COULD MICRORNA ANALYSIS HELP IN THE APPROACH TO MEDULLARY THYROID CANCER?

AUTHORS:
B. Febrero (Murcia, Spain) , I. Ros-Madrid (Murcia, Spain) , B. Revilla (Murcia, Spain) , E. Iborra (Murcia, Spain) , J.J. Ruiz-Manzanera (Murcia, Spain) , M. Abellán (Murcia, Spain) , C. Muñoz (Murcia, Spain) , J.M. Rodríguez (Murcia, Spain)
Background:
In medullary thyroid carcinoma (MTC), calcitonin levels and TNM staging are the only established prognostic factors. On the other hand, the diagnostic yield of cytology for MTC is only found in about half of the cases, with only calcitonin levels being available for diagnosis. The expression of miRNAs could also help us in both diagnosis and surgical planning.
Methods:
Twenty-five patients with MTC were selected. The expression profiles of 5 miRNAs were analysed. The cDNA synthesis was carried out with the miRCURY LNA RT Kit. The gene expression study was performed by real-time PCR using the QuantStudio 5 kit. A descriptive analysis was performed on the relative expression of miRNAs and several variables. A comparative study was performed with parametric and non-parametric tests.
Results:
Of the 25 patients selected, 60% (n=15) were female, 56% (n=14) had familial MTC. Mean expression for miR-200c-3p, miR-144-3p, miR-34a-5p, miR183-5p and miR-375-5p were 1.17, 1.15, 1.20, 9.55, 3,687, respectively. When compared to healthy thyroid tissue, expression differences were found in miR183-5p and 375-5p (p=0.001). Patients with more disease-free interval showed higher expression of 200c-3p (p=0.456, p=0.022). Patients with persistence and recurrence showed a trend towards lower expression of 200c-3p (0.92 vs. 1.49; p=0.057).
Conclusions:
The determination of miRNAs in MTC could guide us in the extension of the surgery and follow-up of these patients. The expression of miRNA 183-5p and 375-5p could guide us to the diagnosis of MTC, and a lower expression of miRNA 200C-3p could guide us to a higher aggressiveness.