目的：研究乳腺导管原位癌与浸润性导管癌染色体3p区域微卫星杂合性缺失（loss of heterozygosity，LOH）的发生情况。 方法： 选取本院2005年9月至2009年2月手术切除石蜡包埋的乳腺癌组织切块43例，应用激光显微切割技术留取组织中乳腺浸润性导管癌（invasive ductal type carcinoma，IDC）、导管原位癌（ductal carcinoma in situ，DCIS）及正常乳腺组织区域，采用毛细管电泳测序技术进行了4个微卫星位点的LOH检测。 结果： 40例乳腺癌患者中，染色体3p区域D3S1038、D3S1295、D3S1581、D3S3118等4个位点的LOH率分别为25.0%（8/40）、37.5%（15/40）、17.5%（7/40）和5.0%（2/40）。IDC的LOH率比DCIS稍高(47.5% vs 37.5%)，但差异无统计学意义。 结论： 乳腺导管癌染色体3P微卫星LOH是肿瘤发生的早期事件，DCIS的总LOH 频率已经接近于IDC。在乳腺癌发展过程中，新的微卫星位点发生了LOH。

Objective : To explore the loss of heterozygosity (LOH) of microsatellite sites at chromosome 3p in ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) lesions. Methods: Forty-three paraffin blocks were obtained from patients with invasive ductal carcinoma who received surgery (Sep. 2005 to Feb. 2009, Changhai Hospital). The IDC, DCIS and normal tissues were microdissected from paraffin sections. The LOH of 4 microsatellite sites was examined with the application of capillary electrophoresis sequencing techniques. Results: In 40 breast cancer cases, the frequencies of LOH at D3S1038, D3S1295, D3S1581 and D3S3118 were 25% (8/40), 37.5% (15/40), 17.5% (7/40) and 5% (2/40), respectively. The frequency of LOH in IDC group was higher than that in DCIS group with no significant difference (47.5% vs 37.5%). Conclusion: LOH at chromosome 3P site is an early event in the development of breast ductal carcinoma. The frequency of LOH in DCIS is close to that in IDC. In the development of breast carcinoma, new MS sites have LOH.

国家自然科学基金资助项目(No.30870975)