Clinicopathological and prognostic significance of p27 expression in oral squamous cell carcinoma: a meta-analysis.

Despite being already known that p27 can regulate cell proliferation, cell motility and apoptosis, the role of p27 expression in oral squamous cell carcinoma (OSCC) remains controversial. The purpose of this study was to comprehensively evaluate, with a meta-analysis, the clinicopathological and prognostic role of p27 expression in OSCC. A meta-analysis of eligible studies was performed to assess the effects of p27 expression on clinicopathological parameters and overall survival (OS) in patients with OSCC, using pooled relative risks with 95% confidence intervals. Heterogeneity and publication bias were also assessed. Fourteen studies involving a total of 1,010 patients met the inclusion criteria. Low p27 expression was significantly associated with advanced TNM stage (p<0.001), worse histology (p=0.025), and lymph node metastasis (p<0.001), but not with tumor size (p=0.181). The pooled RR of 0.743 (p=0.002) suggested that low p27 expression has a poor prognosis in patients with OSCC. A significant heterogeneity among studies was detected for lymph node status (χ(2)=34.60, I(2)=68.2%, p<0.001) and OS (χ(2)=14.86, I(2)=39.4%, p=0.095). We did not detect a significant publication bias in this meta-analysis. Our meta-analysis suggests that p27 expression status might be useful as a predictive biomarker in clinical practice, and might potently predict OS in OSCC patients.