Identification and validation of tumor markers with clinical application in veterinary oncology practice

Abstract

Veterinary oncology has grown in Brazil and in the world, and with advances in diagnosis, several molecular tests have been indicated for patients with different neoplasms. However, in Brazil, only one laboratory offers molecular tests applied to routine oncology. A major limitation of the use of these markers is the fact that they are tested on cutting-edge platforms, using expensive techniques, which, due to their high cost, have low adherence in the market. Therefore, different efforts have been made to reduce the costs of detecting these markers. To request this proposal, a market research was carried out to understand the need of the national market for the different markers within veterinary oncology. In this survey, 60% of the veterinarians who responded confirmed that they routinely request these exams, and of the approximately 40% that do not request them, most face the cost of the exam. Therefore, we investigated which would be the tumors with the greatest need for new markers in the national market and identified that oral melanoma, mast cell tumors and osteosarcoma are tumors that need new prognostic markers. Thus, a search was carried out in the international literature, and the respective markers with proven prognostic potential were identified, and we proposed their evaluation by less expensive techniques, for a translational application. For canine oral melanoma, the traditional PCR evaluation of the CFA30 chromosome, and the immunohistochemical evaluation of BUB-1 and TRPM7 were selected. For canine cutaneous mast cell tumors, PCR was selected to identify the PTEN deletion by traditional PCR and immunohistochemistry for PTEN. For canine osteosarcoma, the PTEN and HER-2 genes were selected to be evaluated by traditional PCR and immunohistochemistry. The gold standard technique in the literature will be performed in parallel for the validation of the respective tests, and it is expected to find corresponding results in the less expensive techniques proposed. For data analysis, the clinical data of the patients, gene expression by PCR and by immunohistochemistry will be taken into consideration. Thus, univariate and multivariate analyzes will be performed to assess the prognostic value of each of the markers. In addition, comparative analyzes of sensitivity and specificity of each test will be performed to ensure their validated clinical applications. At the end of this research, the traditional PCR and immunohistochemical techniques are expected to be validated as techniques with valid prognostic value, for application in veterinary oncological molecular diagnosis. (AU)