Phang T, Shi C, Wee A, Ngoi S, Li B, Lee H, Ong C
NATL UNIV SINGAPORE, DEPT COMMUNITY OCCUPAT & FAMILY MED, SINGAPORE 0511, SINGAPORE. NATL UNIV SINGAPORE, DEPT PATHOL, SINGAPORE 0511, SINGAPORE. NATL UNIV SINGAPORE, DEPT SURG, SINGAPORE 0511, SINGAPORE. NATL UNIV SINGAPORE, INST MOLEC & CELL BIOL, SINGAPORE 0511, SINGAPORE.
Int J Oncol. 1995 Jan;6(1):191-5.
54 sporadic colorectal cancers were analyzed for aberrations in the K-ras oncogene. DNA was extracted from frozen tissues obtained from surgical resection and analyzed for mutations in codons 12, 13 and 61 of the K-ras oncogene using single strand conformation polymorphism analysis (SSCP) and direct sequencing. Point mutations in the K-ras oncogene were found in 26/54 (48%) cases, all of which resulted in amino acid substitutions. No other types of mutations (e.g. insertions or deletions) were found. 4 of the mutations were at codon 12, 22 in codon 13 and only 1 was a codon 61 mutant. G-->A transitions were found to be predominant. A remarkable finding was the high preponderance of (13)Gly-(13)Ser mutations (54%). No correlation was observed between K-ras mutations and tumor location, Dukes' stage, differentiation levels, age or sex of the patient.
对54例散发性结直肠癌进行了K-ras癌基因畸变分析。从手术切除获得的冷冻组织中提取DNA，并使用单链构象多态性分析（SSCP）和直接测序分析K-ras癌基因第12、13和61密码子的突变。在26/54（48%）例病例中发现了K-ras癌基因的点突变，所有这些突变均导致氨基酸替换。未发现其他类型的突变（如插入或缺失）。其中4个突变位于第12密码子，22个位于第13密码子，只有1个是第61密码子突变体。发现G→A转换占主导地位。一个显著的发现是（13）甘氨酸-（13）丝氨酸突变的高度优势（54%）。未观察到K-ras突变与肿瘤位置、杜克分期、分化程度、患者年龄或性别之间的相关性。
