miRNAs in the Expression Regulation of Dopamine-Related Genes and Proteins in Endometrial Cancer

MicroRNA ame-let-7 targets Amdop2 to increase sucrose sensitivity in honey bees (Apis mellifera)

BACKGROUND

As an important catecholamine neurotransmitter in invertebrates and vertebrates, dopamine plays multiple roles in the life of the honey bee. Dopamine receptors (DA), which specifically bind to dopamine to activate downstream cascades, have been reported to be involved in honey bee reproduction, division of labour, as well as learning and motor behaviour. However, how dopamine receptors regulate honey bee behavior remains uninvestigated.

RESULTS

The expression level of Amdop2 in the brain increased with the age of worker bees, which was just the opposite trend of ame-let-7. Inhibition of ame-let-7 through feeding an inhibitor upregulated Amdop2 expression; conversely, overexpression of ame-let-7 through a mimic downregulated Amdop2. Moreover, knockdown of Amdop2 in forager brain led to significantly higher sucrose responsiveness, which is similar to the phenotype of overexpression of ame-let-7. Finally, we confirmed that ame-let-7 directly targets Amdop2 in vitro by a luciferase reporter assay.

CONCLUSIONS

ame-let-7 is involved in the dopamine receptor signaling pathway to modulate the sucrose sensitivity in honey bees. Specifically, it down-regulates Amdop2, which then induces higher responses to sucrose. These results further unraveled the diverse mechanisms of the dopamine pathway in the regulation of insect behavior.

Dopamine receptors gene overexpression in the microenvironment of invasive gastric cancer and its potential implications

BACKGROUND

Gastric cancer (GC) is the fifth most common cancer worldwide and the most commonly diagnosed cancer in Iran. The nervous system provides proximity to tumor cells by releasing neurotransmitters such as dopamine and presenting them to the corresponding receptor-bearing tumors. While nerve fibers infiltrate the tumor microenvironment, little is known about the expression levels of dopamine (DA), dopamine receptors (DRs), and catechol-O-methyltransferase (COMT) in GC patients.

METHODS

DRs and COMT expression were analyzed in 45 peripheral blood mononuclear cells (PBMCs) and 20 paired tumor and adjacent tissue of GC patients by quantitative polymerase chain reaction. DA was measured in plasma specimens using enzyme-linked immunosorbent assay. Protein-protein interaction analysis was carried out to identify GC-related hub genes.

RESULTS

Increased expression of DRD1-DRD3 was found in tumor specimens compared with adjacent non-cancerous specimens (P < 0.05). A positive correlation was found between DRD1 and DRD3 expression (P = 0.009); DRD2 and DRD3 expression (P = 0.04). Plasma levels of dopamine were significantly lower in patients (1298 pg/ml) than in controls (4651 pg/ml). DRD1-DRD4 and COMT were up-regulated in PBMCs of patients compared with controls (P < 0.0001). Bioinformatic analyses showed 30 hub genes associated with Protein kinase A and extracellular signal-regulated kinase signaling pathways.

CONCLUSIONS

The findings indicated dysregulation of DRs and COMT mRNA expression in GC and suggest that the brain- gastrointestinal axis may mediate gastric cancer development. Network analysis revealed that combination treatments could be considered for optimizing and improving the precision treatment of GC.

Inhibition of miR-4640-5p alleviates pulmonary hypertension in chronic obstructive pulmonary disease patients by regulating nitric oxide synthase 1

BACKGROUND

Pulmonary hypertension (PH) is a devastating disease characterized by vasoconstriction and vascular remodeling, leading to right ventricular failure and death. PH is a common complication of chronic obstructive pulmonary disease (COPD). Accumulating evidence demonstrate that microRNAs participate in the pathobiology of PH in COPD patients. In this study, we aimed to evaluate the expression and function of microRNA-4640-5p (miR-4640-5p) in PH.

METHODS

The mRNA and protein levels were determined by quantitative polymerase chain reaction (qPCR) and western blot, separately. Functional assays and western blot were performed to determine the effects of miR-4640-5p and NOS1 on cell growth, migration. Besides, the dual-luciferase reporter assays were used to validate miR-4640-5p and NOS1 interactions.

RESULTS

We found that miR-4640-5p expression was significantly higher in the lung tissues of COPD-PH patients than in the healthy controls while higher expression of miR-4640-5p was correlated with more severe COPD-PH. By using pulmonary artery smooth muscle cell (PASMC) in in vitro assays, we demonstrated that inhibition of miR-4640-5p suppressed cell proliferation and migration of PASMC via regulating mTOR/S6 signaling. Bioinformatics analysis and validation experiments revealed that nitric oxide synthase 1 (NOS1) was a direct downstream target of miR-4640-5p. Overexpression of NOS1 partially antagonized the effect of miR-4640-5p in regulating PASMC cell proliferation and migration. In addition, our findings suggested that miR-4640-5p/NOS1 axis regulated mitochondrial dynamics in PASMCs. Furthermore, in the hypoxia-induced PH rat model, inhibition of miR-4640-5p ameliorated PH with reduced right ventricular systolic pressure and Fulton index.

CONCLUSIONS

miR-4640-5p regulates PH via targeting NOS1, which provides a potential diagnostic biomarker and therapeutic target for COPD-PH patients.

The interplay of sex steroid hormones and microRNAs in endometrial cancer: current understanding and future directions

Introduction

Endometrial cancer is a hormone-dependent malignancy, and sex steroid hormones play a crucial role in its pathogenesis. Recent studies have demonstrated that microRNAs (miRNAs) can regulate the expression of sex steroid hormone receptors and modulate hormone signaling pathways. Our aim is to provide an overview of the current understanding of the role of miRNAs in endometrial cancer regulated by sex steroid hormone pathways.

Methods

A thorough literature search was carried out in the PubMed database. The articles published from 2018 to the present were included. Keywords related to miRNAs, endometrial cancer, and sex steroid hormones were used in the search.

Results

Dysregulation of miRNAs has been linked to abnormal sex steroid hormone signaling and the development of endometrial cancer. Various miRNAs have been identified as modulators of estrogen and progesterone receptor expression, and the miRNA expression profile has been shown to be a predictor of response to hormone therapy. Additionally, specific miRNAs have been implicated in the regulation of genes involved in hormone-related signaling pathways, such as the PI3K/Akt/mTOR and MAPK/ERK pathways.

Conclusion

The regulation of sex steroid hormones by miRNAs is a promising area of research in endometrial cancer. Future studies should focus on elucidating the functional roles of specific miRNAs in sex steroid hormone signaling and identifying novel miRNA targets for hormone therapy in endometrial cancer management.