REG I? is a biomarker for predicting response to chemotherapy with S-1 plus cisplatin in patients with unresectable stage IV gastric cancer.

ABSTRACT: BACKGROUND: The regenerating gene I? (REG I?) is involved in gastric carcinogenesis as an antiapoptotic factor. Therefore, we investigated whether REG I? confers resistance to chemotherapeutic drugs in gastric cancer (GC) cells and whether REG I? expression is useful for predicting the response to chemotherapy and outcome in patients with GC. METHODS: A total of 70 patients with unresectable stage IV GC received first-line chemotherapy with S-1 and cisplatin (S-1/CDDP). The expression of REG I? was evaluated immunohistochemically using biopsy samples obtained before chemotherapy, and its relationship to clinicopathological parameters was analysed statistically. The effects of REG I? gene induction on resistance to 5-FU or CDDP treatment were examined by cell survival assay and flow cytometry. RESULTS: Of the 70 patients with unresectable stage IV GC, 19 (27%) were positive for REG I? expression. The expression of REG I? was independently predictive of poorer progression-free and overall survival in such patients (hazard ratio (HR) 2.46; P=0.002 and HR 1.89; P=0.037, respectively). The gene induction of REG I? conferred resistance to cell death induced by 5-FU or CDDP in GC cells. CONCLUSION: In patients with stage IV GC, REG I?, which confers resistance to chemotherapeutic drugs in GC cells, is a potential biomarker for predicting resistance to S-1/CDDP treatment.

SUBMITTER: Sekikawa A 

PROVIDER: S-EPMC3566803 | biostudies-other | 2013 Feb

REPOSITORIES: biostudies-other