DETECTION OF K-RAS MUTATIONS IN DNAS ISOLATED FROM FECES OF PATIENTS WITH COLORECTAL TUMORS BY MUTANT-ALLELE-SPECIFIC AMPLIFICATION (MASA)

作者：HASEGAWA Y; TAKEDA S; ICHII S; KOIZUMI K; MARUYAMA M; FUJII A; OHTA H; NAKAJIMA T; OKUDA M; BABA S; NAKAMURA Y

来源：Oncogene, 1995, 10(7): 1441-1445.

• FECES
• COLORECTAL CANCER
• GENETIC DIAGNOSIS
• K-RAS
• MASA (MUTATED ALLELE SPECIFIC AMPLIFICATION

K-ras mutations are found in approximately half of all colorectal tumors examined, To explore the possibility of detecting mutated K-ras rapidly and efficiently in DNAs isolated from fecal material, we applied the mutant allele specific amplification (MASA)-PCR method to DNA from feces of patients with colorectal tumors, Among 55 colorectal adenocarcinomas or adenomas examined, 19 were found to carry K-ras mutations in codons 12 or 13, We were able to PCR-amplify DNAs isolated from feces of 15 of these 19 patients, but in only three of the fecal samples, we were able to detect the K-ras mutations corresponding to tumor DNA by MASA and ethidium-bromide staining of the gel, The carcinomas in these three cases were more than 40 mm x 40 mm in size and located in the sigmoid colon or rectum, However, we identified the K-ras mutations in fecal DNAs of additional seven patients by MASA when the gels were blotted and probed with a radio-labeled oligonncleotide; the tumors in those patients had arisen in the distal half of the colon and the smallest of these tumors was only 7 mm x 5 mm, No K-ras mutations were detectable in feces of the remaining five cases, whose tumors were relatively small and/or located in the proximal region, The results suggested that the MASA-PCR system has potential for development as a simple, rapid and noninvasive method for diagnosing the presence of colorectal tumors that carry mutant K-ras alleles, particularly tumors located in the distal colon.

• 出版日期1995-4-6