Prognostic role of podocalyxin-like protein expression in various cancers: A systematic review and meta-analysis

Several studies were conducted to explore the prognostic significance of podocalyxin-like protein (PODXL) expression in various cancers, with contradictory. This study aims to summarize the prognostic significance of PODXL expression in cancers. PubMed, the Cochrane Library and Embase were completely retrieved. The prospective or retrospective studies focusing on the prognostic role of PODXL expression in cancers were eligible. The endpoints were overall survival (OS), diseasespecific survival (DSS) and disease-free survival (DFS). 12 studies involving a total of 5,309 patients were identified. The results indicated that high PODXL expression was significantly associated with worse OS when compared to the low PODXL expression (HR= 1.76, 95% CI= 1.53-2.04, p< 0.00001; I-2=41%, p=0.08). And similar results were detected in the subgroup analysis of analysis model, ethnicity, sample size, tumor type and antibody type. And the results also showed that high PODXL expression was obviously related to shorter DSS (HR= 2.47, 95% CI= 1.53-3.99, p=0.0002; I-2=66%, p= 0.03) and DFS (HR= 2.12, 95% CI= 1.58-2.85, p< 0.00001; I-2= 19%, p= 0.29). In conclusion, it was revealed that high PODXL expression is an unfavorable predictor of OS, DSS and DFS in patients with cancers, and high PODXL expression is a promising prognostic biomarker for cancers, especially for patients in European.