Increased MACC1 expression indicates a poor prognosis independent of MET expression in gastric adenocarcinoma.

Metastasis-associated in colon cancer-1 (MACC1), a newly identified oncogene, promotes tumor proliferation and invasion via the MET pathway. The purpose of this study is to determine the clinical significance of MACC1 and MET expression in the long-term survival and recurrence in a large cohort of gastric carcinoma patients following curative resection. We evaluated the prognostic value of MACC1 and MET expression using immunohistochemistry in 331 gastric adenocarcinoma patients. MACC1-positive patients had lower overall survival (OS) or event-free survival (EFS) rates than MACC1-negative patients (P=0.039 and P=0.044, respectively), while MET positivity itself was not associated with either OS or EFS. Multivariate analysis identified the expression level of MACC1 protein as an independent negative prognostic factor for OS or EFS (P=0.021 and P=0.016, respectively). This study suggests that MACC1 is an independent prognostic factor in gastric adenocarcinoma and that the prognostic impact of MACC1 may be associated with MACC1 partners other than MET.