Emerging molecular functions of microRNA-124: Cancer pathology and therapeutic implications

The biomarkers for maintenance Cancer stem cell features can be applicable in precision medicine of head and neck squamous cell carcinoma

Cancer stem cells (CSCs) play a crucial role in tumor relapse, proliferation, invasion, and drug resistance in head and neck squamous cell carcinoma (HNSCC). This narrative review aims to synthesize data from articles published between 2019 and 2023 on biomarkers for detecting CSCs in HNSCC and changes in molecular pathways, genetics, epigenetics, and non-coding RNAs (ncRNAs) in CSCs relevant to precision medicine approaches in HNSCC management. The search encompassed 41 in vitro studies and 22 clinical studies. CSCs exhibit diverse molecular profiles and unique biomarker expression patterns, offering significant potential for HNSCC diagnosis, treatment, and prognosis, thereby enhancing patient survival. Their remarkable self-renewal ability and adaptability are closely linked to tumorigenicity development and maintenance. Assessing biomarkers before and after therapy can aid in identifying various cell types associated with cancer progression and relapse. Screening for CSCs, senescent tumor cells, and cells correlated with the senescence process post-treatment has proven highly beneficial. However, the clinical application of precision medicine in HNSCC management is hindered by the lack of specific and definitive CSC biomarkers. Furthermore, our limited understanding of CSC plasticity, governed by genomic, transcriptomic, and epigenomic alterations during tumorigenesis, as well as the bidirectional interaction of CSCs with the tumor microenvironment, underscores the need for further research. Well-designed studies involving large patient cohorts are, therefore, essential to establish a standardized protocol and address these unresolved queries.

MiR-184 targeting FOXO1 regulates host-cell oxidative stress induced by Chlamydia psittaci via the Wnt/β-catenin signaling pathway

Chlamydia psittaci is a human pathogen that causes atypical pneumonia after zoonotic transmission. We confirmed that C. psittaci infection induces oxidative stress in human bronchial epithelial (HBEs) cells and explored how this is regulated through miR-184 and the Wnt/β-catenin signaling pathway. miR-184 mimic, miR-184 inhibitor, FOXO1 siRNA, or negative control sequence was transfected into HBE cells cultured in serum-free medium using Lipofectamine 2000. Then, prior to the cells were infected with C. psittaci 6BC, and the cells were treated with or without 30 µM Wnt/β-catenin inhibitor ICG-001. Quantification of reactive oxygen species, malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione was carried out according to the manufacturer's protocol using a corresponding assay kit. The outcome of both protein and gene was measured by western blotting or real-time fluorescence quantitative PCR. In C. psittaci-infected HBE cells, miR-184 was upregulated, while one of its target genes, FOXO1, was downregulated. ROS and MDA levels increased, while SOD and GSH contents decreased after C. psittaci infection. When miR-184 expression was downregulated, the level of oxidative stress caused by C. psittaci infection was reduced, and the Wnt/β-catenin signaling pathway was inhibited. The opposite results were seen when miR-184 mimic was used. Transfecting with FOXO1 siRNA reversed the effect of miR-184 inhibitor. Moreover, when the Wnt/β-catenin-specific inhibitor ICG-001 was used, the level of oxidative stress induced by C. psittaci infection was significantly suppressed. miR-184 can target FOXO1 to promote oxidative stress in HBE cells following C. psittaci infection by activation of the Wnt/β-catenin signaling pathway.

Inhibition of miR-495-3p ameliorated sevoflurane induced damage through BDNF/ERK/CREB signaling pathways in HT22 cells

OBJECTIVE

Sevoflurane is used in anesthesia for surgery including in organ transplantation. We investigated the role of a non-coding single-stranded microRNA, miR-495-3p, in the sevoflurane-induced neurotoxicity using a mouse hippocampal neuronal cell line (HT22).

METHODS

The levels of miR-495-3p in sevoflurane-exposed mice and HT22 cells were determined via RT-qPCR. The role of miR-495-3p on cell viability and apoptosis were determined by CCK-8 and flow cytometric assay, respectively. Western blotting was explored to measure levels of Bax, Bcl-2, active caspase 3, BDNF, p-ERK/ERK and p-CREB/CREB in HT22 cells. ELISA assay was used to examine the levels of reactive oxygen species (ROS), superoxide dismutase (SOD) and glutathione peroxidase (GPX) in cells. Dual luciferase reporter assay was used to explore the interaction of miR-495-3p and BDNF.

RESULTS

The level of miR-495-3p was increased sevoflurane-exposed mice and in sevoflurane-treated HT22 cells. Downregulation of miR-495-3p inhibited sevoflurane-induced apoptosis and promoted cell proliferation by upregulating the proteins of Bcl-2 and downregulating the expressions of Bax and active caspase-3 in HT22 cells. In addition, inhibition of miR-495-3p alleviated sevoflurane-induced oxidative injuries in HT22 cells via decline of ROS and upregulation of SOD and GPX. MiR-495-3p can inhibit the ERK/CREB pathway by targeting BDNF.

CONCLUSION

Downregulation of miR-495-3p can decrease oxidative status in HT22 cells and alleviate sevoflurane-induced cytotoxicity through stimulating the BDNF/ERK/CREB pathway.

Regulation of the Key Epithelial Cancer Suppressor miR-124 Function by Competing Endogenous RNAs

A decrease in the miR-124 expression was observed in various epithelial cancers. Like a classical suppressor, miR-124 can inhibit the translation of multiple oncogenic proteins. Epigenetic mechanisms play a significant role in the regulation of miR-124 expression and involve hypermethylation of the MIR-124-1/-2/-3 genes and the effects of long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) according to the model of competing endogenous RNAs (ceRNAs). More than 40 interactomes (lncRNA/miR-124/mRNA) based on competition between lncRNAs and mRNAs for miR-124 binding have been identified in various epithelial cancers. LncRNAs MALAT1, NEAT1, HOXA11-AS, and XIST are the most represented in these axes. Fourteen axes (e.g., SND1-IT1/miR-124/COL4A1) are involved in EMT and/or metastasis. Moreover, eight axes (e.g., OIP5-AS1/miR-124-5p/IDH2) are involved in key pathways, such as Wnt/b-catenin, E2F1, TGF-β, SMAD, ERK/MAPK, HIF-1α, Notch, PI3K/Akt signaling, and cancer cell stemness. Additionally, 15 axes impaired patient survival and three axes reduced chemo- or radiosensitivity. To date, 14 cases of miR-124 regulation by circRNAs have been identified. Half of them involve circHIPK3, which belongs to the exonic ecircRNAs and stimulates cell proliferation, EMT, autophagy, angiogenesis, and multidrug resistance. Thus, miR-124 and its interacting partners may be considered promising targets for cancer therapy.

The Targeting of Noncoding RNAs by Quercetin in Cancer Prevention and Therapy

The dietary flavonoid quercetin is ubiquitously distributed in fruits, vegetables, and medicinal herbs. Quercetin has been a focal point in recent years due to its versatile health-promoting benefits and high pharmacological values. It has well documented that quercetin exerts anticancer actions by inhibiting cell proliferation, inducing apoptosis, and retarding the invasion and metastasis of cancer cells. However, the exact mechanism of quercetin-mediated cancer chemoprevention is still not fully understood. With the advances in high-throughput sequencing technologies, the intricate oncogenic signaling networks have been gradually characterized. Increasing evidence on the close association between noncoding RNA (ncRNAs) and cancer etiopathogenesis emphasizes the potential of ncRNAs as promising molecular targets for cancer treatment. Available experimental studies indicate that quercetin can dominate multiple cancer-associated ncRNAs, hence repressing carcinogenesis and cancer development. Thus, modulation of ncRNAs serves as a key mechanism responsible for the anticancer effects of quercetin. In this review, we focus on the chemopreventive effects of quercetin on cancer pathogenesis by targeting cancer-relevant ncRNAs, supporting the viewpoint that quercetin holds promise as a drug candidate for cancer chemoprevention and chemotherapy. An in-depth comprehension of the interplay between quercetin and ncRNAs in the inhibition of cancer development and progression will raise the possibility of developing this bioactive compound as an anticancer agent that could be highly efficacious and safe in clinical practice.

The roles of microRNAs played in lung diseases via regulating cell apoptosis

MicroRNAs (miRNAs) are a type of endogenous non-coding short-chain RNA, which plays a crucial role in the regulation of many essential cellular functions, including cellular migration, proliferation, invasion, autophagy, oxidative stress, apoptosis, and differentiation. The lung can be damaged by pathogenic microorganisms, as well as physical or chemical factors. Research has confirmed that miRNAs and lung cell apoptosis can affect the development and progression of several lung diseases. This article reviews the role of miRNAs in the development of lung disease through regulating host cell apoptosis.

lncRNA PVT1 promotes cetuximab resistance of head and neck squamous cell carcinoma cells by inhibiting miR-124-3p

BACKGROUND

Cetuximab has been widely used in the clinical treatment of head and neck squamous cell carcinoma (HNSCC). However, whether long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) is correlated with cetuximab resistance remains unclear.

METHODS

Western blot and qRT-PCR were performed to quantify the levels of genes and proteins, respectively. Cell functions were measured using Cell Counting Kit-8 (CCK-8), Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and flow cytometry assays. The methylation level was tested using methylation-specific PCR (MSP).

RESULTS

PVT1 was upregulated and positively correlated with the poor prognosis of HNSCC. PVT1 overexpression markedly promoted the survival and weakened the cetuximab sensitivity of HNSCC cells, while miR-124-3p overexpression showed opposite effects. Mechanistically, the silence of PVT1 indirectly promoted miR-124-3p expression by reducing its promoter methylation. Importantly, miR-124-3p overexpression impeded the regulatory roles of PVT1 overexpression.

CONCLUSION

PVT1 decreased the sensitivity of HNSCC cells to cetuximab by enhancing methylation-mediated inhibition of miR-124-3p, which might provide a new insight for the cetuximab chemoresistance of HNSCC.

The Role of MiR-124 in Bladder Cancer – A Review of the Literature

MicroRNAs (miRNAs) are a group of non-coding RNA molecules that have an important role in modulating the expression of genes involved in regulating cellular functions. A growing number of studies suggest the abnormal expression of microRNAs in different types of cancer cells. MiRNA-124 is a microRNA that is down-regulated in many types of cancer cells, including bladder cancer. Our objective is to provide a review of the key publications that studied the effect of miR-124 on bladder cancer. This review focus on the targets and different pathways of miR-124 that were identified in various studies and differences between their expressions in normal urothelium and tumor tissues. We also include data regarding urinary methylations levels of miR-124 and their role in bladder cancer diagnosis and prognosis. Subsequently, we establish future perspectives of miR-124 research and its promising role in bladder cancer.

Roles of MicroRNAs in Bone Destruction of Rheumatoid Arthritis

As an important pathological result of rheumatoid arthritis (RA), bone destruction will lead to joint injury and dysfunction. The imbalance of bone metabolism caused by increased osteoclast activities and decreased osteoblast activities is the main cause of bone destruction in RA. MicroRNAs (MiRNAs) play an important role in regulating bone metabolic network. Recent studies have shown that miRNAs play indispensable roles in the occurrence and development of bone-related diseases including RA. In this paper, the role of miRNAs in regulating bone destruction of RA in recent years, especially the differentiation and activities of osteoclast and osteoblast, is reviewed. Our results will not only help provide ideas for further studies on miRNAs’ roles in regulating bone destruction, but give candidate targets for miRNAs-based drugs research in bone destruction therapy of RA as well.

Prominent roles of microRNA-142 in cancer

MicroRNAs (miRNAs) are single-stranded non-coding RNAs that regulate gene expression post-transcriptionally via mRNA degradation, or translational repression. They have important roles in normal development and homeostasis maintenance. Many studies have revealed that aberrant expression of miRNAs is associated with development of pathological conditions, including cancers. MiRNAs can either promote or suppress tumorigenesis based on the regulation of gene expression by targeting multiple molecules. In recent years, several miRNAs have been reported to be dysregulated in various cancers. Most recent findings have shown that miR-142 gene, located at chromosome 17q22, is involved in cellular migration, proliferation, and apoptosis in different human cancers. The present review discusses some molecular mechanisms and the expression status of miRNA-142 in the pathogenesis of various cancers.

Small and Long Non-coding RNAs as Functional Regulators of Bone Homeostasis, Acting Alone or Cooperatively

Emerging knowledge indicates that non-coding RNAs, including microRNAs (miRNAs) and long-noncoding RNAs (lncRNAs), have a pivotal role in bone development and the pathogenesis of bone-related disorders. Most recently, miRNAs have started to be regarded as potential biomarkers or targets for various sets of diseases, while lncRNAs have gained attention as a new layer of gene expression control acting through versatile interactions, also with miRNAs. The rapid development of RNA sequencing techniques based on next-generation sequencing (NGS) gives us better insight into molecular pathways regulated by the miRNA-lncRNA network. In this review, we summarize the current knowledge related to the function of miRNAs and lncRNAs as regulators of genes that are crucial for proper bone metabolism and homeostasis. We have characterized important non-coding RNAs and their expression signatures, in relationship to bone. Analysis of the biological function of miRNAs and lncRNAs, as well as their network, will pave the way for a better understanding of the pathogenesis of various bone disorders. We also think that this knowledge may lead to the development of innovative diagnostic tools and therapeutic approaches for bone-related disorders.