High TEAD4 Expression is Associated With Aggressive Clear Cell Renal Cell Carcinoma, Regardless of YAP1 Expression

Yes-associated protein 1 (YAP1) and transcriptional coactivator TEA domain transcription factor 4 (TEAD4) are the main effectors of the Hippo signaling pathway. Deregulation of the Hippo signaling pathway significantly impacts tumorigenesis and tumor progression. We evaluated the mRNA expression level of YAP1 and TEAD4 using the Gene Expression Profiling Interactive Analysis database and investigated the roles of YAP1 and TEAD4 in 349 surgically resected clear cell renal cell carcinoma (CCRCC) samples through immunohistochemical analysis. High YAP1 and TEAD4 expression were observed in 57 (16.3%) and 131 (37.5%) cases, respectively. High YAP1 expression was associated with a low nuclear grade only. High TEAD4 expression was significantly associated with large tumor size, high nuclear grade, lymphovascular invasion, advanced pT classification, advanced clinical stage, sarcomatous differentiation, and metastasis. CCRCC with YAP1-low/TEAD4-high expression was significantly associated with aggressive clinicopathological variables and poor outcomes. For CCRCC, higher tumor stage, sarcomatous differentiation, and metastasis were the independent prognostic factors for overall survival (OS) and disease-free survival (DFS). High TEAD4 expression was significantly associated with short OS and DFS but was not an independent prognostic factor. High TEAD4 and YAP1-low/TEAD4-high expression significantly correlated with adverse clinicopathological factors and worse OS and DFS in patients with CCRCC. YAP1 expression was not significantly associated with clinicopathological factors or patient survival. Therefore, TEAD4 plays a critical role in CCRCC tumor progression independent of YAP1 and may be a potential biomarker and therapeutic target for CCRCC.