IN VITRO SCREENING OF CHEMOPREVENTIVE AGENTS IN DMBA-IND

诱导DMBA诱导的乳腺病变的方法先前已详细描述（Telang等人，PNAS 76：5886，1979; Mehta和Moon，Cancer Res. 46：5832，1986）。获得的BALB/c雌性小鼠用于研究。 用1g 17 -雌二醇+1mg孕酮皮下预处理动物9天。 切下胸部乳腺并在每ml培养基中含有5g胰岛素、5g催乳素、1g醛固酮和1g氢化可的松的Waymouth ′ s MB 752培养基中孵育10天，在第3天将腺体暴露于DMBA（2g/ml）24小时。 然后将腺体在单独的5 μ g/ml胰岛素存在下培养14天。 其他实验条件包括37 ℃温度，50%O2，5%CO2和45%N2气氛。 每个测试中包括两个对照组，DMSO和DMBA对照。 在培养的前10天，培养基中包含5种不同浓度的化学预防剂，浓度范围为1 x 10- 9 M至1 x 10- 5 M。在24天实验结束时，将腺体固定在福尔马林中，用明矾胭脂红染色，并评价这些腺体中乳腺病变的发生率和多样性。本试验将评估25种化学预防剂。

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.