Circulating miR-29c-3p is downregulated in patients with acromegaly

miRNAs control various biological functions, such as cell proliferation, differentiation, signaling pathways, apoptosis and metabolism. Recently, it has been shown that there is a relationship between changes in miRNA expression and the development of acromegaly. Studies are needed to identify new disease-specific miRNAs. The aim of the current study is to evaluate plasma miR-29c-3p, miR-31-5p and miR-18a-5p steady-state levels in acromegaly. Another aim is to investigate whether there is a difference in the levels of these miRNAs in patients with inadequate control and controlled acromegaly with somatostatin analog (SSA) therapy. These miRNAs targeting the IGF-1 gene were determined by in silico estimation.

The study included 30 healthy controls (HC) and 20 patients with acromegaly. Anterior pituitary functions and disease activities of patients with acromegaly were evaluated at the time of study. The miR-29c-3p, miR-31-5p and miR-18a-5p levels were measured using quantitative real-time PCR (RT-qPCR).

The expression level of miR-29c-3p was significantly lower in patients with acromegaly compared to the HC group (p < 0.001). This downregulation was more pronounced in patients with inadequately controlled acromegaly than in patients with acromegaly controlled with somatostatin analogues (SSA) therapy (p = 0.016). Univariate logistic regression analysis results showed that down regulation of miR-29c-3p expression increases the risk of developing acromegaly [OR (95% Cl) = 1.605 (1.142-2.257), p = 0.006]. There was no significant difference between the groups in terms of miR-31-5p and miR-18a-5p expression levels (p = 0.375 and p = 0.649, respectively).

Plasma miR-29c-3p expression level is downregulated in patients with acromegaly, and this is more pronounced in patients with inadequate control.