[Cell kinetics of colorectal tumors with assessment by K-ras mutation and PCNA labeling index].
K-ras mutations in colorectal tumors (53 carcinomas, 21 adenomas) were investigated using oligonucleotide probes specific for mutations at codon 12, 13, or 61 of the K-ras gene by polymerase chain reaction and oligonucleotide hybridization techniques, and the proliferative activities were assessed immunohistochemically by using anti-proliferating cell nuclear antigen (PCNA), counting PCNA labeling index (LI). Point mutations were observed 18.8% in the adenomas, 40.0% in the intramucosal carcinomas and 27.0% in the invasive carcinomas. Fewer incidences of K-ras mutations in the invasive carcinoma suggested carcinomas without K-ras mutation invade rapidly. Clinicopathologically, K-ras mutation-positive carcinomas tended to show the presence of venous invasion (p < 0.005). There were many distant metastases in the K-ras mutation-positive cases (p = 0.07). Moreover, among adenocarcinomas a significant correlation was demonstrated between PCNA LI and the pattern of infiltrating growth (p < 0.05). Our data imply that the K-ras mutation gains access to invasion and metastasis, as well as the ras mutation occurs at the initiation of the carcinoma. The present data suggest that K-ras mutations in colorectal carcinomas are correlated with venous invasion, while cell proliferative activities are related to stromal invasion, and these factors are independent markers for invasion of colorectal carcinomas.
Tanaka
M
M
Department of Surgery (I), School of Medicine, Kanazawa University, Japan.
Omura
K
K
Ishida
F
F
Watanabe
Y
Y
D000236:Adenoma / Q000235:genetics / Q000473:pathology; D000368:Aged; D002277:Carcinoma / Q000235:genetics / Q000473:pathology; D002453:Cell Cycle; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology*; D005260:Female; D011905:Genes, ras; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009687:Nuclear Proteins / Q000032:analysis; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction; D018809:Proliferating Cell Nuclear Antigen
D009687:Nuclear Proteins; D015345:Oligonucleotide Probes; D018809:Proliferating Cell Nuclear Antigen