Correlation of CHAF1A with adjuvant chemotherapy outcome and microsatellite instability in gastric cancer.

Abstract

e15511 Background: Clinical outcomes of adjuvant chemotherapy in gastric cancer (GC) have considerable stage-independent variability, which underscores the need for predictive molecular markers. Previous studies indicated that CHAF1A played a critical role in tumor growth, but whether it was associated with adjuvant chemotherapy in GC was still unknown. This retrospective study investigated the prognostic value of CHAF1A in adjuvant chemotherapy of GC. Methods: A total of 325 stage IB-III patients with fluoropyrimidines (FU)-based adjuvant chemotherapy after curative D2 gastrectomy meeting eligibility criteria were selected. CHAF1A protein expression was determined by immunohistochemical method. The primary outcomes were Overall survival (OS) and Disease-free survival (DFS). Kaplan-Meier method was used to estimate survival curve and Cox model for multifactor analysis. Results: CHAF1A mRNA was overexpressed in GC tissues and positive CHAF1A protein expression was not associated with OS and DFS in overall patients treated by FU-based chemotherapy ( P = 0.391 and 0.511, respectively). However, as stratified by tumor sites, positive CHAF1A expression was associated with poor OS and DFS in non-cardia cancer ( P = 0.009 and 0.007, respectively) but not in cardia cancer ( P = 0.229 and 0.112, respectively). Multivariate analysis indicated that CHAF1A expression level was still an independent predictor for both OS (HR = 2.42; 95% CI: 1.12-5.20; P = 0.024) and DFS (HR = 1.91; 95% CI: 1.03-3.54; P = 0.039) in non-cardia GC. Furthermore, CHAF1A was correlated with the status of microsatellite instability ( P = 0.025). Conclusions: CHAF1A might be a predictor for outcomes of FU-based adjuvant chemotherapy in patients with non-cardia GC, but needed further prospective studies to confirm.