Aim: Though the exact mechanism of yes-associated protein (YAP) in tumorigenesis is not well understood, studies have shown that YAP plays an imperative role in cancer advancement via the Hippo signaling pathway. The purpose of the present study was to appraise the clinicopathological correlation of YAP expression in various grades and stages along with different parameters like tumor size and nodal metastasis in oral squamous cell carcinoma (OSCC).
Materials and methods: Twenty-seven surgically excised specimens from patients with OSCC were selected for the study. Grading of the OSCC specimens was done according to Broder's grading system and staging had been done using tumor-node-metastasis (TNM) system by American Joint Committee on Cancer (AJCC). Comparative analysis of YAP expression and various aforementioned parameters of OSCC was performed and statistically analyzed.
Results: Differences in the expression of YAP was observed among well differentiated and moderately differentiated OSCC, with increased YAP expression with successive grades but was statistically insignificant. On evaluating YAP expression among various stages of OSCC, we observed that stages I, II, and IV demonstrated a weak expression of YAP, while stage III showed a strong expression but the differences were insignificant. Insignificant differences were also noted in YAP expression between different tumor sizes, while significant differences were observed between different nodal statuses.
Conclusion: Our results suggest that YAP could be responsible for extensive proliferation and invasiveness of OSCC.
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