Detection of K-ras Mutation in Colonic Effluent Samples From Patients Without Evidence of Colorectal Carcinoma

作者：Makiko Tohi, Feng Luo, Ze’ev A. Ronai · 发表于：JNCI Journal of the National Cancer Institute · 年份：1994 · DOI：10.1093/jnci/86.13.1007 · 被引用次数：102 · 研究领域：Colorectal Cancer Screening and Detection、Colorectal Cancer Treatments and Studies、Genetic factors in colorectal cancer

BACKGROUND: K-ras gene mutation appears in more than 50% of patients with colon tumors. Both its frequency and early appearance may qualify this mutation as a potential biomarker. To enable early detection of mutant K-ras alleles, we had previously developed a sensitive polymerase chain reaction (PCR)-based assay, i.e., enriched PCR, which enables detection of one mutant K-ras allele present within 10,000 normal alleles. Using the enriched PCR, we were able to detect mutant K-ras alleles in "normal-appearing" colonic mucosa in patients with colorectal cancer. PURPOSE: A study was initiated to determine whether mutant K-ras alleles could be identified in colonic effluent samples of patients who may be at risk to develop colorectal cancer. METHODS: Over 9 years, colonic effluent samples were collected prior to routine colonoscopy from 39 patients who were apparently free of colorectal cancer. These samples were collected from patients with a family history of colorectal cancer (n = 7), adenomatous polyps (n = 7), previously resected colorectal cancer (n = 5), inflammatory bowel disorders (n = 13), normal colonoscopic examination (n = 6), and familial adenomatous polyposis (n = 1). All of the samples were double coded and analyzed for K-ras gene mutation. RESULTS: Of the 39 patients, seven were found to harbor mutant K-ras codon 12 alleles. Mutations were found in patients with a family history of colorectal cancer (three of seven), adenomatous polyps (one of seven), previously ...