Clinical significance of c-met oncogene alterations in human colorectal cancer.

Abnormalities of the c-met oncogene have been studied in cancers of many organs including thyroid, lung, pancreas, and stomach. However, little is known about the clinical significance of c-met oncogene abnormalities in colorectal cancer. We investigated the amplification and overexpression of the c-met gene in surgically resected samples from 43 patients with colorectal cancer using Southern blot analysis and reverse transcription-polymerase chain reaction (RT-PCR). Four of 33 (12%) samples of colorectal cancer showed amplification of the c-met gene. Twelve of 43 (30%) exhibited overexpression of the c-met gene. The patients with c-met overexpression showed greater tumor size, compared to those without c-met overexpression (p < 0.05). However, there were no differences in clinical stage, histological differentiation, tumor markers, or overall survival between two groups. The findings of the present study suggest that overexpression of c-met gene plays an important role in growth of colorectal cancer.