miR-3156-5p is downregulated in serum of MEN1 patients and regulates expression of MORF4L2

Abstract

Multiple endocrine neoplasia type 1 (MEN1), caused by mutations in the MEN1 gene encoding menin, is an autosomal dominant disorder characterised by the combined occurrence of parathyroid, pituitary and pancreatic neuroendocrine tumours (NETs). Development of these tumours is associated with wide variations in their severity, order and ages (from <5 to >80 years), such that life-long screening is required. To improve tumour surveillance and quality of life, better circulating biomarkers, particularly for pancreatic NETs that are associated with a higher mortality, are required. We therefore examined the expression of circulating microRNAs (miRNAs) in serum of MEN1 patients. Initial profiling analysis followed by qRT-PCR validation studies identified miR-3156-5p to be significantly downregulated (-1.3-5.8-fold, p<0.05-0.0005) in 9 MEN1 patients, compared to matched unaffected relatives. MEN1 knock-down experiments in BON-1 human pancreatic NET cells resulted in reduced MEN1 (49%, p<0.05), menin (54%, p<0.05) and miR-3156-5p expression (20%, p<0.005), compared to control-treated cells, suggesting that miR-3156-5p downregulation is a consequence of loss of MEN1 expression. In silico analysis identified mortality factor 4 like 2 (MOR4FL2) as a potential target of miR-3156-5p, and in vitro functional studies in BON-1 cells transfected with either miR-3156-5p mimic or inhibitors showed that the miR-3156-5p mimic significantly reduced MORF4L2 protein expression (46%, p<0.005), while miR-3156-5p inhibitor significantly increased MORF4L2 expression (1.5-fold, p<0.05), compared to control treated cells, thereby confirming that miR-3156-5p regulates MORF4L2 expression. Thus, the inverse relationship between miR-3156-5p and MORF4L2 expression represents a potential serum biomarker that could facilitate the detection of NET occurrence in MEN1 patients.

Plasma miRNA expression in patients with genetically confirmed multiple endocrine neoplasia type 1 syndrome and its phenocopies

“…и ­соавт. [ 23 ]. В их исследовании анализ экспрессии циркулирующих микроРНК производился методом NGS с последующей валидацией методом qRT-PCR, по результатам которого было выявлено, что экспрессия miR-3156-5p значительно снижена у пациентов с гМЭН-1, чем у их родственников.…”

Regulatory mechanisms of microRNAs in endocrine disorders and their therapeutic potential

“…Moreover, a significant downregulation of miR-3156-5p was observed in serum samples of MEN1 patients compared to controls. This downregulation may be the result of a reduction in MEN1 expression (Kooblall et al, 2022). It was also found that miR-3156-5p directly targets MORF4L2, given that miR-3156-5p upregulation causes a decrease of MORF4L2 expression, which plays an important role in the activation of oncogene and protooncogene-mediated growth induction, as well as in tumor suppressor-mediated growth arrest.…”

“…It was also found that miR-3156-5p directly targets MORF4L2, given that miR-3156-5p upregulation causes a decrease of MORF4L2 expression, which plays an important role in the activation of oncogene and protooncogene-mediated growth induction, as well as in tumor suppressor-mediated growth arrest. Additionally, MORF4L2 is part of the NETest, a useful tool for neuroendocrine tumor (NET) subtype management and diagnosis, therefore, it might be of utility for MEN1 diagnosis (Kooblall et al, 2022).…”

Regulatory mechanisms of microRNAs in endocrine disorders and their therapeutic potential

“…Moreover, a significant downregulation of miR-3156-5p was observed in serum samples of MEN1 patients compared to controls. This downregulation may be the result of a reduction in MEN1 expression ( Kooblall et al, 2022 ). It was also found that miR-3156-5p directly targets MORF4L2, given that miR-3156-5p upregulation causes a decrease of MORF4L2 expression, which plays an important role in the activation of oncogene and proto-oncogene-mediated growth induction, as well as in tumor suppressor-mediated growth arrest.…”

“…It was also found that miR-3156-5p directly targets MORF4L2, given that miR-3156-5p upregulation causes a decrease of MORF4L2 expression, which plays an important role in the activation of oncogene and proto-oncogene-mediated growth induction, as well as in tumor suppressor-mediated growth arrest. Additionally, MORF4L2 is part of the NETest, a useful tool for neuroendocrine tumor (NET) subtype management and diagnosis, therefore, it might be of utility for MEN1 diagnosis ( Kooblall et al, 2022 ).…”