Subcellular Expression of Mammary Serine Proteinase Inhibitor (MASPIN) in Locally Advance Oral Squamous Cell Carcinoma

Objectives: Mammary serine protease inhibitor (MASPIN) has numerous interactions with tumor pathogenesis and progression. Its relationships with apoptosis and angiogenesis have proven the impact on prognosis. However, its exact role is not known and needs further work in relation to various human cancers. Current study was planned to investigate the subcellular expression of MASPIN in oral squamous cell carcinoma (OSCC) and to observe its relation with tumor grade. Methods: It was a descriptive study, conducted at the Department of Morbid Anatomy and Histopathology, University of Health Sciences, Lahore. Histological diagnosis of squamous cell carcinoma was confirmed in 50 cases, and expression of MASPIN was determined by avidinbiotin-peroxidase complex method of immunohistochemical staining. MASPIN expression was scored on the basis of intensity of staining and the percentage of the cells that stained positively. Data was analyzed with SPSS using appropriate statistical procedures. Results: Mean age of the patients was 56.84 ± 1.58 years with male to female ratio 1.3:1. All tumors were locally advancing (Stage III). Histologically, 58% tumors were Grade 1, other grades were less common. MASPIN expression was observed in 32 (64%) cases, and it was localized to the cytoplasm of the tumor cells in all cases. Among the positive cases, its expression was focal in 15 (44.1%), diffuse but moderate in 13 (38.2%) and diffuse and intense in 6(17.7%) cases. MASPIN expression was significantly associated (P: 0.043) and negatively correlated (P: 0.034) with tumor grade. Conclusions: MASPIN expression was observed in the majority of OSCC. However, it was localized to the cytoplasm of tumor cells in all cases. Loss of MASPIN expression was observed more frequently in poorly differentiated cancers.