卵巢浆液性交界及恶性肿瘤K-ras基因突变分析

K-ras mutation analysis in ovarian serous borderline and malignant tumors

目的探讨K-ras基因在卵巢浆液性交界及恶性肿瘤发生发展过程中的作用。方法收集51例卵巢浆液性肿瘤标本,包括经典型交界性浆液性肿瘤18例,微乳头型交界性浆液性肿瘤11例,浸润性微乳头型浆液性癌12例,经典型浆液性癌10例。采用显微切割技术获取肿瘤细胞后,提取基因组DNA、PCR技术扩增K-ras基因第一外显子,通过直接测序的方法鉴定K-ras基因第12、13密码子的突变情况。结果1例经典型交界性浆液性肿瘤K-ras基因第12密码子发生突变,突变类型为GGT→GTT即甘氨酸→缬氨酸,余50例标本未见突变;所有标本K-ras基因第13密码子均为野生型。结论K-ras基因第12、13密码子在被检患者中卵巢浆液性交界及恶性肿瘤中的突变频率很低,其在该肿瘤发生发展过程中可能不起主要作用。

Objective To investigate the roles of K-ras gene in the tumorigenesis of ovarian serous borderline and malignant tumors. Methods Fifty one tissue samples of ovarian serous tumors, including 18 conventional serous borderline tumors, 11 micropapillary serous borderline tumors, 12 invasive micropapillary serous carcinomas, and 10 conventional serous carcinomas were investigated for the presence of K-ras mutation. DNA was extracted after microdissection of the tumor tissue, the exon 1 of K-ras gene was amplified by PCR, and the presence of mutation at the codons 12 and 13 was evaluated by direct sequencing analysis. Results GGT to GrIT mutation at codon 12 of the K-ras gene was found in one conventional serous borderline tumors,resulting in valine to glycine substitution. All other 50 cases showed no K-ras mutation. All tumors had a wild-type codon 13. Conclusions Mutations of K-ras at codons 12 and 13 in ovarian serous tumors are very rare in this series of patients, suggesting a difference present between the Chinese and Caucasian populations. K-ras mutations may play a less important role in the tumorigenesis of ovarian serous tumor of the Chinese patients.