Dados do Trabalho

Título

Evaluation of microRNA expression in metastatic and non-metastatic mucoepidermoid carcinoma

Introdução

Mucoepidermoid carcinoma (MEC) is the most frequent malignant neoplasm in salivary gland tumors, mainly in the parotid gland. Metastasis can occur in the lymph nodes or at distant sites. MicroRNAs (miRNA), small non-coding RNAs involved in the post-transcriptional regulation of target mRNAs, described as possible biomarkers of different tumors. Previous study from our group evaluated the differential expression of miRNAs in MEC samples using a panel of 377 miRNAs and identified 45 differentially expressed miRNAs that may be related with the metastatic potential of these tumors.

Objetivo

The aim of the present study is the confirmation of the differential expression of miRNAs expressed in mucoepidermoid carcinoma samples and the determination of the target messenger RNAs of these miRNAs, associating their expression with clinical and pathological characteristics of the tumors.

Métodos

Mucoepidermoid carcinoma samples - metastatic, non-metastatic, and with unknown metastatic status – is being analyzed using real time RT-PCR technique. The expression level of the miRNAs is quantified relative to the expression of a reference miRNAs and is normalized according to a calibrator sample (pool of non-neoplastic salivary glands tissue samples). The result it is expressed as the increase or decrease of the expression of a microRNA in n-times when compared to the calibrator sample.
The project was approved by the CEP (no. 2700/19).

Resultados

In the first stage of the project, we confirmed the expression of miRNAs in MEC samples by comparing them with the expression obtained in the profile of the previous study. A set of 7 miRNAs was analyzed in 7 samples. Considering non-neoplastic samples versus lymph node metastasis, 2 miRNAs showed expression equivalent to the observed in the profile, confirming their differential expression in samples with lymph node metastasis. The comparison between non-neoplastic and distant metastatic samples resulted in one miRNA in agreement with the profile. Regarding non-neoplastic versus non-metastatic and non-metastatic versus lymph node metastasis, miRNA expression was not in accordance with the observed in the profile. Thus, in this step we were able to confirm the differential expression of 3 miRNAs.
In the second stage of the project, we are evaluating the expression of these 3 confirmed miRNAs in 19 different MEC samples. The demographic, clinical and pathological characteristics of these samples are being collected in the medical archives. So far, we collected data from 7 patients in order to compare these data with miRNA expression.

Conclusões

In the present study, it was possible to identify microRNAs associated with metastatic potential in mucoepidermoid carcinoma. Profiling the miRNA in MEC could provide a better understanding of the molecular basis of the lesions and better targeting of treatment in patients with more or less aggressive profiles of the disease profiles.

Palavras-chave

MicroRNAs, mucoepidermoid, metastasis.