Inhibition of MicroRNA-149-5p Induces Apoptosis of Acute Myeloid Leukemia Cell Line THP-1 by Targeting Fas Ligand (FASLG)

Identification of necroptosis-related genes in ankylosing spondylitis by bioinformatics and experimental validation

The pathogenesis of ankylosing spondylitis (AS) remains unclear, and while recent studies have implicated necroptosis in various autoimmune diseases, an investigation of its relationship with AS has not been reported. In this study, we utilized the Gene Expression Omnibus database to compare gene expressions between AS patients and healthy controls, identifying 18 differentially expressed necroptosis-related genes (DENRGs), with 8 upregulated and 10 downregulated. Through the application of three machine learning algorithms-least absolute shrinkage and selection operation, support vector machine-recursive feature elimination and random forest-two hub genes, FASLG and TARDBP, were pinpointed. These genes demonstrated high specificity and sensitivity for AS diagnosis, as evidenced by receiver operating characteristic curve analysis. These findings were further supported by external datasets and cellular experiments, which confirmed the downregulation of FASLG and upregulation of TARDBP in AS patients. Immune cell infiltration analysis suggested that CD4+ T cells, CD8+ T cells, NK cells and neutrophils may be associated with the development of AS. Notably, in the group with high FASLG expression, there was a significant infiltration of CD8+ T cells, memory-activated CD4+ T cells and resting NK cells, with relatively less infiltration of memory-resting CD4+ T cells and neutrophils. Conversely, in the group with high TARDBP expression, there was enhanced infiltration of naïve CD4+ T cells and M0 macrophages, with a reduced presence of memory-resting CD4+ T cells. In summary, FASLG and TARDBP may contribute to AS pathogenesis by regulating the immune microenvironment and immune-related signalling pathways. These findings offer new insights into the molecular mechanisms of AS and suggest potential new targets for therapeutic strategies.

Non-coding RNAs in leukemia drug resistance: new perspectives on molecular mechanisms and signaling pathways

Like almost all cancer types, timely diagnosis is needed for leukemias to be effectively cured. Drug efflux, attenuated drug uptake, altered drug metabolism, and epigenetic alterations are just several of the key mechanisms by which drug resistance develops. All of these mechanisms are orchestrated by up- and downregulators, in which non-coding RNAs (ncRNAs) do not encode specific proteins in most cases; albeit, some of them have been found to exhibit the potential for protein-coding. Notwithstanding, ncRNAs are chiefly known for their contribution to the regulation of physiological processes, as well as the pathological ones, such as cell proliferation, apoptosis, and immune responses. Specifically, in the case of leukemia chemo-resistance, ncRNAs have been recognized to be responsible for modulating the initiation and progression of drug resistance. Herein, we comprehensively reviewed the role of ncRNAs, specifically its effect on molecular mechanisms and signaling pathways, in the development of leukemia drug resistance.

Necroptosis pathway emerged as potential diagnosis markers in spinal cord injury

The present research focused on identifying necroptosis-related differentially expressed genes (NRDEGs) in spinal cord injury (SCI) to highlight potential therapeutic and prognostic target genes in clinical SCI. Three SCI-related datasets were downloaded, including GSE151371, GSE5296 and GSE47681. MSigDB and KEGG datasets were searched for necroptosis-related genes (NRGs). Differentially expressed genes (DEGs) and NRGs were intersected to obtain NRDEGs. The MCC algorithm was employed to select the first 10 genes as hub genes. A protein-protein interaction (PPI) network related to NRDEGs was developed utilizing STRING. Several databases were searched to predict interactions between hub genes and miRNAs, transcription factors, potential drugs, and small molecules. Immunoassays were performed to identify DEGs using CIBERSORTx. Additionally, qRT-PCR was carried out to verify NRDEGs in an animal model of SCI. Combined analysis of all datasets identified 15 co-expressed DEGs and NRGs. GO and KEGG pathway analyses highlighted DEGs mostly belonged to pathways associated with necroptosis and apoptosis. Hub gene expression analysis showed high accuracy in SCI diagnosis was associated with the expression of CHMP7 and FADD. A total of two hub genes, i.e. CHMP7, FADD, were considered potential targets for SCI therapy.

Epithelial-Mesenchymal Transition in Acute Leukemias

Epithelial-mesenchymal transition (EMT) is a metabolic process that confers phenotypic flexibility to cells and the ability to adapt to new functions. This transition is critical during embryogenesis and is required for the differentiation of many tissues and organs. EMT can also be induced in advanced-stage cancers, leading to further malignant behavior and chemotherapy resistance, resulting in an unfavorable prognosis for patients. Although EMT was long considered and studied only in solid tumors, it has been shown to be involved in the pathogenesis of hematological malignancies, including acute leukemias. Indeed, there is increasing evidence that EMT promotes the progression of acute leukemias, leading to the emergence of a more aggressive phenotype of the disease, and also causes chemotherapy resistance. The current literature suggests that the levels and activities of EMT inducers and markers can be used to predict prognosis, and that targeting EMT in addition to conventional therapies may increase treatment success in acute leukemias.

Unveiling caspase-2 regulation by non-coding RNAs

Non-coding RNAs (ncRNAs) are a group of RNA molecules, such as small nucleolar RNAs, circular RNAs (circRNAs), microRNAs (miRNAs) and long-noncoding RNAs (ncRNAs), that do not encode proteins. Although their biofunctions are not well-understood, many regulatory ncRNAs appear to be highly involved in regulating the transcription and translation of several genes that have essential biological roles including cell differentiation, cell death, metabolism, tumorigenesis and so on. A growing number of studies have revealed the associations between dysregulated ncRNAs and caspases involved in cell death in numerous human diseases. As one of the initiator and executor caspases, caspase-2 is the most evolutionally conserved caspase in mammals, exerting both apoptotic and non-apoptotic functions. A great deal of studies has shown the involvement of caspase-2 as a tumor suppressor in multiple oncogene-driven cancers, and yet a comprehensive understanding of its biological roles remains largely unknown. In this review, we highlight a compilation of studies focused on the interaction between caspase-2 and miRNAs/lncRNAs in the context of different diseases in order to deepen our knowledge on the regulatory biofunctions of caspase-2 and, furthermore, provide more insight into understanding the role that ncRNAs/caspase-2 axis plays in the development of human diseases.

Tumor-Suppressive and Oncogenic Roles of microRNA-149-5p in Human Cancers

Malignant tumors are always a critical threat to human health, with complex pathogenesis, numerous causative factors, and poor prognosis. The features of cancers, such as gene mutations, epigenetic alterations, and the activation and inhibition of signaling pathways in the organism, play important roles in tumorigenesis and prognosis. MicroRNA (miRNA) enables the control of various molecular mechanisms and plays a variety of roles in human cancers, such as radiation sensitivity and tumor immunity, through the regulation of target genes. MiR-149-5p participates in the process and is closely related to lipogenesis, the migration of vascular endothelial cells, and the expression of stem-cell-related proteins. In recent years, its role in cancer has dramatically increased. In this review, we summarize the regular physiological roles of miRNAs, specifically miR-149-5p, in the organism and discuss the tumor-suppressive or oncogenic roles of miR-149-5p in different human cancers with respect to signaling pathways involved in regulation. Possible clinical applications of miR-149-5p in future targeted therapies and prognosis improvement in oncology are suggested.

MicroRNA-149-3p expression correlates with outcomes of adrenocortical tumor patients and affects proliferation and cell cycle progression of H295A adrenocortical cancer cell line

Pediatric adrenocortical tumor (ACT) is a rare and aggressive neoplasm, with incidence in southern and southeastern Brazil 10-15 times higher than worldwide. Although microRNAs (miRNAs) have been reported to act as tumor suppressors or oncogenes in several cancers, the role of miR-149-3p in ACT remains unknown. In this study, we evaluated the expression of miR-149-3p in 67 pediatric ACT samples and 19 non-neoplastic adrenal tissues. The overexpression of miR-149-3p was induced in H295A cell line, and cell viability, proliferation, colony formation, and cell cycle were assessed by in miR-149-3p mimic or mimic control. In silico analysis were used to predict miR-149-3p putative target genes. CDKN1A expression at the mRNA and protein levels was evaluated by qRT-PCR and western blot, respectively. Higher miR-149-3p expression was associated with unfavorable ACT outcomes. Compared to the mimic control, miR-149-3p overexpression increased cell viability and colony formation, and affected cell cycle progression. Also, we identified CDKN1A as a potential miR-149-3p target gene, with decreased expression at both the gene and protein levels in miR-149-3p mimic cells. Collectively, these findings suggest that miR-149-3p promotes H295A cell viability by downregulating CDKN1A and provide evidence that miR-149-3p may be useful as a novel therapeutic target for pediatric ACT.

MicroRNAs and Efferocytosis: Implications for Diagnosis and Therapy

About 10-100 billion cells are generated in the human body in a day, and accordingly, 10-100 billion cells predominantly die for maintaining homeostasis. Dead cells generated by apoptosis are also rapidly engulfed by macrophages (Mθs) to be degraded. In case of the inefficient engulfment of apoptotic cells (ACs) via Mθs, they experience secondary necrosis and thus release intracellular materials, which display damage-associated molecular patterns (DAMPs) and result in diseases. Over the last decades, researchers have also reflected on the significant contribution of microRNAs (miRNAs) to autoimmune diseases through the regulation of Mθs functions. Moreover, miRNAs have shown intricate involvement with completely adjusting basic Mθs functions, such as phagocytosis, inflammation, efferocytosis, tumor promotion, and tissue repair. In this review, the mechanism of efferocytosis containing "Find-Me", "Eat-Me", and "Digest-Me" signals is summarized and the biogenesis of miRNAs is briefly described. Finally, the role of miRNAs in efferocytosis is discussed. It is concluded that miRNAs represent promising treatments and diagnostic targets in impaired phagocytic clearance, which leads to different diseases.

A Review on the Role of miR-149-5p in the Carcinogenesis

miR-149 is an miRNA with essential roles in carcinogenesis. This miRNA is encoded by the MIR149 gene on 2q37.3. The miR-149 hairpin produces miR-149-5p and miR-149-3p, which are the “guide” and the sister “passenger” strands, respectively. Deep sequencing experiments have shown higher prevalence of miR-149-5p compared with miR-149-3p. Notably, both oncogenic and tumor suppressive roles have been reported for miR-149-5p. In this review, we summarize the impact of miR-149-5p in the tumorigenesis and elaborate mechanisms of its involvement in this process in a variety of neoplastic conditions based on three lines of evidence, i.e., in vitro, in vivo and clinical settings.

Footprints of microRNAs in Cancer Biology

MicroRNAs (miRNAs) are short non-coding RNAs involved in post-transcriptional gene regulation. Over the past years, various studies have demonstrated the role of aberrant miRNA expression in the onset of cancer. The mechanisms by which miRNA exerts its cancer-promoting or inhibitory effects are apparent through the various cancer hallmarks, which include selective proliferative advantage, altered stress response, vascularization, invasion and metastasis, metabolic rewiring, the tumor microenvironment and immune modulation; therefore, this review aims to highlight the association between miRNAs and the various cancer hallmarks by dissecting the mechanisms of miRNA regulation in each hallmark separately. It is hoped that the information presented herein will provide further insights regarding the role of cancer and serve as a guideline to evaluate the potential of microRNAs to be utilized as biomarkers and therapeutic targets on a larger scale in cancer research.

MiR-149-5p: An Important miRNA Regulated by Competing Endogenous RNAs in Diverse Human Cancers

MicroRNAs (miRNAs) consist of a large family of small, non-coding RNAs with the ability to result in gene silencing post-transcriptionally. With recent advances in research technology over the past several years, the physiological and pathological potentials of miRNAs have been gradually uncovered. MiR-149-5p, a conserved miRNA, was found to regulate physiological processes, such as inflammatory response, adipogenesis and cell proliferation. Notably, increasing studies indicate miR-149-5p may act as an important regulator in solid tumors, especially cancers in reproductive system and digestive system. It has been acknowledged that miR-149-5p can function as an oncogene or tumor suppressor in different cancers, which is achieved by controlling a variety of genes expression and adjusting downstream signaling pathway. Moreover, the levels of miR-149-5p are influenced by several newly discovered long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs). However, there is blank about systematic function and mechanism of miR-149-5p in human cancers. In this review, we firstly summarize the present comprehension of miR-149-5p at the molecular level, its vital role in tumor initiation and progression, as well as its potential roles in monitoring diverse reproductive and digestive malignancies.

Mechanism of circADD2 as ceRNA in Childhood Acute Lymphoblastic Leukemia

Background: Acute lymphocytic leukemia (ALL) is the most common malignant tumor in children. Increasing evidence suggests that circular RNAs (circRNAs) play critical regulatory roles in tumor biology. However, the expression patterns and roles of circRNAs in childhood acute lymphoblastic leukemia (ALL) remain largely unknown.

Methods: circADD2 was selected by microarray assay and confirmed by qRT-PCR; in vitro effects of circADD2 were determined by CCK-8 and flow cytometry; while mice subcutaneous tumor model was designed for in vivo analysis. RNA immunoprecipitation and dual-luciferase assay were applied for mechanistic study. Protein levels were examined by Western blot assay.

Results: circADD2 was down-regulated in ALL tissues and cell lines. Overexpression of circADD2 inhibited cell proliferation and promoted apoptosis both in vitro and in vivo. Briefly, circADD2 could directly sponge miR-149-5p, and the level of AKT2, a target gene of miR-149-5p, was downregulated by circADD2.

Conclusion: circADD2, as a tumor suppressor in ALL, can sponge miR-149-5p, and may serve as a potential biomarker for the diagnosis or treatment of ALL.

Hsa-miR-149-5p Suppresses Prostate Carcinoma Malignancy by Suppressing RGS17

Background

MicroRNAs (miRNAs) are key players in the progression of human cancers. While several miRNAs have been reported to regulate the development of tumors, the molecular mechanisms and roles of miR-149-5p in prostate carcinoma (PCa) remain unclear. Our aim was to investigate the interaction and functions of miR-149-5p and RGS17 in PCa.

Methods

Microarray analysis was performed to identify the key miRNA and gene involved in PCa progression. The expression levels of miRNA and mRNA in PCa tissues and cells were verified by qRT-PCR. MTT assay, BrdU proliferation assay and wound-healing assay were applied to assess the effect of miR-149-5p and RGS17 on PCa cells’ viability, proliferation, and migration ability. The association between RGS17 and miR-149-5p was identify using dual-luciferase reporter assay and Western blot assay.

Results

Data analysis indicated the reduction of miR-149-5p expression in PCa tissues and cells. Experimental investigations also showed that this miRNA suppressed the viability, proliferation and migration ability of PCa cells. RGS17 was found to be the target of miR-149-5p, and the low expression of miR-149-5p upregulated RGS17 in PCa tissues and cells. The results of the cell-function assays showed that RGS17 acted as an oncogene in PCa even though its promotive effect could be reversed by miR-149-5p.

Conclusion

This research confirmed that by targeting and inhibiting RGS17, miR-149-5p could suppress PCa development.

Long Non-coding RNA MALAT1 Alleviates the Elevated Intraocular Pressure (Eiop)-induced Glaucoma Progression via Sponging miR-149-5p

Background: Glaucoma is an optic neuropathic disease and contributed to the irreversible blindness caused by the slow death of retinal ganglion cells (RGCs). Long non-coding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) was reported to be aberrantly expressed in diverse diseases, including glaucoma. However, the mechanism of MALAT1 in glaucoma was still undefined.Methods: The levels of MALAT1, microRNA-149-5p (miR-149-5p) in RGCs cultured under elevated pressure were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The putative target of MALAT1 was predicted by starBase v2.0 online database, and dual luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay were performed to verify this interaction. The cell viability of RGCs was measured by Cell Counting Kit-8 (CCK-8) assay. The apoptotic rate was evaluated via flow cytometry. The protein levels of apoptosis-related proteins (Bax, B-cell lymphoma 2 (Bcl-2)) and Cleaved caspase 3 were assessed by Western blot.Results: The level of MALAT1 was significantly down-regulated, and the level of miR-149-5p was distinctly up-regulated in RGCs under pressure in a dose-dependent manner. Functionally, MALAT1 overexpression or miR-149-5p inhibitor alleviated the inhibitory effect on cell viability and the promoted effect on apoptotic rate of RGCs in EIOP. The interaction between MALAT1 and miR-149-5p was predicted by starBase v2.0 online database, and dual luciferase reporter assay, RIP assay and RNA pull-down assay validated the interaction. Combined with the loss and gain experiment results, miR-149-5p was negatively interacted with MALAT1. Furthermore, miR-149-5p mimics mitigated the promoted impact on cell viability and the suppressive impact on apoptotic rate by targeting MALAT1.Conclusion: MALAT1 promoted cell proliferation and inhibited cell apoptosis of RGCs via targeting miR-149-5p in glaucoma in vitro, which might shed light on the mechanism of glaucoma pathogenesis.

lncRNA KCNQ1OT1 promotes the proliferation, migration and invasion of retinoblastoma cells by upregulating HIF-1α via sponging miR-153-3p

It is reported that lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) is oncogenic in many cancers. This work aimed at probing into its expression and biological functions in retinoblastoma (RB) as well as its regulatory effects on miR-153-3p and hypoxia-inducible factor-1α (HIF-1α). In our study, RB samples in pair were collected, and quantitative real-time PCR (qRT-PCR) was employed for examining the expression levels of KCNQ1OT1, miR-153-3p and HIF-1α. KCNQ1OT1 short hairpin RNAs were transfected into SO-Rb50 and HXO-RB44 cell to inhibit the expression of KCNQ1OT1. The proliferative activity, colony formation ability and apoptosis were examined through cell counting kit-8 assay, colony formation assays, Transwell assay and flow cytometry, respectively. qRT-PCR and western blot analysis were used for analyzing the changes of miR-153-3p and HIF-1α induced by KCNQ1OT1. The regulatory relationships between miR-153-3p and KCNQ1OT1, miR-153-3p and HIF-1α were examined by dual luciferase reporter gene assay and RNA-binding protein immunoprecipitation assay. The results of our study showed that KCNQ1OT1 expression was markedly enhanced in RB tissue samples, and KCNQ1OT1 knockdown had an inhibitory effect on the proliferation, migration, invasion and viability of RB cells. There were two validated binding sties between KCNQ1OT1 and miR-153-3p, and KCNQ1OT1 negatively regulated the expression of miR-153-3p in RB cells. HIF-1α was a target gene of miR-153-3p, and could be positively regulated by KCNQ1OT1. In conclusion, our study indicates that KCNQ1OT1 can increase the malignancy of RB cells via regulating miR-153-3p/HIF-1α axis.

Functional Significance of Mirna-149 in Lung Cancer: Can it be Utilized as a Potential Biomarker or a Therapeutic Target?

Accumulating evidence has documented the significance of miR-149 as a promising tumor-suppressive non-coding RNA that play critical roles in regulating genes involved in cancer growth and metastasis. Notably, the ability of miR-149 to be utilized as a potential biomarker in the diagnosis/prognosis or a therapeutic target has also been explored using various cellular and preclinical models, as well as in clinical settings of lung cancer. While the applicability of miR-149 in assessing tumor progression has been suggested, its potential in predicting treatment outcomes is needed to be verified in diverse settings of lung cancer patients. The current review presents an overview of the functional significance of miR-149 with ongoing challenges in non-small cell lung cancer.

B3GNT3, a Direct Target of miR-149-5p, Promotes Lung Cancer Development and Indicates Poor Prognosis of Lung Cancer

Background

B3GNT3 (β1, 3-N-acetylglucosaminyltransferase-3) belongs to the β3GlcNAcT family and is essential to form extended core 1 oligosaccharides. Previous studies revealed that B3GNT3 expression was dysregulated in multiple cancers. Here, we aimed to understand the expression profile and function of B3GNT3 in lung cancer.

Materials and Methods

The expression of B3GNT3 was measured by immunohistochemistry and public database analysis. B3GNT3 was knocked down to evaluate the lung cancer cell proliferation, migration and invasion in in vitro and in vivo tumor formation experiments. miR-149-5p targeting B3GNT3 was identified with TargetScan analysis and confirmed with reporter assay. Overexpression of miR-149-5p was achieved using microRNA mimics and function of microRNA-149-5p/B3GNT3 axis was tested in vitro.

Results

B3GNT3 was upregulated in lung cancer, and B3GNT3 overexpression was associated with poor prognosis of lung cancer patients. High expression of B3GNT3 was associated with advanced TNM stages, larger tumor size, tumor metastasis and recurrence. Functionally, we demonstrated that knockdown of B3GNT3 suppressed lung cancer cell growth and invasion in vitro. Knockdown of B3GNT3 suppressed lung cancer development in a xenograft tumor model. Moreover, miR-149-5p was validated to negatively regulate B3GNT3 expression through directly targeting B3GNT3 3ʹ-UTR. Overexpression of miR-149-5p could antagonize the tumorigenesis effect of B3GNT3 in vitro.

Conclusion

In summary, our study demonstrated that B3GNT3 overexpression was correlated with poor prognosis of lung cancer patient, indicating that B3GNT3 could be a promising prognostic biomarker for lung cancer. miR-149-5p negatively regulated B3GNT3 expression, which might be utilized for therapeutic target in lung cancer.

miR-149-5p mitigates tumor necrosis factor-α-induced chondrocyte apoptosis by inhibiting TRADD

Introduction

Chondrocyte apoptosis as a prominent characteristic is usually accompanied by cartilage degeneration in osteoarthritis (OA). Herein, we aimed to determine the roles of miR-149-5p in tumor necrosis factor-α (TNF-α)-induced chondrocyte apoptosis.

Material and methods

Human chondrocytes were cultured with TNF-α to establish an apoptosis cell model in vitro. After transfection with miR-149-5p mimics or co-expression with TRADD in chondrocytes, cell viability, apoptosis, inflammatory cytokines, mRNA and protein expression were measured using CCK8, Annexin V-FITC double staining, ELISA assays, RT-qPCR and western blotting, respectively.

Results

TNF-α-induced chondrocyte apoptosis occurred in association with the inhibition of cell proliferation, the elevation of inflammatory cytokine levels and the activation of TRADD and caspase-3/8 signaling. The post-transcriptional regulatory mechanism suggested that TRADD was a direct target of miR-149-5p, and overexpression of miR-149-5p resulted in the down-regulation of TRADD protein expression in chondrocytes. In addition, miR-149-5p mimics had the ability to attenuate TNF-α-induced inflammation and apoptosis, while transfection with TRADD vector neutralized the protective effects of miR-149-5p on TNF-α-induced chondrocyte dysfunction.

Conclusions

miR-149-5p inversely regulated TNF-α-mediated chondrocyte damage by inhibiting TRADD-modulated caspases signaling. The miR-149-5p/TRADD signaling pathway might be a promising therapeutic target for the treatment of OA.

miR-362-5p promotes cell proliferation and cell cycle progression by targeting GAS7 in acute myeloid leukemia

Recently, miR-362-5p has attracted special interest as a novel prognostic predictor in acute myeloid leukemia (AML). However, its biological function and underlying molecular mechanism in AML remain to be further defined. Herein, we found that a significant increase in miR-362-5p expression was observed in AML patients and cell lines using quantitative real-time PCR. The expression of miR-362-5p was altered in THP-1 and HL-60 cells by transfecting with miR-362-5p mimic or inhibitor. A series of experiments showed that inhibition of miR-362-5p expression significantly suppressed cell proliferation, induced G0/G1 phase arrest and attenuated tumor growth in vivo. On the contrary, ectopic expression of miR-362-5p resulted in enhanced cell proliferation, cell cycle progression and tumor growth. Moreover, growth arrest-specific 7 (GAS7) was confirmed as a direct target gene of miR-362-5p and was negatively modulated by miR-362-5p. GAS7 overexpression imitated the tumor suppressive effect of silenced miR-362-5p on THP-1 cells. Furthermore, miR-362-5p knockdown or GAS7 overexpression obviously down-regulated the expression levels of PCNA, CDK4 and cyclin D1, but up-regulated p21 expression. Collectively, our findings demonstrate that miR-362-5p exerts oncogenic effects in AML by directly targeting GAS7, which might provide a promising therapeutic target for AML.

miR-149-5p Inhibits Vascular Smooth Muscle Cells Proliferation, Invasion, and Migration by Targeting Histone Deacetylase 4 (HDAC4)

BACKGROUND Studies have demonstrated that microRNAs (miRNAs) have essential roles in biological functions of vascular smooth muscle cells (VSMCs). However, the function and related molecular mechanism of miR-149-5p in VSMCs remains unclear. MATERIAL AND METHODS We used MTT assay, Transwell assay, and wound-healing assay to measure the proliferation, invasion, and migration of VSMCs transfected with miR-149-5p mimics or inhibitors, respectively. Bioinformatics tools and luciferase assay were used to validate the relationship between miR-149-5p and histone deacetylase 4 (HDAC4). Rescue experiments were used to confirm the interaction of miR-149-5p and HDAC4 in regulating biological functions in VSMCs. RESULTS miR-149-5p was downregulated in PDGF-bb-induced VSMCs. It was also found that miR-149-5p overexpression suppressed proliferation, invasion, and migration of VSMCs, while miR-149-5p knockdown showed the opposite effects. Furthermore, HDAC4 was found to be a potential target of miR-149-5p, which rescued miR-149-5p-mediated proliferation, invasion, and migration in VSMCs. CONCLUSIONS We demonstrated that miR-149-5p can suppress biological functions of VSMCs by regulating HDAC4, which might provide a potent therapeutic target for VSMC growth-related diseases.

miR-149-5p protects against high glucose-induced pancreatic beta cell apoptosis via targeting the BH3-only protein BIM

Diabetes mellitus (DM) is characterized by the elevated blood glucose levels and is regarded as one of the most threatening diseases worldwide. The dysfunction of pancreatic beta cells is a key contributor for the pathophysiology of DM. There is growing evidence showing the role of microRNAs (miRNAs) in the regulation of pancreatic beta cell functions. In the present study, we determined the expression of miR-149-5p in pancreatic beta cells under high-glucose (HG) stimulation and explored the underlying mechanism of miR-149-5p-mediated functions of pancreatic beta cells. The results showed the down-regulation of miR-149-5p in the pancreatic beta cell line (MIN6 cells) under HG stimulation. Overexpression of miR-149-5p protected against HG-induced cell apoptosis and impairment of insulin secretion, and attenuated HG-induced an increase in reactive oxygen species (ROS) production in MIN6 cells; while inhibition of miR-149-5p suppressed cell viability, induced cell apoptosis, inhibited insulin secretion and enhanced ROS production in MIN6 cells. Further mechanistic studies revealed that miR-149-5p targeted the BH3-only protein BIM 3' untranslated region and suppressed BIM expression in MIN6 cells. The rescue experimental assays showed that enforced expression of BIM attenuated the miR-149-5p-mediated effects in HG-stimulated pancreatic beta cells. In conclusion, the present study for the first time elucidated the biological functions of miR-149-5p in regulating pancreatic beta cell functions. The data from the present study provided evidence showing that miR-149-5p protected against HG-induced pancreatic beta cell apoptosis partly via suppressing BIM expression. The therapeutic potential of miR-149-5p in the treatment of DM still requires further detailed investigations.

miR-21-5p Suppressed the Sensitivity of Hepatocellular Carcinoma Cells to Cisplatin by Targeting FASLG

Accumulating evidence has suggested that microRNAs play important roles in the development of hepatocellular carcinoma (HCC) and are involved in drug resistance. miR-21-5p was overexpressed in a variety of cancers and promoted the tumorigenesis; however, the function of miR-21-5p in HCC still remains unknown. In this study, our results showed that miR-21-5p was highly expressed in HCC tissues and cell lines. Notably, the level of miR-21-5p was relatively higher in cisplatin (DDP)-resistant HCC patients. Overexpression of miR-21-5p attenuated the inhibitory effect of DDP on the proliferation and apoptosis of HCC cells. Mechanistically, the luciferase report assay-identified FAS ligand (FASLG) was a direct target of miR-21-5p. Overexpression of miR-21-5p decreased both the mRNA and protein levels of FASLG in HCC cells. FASLG was downregulated in HCC tissues and was significantly negatively correlated with the expression of miR-21-5p. Restoring the expression of FASLG upregulated the chemosensitivity of HCC cells expressing miR-21-5p. In conclusion, our results demonstrated that miR-21-5p targeted FASLG and suppressed the sensitivity of HCC cells to DDP treatment.

Role of microRNAs, circRNAs and long noncoding RNAs in acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant tumor of the immature myeloid hematopoietic cells in the bone marrow (BM). It is a highly heterogeneous disease, with rising morbidity and mortality in older patients. Although researches over the past decades have improved our understanding of AML, its pathogenesis has not yet been fully elucidated. Long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs) are three noncoding RNA (ncRNA) molecules that regulate DNA transcription and translation. With the development of RNA-Seq technology, more and more ncRNAs that are closely related to AML leukemogenesis have been discovered. Numerous studies have found that these ncRNAs play an important role in leukemia cell proliferation, differentiation, and apoptosis. Some may potentially be used as prognostic biomarkers. In this systematic review, we briefly described the characteristics and molecular functions of three groups of ncRNAs, including lncRNAs, miRNAs, and circRNAs, and discussed their relationships with AML in detail.

LncRNA-PCAT-1 promotes non-small cell lung cancer progression by regulating miR-149-5p/LRIG2 axis

Long noncoding RNAs (lncRNAs) are key players in the development and progression of human cancers. The lncRNA PCAT-1 has been shown to be upregulated in human non-small cell lung cancer (NSCLC); however, its role and molecular mechanisms in NSCLC cell progression remain unclear. Here, we found that the higher expression of PCAT-1 led to a significantly poorer survival time, and multivariate analysis revealed that PCAT-1 was an independent risk factor of prognosis in NSCLC. Furthermore, we also found that the knockdown of PCAT-1 remarkably suppressed cell growth by inducing cell cycle arrest and apoptosis promotion in NSCLC cells. Moreover, the bioinformatics analysis and luciferase reporter assay revealed that PCAT-1 directly bound to the miR-149-5p, which has been reported to act as a tumor suppressor in diverse cancers. In addition, our results confirmed that the tumor-promoting effects of PCAT-1 in NSCLC cells are at least partly through negative modulation of miR-149-5p. Finally, mechanistic investigations showed that PCAT-1 upregulated the expression of miR-149-5p target gene leucine-rich repeats and immunoglobulin (Ig)-like domains 2 (LRIG2) through competitively "spongeing" miR-149-5p. Therefore, we concluded that PCAT-1 may promote the development of NSCLC through the miR-149-5p/LRIG2 axis.

Mechanisms of drug resistance in acute myeloid leukemia

Acute myeloid leukemia (AML) is a kind of malignant hematopoietic system disease characterized by abnormal proliferation, poor cell differentiation, and infiltration of bone marrow, peripheral blood, or other tissues. To date, the first-line treatment of AML is still based on daunorubicin and cytosine arabinoside or idarubicin and cytosine arabinoside regimen. However, the complete remission rate of AML is still not optimistic, especially in elderly patients, and the recurrence rate after complete remission is still high. The resistance of leukemia cells to chemotherapy drugs becomes the main obstacle in the treatment of AML. At present, the research on the mechanisms of drug resistance in AML is very active. This article will elaborate on the main mechanisms of drug resistance currently being studied, including drug resistance-related proteins and enzymes, gene alterations, micro RNAs, and signal pathways.

Restoration of miRNA-149 Expression by TmPyP4 Induced Unfolding of Quadruplex within Its Precursor

Noncoding RNAs are functional RNA molecules that get transcribed from DNA but are not translated into proteins; yet, they can regulate gene expression at transcriptional and post-transcriptional levels. Secondary structures present within these RNAs play a major role in determining their nature of function. In the case of miRNAs, the precursor miRNA have a hairpin stem loop structure which is required for Dicer recognition and further maturation. Alternately, it might assume a G-quadruplex structure. The transition from hairpin to G-quadruplex depends upon the nucleotide sequence as well as the cellular microenvironment, and this might affect the miRNA maturation and other downstream activity. Formation of the G-quadruplex within precursor miRNA-149 has been shown to inhibit Dicer processing activity followed by suppression of miRNA-149 maturation in cancer cells. In this report, we show that suppression of cell proliferation by the upregulated miRNA-149 could be rescued by unfolding the G-quadruplex present in pre-miRNA-149 by TmPyP4 (Porphyrin) treatment. Using UV-visible spectroscopy, circular dichroism, and isothermal titration calorimetry, we observed that TmPyP4 binds strongly to G-quadruplex and unfolds it, which was further verified by NMR spectroscopy. In cellulo, qRT-PCR measurements of miRNA-149 in MCF-7 breast cancer cells showed concentration dependent enhancement of mature miRNA-149 upon treatment of TmPyP4. As a consequence of enhanced miRNA-149 activity, we also observe the reduction in miRNA-149 target protein ZBTB2 that eventually leads to reduced cell proliferation.

LncRNA PMS2L2 protects ATDC5 chondrocytes against lipopolysaccharide-induced inflammatory injury by sponging miR-203

AIMS

PMS1 Homolog 2, Mismatch Repair System Component Pseudogene 2 (PMS2L2) has been reported as an up-regulated long non-coding RNA (lncRNA) in osteoarthritis (OA) tissues. The purpose of the present work is to explore whether the differently expressed PMS2L2 is associated with the pathogenesis of OA.

MAIN METHODS

Chondrogenic ATDC5 cells were exposed to various doses of lipopolysaccharide (LPS). The expression of PMS2L2, miR-203, and MCL-1 in cell was altered by transfection. Thereafter, cell viability, apoptosis, the expression changes of apoptosis-related factors and the release of pro-inflammatory factors were respectively assessed. Moreover, the regulatory relationship between PMS2L2 and miR-203, as well as between miR-203 and MCL-1 were studied.

KEY FINDINGS

PMS2L2 expression was down-regulated following LPS stimulation. PMS2L2 protected ATDC5 cells against LPS-induced injury by increasing cell viability, decreasing apoptosis, and repressing the release of pro-inflammatory factors. Meanwhile, PMS2L2 increased the expression levels of COL2A1 and ACAN, while down-regulated the expression levels of MMP13 and ADAMTS-5. PMS2L2 worked as a molecular sponge for miR-203. Besides, miR-203 overexpression partially abolished the chondroprotective effects of PMS2L2. MCL-1 was a direct target of miR-203, and it exerted the similarly chondroprotective effects as PMS2L2. Furthermore, PMS2L2 and MCL-1 blocked Wnt/β-Catenin and JAK/STAT signaling pathways also via a miR-203-dependent manner.

SIGNIFICANCE

Our study reveals a protective role of PMS2L2 in LPS-induced inflammatory injury in chondrocytes. PMS2L2/miR-203/MCL-1 axis may serve as a new gene therapy strategy for the treatment of OA.

MicroRNA in leukemia: Tumor suppressors and oncogenes with prognostic potential

Leukemia is known as a progressive malignant disease, which destroys the blood-forming organs and results in adverse effects on the proliferation and development of leukocytes and their precursors in the blood and bone marrow. There are four main classes of leukemia including acute leukemia, chronic leukemia, myelogenous leukemia, and lymphocytic leukemia. Given that a variety of internal and external factors could be associated with the initiation and progression of different types of leukemia. One of the important factors is epigenetic regulators such as microRNAs (miRNAs) and long noncoding RNAs (ncRNA). MiRNAs are short ncRNAs which act as tumor suppressor (i.e., miR-15, miR-16, let-7, and miR-127) or oncogene (i.e., miR-155, miR-17-92, miR-21, miR-125b, miR-93, miR-143-p3, miR-196b, and miR-223) in leukemia. It has been shown that deregulation of these molecules are associated with the initiation and progression of leukemia. Hence, miRNAs could be used as potential therapeutic candidates in the treatment of patients with leukemia. Moreover, increasing evidence revealed that miRNAs could be used as diagnostic and prognostic biomarkers in monitoring patients in early stages of disease or after received chemotherapy regimen. It seems that identification and development of new miRNAs could pave to the way to the development new therapeutic platforms for patients with leukemia. Here, we summarized various miRNAs as tumor suppressor and oncogene which could be introduced as therapeutic targets in treatment of leukemia.

miR-149-5p inhibits cell proliferation and invasion through targeting GIT1 in medullary thyroid carcinoma

Previous studies indicate that miR-149 could both inhibit and promote the development of human cancer depending on the tumor type. GIT1 was found to play an important role in regulating cell migration. However, the specific function of miR-149-5p and GIT1 in the progression of medullary thyroid carcinoma (MTC) remains unknown. The purpose of this study was to confirm the function of miR-149-5p in MTC and explore its downstream regulation. Moreover, miR-149-5p level in MTC was detected via RT-quantitative PCR (RT-qPCR). GIT1 expression levels were assessed by RT-qPCR and western blot analysis. The cell proliferation and invasion were detected through MTT or Transwell assay respectively. In addition, miR-149-5p was identified to directly target GIT1 in MTC via dual luciferase assay. The results suggested that miR-149-5p level was obviously declined in MTC. Functionally, miR-149-5p overexpression inhibited proliferation and invasion. Moreover, miR-149-5p directly targeted GIT1 and was negatively associated with its expression in MTC. Conversely, GIT1 expression was obviously increased in MTC. GIT1 overexpression partially reversed the inhibitory action of miR-149-5p in MTC. miR-149-5p suppressed the proliferation and invasion of MTC cells through targeting GIT1, which would create new therapeutic avenues for MTC treatment.

OncomiR or antioncomiR: Role of miRNAs in Acute Myeloid Leukemia

Acute Myeloid Leukemia (AML) is a hematopoietic progenitor/stem cell disorder in which neoplastic myeloblasts are stopped at an immature stage of differentiation and lost the normal ability of proliferation and apoptosis. MicroRNAs (miRNAs) are small noncoding, single-stranded RNA molecules that can mediate the expression of target genes. While miRNAs mean to contribute the developments of normal functions, abnormal expression of miRNAs and regulations on their corresponding targets have often been found in the developments of AML and described in recent years. In leukemia, miRNAs may function as regulatory molecules, acting as oncogenes or tumor suppressors. Overexpression of miRNAs can down-regulate tumor suppressors or other genes involved in cell differentiation, thereby contributing to AML formation. Similarly, miRNAs can down-regulate different proteins with oncogenic activity as tumor suppressors. We herein review the current data on miRNAs, specifically their targets and their biological function based on apoptosis in the development of AML.

A Novel lncRNA, LINC00460, Affects Cell Proliferation and Apoptosis by Regulating KLF2 and CUL4A Expression in Colorectal Cancer

Emerging evidence has proven that long noncoding RNAs (lncRNAs) play important roles in human colorectal cancer (CRC) biology, although few lncRNAs have been characterized in CRC. Therefore, the functional significance of lncRNAs in the malignant progression of CRC still needs to be further explored. In this study, through analyzing TCGA RNA sequencing data and other publicly available microarray data, we found a novel lncRNA, LINC00460, whose expression was significantly upregulated in CRC tissues compared to adjacent normal tissues. Consistently, real-time qPCR results also verified that LINC00460 was overexpressed in CRC tissues and cells. Furthermore, high LINC00460 expression levels in CRC specimens were correlated with larger tumor size, advanced tumor stage, lymph node metastasis and shorter overall survival. In vitro and in vivo assays of LINC00460 alterations revealed a complex integrated phenotype affecting cell growth and apoptosis. Mechanistically, LINC00460 repressed Krüppel-like factor 2 (KLF2) transcription by binding to enhancer of zeste homolog 2 (EZH2). LINC00460 also functioned as a molecular sponge for miR-149-5p, antagonizing its ability to repress cullin 4A (CUL4A) protein translation. Taken together, our findings support a model in which the LINC00460/EZH2/KLF2 and LINC00460/miR-149-5p/CUL4A crosstalk serve as critical effectors in CRC tumorigenesis and progression, suggesting new therapeutic directions in CRC.

miR-149 in Human Cancer: A Systemic Review

MicroRNAs (miRNAs) are small noncoding RNAs that regulate post-transcriptional gene expression via binding to the 3'-untranslated region (3'-UTR) of targeted mRNAs. They are reported to play important roles in tumorigenesis and progression of various cancers. Among them, miR-149 was confirmed to be aberrantly regulated in various tumors. In this review, we provide a complex overview of miR-149, particularly summarize the critical roles of it in cancers and expect to lay the foundation for future works on this important microRNA.

Expression of miR-149-3p inhibits proliferation, migration, and invasion of bladder cancer by targeting S100A4

MicroRNAs play key roles during various crucial cell processes, such as proliferation, migration, and invasion. In addition, microRNAs have been shown to possess oncogenic and tumor suppressive functions in human cancers. Increasing evidence has clarified that miR-149-3p, a novel cancer-related microRNA, plays an important role in suppression of proliferation, migration, and invasion; however, the effect and mechanisms underlying the miR-149-3p effect in bladder cancer (BCa) remain unclear. In the current study we found that the increased expression of miR-149-3p significantly suppressed cell proliferation, migration, and invasion ability in BCa. The suppressive effect was related to S100A4. A further investigation showed that miR-149-3p negatively regulated S100A4, as verified by the luciferase reporter assay. Furthermore, our study showed that S100A4 mediated the anti-metastatic effects of miR-149-3p on proliferation, migration, and invasion of BCa cells. Analysis of a xenograft mouse model showed that miR-149-3p expression significantly decreased tumor growth by targeting S100A4. Taken together, these data indicate that S100A4 promotes cell growth, migration, and invasion and can by reversed by miR-149-3p in BCa.

microRNAs and Acute Myeloid Leukemia Chemoresistance: A Mechanistic Overview

Up until the early 2000s, a functional role for microRNAs (miRNAs) was yet to be elucidated. With the advent of increasingly high-throughput and precise RNA-sequencing techniques within the last two decades, it has become well established that miRNAs can regulate almost all cellular processes through their ability to post-transcriptionally regulate a majority of protein-coding genes and countless other non-coding genes. In cancer, miRNAs have been demonstrated to play critical roles by modifying or controlling all major hallmarks including cell division, self-renewal, invasion, and DNA damage among others. Before the introduction of anthracyclines and cytarabine in the 1960s, acute myeloid leukemia (AML) was considered a fatal disease. In decades since, prognosis has improved substantially; however, long-term survival with AML remains poor. Resistance to chemotherapy, whether it is present at diagnosis or induced during treatment is a major therapeutic challenge in the treatment of this disease. Certain mechanisms such as DNA damage response and drug targeting, cell cycling, cell death, and drug trafficking pathways have been shown to be further dysregulated in treatment resistant cancers. miRNAs playing key roles in the emergence of these drug resistance phenotypes have recently emerged and replacement or inhibition of these miRNAs may be a viable treatment option. Herein, we describe the roles miRNAs can play in drug resistant AML and we describe miRNA-transcript interactions found within other cancer states which may be present within drug resistant AML. We describe the mechanisms of action of these miRNAs and how they can contribute to a poor overall survival and outcome as well. With the precision of miRNA mimic- or antagomir-based therapies, miRNAs provide an avenue for exquisite targeting in the therapy of drug resistant cancers.

Expression of the miR-148/152 Family in Acute Myeloid Leukemia and its Clinical Significance

Background

MicroRNAs (miRNAs) play an important role in the development and progression of acute myeloid leukemia (AML). The miR-148/152 family has been reported to be express differently in various kinds of tumors. We investigated the expression level of the miR-148/152 family in AML patients and their clinical significance.

Material/Methods

Expression levels of the miR-148/152 family in 80 patients with newly diagnosed AML and 20 healthy participants were analyzed by qRT-PCR. We also evaluated the relationship between the expression levels of the miR-148/152 family and clinicopathological features of AML patients.

Results

Compared with healthy controls, we found a significant lower expression of downregulated miR-148/152 in AML patients (p<0.0001). The expression of miR148/152 family was associated with various AML clinicopathological risk parameters including FAB classifications, cytogenetics, and gene mutations. The number of patients with high expression levels of miR-148a/b was significantly increased in the low-risk group and significantly decreased in the high-risk group. (p=0.025, p=0.000, respectively). Patients with higher expression of miR-148b showed a higher complete remission (CR) rate (p=0.043). Importantly, higher expression of miR-148a/b was correlated with lower relapse rate (p=0.035, p=0.027, respectively) and showed a longer relapse-free survival (RFS) (p=0.0321, p=0.002, respectively). In the subgroup analysis, RFS was significantly affected by the expression of miR-148a/b in patients the high and the intermediate-risk groups (p=0.0499, p=0.0114, respectively).

Conclusions

The expression levels of the miR-148/152 family were lower in patients with AML compared to healthy controls, and were associated with various AML clinicopathological parameters and therapeutic effect. The miR-148/152 family may prove to be a new biomarker for AML.

miR-149 promotes human osteocarcinoma progression via targeting bone morphogenetic protein 9 (BMP9)

OBJECTIVES

To investigate the roles of miR-149 in the progression of human osteosarcoma (OS).

RESULTS

miR-149 level was upregulated in tissues from OS patients more than in normal subjects. Cell proliferation and apoptosis assays revealed that miR-149 increased cell proliferation and inhibited cell apoptosis in OS cell line (MG63). An increase of Bcl-2 gene expression and a decrease of cleaved-caspase-3, and cleaved-PARP expression were observed in MG63 cells with transfection of miR-149. Additionally, bone morphogenetic protein 9 (BMP9) was identified as a target of miR-149 in MG63 cells, and BMP9 expression was negatively correlated with miR149 level in OS clinical samples. Co-overexpression of BMP9 with miR-149 in MG63 cells prohibited miR-149-mediated promotive effects on OS progression. Importantly, overexpression of miR-149 conferred chemoresistance in MG63 cells.

CONCLUSIONS

miR-149 promotes OS progression via targeting BMP9.