Metastasis-associated protein is a predictive biomarker for metastasis and recurrence in gastric cancer

The metastasis-associated (MTA) gene family is a critical component of the nucleosome remodeling and histone deacetylase complex, and plays an important role in metastatic processes. We systematically evaluated dysregulation of the MTA family to clarify their clinical significance in gastric cancer (GC). One hundred and forty-five patients who underwent surgery for GC were evaluated. We analyzed the expression levels of the MTA family (MTA1, 2 and 3) by qPCR in GC tissue, and the MTA1 protein expression in primary cancer and matched normal mucosa (NM) was measured using immunohistochemical analysis. The expression of all the MTA family members was significantly increased in a stage-dependent manner, and elevated expression of all of the MTA family members was correlated with metastatic factors and prognosis in GC patients. Multivariate analysis revealed that MTA1 overexpression was an independent risk factor for survival. Especially, elevated expression of MTA1 was significantly correlated with recurrence, and was an independent risk factor for lymph node metastasis. Immunohistochemical analysis demonstrated that MTA1 was predominantly expressed in the nuclei of primary GC cells but was not expressed in NM and in the cancer stroma. In conclusion, quantification of MTA expression may support the accurate diagnosis of disease staging and may help predict clinical outcomes.