IN VITRO SCREENING OF CHEMOPREVENTIVE AGENTS IN DMBA-IND

dmba诱导乳腺病变的过程在之前已经有详细的描述（Telang et al., PNAS 76:5886, 1979; Mehta and Moon, Cancer Res. 46:58 832, 1986）。本研究使用获得的BALB/c雌性小鼠。用1 g 17 -雌二醇+ 1 mg黄体酮皮下预处理9天。切除胸部乳腺，在Waymouth的MB752培养基中，每ml培养基中加入5 g胰岛素、5 g泌乳素、1 g醛固酮和1 g氢化可的松，孵育10天，第3天将乳腺暴露于DMBA （2 g/ml）中24小时。然后在5 g/ml胰岛素单独存在下培养腺体14天。其他实验条件包括37xC温度，50% O2, 5% CO2, 45% N2气氛。每个测试包括两个对照组，DMSO组和DMBA组。在培养的前10天，培养基中加入5种不同浓度的化学预防剂，浓度范围为1 × 10- 9m至1 × 10- 5m。24天实验结束后，将腺体固定在福尔马林中，用胭脂红明矾染色，并评估这些腺体中乳腺病变的发生率和多样性。有25种化学预防剂需要通过该试验进行评估。

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.