Aim- MicroRNA-183 cluster (miR-96/182/183) has been reported to have direct involvement in neural crest-derived tumours especially in SDHB mutated pheochromocytomas. This study aims to examine the expression profiles of miR-183 cluster in pheochromocytoma and its potential relevance to clinicopathological characteristics.
Materials and methods - Pheochromocytoma tissues were prospectively collected from 50 patients (28 men and 22women) who underwent resection of pheochromocytoma. MicroRNAs were extracted from these patients and converted to cDNA. MiR-183 cluster expressions were analysed by quantitative real-time polymerase chain reaction. The expression of miR-183 cluster members in pheochromocytomas was correlated with the clinical features, pathological parameters and SDHB protein expression of these patients.
Results- The relative expression levels of miR-183 cluster members were predominantly downregulated or deleted in pheochromocytomas. Among the cluster, low expression or deletion of miR-96 was predominantly noted in younger age patients with pheochromocytoma (<50 years, p=0.01). Female patients in the study group showed marked deletion of miR-182 (p=0.05). Deletion of the cluster was also associated with SDHB protein expression in pheochromocytomas. Moreover, patients with low miR-183 cluster expression had a slightly better survival rate when compared to patients with high expression of miR-183 cluster.
Conclusion- miR-183 cluster members have roles in the pathogenesis and clinical progression of pheochromocytoma. They could be potential prognostic markers in patients with pheochromocytoma.