Expression of c-met proto-oncogene in primary colorectal cancer and liver metastases.
We have examined the expression of c-met mRNA in tissue from 27 colorectal cancers and ten liver metastases using the reverse transcriptase-polymerase chain reaction method. The expression of c-met mRNA in these tissues was quantified and the copy number of c-met mRNA to 10(8.0) copies of beta-actin mRNA was calculated. Mean copy numbers of c-met mRNA in cancer tissue and normal mucosa were 10(5.5) and 10(4.5) respectively. The c-met expression of cancer was significantly higher than that of normal mucosa (P < 0.0001). In 20 of 22 samples in which c-met expression of both tumor and corresponding normal tissue were examined, c-met was overexpressed in the cancer tissue. No correlation was found between c-met expression and the clinicopathologic background. The mean copy numbers of c-met mRNA in the tissue from the ten liver metastases and normal liver were 10(6.1) and 10(6.2) respectively. Although c-met expression in metastatic tissue was higher than that in the primary cancer tissue, the increase was not statistically significant. In three of four patients with synchronous liver metastases, c-met was overexpressed in the metastatic tissue compared with that in the corresponding primary cancer tissue. These results show that c-met is overexpressed in both primary colorectal cancer and liver metastases and suggest that c-met plays a role in the development of colorectal cancer liver metastases.
Fujita
S
S
Department of Surgery, National Cancer Center Hospital, Tokyo, Japan.
Sugano
K
K
D000199:Actins / Q000235:genetics; D003110:Colonic Neoplasms / Q000235:genetics* / Q000473:pathology; D004586:Electrophoresis; D017228:Hepatocyte Growth Factor / Q000502:physiology; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary*; D016133:Polymerase Chain Reaction; D000090063:Proto-Oncogene Mas; D019859:Proto-Oncogene Proteins c-met / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D012194:RNA-Directed DNA Polymerase; D012004:Rectal Neoplasms / Q000235:genetics* / Q000473:pathology
D000199:Actins; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D012333:RNA, Messenger; D017228:Hepatocyte Growth Factor; D019859:Proto-Oncogene Proteins c-met; D012194:RNA-Directed DNA Polymerase