TMPRSS4 as an emerging potential poor prognostic factor for solid tumors: A systematic review and meta-analysis
PURPOSE The present study investigated the clinical significance of transmembrane protease, serine 4(TMPRSS4) and extracellular signal-regulated kinases 1 (Erk1) in the development, progression and metastasis of gastric cancer. METHODS Immunohistochemistry was employed to analyze TMPRSS4 and Erk1 expression in 436 gastric cancer cases and 92 non-cancerous human gastric tissues. RESULTS Protein levels of TMPRSS4 and Erk1 were up-regulated in gastric cancer lesions compared with adjacent noncancerous tissues. High expression of TMPRSS4 correlated with age, size, Lauren's classification, depth of invasion, lymph node and distant metastases, regional lymph node stage and TNM stage, and also with expression of Erk1. In stages I, II and III, the 5-year survival rate of patients with high TMPRSS4 expression was significantly lower than in patients with low expression. Further multivariate analysis suggests that up-regulation of TMPRSS4 and Erk1 were independent prognostic indicators for the disease, along with depth of invasion, lymph node and distant metastasis and TNM stage. CONCLUSIONS Expression of TMPRSS4 in gastric cancer is significantly associated with lymph node and distant metastasis, high Erk1 expression, and poor prognosis. TMPRSS4 and Erk1 proteins could be useful markers to predict tumor progression and prognosis of gastric cancer.