of 24 day experiment, the glands are fixed in formalin, stained with alum carmine and evaluated for the incidence and multiplicity of the mammary lesions in these glands. There are 25 chemopreventive agents to be evaluated by this assay.