Verification of saliva proteins candidates for OSCC markers and their correlation with prognosis

Author(s)

Tatiane De Rossi

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia
• Defense date: 2019-08-28

Examining board members

Adriana Franco Paes Leme; Fabio Albuquerque Marchi; Nilva de Karla Cervigne; André Zelanis Palitot Pereira; Marcio Chaim Bajgelman

• Advisor: Adriana Franco Paes Leme

Abstract

The most prevalent oral cancer worldwide is squamous cell carcinoma (OSCC), accounting for over 90% of all cases of oral cavity cancer. It is the sixth most common cancer in the worldwide, with 355,000 new cases a year. The most widely used prognostic factor is the clinical staging of disease, based on the classification of TNM, and the presence of lymph node metastasis is associated with poor prognosis. However, this classification system is not perfect, mainly because tumors with similar morphology and stages present different behaviors due to their distinct outcome. Thus, there is a need to find specific markers to predict the prognosis, allowing the increase in overall survival of these patients. The discovery that in saliva there are molecular profiles indicating systemic diseases favored the development of a new perspective of noninvasive diagnosis and prognosis. Thus, the hypothesis of this study was that the relative quantitation of the abundance of targeted proteins in the saliva of patients with OSCC can be correlated with the prognosis. To test this hypothesis, 40 saliva samples from patients with OSCC with or without lymph node metastasis were randomized and analyzed in blocks in triplicates using the selected reaction monitoring (SRM) method. 64 proteins of interest were selected and the proteotypic peptides synthesized for reference. Raw files were analyzed using the Skyline software and the results show that 33 proteins are differentially abundant in the lymph node metastasis group compared to the non-metastasis group by the Wilcoxon Mann-Whitney test corrected by FDR (p<0.05). Five peptides of five proteins were selected by different machine learning algorithms for 'absolute' quantitation using targeted-based proteomics. The data obtained in this study have prognostic value and complement the prognosis and clinical decision, allowing the assessment of the risk profile of patients with OSCC and guide therapeutic intervention strategies (AU)

• FAPESP's process: 15/12431-1 - Verification of saliva proteins candidates for markers in OSCC and its correlation with prognosis
• Grantee: Tatiane de Rossi Mazo
• Support Opportunities: Scholarships in Brazil - Doctorate