Purpose: The aim of this preliminary study was to analyze and identify differentially expressed miRNAs in Bulgarian patients with non-functioning pituitary neuroendocrine tumors (NFPitNET). The relationship between deregulated miRNAs and tumor invasiveness, recurrence, and size was determined.
Methods: Twenty patients with non-functioning pituitary neuroendocrine tumors were selected and fresh pituitary tumor tissues were collected. RNA containing miRNAs were isolated using miRNAeasy mini kit and analysed with LNA miRNA Cancer Focus PCR Panel (Qiagen) by quantitative real-time PCR.
Results: Three miRNAs (miR-210-3p, miR-149-3p and miR-29b-3p) were deregulated in invasive compared to non-invasive NFPitNETs. Differential expression of four-miRNA signature - miRNA-17, miR-19, miR-106a and miR-20, correlated with patient recurrence.
Conclusion: In this pilot prospective study, we selected a unique miRNA expression profile that correlates with invasiveness and recurrence in non-functioning pituitary neuroendocrine tumors. Moreover, some of the selected miRNAs are reported for the first time in patients with this disease, shedding light on the molecular mechanisms involved in pituitary pathogenesis. The identified miRNAs demonstrate potential as biomarkers, deserving further investigation in a larger cohort to validate their clinical applicability.