Abstract 2999: Evaluation of microRNA expression in metastatic and non-metastatic salivary gland mucoepidermoid carcinoma

Abstract

Abstract Salivary gland tumors are a heterogeneous group of lesions, being mucoepidermoid carcinoma (MEC) the malignant neoplasm with the highest incidence, occurring mainly in the parotid gland. Characterization of its histological grade (high, intermediate, and low) is important for determining patient prognosis. Metastasis is more common high-grade tumors and can occur at regional lymph nodes or distant sites. Although the mechanisms underlying the metastatic process are largely unknown, large-scale microRNA expression profiling studies of human cancers have demonstrated that dysregulation of miRNA is frequently associated with many cancer types. The aim of this study is to validate the use of microRNA expression for the discrimination of the metastatic potential of MEC samples. Using Real Time RT-PCR (qPCR) we have analyzed the expression of 384 miRNAs and controls in 4 non-metastatic MECs, 3 MECs with lymph node metastasis, 3 MECs with distant metastasis, and 2 non-neoplastic human salivary gland samples. Comparing the expression among these groups we identified 45 differentially expressed miRNAs that may be related with the metastatic potential of these tumors. To validate the microRNA expression associated with the metastatic potential, we selected 7 out of the 45 differentially expressed microRNAs and 7 MEC samples from the different groups of samples. Considering the 7 microRNAs evaluated, we validated that the expression of miR-191 was increased in non-neoplastic samples when compared to MECs with lymph node metastasis and the expression of miR-494 was increased in non-neoplastic samples when compared to MECs with distant metastasis, suggesting that loss of these microRNAs might be involved in the development of metastasis in mucoepidermoid carcinoma. The determination of a miRNA expression profile could provide a better understanding of the molecular basis of MEC and facilitate the determination of diagnosis and prognosis of patients. Citation Format: Maria E. Trevizani, Katia K. Oliveira, Fabio A. Marchi, Daniela Bizinelli, Fernanda V. Mariano, Cibele P. Nagano, Felipe A. Costa, Clovis A. Pinto, Luiz P. Kowalski, Silvia V. Lourenço, Cláudia M. Coutinho-Camillo. Evaluation of microRNA expression in metastatic and non-metastatic salivary gland mucoepidermoid carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2999.