K-ras and p53 mutations in human colorectal aberrant crypt foci.
Aberrant crypt foci (ACF) are putative precursor lesions of colon cancer, recently identified on the methylene blue-stained mucosal surface of human colon. No mutations in K-ras or p53 genes were found by non-radioactive single-strand conformation polymorphism analysis in 14 ACF collected from five patients. Using the more sensitive method of allele-specific polymerase chain reaction (PCR) for K-ras, 8 of 14 ACF were found to contain K-ras mutations, suggesting that mutated cells are present in minute clones in ACF. No dysplasia was observed in any of the ACF containing a mutated clone. The presence of K-ras mutations in ACF suggests that these lesions occur at a very early stage in human colorectal carcinogenesis.
Losi
L
L
Istituti di Anatomia e Istologia Patologica, University of Modena, Italy.
Roncucci
L
L
di Gregorio
C
C
de Leon
M P
MP
Benhattar
J
J
D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D016158:Genes, p53; D011905:Genes, ras; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D011230:Precancerous Conditions / Q000235:genetics* / Q000473:pathology