PP072: The role of sparc in oral squamous cell carcinoma. A tissue microarray-based immunohistochemical study. Preliminary report

Abstract

Purpose Squamous cell carcinoma of the oral cavity (OSCC) remains a significant cause of morbidity and mortality, with approximately 540,000 new cases annually worldwide. SPARC is a matricellular glycoprotein that mediates interactions between cells and their microenvironment. During extensive matrix remodeling in neoplastic progression, SPARC is expressed in cancer-associated stroma and in malignant cells of some tumors. SPARC-induced changes in the tumor microenvironment can suppress or promote progression of different cancers depending on the tissue and cell type. Understanding the mechanism of matrix remodeling and its regulation by SPARC is essential for the development of new treatment strategies for highly aggressive cancers. Our aim was confirm the alteration of SPARC and investigate correlation with clinical–pathological data of HNSCC patients enclosed in our study. Materials and methods For a retrospective study we have built a prognostic TMA containing 119 OSCC to investigate SPARC protein expression by immunohistochemistry with a monoclonal-Ab and then we have confirmed our results on a prospective TMA of 30 cases. Results Preliminary data show SPARC over-expression in infiltrating layer of tumor and in the surrounding stromal microenvironment. Moreover SPARC tumor expression is correlated with deep localization and grading of tumor ( p -value p Conclusion In our tissue microarray immunohistochemical analyses, SPARC exhibited increased protein expression in tumor tissue compared with control tissue, and its expression was primarily localized within tumor-associated stroma. The association with a better overall survival need further study in order to confirm that over-expression of SPARC could be associated to the potential control of deep tumor invasion and an overall better outcome compared to SPARC down-regulated cancers.