Altered miR-21, miRNA-148a Expression in Relation to KRAS Mutation Status as Indicator of Adenoma-Carcinoma Transitional Pattern in Colorectal Adenoma and Carcinoma Lesions.
The aim of this study was to investigate the correlation between the KRAS mutations and characteristics of non-advanced and advanced colorectal adenomas for predicting the risk of increased malignant potential of adenomas that may influence the decision to offer follow-up endoscopic surveillance.
Two hundred sixty-nine colorectal adenomas were examined for KRAS and BRAF mutation and immunohistochemical staining of β-catenin, O6-Methyl Guanine DNA Methyltransferase (MGMT), and p53.
An increase of COX-2-positive cells in adenoma was observed in 11 (37.9%) lesions, 10 (90.9%) of which had a K-ras gene mutation, suggesting a significant correlation between COX-2 expression and K-ras gene mutation in colorectal adenomas.
The low incidence of KRAS mutations in nonpolypoid colorectal adenomas reported previously suggested a different genetic basis for the transformation process in these lesions.
The aim of this study was to investigate the prognostic value of K-RAS-2 gene mutations found in initial colorectal adenomas for predicting the risk of metachronous adenomas.
It has been suggested that some mutations in codons 12 and 13 of the K-ras gene are associated with the progression of colorectal adenomas to carcinomas.
The present series of sporadic colorectal adenomas indicates that codon 12 G-C and G-T K-ras-2 transversion mutations and DNA aneuploidy are correlated.