Evaluation of YAP protein expression and its value in tumorigenesis in molecular subtypes of invasive ductal carcinoma: an immunohistochemical study

Background: Yes-associated protein (YAP) is a transcription factor with contradictory results in breast cancer research, as it can act either as an oncogene or as a tumor suppressor. We aimed to clarify the role of YAP in breast cancer by examining YAP protein expression in different molecular subtypes of invasive ductal carcinoma and evaluate its value in prognosis. Materials and methods: Immunohistochemical study for the expression of YAP and Ki-67 in 142 cases with invasive ductal carcinoma was conducted. The study included 50 luminal A, 32 luminal B, 27 HER-2 overexpressed, and 33 triple-negative cases. Fluorescent in-situ hybridization analysis for HER-2 in cases with 2+ protein expression was performed. The association with clinicopathological features was studied. Results: Nuclear YAP was expressed in 28.9% (41/142) and cytoplasmic YAP was expressed in 28.2% (40/142) of breast cancer cases. Nuclear YAP protein was expressed differently according to the molecular subtypes of breast cancer (P
Source: Egyptian Journal of Pathology - Category: Pathology Tags: Original Articles Source Type: research