胰腺癌K—ras基因的研究

STUDY OF MUTATIONS IN K-ras GENE IN PANCREATIC CANCER

采用PCR技术,以福尔马林固定、石腊包埋切片中所含DNA为模板,成功地对19例胰腺导管癌中的18例进行了K-ras基因的扩增。应用特异核酸探针和Southern杂交,检测了扩增后K-ras基因并发现15例(83.3％)胰腺导管癌含有K-ras基因点突变。其中12密码由GGT转换为GAT5例(33.3％),12密码由GGT转换为GTT6例(40.0％),13密码由GGC,转换为GAC4例(26.6％)。未证实K-ras基因突变与癌分化程度、转移和浸润率以及患者予后的关系。结果提示K-ras基因突变在胰腺导管癌中极为常见,可能在胰腺癌发生中起重要作用;检测此基因突变可作为胰腺导管癌早期诊断和发生监测的生物学指标。

Using in vetro gene amplification by polymerase chain reaction (PCR) and mutation detection by the allele specific oligonucleotide (ASO) hybridization of Southern analysis, the K - ras gene in 19 human exocrine pancreatic cancers had been exmined. Successful amplification of the gene was reached in 18 of 19 tumors from trace DNA centained in formalin -fixed paraffin -embedded tissue. 15 of 18(88. 3%) cancers were revealed to harbor point mutation in K - ras gene. Base transition from GGT to GAT(50%) and transversion from GGT to GTT (28. 6%) in 12 codon and transition from GGC to GAC in 13 codon (21. 4% ) were observed. No correlation of mutation of K -ras with the incidence of metastasis and invasion of the cancer or with the wurvival time of the patients was observed. These results suggest that mutations in K -ras gene are frequently found in pancreatic cancer and play a role in the carcinogenesis of this disease and therefore. it may serve as a marker for early diagnosis and mornitering the development of this cancer.