Low expression of SOCS-1 and SOCS-3 is a poor prognostic indicator for gastric cancer patients.

BACKGROUND AND OBJECTIVES: Inflammation plays an important role in gastric cancer (GC) development and progression. Suppressor of cytokine signaling (SOCS)-1 and SOCS-3 negatively regulate proinflammatory cytokine signaling; however, their prognostic significance in GC remains unknown. We evaluated the clinicopathological correlation and prognostic significance of SOCS-1 and SOCS-3 in GC.
METHODS: SOCS-1 and SOCS-3 mRNA levels were analyzed in 80 paired gastric tumor and adjacent normal mucosal tissues using a microarray dataset from the Gene Expression Omnibus. Univariate and multivariate analyses were performed to investigate the prognostic impact of SOCS-1 and SOCS-3 immunohistochemical expression on overall survival (OS) and relapse-free survival (RFS) in 186 consecutive GC patients who underwent curative surgery.
RESULTS: SOCS-1 and SOCS-3 mRNA expression levels were lower in gastric tumor tissues than in matched normal mucosa. OS and RFS were significantly longer in the high SOCS-1 and SOCS-3 expression groups than in their corresponding low expression groups (p < 0.05). High simultaneous SOCS-1 and SOCS-3 expression were associated with longer OS compared with low simultaneous SOCS-1 and SOCS-3 expression (68.8 vs. 22.2 months; p < 0.001). SOCS-1 [hazards ratio (HR) 0.54, 95 % confidence interval (CI) 0.33-0.87, p = 0.011] and SOCS-3 (HR 0.46, 95 % CI 0.26-0.80, p = 0.006) were independent prognostic factors for OS. Only SOCS-1 (HR 0.20, 95 % CI 0.11-0.38, p = 0.006) was an independent prognostic factor for RFS.
CONCLUSION: Low SOCS-1 and SOCS-3 expression are poor prognostic indicators in GC. GC patients with low SOCS-1 and SOCS-3 expression need close follow-up.