Abstract
We investigated the expression profile of selected microRNAs (miRs) in serum and tissue samples from patients with sporadic parathyroid adenomas (sPAs). This was a prospective, controlled cohort study. Forty patients with sPAs who had undergone parathyroidectomy (PTX) were included. MiR extraction was performed from (i) 40 formalin-fixed paraffin-embedded samples (FFPEs) of sPAs, (ii) 10 FFPEs of normal parathyroid tissue (NPT), (iii) serum samples of the 40 patients with sPAs (t1 = baseline; t2 = 2 months post-PTX), and (vi) serum samples of 10 healthy individuals (controls; t1 = baseline and t2 = 2 months later). Ten miRs were selected based on their interaction with genes related to parathyroid tumorigenesis (miR-17-5p, miR-24-3p, miR-29b-3p, miR-31-5p, miR-135b-5p, miR-186-5p, miR-195-5p, miR-330-3p, miR-483-3p, and miR-877-5p). At tissue level, the relative expression of miR-17-5p, miR-31-5p, miR-135b-5p, miR-186-5p, and miR-330-3p was significantly decreased (fold change [FC]: 0.17, FC: 0.03, FC: 0.01, FC: 0.10, FC: 0.10, respectively; all p values <0.001), and the expression of miR-24-3p and miR-29b-3p was significantly increased (FC: 12.4, p < 0.001; FC: 18.5, p = 0.011, respectively) in sPA compared with NPT samples. The relative expression of miR-135b-5p was also significantly decreased in the serum samples of patients compared with controls (FC: 0.7, p = 0.035). No significant differences were found in the serum samples of patients before and after PTX. MiRs that regulate genes linked to parathyroid tumors such as menin 1 (miR-24-3p, miR-29b-3p), cyclin D1 (miR-17-5p), calcium sensing receptor (miR-31-5p, miR-135b-5p), cyclin-dependent kinase inhibitors (miR-186-5p), and β-catenin (miR-330-3p) were significantly deregulated in sPAs compared with NPT samples, suggesting a role for epigenetic changes in parathyroid tumorigenesis. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.