Prognostic significance of TAZ expression in various cancers: a meta-analysis

BACKGROUND: The overexpression of transcriptional coactivator with PDZ-binding motif (TAZ), a Hippo pathway effector, was detected in a variety of cancers. However, controversies remain in published studies on the prognostic value of TAZ expression in cancer. We performed a meta-analysis to demonstrate the prognostic significance of TAZ in overall survival (OS) and its association with clinicopathologic characteristics. METHODS: A systematic literature search was performed by using PubMed, EMBASE, and Web of Science databases for eligible studies investigating the association between TAZ and survival. After extracting data, we used hazard ratio (HR), odds ratio (OR) and 95% confidence intervals (95% CIs) for association evaluation, I(2) for heterogeneity across studies, and Egger’s test and Begg’s funnel plot for publication bias assessment. RESULTS: A total of 15 studies including 2,881 patients were analyzed. Pooled results showed that a high TAZ was significantly associated with poor OS (HR =1.82, 95% CI =1.58–2.11; I(2)=33%; P=0.11). Subgroup analysis indicated significant correlation between TAZ overexpression and OS in patients stratified by ethnicity, sample size, sample source, and staining location. Furthermore, TAZ overexpression was associated with worse OS in hepatocellular carcinoma (HR =2.26, 95% CI =1.43–3.57; P=0.49) and gastrointestinal cancers (HR =2.00, 95% CI =1.54–2.58; P=0.97), but not in non-small-cell lung cancer (HR =1.71, 95% CI =0.93–3.14; P=0.08). TAZ overexpression was also found to be significantly associated with some clinicopathologic characteristics, including TNM stage (OR =2.56, 95% CI =1.60–4.11; P=0.52), tumor differentiation (OR =3.08, 95% CI =1.25–7.63; P=0.01), and lymph node metastasis (OR =2.53, 95% CI =1.81–3.53; P=0.58). CONCLUSION: TAZ overexpression is not only a predictive factor of poor prognosis but also associated with advanced TNM stage, poor tumor differentiation, and lymph node metastasis.