MicroRNA-98-5p Inhibits Cell Proliferation and Induces Cell Apoptosis in Hepatocellular Carcinoma via Targeting IGF2BP1

The m6A reader IGF2BP1 contributes to the activation of hepatic stellate cells through facilitating TUBB4B mRNA stabilization

The m6A reader insulin-like growth factor-2 mRNA-binding protein 1 (IGF2BP1) is involved in multiple pathophysiological processes through enhanced expression of the proteins encoded by their target mRNAs. However, the functional role of IGF2BP1-mediated m6A in liver fibrosis remains elusive. Here, we report that IGF2BP1 is highly expressed in activated hepatic stellate cells (HSCs), the major driver of fibrogenesis, and TUBB4B is identified as a potential target of IGF2BP1 by re-analysis of the RNA-seq, RIP-seq, and m6A-seq data. The relevant findings were subsequently demonstrated by a series of molecular and cellular evidences. The knockdown of IGF2BP1 or TUBB4B and pharmacological inhibition of TUBB4B by mebendazole treatments significantly suppress the proliferation, migration, and activation of HSCs. Mechanistically, IGF2BP1 upregulates TUBB4B expression through stabilizing TUBB4B in an m6A-dependent manner, and TUBB4B induces liver fibrosis by activating the FAK signaling pathway. Collectively, our results indicate that targeting IGF2BP1/TUBB4B/FAK axis in HSCs could be a promising therapeutic approach for liver fibrosis.

MicroRNAs in Hepatocellular Carcinoma Pathogenesis: Insights into Mechanisms and Therapeutic Opportunities

Hepatocellular carcinoma (HCC) presents a significant global health burden, with alarming statistics revealing its rising incidence and high mortality rates. Despite advances in medical care, HCC treatment remains challenging due to late-stage diagnosis, limited effective therapeutic options, tumor heterogeneity, and drug resistance. MicroRNAs (miRNAs) have attracted substantial attention as key regulators of HCC pathogenesis. These small non-coding RNA molecules play pivotal roles in modulating gene expression, implicated in various cellular processes relevant to cancer development. Understanding the intricate network of miRNA-mediated molecular pathways in HCC is essential for unraveling the complex mechanisms underlying hepatocarcinogenesis and developing novel therapeutic approaches. This manuscript aims to provide a comprehensive review of recent experimental and clinical discoveries regarding the complex role of miRNAs in influencing the key hallmarks of HCC, as well as their promising clinical utility as potential therapeutic targets.

MicroRNA-98 as a novel diagnostic marker and therapeutic target in cancer patients

The progress of cancer treatment methods in the last decade has significantly reduced mortality rate among these patients. Nevertheless, cancer is still recognized as one of the main causes of human deaths. One of the main reasons for the high death rate in cancer patients is the late diagnosis in the advanced tumor stages. Therefore, it is necessary to investigate the molecular biology of tumor progressions in order to introduce early diagnostic markers. MicroRNAs (miRNAs) have an important role in regulating cellular processes associated with tumor progression. Due to the high stability of miRNAs in body fluids, they are widely used as non-invasive markers in the early tumor diagnosis. Since, deregulation of miR-98 has been reported in a wide range of cancers, we investigated the molecular mechanisms of miR-98 during tumor progression. It has been reported that miR-98 mainly inhibits the tumor growth by the modulation of transcription factors and signaling pathways. Therefore, miR-98 can be introduced as a tumor marker and therapeutic target among cancer patients.

N6-Methyladenosine Methylation of mRNA in Cell Apoptosis

Apoptosis, a highly controlled homeostatic mechanism that eliminates single cells without destroying tissue function, occurs during growing development and senescence. N6-methyladenosine (m6A), as the most common internal modification of eukaryotic mRNA, fine-tunes gene expression by regulating many aspects of mRNA metabolism, such as splicing, nucleation, stability, translation, and degradation. Remarkably, recent reports have indicated that aberrant methylation of m6A-related RNA may directly or indirectly influence the expression of apoptosis-related genes, thus regulating the process of cell apoptosis. In this review, we summarized the relationship between m6A modification and cell apoptosis, especially its role in the nervous system, and analyzed the limitations of the current research.

MicroRNA-98: the multifaceted regulator in human cancer progression and therapy

MicroRNA-98 (miR-98) stands as an important molecule in the intricate landscape of oncology. As a subset of microRNAs, these small non-coding RNAs have accompanied a new era in cancer research, underpinning their significant roles in tumorigenesis, metastasis, and therapeutic interventions. This review provides a comprehensive insight into the biogenesis, molecular properties, and physiological undertakings of miR-98, highlighting its double-edged role in cancer progression-acting both as a tumor promoter and suppressor. Intriguingly, miR-98 has profound implications for various aspects of cancer progression, modulating key cellular functions, including proliferation, apoptosis, and the cell cycle. Given its expression patterns, the potential of miR-98 as a diagnostic and prognostic biomarker, especially in liquid biopsies and tumor tissues, is explored, emphasizing the hurdles in translating these findings clinically. The review concludes by evaluating therapeutic avenues to modulate miR-98 expression, addressing the challenges in therapy resistance, and assessing the efficacy of miR-98 interventions. In conclusion, while miR-98's involvement in cancer showcases promising diagnostic and therapeutic avenues, future research should pivot towards understanding its role in tumor-stroma interactions, immune modulation, and metabolic regulation, thereby unlocking novel strategies for cancer management.

Exosomal lncRNA HEIH, an essential communicator for hepatocellular carcinoma cells and macrophage M2 polarization through the miR-98-5p/STAT3 axis

Part of human long noncoding RNAs (lncRNAs) has been elucidated to play an essential role in the carcinogenesis and progression of hepatocellular carcinoma (HCC), a type of malignant tumor with poor outcomes. Tumor-derived exosomes harboring lncRNAs have also been implicated as crucial mediators to orchestrate biological functions among neighbor tumor cells. The recruitment of tumor-associated macrophages (TAMs) exerting M2-like phenotype usually indicates the poor prognosis. Yet, the precise involvement of tumor-derived lncRNAs in cross-talk with environmental macrophages has not been fully identified. In this study, we reported the aberrantly overexpressed HCC upregulated EZH2-associated lncRNA (HEIH) in tumor tissues and cell lines was positively correlated with poor prognosis, as well as enriched exosomal HEIH levels in blood plasma and cell supernatants. Besides, HCC cell-derived exosomes transported HEIH into macrophages for triggering macrophage M2 polarization, thereby in turn promoting the proliferation, migration, and invasion of HCC cells. Mechanistically, HEIH acted as a miRNA sponge for miR-98-5p to up-regulate STAT3, which was then further verified in the tumor xenograft models. Collectively, our study provides the evidence for recognizing tumor-derived exosomal lncRNA HEIH as a novel regulatory function through targeting miR-98-5p/STAT3 axis in environmental macrophages, which may shed light on the complicated tumor microenvironment among tumor and immune cells for HCC treatment.

IGF2BPs as novel m6A readers: Diverse roles in regulating cancer cell biological functions, hypoxia adaptation, metabolism, and immunosuppressive tumor microenvironment

m6A methylation is the most frequent modification of mRNA in eukaryotes and plays a crucial role in cancer progression by regulating biological functions. Insulin-like growth factor 2 mRNA-binding proteins (IGF2BP) are newly identified m6A 'readers'. They belong to a family of RNA-binding proteins, which bind to the m6A sites on different RNA sequences and stabilize them to promote cancer progression. In this review, we summarize the mechanisms by which different upstream factors regulate IGF2BP in cancer. The current literature analyzed here reveals that the IGF2BP family proteins promote cancer cell proliferation, survival, and chemoresistance, inhibit apoptosis, and are also associated with cancer glycolysis, angiogenesis, and the immune response in the tumor microenvironment. Therefore, with the discovery of their role as 'readers' of m6A and the characteristic re-expression of IGF2BPs in cancers, it is important to elucidate their mechanism of action in the immunosuppressive tumor microenvironment. We also describe in detail the regulatory and interaction network of the IGF2BP family in downstream target RNAs and discuss their potential clinical applications as diagnostic and prognostic markers, as well as recent advances in IGF2BP biology and associated therapeutic value.

Serum microRNA Profiles and Pathways in Hepatitis B-Associated Hepatocellular Carcinoma: A South African Study

The incidence and mortality of hepatocellular carcinoma (HCC) in Sub-Saharan Africa is projected to increase sharply by 2040 against a backdrop of limited diagnostic and therapeutic options. Two large South African-based case control studies have developed a serum-based miRNome for Hepatitis B-associated hepatocellular carcinoma (HBV-HCC), as well as identifying their gene targets and pathways. Using a combination of RNA sequencing, differential analysis and filters including a unique molecular index count (UMI) ≥ 10 and log fold change (LFC) range > 2: <-0.5 (p < 0.05), 91 dysregulated miRNAs were characterized including 30 that were upregulated and 61 were downregulated. KEGG analysis, a literature review and other bioinformatic tools identified the targeted genes and HBV-HCC pathways of the top 10 most dysregulated miRNAs. The results, which are based on differentiating miRNA expression of cases versus controls, also develop a serum-based miRNA diagnostic panel that indicates 95.9% sensitivity, 91.0% specificity and a Youden Index of 0.869. In conclusion, the results develop a comprehensive African HBV-HCC miRNome that potentially can contribute to RNA-based diagnostic and therapeutic options.

Regulatory mechanisms and therapeutic implications of insulin-like growth factor 2 mRNA-binding proteins, the emerging crucial m6A regulators of tumors

Insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) serve essential biological functions as post-transcriptional performers, participating in the acquisition or maintenance of tumor hallmarks due to their distinct protein structures. Emerging evidence indicates that IGF2BPs belong to the class III type of RNA N6-methyladenosine (m6A) modification readers, controlling RNA stability, storage, localization, metabolism, and translation in multiple vital bioprocesses, particularly tumorigenesis and tumor progression. Here, we discuss the underlying regulatory mechanisms and pathological functions of IGF2BPs which act as m6A readers in the context of tumor pathogenesis and multidrug resistance. Furthermore, we highlight the potential of IGF2BPs as drug targets in clinical tumor treatment. Hence, precise and novel tumor therapeutic approaches could be uncovered by targeting epigenetic heterogeneity.

Downregulated liver-elevated long intergenic noncoding RNA (LINC02428) is a tumor suppressor that blocks KDM5B/IGF2BP1 positive feedback loop in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumor with high mortality and poor prognoses worldwide. Many studies have reported that long noncoding RNAs (lncRNAs) are related to the progression and prognosis of HCC. However, the functions of downregulated liver-elevated (LE) lncRNAs in HCC remain elusive. Here we report the roles and mechanisms of downregulated LE LINC02428 in HCC. Downregulated LE lncRNAs played significant roles in HCC genesis and development. LINC02428 was upregulated in liver tissues compared with other normal tissues and showed low expression in HCC. The low expression of LINC02428 was attributed to poor HCC prognosis. Overexpressed LINC02428 suppressed the proliferation and metastasis of HCC in vitro and in vivo. LINC02428 was predominantly located in the cytoplasm and bound to insulin-like growth factor-2 mRNA-binding protein 1 (IGF2BP1) to prevent it from binding to lysine demethylase 5B (KDM5B) mRNA, which decreased the stability of KDM5B mRNA. KDM5B was found to preferentially bind to the promoter region of IGF2BP1 to upregulate its transcription. Therefore, LINC02428 interrupts the KDM5B/IGF2BP1 positive feedback loops to inhibit HCC progression. The KDM5B/IGF2BP1 positive feedback loop is involved in tumorigenesis and progression of HCC.

Epi-miRNAs: Modern mediators of methylation status in human cancers

Methylation of the fundamental macromolecules, DNA/RNA, and proteins, is remarkably abundant, evolutionarily conserved, and functionally significant in cellular homeostasis and normal tissue/organism development. Disrupted methylation imprinting is strongly linked to loss of the physiological equilibrium and numerous human pathologies, and most importantly to carcinogenesis, tumor heterogeneity, and cancer progression. Mounting recent evidence has documented the active implication of miRNAs in the orchestration of the multicomponent cellular methylation machineries and the deregulation of methylation profile in the epigenetic, epitranscriptomic, and epiproteomic levels during cancer onset and progression. The elucidation of such regulatory networks between the miRNome and the cellular methylation machineries has led to the emergence of a novel subclass of miRNAs, namely "epi-miRNAs" or "epi-miRs." Herein, we have summarized the existing knowledge on the functional role of epi-miRs in the methylation dynamic landscape of human cancers and their clinical utility in modern cancer diagnostics and tailored therapeutics. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Hepatitis B Virus Surface Antigen Promotes Stemness of Hepatocellular Carcinoma through Regulating MicroRNA-203a

BACKGROUND AND AIMS

Patients with persistent positive hepatitis B surface antigen (HBsAg), even with a low HBV-DNA load, have a higher risk of hepatocellular carcinoma (HCC) than those without HBV infection. Given that tumor stemness has a critical role in the occurrence and maintenance of neoplasms, this study aimed to explore whether HBsAg affects biological function and stemness of HCC by regulating microRNA, and to explore underlying mechanisms.

METHODS

We screened out miR-203a, the most significant down-regulated microRNA in the microarray analysis of HBsAg-positive samples and focused on that miRNA in the ensuing study. In vitro and in vivo functional experiments were performed to assess its regulatory function. The effect of miR-203a on stemness and the possible correlation with BMI1 were analyzed in this study.

RESULTS

MiR-203a was significantly down-regulated in HBsAg-positive HCC with the sharpest decrease shown in microarray analysis. The negative correlation between miR-203a and HBsAg expression was confirmed by quantitative real-time PCR after stimulation or overexpression/knockdown of HBsAg in cells. We demonstrated the function of miR-203a in inhibiting HCC cell proliferation, migration, clonogenic capacity, and tumor development in vivo. Furthermore, the overexpression of miR-203a remarkably increases the sensitivity of tumor cells to 5-FU treatment and decreases the proportion of HCC cells with stem markers. In concordance with our study, the survival analysis of both The Cancer Genome Atlas database and samples in our center indicated a worse prognosis in patients with low level of miR-203a. We also found that BMI1, a gene maintains the self-renewal capacity of stem cells, showed a significant negative correlation with miR-203a in HCC specimen (p<0.001). Similarly, opposite BMI1 changes after overexpression/knockdown of miR-203a were also confirmed in vitro. Dual luciferase reporting assay suggested that miR-203a may regulate BMI1 expression by direct binding.

CONCLUSIONS

HBsAg may promote the development of HCC and tumor stemness by inhibiting miR-203a, resulting in poor prognosis. miR-203a may serve as a crucial treatment target in HBsAg-positive HCC. More explicit mechanistic studies and animal experiments need to be conducted as a next step.

Clinical application study on miR-98-5p as a prognostic biomarker in hepatocellular carcinoma

BACKGROUND

On the one hand, to investigate the targeted regulation of miR-98-5p on heparin-binding epidermal growth factor-like growth factor (HBEGF) in patients with hepatocellular carcinoma (HCC). On the other hand, elucidate the predictive effect of miR-98-5p combined with magnetic resonance imaging (MRI) data on the clinical prognosis of HCC patients.

METHODS

Serum samples from 98 HCC patients and 54 healthy subjects were selected in order to detect miR-98-5p as well as HBEGF expression levels via real-time quantitative PCR (RT-qPCR). A Luciferase reporter assay was performed to detect the interaction between miR-98-5p and HBEGF gene. The serum levels of IL-2, TNF-α, TGF-β1 and IFN-γ in HCC patients and in the control group (healthy subjects) were measured by enzyme-linked immunosorbent assay (ELISA). In addition, receiver operator characteristic curve (ROC) was utilized to analyze the predictive ability of miR-98-5p combined with HBEGF for HCC. Finally, the survival curves were used to analyze the effect of HBEGF and miR-98-5p on the survival of patients with HCC.

RESULTS

RT-qPCR results showed that the expression level of miR-98-5p was significantly decreased, while HBEGF expression was significantly increased in the serum of HCC patients compared with the control group. Luciferase reporter assay confirmed that miR-98-5p could target and bind HBEGF. Additionally, according to ELISA, IL-2, TNF-α, and TGF-β1 were significantly increased, while IFN-γ was significantly decreased in the serum of HCC patients compared with the control group. The results of ROC indicated that expressive levels of miR-98-5p and HBEGF had a high diagnostic value for HCC. At the same time, the survival curve results indicated high HBEGF expression and low miR-98-5p expression, suggesting a poor prognosis for HCC patients.

CONCLUSION

MiR-98-5p can target the down-regulating HBEGF gene. In addition, miR-98-5p combined with MRI data is of crucial guiding value in assessing the prognosis of patients with HCC in the clinic.

Bioinformatic Deconstruction of Differentially Expressed Sequence Tags in Hepatocellular Carcinoma Based on Artificial Neural Network

Traditional medical imaging methods for diagnosing hepatocellular carcinoma can only provide information for differential diagnosis in terms of morphology and blood supply of the lesion, and the determination of the nature of the lesion still relies on tissue biopsy. Although ultrasound or CT-guided biopsy has become an effective method for the diagnosis of liver cancer in recent years, the puncture has the possibility of tumor irritation, liver tumor rupture, or needle tract metastasis. In this paper, the use of bioinformatics method is to gradually screen potentially high-risk genes associated with HCC recurrence on a genome-wide scale would help to discover the key target molecules. The ANN method was used to establish a gene prediction model that can predict the recurrence and survival of HCC, so as to construct a tool to identify patients at risk of HCC recurrence. It provided a certain therapeutic basis for future clinical work, thereby improving the prognosis of patients with HCC. Using the "survfit" function of the "survival" package in the R language, the log-rank test (the log-rank test was a common method for comparing two survival curves) was performed on all genes with posthoc recurrence of hepatocellular carcinoma as the outcome event. Then, the BLAST tool (Basic Local Alignment Search Tool) was used to search the similarity of each hepatocellular carcinoma database to find out the genes with similar sequences to each hepatocellular carcinoma, so as to determine the function of each differentially expressed sequence tag. This paper found that the AUC of the ANN model was greater than that of the discriminant analysis model (P < 0.05). This paper promoted the development of new therapeutic measures for hepatocellular carcinoma and provided important theoretical guidance for human beings to fight cancer.

miR-98-5p as a novel biomarker suppress liver fibrosis by targeting TGFβ receptor 1

BACKGROUND

Hepatic fibrosis is the repair reaction of excessive deposition and abnormal distribution of extracellular matrix after various liver injuries, especially chronic HBV infection, which is a key step in the development of various chronic liver diseases to cirrhosis. Recent studies have showed that microRNAs (miRNAs) can regulate a series of liver fibrosis-related gene express and play an important role in the development of liver fibrosis. But the miRNAs expression profiling and the differentially expressed miRNAs in patients with HBV-related liver fibrosis were little known. This study aims to have a record of a systemic screening for liver fibrosis-associated miRNAs in patients infected with HBV.

METHODS

A IlluminaHiSeq sequencing of plasma miRNAs from the HBV-related liver fibrosis patients (S2/3, n = 8) based on Scheuer's staging criteria and from healthy volunteers 42 (n = 7) was performed. Cluster analysis and target gene prediction were performed for the differentially expressed miRNAs. Gene ontology (GO) analysis and KEGG pathway enrichment analysis also were performed on the differentially expressed target miRNA genes.

RESULTS

Compared with the healthy control group, 77 miRNAs were screened out from the liver fibrosis group, among which 51 miRNAs were up-regulated and 26 miRNAs were down-regulated. Eventually, miR-98-5p was identified as a candidate predictor of liver fibrosis progression. miR-98-5p is reduced in activated LX2 cells, and miR-98-5p overexpression inhibited the HSCs activation. Mechanically, MiR-98-5p prevents liver fibrosis by targeting TGFbR1 and blocking TGFb1/Smad3 signaling pathway. Furthermore, serum miR-98-5p levels were measured from a total of 70 recruited patients with chronic HBV infection and 29 healthy individuals as controls. Serum miR-98-5p level was significantly lower in patients with liver fibrosis than in healthy controls and HBV carriers.

CONCLUSIONS

The expression of miRNAs in patients with liver fibrosis is significantly different from that of healthy volunteers. Many signal pathways of hepatic fibrosis are regulated by miRNAs. The potential value of miR-98-5p is as diagnostic biomarkers and therapeutic targets for HBV-related liver fibrosis.

PITPNA-AS1/miR-98-5p to Mediate the Cisplatin Resistance of Gastric Cancer

Gastric cancer (GC) is the most deadly gastrointestinal malignancy with high incidence and mortality. Although, molecular mechanisms which drive gastric cancer progression are extensively investigated, the roles of long noncoding RNA (lncRNA) in gastric cancer growth and drug sensitivity remain unclear. Platinum is a mainstay to treat gastric cancer, and platinum resistance always leads to the local recurrence of gastric cancer. Therefore, it is important to identify biomarkers or therapeutic targets to sensitize gastric cancer to platinum. In this study, we employ noncoding RNA sequencing and found that lncRNA PITPNA-AS1 is overexpressed in gastric cancer tissues and associated with poor survival of gastric cancer patients. Kockdown of PITPNA-AS1 in gastric cancer cells significantly inhibited cell growth and triggered apoptotic cell death in gastric cancer cells. Also, cisplatin treatment could decrease PITPNA-AS1 levels in gastric cancer cells through inhibiting H3K27ac. Besides, PITPNA-AS1 is elevated in cisplatin-resistant gastric cancer cells and tissues, PITPNA-AS1 knockdown could sensitize gastric cancer cells to cisplatin treatment. Furthermore, we identified that PITPNA-AS1 directly interacts and inhibits miR-98-5p. Therefore, PITPNA-AS1 could be served as a potential biomarkers and curative therapeutic targets for gastric cancer progression.

Long Non-coding RNA HOXA11-AS Facilitates Proliferation of Lung Adenocarcinoma Cells via Targeting the Let-7c-5p/IGF2BP1 Axis

Objective: This study investigates the relationship between the HOXA11-AS/let-7c-5p/IGF2BP1 regulatory axis and lung adenocarcinoma.

Methods: The expression levels of HOXA11-AS, let-7c-5p, and IGF2BP1 were evaluated in LUAD tissue and cell lines. Subcellular fractionation detection assay was adopted to verify the HOXA11-AS distribution in LUAD cells. The interaction relationship between let-7c-5p and HOXA11-AS or IGF2BP1 was validated by dual-luciferase reporter detection. In RNA binding protein immunoprecipitation assay, the binding relationship between HOXA11-AS and let-7c-5p was identified. The cell viability of transfected cells was tested by the Cell Counting Kit-8 assay. The mouse xenograft model was used to identify the effect of HOXA11-AS on tumor growth in vivo.

Results: Upregulation of lncRNA HOXA11-AS was found in LUAD, and suppression of HOXA11-AS could suppress the proliferative ability of LUAD cells. The let-7c-5p was expressed to be downregulated, which played an inhibitory role in LUAD cell proliferation. Let-7c-5p was negatively regulated by HOXA11-AS. HOXA11-AS promoted LUAD cell proliferation, while let-7c-5p had an inverse effect. Besides, IGF2BP1, regulated by let-7c-5p, had a positive relation with HOXA11-AS, while overexpression of IGF2BP1 could suppress the inhibition of silencing HOXA11-AS on LUAD cell proliferation. Experiments on mice confirmed that HOXA11-AS facilitated LUAD cell growth in vivo through regulating the let-7c-5p/IGF2BP1 axis.

Conclusion: HOXA11-AS promoted LUAD cell proliferation by targeting let-7c-5p/IGF2BP1, which could be potential molecular targets for LUAD.

Long non-coding RNA TMPO-AS1 facilitates the progression of colorectal cancer cells via sponging miR-98-5p to upregulate BCAT1 expression

BACKGROUND AND AIM

Colorectal cancer, as a common malignant carcinoma in the gastrointestinal tract, has a high mortality globally. However, the specific molecular mechanisms of long non-coding RNA (lncRNA) thymopoietin antisense transcript 1 (TMPO-AS1) in colorectal cancer were unclear.

METHODS

We tested the expression level of TMPO-AS1 via qRT-PCR in colorectal cancer cells, while the protein levels of branched chain amino acid transaminase 1 (BCAT1) and the stemness-related proteins were evaluated by western blot analysis. Colony formation, EdU staining, TUNEL, flow cytometry, and sphere formation assays were to assess the biological behaviors of colorectal cancer cells. Then, luciferase reporter, RIP, and RNA pull down assay were applied for confirming the combination between microRNA-98-5p (miR-98-5p) and TMPO-AS1/BCAT1.

RESULTS

TMPO-AS1 was aberrantly expressed at high levels in colorectal cancer cells. Silenced TMPO-AS1 restrained cell proliferation and stemness and promoted apoptosis oppositely, while overexpressing TMPO-AS1 exerted the adverse effects. Furthermore, miR-98-5p was proven to a target of TMPO-AS1 inhibit cell progression in colorectal cancer. Additionally, BCAT1 was proved to enhance cell progression as the target of miR-98-5p, and it offset the effect of silenced TMPO-AS1 on colorectal cancer cells.

CONCLUSION

TMPO-AS1 promotes the progression of colorectal cancer cells via sponging miR-98-5p to upregulate BCAT1 expression.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

3' UTR-truncated HMGA2 overexpression induces non-malignant in vivo expansion of hematopoietic stem cells in non-human primates

Vector-mediated mutagenesis remains a major safety concern for many gene therapy clinical protocols. Indeed, lentiviral-based gene therapy treatments of hematologic disease can result in oligoclonal blood reconstitution in the transduced cell graft. Specifically, clonal expansion of hematopoietic stem cells (HSCs) highly expressing HMGA2, a chromatin architectural factor found in many human cancers, is reported in patients undergoing gene therapy for hematologic diseases, raising concerns about the safety of these integrations. Here, we show for the first time in vivo multilineage and multiclonal expansion of non-human primate HSCs expressing a 3' UTR-truncated version of HMGA2 without evidence of any hematologic malignancy >7 years post-transplantation, which is significantly longer than most non-human gene therapy pre-clinical studies. This expansion is accompanied by an increase in HSC survival, cell cycle activation of downstream progenitors, and changes in gene expression led by the upregulation of IGF2BP2, a mRNA binding regulator of survival and proliferation. Thus, we conclude that prolonged ectopic expression of HMGA2 in hematopoietic progenitors is not sufficient to drive hematologic malignancy and is not an acute safety concern in lentiviral-based gene therapy clinical protocols.

ncRNAs-mediated high expression of SEMA3F correlates with poor prognosis and tumor immune infiltration of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is notorious for its poor prognosis. Increasing evidence has demonstrated that semaphorin 3F (SEMA3F) plays key roles in initiation and progression of several types of human cancer. However, the specific role and mechanism of SEMA3F in HCC remains not fully determined. In this study, we first performed pan-cancer analysis for SEMA3F's expression and prognosis using The Cancer Genome Atlas (TCGA) and The Genotype-Tissue Expression (GTEx) data and found that SEMA3F might be a potential oncogene in HCC. Subsequently, noncoding RNAs (ncRNAs) contributing to SEMA3F overexpression were identified by a combination of a series of in silico analyses, including expression analysis, correlation analysis, and survival analysis. Finally, the TMPO-AS1/SNHG16-let-7c-5p axis was identified as the most potential upstream ncRNA-related pathway of SEMA3F in HCC. Moreover, SEMA3F level was significantly positively associated with tumor immune cell infiltration, biomarkers of immune cells, and immune checkpoint expression. Collectively, our findings elucidated that ncRNAs-mediated upregulation of SEMA3F correlated with poor prognosis and tumor immune infiltration in HCC.

Comprehensive Analysis of Expression Regulation for RNA m6A Regulators With Clinical Significance in Human Cancers

Background

N6-methyladenosine (m6A), the most abundant chemical modification on eukaryotic messenger RNA (mRNA), is modulated by three class of regulators namely "writers," "erasers," and "readers." Increasing studies have shown that aberrant expression of m6A regulators plays broad roles in tumorigenesis and progression. However, it is largely unknown regarding the expression regulation for RNA m6A regulators in human cancers.

Results

Here we characterized the expression profiles of RNA m6A regulators in 13 cancer types with The Cancer Genome Atlas (TCGA) data. We showed that METTL14, FTO, and ALKBH5 were down-regulated in most cancers, whereas YTHDF1 and IGF2BP3 were up-regulated in 12 cancer types except for thyroid carcinoma (THCA). Survival analysis further revealed that low expression of several m6A regulators displayed longer overall survival times. Then, we analyzed microRNA (miRNA)-regulated and DNA methylation-regulated expression changes of m6A regulators in pan-cancer. In total, we identified 158 miRNAs and 58 DNA methylation probes (DMPs) involved in expression regulation for RNA m6A regulators. Furthermore, we assessed the survival significance of those regulatory pairs. Among them, 10 miRNAs and 7 DMPs may promote cancer initiation and progression; conversely, 3 miRNA/mRNA pairs in kidney renal clear cell carcinoma (KIRC) may exert tumor-suppressor function. These findings are indicative of their potential prognostic values. Finally, we validated two of those miRNA/mRNA pairs (hsa-miR-1307-3p/METTL14 and hsa-miR-204-5p/IGF2BP3) that could serve a critical role for potential clinical application in KIRC patients.

Conclusions

Our findings highlighted the importance of upstream regulation (miRNA and DNA methylation) governing m6A regulators' expression in pan-cancer. As a result, we identified several informative regulatory pairs for prognostic stratification. Thus, our study provides new insights into molecular mechanisms of m6A modification in human cancers.

MiR-590 Suppresses Proliferation and Induces Apoptosis in Pancreatic Cancer by Targeting High Mobility Group A2

BACKGROUND

Pancreatic ductal adenocarcinoma is a common malignancy with high morbidity. MicroRNAs have been demonstrated to be critical posttranscriptional regulators in tumorigenesis. This study aimed to investigate the effect of microRNA-590 on the proliferation and apoptosis of pancreatic ductal adenocarcinoma.

MATERIAL AND METHODS

The expression of microRNA-590 and high mobility group AT-hook 2 were examined in clinical pancreatic ductal adenocarcinoma tissues. Pancreatic ductal adenocarcinoma cell line Capan-2 was employed and transfected with microRNA-590 mimics or inhibitor. The correlation between microRNA-590 and high mobility group AT-hook 2 was verified by luciferase reporter assay. Cell viability and apoptosis were detected by MTT and flow cytometry assay. The protein level of high mobility group AT-hook 2, AKT, p-AKT, mTOR, and phosphorylated mTOR were analyzed by Western blotting.

RESULTS

MicroRNA-590 was found to be negatively correlated with the expression of high mobility group AT-hook 2 in pancreatic ductal adenocarcinoma tissues. Further studies identified high mobility group AT-hook 2 as a direct target of microRNA-590. Moreover, overexpression of microRNA-590 downregulated expression of high mobility group AT-hook 2, reduced cell viability, and promoted cell apoptosis, while knockdown of miR-590 led to an inverse result. MicroRNA-590 also suppressed the phosphorylation of AKT and mTOR without altering total AKT and mTOR levels.

CONCLUSION

Our study indicated that microRNA-590 negatively regulates the expression of high mobility group AT-hook 2 in clinical specimens and in vitro. MicroRNA-590 can inhibit cell proliferation and induce cell apoptosis in pancreatic ductal adenocarcinoma cells. This regulatory effect of microRNA-590 may be associated with AKT signaling pathway. Therefore, microRNA-590 has the potential to be used as a biomarker for predicting the progression of pancreatic ductal adenocarcinoma.

Ultrasound-Targeted Microbubble Destruction-Mediated miR-206 Overexpression Promotes Apoptosis and Inhibits Metastasis of Hepatocellular Carcinoma Cells Via Targeting PPIB

Background:

Ultrasound-targeted microbubble destruction (UTMD) has been found to be an effective method for delivering microRNAs (miRNAs, miRs). The current study is aimed at discovering the potential anti-cancer effects of UTMD-mediated miR-206 on HCC.

Methods:

In our study, the expressions of miR-206 and peptidyl-prolyl cis-trans isomerase B (PPIB) in HCC tissues and cells were detected by quantitative real-time polymerase chain reaction (qRT-PCR). PPIB expressions in HCC and adjacent normal tissues were analyzed by gene expression profiling interactive analysis (GEPIA). MiR-206 mimic and mimic control were transfected into HCC cells using UTMD. Potential binding sites between miR-206 and PPIB were predicted and confirmed by TargetScan and dual-luciferase reporter assay, respectively. Cell migration, invasion, and apoptosis were detected by wound healing assay, Transwell, and flow cytometry, respectively. The expressions of apoptosis-related proteins (Bax, Bcl-2), Epithelial-to-mesenchymal (EMT) markers (E-cadherin, N-cadherin and Snail) and PPIB were measured by Western blot.

Results:

MiR-206 expression was downregulated while PPIB expression was upregulated in HCC, and PPIB was recognized as a target gene of miR-206 in HCC tissues. UTMD-mediated miR-206 inhibited HCC cell migration and invasion while promoting apoptosis via regulating the expressions of proteins related to apoptosis, migration, and invasion by targeting PPIB.

Conclusion:

Our results suggested that the delivery of UTMD-mediated miR-206 could be a potential therapeutic method for HCC treatment, given its effects on inhibiting cell migration and invasion and promoting cell apoptosis.

MiR-98-5p promotes ischemia/reperfusion-induced microvascular dysfunction by targeting NGF and is a potential biomarker for microvascular reperfusion

OBJECTIVE

This study examined the correlation between serum miR-98-5p levels and indices of microvascular reperfusion in patients undergoing primary percutaneous coronary intervention (pPCI) after ST-segment elevation myocardial infarction (STEMI). Additionally, we evaluated the mechanisms by which miR-98-5p promoted ischemia/reperfusion (I/R)-induced injury in both cultured cell lines and an animal model.

METHODS

Circulating miR-98-5p levels were measured and compared from 171 STEMI patients undergoing pPCI, who were divided into two groups: no-reflow and reflow. The levels of miR-98-5p, nerve growth factor (NGF), and transient receptor potential vanilloid 1 (TRPV1) were analyzed in cultured human coronary endothelial cells (HCECs) exposed to hypoxia/reoxygenation (H/R). The effects of antagomir-98-5p on myocardial I/R-induced microvascular dysfunction in vivo were evaluated. Target gene expression and activity were assessed.

RESULTS

Higher miR-98-5p levels were associated with compromised indices of microvascular reperfusion. In vitro experiments on HCECs showed that exposure to H/R significantly increased miR-98-5p levels. We identified NGF as a novel target of miR-98-5p. Further, antagomir-98-5p relieved microvascular dysfunction and enhanced the expression of NGF and TRPV1 in the rat myocardial I/R model.

CONCLUSIONS

MiR-98-5p promotes microvascular dysfunction by targeting the NGF-TRPV1 axis. Serum miR-98-5p serves as a potential biomarker for microvascular reperfusion.

LncRNA HEIH Confers Cell Sorafenib Resistance in Hepatocellular Carcinoma by Regulating miR-98-5p/PI3K/AKT Pathway

Background

The hepatocellular carcinoma up-regulated EZH2-associated long non-coding RNA (HEIH) has been identified to act as an oncogene to promote cell tumorigenesis in hepatocellular carcinoma (HCC); however, the roles of HEIH in sorafenib resistance in HCC cells remain elusive.

Materials and Methods

The expression of HEIH and microRNA (miR)-98-5p was detected using quantitative real-time polymerase chain reaction. Cell viability, apoptosis, migration and invasion were analyzed using cell counting kit-8 assay, flow cytometry and transwell assay. Western blot was used to measure the levels of apoptosis-related protein and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway-related protein. The interaction between HEIH and miR-98-5p was confirmed by dual-luciferase reporter and RNA immunoprecipitation assay. In vivo experiments were performed using murine xenograft models.

Results

HEIH was up-regulated in sorafenib-resistant HCC tissues and cell lines, and HEIH silence weakened sorafenib resistance by suppressing cell viability, invasion and migration, decreasing the IC₅₀ values to sorafenib, and increasing apoptosis in sorafenib-resistant HCC cells in vitro and reinforced the anti-tumor effects of sorafenib in vivo. HEIH was a sponge of miR-98-5p, and miR-98-5p inhibition reversed the sorafenib sensitivity induced by HEIH deletion in sorafenib-resistant HCC cells. MiR-98-5p inhibition could activate PI3K/AKT pathway, and enhanced sorafenib resistance by regulating the activation of PI3K/AKT pathway in sorafenib-resistant HCC cells. Besides, HEIH also activated PI3K/AKT pathway through regulating miR-98-5p in sorafenib-resistant HCC cells.

Conclusion

HEIH conferred an advantage to sorafenib resistance in HCC by the activation of PI3K/AKT pathway through miR-98-5p, indicating a potential therapeutic strategy for HCC chemotherapy.

MicroRNA-98-5p Inhibits Tumorigenesis of Hepatitis B Virus-Related Hepatocellular Carcinoma by Targeting NF-κB-Inducing Kinase

PURPOSE

MicroRNAs play key regulatory roles in the tumorigenesis of hepatitis B virus-related hepatocellular carcinoma (HBV-HCC). This study aimed to explore the regulatory effects of microRNA-98-5p (miR-98-5p) on the proliferation, migration, invasion, and apoptosis of HBV-HCC cells, as well as the underlying mechanisms involving nuclear factor-κB-inducing kinase (NIK).

MATERIALS AND METHODS

The expressions of miR-98-5p and NIK in HBV-HCC tissues and cells, and the level of HBV DNA in HBV-HCC cells were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation, migration, invasion, and apoptosis of HBV-HCC cells were analyzed by cell counting kit-8, wound healing, transwell, and flow cytometry assay, respectively. The targeting relationship between miR-98-5p and NIK was predicted by StarBase3.0 and verified by dual-luciferase reporter assay. HBV-HCC xenograft tumor model was constructed in mice to observe the tumor growth in vivo.

RESULTS

The expression of miR-98-5p was declined in HBV-HCC tissues and cells. Overexpression of miR-98-5p markedly reduced the level of HBV DNA; inhibited the proliferation, migration, and invasion; and promoted the apoptosis of HBV-HCC cells. NIK was a target of miR-98-5p. Overexpression of miR-98-5p markedly decreased the protein expression of NIK in MHCC97H-HBV cells. NIK reversed the tumor-suppressing effect of miR-98-5p on HBV-HCC cells. Furthermore, overexpression of miR-98-5p significantly inhibited the xenograft tumor growth and decreased the expression of NIK in mice.

CONCLUSION

MiR-98-5p inhibits the secretion of HBV, proliferation, migration, and invasion of HBV-HCC cells by targeting NIK.

TMPO-AS1/miR-98-5p/EBF1 feedback loop contributes to the progression of bladder cancer

As reported in numerous studies, long non-coding RNAs (lncRNAs) exert significant effect on the regulation of tumor development. LncRNA TMPO antisense RNA 1 (TMPO-AS1) has been confirmed to be implicated in the development of several cancers. However, its clinical significance is still largely unknown in bladder cancer (BCa). In this study, high expression of TMPO-AS1 was revealed in BCa tissues and cell lines, and TMPO-AS1 predicted poor prognosis. Moreover, TMPO-AS1 facilitated cell growth. Additionally, TMPO-AS1 also boosted the migration and invasion of BCa cells. Mechanistically, overexpressed EBF transcription factor 1 (EBF1) in BCa cell was verified to promote the transcription of TMPO-AS1. Later, we found that TMPO-AS1 was a cytoplasmic RNA and could sponge miR-98-5p. Besides, it was validated that EBF1 is a target gene of miR-98-5p and negatively correlated with miR-98-5p in terms of expression level. According to the results of rescue experiments, we observed that EBF1 overexpression restored the repressive effect of TMPO-AS1 silencing on BCa development. Our research is the first to disclose the biological role and molecular mechanism of TMPO-AS1 in BCa, and TMPO-AS1 might be identified as a new therapeutic target for BCa patients.

miRNA-98-5p Targeting IGF2BP1 Induces Mesenchymal Stem Cell Apoptosis by Modulating PI3K/Akt and p53 in Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a common hematological autoimmune disease, in which defective mesenchymal stem cells (MSCs) are potentially involved. Our previous study suggested that MSCs in ITP patients displayed enhanced apoptosis. MicroRNAs (miRNAs) play important roles in ITP by affecting megakaryopoiesis, platelet production and immunoregulation, whereas the roles of miRNAs in ITP-MSCs remain unknown. In a previous study, we performed microarray analysis to obtain mRNA and miRNA profiles of ITP-MSCs. In the present study, we reanalyze the data and identify miR-98-5p as a candidate miRNA contributing to MSC deficiency in ITP. miR-98-5p acts through targeting insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1), and the subsequent downregulation of insulin-like growth factor 2 (IGF-2) causes inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, which is involved in the process of MSC deficiency. Furthermore, miR-98-5p upregulates p53 by inhibiting β-transducin repeat-containing protein (β-TrCP)-dependent p53 ubiquitination. Moreover, miR-98-5p overexpression impairs the therapeutic effect of MSCs in ITP mice. All-trans retinoic acid (ATRA) protects MSCs from apoptosis by downregulating miR-98-5p, thus providing a potential therapeutic approach for ITP. Our findings demonstrate that miR-98-5p is a critical regulator of ITP-MSCs, which will help us thoroughly understand the pathogenesis of ITP.

Circulating and tissue microRNAs as a potential diagnostic biomarker in patients with thrombotic events

Venous and arterial thrombosis are conditions that have a considerable burden if left untreated. The hypoxia-induced by the occluded vessel can disrupt the circulation of any organ, the cornerstone of treating thrombosis is rapid diagnosis and appropriate treatment. Diagnosis of thrombosis may be made by using laboratory tests or imaging techniques in individuals who have clinical manifestations of a thrombotic event. The use of serum micro ribonucleic acids (RNAs) has recently been applied to the diagnosis of thrombosis. These small RNA molecules are emerging as new diagnostic markers but have had very limited applications in vascular disease. Most of the articles provided various microRNAs with different levels of accuracy. However, there remains a lack of an appropriate panel of the most specific microRNA in the literature. The purpose of the present review was to summarize the existing data on the use of microRNAs as a diagnostic biomarker for venous thrombosis.

Interaction analysis of miR-1275/IGF2BP1/IGF2BP3 with the susceptibility to hepatocellular carcinoma

Aim: The aim of this study was to investigate the association of miR-1275 rs16759, IGF2BP1 rs11079850 and IGF2BP3 rs34414305 with hepatocellular carcinoma (HCC) risk. Materials & methods: Genotyping of the rs16759 and rs11079850 was performed using a Taqman assay and genotyping of the rs34414305 was performed using PCR. Relative expression of miR-1275, IGF2BP1 and IGF2BP3 was examined using quantitative PCR. Results: Comparison of the rs16759GG, CG/GG and CC genotype showed an increased risk of HCC. When comparing G with C allele, a significantly increased risk of HCC was also found. The rs16759, rs11079850 and rs34414305 had combined the interactive effects on the carcinogenesis of HCC. Moreover, the rs34414305 Del/ATT-Del/Del carriers displayed lower levels of IGF2BP3. Conclusion: The rs16759, rs11079850 and rs34414305 may singly and interactively contribute to carcinogenesis of HCC.

MicroRNA dysregulation interplay with childhood abdominal tumors

Abdominal tumors (AT) in children account for approximately 17% of all pediatric solid tumor cases, and frequently exhibit embryonal histological features that differentiate them from adult cancers. Current molecular approaches have greatly improved the understanding of the distinctive pathology of each tumor type and enabled the characterization of novel tumor biomarkers. As seen in abdominal adult tumors, microRNAs (miRNAs) have been increasingly implicated in either the initiation or progression of childhood cancer. Moreover, besides predicting patient prognosis, they represent valuable diagnostic tools that may also assist the surveillance of tumor behavior and treatment response, as well as the identification of the primary metastatic sites. Thus, the present study was undertaken to compile up-to-date information regarding the role of dysregulated miRNAs in the most common histological variants of AT, including neuroblastoma, nephroblastoma, hepatoblastoma, hepatocarcinoma, and adrenal tumors. Additionally, the clinical implications of dysregulated miRNAs as potential diagnostic tools or indicators of prognosis were evaluated.

MicroRNA-490-3p suppresses hepatocellular carcinoma cell proliferation and migration by targeting the aurora kinase A gene (AURKA)

INTRODUCTION

Hepatocellular carcinoma (HCC) is the most common and prevalent cancer type among liver cancers. In this study, expression of miR-490-3p and aurora kinase A gene (AURKA) was investigated in HCC. Additionally, we explored the microRNA (miR)-490-3p/AURKA relationship as well as the influence on HCC cell proliferation and migration.

MATERIAL AND METHODS

The dual luciferase reporter assay serves to verify the target relationship between miR-490-3p and AURKA. miR-490-3p mimics, AURKA siRNA and AURKA cDNA, were transfected into HCC cells. Quantitative real-time polymerase chain reaction and western blot were chosen for examining the relative expression of miR-490-3p and AURKA in HCC tissues, adjacent tissues, HCC cells and normal cells. The study detected the proliferation of HCC cells with the application of MTT assay and colony formation assay. Transwell assay was applied for the observation of migration, and wound healing assay for invasion.

RESULTS

The experiment results showed that miR-490-3p expression was down-regulated and AURKA expression was up-regulated in HCC cells and tissues. AURKA was the target gene of miR-490-3p and overexpression of miR-490-3p could inhibit the expression of AURKA in HCC cells. miR-490-3p overexpression could inhibit HCC cell migration and invasion, while AURKA promoted HCC cell migration. All experiment results indicated that miR-490-3p was low-expressed while AURKA was over-expressed in HCC cells and tissues compared to normal liver cells and tissues.

CONCLUSIONS

miR-490-3p could down-regulate the expression of AURKA, thus suppressing the proliferation and migration of HCC cells.

miR-98 Modulates Cytokine Production from Human PBMCs in Systemic Lupus Erythematosus by Targeting IL-6 mRNA

Objective

There is evidence that interleukin-6 (IL-6) upregulation plays a critical role in immunopathology of systemic lupus erythematosus (SLE). MicroRNA- (miRNA-) 98 was predicted to bind with the 3′-untranslated region (3′-UTR) of IL-6 gene. We hypothesized miR-98 through its regulation of IL-6 gene expression to influence cytokine production from peripheral blood mononuclear cells (PBMCs) in SLE.

Methods

The expression of miR-98 and IL-6 mRNA in the PBMCs of 41 SLE patients and 20 healthy controls (HC) was detected by quantitative reverse transcription PCR (qRT-PCR). The correlations between miR-98 expression and clinical features were evaluated. Luciferase reporter assay was performed to identify miR-98 targets. miR-98 mimics, miR-98 inhibitor, and IL-6 overexpression vector were generated. Cell viability of PBMCs was assessed using MTT assay. Gene expression and protein level were determined by qRT-PCR and Western blotting. TNF-α, IL-8, IL-1β, and IL-10 levels in cultured supernatants were quantified using ELISA.

Results

The expression of miR-98 was downregulated in PBMCs of SLE patients, and its expression is negatively associated with IL-6 levels. miR-98 expression was correlated with disease activity, lupus nephritis, and anti-dsDNA antibody. IL-6 mRNA was a target gene of miR-98. IL-6 overexpression promoted the proliferation of PBMCs and increased the levels of TNF-α, IL-8, IL-1β, and IL-10. Those effects were further enhanced by miR-98 inhibitor, while were suppressed by miR-98 mimics. miR-98 regulated the levels of STAT3 phosphorylation via its target gene IL-6.

Conclusion

The current study revealed that miR-98 could ameliorate STAT3-mediated cell proliferation and inflammatory cytokine production via its target gene IL-6 in patients with SLE. These results suggest that miR-98 might serve as a potential target for SLE treatment and other IL-6-mediated diseases.

Circulatory miR-98-5p levels are deregulated during diabetes and it inhibits proliferation and promotes apoptosis by targeting PPP1R15B in keratinocytes

Although deregulated circulatory miRNA signatures during diabetes have been identified for some years now, the effects of such miRNAs on several target tissues are not yet thoroughly investigated. The skin that is nourished by components present in the circulation exhibits several notable abnormal features during diabetes. We, therefore, hypothesized that such altered circulatory miRNA levels might be critical in the onset and progression of impaired skin health during diabetes. RNA sequencing from blood samples of normal and type 2 diabetic human subjects identified 9 upregulated and 19 downregulated miRNAs. miR-98-5p was significantly downregulated and its overexpression down-regulated PPP1R15B levels in HaCaT cells and this was prevented by the miR-98-5p inhibitor. This was validated in human primary epidermal keratinocytes and further supported by a dual reporter luciferase assay of the PPP1R15B 3'UTR where miR-98-5p significantly decreased the luciferase activity which was prevented in the presence of the miRNA inhibitor and by mutation in the miRNA binding site. By targeting PPP1R15B, miR-98-5p increases levels of p-eIF2α, BiP and CHOP. Consequently, there was induction of apoptosis accompanied with decreased proliferation in the presence of miR-98-5p. Conversely, miR-98-5p inhibition alone inhibited apoptosis and promoted proliferation. Taken together, our data suggest that by targeting PPP1R15B, miR-98-5p induces apoptosis and decreases proliferation. As opposed to this since circulatory miR-98-5p levels are decreased in diabetes, we believe that this decrease in the circulation that feeds the skin layers might be a major contributor of hyperproliferation as seen in the skin during diabetes.Abbreviations: miRNAs: MicroRNAs; PPP1R15B: PPP1R15B: Protein Phosphatase 1 Regulatory Subunit 15B; TGFβR1: Transforming Growth Factor Beta Receptor 1; ER: Endoplasmic Reticulum; Bip: Binding Immunoglobulin Protein; Chop: CCAAT-enhancer-binding protein homologous protein; p-eIF2α: Eukaryotic Translation Initiation Factor 2a; Bax: Bcl2-associated X protein; Bcl-2: B-cell CLL/lymphoma 2; PCNA: Proliferating Cell Nuclear Antigen; K5: Cytokeratin 5; qRT-PCR: Quantitative Real-Time PCR; ESCC: Oesophageal squamous cell carcinoma; HCC: Hepatocellular carcinoma; CTHRC1: Collagen triple helix repeat containing 1; SALL4: Sal-like protein 4; TNFα: Tumour Necrosis Factor alpha; PGC-1β: Peroxisome Profilerator-activated receptor-γ coactivator-1β; IGF2BP1: Insulin-like growth factor 2 mRNA binding protein 1.

MicroRNA-98-5p prevents bone regeneration by targeting high mobility group AT-Hook 2

MicroRNAs (mRNAs or miRs) serve an important role in the regulation of gene expression. In the present study, the role of miR-98-5p in bone regeneration was determined. Three osteoblast cell models were established, including primary human stem cells (BMMSC), mouse BMMSC's and MC3T3-E1 cells. miR-98-5p expression was determined using reverse transcription-quantitative (RT-q)PCR. Osteoblast markers, including alkaline phosphatase, runt related transcription factor 2 and transcription factor Sp7, were determined using RT-qPCR and western blot analysis, respectively. Alkaline phosphatase activity was determined in the present study and cell proliferation and apoptosis assays were performed. Furthermore, an association between miR-98-5p and high mobility group AT-Hook 2 (HMGA2) was revealed. This association was determined using TargetScan and a dual luciferase reporter assay. The current study demonstrated that miR-98-5p was downregulated during osteogenic differentiation and further demonstrated that HMGA2 may be a direct target of miR-98-5p. The results also demonstrated that miR-98-5p upregulation significantly inhibited the osteogenic differentiation of MC3T3-E1 cells, an effect that was reversed by an increased HMGA2 expression. Additionally, the results revealed that miR-98-5p upregulation inhibited MC3T3-E1 cell viability and induced cell apoptosis and these effects were eliminated by HMGA2 overexpression. In conclusion, miR-98-5p may prevent bone regeneration through inhibiting osteogenic differentiation and osteoblast growth by targeting HMGA2.

LncRNA THOR promotes tongue squamous cell carcinomas by stabilizing IGF2BP1 downstream targets

THOR, a highly conserved lncRNA, is potentially involved in various cancer development. However, its involvement in tongue squamous cell carcinoma (TSCC) remains unclear. The present study aims to explore the biological function and molecular mechanism of THOR in TSCC progression. The expressions of THOR and IGF2BP1 in TSCC tissues and adjacent non-cancerous tongue tissues (ANT) were examined through qRT-PCR. THOR levels were manipulated in TSCC cells to explore its function in cancer progression in vitro and in vivo, which were subsequently evaluated by CCK8, colony formation assay, flow cytometry, xenograft tumor assays. In situ hybridization, RIP and Western blot assay were performed to explore the underlying molecular mechanisms. We discovered that THOR and IGF2BP1 were dramatically upregulated in TSCC tissues. The expression of THOR is positively correlated with IGF2BP1 mRNA level. THOR mediated IGF2 expression via interacting with IGF2BP1, and affected the downstream MEK-ERK signaling pathway to regulate TSCC cells proliferation. THOR/IGF2BP1/IGF2-MEK-ERK axis regulated the proliferation of TSCC cells, implying that THOR would be a promising therapeutic target for TSCC patients.

miR-222 represses expression of zipcode binding protein-1 and phospholipase C-γ1 in intestinal epithelial cells

Both zipcode binding protein-1 (ZBP1) and phospholipase C-γ1 (PLCγ1) are intimately involved in many aspects of early intestinal mucosal repair after acute injury, but the exact mechanisms that control their cellular abundances remain largely unknown. The present study shows that microRNA-222 (miR-222) interacts with the mRNAs encoding ZBP1 and PLCγ1 and regulates ZBP1 and PLCγ1 expression in intestinal epithelial cells (IECs). The biotinylated miR-222 bound specifically to the ZBP1 and PLCγ1 mRNAs in IECs. Ectopically expressed miR-222 precursor destabilized the ZBP1 and PLCγ1 mRNAs and consequently lowered the levels of cellular ZBP1 and PLCγ1 proteins. Conversely, decreasing the levels of cellular miR-222 by transfection with its antagonism increased the stability of the ZBP1 and PLCγ1 mRNAs and increased the levels of ZBP1 and PLCγ1 proteins. Overexpression of miR-222 also inhibited cell migration over the wounded area, which was partially abolished by overexpressing ZBP1 and PLCγ1. Furthermore, prevention of the increased levels of ZBP1 and PLCγ1 in the miR-222-silenced cells by transfection with specific small interfering RNAs targeting ZBP1 or PLCγ1 mRNA inhibited cell migration after wounding. These findings indicate that induced miR-222 represses expression of ZBP1 and PLCγ1 at the posttranscriptional level, thus inhibiting IEC migration during intestinal epithelial restitution after wounding.

Drosophila Jak/STAT Signaling: Regulation and Relevance in Human Cancer and Metastasis

Over the past three-decades, Janus kinase (Jak) and signal transducer and activator of transcription (STAT) signaling has emerged as a paradigm to understand the involvement of signal transduction in development and disease pathology. At the molecular level, cytokines and interleukins steer Jak/STAT signaling to transcriptional regulation of target genes, which are involved in cell differentiation, migration, and proliferation. Jak/STAT signaling is involved in various types of blood cell disorders and cancers in humans, and its activation is associated with carcinomas that are more invasive or likely to become metastatic. Despite immense information regarding Jak/STAT regulation, the signaling network has numerous missing links, which is slowing the progress towards developing drug therapies. In mammals, many components act in this cascade, with substantial cross-talk with other signaling pathways. In Drosophila, there are fewer pathway components, which has enabled significant discoveries regarding well-conserved regulatory mechanisms. Work across species illustrates the relevance of these regulators in humans. In this review, we showcase fundamental Jak/STAT regulation mechanisms in blood cells, stem cells, and cell motility. We examine the functional relevance of key conserved regulators from Drosophila to human cancer stem cells and metastasis. Finally, we spotlight less characterized regulators of Drosophila Jak/STAT signaling, which stand as promising candidates to be investigated in cancer biology. These comparisons illustrate the value of using Drosophila as a model for uncovering the roles of Jak/STAT signaling and the molecular means by which the pathway is controlled.

Role of microRNAs in the main molecular pathways of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignant neoplasia. HCC is characterized by a poor prognosis. The need to find new molecular markers for its diagnosis and prognosis has led to a progressive increase in the number of scientific studies on this topic. MicroRNAs (miRNAs) are small non-coding RNA that play a role in almost all main cellular pathways. miRNAs are involved in the regulation of expression of the major tumor-related genes in carcinogenesis, acting as oncogenes or tumor suppressor genes. The aim of this review was to identify papers published in 2017 investigating the role of miRNAs in HCC tumorigenesis. miRNAs were classified according to their role in the main molecular pathways involved in HCC tumorigenesis: (1) mTOR; (2) Wnt; (3) JAK/STAT; (4) apoptosis; and (5) MAPK. The role of miRNAs in prognosis/response prediction was taken into consideration. Bearing in mind that the analysis of miRNAs in serum and other body fluids would be crucial for clinical management, the role of circulating miRNAs in HCC patients was also investigated. The most represented miRNA-regulated pathway in HCC is mTOR, but apoptosis, Wnt, JAK/STAT or MAPK pathways are also influenced by miRNA expression levels. These miRNAs could thus be used in clinical practice as diagnostic, prognostic or therapeutic targets for HCC treatment.

Downregulated miR-98-5p promotes PDAC proliferation and metastasis by reversely regulating MAP4K4

BACKGROUND

The aberrant expression of microRNAs (miRNAs) has emerged as important hallmarks of cancer. However, the molecular mechanisms underlying the differences of miRNA expression remain unclear. Many studies have reported that miR-98-5p plays vital functions in the development and progression of multiple cancers. However, its role in pancreatic ductal adenocarcinoma (PDAC) remains unknown.

METHODS

The expression of miR-98-5p and its specific target gene were determined in human PDAC specimens and cell lines by miRNA qRT-PCR, qRT-PCR and western blot. The effects of miR-98-5p depletion or ectopic expression on PDAC proliferation, migration and invasion were evaluated in vitro using CCK-8 proliferation assays, colony formation assays, wound healing assays and transwell assays. Furthermore, the in vivo effects were investigated using the mouse subcutaneous xenotransplantation and pancreatic tail xenotransplantation models. Luciferase reporter assays were employed to identify interactions between miR-98-5p and its specific target gene.

RESULTS

MiR-98-5p expression was significantly lower in cancerous tissues and associated with tumor size, TNM stage, lymph node metastasis and survival. Notably, a series of gain- and loss-of-function assays elucidated that miR-98-5p suppressed PDAC cell proliferation, migration and invasion both in vitro and in vivo. Luciferase reporter assays, western blot and qRT-PCR revealed MAP4K4 to be a direct target of miR-98-5p. The effects of ectopic miR-98-5p were rescued by MAP4K4 overexpression. In contrast, the effects of miR-98-5p depletion were impaired by MAP4K4 knockdown. Furthermore, miR-98-5p suppressed the MAPK/ERK signaling pathway through downregulation of MAP4K4. In addition, the expression level of miR-98-5p was negatively correlated with MAP4K4 expression in PDAC tissues and cell lines.

CONCLUSIONS

These results suggest that downregulation of miR-98-5p promotes tumor development by downregulation of MAP4K4 and inhibition of the downstream MAPK/ERK signaling, thus, highlighting the potential of miR-98-5p as a therapeutic target for PDAC.

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) in cancer

The insulin-like growth factor-2 mRNA-binding protein 1 (IGF2BP1) plays essential roles in embryogenesis and carcinogenesis. IGF2BP1 serves as a post-transcriptional fine-tuner regulating the expression of some essential mRNA targets required for the control of tumor cell proliferation and growth, invasion, and chemo-resistance, associating with a poor overall survival and metastasis in various types of human cancers. Therefore, IGF2BP1 has been traditionally regarded as an oncogene and potential therapeutic target for cancers. Nevertheless, a few studies have also demonstrated its tumor-suppressive role. However, the details about the contradictory functions of IGF2BP1 are unclear. The growing numbers of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been identified as its direct regulators, during tumor cell proliferation, growth, and invasion in multiple cancers. Thus, the mechanisms of post-transcriptional modulation of gene expression mediated by IGF2BP1, miRNAs, and lncRNAs in determining the fate of the development of tissues and organs, as well as tumorigenesis, need to be elucidated. In this review, we summarized the tissue distribution, expression, and roles of IGF2BP1 in embryogenesis and tumorigenesis, and focused on modulation of the interconnectivity between IGF2BP1 and its targeted mRNAs or non-coding RNAs (ncRNAs). The potential use of inhibitors of IGF2BP1 and its related pathways in cancer therapy was also discussed.

A Plasma Biomarker Panel of Four MicroRNAs for the Diagnosis of Prostate Cancer

Prostate cancer is diagnosed in over 1 million men every year globally, yet current diagnostic modalities are inadequate for identification of significant cancer and more reliable early diagnostic biomarkers are necessary for improved clinical management of prostate cancer patients. MicroRNAs (miRNAs) modulate important cellular processes/pathways contributing to cancer and are stably present in body fluids. In this study we profiled 372 cancer-associated miRNAs in plasma collected before (~60% patients) and after/during commencement of treatment (~40% patients), from age-matched prostate cancer patients and healthy controls, and observed elevated levels of 4 miRNAs - miR-4289, miR-326, miR-152-3p and miR-98-5p, which were validated in an independent cohort. The miRNA panel was able to differentiate between prostate cancer patients and controls (AUC = 0.88). Analysis of published miRNA transcriptomic data from clinical samples demonstrated low expression of miR-152-3p in tumour compared to adjacent non-malignant tissues. Overexpression of miR-152-3p increased proliferation and migration of prostate cancer cells, suggesting a role for this miRNA in prostate cancer pathogenesis, a concept that was supported by pathway analysis of predicted miR-152-3p target genes. In summary, a four miRNA panel, including miR-152-3p which likely targets genes with key roles in prostate cancer pathogenesis, has the potential to improve early prostate cancer diagnosis.

miR‑539 suppresses proliferation and induces apoptosis in renal cell carcinoma by targeting high mobility group A2

Renal cell carcinoma (RCC) is one of the most common urinary malignancies with a high rate of morbidity. MicroRNAs (miRNAs) have been shown to be critical post-transcriptional regulators in tumorigenesis. The present study aimed to investigate the effect of miRNA (miR)-539 on the proliferation and apoptosis of RCC. The expression of miR-539 and high mobility group AT-hook 2(HMGA2) were examined in clinical RCC specimens. The 786-O RCC cell line was also used and was transfected with miR-539 mimics or inhibitors. The correlation between miR-539 and HMGA2 was confirmed using a luciferase reporter assay. Cell viability and apoptosis were detected using MTT and flow cytometry assays. The protein levels of HMGA2, AKT, phosphorylated (p)-AKT, mammalian target of rapamycin (mTOR) and p-mTOR were analyzed using western blot analysis. The results revealed that miR-539 was negatively correlated with the expression of HMGA2 in clinical RCC specimens. Further experiments identified HMGA2 as a direct target of miR-539. The overexpression of miR-539 downregulated the expression of HMGA2, reduced cell proliferation and promoted cell apoptosis, whereas the knockdown of miR-539 led to the opposite results. miR-539 also suppressed the phosphorylation of AKT and mTOR, without altering the levels of total AKT and mTOR. Taken together, the results of the present study indicated that miR-539 negatively regulated the expression of HMGA2 in clinical specimens and in vitro. miR539 inhibited cell proliferation and induced apoptosis in RCC cells. This regulatory effect of miR-539 may be associated with the AKT signaling pathway. Therefore, miR-539 may be used as a biomarker for predicting the progression of RCC.