Prognostic Significance of TAZ Expression in Resected Non-Small Cell Lung Cancer

Abstract

Transcriptional coactivator with PDZ-binding motif (TAZ) is known to bind to a variety of transcription factors to control cell differentiation and organ development. Recently, TAZ has been identified as an oncogene and has an important role in tumorigenicity of non-small cell lung cancer (NSCLC). Therefore, TAZ may present a novel target for the future diagnosis, prognosis, and therapy for lung cancer. We investigated the relationship between TAZ expression and clinicopathological parameters and determined its prognostic significance concerning survival in patients with resected NSCLC. TAZ expression was immunohistochemically studied in 181 consecutive patients with NSCLC and 20 cases of normal lung tissue. The association between expression of TAZ and clinicopathological parameters was evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of TAZ expression on survival. TAZ expression was observed in 121 of the 181 (66.8%) NSCLC. TAZ had nuclear and cytoplasmic expression. Clinicopathologically, TAZ expression was significantly associated with lung adenocarcinoma (p = 0. 002), poorer differentiation (p = 0.001), p-tumor, node, metastasis stage (p = 0.001), lymph node metastasis (p = 0.032), intratumoral vascular invasion (p = 0.004), pleural invasion (p = 0.003), adjuvant chemotherapy (p = 0.044), and poorer prognosis (p = 0.002). Multivariable analysis confirmed that TAZ expression increased the hazard of death after adjusting for other clinicopathological factors (hazard ratio, 2.56; 95% confidence interval, 1.39-4.66; p = 0.01). Overall survival was significantly prolonged in TAZ negative group when compared with TAZ positive group (61.8 versus 47.1 months; p < 0.0001), as was disease-free survival (44.3 versus 25.1 months; p < 0.0001). Adjuvant chemotherapy prolonged overall survival among resected NSCLC patients with TAZ positive expression (p = 0.001). This study suggests that TAZ expression is a prognostic indicator of poorer survival probability for patients with resected NSCLC.