The role of MTA1 gene expression in human hepatocellular carcinoma.

The MTA1 gene has been identified as metastasis-associated gene and has been seen to correlate with the degree of invasion and lymphatic metastasis in gastric, colorectal, and esophageal carcinomas. We investigated the possible role of MTA1 gene expression in hepatocellular carcinoma (HCC). The mRNA expression level of the MTA1 gene was examined using reverse transcription polymerase chain reaction (RT-PCR) in HCC and paired non-tumor liver tissues which were obtained from 33 patients who underwent curative hepatectomy. The expression level of each case was calculated as tumor/non-tumor (T/N) ratios. To clarify the clinical significance of MTA1 gene expression in HCC, patient disease-free survival rate after hepatectomy were univariately analyzed using 25 clinicopathological variables, including MTA1 expression level. High expression (T/N > or =1) of the MTA1 gene in HCC as compared to the paired non-tumor tissues was recognized in 14 of 33 (42%) samples. With regard to the differentiation of HCC, the high expression of MTA1 gene in well or moderately differentiated HCC and poorly differentiated HCC were observed in 9 of 27 (33%) and 5 of 6 (83%) samples, respectively. There was no relation between expression levels of the MTA1 gene and cancer invasion to the portal vein or intrahepatic metastasis. However, the disease-free survival rate of the MTA1-high expression group (T/N > or =1) was significantly lower than that of the MTA1-low expression group (T/N <1) (p<0.05). High expression of the MTA1 gene is suggested to be a new prognostic indicator after curative hepatectomy for HCC.