The aim of the present study was to accurately evaluate the association of Sox2 expression with the survival of patients with digestive tract cancers. Relevant literatures were identified by comprehensively searching databases including the Pubmed, Embase, CBMdisc, and Wanfang (up to October 2014). A meta-analysis was performed to clarify the association between Sox2 expression and overall survival or clinicopathological parameters of patients with digestive tract cancers (esophageal, gastric, and colorectal cancers). The results showed a significant association between high Sox2 expression and poor overall survival in patients with digestive tract carcinomas (HR=1.55, 95% CI=1.04-2.31), especially for patients with esophageal cancer (HR=2.04, 95%CI=1.30-3.22), colorectal cancer (HR=1.40, 95% CI=1.04-1.89), and digestive tract adenocarcinoma (HR=1.80, 95% CI=1.12-2.89), for Europeans (HR=1.98, 95% CI=1.44-2.71) or patients who did not receive neoadjuvant treatment (HR=1.73, 95% CI=1.10-2.72). Furthermore, Sox2 over-expression was highly correlated with vascular invasion (OR=1.86, 95% CI=1.25-2.77) and poor differentiation (OR=1.88, 95% CI=1.14-3.08), especially in esophageal and colorectal cancers. In conclusion, Sox2 expression may serve as a novel prognostic factor for patients with digestive tract cancers. Over-expression of Sox2 that is correlated with vascular invasion and poor differentiation suggests poor outcomes of patients with digestive tract cancers.
Antineoplastic Agents ; therapeutic use ; Biomarkers, Tumor ; genetics ; metabolism ; Colorectal Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Esophageal Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Gastrointestinal Tract ; metabolism ; pathology ; Gene Expression ; Humans ; Neoadjuvant Therapy ; methods ; Neoplasm Grading ; Neoplasms, Vascular Tissue ; diagnosis ; drug therapy ; mortality ; secondary ; Prognosis ; SOXB1 Transcription Factors ; genetics ; metabolism ; Stomach Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Survival Analysis

PURPOSE: Heat shock proteins (HSPs) are highly conserved molecular chaperones. There are various studies that assess the prognostic value of HSPs in patients with esophageal cancer, but the conclusion remains controversial. This is the first meta-analysis study aiming to summarize the evidence on the suitability of HSPs to predict patients' survival. MATERIALS AND METHODS: Searching PubMed, Web of science and Medline until May 31, 2014, data were compared for overall survival in patients with down-regulated HSPs level with those with up-regulated level. We conducted a meta-analysis of 9 studies (801 patients) that correlated HSPs levels with overall survival. Data were synthesized with hazard ratios (HRs). RESULTS: The estimated risk of death was 2.93-fold greater in HSP27 negative patients than HSP27 positive patients [95% confidence interval (CI), 1.12-7.62]. When limited to esophageal squamous cell carcinoma (ESCC), the risk of death in HSP27 negative patients seemed more significant (HR, 3.90; 95% CI, 2.35-6.49). Decreased expression of HSP70 was also associated with worse survival in esophageal cancer (HR, 2.83; 95% CI, 1.90-4.23) and, when limited to ESCC, HR was 3.21 (95% CI, 1.94-5.30). Data collected, however, were not sufficient to determine the prognostic value of HSP90 in patients with ESCC nor esophageal adenocarcinomas (EADC). CONCLUSION: In this meta-analysis, reduced HSP27 and HSP70 expressions were associated with poor survival in patients with esophageal cancer, especially esophageal squamous cell carcinoma.
Adenocarcinoma/*diagnosis/*metabolism/mortality ; Carcinoma, Squamous Cell/diagnosis/*metabolism/therapy ; Esophageal Neoplasms/*diagnosis/*metabolism/mortality/therapy ; Gene Expression Regulation, Neoplastic ; HSP27 Heat-Shock Proteins ; HSP70 Heat-Shock Proteins ; HSP90 Heat-Shock Proteins ; Heat-Shock Proteins/*metabolism ; Humans ; Male ; Neoplasm Proteins ; Prognosis ; Survival ; Treatment Outcome