MiR-3646 accelerates inflammatory response of Ang II-induced hVSMCs via CYP2J2/EETs axis in hypertension model

BACKGROUND

Inflammatory response of human vascular smooth muscle cells (hVSMCs) is a driving factor in hypertension progression. It has been reported that miR-3646 was significantly up-regulated in serum samples from patients with coronary artery disease and acute myocardial infarction mice. However, its role and underlying molecular mechanism related to inflammatory response of angiotensin II (Ang II)-induced hVSMCs remain unclear.

OBJECTIVE

We aimed to explore the potential molecular mechanisms related to inflammatory response of angiotensin II (Ang II)-induced hVSMCs.

METHODS

Ang II-induced hypertension model was established after hVSMCs treated with 1 μM Ang II at 24 h. The interaction between microRNA 3646 (miR-3646) and cytochrome P450 2J2 (CYP2J2) was assessed by dual-luciferase reporter gene assay. MTS assay, Lipid Peroxidation MDA Assay Kit, ELISA, Western blot, and qRT-PCR were performed to examine viability, malondialdehyde (MDA) level, inflammatory cytokine levels, and the level of genes and proteins.

RESULTS

Our findings illustrated that miR-3646 was up-regulated but CYP2J2 was down-regulated in Ang II-induced hVSMCs. Mechanically, miR-3646 negatively targeted to CYP2J2 in Ang II-induced hVSMCs. These findings indicated that miR-3646 regulated inflammatory response of Ang II-induced hVSMCs via targeting CYP2J2. Moreover, functional researches showed that CYP2J2 overexpression alleviated inflammatory response of Ang II-induced hVSMCs via epoxyeicosatrienoic acids/peroxisome proliferator-activated receptor-γ (EETs/PPARγ) axis, and miR-3646 aggravated inflammatory response of Ang II-induced hVSMCs via mediating CYP2J2/EETs axis.

CONCLUSION

MiR-3646 accelerated inflammatory response of Ang II-induced hVSMCs via CYP2J2/EETs axis. Our findings illustrated the specific molecular mechanism of miR-3646 regulating hypertension.

MicroRNA miR-3646 promotes malignancy of lung adenocarcinoma cells by suppressing sorbin and SH3 domain-containing protein 1 via the c-Jun NH2-terminal kinase signaling pathway

Lung adenocarcinoma (LUAD) is a highly malignant tumor. In this study, we examined the role of miR-3646 and its underlying mechanism in the progression of LUAD. The expression of miR-3646 and sorbin and SH3 domain-containing protein 1 (SORBS1) in LUAD tissues and cells was evaluated by quantitative reverse transcription-polymerase chain reaction. LUAD cell adhesion, proliferation, apoptosis was determined. The targeting relationship between SORBS1 and miR-3646 was verified by dual luciferase and RNA pull-down assays. In vivo assays were performed to verify the in vitro results. The expression of miR-3646 was found to be upregulated in LUAD tissues and cells. MiR-3646 overexpression stimulated the proliferation and adhesion of LUAD cells but inhibite d apoptosis, whereas a miR-3646 inhibitor produced the opposite results. Furthermore, the inhibitory effect of miR-3646 inhibitor was verified in vivo. SORBS1, a target gene identified downstream of miR-3646, was downregulated in LUAD tissues and cells. Additionally, increased SORBS1 inhibited the malignant phenotypes of LUAD cells, which was restored by miR-3646 upregulation. Additionally, western blot analysis revealed that SORBS1 ectopic expression disrupted the JNK signaling pathway, and this effect was restored by miR-3646 overexpression. Thus, this study revealed that miR-3646 promotes LUAD cell proliferation and adhesion, and reduces apoptosis by directly downregulating SORBS1 via the JNK signaling pathway. Investigation of the molecular mechanism of LUAD carcinogenesis revealed that miR-3646 may serve as a biomarker for LUAD treatment.in vivo

microRNA-3646 serves as a diagnostic marker and mediates the inflammatory response induced by acute coronary syndrome

Acute coronary syndrome (ACS) is one of the main syndromes of coronary artery disease with high mortality. The identification of biomarkers associated with disease occurrence and progression could improve early detection and risk prediction. This study was aimed to reveal the clinical significance and function of miR-3646 in ACS.

The expression of miR-3646 was evaluated in ACS patients, healthy volunteers, and non-ACS patients and estimated the clinical significance of miR-3646. The ACS modeling rats were also established in this study to explore the potential mechanism underlying the function of miR-3646. miR-3646 was upregulated in ACS patients compared with healthy volunteers and non-ACS patients. The expression of miR-3646 was positively correlated with the severity and progression of ACS patients and could discriminate ACS patients from healthy volunteers and non-ACS patients. The knockdown of miR-3646 could reverse the inflammatory response induced by ACS.miR-3646 serves as a diagnostic biomarker for ACS. The knockdown of miR-3646 could alleviate ACS by reversing inflammatory response. These results provide a potential therapeutic target of ACS.

miR-3646 promotes vascular inflammation and augments vascular smooth muscle cell proliferation and migration in progression of coronary artery disease by directly targeting RHOH

Coronary artery disease (CAD) is one of the leading causes of mortality and morbidity worldwide and the number of individuals at CAD risk is increasing. To better manage cardiovascular disease, improved tools for risk prediction including the identification of novel accurate biomarkers are needed. MicroRNAs (miRNAs) are small non-coding RNAs that modulate the expression of protein-coding genes at the post-transcription level and their dysregulated expression has been implicated in various pathogenic processes including cardiovascular disease. Circulating miRNAs have been widely recommended as potential biomarkers for many diseases including coronary artery disease. In the present study, we found that miR-3646 was significantly upregulated in the serum samples of CAD patients and in the mice with acute myocardial infarction (AMI) compared with the healthy control group via using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Moreover, the serum levels of miR-3646 were significantly positively correlated with the expression of IL-6 both in CAD patient samples and AMI mice samples. In human THP-1 macrophages, transfection with miR-3646 mimic elevated the expression of IL-6 while silence of miR-3646 suppressed the IL-6 level. Further exploration of the downstream targets of miR-3646 identified that blocking RHOH expression also could upregulate IL-6 expression. In addition, our findings also showed that miR-3646 promoted vascular smooth muscle cell (VSMC) proliferation and migration by targeting RHOH. These results demonstrate that the miR-3646-RHOH axis may serve as a key regulator in the progression of CAD by modulating vascular inflammation and regulating the biologic behaviors of VSMCs.

miR-3646 promotes cell proliferation, migration, and invasion via regulating G2/M transition in human breast cancer cells

MicroRNAs (miRNAs) are small non-coding RNAs that are often located in genomic breakpoint regions and play a critical role in regulating a variety of the cellular processes in human cancer. miR-3646 has been reported to take part in tumorigenic progression in breast and bladder cancer, but its potential functions and exact mechanistic roles in breast cancer are still unclear. The objective of this study was to investigate the role of miR-3646 in breast cancer growth and metastasis using both bioinformatic and experimental approaches. Before starting the bench work, we conducted a bioinformatic study to predict the target genes regulated by miR-3646 using a panel of different algorithms. The results showed that miR-3646 might regulate a large number of genes that are related to cell growth, proliferation, metabolis, transport, and apoptosis and some were cancer-related genes. We found that the expression level of miR-3646 was significantly upregulated in breast cancer cells and tissues compared with normal breast cells and no tumor tissues. Subsequently, the MTT and colony formation assay results showed that up-regulation of miR-3646 promoted the cell viability and proliferation. Our results also showed that down-regulation of miR-3646 arrested the cells in G2/M phase in MCF7 and MDA-MB-231 cells which was accompanied by the down-regulation of CDK1/CDC2 and cyclin B1 and upregulation of p21Waf1/Cip1, p27 Kip1, and p53, suggesting that down-regulation of miR-3646 induces G2/M arrest through activation of the p53/p21/CDC2/cyclin B1 pathway. In addition, overexpression of miR-3646 promoted migration and invasion of MCF7 and MDA-MB-231 cells. Taken together, miR-3646 is a potential oncogene in breast cancer and it may represent a new niomarker in the diagnosis and prediction of prognosis and therapeutic response.