Metastatic tumor antigen 1 is closely associated with frequent postoperative recurrence and poor survival in patients with hepatocellular carcinoma.

Metastatic tumor antigen 1 (MTA1) is known to play a role in angiogenic processes as a stabilizer of hypoxia-inducible factor 1-alpha (HIF1-alpha). In this study, we examined whether overexpression of MTA1 affects the recurrence of hepatocellular carcinoma (HCC) after surgical resection and the survival of the patients. A total of 506 HCC patients who underwent hepatic resection were included in the study. They were followed up for a median of 43 months (range, 1-96 months) after hepatectomy. MTA1 expression levels were determined by the proportion of immunopositive cells (none, all negative; +, <50%; ++, >50%). The relationships between MTA1 expression and the HCC histological features, the appearance of recurrent HCC after surgical resection, and the survival of the patients were examined. Eighty-eight cases (17%) of the HCCs were positive for MTA1, although the surrounding liver tissues were all negative for MTA1; 62 cases were + and 26 cases were ++. Increased MTA1 expression levels in HCC were correlated with larger tumors (P = 0.04), perinodal extension (P = 0.03), and microvascular invasion (P = 0.008). Histological differentiation had marginal significance (P = 0.056). However, there was no association between MTA1 expression and age, sex, Child-Pugh class, and capsule invasion of HCC. Interestingly, MTA1 expression levels were significantly greater in hepatitis B virus (HBV)-associated HCC compared with hepatitis C virus (HCV)-associated HCC (P = 0.017). The cumulative recurrence rates of MTA1-positive HCCs were markedly greater than those of MTA1-negative HCCs (P < 0.0001). The cumulative survival rates of patients with MTA1-positive HCCs were significantly shorter than those of patients with MTA1-negative HCCs (P < 0.0001). In conclusion, our data indicate that MTA1 is closely associated with microvascular invasion, frequent postoperative recurrence, and poor survival of HCC patients, especially in those with HBV-associated HCC.