Open AccessHigher Frequency of Point Mutations in the c‐K‐ ras 2 Gene in Human Colorectal Adenomas with Severe Atypia than in Carcinomas
Author(s) -
Ando Masayuki,
Maruyama Michio,
Oto Michiei,
Takemura Katsuji,
Endo Mitsuo,
Yuasa Yasuhito
Publication year - 1991
Publication title -
japanese journal of cancer research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 0910-5050
DOI - 10.1111/j.1349-7006.1991.tb01836.x
Subject(s) - atypia , point mutation , adenoma , cancer research , pathology , mutation , carcinoma , colorectal cancer , medicine , biology , gene , oncology , cancer , genetics
Human colorectal carcinomas may be induced from adenomas or they may occur de novo. To examine which is the main pathway, we analyzed point mutations at codon 12 in the c‐K‐ ras 2 gene in 73 colorectal carcinomas, 13 metastatic tumors, 72 adenomas and 30 normal tissues. The c‐K‐ ras 2 codon 12 mutation frequency was 0/30 in normal tissues, 0/17 in adenomas with mild atypia, 3/37 (8.1%) in adenomas with moderate atypia, 15/18 (83.3%) in adenomas with severe atypia, 19/73 (26.0%) in primary carcinomas and 3/13 (23.1%) in metastatic tumors. The mutation frequency in adenomas with severe atypia was much higher than that in carcinomas. These results indicate that many colorectal carcinomas may not be induced through adenomas with severe atypia.