Biology of MiR-17-92 Cluster and Its Progress in Lung Cancer

"Crosstalk between non-coding RNAs and transcription factor LRF in non-small cell lung cancer"

Epigenetic approaches in direct correlation with assessment of critical genetic mutations in non-small cell lung cancer (NSCLC) are currently very intensive, as the epigenetic components underlying NSCLC development and progression have attained high recognition. In this level of research, established human NSCLC cell lines as well as experimental animals are widely used to detect novel biomarkers and pharmacological targets to treat NSCLC. The epigenetic background holds a great potential for the identification of epi-biomarkers for treatment response however, it is highly complex and requires precise definition as these phenomena are variable between NSCLC subtypes and systems origin. We engaged an in-depth characterization of non-coding (nc)RNAs prevalent in human KRAS-mutant NSCLC cell lines A549 and H460 and mouse KRAS-mutant NSCLC tissue by Next Generation Sequencing (NGS) and quantitative Real Time PCRs (qPCRs). Also, the transcription factor (TF) LRF, a known epigenetic silencer, was examined as a modulator of non-coding RNAs expression. Finally, interacting networks underlying epigenetic variations in NSCLC subtypes were created. Data derived from our study highlights the divergent epigenetic profiles of NSCLC of human and mouse origin, as well as the significant contribution of 12qf1: 109,709,060-109,747,960 mouse chromosomal region to micro-RNA upregulated species. Furthermore, the novel epigenetic miR-148b-3p/lncPVT1/ZBTB7A axis was identified, which differentiates human cell line of lung adenocarcinoma from large cell lung carcinoma, two characteristic NSCLC subtypes. The detailed recording of epigenetic events in NSCLC and combinational studies including networking between ncRNAs and TFs validate the identification of significant epigenetic features, prevailing in NSCLC subtypes and among experimental models. Our results enrich knowledge in the field and empower research on the epigenetic prognostic biomarkers of the disease progression, NSCLC subtypes discrimination and advancement to patient-tailored treatments.

Exosomal miR-17-92 Cluster from BMSCs Alleviates Apoptosis and Inflammation in Spinal Cord Injury

Spinal cord injury (SCI) involves neuronal apoptosis and axonal disruption, leading to severe motor dysfunction. Studies indicate that exosomes transport microRNAs (miRNAs) and play a crucial role in intercellular communication. This study aimed to explore whether the bone marrow mesenchymal stem cell (BMSCs)-exosomal miR-17-92 cluster can protect against SCI and to explain the underlying mechanisms. In vivo and in vitro SCI models were established and treated with control exosomes (con-exo) or exosomes derived from BMSCs transfected with miR-17-92 cluster plasmid (miR-17-92-exo). Rat BMSCs were isolated and positive markers were identified by flow cytometry. BMSC-derived exosomes were extracted and verified using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blotting. The expression of the miR-17-92 cluster was validated by quantitative reverse transcription PCR (qRT-PCR). Spinal cord function, histopathological changes, apoptotic cells, and inflammatory cytokines release in spinal cord tissues were assessed using the Basso-Beattie-Bresnahan (BBB) score, hematoxylin and eosin (HE) staining, terminal deoxynucleotide transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining, enzyme-linked immunosorbent assay (ELISA), and qRT-PCR. In PC12 cells, cell proliferation, apoptosis, apoptosis-related proteins cleaved-Caspase3 expression, and inflammatory factors secretion were analyzed using a cell counting kit-8 (CCK8) assay, flow cytometry, western blotting, and ELISA. Our data revealed that the exosomes were successfully isolated from rat BMSCs. The BMSC-exosomal miR-17-92 cluster improved neural functional recovery after SCI, as evidenced by an increased BBB score, improved pathological damage, reduced neuronal apoptosis, and decreased inflammatory factors release. Additionally, miR-17-92-exo treatment significantly inhibited lipopolysaccharide (LPS)-induced reduction in cell viability, increase in cell apoptosis, and upregulation of inflammatory factors in PC12 cells. The exosomal miR-17-92 cluster derived from BMSCs improved functional recovery and exhibited neuroprotective effects in SCI by alleviating apoptosis and inflammation.

MEF2C Directly Interacts with Pre-miRNAs and Distinct RNPs to Post-Transcriptionally Regulate miR-23a-miR-27a-miR-24-2 microRNA Cluster Member Expression

Transcriptional regulation constitutes a key step in gene expression regulation. Myocyte enhancer factor 2C (MEF2C) is a transcription factor of the MADS box family involved in the early development of several cell types, including muscle cells. Over the last decade, a novel layer of complexity modulating gene regulation has emerged as non-coding RNAs have been identified, impacting both transcriptional and post-transcriptional regulation. microRNAs represent the most studied and abundantly expressed subtype of small non-coding RNAs, and their functional roles have been widely documented. On the other hand, our knowledge of the transcriptional and post-transcriptional regulatory mechanisms that drive microRNA expression is still incipient. We recently demonstrated that MEF2C is able to transactivate the long, but not short, regulatory element upstream of the miR-23a-miR-27a-miR-24-2 transcriptional start site. However, MEF2C over-expression and silencing, respectively, displayed distinct effects on each of the miR-23a-miR-27a-miR-24-2 mature cluster members without affecting pri-miRNA expression levels, thus supporting additional MEF2C-driven regulatory mechanisms. Within this study, we demonstrated a complex post-transcriptional regulatory mechanism directed by MEF2C in the regulation of miR-23a-miR-27a-miR-24-2 cluster members, distinctly involving different domains of the MEF2C transcription factor and the physical interaction with pre-miRNAs and Ksrp, HnRNPa3 and Ddx17 transcripts.

MicroRNA Monitoring in Human Alveolar Macrophages from Patients with Smoking-Related Lung Diseases: A Preliminary Study

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that is commonly considered to be a potent driver of non-small cell lung cancer (NSCLC) development and related mortality. A growing body of evidence supports a role of the immune system, mainly played by alveolar macrophages (AMs), in key axes regulating the development of COPD or NSCLC phenotypes in response to harmful agents. MicroRNAs (miRNAs) are small non-coding RNAs that influence most biological processes and interfere with several regulatory pathways. The purpose of this study was to assess miRNA expression patterns in patients with COPD, NSCLC, and ever- or never-smoker controls to explore their involvement in smoking-related diseases. Bronchoalveolar lavage (BAL) specimens were collected from a prospective cohort of 43 sex-matched subjects to determine the expressions of hsa-miR-223-5p, 16-5p, 20a-5p, -17-5p, 34a-5p and 106a-5p by RT-PCR. In addition, a bioinformatic analysis of miRNA target genes linked to cancer was performed. Distinct and common miRNA expression levels were identified in each pathological group, suggesting their possible role as an index of NSCLC or COPD microenvironment. Moreover, we identified miRNA targets linked to carcinogenesis using in silico analysis. In conclusion, this study identified miRNA signatures in AMs, allowing us to understand the molecular mechanisms underlying smoking-related conditions and potentially providing new insights for diagnosis or pharmacological treatment.

miR-17-92a-1 cluster host gene: a key regulator in colorectal cancer development and progression

Colorectal cancer (CRC), recognized among the five most prevalent malignancies and most deadly cancers, manifests multifactorial influences stemming from environmental exposures, dietary patterns, age, and genetic predisposition. Although substantial progress has been made in comprehending the etiology of CRC, the precise genetic components driving its pathogenesis remain incompletely elucidated. Within the expansive repertoire of non-coding RNAs, particular focus has centered on the miR-17-92a-1 cluster host gene (MIR17HG) and its associated miRNAs, which actively participate in diverse cellular processes and frequently exhibit heightened expression in various solid tumors, notably CRC. Therefore, the primary objective of this research is to undertake an extensive inquiry into the regulatory mechanisms, structural features, functional attributes, and potential diagnostic and therapeutic implications associated with this cluster in CRC. Furthermore, the intricate interplay between this cluster and the development and progression of CRC will be explored. Our findings underscore the upregulation of the miR-17-92a-1 cluster host gene (MIR17HG) and its associated miRNAs in CRC compared to normal tissues, thus implying their profound involvement in the progression of CRC. Collectively, these molecules are implicated in critical oncogenic processes, encompassing metastatic activity, regulation of apoptotic pathways, cellular proliferation, and drug resistance. Consequently, these findings shed illuminating insights into the potential of MIR17HG and its associated miRNAs as promising targets for therapeutic interventions in the management of CRC.

Multifaceted role of microRNAs in gastric cancer stem cells: Mechanisms and potential biomarkers

MicroRNAs (miRNAs) have received much attention in the past decade as potential key epigenomic regulators of tumors and cancer stem cells (CSCs). The abnormal expression of miRNAs is responsible for different phenotypes of gastric cancer stem cells (GCSCs). Some specific miRNAs could be used as promising biomarkers and therapeutic targets for the identification of GCSCs. This review summarizes the coding process and biological functions of miRNAs and demonstrates their role and efficacy in gastric cancer (GC) metastasis, drug resistance, and apoptosis, especially in the regulatory mechanism of GCSCs. It shows that the overexpression of onco-miRNAs and silencing of tumor-suppressor miRNAs can play a role in promoting or inhibiting tumor metastasis, apart from the initial formation of GC. It also discusses the epigenetic regulation and potential clinical applications of miRNAs as well as the role of CSCs in the pathogenesis of GC. We believe that this review may help in designing novel therapeutic approaches for GC.

Exploring MicroRNA biogenesis, applications and bioinformatics analysis in livestock: A comprehensive review

Small non-coding RNAs called microRNAs (miRNAs) control the expression of genes post-transcriptionally. Their correlation with commercial economic traits including milk, meat and egg production, as well as their effective role in animal productivity, fertility, embryo survival and disease resistance, make them significant in livestock research. The miRNAs exhibit distinct spatial and temporal expression patterns, offering insights into their functional roles within cells and tissues. Aberrant miRNA production can disrupt vital cellular processes and genetic networks, contributing to conditions like metabolic disorders and viral diseases. These short RNA molecules are present in extracellular fluids, displaying remarkable stability against RNA degradation enzymes and extreme environmental conditions. miRNAs preservation is facilitated through packaging in lipid vesicles or complex formation with RNA-binding proteins. Numerous studies have illuminated the roles of miRNAs in diverse physiological processes, including embryonic stem cell differentiation, haematopoietic stem cell proliferation and differentiation and the coordinated development of organ systems. The integration of miRNA profiling, next-generation sequencing and bioinformatics analysis paves the way for transformative advancements in livestock research and industry. The present review underscores the applications of miRNAs in livestock, showcasing their potential to improve breeding strategies, diagnose diseases and enhance our understanding of fundamental biological processes.

The Role of microRNAs in Hepatocellular Cancer: A Narrative Review Focused on Tumor Microenvironment and Drug Resistance

Globally, hepatic cancer ranks fourth in terms of cancer-related mortality and is the sixth most frequent kind of cancer. Around 80% of liver cancers are hepatocellular carcinomas (HCC), which are the leading cause of cancer death. It is well known that HCC may develop resistance to the available chemotherapy treatments very fast. One of the biggest obstacles in providing cancer patients with appropriate care is drug resistance. According to reports, more than 90% of cancer-specific fatalities are caused by treatment resistance. By binding to the 3'-untranslated region of target messenger RNAs (mRNAs), microRNAs (miRNAs), a group of noncoding RNAs which are around 17 to 25 nucleotides long, regulate target gene expression. Moreover, they play role in the control of signaling pathways, cell proliferation, and cell death. As a result, miRNAs play an important role in the microenvironment of HCC by changing immune phenotypes, hypoxic conditions, and acidification, as well as angiogenesis and extracellular matrix components. Moreover, changes in miRNA levels in HCC can effectively resist cancer cells to chemotherapy by affecting various cellular processes such as autophagy, apoptosis, and membrane transporter activity. In the current work, we narratively reviewed the role of miRNAs in HCC, with a special focus on tumor microenvironment and drug resistance.

Recent advances on high-efficiency of microRNAs in different types of lung cancer: a comprehensive review

Carcinoma of the lung is among the most common types of cancer globally. Concerning its histology, it is categorized as a non-small cell carcinoma (NSCLC) and a small cell cancer (SCLC) subtype. MicroRNAs (miRNAs) are a member of non-coding RNA whose nucleotides range from 19 to 25. They are known to be critical regulators of cancer via epigenetic control of oncogenes expression and by regulating tumor suppressor genes. miRNAs have an essential function in a tumorous microenvironment via modulating cancer cell growth, metastasis, angiogenesis, metabolism, and apoptosis. Moreover, a wide range of information produced via several investigations indicates their tumor-suppressing, oncogenic, diagnostic assessment, and predictive marker functions in different types of lung malignancy. miRNA mimics or anti-miRNAs can be transferred into a lung cancer cell, with possible curative implications. As a result, miRNAs hold promise as targets for lung cancer treatment and detection. In this study, we investigate the different functions of various miRNAs in different types of lung malignancy, which have been achieved in recent years that show the lung cancer-associated regulation of miRNAs expression, concerning their function in lung cancer beginning, development, and resistance to chemotherapy, also the probability to utilize miRNAs as predictive biomarkers for therapy reaction.

miR-92a-3p regulates cisplatin-induced cancer cell death

Non-small cell lung cancer is characterized by a dismal prognosis largely owing to inefficient diagnosis and tenacious drug resistance. Therefore, the identification of new molecular determinants underlying sensitivity of cancer cells to existing therapy is of particular importance to develop new effective combinatorial treatment strategy. MicroRNAs (miRNAs), a class of small non-coding RNAs, have been established as master regulators of a variety of cellular processes that play a key role in tumor initiation, progression and metastasis. This, along with their widespread deregulation in many distinct cancers, has triggered enthusiasm for miRNAs as novel therapeutic targets for cancer management, in particular in patients with refractory cancers such as those harboring KRAS mutations. In this study, we performed a loss-of-function screening approach to identify miRNAs whose silencing promotes sensitivity of lung adenocarcinoma (LUAD) cells to cisplatin. Our results showed in particular that antisense oligonucleotides directed against miR-92a-3p, a member of the oncogenic miR-17 ~ 92 cluster, caused the greatest increase in the sensitivity of KRAS-mutated LUAD cells to cisplatin. In addition, we demonstrated that this miRNA finely regulates the apoptotic threshold and the proliferative capacity of various tumor cell lines with distinct genetic alterations. Collectively, these data suggest that targeting miR-92a-3p may serve as an effective strategy to overcome treatment resistance of solid tumors.

In vitro analysis of PI3K pathway activation genes for exploring novel biomarkers and therapeutic targets in clear cell renal carcinoma

OBJECTIVES

The regulation of various cellular functions such as growth, proliferation, metabolism, and angiogenesis, is dependent on the PI3K pathway. Recent evidence has indicated that kidney renal clear cell carcinoma (KIRC) can be triggered by the deregulation of this pathway. The objective of this research was to investigate 25 genes associated with activation of the PI3K pathway in KIRC and control samples to identify four hub genes that might serve as novel molecular biomarkers and therapeutic targets for treating KIRC.

METHODS

Multi-omics in silico and in vitro analysis was employed to find hub genes related to the PI3K pathway that may be biomarkers and therapeutic targets for KIRC.

RESULTS

Using STRING software, a protein-protein interaction (PPI) network of 25 PI3K pathway-related genes was developed. Based on the degree scoring method, the top four hub genes were identified using Cytoscape's Cytohubba plug-in. TCGA datasets, KIRC (786-O and A-498), and normal (HK2) cells were used to validate the expression of hub genes. Additionally, further bioinformatic analyses were performed to investigate the mechanisms by which hub genes are involved in the development of KIRC. Out of a total of 25 PI3K pathway-related genes, we developed and validated a diagnostic and prognostic model based on the up-regulation of TP53 (tumor protein 53) and CCND1 (Cyclin D1) and the down-regulation of PTEN (Phosphatase and TENsin homolog deleted on chromosome 10), and GSK3B (Glycogen synthase kinase-3 beta) hub genes. The hub genes included in our model may be a novel therapeutic target for KIRC treatment. Additionally, associations between hub genes and infiltration of immune cells can enhance comprehension of immunotherapy for KIRC.

CONCLUSION

We have created a new diagnostic and prognostic model for KIRC patients that uses PI3K pathway-related hub genes (TP53, PTEN, CCND1, and GSK3B). Nevertheless, further experimental studies are required to ascertain the efficacy of our model.

MYC regulates CSF1 expression via microRNA 17/20a to modulate tumor-associated macrophages in osteosarcoma

Osteosarcoma (OS) is the most common primary bone tumor of childhood. Approximately 20%-30% of OSs carry amplification of chromosome 8q24, which harbors the oncogene c-MYC and correlates with a poor prognosis. To understand the mechanisms that underlie the ability of MYC to alter both the tumor and its surrounding tumor microenvironment (TME), we generated and molecularly characterized an osteoblast-specific Cre-Lox-Stop-Lox-c-MycT58A p53fl/+ knockin genetically engineered mouse model (GEMM). Phenotypically, the Myc-knockin GEMM had rapid tumor development with a high incidence of metastasis. MYC-dependent gene signatures in our murine model demonstrated significant homology to the human hyperactivated MYC OS. We established that hyperactivation of MYC led to an immune-depleted TME in OS demonstrated by the reduced number of leukocytes, particularly macrophages. MYC hyperactivation led to the downregulation of macrophage colony-stimulating factor 1, through increased microRNA 17/20a expression, causing a reduction of macrophage population in the TME of OS. Furthermore, we developed cell lines from the GEMM tumors, including a degradation tag-MYC model system, which validated our MYC-dependent findings both in vitro and in vivo. Our studies utilized innovative and clinically relevant models to identify a potentially novel molecular mechanism through which MYC regulates the profile and function of the OS immune landscape.

High expression of miR-107 and miR-17 predicts poor prognosis and guides treatment selection in acute myeloid leukemia

Background

The prognostic significance of miR-107 and miR-17 in patients with acute myeloid leukemia (AML) remains unclear.

Methods

A total of 173 patients with de novo AML from the Cancer Genome Atlas database were enrolled in this study and further divided into a chemotherapy group (98 cases) and an allogeneic hematopoietic stem cell transplantation (allo-HSCT) group (75 cases) according to their therapy regimen.

Results

In the chemotherapy cohort, high miR-107 or miR-17 expression was associated with poorer overall survival (OS) and event-free survival (EFS). On the other hand, there were no significant differences in OS and EFS between the high- and low-expression subgroups in the allo-HSCT group. Next, we stratified the total number of patients with AML into high- and low-expression groups according to the median expression levels of miR-107 or miR-17. In the high miR-107 or miR-17 expression group, patients treated with allo-HSCT had longer OS than those treated with chemotherapy. In the low miR-107 or miR-17 expression group, no significant differences in OS and EFS were observed between the two therapy subgroups. When patients were further clustered into three groups (both low miR-107 and low miR-17, either high miR-107 or high miR-17, and both high miR-107 and high miR-17), patients with both high miR-107 and high miR-17 expression had the worst OS and EFS of the entire group and of the chemotherapy group. On the other hand, there were no significant differences in OS and EFS among the three subgroups in the allo-HSCT group. Cox regression confirmed the concurrence of high expression of miR-107 and miR-17 might act as an independent prognostic factor for EFS and OS in the entire group and the chemotherapy group. Bioinformatics analysis showed differentially expressed genes (DEGs) associated with miR-107 and miR-17 expression were mainly enriched in multiple metabolic processes.

Conclusions

The combination of miR-107 and miR-17 provides prognostic significance for patients with AML and should be considered in the clinical selection of the optimal treatment regimen when deciding between chemotherapy and allo-HSCT.

MicroRNA-17-3p protects against excessive posthypoxic autophagy in H9C2 cardiomyocytes via PTEN-Akt-mTOR signaling pathway

The activity of phosphatase and tensin homolog (PTEN) can be inhibited by miR-17-3p, which results in attenuating myocardial ischemia/reperfusion injury (IRI), however, the mechanism behind this phenomenon is still elusive. Suppression of PTEN leads to augmented protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling strength and constrained autophagy activation, which might be the one mechanism for the ameliorated myocardial IRI. Thus, we tested the hypothesis that miR-17-3p attenuated hypoxia/reoxygenation (H/R)-mediated damage in cardiomyocytes by downregulating excessive autophagy via the PTEN-Akt-mTOR axis. The expression of miR-17-3p was remarkably increased after H/R treatment (6-h hypoxia followed by 6-h reoxygenation; H6/R6), which was concomitant with the increase of the release of lactic acid dehydrogenase (cell injury marker) and the enhancement LC3II/I ratio (autophagy markers) in H9C2 cardiomyocytes. Ectoexpression of miR-17-3p agomir led to remarkable augmentation of miR-17-3p expression and evidently attenuated H/R-mediated cell damage and excessive autophagy. Furthermore, an increase in miR-17-3p expression elicited constrained phosphorylation of PTEN (Ser³⁸⁰ ) while enhanced the phosphorylation of Akt (Thr³⁰⁸ , Ser⁴⁷³ ) and mTOR (Ser⁵³⁶ ) after H/R stimulation. In addition, pretreatment with LY-294002 (an Akt selective inhibitor) and rapamycin (an mTOR selective inhibitor) significantly abrogated the protective function of miR-17-3p on H/R-mediated cell damage and autophagy in H9C2 cardiomyocytes. Taken together, these observations indicated that the enhancement of the PTEN/Akt/mTOR axis and the consequent suppression of autophagy overactivation might represent an underlying mechanism by which miR-17-3p attenuated H/R-mediated damage in H9C2 cells.

Differentially deregulated microRNAs contribute to ultraviolet radiation-induced photocarcinogenesis through immunomodulation: An-analysis of microRNAs expression profiling

MicroRNAs (miRNAs) are short non-coding RNA molecules (18-25 nucleotides) that regulate several fundamental biological processes. Emerging evidence has shown more than 1500 miRNAs functions in the cell cycle, proliferation, apoptosis, oxidative stress, immune response, DNA damage, and epigenetics alterations. miRNAs are bidirectionally in nature and act as a tumor suppressor and as an oncogene through crosstalk between tumor cells and immune cells. Although the roles of miRNAs in several cancers are well studied, little is known about ultraviolet B (UVB) radiation-induced skin cancer. Here, we performed a comprehensive screening of 1281 miRNAs in tumor tissues and compared their expression with normal skin. Our results demonstrate that the expression levels of 587 miRNAs were altered in tumor tissues compared to their expression in normal skin. The expression of 337 miRNAs was upregulated from 1.5-12 folds, while the expression of 250 miRNAs was downregulated up to 1.5-10 folds in tumors. Further, intraperitoneal injection of a mimic of down-regulated miR-15b (30nM) and an inhibitor of upregulated miR-133a (20nM) protect UVB-induced suppression of contact hypersensitivity (CHS) response. In conclusion, we identified a network of altered miRNAs in tumors that can serve as prognostic biomarkers and therapeutic targets to manage photocarcinogenesis effectively.

Aberrant Methylation of the Imprinted C19MC and MIR371-3 Clusters in Patients with Non-Small Cell Lung Cancer

Epigenetic mechanisms have emerged as an important contributor to tumor development through the modulation of gene expression. Our objective was to identify the methylation profile of the imprinted C19MC and MIR371-3 clusters in patients with non-small cell lung cancer (NSCLC) and to find their potential target genes, as well as to study their prognostic role. DNA methylation status was analyzed in a NSCLC patient cohort (n = 47) and compared with a control cohort including COPD patients and non-COPD subjects (n = 23) using the Illumina Infinium Human Methylation 450 BeadChip. Hypomethylation of miRNAs located on chromosome 19q13.42 was found to be specific for tumor tissue. We then identified the target mRNA-miRNA regulatory network for the components of the C19MC and MIR371-3 clusters using the miRTargetLink 2.0 Human tool. The correlations of miRNA-target mRNA expression from primary lung tumors were analyzed using the CancerMIRNome tool. From those negative correlations identified, we found that a lower expression of 5 of the target genes (FOXF2, KLF13, MICA, TCEAL1 and TGFBR2) was significantly associated with poor overall survival. Taken together, this study demonstrates that the imprinted C19MC and MIR371-3 miRNA clusters undergo polycistronic epigenetic regulation leading to deregulation of important and common target genes with potential prognostic value in lung cancer.

Emerging role of non-coding RNAs in resistance to platinum-based anti-cancer agents in lung cancer

Platinum-based drugs are the first line of therapeutics against many cancers, including lung cancer. Lung cancer is one of the leading causes of cancer-related death worldwide. Platinum-based agents target DNA and prevent replication, and transcription, leading to the inhibition of cell proliferation followed by cellular apoptosis. About twenty-three platinum-based drugs are under different stages of clinical trials, among cisplatin, carboplatin, and oxaliplatin are widely used for the treatment of various cancers. Among them, cisplatin is the most commonly used drug for cancer therapy, which binds with RNA, and hinders the cellular RNA process. However, long-term use of platinum-based drugs can cause different side effects and has been shown to develop chemoresistance, leading to poor clinical outcomes. Chemoresistance became an important challenge for cancer treatment. Platinum-based chemoresistance occurs due to the influence of intrinsic factors such as overexpression of multidrug resistance proteins, advancement of DNA repair mechanism, degradation, and deactivation of intracellular thiols. Recently, epigenetic modifications, especially non-coding RNAs (ncRNAs) mediated gene regulation, grasp the attention for reversing the sensitivity of platinum-based drugs due to their reversible nature without altering genome sequence. ncRNAs can also modulate the intrinsic and non-intrinsic mechanisms of resistance in lung cancer cells. Therefore, targeting ncRNAs could be an effective approach for developing novel therapeutics to overcome lung cancer chemoresistance. The current review article has discussed the role of ncRNA in chemoresistance and its underlying molecular mechanisms in human lung cancer.

LINC00511 promotes cervical cancer progression by regulating the miR-497-5p/MAPK1 axis

BACKGROUND

Long non-coding RNA (lncRNA) exhibits a crucial role in multiple human malignancies. The expression of lncRNA LINC00511, reportedly, is aberrantly up-regulated in several types of tumors. Our research was aimed at deciphering the role and mechanism of LINC00511 in the progression of cervical cancer (CC).

METHOD

Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to quantify the expression levels of LINC00511, miR-497-5p and MAPK1 mRNA in CC tissues and cell lines. Cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU) and Transwell assays were conducted for detecting the proliferation, migration and invasion of CC cells. Dual-luciferase reporter gene experiments were performed to verify the targeting relationships amongst LINC00511, miR-497-5p and MAPK1. Besides, MAPK1 expression in CC cells was detected via Western blot after LINC00511 and miR-497-5p were selectively regulated.

RESULTS

Up-regulation of LINC00511 expression in CC tissues and cell lines was observed, which was in association with tumor size, clinical stage and lymph node metastasis of the patients. LINC00511 overexpression facilitated the proliferation, migration and invasion of CC cells, while opposite effects were observed after knockdown of LINC00511. Mechanistically, LINC00511 was capable of targeting miR-497-5p and up-regulating MAPK1 expression.

CONCLUSION

LINC00511/miR-497-5p/MAPK1 axis regulates CC progression.

MicroRNA-92a-3p-mediated inhibition of BCL11A upregulates γ-globin expression and inhibits oxidative stress and apoptosis in erythroid precursor cells

OBJECTIVE

This study attempted to investigate miR-92a-3p expression in peripheral blood of patients with severe β-thalassemia, and the effect and action mechanism of miR-92a-3p on γ-globin expression and oxidative stress in erythroid precursor cells.

METHODS

CD34⁺ hematopoietic progenitor cells (HPCs) were isolated from peripheral blood of healthy volunteers and patients with severe β-thalassemia. The levels of miR-92a-3p, BCL11A, and γ-globin were measured in erythroid precursor cells. High-performance liquid chromatography (HPLC) was used to analyze hemoglobin F (HbF) content. HPCs were induced with erythroid differentiation and erythroid precursor cells were then obtained. The relevance between miR-92a-3p and BCL11A was studied using dual luciferase reporter gene assay, and the correlation between miR-92a-3p and HbF was assayed by Pearson correlation analysis. Reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) in erythroid precursor cells were tested to evaluate oxidative stress. Cell apoptosis was examined by flow cytometry.

RESULTS

Remarkably higher expression of miR-92a-3p was observed in erythroid precursor cells. Increased expression of miR-92a-3p resulted in elevated levels of γ-globin, GSH, and SOD, reduced expression of ROS and MDA, and decreased cell apoptosis. BCL11A was identified as a target of miR-92a-3p and to be downregulated by miR-92a-3p. Moreover, BCL11A knockdown alone increased the expression of γ-globin, SOD and GSH, and repressed the levels of ROS and MDA and cell apoptosis, and the following inhibition of miR-92a-3p changed these patterns.

CONCLUSIONS

Our data indicated that miR-92a-3p might increase γ-globin level and reduce oxidative stress and apoptosis in erythroid precursor cells by downregulating BCL11A.

The Underestimated Role of the p53 Pathway in Renal Cancer

The TP53 tumor suppressor gene is known as the guardian of the genome, playing a pivotal role in controlling genome integrity, and its functions are lost in more than 50% of human tumors due to somatic mutations. This percentage rises to 90% if mutations and alterations in the genes that code for regulators of p53 stability and activity are taken into account. Renal cell carcinoma (RCC) is a clear example of cancer that despite having a wild-type p53 shows poor prognosis because of the high rate of resistance to radiotherapy or chemotherapy, which leads to recurrence, metastasis and death. Remarkably, the fact that p53 is poorly mutated does not mean that it is functionally active, and increasing experimental evidences have demonstrated this. Therefore, RCC represents an extraordinary example of the importance of p53 pathway alterations in therapy resistance. The search for novel molecular biomarkers involved in the pathways that regulate altered p53 in RCC is mandatory for improving early diagnosis, evaluating the prognosis and developing novel potential therapeutic targets for better RCC treatment.

MicroRNAs as immune regulators and biomarkers in tuberculosis

Tuberculosis (TB), which is caused by Mycobacterium tuberculosis (Mtb), is one of the most lethal infectious disease worldwide, and it greatly affects human health. Some diagnostic and therapeutic methods are available to effectively prevent and treat TB; however, only a few systematic studies have described the roles of microRNAs (miRNAs) in TB. Combining multiple clinical datasets and previous studies on Mtb and miRNAs, we state that pathogens can exploit interactions between miRNAs and other biomolecules to avoid host mechanisms of immune-mediated clearance and survive in host cells for a long time. During the interaction between Mtb and host cells, miRNA expression levels are altered, resulting in the changes in the miRNA-mediated regulation of host cell metabolism, inflammatory responses, apoptosis, and autophagy. In addition, differential miRNA expression can be used to distinguish healthy individuals, patients with TB, and patients with latent TB. This review summarizes the roles of miRNAs in immune regulation and their application as biomarkers in TB. These findings could provide new opportunities for the diagnosis and treatment of TB.

Expression of miR-92a is associated with the prognosis in non-small cell lung cancer: An observation study

With the development of molecular biology technology, the discovery of microRNAs (miRNAs) has provided new ideas for the diagnosis, treatment, and prognosis of lung cancer and laid a foundation for the study of this malignancy. To assess the potential prognostic value of miR-92a as a new biomarker in non-small cell lung cancer (NSCLC) via clinical evaluation, a total of 100 patients with NSCLC admitted to the Respiratory and Intensive Care Department of Suining Central Hospital in Sichuan Province between August 2007 and April 2020 were retrospectively analyzed. The correlation between miR-92a expression and prognosis of patients with NSCLC was also evaluated in the present study. The expression level of miR-92a was measured by PT-PCR and in situ hybridization. Chi-square test was adopted to explore the relationship of miR-92a expression and clinical features. Kaplan-Meier survival curves were plotted to delineate the overall survival rate of patients with NSCLC. Cox regression analysis was performed to evaluate the prognostic significance of miR-92a expression in NSCLC. The miR-92a expression in NSCLC tissue samples was significantly higher than that in normal lung tissues (P < .001) and significantly correlated with the Eastern Cooperative Oncology Group score, histological type, and distant metastasis (P < .05). Survival curve revealed that patients with NSCLC and high miR-92a expression had relatively higher mortality than those with low PAK4 expression (P = .001). Cox regression analysis explained that miR-92a expression was associated with the prognosis of patients with NSCLC (HR = 1.8, 95% CI: 1.0-3.2, P = .036). In summary, miR-92a was highly expressed in NSCLC tissues and could act as a prognostic factor for patients with NSCLC. These results illustrate that miR-92a expression plays an important role in the invasion and metastasis of NSCLC, and miR-92a can be used as a new biomarker to determine the prognosis of this cancer.

Role of epigallocatechin-3- gallate in the regulation of known and novel microRNAs in breast carcinoma cells

Breast cancer comprises 30% of all cancer cases among the world’s women population. MicroRNAs are small, endogenous, non-coding RNAs that regulate cell proliferating and apoptotic pathways by modulating expressions of related genes. Phytochemicals like epigallocatechin-3-gallate (EGCG) are known to have a chemotherapeutic effect on cancer often through the regulation of microRNAs. The aim is to find out the key known and novel miRNAs, which are controlled by EGCG in breast cancer cell line MDA-MB-231. Next-generation sequencing (NGS) revealed 1,258 known and 330 novel miRNAs from untreated and 83 μM EGCG (IC50 value of EGCG) treated cells. EGCG modulated 873 known and 47 novel miRNAs in the control vs. treated sample. The hypothesis of EGCG being a great modulator of miRNAs that significantly control important cancer-causing pathways has been established by analyzing with Kyoto Encyclopedia of Genes and Genomes (KEGG) and Protein Analysis Through Evolutionary Relationships (PANTHER) database. Validation of known and novel miRNA expression differences in untreated vs. treated cells was done using qPCR. From this study, a few notable miRNAs were distinguished that can be used as diagnostics as well as prognostic markers for breast cancer.

OncomiRs as noncoding RNAs having functions in cancer: Their role in immune suppression and clinical implications

Currently, microRNAs have been established as central players in tumorigenesis, but above all, they have opened an important door for our understanding of immune and tumor cell communication. This dialog is largely due to onco-miR transfer from tumor cells to cells of the tumor microenvironment by exosome. This review outlines recent advances regarding the role of oncomiRs in enhancing cancer and how they modulate the cancer-related immune response in the tumor immune microenvironment.

MicroRNAs (miRNAs) are a type of noncoding RNA that are important posttranscriptional regulators of messenger RNA (mRNA) translation into proteins. By regulating gene expression, miRNAs enhance or inhibit cancer development and participate in several cancer biological processes, including proliferation, invasion metastasis, angiogenesis, chemoresistance and immune escape. Consistent with their widespread effects, miRNAs have been categorized as oncogenes (oncomiRs) or tumor suppressor (TS) miRNAs. MiRNAs that promote tumor growth, called oncomiRs, inhibit messenger RNAs of TS genes and are therefore overexpressed in cancer. In contrast, TS miRNAs inhibit oncogene messenger RNAs and are therefore underexpressed in cancer. Endogenous miRNAs regulate different cellular pathways in all cell types. Therefore, they are not only key modulators in cancer cells but also in the cells constituting their microenvironments. Recently, it was shown that miRNAs are also involved in intercellular communication. Indeed, miRNAs can be transferred from one cell type to another where they regulate targeted gene expression. The primary carriers for the transfer of miRNAs from one cell to another are exosomes. Exosomes are currently considered the primary carriers for communication between the tumor and its surrounding stromal cells to support cancer progression and drive immune suppression. Exosome and miRNAs are seen by many as a hope for developing a new class of targeted therapy. This review outlines recent advances in understanding the role of oncomiRs in enhancing cancer and how they promote its aggressive characteristics and deeply discusses the role of oncomiRs in suppressing the anticancer immune response in its microenvironment. Additionally, further understanding the mechanism of oncomiR-related immune suppression will facilitate the use of miRNAs as biomarkers for impaired antitumor immune function, making them ideal immunotherapy targets.

miRNA in Molecular Diagnostics

MicroRNAs are a class of small non-coding RNA molecules that regulate gene expression on post-transcriptional level. Their biogenesis consists of a complex series of sequential processes, and they regulate expression of many genes involved in all cellular processes. Their function is essential for maintaining the homeostasis of a single cell; therefore, their aberrant expression contributes to development and progression of many diseases, especially malignant tumors and viral infections. Moreover, they can be associated with certain states of a specific disease, obtained in the least invasive manner for patients and analyzed with basic molecular methods used in clinical laboratories. Because of this, they have a promising potential to become very useful biomarkers and potential tools in personalized medicine approaches. In this review, miRNAs biogenesis, significance in cancer and infectious diseases, and current available test and methods for their detection are summarized.

The diagnostic and prognostic value of the miR-17-92 cluster in hepatocellular carcinoma: A meta-analysis

Previous studies demonstrated that microRNAs (miRNAs) could serve as biomarkers in various cancers. This meta-analysis aimed to determine the roles of a miR-17-92 cluster in hepatocellular carcinoma (HCC). Here, eligible included studies were searched through PubMed, Embase, and Wan Fang databases up to 1st February 2022. Relevant data were extracted from each eligible study to evaluate the relationship between miRNA-17-92 cluster miRNA expression and the diagnosis and prognosis of HCC. Finally, a total of 21 studies were pooled and included in the meta-analysis, of which four articles were used for diagnostic meta-analysis and eight articles were used for prognostic meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratios (DOR) of the miR17-92 cluster for diagnosis of HCC were 0.75 [95% confidence interval (CI): 0.64–0.83], 0.73 (95% CI: 0.65–0.79), and 7.87 (95% CI: 5.36–11.54), respectively. Also, the area under the curve (AUC) for the miR-17-92 cluster when diagnosing HCC was 0.79 (95% CI: 0.76–0.83). For prognostic analysis, hazard ratios (HRs) with 95% CIs were extracted from the included studies and pooled HRs were determined to assess the associations. Patients with increased expression of miR17-92 cluster miRNA were associated with poor overall survival (OS) and recurrence-free survival (RFS) (HR=1.86, 95% CI: 1.04–3.33; HR = 4.18, 95% CI: 3.02–5.77, respectively), but not progression-free survival (PFS) (HR = 0.43, 95% CI: 0.25–0.73), while no association of the miR-17-92 cluster high-expression was detected with disease-free survival (DFS) (HR: 0.95, 95% CI: 0.21–4.34). In short, current pieces of evidence suggested that the miR-17-92 cluster may serve as a novel diagnostic and prognostic biomarker for HCC. However, given the limited study number, larger-size, multi-center, and higher-quality studies are indispensable in the future.

Recent insights into the microRNA-dependent modulation of gliomas from pathogenesis to diagnosis and treatment

Gliomas are the most lethal primary brain tumors in adults. These highly invasive tumors have poor 5-year survival for patients. Gliomas are principally characterized by rapid diffusion as well as high levels of cellular heterogeneity. However, to date, the exact pathogenic mechanisms, contributing to gliomas remain ambiguous. MicroRNAs (miRNAs), as small noncoding RNAs of about 20 nucleotides in length, are known as chief modulators of different biological processes at both transcriptional and posttranscriptional levels. More recently, it has been revealed that these noncoding RNA molecules have essential roles in tumorigenesis and progression of multiple cancers, including gliomas. Interestingly, miRNAs are able to modulate diverse cancer-related processes such as cell proliferation and apoptosis, invasion and migration, differentiation and stemness, angiogenesis, and drug resistance; thus, impaired miRNAs may result in deterioration of gliomas. Additionally, miRNAs can be secreted into cerebrospinal fluid (CSF), as well as the bloodstream, and transported between normal and tumor cells freely or by exosomes, converting them into potential diagnostic and/or prognostic biomarkers for gliomas. They would also be great therapeutic agents, especially if they could cross the blood–brain barrier (BBB). Accordingly, in the current review, the contribution of miRNAs to glioma pathogenesis is first discussed, then their glioma-related diagnostic/prognostic and therapeutic potential is highlighted briefly.

Tumor-targeted miRNA nanomedicine for overcoming challenges in immunity and therapeutic resistance

miRNA are critical messengers in the tumor microenvironment (TME) that influence various processes leading to immune suppression, tumor progression, metastasis and resistance. Strategies to modulate miRNAs in the TME have important implications in overcoming these challenges. However, miR delivery to specific cells in the TME has been challenging. This review discusses nanomedicine strategies to achieve cell-specific delivery of miRNAs. The key goal of delivery is to activate the tumor immune landscape as well as to prevent chemotherapy resistance. Specifically, the use of hyaluronic acid-based nanoparticle miRNA delivery to the TME is discussed. The discussion is focused on miRNA-125b for reprogramming tumor-associated macrophages to overcome immunosuppression and miRNA-let-7b to overcome resistance to anticancer chemotherapeutics because both these miRNAs have been extensively evaluated for delivery with hyaluronic acid-based delivery systems.

Computational method using heterogeneous graph convolutional network model combined with reinforcement layer for MiRNA-disease association prediction

BACKGROUND

A large number of evidences from biological experiments have confirmed that miRNAs play an important role in the progression and development of various human complex diseases. However, the traditional experiment methods are expensive and time-consuming. Therefore, it is a challenging task that how to develop more accurate and efficient methods for predicting potential associations between miRNA and disease.

RESULTS

In the study, we developed a computational model that combined heterogeneous graph convolutional network with enhanced layer for miRNA-disease association prediction (HGCNELMDA). The major improvement of our method lies in through restarting the random walk optimized the original features of nodes and adding a reinforcement layer to the hidden layer of graph convolutional network retained similar information between nodes in the feature space. In addition, the proposed approach recalculated the influence of neighborhood nodes on target nodes by introducing the attention mechanism. The reliable performance of the HGCNELMDA was certified by the AUC of 93.47% in global leave-one-out cross-validation (LOOCV), and the average AUCs of 93.01% in fivefold cross-validation. Meanwhile, we compared the HGCNELMDA with the state‑of‑the‑art methods. Comparative results indicated that o the HGCNELMDA is very promising and may provide a cost‑effective alternative for miRNA-disease association prediction. Moreover, we applied HGCNELMDA to 3 different case studies to predict potential miRNAs related to lung cancer, prostate cancer, and pancreatic cancer. Results showed that 48, 50, and 50 of the top 50 predicted miRNAs were supported by experimental association evidence. Therefore, the HGCNELMDA is a reliable method for predicting disease-related miRNAs.

CONCLUSIONS

The results of the HGCNELMDA method in the LOOCV (leave-one-out cross validation, LOOCV) and 5-cross validations were 93.47% and 93.01%, respectively. Compared with other typical methods, the performance of HGCNELMDA is higher. Three cases of lung cancer, prostate cancer, and pancreatic cancer were studied. Among the predicted top 50 candidate miRNAs, 48, 50, and 50 were verified in the biological database HDMMV2.0. Therefore; this further confirms the feasibility and effectiveness of our method. Therefore, this further confirms the feasibility and effectiveness of our method. To facilitate extensive studies for future disease-related miRNAs research, we developed a freely available web server called HGCNELMDA is available at http://124.221.62.44:8080/HGCNELMDA.jsp .

MiRNAs in Lung Cancer: Diagnostic, Prognostic, and Therapeutic Potential

Lung cancer is the dominant emerging factor in cancer-related mortality around the globe. Therapeutic interventions for lung cancer are not up to par, mainly due to reoccurrence/relapse, chemoresistance, and late diagnosis. People are currently interested in miRNAs, which are small double-stranded (20–24 ribonucleotides) structures that regulate molecular targets (tumor suppressors, oncogenes) involved in tumorigeneses such as cell proliferation, apoptosis, metastasis, and angiogenesis via post-transcriptional regulation of mRNA. Many studies suggest the emerging role of miRNAs in lung cancer diagnostics, prognostics, and therapeutics. Therefore, it is necessary to intensely explore the miRNOME expression of lung tumors and the development of anti-cancer strategies. The current review focuses on the therapeutic, diagnostic, and prognostic potential of numerous miRNAs in lung cancer.

Bone Marrow Mesenchymal Stem Cells (BMSCs)-Originated miR-1298 Impedes the Aggressiveness of Non-Small Cell Lung Cancer by Hindering the Chemokine Receptor 4 (CXCR4)-Induced Epithelial-Mesenchymal Transition (EMT) Process

Exosomes are a subclass of extracellular vesicles, which are produced and secreted by various cells including bone marrow mesenchymal stem cells (BMSCs). BMSCs-originated exosomes can provide a beneficial microenvironment and manipulate tumor growth. However, whether BMSCs-derived miR-1298 exerts roles in NSCLC remains unclear. miR-1298 level was quantified in NSCLC tumor tissues and para-cancerous tissues and NSCLC cell lines. Cells were transfected with miR-136 mimics/miR-136 inhibitors or treatment with BMSCs-originated exosomes to measure cell biological behaviors. Our results found a diminished miR-1298 expression in NSCLC tumor specimens and cell lines. Meanwhile, miR-1298 overexpression or miR-1298 derived from BMSC-originated exosomes can restrain the proliferating feature of NSCLC cells, and impedes cell aggressiveness via hindering EMT process. Additionally, CXCR4 was a target of miR-1298. In conclusion, miR-1298 is served as a tumor suppressor gene in NSCLC and can retard the proliferating and invading behaviors of NSCLC cells by targeting CXCR4 expression, indicating that it might be a novel therapeutic target for treating NSCLC.

Predicting miRNA-disease associations via learning multimodal networks and fusing mixed neighborhood information

MOTIVATION

In recent years, a large number of biological experiments have strongly shown that miRNAs play an important role in understanding disease pathogenesis. The discovery of miRNA-disease associations is beneficial for disease diagnosis and treatment. Since inferring these associations through biological experiments is time-consuming and expensive, researchers have sought to identify the associations utilizing computational approaches. Graph Convolutional Networks (GCNs), which exhibit excellent performance in link prediction problems, have been successfully used in miRNA-disease association prediction. However, GCNs only consider 1st-order neighborhood information at one layer but fail to capture information from high-order neighbors to learn miRNA and disease representations through information propagation. Therefore, how to aggregate information from high-order neighborhood effectively in an explicit way is still challenging.

RESULTS

To address such a challenge, we propose a novel method called mixed neighborhood information for miRNA-disease association (MINIMDA), which could fuse mixed high-order neighborhood information of miRNAs and diseases in multimodal networks. First, MINIMDA constructs the integrated miRNA similarity network and integrated disease similarity network respectively with their multisource information. Then, the embedding representations of miRNAs and diseases are obtained by fusing mixed high-order neighborhood information from multimodal network which are the integrated miRNA similarity network, integrated disease similarity network and the miRNA-disease association networks. Finally, we concentrate the multimodal embedding representations of miRNAs and diseases and feed them into the multilayer perceptron (MLP) to predict their underlying associations. Extensive experimental results show that MINIMDA is superior to other state-of-the-art methods overall. Moreover, the outstanding performance on case studies for esophageal cancer, colon tumor and lung cancer further demonstrates the effectiveness of MINIMDA.

AVAILABILITY AND IMPLEMENTATION

https://github.com/chengxu123/MINIMDA and http://120.79.173.96/.

MicroRNA-20a-5p Downregulation by Atorvastatin: A Potential Mechanism Involved in Lipid-Lowering Therapy

The treatment of hypercholesterolemia is mainly based on statins. However, the response to pharmacological therapy shows high inter-individual variability, resulting in variable effects in both lipid lowering and risk reduction. Thus, a better understanding of the lipid-lowering mechanisms and response variability at the molecular level is required. Previously, we demonstrated a deregulation of the microRNA expression profile in HepG2 cells treated for 24 h with atorvastatin, using a microarray platform. In the present study, we evaluated the expression of hsa-miR-17-5p, hsa-miR-20a-5p and hsa-miR-106a-5p in hypercholesterolemic patients before and after atorvastatin treatment and in HepG2 cells treated for 24 h with atorvastatin The miRNA hsa-mir-20a-5p was repressed after atorvastatin treatment in hypercholesteremic subjects and in HepG2 cells in culture. Repression of hsa-mir-20a-5p increased LDLR gene and protein expression in HepG2 cells, while hsa-mir-20a-5p overexpression reduced LDLR gene and protein expression.

Downregulated miR-18a and miR-92a synergistically suppress non-small cell lung cancer via targeting Sprouty 4

As a novel noncoding RNA cluster, miR-17-92 cluster include six members: miR-17, miR-18a, miR-19a, miR-19b-1, miR-20a, and miR-92a. Dysregulation of miR-17-92 has been proved to be connected with the advancement of a series of human diseases, but the roles of miR-17-92 cluster in non-small cell lung cancer (NSCLC) have not been absolutely elaborated. Herein, we determined that miR-17-92 cluster were upregulated significantly in NSCLC tissues, and the cell proliferation, migration and cycle progression of NSCLC were also facilitated under the function of miR-17-92 cluster. Sprouty 4 (SPRY4) was a direct target of miR-92a, and its overexpression restrained the exacerbation of NSCLC induced by miR-92a. Furthermore, the tumor xenograft assay showed that miR-92a facilitated tumor growth by inhibiting the expression of SPRY4 and mediating Epithelial-Mesenchymal Transition (EMT) in vivo. Finally, we looked into the synergistic effects of miR-92a and miR-18a on NSCLC, and found that antagomiR-18a treatment arrested the tumor growth rate of xenografted mice markedly.

Human mesenchymal stem cell derived exosomes inhibit the survival of human melanoma cells through modulating miR-138-5p/SOX4 pathway

Melanoma, a skin cancer derived from malignant melanocytes, is characterized by high aggressiveness and mortality. However, its exact etiology is unknown. Recently, the roles of exosomes and exosomal microRNAs (miRNAs) in the progression and therapy of various disorders, including melanoma, have gained attention. We investigated the impact of miR-138-5p from exosomes released by human mesenchymal stem cells (HMSCs) on the pathogenesis of melanoma. We isolated exosomes from HMSCs (HMSC-exos) by ultracentrifugation and verified them by specific biomarkers and transmission electron microscopy. We used CCK8, flow cytometry, quantitative real-time PCR (qRT-PCR), and Western blots to investigate cell proliferation, apoptosis, and mRNA and protein levels, respectively. Additionally, we used luciferase assays to examine the relationship between miR-138-5p and SOX4. Administration of HMSC-exos dramatically repressed the growth of melanoma cells. Elevated miR-138-5p levels in HMSC-exos were linked to increased cell apoptosis, and miR-138-5p downregulation had the opposite effects on cells. SOX4 was targeted by miR-138-5p through direct binding to the SOX4 3'UTR. In melanoma tissues, miR-138-5p was downregulated, and SOX4 was upregulated and was negatively correlated. MiR-138-5p plays a crucial role in melanoma progression. The negative regulation of SOX4 transcription mediates the function of miR-138-5p. These findings provide a novel concept of melanoma pathogenesis and identify a valuable target (miR-138-5p/SOX4 axis) in treating this disease.

Approaches Toward Targeting Matrix Metalloproteases for Prognosis and Therapies in Gynecological Cancer: MicroRNAs as a Molecular Driver

Gene expression can be regulated by small non-coding RNA molecules like microRNAs (miRNAs) which act as cellular mediators necessary for growth, differentiation, proliferation, apoptosis, and metabolism. miRNA deregulation is often observed in many human malignancies, acting both as tumor-promoting and suppressing, and their abnormal expression is linked to unrestrained cellular proliferation, metastasis, and perturbation in DNA damage as well as cell cycle. Matrix Metalloproteases (MMPs) have crucial roles in both growth, and tissue remodeling in normal conditions, as well as in promoting cancer development and metastasis. Herein, we outline an integrated interactive study involving various MMPs and miRNAs and also feature a way in which these communications impact malignant growth, movement, and metastasis. The present review emphasizes on important miRNAs that might impact gynecological cancer progression directly or indirectly via regulating MMPs. Additionally, we address the likely use of miRNA-mediated MMP regulation and their downstream signaling pathways towards the development of a potential treatment of gynecological cancers.

Spectrum of microRNAs and their target genes in cancer: intervention in diagnosis and therapy

Till date, several groups have studied the mechanism of microRNA (miRNA) biogenesis, processing, stability, silencing, and their dysregulation in cancer. The miRNA coding genes recurrently go through abnormal amplification, deletion, transcription, and epigenetic regulation in cancer. Some miRNAs function as tumor promoters while few others are tumor suppressors based on the transcriptional regulation of target genes. A review of miRNAs and their target genes in a wide range of cancers is attempted in this article, which may help in the development of new diagnostic tools and intervention therapies. The contribution of miRNAs for drug sensitivity or resistance in cancer therapy and opportunities of miRNAs in cancer prognosis or diagnosis and therapy is also presented in detail.

Diagnostic value of PPARδ and miRNA-17 expression levels in patients with non-small cell lung cancer

The PPARδ gene codes protein that belongs to the peroxisome proliferator-activated receptor (PPAR) family engaged in a variety of biological processes, including carcinogenesis. Specific biological and clinical roles of PPARδ in non-small cell lung cancer (NSCLC) is not fully explained. The association of PPARα with miRNA regulators (e.g. miRNA-17) has been documented, suggesting the existence of a functional relationship of all PPARs with epigenetic regulation. The aim of the study was to determine the PPARδ and miR-17 expression profiles in NSCLC and to assess their diagnostic value in lung carcinogenesis. PPARδ and miR-17 expressions was assessed by qPCR in NSCLC tissue samples (n = 26) and corresponding macroscopically unchanged lung tissue samples adjacent to the primary lesions served as control (n = 26). PPARδ and miR-17 expression were significantly lower in NSCLC than in the control (p = 0.0001 and p = 0.0178; respectively). A receiver operating characteristic (ROC) curve analysis demonstrated the diagnostic potential in discriminating NSCLC from the control with an area under the curve (AUC) of 0.914 for PPARδ and 0.692 for miR-17. Significant increase in PPARδ expression in the control for current smokers vs. former smokers (p = 0.0200) and increase in miR-17 expression in control tissue adjacent to adenocarcinoma subtype (p = 0.0422) were observed. Overexpression of miR-17 was observed at an early stage of lung carcinogenesis, which may suggest that it acts as a putative oncomiR. PPARδ and miR-17 may be markers differentiating tumour tissue from surgical margin and miR-17 may have diagnostic role in NSCLC histotypes differentiation.

Functional and Clinical Significance of Dysregulated microRNAs in Liver Cancer

Simple Summary

Liver cancer has a high mortality rate. Here, we retrospectively discuss the current progress and dilemmas in the clinical research and treatment of liver cancer. We primarily focus on microRNAs because of their extremely high value in applications and research. We discuss whether microRNAs can be used for the development of better biomarkers and/or therapeutic drugs, and address the difficulties, requirements for improved diagnostic technologies, and side effects related to microRNA-based drugs.

Abstract

Liver cancer is the leading cause of cancer-related mortality in the world. This mainly reflects the lack of early diagnosis tools and effective treatment methods. MicroRNAs (miRNAs) are a class of non-transcribed RNAs, some of which play important regulatory roles in liver cancer. Here, we discuss microRNAs with key impacts on liver cancer, such as miR-122, miR-21, miR-214, and miR-199. These microRNAs participate in various physiological regulatory pathways of liver cancer cells, and their modulation can have non-negligible effects in the treatment of liver cancer. We discuss whether these microRNAs can be used for better clinical diagnosis and/or drug development. With the advent of novel technologies, fast, inexpensive, and non-invasive RNA-based biomarker research has become a new mainstream approach. However, the clinical application of microRNA-based markers has been limited by the high sequence similarity among them and the potential for off-target problems. Therefore, researchers particularly value microRNAs that are specific to or have special functions in liver cancer. These include miR-122, which is specifically expressed in the liver, and miR-34, which is necessary for the replication of the hepatitis C virus in liver cancer. Clinical treatment drugs have been developed based on miR-34 and miR-122 (MRX34 and Miravirsen, respectively), but their side effects have not yet been overcome. Future research is needed to address these weaknesses and establish a feasible microRNA-based treatment strategy for liver cancer.

Prolonged sub-lethal exposure to galaxolide (HHCB) and tonalide (AHTN) promotes the metastatic potential of glioblastoma tumor spheroids

Galaxolide and tonalide are well-known polycyclic musks whose intensive use without limitations in numerous cleaning, hygiene, and personal care products has resulted in widespread direct human exposure via absorption, inhalation, and oral ingestion. Latest data shows that long-term, low-dose exposure to toxic chemicals can induce unpredictable harmful effects in a variety of living systems, however, interactions between synthetic musks and brain tumours remain largely unexplored. Glioblastoma (GB) accounts for nearly half of all tumours of the central nervous system and is characterized by very poor prognosis. The aims of this study were (1) to investigate the potential effect of long-term (20-generation) single and combined application of galaxolide and tonalide at sub-lethal doses (5-2.5 u M) on the angiogenesis, invasion, and migration of human U87 cells or tumour spheroids, and (2) to explore the underlying molecular mechanisms. Random amplified polymorphic DNA assays revealed significant DNA damage and increased total mutation load in galaxolide- and/or tonalide-treated U87 cells. In those same groups, we also detected remarkable tumour spheroid invasion and up-regulation of both HIF1-α/VEGF/MMP9 and IL6/JAK2/STAT3 signals, known to have important roles in hypoxia-related angiogenesis and/or proliferation. Prolonged musk treatment further altered angio-miRNA expression in a manner consistent with poor prognosis in GB. We also detected significant over-expression of the genes Slug, Snail, ZEB1, and Vimentin, which are biomarkers of epithelial to mesenchymal transition. In addition, matrigel, transwell, and wound healing assays clearly showed that long-term sub-lethal exposure to galaxolide and/or tonalide induced invasion and migration proposing a high metastatic potential. Our results suggest that assessing expression of HIF-1a, VEGF, STAT3, and the miR-17-92 cluster in biopsy samples of GB patients who have a history of possible long-term exposure to galaxolide or tonalide could be beneficial for deciding a therapy regime. Additionally, we recommend that extensively-used hygiene and cleaning materials be selected from synthetic musk-free products, especially when used in palliative care processes for GB patients.

IPF-Fibroblast Erk1/2 Activity Is Independent from microRNA Cluster 17-92 but Can Be Inhibited by Treprostinil through DUSP1

Idiopathic pulmonary fibrosis (IPF) is a progressive terminal lung disease, and therapies aim to block fibrosis. Fibroblast proliferation is controlled by C/EBP-β, microRNA cluster 17-92 (miR17-92), and Erk1/2 mitogen-activated protein kinase. This study assessed the role of miR17-92 in IPF-fibroblast proliferation and its modification by treprostinil. Fibroblasts were isolated from eight IPF patients, five interstitial lung fibrosis patients, and seven control lungs. Fibroblasts were stimulated with TGF-β1 over 24 h. The miR17-92 expression was analyzed by RT-qPCR, and protein expression by Western blotting. TGF-β1 upregulated C/EBP-β in all fibroblasts, which was reduced by treprostinil in control-fibroblasts, but not in IPF-fibroblasts. Compared to controls, the guide strands miR-19a-3p, miR-19b-3p, miR-20a-5p, and miR-92a-3p, as well as the passenger strands miR-17-3p, miR-18-3p, miR-19a-1-5p, and miR-92a-5p were significantly increased in IPF-fibroblasts. In controls, TGF-β1 and treprostinil significantly reduced specific miR17-92 members. IPF-fibroblast proliferation was inhibited by treprostinil through increased expression of the Erk1/2 inhibitor DUSP1. These data suggest that proliferation control via miR17-92 and C/EBP-β is disrupted in IPF-fibroblasts. Therefore, the inhibition of early stages of signaling cascades or specific mitogen receptors might be less effective. However, the increased proliferation is sensitive to Erk1/2 inhibition by treprostinil-induced DUSP1.

Clinical Significance and Biological Function of miR-1274a in Non-small Cell Lung Cancer

Since the discovery of microRNAs (miRNAs) as a class of important regulatory molecules, miRNAs are involved in the occurrence and development of tumors. In this paper, we aimed to identify the role of miR-1274a in non-small cell lung cancer (NSCLC). The miR-1274a expression levels in four NSCLC cells and tissues from 125 patients were determined by qRT-PCR assays. Kaplan-Meier survival curves and Cox regression analysis were used to examine the prognostic significance of miR-1274a in NSCLC patients. The CCK-8 and Transwell assays were performed to evaluate the cell proliferation, invasion, and migration ability of NSCLC cells. The miR-1274a expression levels were significantly higher in NSCLC tissues than in adjacent normal tissues, and overexpression of miR-1274a had a poor prognosis in NSCLC patients. Functional studies in two NSCLC cell lines have shown that overexpression of miR-1274a could promote cell proliferation, migration, and invasion. miR-1274a expression levels are upregulated in NSCLC tissues, and a high expression is associated with a poor prognosis in patients with NSCLC. Moreover, miR-1274a promotes cell proliferation, migration, and invasion. Based on our findings, miR-1274a may act as a tumor miRNA in the occurrence and development of NSCLC.

Overexpression of miR-20a-5p in Tumor Epithelium Is an Independent Negative Prognostic Indicator in Prostate Cancer-A Multi-Institutional Study

Simple Summary

MicroRNAs (miRs) have critical regulatory roles in cell functions, and are involved in prostate cancer tumorigenesis. miR-20a-5p is a member of the oncogenic miR-17-92 cluster. Overexpressed miR-20a-5p has been shown to increase both cell proliferation and cell migration in cancers. The aim of our cohort study was to evaluate the prognostic role of miR-20a-5p in prostate cancer. We found miR-20a-5p associated with biochemical failure in tumor epithelium and tumor stroma. In the multivariable analysis miR-20a-5p in tumor epithelium was found to be an independent prognostic predictor for biochemical failure. In the functional studies, migration and invasion were significantly increased in miR-20a-5p transfected prostate cancer cell lines. In conclusion, high miR-20a-5p expression in tumor epithelium is a negative independent prognostic factor for biochemical failure in prostate cancer.

Abstract

Objective: assessing the prognostic role of miR-20a-5p, in terms of clinical outcome, in a large multi-institutional cohort study. Methods: Tissue microarrays from 535 patients’ prostatectomy specimens were constructed. In situ hybridization was performed to assess the expression level of miR-20a-5p in different tissue subregions: tumor stroma (TS) and tumor epithelium (TE). In vitro analysis was performed on prostate cancer cell lines. Results: A high miR-20a-5p expression was found negatively in association with biochemical failure in TE, TS and TE + TS (p = 0.001, p = 0.003 and p = 0.001, respectively). Multivariable analysis confirmed that high miR-20a-5p expression in TE independently predicts dismal prognosis for biochemical failure (HR = 1.56, 95% CI: 1.10–2.21, p = 0.014). Both DU145 and PC3 cells exhibited increased migration ability after transient overexpression of miR-20a-5p, as well as significant elevation of invasion in DU145 cells. Conclusion: A high miR-20a-5p expression in tumor epithelium is an independent negative predictor for biochemical prostate cancer recurrence.

Cucurbitacin B enhances apoptosis in gefitinib resistant non‑small cell lung cancer by modulating the miR‑17‑5p/STAT3 axis

Tyrosine kinase inhibitors, such as gefitinib, are currently widely used as targeted therapeutics for non-small cell lung cancer (NSCLC). Although drug resistance has become a major obstacle to successful treatment, mechanisms underlying resistance to gefitinib remain unclear. Therefore, the present study aimed to investigate the impact of adjunctive cucurbitacin B (CuB) on gefitinib resistance (GR) in the PC9 cell line, including identifying underlying mechanisms. Reverse transcription-quantitative PCR demonstrated significant downregulation of microRNA (miR)-17-5p expression in GR PC9 cells (PC9/GR), and this could be reversed by CuB. During combination treatment with CuB and gefitinib at IC₂₅, PC9/GR cell proliferation was downregulated, and apoptosis was upregulated. The presence of a miR-17-5p inhibitor negated the effects of CuB and gefitinib, whereas the presence of a miR-17-5p mimic enhanced them. Luciferase assays demonstrated that the hypothetical target gene, signal transducer and activator of transcription 3 (STAT3), was directly targeted by miR-17-5p. Moreover, significant elevation of the STAT3 protein and phosphorylation levels in PC9/GR cells was reversed by the addition of CuB, despite a lack of change in STAT3 transcription level. During combined treatment with CuB and gefitinib at IC₂₅, the STAT3 protein expression was negatively associated with the expression of miR-17-5p. Overexpression of STAT3 increased proliferation and decreased apoptosis and the protein levels of apoptosis-related factors cleaved caspase-3 and cleaved caspase-9 of PC9/GR cells. Findings indicated that STAT3 protein and phosphorylation levels became elevated in response to gefitinib, and that CuB-induced miR-17-5p expression led to STAT3 degradation, thereby ameliorating GR. In summary, CuB reduced the proliferation of GR PC9 cells by modulating the miR-17-5p/STAT3 axis, and may represent a promising potential novel strategy for the reversal of GR.

New biomarkers in peripheral blood of patients with ovarian cancer: high expression levels of miR-16-5p, miR-17-5p, and miR-638

OBJECTIVES

Ovarian cancer is one of the most fatal gynecologic malignities. miR-16-5p, miR-17-5p, and miR-638 genes were found to have been associated with ovarian cancer in accordance with the data obtained from the previous microarray research performed by Tuncer et al. (J Ovarian Res 13(1):99, 2020). The expression levels of these miRNAs in the peripheral blood samples of 142 ovarian cancer patients, and 97 healthy controls were investigated for performing the validation, and to identify whether these genes were the possible biomarkers to be used in the early diagnosis of high-risk ovarian cancer patients, and in the prognosis of patients.

METHODS

The miRNA expression analysis was performed using the miRNA-specific cDNA synthesis, and real-time PCR methods following the RNA isolation from the peripheral blood lymphocytes.

RESULTS

miR-16-5p, miR-17-5p, and miR-638 miRNA gene expression levels were found to have twofold higher expression levels in patient groups compared with the gene expression levels in healthy controls, and were statistically significant (p < 0.05). In addition, the comparison of the miRNA expression levels with the clinical data of patients showed that there was a significant difference with smoking history and the increased expression level of miR-17-5 (p: 0.007). There was a significant difference between the increased expression level of miR-638 with the locally advanced stage, and abdominal/pelvic metastatic patients (p: 0.03).

CONCLUSIONS

The obtained data suggest that miR-16-5p, miR-17-5p, and miR-638 molecules might be the noninvasive biomarkers in identifying the ovarian cancer. However, the investigation and monitoring of the changeability of these biomarkers in benign ovarian diseases, and during the treatment must be performed in future studies for identifying the accurate diagnostic, and prognostic features of miRNAs.

The effect and mechanism of miR-607/CANT1 axis in lung squamous carcinoma

Lung squamous carcinoma (LUSC) is the second most frequent subtype of non-small cell lung cancer. Rarely gene alterations are identified in LUSC. Therefore, identifying LUSC-related genes to explain the relevant molecular mechanism is urgently needed. A potential biomarker, calcium-activated nucleotidase 1 (CANT1), was elevated in tissues of LUSC patients relative to normal cases based on the TCGA and/or GTEx database. CCK-8 and transwell tests were then implemented to measure the proliferative, invasive and migratory capacities, and showed that knockdown of CANT1 blocked LUSC cells proliferation. miR-607, predicted as an upstream factor for CANT1, was declined in LUSC using TargetScan analysis and luciferase activity test. Low miR-607 expression was related with unfavorable outcomes of LUSC patients. Moreover, miR-607 downregulation elevated cell viability, invasion and migration in LUSC cells, which was antagonized by si-CANT1. GEPIA website was accessed to estimate the relevance between CANT1 and epithelial-mesenchymal transition (EMT)-related positive factors. The protein levels of Fibronectin, Vimentin, Snail and β-catenin were altered due to the abnormal CANT1 and miR-607 expression. Together, these data unveiled that miR-607/CANT1 pair may exert a vital role in the progression of LUSC through mediating EMT process, which would furnish an available therapeutic therapy for LUSC.

Cascades between miRNAs, lncRNAs and the NF-κB signaling pathway in gastric cancer (Review)

Gastric cancer is a common digestive tract malignancy that is mainly treated with surgery combined with perioperative adjuvant chemoradiotherapy and biological targeted therapy. However, the diagnosis rate of early gastric cancer is low and both postoperative recurrence and distant metastasis are thorny problems. Therefore, it is essential to study the pathogenesis of gastric cancer and search for more effective means of treatment. The nuclear factor-κB (NF-κB) signaling pathway has an important role in the occurrence and development of gastric cancer and recent studies have revealed that microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are able to regulate this pathway through a variety of mechanisms. Understanding these interrelated molecular mechanisms is helpful in guiding improvements in gastric cancer treatment. In the present review, the functional associations between miRNAs, lncRNAs and the NF-κB signaling pathway in the occurrence, development and prognosis of gastric cancer were discussed. It was concluded that miRNAs and lncRNAs have complex relations with the NF-κB signaling pathway in gastric cancer. miRNAs/target genes/NF-κB/target proteins, signaling molecules/NF-κB/miRNAs/target genes, lncRNAs/miRNAs/NF-κB/genes or mRNAs, lncRNAs/target genes/NF-Κb/target proteins, and lncRNAs/NF-κB/target proteins cascades are all important factors in the occurrence and development of gastric cancer.

LKB1 Down-Modulation by miR-17 Identifies Patients With NSCLC Having Worse Prognosis Eligible for Energy-Stress-Based Treatments

INTRODUCTION

Preclinical models recently unveiled the vulnerability of LKB1/KRAS comutated NSCLC to metabolic stress-based treatments. Because miR-17 is a potential epigenetic regulator of LKB1, we hypothesized that wild-type LKB1 (LKB1^WT) NSCLC with high miR-17 expression may be sensitive to an energetic stress condition, and eligible for metabolic frailties-based therapeutic intervention.

METHODS

We took advantage of NSCLC cell lines with different combinations of KRAS mutation and LKB1 deletion and of patient-derived xenografts (PDXs) with high (LKB1^WT/miR-17 high) or low (LKB1^WT/miR-17 low) miR-17 expression. We evaluated LKB1 pathway impairment and apoptotic response to metformin. We retrospectively evaluated LKB1 and miR-17 expression levels in tissue specimens of patients with NSCLC and PDXs. In addition, a lung cancer series from The Cancer Genome Atlas data set was analyzed for miR-17 expression and potential correlation with clinical features.

RESULTS

We identified miR-17 as an epigenetic regulator of LKB1 in NSCLC and confirmed targeting of miR-17 to LKB1 3' untranslated region by luciferase reporter assay. We found that miR-17 overexpression functionally impairs the LKB1/AMPK pathway. Metformin treatment prompted apoptosis on miR-17 overexpression only in LKB1^WT cell lines, and in LKB1^WT/miR-17 high PDXs. A retrospective analysis in patients with NSCLC revealed an inverse correlation between miR-17 and LKB1 expression and highlighted a prognostic role of miR-17 expression in LKB1^WT patients, which was further confirmed by The Cancer Genome Atlas data analysis.

CONCLUSIONS

We identified miR-17 as a mediator of LKB1 expression in NSCLC tumors. This study proposes a miR-17 expression score potentially exploitable to discriminate LKB1^WT patients with NSCLC with impaired LKB1 expression and poor outcome, eligible for energy-stress-based treatments.

Bioinformatics Analysis of Dysregulated MicroRNA-Messenger RNA Networks in Small Cell Lung Cancer

The present study aimed to identify a key module of differentially expressed miRNAs (DE-miRNAs) together with the corresponding differentially expressed mRNAs (DE-mRNAs) within small cell lung cancer (SCLC). Linear models were applied to ascertain the DE-miRNAs and DE-mRNAs in SCLC versus matched non-carcinoma samples obtained from the RNA expression datasets of GSE19945, GSE74190 and GSE6044. The common DE-miRNAs were identified using the Venn plot. Then, 3 databases were used to retrieve the DE-miRNAs target genes, and the intersection was taken for validating the shared target genes. Besides, Cytoscape was utilized for constructing the miRNAmRNA network for SCLC. Finally, a key module of five DE-miRNAs and four hub genes was determined based on the degree. In addition, the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted for exploring those hub genes in terms of their functions along with the involved signal transduction pathways. Altogether 106 shared DE-miRNAs were identified, which were used to predict 63 common target genes. In addition, a key module of five DE-miRNAs (hsa-miR-17-5p, hsa-miR-20a-5p, hsa-miR-20b-5p, hsa-miR-93-5p and hsa-miR- 106b-5p) and four hub genes (SOX4, DPYSL2, TGFBR2 and F3) were extracted from the miRNAmRNA network according to their degree. Finally, the hub genes were subjected to GO as well as KEGG analysis, which revealed that cell cycle G1/S phase transition, the extracellular matrix, and cellular senescence signaling pathways exerted vial parts during SCLC progression. A key module of five DE-miRNAs and four hub genes may be potentially used as clinical biomarkers to predict SCLC.