Lalle P, De Latour M, Rio P, Bignon Y J
Laboratoire d'Oncologie Moléculaire, Centre Jean Perrin, Clermont-Ferrand, France.
Oncogene. 1994 Feb;9(2):437-42.
A predisposing gene (BRCA-1) for breast and ovarian cancer has been located on chromosomal region 17q12-21. According to Knudson's hypothesis if this gene is a tumor suppressor gene, allelic losses would be found in tumors occurring in families with cancer aggregations. We studied 25 samples of both benign lesions and malignant tumors, from breast cancer site-specific families and other familial cancer aggregations. Allelic losses seem to be more frequent in tumors from breast site-specific families but also include the predisposing locus in other syndromes, suggesting a role of BRCA-1 in such families. Finding of allele losses near this locus in benign lesions suggests that such alterations may represent a first step in breast carcinogenesis. It is noteworthy that allele losses involve larger chromosome fragments in malignant tumors than in benign lesions where BRCA-1 is not lost, suggesting a similar mechanism for genomic deletion in the tumorigenesis of the colon and of the breast.
一种乳腺癌和卵巢癌的易感基因（BRCA - 1）已定位在染色体区域17q12 - 21。根据克努森假说，如果该基因是肿瘤抑制基因，那么在癌症聚集家族中发生的肿瘤中会发现等位基因缺失。我们研究了来自乳腺癌位点特异性家族和其他家族性癌症聚集群体的25份良性病变和恶性肿瘤样本。等位基因缺失在乳腺癌位点特异性家族的肿瘤中似乎更常见，但在其他综合征中也包括易感位点，这表明BRCA - 1在这些家族中发挥作用。在良性病变中该位点附近发现等位基因缺失表明这种改变可能是乳腺癌发生的第一步。值得注意的是，与未丢失BRCA - 1的良性病变相比，恶性肿瘤中的等位基因缺失涉及更大的染色体片段，这表明在结肠癌和乳腺癌的肿瘤发生过程中，基因组缺失存在类似机制。
