Metastasis-associated protein 1 (MTA1) in gastric cancer tissues is positively associated with poorer prognosis

Background: The present study examined the clinical significance of metastasis-associated protein 1 (MTA1) in the progression and patient survival of gastric cancer. Methods: Paraffin-embedded resected tissues of gastric cancer mucosa (n = 436) and adjacent normal mucosa (n = 92) were assessed immunohistochemically for MTA1 protein, and scored according to the percentage of cells positively stained for MTA1 combined with stain intensity. Associations between MTA1 staining scores and clinicopathological factors, including survival time, were evaluated. Results: The staining scores for MTA1 were significantly higher in gastric cancer tissues than in matched normal tissues. MTA1 scores positively correlated with tumor size, depth of invasion, presence of lymph node metastasis, lymphatic involvement, venous invasion, distal metastasis, and advanced clinical staging. Patients with high MTA1 scores in gastric cancer tissues had a significantly lower five-year survival rate compared with patients with low MTA1 scores. The multivariate analysis indicated that MTA1 protein levels in resected gastric cancer tissues, as reflected by immunohistochemical staining, are an independent prognostic index of gastric carcinoma (P < 0.01). Conclusion: MTA1 immunopositivity was significantly associated with progression of gastric cancer, and may be helpful in gastric cancer prognosis.