Prognostic correlation of the phenomenon of epithelial-mesenchymal transition in localized tumor and lymph node and bone metastases of prostate cancer

• Grant number: 12/12620-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2012
• End date: January 31, 2014
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: José Pontes Junior
• Grantee: Maykon William Aparecido Pires Pereira
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Prostate cancer is the most common non cutaneous tumor and the second cause of death by cancer in western countries in males. Radical prostatectomy and radiotherapy are the main options of treatment with curative intention, but up to a quarter of patients have biochemical recurrence during the follow up. The classic prognostic factors can estimate tumor aggressiveness and chance of tumor recurrence; however they are not enough for prognosis definition. Thus, the discovery of new markers is essential to improve prognostication in order to previously identify the patients most likely to relapse; which may be candidates for adjuvant therapy. In this respect, great attention has been given to the molecular markers. Adhesion molecules are important for maintenance of the benign epithelial phenotype and changes of their expression seem to play a role in oncogenesis of several neoplasms. E-cadherin promotes strict adhesion between the epithelial cells while the P, N and OB-cadherin result in weak adhesion that leads to a loose and mesenchymal arrangement among epithelial cells, which facilitates tumor invasion. The switch of E-cadherin to other cadherins is a phenomenon called epithelial mesenchymal transition (EMT) and has been associated with poor prognosis in some tumors. The aim of this study is to evaluate the presence of EMT in the primary tumor, through the immunohistochemically analysis of expression of E, N, P and OB-cadherin in a "tissue micro array", previously established in our laboratory containing 111 primary tumors, and to correlate the occurrence of EMT with classical prognostic factors and biochemical recurrence after surgery. We will also evaluate the presence of EMT during prostate cancer progression by assessing the expression of these molecules in two "tissue microarray" containing 19 lymph node metastases and 28 bone metastases.