Fujita M, Enomoto T, Inoue M, Tanizawa O, Ozaki M, Rice J M, Nomura T
Department of Obstetrics and Gynecology, Osaka University Faculty of Medicine.
Jpn J Cancer Res. 1994 Dec;85(12):1247-56. doi: 10.1111/j.1349-7006.1994.tb02937.x.
To clarify the role of the p53 tumor suppressor gene in the development of human ovarian epithelial tumors and to study the association of p53 alterations with K-ras activation, a series of 70 common epithelial ovarian tumors from Japanese patients was studied. These included 31 serous adenocarcinomas, 12 mucinous adenocarcinomas, 5 mucinous tumors of borderline malignancy, 13 endometrioid adenocarcinomas, and 9 clear cell carcinomas. Allelic loss, recognized at the polymorphic site in codon 72 of the p53 gene, was detected in 14 of 36 (39%) informative cases by restriction fragment length polymorphism analysis and by single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR)-amplified DNA fragments. Mutations in the highly conserved regions of the p53 gene were detected by SSCP analysis of PCR-amplified fragments. Mutations were found in 22 of 70 (31%) ovarian tumors, including 1 of 5 mucinous tumors of borderline malignancy. Mutations were subsequently characterized by direct sequencing. Single missense base substitutions were detected in 13 ovarian carcinomas and in one case of mucinous tumor of borderline malignancy. Short (1-8 bp) deletions and insertions were found in 8 cases. Mutations in the p53 gene occurred more frequently in serous adenocarcinomas (14/31, 45%) than in all nonserous types of malignant epithelial tumors combined (7/34, 21%; P = 0.032). Point mutations in K-ras were identified by dot blot hybridization analysis of PCR-amplified fragments with mutation-specific oligonucleotides and by direct sequencing. The overall frequency of K-ras mutations was 19/70 (27%). K-ras mutations were found in 12 of 17 (71%) mucinous tumors (8/12 mucinous carcinomas [67%] and 4/5 mucinous tumors of borderline malignancy [80%]), and occurred more frequently than in serous carcinomas (4/31, 13%; P = 0.00009) or in all nonmucinous types of ovarian epithelial tumors combined (7/53, 13%; P = 0.00002). These data suggest that different combinations of oncogenes and/or tumor suppressor genes may be involved in the genesis and development of histologically distinct categories of common epithelial tumors of the human ovary.
为阐明p53肿瘤抑制基因在人类卵巢上皮性肿瘤发生中的作用，并研究p53改变与K-ras激活之间的关联，我们对一系列来自日本患者的70例常见上皮性卵巢肿瘤进行了研究。这些肿瘤包括31例浆液性腺癌、12例黏液性腺癌、5例交界性黏液性肿瘤、13例子宫内膜样腺癌和9例透明细胞癌。通过对p53基因第72密码子多态性位点的等位基因缺失进行检测，在36例信息充分的病例中，有14例（39%）通过限制性片段长度多态性分析以及聚合酶链反应（PCR）扩增DNA片段的单链构象多态性（SSCP）分析检测到等位基因缺失。通过对PCR扩增片段进行SSCP分析，检测p53基因高度保守区域的突变。在70例卵巢肿瘤中有22例（31%）发现突变，其中包括5例交界性黏液性肿瘤中的1例。随后通过直接测序对突变进行了特征分析。在13例卵巢癌和1例交界性黏液性肿瘤中检测到单错义碱基替换。在8例中发现短（1 - 8 bp）缺失和插入。p53基因的突变在浆液性腺癌中（14/31，45%）比在所有非浆液性恶性上皮性肿瘤类型总和中（7/34，21%；P = 0.032）更频繁发生。通过用突变特异性寡核苷酸对PCR扩增片段进行点杂交分析以及直接测序，鉴定K-ras中的点突变。K-ras突变的总体频率为19/70（27%）。在17例黏液性肿瘤中有12例（71%）发现K-ras突变（8/12黏液性腺癌[67%]和4/5交界性黏液性肿瘤[80%]），其发生频率高于浆液性腺癌（4/31，13%；P = 0.00009）或所有非黏液性卵巢上皮性肿瘤类型总和（7/53，13%；P = 0.00002）。这些数据表明，不同组合的癌基因和/或肿瘤抑制基因可能参与了人类卵巢常见上皮性肿瘤不同组织学类型的发生和发展。
