Int J Med Sci 2019; 16(5):766-773. doi:10.7150/ijms.29995

Research Paper

Immunohistochemistry of YAP and dNp63 and survival analysis of patients bearing precancerous lesion and oral squamous cell carcinoma

Sawako Ono, Keisuke Nakano, Kiyofumi Takabatake, Hotaka Kawai, Hitoshi Nagatsuka

Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan

Abstract

Background: Yes-associated protein (YAP) is a candidate oncogene in various human cancers, and recently, it has been reported that YAP expression and its activity was enhanced by ΔNp63. However, the role of YAP and ΔNp63 expression in carcinogenesis and progression of oral squamous cell carcinoma (OSCC) has been unknown. Therefore, we investigated how YAP and ΔNp63 influence carcinogenesis and progression of OSCC.

Methods: We performed immunohistochemical analyses in whole tissue samples to investigate YAP and ΔNp63 expression in normal oral mucosa, epithelial hyperplasia, oral epithelial dysplasia (OED; low/high grade), carcinoma in situ (CIS), and OSCC. Furthermore, in OSCC, we analyzed clinical significance by using Kaplan-Meier survival analysis.

Results: In normal oral mucosa and epithelial hyperplasia, YAP expression was primarily confined to the basal and parabasal layers, but YAP expression was elevated in OED, CIS, and OSCC. In OED, YAP and ΔNp63 expression levels were markedly higher in high grade than in low grade. In OSCC groups, YAP and ΔNp63 expression patterns tended to differ according to histopathological differentiation of OSCC. Furthermore, the YAP high expression group, which showed YAP staining in >50% positive cells with strong cytoplasmic staining or >10% positive cells with nuclear reactivity, showed a tendency to have a poor survival rate.

Conclusion: YAP and ΔNp63 expression levels correlated with grade of oral OED. Additionally, YAP expression was associated with OSCC survival rate. Our results suggested that YAP and ΔNp63 expression might serve as predictive markers to distinguish OSCC development and progression.

Keywords: YAP, ΔNp63, oral epithelial dysplasia, carcinoma in situ, oral squamous cell carcinoma

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How to cite this article:
Ono S, Nakano K, Takabatake K, Kawai H, Nagatsuka H. Immunohistochemistry of YAP and dNp63 and survival analysis of patients bearing precancerous lesion and oral squamous cell carcinoma. Int J Med Sci 2019; 16(5):766-773. doi:10.7150/ijms.29995. Available from http://www.medsci.org/v16p0766.htm