LncRNAMORT is upregulated in myocardial infarction and promotes the apoptosis of cardiomyocyte by downregulating miR-93

MiRNA-93: a novel signature in human disorders and drug resistance

miRNA-93 is a member of the miR-106b-25 family and is encoded by a gene on chromosome 7q22.1. They play a role in the etiology of various diseases, including cancer, Parkinson's disease, hepatic injury, osteoarthritis, acute myocardial infarction, atherosclerosis, rheumatoid arthritis, and chronic kidney disease. Different studies have found that this miRNA has opposing roles in the context of cancer. Recently, miRNA-93 has been downregulated in breast cancer, gastric cancer, colorectal cancer, pancreatic cancer, bladder cancer, cervical cancer, and renal cancer. However, miRNA-93 is up-regulated in a wide variety of malignancies, such as lung, colorectal, glioma, prostate, osteosarcoma, and hepatocellular carcinoma. The aim of the current review is to provide an overview of miRNA-93's function in cancer disorder progression and non-cancer disorders, with a focus on dysregulated signaling pathways. We also give an overview of this miRNA's function as a biomarker of prognosis in cancer and emphasize how it contributes to drug resistance based on in vivo, in vitro, and human studies. Video Abstract.

Targeting Epigenetics and Non-coding RNAs in Myocardial Infarction: From Mechanisms to Therapeutics

Myocardial infarction (MI) is a complicated pathology triggered by numerous environmental and genetic factors. Understanding the effect of epigenetic regulation mechanisms on the cardiovascular disease would advance the field and promote prophylactic methods targeting epigenetic mechanisms. Genetic screening guides individualised MI therapies and surveillance. The present review reported the latest development on the epigenetic regulation of MI in terms of DNA methylation, histone modifications, and microRNA-dependent MI mechanisms and the novel therapies based on epigenetics.

Long non-coding RNA LUCAT1 inhibits myocardial oxidative stress and apoptosis after myocardial infarction via targeting microRNA-181a-5p

This study hoped to explore the effects and mechanism of long non-coding RNA (lncRNA) LUCAT1 regulating microRNA-181a-5p (miR-181a-5p) on oxidative stress and apoptosis of cardiomyocytes induced by H₂O₂. Totally, 72 patients with acute myocardial infarction (AMI) were included. H9c2 cardiomyocytes were cultured in vitro, and the H₂O₂ model of cardiomyocytes was established. The expression levels of LUCAT1 and miR-181a-5p were detected by qRT-PCR after H₂O₂ induction. The contents of reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA) in cells were detected. The survival rate of the cells was detected by the Cell Counting Kit-8 (CCK-8) method; the apoptosis was detected by flow cytometry. The luciferase reporter experiment and quantitative real-time PCR (qRT-PCR) were used to verify the targeted relationship between LUCAT1 and miR-181a-5p. LUCAT1 was lowly expressed in the AMI patients. After H₂O₂ induction, the expression of LUCAT1 in H9c2 cells lessened significantly, while the expression of miR-181a-5p elevated significantly (P < 0.001). Transfection of p-LUCAT1 significantly reversed the decreased SOD levels, the increased MDA and ROS content, and the elevated tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) in H₂O₂-stimulated cells (P < 0.001). Upregulation of LUCAT1 contributed to the mitigation of H₂O₂ injury by promoting viable cells and repressing apoptotic cells (P < 0.01). LUCAT1 targeted miR-181a-5p and negatively regulated miR-181a-5p expression (P < 0.001). Collectively, LUCAT1 played a protective role on oxidative stress injury, inflammation, viability, and apoptosis of cardiomyocytes induced by H₂O₂ via regulating miR-181a-5p.

LncRNA MORT (ZNF667-AS1) in Cancer-Is There a Possible Role in Gynecological Malignancies?

Gynecological cancers (GCs) are currently among the major threats to female health. Moreover, there are different histologic subtypes of these cancers, which are defined as ‘rare’ due to an annual incidence of <6 per 100,000 women. The majority of these tend to be associated with a poor prognosis. Long non-coding RNAs (lncRNAs) play a critical role in the normal development of organisms as well as in tumorigenesis. LncRNAs can be classified into tumor suppressor genes or oncogenes, depending on their function within the cellular context and the signaling pathways in which they are involved. These regulatory RNAs are potential therapeutic targets for cancer due to their tissue and tumor specificity. However, there still needs to be a deeper understanding of the mechanisms by which lncRNAs are involved in the regulation of numerous biological functions in humans, both in normal health and disease. The lncRNA Mortal Obligate RNA Transcript (MORT; alias ZNF667-AS1) has been identified as a tumor-related lncRNA. ZNF667-AS1 gene, located in the human chromosome region 19q13.43, has been shown to be silenced by DNA hypermethylation in several cancers. In this review, we report on the biological functions of ZNF667-AS1 from recent studies and describe the regulatory functions of ZNF667-AS1 in human disease, including cancer. Furthermore, we discuss the emerging insights into the potential role of ZNF667-AS1 as a biomarker and novel therapeutic target in cancer, including GCs (ovarian, cervical, and endometrial cancers).

Knockdown of lncRNA Abhd11os attenuates myocardial ischemia/reperfusion injury by inhibiting apoptosis in cardiomyocytes

ABSTRACT

Long non-coding RNA (lncRNA) is one potential target for the treatment of various disorders. Here, we explored the role of Abhd11os in ischemia/reperfusion-induced myocardial injury, and preliminarily explored the regulatory mechanisms. Relative Abhd11os expression level was examined by qRT-PCR. Western blot was done to measure the expression of apoptotic-related proteins. CCK-8 assay and flow cytometry were performed to detect cell viability and apoptosis, respectively. ELISA assay was used to ensure the levels of LDH, CK, and cTnI in serum. Besides, the infarct sizes were confirmed by TTC and Evans blue staining. Apoptotic rate of cardiomyocytes in myocardial tissues was evaluated by TUNEL assay. Here, increased Abhd11os expression was found in rat myocardial ischemia/reperfusion injury (MIRI) model and hypoxia/reoxygenation (H/R)-treated cardiomyocytes. Subsequently, our data in vitro showed that upregulation of Abhd11os inhibited proliferation of cardiomyocytes, but promoted cell apoptosis. In animal experiments, myocardial infarct size in MIRI rats was reduced by Abhd11os knockdown. Moreover, downregulation of Abhd11os inhibited apoptosis of cardiomyocytes. Overall, our results revealed that knockdown of Abhd11os could notably attenuate H/R-induced myocardial injury through suppressing apoptosis of cardiomyocytes. These data suggest that Abhd11os may be a potential target for MIRI therapy.

Silencing CircHIPK3 Sponges miR-93-5p to Inhibit the Activation of Rac1/PI3K/AKT Pathway and Improves Myocardial Infarction-Induced Cardiac Dysfunction

The ceRNA network involving circular RNAs (circRNAs) is essential in the cardiovascular system. We investigated the underlying ceRNA network involving circHIPK3 in myocardial infarction (MI). After an MI model was established, cardiac function was verified, and myocardial tissue damage in mice with MI was evaluated. A hypoxia model of cardiomyocytes was used to simulate MI in vivo, and the expression of and targeting relationships among circHIPK3, miR-93-5p, and Rac1 were verified. The apoptosis of cardiomyocyte was identified. Gain- and loss-of-functions were performed to verify the ceRNA mechanism. The MI-modeled mice showed cardiac dysfunction and enlarged infarct size. CircHIPK3 was highly expressed in mouse and cell models of MI. Silencing circHIPK3 reduced infarct size, myocardial collagen deposition, and myocardial apoptosis rate and improved cardiac function. CircHIPK3 sponged miR-93-5p, and miR-93-5p targeted Rac1. Overexpression of miR-93-5p inhibited MI-induced cardiomyocyte injury and eliminated the harmful effect of circHIPK3. CircHIPK3 acted as ceRNA to absorb miR-93-5p, thus promoting the activation of the Rac1/PI3K/AKT pathway. We highlighted that silencing circHIPK3 can upregulate miR-93-5p and then inhibit the activation of Rac1/PI3K/Akt pathway, which can improve MI-induced cardiac dysfunction.

miR-19a mitigates hypoxia/reoxygenation-induced injury by depressing CCL20 and inactivating MAPK pathway in human embryonic cardiomyocytes

OBJECTIVE

Myocardial infarction (MI) is a prevalent cardiovascular puzzle and a mainspring of disease-induced mortality. We performed this investigation to detect the role of putative important miRNAs or genes in MI.

RESULTS

CCL20 may be a potential therapeutic target, which was directly targeted and negatively regulated by miR-19a. CCL20 expression was significantly increased in MI tissue samples, but miR-19a was expressed at lower levels in MI. H/R treatment inhibited cell viability and induced an increase of apoptotic rate compared with Sham group. However, miR-19a mimic relieved the H/R-stimulated injury to cardiomyocytes. Protective effect of miR-19a against H/R in cardiomyocytes was reversed by CCL20 enhancement, and MAPK pathway was inactivated during this progression.

CONCLUSIONS

miR-19a eliminates the H/R-induced injury in cardiomyocytes through directly targeting CCL20 and attenuating the activity of MAPK signaling pathway. These observations highlighted the therapeutic roles of miR-19a and CCL20 for MI treatment.