miR-221 silencing blocks hepatocellular carcinoma and promotes survival

Targeting non-coding RNAs and N6-methyladenosine modification in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most common form of primary liver cancers, accounts for a significant portion of cancer-related death globally. However, the molecular mechanisms driving the onset and progression of HCC are still not fully understood. Emerging evidence has indicated that non-protein-coding regions of genomes could give rise to transcripts, termed non-coding RNA (ncRNA), forming novel functional driving force for aberrant cellular activity. Over the past decades, overwhelming evidence has denoted involvement of a complex array of molecular function of ncRNAs at different stages of HCC tumorigenesis and progression. In this context, several pre-clinical studies have highlighted the potentials of ncRNAs as novel therapeutic modalities in the management of human HCC. Moreover, N6-methyladenosine (m6A) modification, the most prevalent form of internal mRNA modifications in mammalian cells, is essential for the governance of biological processes within cells. Dysregulation of m6A in ncRNAs has been implicated in human carcinogenesis, including HCC. In this review, we will discuss dysregulation of several hallmark ncRNAs (miRNAs, lncRNAs, and circRNAs) in HCC and address the latest advances for their involvement in the onset and progression of HCC. We also focus on dysregulation of m6A modification and various m6A regulators in the etiology of HCC. In the end, we discussed the contemporary preclinical and clinical application of ncRNA-based and m6A-targeted therapies in HCC.

Mechanisms of drug resistance in HCC

HCC comprises ∼80% of primary liver cancer. HCC is the only major cancer for which death rates have not improved over the last 10 years. Most patients are diagnosed with advanced disease when surgical and locoregional treatments are not feasible or effective. Sorafenib, a multikinase inhibitor targeting cell growth and angiogenesis, was approved for advanced unresectable HCC in 2007. Since then, other multikinase inhibitors have been approved. Lenvatinib was found to be noninferior to sorafenib as a first-line agent. Regorafenib, cabozantinib, and ramucirumab were shown to prolong survival as second-line agents. Advances in immunotherapy for HCC have also added hope for patients, but their efficacy remains limited. A large proportion of patients with advanced HCC gain no long-term benefit from systemic therapy due to primary and acquired drug resistance, which, combined with its rising incidence, keeps HCC a highly fatal disease. This review summarizes mechanisms of primary and acquired resistance to therapy and includes methods for bypassing resistance. It addresses recent advancements in immunotherapy, provides new perspectives on the linkage between drug resistance and molecular etiology of HCC, and evaluates the role of the microbiome in drug resistance. It also discusses alterations in signaling pathways, dysregulation of apoptosis, modulations in the tumor microenvironment, involvement of cancer stem cells, changes in drug metabolism/transport, tumor hypoxia, DNA repair, and the role of microRNAs in drug resistance. Understanding the interplay among these factors will provide guidance on the development of new therapeutic strategies capable of improving patient outcomes.

Predictive Role of Pretreatment Circulating miR-221 in Patients with Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization

Aberrantly expressed circulating microRNAs (miRNAs) have been demonstrated to have a crucial role in the diagnosis and prognostication of various cancers, including hepatocellular carcinoma (HCC). This research aimed to examine the role of specific miRNAs in predicting the outcomes for individuals with hepatitis B virus (HBV)-related HCC treated with transarterial chemoembolization (TACE). Stored serum specimens collected prior to the first TACE procedure were employed to determine the expression of serum miR-122, miR-221, and miR-224 using quantitative real-time PCR analysis. The study included 100 HCC patients (84% males, with an average age of 60 years) who were treated with TACE. Throughout the median follow-up spanning 18.5 months (within a range of 3 to 60 months), 42 (42.0%) patients met the criteria of TACE refractoriness. Through multivariate analysis, elevated expressed miR-221 (≥4.0 log10 copies) and advanced HCC staging were identified as independent factors related to TACE refractoriness and short overall survival. However, serum miR-122 and miR-224 levels were not linked to treatment response or overall survival. These findings underscored the potential of incorporating pretreatment levels of serum miR-221 into the established tumor staging to enhance the accurate assessment of TACE responsiveness and prognostic outcome of patients with HCC.

miR-221/222 induce instability of p53 By downregulating deubiquitinase YOD1 in acute myeloid leukemia

Acute myeloid leukemia (AML) is a hematological malignancy characterized by the impaired differentiation and uncontrolled proliferation of myeloid blasts. Tumor suppressor p53 is often downregulated in AML cells via ubiquitination-mediated degradation. While the role of E3 ligase MDM2 in p53 ubiquitination is well-accepted, little is known about the involvement of deubiquitinases (DUBs). Herein, we found that the expression of YOD1, among several DUBs, is substantially reduced in blood cells from AML patients. We identified that YOD1 deubiqutinated and stabilized p53 through interaction via N-terminus of p53 and OTU domain of YOD1. In addition, expression levels of YOD1 were suppressed by elevated miR-221/222 in AML cells through binding to the 3' untranslated region of YOD1, as verified by reporter gene assays. Treatment of cells with miR-221/222 mimics and inhibitors yielded the expected effects on YOD1 expressions, in agreement with the negative correlation observed between the expression levels of miR-221/222 and YOD1 in AML cells. Finally, overexpression of YOD1 stabilized p53, upregulated pro-apoptotic p53 downstream genes, and increased the sensitivity of AML cells to FLT3 inhibitors remarkably. Collectively, our study identified a pathway connecting miR-221/222, YOD1, and p53 in AML. Targeting miR-221/222 and stimulating YOD1 activity may improve the therapeutic effects of FLT3 inhibitors in patients with AML.

Therapeutic Targeting of Overexpressed MiRNAs in Cancer Progression

MicroRNAs (miRNAs) are non-coding RNAs involved in the modulation of various biological processes, and their dysregulation is greatly associated with cancer progression as miRNAs can act as either tumour suppressors or oncogenes, depending on their intended target, mechanism of actions, and expression levels. This review paper aims to shed light on the role of overexpressed miRNAs in cancer progression. Cancer cells are known to upregulate specific miRNAs to inhibit the expression of genes regulating the cell cycle, such as PTEN, FOXO1, SOX7, caspases, KLF4, TRIM8, and ZBTB4. Inhibition of these genes promotes cancer development and survival by inducing cell growth, migration, and invasion while evading apoptosis, which leads to poor cancer survival rates. Therefore, the potential of antisense miRNAs in treating cancer is also explored in this review. Antisense miRNAs are chemically modified oligonucleotides that can reverse the action of overexpressed miRNAs. Currently, the therapeutic potential of antisense miRNAs is being validated in both in vitro and in vivo models. Studies have shown that antisense miRNAs could slow down the progression of cancer while enhancing the action of conventional anticancer drugs. These findings provide hope for future oncologic care as this novel intervention is in the process of clinical translation.

miRNA therapeutics in precision oncology: a natural premium to nurture

The dynamic spectrum of microRNA (miRNA) has grown significantly over the years with its identification and exploration in cancer therapeutics and is currently identified as an important resource for innovative strategies due to its functional behavior for gene regulation and modulation of complex biological networks. The progression of cancer is the consequence of uncontrolled, nonsynchronous procedural faults in the biological system. Diversified and variable cellular response of cancerous cells has always raised challenges in effective cancer therapy. miRNAs, a class of non-coding RNAs (ncRNAs), are the natural genetic gift, responsible to preserve the homeostasis of cell to nurture. The unprecedented significance of endogenous miRNAs has exhibited promising therapeutic potential in cancer therapeutics. Currently, miRNA mimic miR-34, and an antimiR aimed against miR-122 has entered the clinical trials for cancer treatments. This review, highlights the recent breakthroughs, challenges, clinical trials, and advanced delivery vehicles in the administration of miRNA therapies for precision oncology.

CKAP2L, a crucial target of miR-326, promotes prostate cancer progression

Background

The overexpression of aberrant cell cycle signaling pathway associated protein has been implicated in multiple malignancies and the identification of all-important one among is the crux of the precise targeted therapy. CKAP2L (Cytoskeleton Associated Protein 2 Like) plays a newish role in cancer progression through activation of the process of cell cycle and mitosis. In this study, we aim to delineate the prominent dysregulated expression of CKAP2L and comprehensively reveal its deregulation in prostate cancer. 

Method

CKAP2L expression was examined in the normal and tumor tissues of prostate cancer patients with RT-QPCR and Western blot. IHC showed the different expression in normal prostate tissue, tissue of BPH, low Gleason Score and high Gleason Score prostate cancer patients. Transwell, colony formation, MTT and flow cytometry were performed to detected the changes in cellular function in vitro. The xenograft model was conducted for the changes in vivo. Dual luciferase and RIP proved the binding relation between CKAP2L and miR-326.

Results

In multiple datasets, CKAP2L was found upregulated and positively associated with Gleason grade and poor clinical outcomes of patients. shRNA mediated silence of CKAP2L suppressed cell proliferation, impaired monolayer formation, inhibited cell invasion. CKAP2L was confirmed to be the direct target of miR-326, which had a carcinostatic effect by binding the 3’untranslated regions (3’UTRs) of CKAP2L mRNA. The deletion of CKAP2L resulted in reduced expression of genes involved in the mitotic cell cycle such as multiple cyclin-dependent kinases and cyclins, but also several genes encoding proteins involved in chromosome segregation and spindle assembly.

Conclusion

Taken together, CKAP2L plays a carcinogenic role in prostate cancer by regulates the expression of cycle-associated proteins.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09762-3.

miR-221/222 as biomarkers and targets for therapeutic intervention on cancer and other diseases: A systematic review

Among deregulated microRNAs (miRs) in human malignancies, miR-221 has been widely investigated for its oncogenic role and as a promising biomarker. Moreover, recent evidence suggests miR-221 as a fine-tuner of chronic liver injury and inflammation-related events. Available information also supports the potential of miR-221 silencing as promising therapeutic intervention. In this systematic review, we selected papers from the principal databases (PubMed, MedLine, Medscape, ASCO, ESMO) between January 2012 and December 2020, using the keywords “miR-221” and the specific keywords related to the most important hematologic and solid malignancies, and some non-malignant diseases, to define and characterize deregulated miR-221 as a valuable therapeutic target in the modern vision of molecular medicine. We found a major role of miR-221 in this view.

MiR-363-3p/S1PR1 axis inhibits sepsis-induced acute lung injury via the inactivation of NF-κB signaling

Infection-associated inflammation and coagulation are critical pathologies in sepsis-induced acute lung injury (ALI). This study aimed to investigate the effects of microRNA-363-3p (miR-363-3p) on sepsis-induced ALI and explore the underlying mechanisms. A cecal ligation and puncture-induced septic mouse model was established. The results of this study suggested that miR-363-3p was highly expressed in lung tissues of septic mice. Knockdown of miR-363-3p attenuated sepsis-induced histopathological damage, the inflammation response and oxidative stress in lung tissues. Furthermore, knockdown of miR-363-3p reduced the formation of platelet-derived microparticles and thrombin generation in blood samples of septic mice. Downregulation of miR-363-3p suppressed sphingosine-1-phosphate receptor 1 (S1PR1) expression in lung tissues and subsequently inactivated the nuclear factor kappa-B ligand (NF-κB) signaling. A luciferase reporter assay confirmed that miR-363-3p directly targeted the 3'-UTR of the mouse S1pr1 mRNA. Collectively, our study suggests that inactivation of NF-κB signaling is involved in the miR-363-3p/S1PR1 axis-mediated protective effect on septic ALI.

Delivery of Anti-miRNA-221 for Colorectal Carcinoma Therapy Using Modified Cord Blood Mesenchymal Stem Cells-Derived Exosomes

Background: Exosomes, as natural intercellular information carriers, have great potential in the field of drug delivery. Many studies have focused on modifying exosome surface proteins to allow drugs to specifically target cancer cells.

Methods: In this study, human cord blood mesenchymal stromal cell-derived exosomes were used in the delivery of anti-miRNA oligonucleotides so as to be specifically ingested by tumor cells to perform anti-tumor functions. Mesenchymal stem cells modified by the fusion gene iRGD-Lamp2b were constructed to separate and purify exosomes, and the anti-miRNA-221 oligonucleotide (AMO) was loaded into the exosomes by electroporation.

Results: The AMO-loaded exosomes (AMO-Exos) effectively inhibited the proliferation and clonal formation of colon cancer cells in vitro, and it was further found that AMO-Exos was taken up by tumor cells through interaction with the NRP-1 protein. The results of a xenograft tumor model also showed that iRGD-modified exosomes were obviously enriched in tumor sites, exerting excellent anti-tumor efficacy. In vivo imaging showed that exosomes were mainly distributed in liver, spleen, and lung tissues.

Conclusion: Our results suggest that genetically modified exosomes could be an ideal natural nanostructure for anti-miRNA oligonucleotide delivery.

Risk Factors and Prevention of Viral Hepatitis-Related Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common cancer in the world, and its incidence is increasing yearly. Hepatitis B virus (HBV) infection and hepatitis C virus (HCV) infection are important causes of HCC. Liver cirrhosis, age, sex, smoking and drinking, and metabolic risk factors will increase the risk of cancer in HBV/HCV patients. And viral load, APRI, FIB-4, and liver stiffness can all predict the risk of HCC in patients with viral infection. In addition, effective prevention strategies are essential in reducing the risk of HCC. The prevention of HCC involves mainly tertiary prevention strategies, while the primary prevention is based on standardized vaccine injections to prevent the occurrence of HBV/HCV. Eliminating the route of transmission and vaccination will lead to a decrease in the incidence of HCC. Secondary prevention involves effective antiviral treatment of HBV/HCV to prevent the disease from progressing to HCC, and tertiary prevention is actively treating HCC to prevent its recurrence.

Epigenetic Changes Affecting the Development of Hepatocellular Carcinoma

Simple Summary

Hepatocellular carcinoma is a life-threatening disease. Despite many efforts to understand the exact pathogenesis and the signaling pathways involved in its formation, treatment remains unsatisfactory. Currently, an important function in the development of neoplastic diseases and treatment effects is attributed to changes taking place at the epigenetic level. Epigenetic studies revealed modified methylation patterns in HCC, dysfunction of enzymes engaged in the DNA methylation process, the aberrant function of non-coding RNAs, and a set of histone modifications that influence gene expression. The aim of this review is to summarize the current knowledge on the role of epigenetics in the formation of hepatocellular carcinoma.

Abstract

Hepatocellular carcinoma (HCC) remains a serious oncologic issue with still a dismal prognosis. So far, no key molecular mechanism that underlies its pathogenesis has been identified. Recently, by specific molecular approaches, many genetic and epigenetic changes arising during HCC pathogenesis were detected. Epigenetic studies revealed modified methylation patterns in HCC tumors, dysfunction of enzymes engaged in the DNA methylation process, and a set of histone modifications that influence gene expression. HCC cells are also influenced by the disrupted function of non-coding RNAs, such as micro RNAs and long non-coding RNAs. Moreover, a role of liver cancer stem cells in HCC development is becoming evident. The reversibility of epigenetic changes offers the possibility of influencing them and regulating their undesirable effects. All these data can be used not only to identify new therapeutic targets but also to predict treatment response. This review focuses on epigenetic changes in hepatocellular carcinoma and their possible implications in HCC therapy.

The Role of miRNA in the Pathophysiology of Neuroendocrine Tumors

Neuroendocrine tumors (NETs) represent a tumor group that is both rare and heterogeneous. Prognosis is largely determined by the tumor grading and the site of the primary tumor and metastases. Despite intensive research efforts, only modest advances in diagnostic and therapeutic approaches have been achieved in recent years. For patients with non-respectable tumor stages, prognosis is poor. In this context, the development of novel diagnostic tools for early detection of NETs and prediction of tumor response to therapy as well as estimation of the overall prognosis would greatly improve the clinical management of NETs. However, identification of novel diagnostic molecules is hampered by an inadequate understanding of the pathophysiology of neuroendocrine malignancies. It has recently been demonstrated that microRNA (miRNA), a family of small RNA molecules with an established role in the pathophysiology of quite different cancer entities, may also play a role as a biomarker. Here, we summarize the available knowledge on the role of miRNAs in the development of NET and highlight their potential use as serum-based biomarkers in the context of this disease. We discuss important challenges currently preventing their use in clinical routine and give an outlook on future directions of miRNA research in NET.

Transcription Factors and Methylation Drive Prognostic miRNA Dysregulation in Hepatocellular Carcinoma

Many dysregulated microRNAs (miRNAs) have been suggested to serve as oncogenes or tumor suppressors to act as diagnostic and prognostic factors for HCC patients. However, the dysregulated mechanisms of miRNAs in HCC remain largely unknown. Herein, we firstly identify 114 disordered mature miRNAs in HCC, 93 of them are caused by dysregulated transcription factors, and 10 of them are driven by the DNA methylation of their promoter regions. Secondly, we find that seven up-regulated miRNAs (miR-9-5p, miR-452-5p, miR-452-3p, miR-1180-3p, miR-4746-5p, miR-3677-3 and miR-4661-5p) can promote tumorigenesis via inhibiting multiple tumor suppressor genes participated in metabolism, which may act as oncogenes, and seven down-regulated miRNAs (miR-99-5p, miR-5589-5p, miR-5589-3p, miR-139-5p, miR-139-3p, miR-101-3p and miR-125b-5p) can suppress abnormal cell proliferation via suppressing a number of oncogenes involved in cancer-related pathways, which may serve as tumor suppressors. Thirdly, our findings reveal a mechanism that transcription factor and miRNA interplay can form various regulatory loops to synergistically control the occurrence and development of HCC. Finally, our results demonstrate that this key transcription factor FOXO1 can activate a certain number of tumor suppressor miRNAs to improve the survival of HCC patients, suggesting FOXO1 as an effective therapeutic target for HCC patients. Overall, our study not only reveals the dysregulated mechanisms of miRNAs in HCC, but provides several novel prognostic biomarkers and potential therapeutic targets for HCC patients.

Therapeutic strategies for miRNA delivery to reduce hepatocellular carcinoma

Malignancies of hepatocellular carcinoma (HCC) are rapidly spreading and commonly fatal. Like most cancers, the gene expression patterns in HCC vary significantly from patient to patient. Moreover, the expression networks during HCC progression are largely controlled by microRNAs (miRNAs) regulating multiple oncogenes and tumor supressors. Therefore, miRNA-based therapeutic strategies altering these networks may significantly influence the cellular behavior enough for them to cure HCC. However, the most substantial challenges in developing such therapies are the stability of the oligos themselves and that of their delivery systems. Here we provide a comprehensive update describing various miRNA delivery systems, including virus-based delivery and non-viral delivery. The latter may be achieved using inorganic nanoparticles, polymer based nano-carriers, lipid-based vesicles, exosomes, and liposomes. Leaky vasculature in HCC-afflicted livers helps untargeted nanocarriers to accumulate in the tumor tissue but may result in side effects during higher dose of treatment. On the other hand, the strategies for actively targeting miRNA therepeutics to cancerous cells through nano-conjugates or vesicles by decorating their surface with antibodies against or ligands for HCC-specific antigens or receptors are more efficient in preventing damage to healthy tissue and cancer recurrence.

HAND2-AS1: A functional cancer-related long non-coding RNA

Long non-coding RNAs (lncRNAs) regulate gene expression and carcinogenesis. The lncRNA heart and neural crest derivatives expressed transcript 2 antisense RNA 1 (HAND2‑AS1) suppresses tumor growth, and its expression level was lower in tumor tissues than in adjacent normal tissues of most types of human cancers, including non-small cell lung cancer, ovarian cancer, breast cancer, gastric cancer, colorectal cancer, cervical cancer, endometrial cancer, prostate cancer, and esophagus squamous cell carcinoma. However, one study reported that the HAND2‑AS1 expression was upregulated in hepatocellular carcinoma tissues comparing with non-tumor tissues and it promoted tumor development. The aberrant expression of HAND2-AS1 was strongly linked to tumor progression and prognosis. Moreover, HAND2-AS1 was involved in tumor cell proliferation, differentiation, apoptosis, and cellular glucose metabolism. This review summarizes data on the expression profile, functions, underlying mechanism, and clinical value of HAND2-AS1 in cancer. The expression profile of HAND2-AS1 in 33 tumors was evaluated by bioinformatics analysis of The Cancer Genome Atlas.

Epigenetic mechanisms in hepatitis B virus-associated hepatocellular carcinoma

Chronic infection of the liver by the hepatitis B virus (HBV) is associated with increased risk for developing hepatocellular carcinoma (HCC). A multitude of studies have investigated the mechanism of liver cancer pathogenesis due to chronic HBV infection. Chronic inflammation, expression of specific viral proteins such as HBx, the integration site of the viral genome into the host genome, and the viral genotype, are key players contributing to HCC pathogenesis. In addition, the genetic background of the host and exposure to environmental carcinogens are also predisposing parameters in hepatocarcinogenesis. Despite the plethora of studies, the molecular mechanism of HCC pathogenesis remains incompletely understood. In this review, the focus is on epigenetic mechanisms involved in the pathogenesis of HBV-associated HCC. Epigenetic mechanisms are dynamic molecular processes that regulate gene expression without altering the host DNA, acting by modifying the host chromatin structure via covalent post-translational histone modifications, changing the DNA methylation status, expression of non-coding RNAs such as microRNAs and long noncoding RNAs, and altering the spatial, 3-D organization of the chromatin of the virus-infected cell. Herein, studies are described that provide evidence in support of deregulation of epigenetic mechanisms in the HBV-infected/-replicating hepatocyte and their contribution to hepatocyte transformation. In contrast to genetic mutations which are permanent, epigenetic alterations are dynamic and reversible. Accordingly, the identification of essential molecular epigenetic targets involved in HBV-mediated HCC pathogenesis offers the opportunity for the design and development of novel epigenetic therapeutic approaches.

MicroRNAs in the Pathogenesis of Hepatocellular Carcinoma: A Review

Simple Summary

Hepatocellular carcinoma (HCC) is one of the most frequently occurring cancers, and the prognosis for late-stage HCC remains poor. A better understanding of the pathogenesis of HCC is expected to improve outcomes. MicroRNAs (miRNAs) are small, noncoding, single-stranded RNAs that regulate the expression of various target genes, including those in cancer-associated genomic regions or fragile sites in various human cancers. We summarize the central roles of miRNAs in the pathogenesis of HCC and discuss their potential utility as valuable biomarkers and new therapeutic agents for HCC.

Abstract

Hepatocellular carcinoma (HCC) is the seventh most frequent cancer and the fourth leading cause of cancer mortality worldwide. Despite substantial advances in therapeutic strategies, the prognosis of late-stage HCC remains dismal because of the high recurrence rate. A better understanding of the etiology of HCC is therefore necessary to improve outcomes. MicroRNAs (miRNAs) are small, endogenous, noncoding, single-stranded RNAs that modulate the expression of their target genes at the posttranscriptional and translational levels. Aberrant expression of miRNAs has frequently been detected in cancer-associated genomic regions or fragile sites in various human cancers and has been observed in both HCC cells and tissues. The precise patterns of aberrant miRNA expression differ depending on disease etiology, including various causes of hepatocarcinogenesis, such as viral hepatitis, alcoholic liver disease, or nonalcoholic steatohepatitis. However, little is known about the underlying mechanisms and the association of miRNAs with the pathogenesis of HCC of various etiologies. In the present review, we summarize the key mechanisms of miRNAs in the pathogenesis of HCC and emphasize their potential utility as valuable diagnostic and prognostic biomarkers, as well as innovative therapeutic targets, in HCC diagnosis and treatment.

Beyond regulations at DNA levels: A review of epigenetic therapeutics targeting cancer stem cells

In the past few years, the paramount role of cancer stem cells (CSCs), in terms of cancer initiation, proliferation, metastasis, invasion and chemoresistance, has been revealed by accumulating studies. However, this level of cellular plasticity cannot be entirely explained by genetic mutations. Research on epigenetic modifications as a complementary explanation for the properties of CSCs has been increasing over the past several years. Notably, therapeutic strategies are currently being developed in an effort to reverse aberrant epigenetic alterations using specific chemical inhibitors. In this review, we summarize the current understanding of CSCs and their role in cancer progression, and provide an overview of epigenetic alterations seen in CSCs. Importantly, we focus on primary cancer therapies that target the epigenetic modification of CSCs by the use of specific chemical inhibitors, such as histone deacetylase (HDAC) inhibitors, DNA methyltransferase (DNMT) inhibitors and microRNA‐based (miRNA‐based) therapeutics.

Molecular and Functional Roles of MicroRNAs in the Progression of Hepatocellular Carcinoma-A Review

Liver cancer is the fourth leading cause of cancer deaths globally, of which hepatocellular carcinoma (HCC) is the major subtype. Viral hepatitis B and C infections, alcohol abuse, and metabolic disorders are multiple risk factors for liver cirrhosis and HCC development. Although great therapeutic advances have been made in recent decades, the prognosis for HCC patients remains poor due to late diagnosis, chemotherapy failure, and frequent recurrence. MicroRNAs (miRNAs) are endogenous, non-coding RNAs that regulate various molecular biological phenomena by suppressing the translation of target messenger RNAs (mRNAs). miRNAs, which often become dysregulated in malignancy, control cell proliferation, migration, invasion, and development in HCC by promoting or suppressing tumors. Exploring the detailed mechanisms underlying miRNA-mediated HCC development and progression can likely improve the outcomes of patients with HCC. This review summarizes the molecular and functional roles of miRNAs in the pathogenesis of HCC. Further, it elucidates the utility of miRNAs as novel biomarkers and therapeutic targets.

Upregulation of miR-124-3p by Liver X Receptor Inhibits the Growth of Hepatocellular Carcinoma Cells Via Suppressing Cyclin D1 and CDK6

MiR-124-3p has been identified as a novel tumor suppressor and a potential therapeutic target in hepatocellular carcinoma (HCC) through regulating its target genes. However, the upstream regulatory mechanisms of mir-124-3p in HCC has not been fully understood. The transcription factor liver X receptor (LXR) plays a critical role in suppressing the proliferation of HCC cells, but it is unclear whether LXR is involved in the regulation of mir-124-3p. In the present study, we demonstrated that the expression of mir-124-3p was positively correlated with that of LXR in HCC, and the cell growth of HCC was significantly inhibited by LXR agonists. Moreover, activation of LXR with the agonists up-regulated the expression of mir-124-3p, and in turn down-regulated cyclin D1 and cyclin-dependent kinase 6 (CDK6) expression, which are the target genes of mir-124-3p. Mechanistically, miR-124-3p mediates LXR induced inhibition of HCC cell growth and down-regulation of cyclin D1 and CDK6 expression. In vivo experiments also confirmed that LXR induced miR-124-3p expression inhibited the growth of HCC xenograft tumors, as well as cyclin D1 and CDK6 expression. Our findings revealed that miR-124-3p is a novel target gene of LXR, and regulation of the miR-124-3p-cyclin D1/CDK6 pathway by LXR plays a crucial role in the proliferation of HCC cells. LXR-miR-124-3p-cyclin D1/CDK6 pathway may be a novel potential therapeutic target for HCC treatment.

Participation of MicroRNAs in the Treatment of Cancer with Phytochemicals

Cancer is a global health concern and one of the main causes of disease-related death. Even with considerable progress in investigations on cancer therapy, effective anti-cancer agents and regimens have thus far been insufficient. There has been compelling evidence that natural phytochemicals and their derivatives have potent anti-cancer activities. Plant-based anti-cancer agents, such as etoposide, irinotecan, paclitaxel, and vincristine, are currently being applied in medical treatments for patients with cancer. Further, the efficacy of plenty of phytochemicals has been evaluated to discover a promising candidate for cancer therapy. For developing more effective cancer therapy, it is required to apprehend the molecular mechanism deployed by natural compounds. MicroRNAs (miRNAs) have been realized to play a pivotal role in regulating cellular signaling pathways, affecting the efficacy of therapeutic agents in cancer. This review presents a feature of phytochemicals with anti-cancer activity, focusing mainly on the relationship between phytochemicals and miRNAs, with insights into the role of miRNAs as the mediators and the regulators of anti-cancer effects of phytochemicals.

Restoration of RNA helicase DDX5 suppresses hepatitis B virus (HBV) biosynthesis and Wnt signaling in HBV-related hepatocellular carcinoma

Rationale: RNA helicase DDX5 is downregulated during hepatitis B virus (HBV) replication, and poor prognosis HBV-related hepatocellular carcinoma (HCC). The aim of this study is to determine the mechanism and significance of DDX5 downregulation for HBV-driven HCC, and identify biologics to prevent DDX5 downregulation. Methods: Molecular approaches including immunoblotting, qRT-PCR, luciferase transfections, hepatosphere assays, Assay for Transposase-Accessible Chromatin sequencing (ATAC-seq), and RNA-seq were used with cellular models of HBV replication, HBV infection, and HBV-related liver tumors, as well as bioinformatic analyses of liver cancer cells from two independent cohorts. Results: We demonstrate that HBV infection induces expression of the proto-oncogenic miR17~92 and miR106b~25 clusters which target the downregulation of DDX5. Increased expression of these miRNAs is also detected in HBV-driven HCCs exhibiting reduced DDX5 mRNA. Stable DDX5 knockdown (DDX5^KD) in HBV replicating hepatocytes increased viral replication, and resulted in hepatosphere formation, drug resistance, Wnt activation, and pluripotency gene expression. ATAC-seq of DDX5^KD compared to DDX5 wild-type (WT) cells identified accessible chromatin regions enriched in regulation of Wnt signaling genes. RNA-seq analysis comparing WT versus DDX5^KD cells identified enhanced expression of multiple genes involved in Wnt pathway. Additionally, expression of Disheveled, DVL1, a key regulator of Wnt pathway activation, was significantly higher in liver cancer cells with low DDX5 expression, from two independent cohorts. Importantly, inhibitors (antagomirs) to miR17~92 and miR106b~25 restored DDX5 levels, reduced DVL1 expression, and suppressed both Wnt activation and viral replication. Conclusion : DDX5 is a negative regulator of Wnt signaling and hepatocyte reprogramming in HCCs. Restoration of DDX5 levels by miR17~92 / miR106b~25 antagomirs in HBV-infected patients can be explored as both antitumor and antiviral strategy.

Recent Progress on Relevant microRNAs in Autism Spectrum Disorders

Autism spectrum disorder (ASD) is a neurodevelopmental disorder whose pathogenesis is unclear and is affected by both genetic and environmental factors. The microRNAs (miRNAs) are a kind of single-stranded non-coding RNA with 20-22 nucleotides, which normally inhibit their target mRNAs at a post-transcriptional level. miRNAs are involved in almost all biological processes and are closely related to ASD and many other diseases. In this review, we summarize relevant miRNAs in ASD, and analyze dysregulated miRNAs in brain tissues and body fluids of ASD patients, which may contribute to the pathogenesis and diagnosis of ASD.

HBV infection exacerbates PTEN defects in hepatocellular carcinoma through upregulation of miR-181a/382/362/19a

A high hepatitis B virus (HBV) load and chronic hepatitis B infection are well-recognized risk factors for the development of hepatocellular carcinoma (HCC), highlighting the need for research into the mechanisms underlying the role of HBV infection in HCC. Because phosphatase and tensin homolog (PTEN) has been implicated in HCC development, we explored whether PTEN has a role in HBV-related hepatocarcinogenesis. We found that PTEN expression was correlated with advanced clinicopathological features and that HBV infection exacerbates PTEN defects in HCC. Using an integrated approach, we then investigated if miRNAs linked HBV infection to PTEN downregulation in HCC and found that PTEN was a target of miR-181a/382/362/19a. We also show that miR-181a/382/362/19a-mediated inhibition of PTEN led to an enhanced malignant phenotype and stimulation of AKT signaling in HCC cells. Collectively, our results indicate that HBV infection exacerbates PTEN defects in hepatocellular carcinoma through upregulation of miR-181a/362/382/19a. Our work implicates miR-181a/362/382/19a and PTEN as potential biomarkers and targets for novel prognostic, diagnostic, and therapeutic strategies targeting HBV-related HCC.

A Licorice Roots Extract Induces Apoptosis and Cell Cycle Arrest and Improves Metabolism via Regulating MiRNAs in Liver Cancer Cells

Targeting altered metabolism in cancer provides a promising preventive and therapeutic approach. Natural products interplay between gene expression and metabolism either by targeting altered metabolic enzymes and/or affecting the regulating miRNAs. Licorice is a widely known product used as flavoring agent. Glycyrrhizin and other metabolites were reported to exert several metabolic benefits. Here, we investigated the effect of licorice roots extract on some metabolic pathways and their regulating miRNAs in hepatocellular carcinoma cells. Our data showed various beneficial effects of licorice roots extract including induction of apoptosis and cell cycle arrest. Second, upregulating tumor suppressor miRNAs; let7a-3p, miR-34c-5p, miR-122-5p, miR-126-3p, miR195-5p, miR-199a-5p, miR-206, and miR-326-5p. Third, inhibiting HIF1α, PI3K and C-Myc and activating AMPK and p53. Fourth, inhibiting enzymes of glycolysis; HK-2, LDH-A and PK-M2; pentose phosphate pathway; G6PD and glutaminolysis; glutaminase. However, such an extract upregulated oncogenic miRNAs; miR-21, miR-221, and miR-222. Although the present data highlights the ability of licorice roots extract to enhance apoptosis and cell cycle arrest and correct altered metabolism, it warns against its unfavorable effects, hence, its use for prevention and therapy should proceed with caution. Further experiments are required to investigate whether a specific bioactive ingredient is responsible for upregulating the oncogenic miRNAs.

The Role of Non-coding RNAs in Oncology

For decades, research into cancer biology focused on the involvement of protein-coding genes. Only recently was it discovered that an entire class of molecules, termed non-coding RNA (ncRNA), plays key regulatory roles in shaping cellular activity. An explosion of studies into ncRNA biology has since shown that they represent a diverse and prevalent group of RNAs, including both oncogenic molecules and those that work in a tumor suppressive manner. As a result, hundreds of cancer-focused clinical trials involving ncRNAs as novel biomarkers or therapies have begun and these are likely just the beginning.

Molecular Mechanisms Regulating Obesity-Associated Hepatocellular Carcinoma

Obesity is a global, intractable issue, altering inflammatory and stress response pathways, and promoting tissue adiposity and tumorigenesis. Visceral fat accumulation is correlated with primary tumor recurrence, poor prognosis and chemotherapeutic resistance. Accumulating evidence highlights a close association between obesity and an increased incidence of hepatocellular carcinoma (HCC). Obesity drives HCC, and obesity-associated tumorigenesis develops via nonalcoholic fatty liver (NAFL), progressing to nonalcoholic steatohepatitis (NASH) and ultimately to HCC. The better molecular elucidation and proteogenomic characterization of obesity-associated HCC might eventually open up potential therapeutic avenues. The mechanisms relating obesity and HCC are correlated with adipose tissue remodeling, alteration in the gut microbiome, genetic factors, ER stress, oxidative stress and epigenetic changes. During obesity-related hepatocarcinogenesis, adipokine secretion is dysregulated and the nuclear factor erythroid 2 related factor 1 (Nrf-1), nuclear factor kappa B (NF-κB), mammalian target of rapamycin (mTOR), phosphatidylinositol-3-kinase (PI3K)/phosphatase and tensin homolog (PTEN)/Akt, and Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways are activated. This review captures the present trends allied with the molecular mechanisms involved in obesity-associated hepatic tumorigenesis, showcasing next generation molecular therapeutic strategies and their mechanisms for the successful treatment of HCC.

Application of transcriptomic and microRNA profiling in the evaluation of potential liver carcinogens

Hepatocarcinogens are agents that increase the incidence of liver cancer in exposed animals or humans. It is now established that carcinogenic exposures have a widespread impact on the transcriptome, inducing both adaptive and adverse changes in the activities of genes and pathways. Chemical hepatocarcinogens have also been shown to affect expression of microRNA (miRNA), the evolutionarily conserved noncoding RNA that regulates gene expression posttranscriptionally. Considerable effort has been invested into examining the involvement of mRNA in chemical hepatocarcinogenesis and their potential usage for the classification and prediction of new chemical entities. For miRNA, there has been an increasing number of studies reported over the past decade, although not to the same degree as for transcriptomic studies. Current data suggest that it is unlikely that any gene or miRNA signature associated with short-term carcinogen exposure can replace the rodent bioassay. In this review, we discuss the application of transcriptomic and miRNA profiles to increase mechanistic understanding of chemical carcinogens and to aid in their classification.

Non-Coding RNAs: Regulating Disease Progression and Therapy Resistance in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), the primary liver cancer arising from hepatocytes, is a universal health problem and one of the most common malignant tumors. Surgery followed by chemotherapy as well as tyrosine kinase inhibitors (TKIs), such as sorafenib, are primary treatment procedures for HCC, but recurrence of disease because of therapy resistance results in high mortality. It is necessary to identify novel regulators of HCC for developing effective targeted therapies that can significantly interfere with progression of the disease process. Non-coding RNAs (ncRNAs) are an abundant group of versatile RNA transcripts that do not translate into proteins, rather serve as potentially functional RNAs. The role of ncRNAs in regulating diverse aspects of the carcinogenesis process are gradually being elucidated. Recent advances in RNA sequencing technology have identified a plethora of ncRNAs regulating all aspects of hepatocarcinogenesis process and serving as potential prognostic or diagnostic biomarkers. The present review provides a comprehensive description of the biological roles of ncRNAs in disease process and therapy resistance, and potential clinical application of these ncRNAs in HCC.

The Underlying Mechanisms of Noncoding RNAs in the Chemoresistance of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most lethal human malignancies. Chemotherapeutic agents, such as sorafenib and lenvatinib, can improve the outcomes of HCC patients. Nevertheless, chemoresistance has become a major hurdle in the effective treatment of HCC. Noncoding RNAs (ncRNAs), including mircoRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), have been demonstrated to participate in the onset and progression of HCC. Moreover, multiple lines of evidence have indicated that ncRNAs also play a pivotal role in HCC drug resistance. ncRNAs can regulate drug efflux and metabolism, glucose metabolism, cellular death pathways, and malignant characteristics in HCC. A deeper understanding of the molecular mechanisms responsible for ncRNA-mediated drug resistance in HCC will provide new opportunities for improving the treatment of HCC. In this review, we summarize recent findings on the molecular mechanisms by which ncRNAs regulate HCC chemoresistance, as well as their potential clinical implications in overcoming HCC chemoresistance.

The role of noncoding RNAs in epithelial cancer

Regulatory noncoding RNAs (ncRNAs) are a class of RNAs transcribed by regions of the human genome that do not encode for proteins. The three main members of this class, named microRNA, long noncoding RNA, and circular RNA play a key role in the regulation of gene expression, eventually shaping critical cellular processes. Compelling experimental evidence shows that ncRNAs function either as tumor suppressors or oncogenes by participating in the regulation of one or several cancer hallmarks, including evading cell death, and their expression is frequently deregulated during cancer onset, progression, and dissemination. More recently, preclinical and clinical studies indicate that ncRNAs are potential biomarkers for monitoring cancer progression, relapse, and response to cancer therapy. Here, we will discuss the role of noncoding RNAs in regulating cancer cell death, focusing on those ncRNAs with a potential clinical relevance.

Expression profile of MicroRNA: An Emerging Hallmark of Cancer

MicroRNA (miRNAs), a class of small, endogenous non-coding RNA molecules of about 21-24 nucleotides in length, have unraveled a new modulatory network of RNAs that form an additional level of posttranscriptional gene regulation by targeting messenger RNAs (mRNAs). These miRNAs possess the ability to regulate gene expression by modulating the stability of mRNAs, controlling their translation rates, and consequently regulating protein synthesis. Substantial experimental evidence established the involvement of miRNAs in most biological processes like growth, differentiation, development, and metabolism in mammals including humans. An aberrant expression of miRNAs has been implicated in several pathologies, including cancer. The association of miRNAs with tumor growth, development, and metastasis depicts their potential as effective diagnostic and prognostic biomarkers. Furthermore, exploitation of the role of different miRNAs as oncogenes or tumor suppressors has aided in designing several miRNA-based therapeutic approaches for treating cancer patients whose clinical trials are underway. In this review, we aim to summarize the biogenesis of miRNAs and the dysregulations in these pathways that result in various pathologies and in some cases, resistance to drug treatment. We provide a detailed review of the miRNA expression signatures in different cancers along with their diagnostic and prognostic utility. Furthermore, we elaborate on the potential employment of miRNAs to enhance cancer cell apoptosis, regress tumor progression and even overcome miRNA-induced drug resistance.

MicroRNA-221 and MicroRNA-222 in Common Human Cancers: Expression, Function, and Triggering of Tumor Progression as a Key Modulator

MicroRNAs (miRNAs) are a class of short (~22 nucleotides [nt]), single-stranded RNA oligonucleotides that are regulatory in nature and are often dysregulated in various diseases, including cancer. miRNAs can act as oncomiRs (miRNAs associated with cancer) or tumor suppressor miRNAs and have the potential to be a diagnostic, prognostic, noninvasive biomarker for these diseases. MicroRNA-221 (miR-221) and microRNA-222 (miR-222) are homologous miRNAs, located on the human chromosome Xp11.3, which factored significantly in impairment in the regulation of a wide range of cancers. In this review, we have highlighted the most consistently reported dysregulated miRNAs that trigger human tissues to express cancerous features and surveyed the role of those miRNAs in metastasis, apoptosis, angiogenesis, and tumor prognosis. Also, we applied the causes of drug resistance and the role of coordinated actions of these miRNAs to epigenetic changes and selected miRNAs as a potential type of cancer treatment.

miRNAs as Influencers of Cell-Cell Communication in Tumor Microenvironment

microRNAs (miRNAs) are small noncoding RNAs that regulate gene expression at the posttranscriptional level, inducing the degradation of the target mRNA or translational repression. MiRNAs are involved in the control of a multiplicity of biological processes, and their absence or altered expression has been associated with a variety of human diseases, including cancer. Recently, extracellular miRNAs (ECmiRNAs) have been described as mediators of intercellular communication in multiple contexts, including tumor microenvironment. Cancer cells cooperate with stromal cells and elements of the extracellular matrix (ECM) to establish a comfortable niche to grow, to evade the immune system, and to expand. Within the tumor microenvironment, cells release ECmiRNAs and other factors in order to influence and hijack the physiological processes of surrounding cells, fostering tumor progression. Here, we discuss the role of miRNAs in the pathogenesis of multicomplex diseases, such as Alzheimer’s disease, obesity, and cancer, focusing on the contribution of both intracellular miRNAs, and of released ECmiRNAs in the establishment and development of cancer niche. We also review growing evidence suggesting the use of miRNAs as novel targets or potential tools for therapeutic applications.

Dissimilar Appearances Are Deceptive-Common microRNAs and Therapeutic Strategies in Liver Cancer and Melanoma

: In this review, we summarize the current knowledge on miRNAs as therapeutic targets in two cancer types that were frequently described to be driven by miRNAs-melanoma and hepatocellular carcinoma (HCC). By focusing on common microRNAs and associated pathways in these-at first sight-dissimilar cancer types, we aim at revealing similar molecular mechanisms that are evolved in microRNA-biology to drive cancer progression. Thereby, we also want to outlay potential novel therapeutic strategies. After providing a brief introduction to general miRNA biology and basic information about HCC and melanoma, this review depicts prominent examples of potent oncomiRs and tumor-suppressor miRNAs, which have been proven to drive diverse cancer types including melanoma and HCC. To develop and apply miRNA-based therapeutics for cancer treatment in the future, it is essential to understand how miRNA dysregulation evolves during malignant transformation. Therefore, we highlight important aspects such as genetic alterations, miRNA editing and transcriptional regulation based on concrete examples. Furthermore, we expand our illustration by focusing on miRNA-associated proteins as well as other regulators of miRNAs which could also provide therapeutic targets. Finally, design and delivery strategies of miRNA-associated therapeutic agents as well as potential drawbacks are discussed to address the question of how miRNAs might contribute to cancer therapy in the future.

Role of MicroRNA in the Diagnosis and Management of Hepatocellular Carcinoma

INTRODUCTION

Hepatocellular Carcinoma (HCC) is one of the most common malignant tumors in the world and comes third in cancer-induced mortality. The need for improved and more specific diagnostic methods that can detect early-stage disease is immense, as it is amenable to curative modalities, while advanced HCC is associated with low survival rates. microRNA (miRNA) expression is deregulated in HCC and this can be implemented both diagnostically and therapeutically.

OBJECTIVE

To provide a concise review on the role of miRNA in diagnosis, prognosis, and treatment of HCC.

METHODS

We conducted a comprehensive review of the PubMed bibliographic database.

RESULTS

Multiple miRNAs are involved in the pathogenesis of HCC. Measurement of the levels of these miRNAs either in tumor tissue or in the blood constitutes a promising diagnostic, as well as prognostic tool. OncomiRs are miRNAs that promote tumorigenesis, thus inhibiting them by administering antagomiRs is a promising treatment option. Moreover, replacement of the depleted miRNAs is another potential therapeutic approach for HCC. Modification of miRNA levels may also regulate sensitivity to chemotherapeutic agents.

CONCLUSION

miRNA play a pivotal role in HCC pathogenesis and once the underlying mechanisms are elucidated, they will become part of everyday clinical practice against HCC.

MicroRNA-Based Combinatorial Cancer Therapy: Effects of MicroRNAs on the Efficacy of Anti-Cancer Therapies

The susceptibility of cancer cells to different types of treatments can be restricted by intrinsic and acquired therapeutic resistance, leading to the failure of cancer regression and remission. To overcome this problem, a combination therapy has been proposed as a fundamental strategy to improve therapeutic responses; however, resistance is still unavoidable. MicroRNA (miRNAs) are associated with cancer therapeutic resistance. The modulation of dysregulated miRNA levels through miRNA-based therapy comprising a replacement or inhibition approach has been proposed to sensitize cancer cells to other anti-cancer therapies. The combination of miRNA-based therapy with other anti-cancer therapies (miRNA-based combinatorial cancer therapy) is attractive, due to the ability of miRNAs to target multiple genes associated with the signaling pathways controlling therapeutic resistance. In this article, we present an overview of recent findings on the role of therapeutic resistance-related miRNAs in different types of cancer. We review the feasibility of utilizing dysregulated miRNAs in cancer cells and extracellular vesicles as potential candidates for miRNA-based combinatorial cancer therapy. We also discuss innate properties of miRNAs that need to be considered for more effective combinatorial cancer therapy.

CircRNA-5692 inhibits the progression of hepatocellular carcinoma by sponging miR-328-5p to enhance DAB2IP expression

Circular RNAs (circRNAs), one kind of noncoding RNAs, can interact with miRNA and transcription factors to regulate gene expression. However, little is known on which circRNA is crucial for the pathogenesis of hepatocellular carcinoma (HCC). CircRNA expression profile was analyzed by a microarray. Regulatory gene targets were predicted by bioinformatics analysis and validated by luciferase assay. Their expression was determined by qRT-PCR and Western blotting. DNA methylation was determined by methylation-specific PCR. Gene knockdown and overexpression were mediated by lentivirus-mediated shRNA and transfection with plasmids for cDNA expression, respectively. MTT assay, wound-healing assay, transwell invasion assay, and flow cytometry were used to determine malignant behaviors of HCC cells. HCC xenograft mouse model was used to determine the in vivo effects of circRNA-5692. CircRNA-5692 expression was downregulated in HCC tissues, and circRNA-5692 overexpression attenuated the malignant behaviors of HCC cells. Bioinformatics predicted that circRNA-5692 interacted with miR-328-5p, which targeted the DAB2IP mRNA. Actually, miR-328-5p promoted the malignant behaviors of HCC cells, while DAB2IP had opposite effects. Moreover, circRNA-5692 overexpression inhibited the growth of xenograft HCC tumors in vivo by decreasing miR-328-5p expression to enhance DAB2IP expression. In conclusion, the circRNA-5692–miR-328-5p–DAB2IP regulatory pathway inhibits the progression of HCC. Our findings may provide potential new targets for the diagnosis and therapy of HCC.

miR-221-3p and miR-15b-5p promote cell proliferation and invasion by targeting Axin2 in liver cancer

Globally, liver cancer has the third highest mortality rate among all types of cancer due to the invasive and metastatic capacities of liver tumor cells. MicroRNA (miR) is a class of non-coding RNAs that participate in the development of liver cancer. The aim of the present study was to explore the molecular mechanisms by which miR-221-3p and miR-15b-5p promote the proliferation and invasion of liver cancer cells through targeting axis formation inhibitor 2 (Axin2) and to identify suitable targets for the treatment of liver cancer. The expression levels of miR-221-3p and miR-15b-5p were determined in liver cancer tissues and cells by quantitative PCR, and the association between miR-221-3p, miR-15b-5p and Axin2 expression in liver cancer cells was analyzed using cell transfection. The results demonstrated that miR-221-3p and miR-15b-5p levels were upregulated in liver cancer tissues and cell lines, and results from predictive bioinformatic analysis and identification revealed that Axin2 was the common target gene of miR-221-3p and miR-15b-5p. miR-221-3p and miR-15b-5p may be used as prognostic indicators for liver cancer. The miR-221-3p/miR-15b-5p-Axin2 axis may serve as a therapeutic target in patients with liver cancer.

MicroRNAs as Potential Biomarkers of Insecticide Exposure: A Review

Insecticides are key weapons for the control of pests. Large scale use of insecticides is harmful to the ecosystem, which is made up of a wide range of species and environments. MicroRNAs (miRNAs) are a class of endogenous single-stranded noncoding small RNAs in length of 20-24 nucleotides (nt), which extensively regulate expression of genes at transcriptional and post-transcriptional levels. The current research on miRNA-induced insecticide resistance reveals that dysregulated miRNAs cause significant changes in detoxification genes, particularly cytochrome P450s. Meanwhile, insecticide-induced changes in miRNAs are related to the decline of honeybees and threatened the development of zebrafish and other animals. Additionally, miRNAs are involved in insecticide-induced cytotoxicity, and dysregulated miRNAs are associated with human occupational and environmental exposure to insecticides. Therefore, miRNAs are valuable novel biomarkers of insecticide exposure, and they are potential factors to explain the toxicological effects of insecticides.

The reduction of miR146b-5p in monocytes and T cells could contribute to the immunopathogenesis of hepatitis C virus infection

It has been reported that various kinds of miRNAs could affect the pathogenesis of hepatitis C virus infection. Recently, our group reported that deep-sequencing analysis was useful to detect disease-specific miRNAs. The aim of this study is to identify the HCV-specific miRNAs that could contribute to the immunopathogenesis of HCV by using clinical samples and in vitro analysis. Five miRNAs (hsa-miR181a-2-3p, hsa-miR-374a-3p, hsa-miR374a-5p, hsa-miR-204-5p and hsa-miR146b-5p) were shown to be significantly downregulated in CH-C by deep sequence analysis. The average ratio (PBMCs miRNAs/serum miRNAs) of hsa-miR146b-5p was highest among all the miRNAs. Moreover, serum hsa-miR146b-5p was significantly down-regulated in CH-C patients in comparison to CH-B patients and healthy subjects. The expression of hsa-miR146b-5p in CD3⁺ T cells and CD14⁺ monocytes of CH-C patients was significantly lower than that of the other groups. The hsa-miR146b-5p expression in CD14⁺ monocytes of SVR patients treated with Peg-IFN/RBV was significantly higher than in those of non-SVR patients treated with Peg IFN/RBV. However, the hsa-miR146b-5p expression in CD14⁺ monocytes of SVR patients treated with DCV and ASV was comparable to that in monocytes of non-SVR patients treated with DCV and ASV. Moreover, the expression levels of hsa-miR146b-5p in CD14⁺ monocytes were significantly increased after achieving SVR and 1(OH)Vitamin D3 treatment. Further, the expression of HCV-Core could suppress miR146b-5p expression in immune cells and affect the expression of various kinds of cytokines by affecting the NF-κB signaling. In conclusion, the reduction of miR146b-5p in monocytes and T cells could contribute to the immunopathogenesis of hepatitis C virus infection.

Functional exosome-mediated co-delivery of doxorubicin and hydrophobically modified microRNA 159 for triple-negative breast cancer therapy

Exosomes (Exo) hold great promise as endogenous nanocarriers that can deliver biological information between cells. However, Exo are limited in terms of their abilities to target specific recipient cell types. We developed a strategy to isolate Exo exhibiting increased binding to integrin α_vβ₃. Binding occurred through a modified version of a disintegrin and metalloproteinase 15 (A15) expressed on exosomal membranes (A15-Exo), which facilitated co-delivery of therapeutic quantities of doxorubicin (Dox) and cholesterol-modified miRNA 159 (Cho-miR159) to triple-negative breast cancer (TNBC) cells, both in vitro and in vivo. The targeted A15-Exo were derived from continuous protein kinase C activation in monocyte-derived macrophages. These cell-derived Exo displayed targeting properties and had a 2.97-fold higher production yield. In vitro, A15-Exo co-loaded with Dox and Cho-miR159 induced synergistic therapeutic effects in MDA-MB-231 cells. In vivo, miR159 and Dox delivery in a vesicular system effectively silenced the TCF-7 gene and exhibited improved anticancer effects, without adverse effects. Therefore, our data demonstrate the synergistic efficacy of co-delivering miR159 and Dox by targeted Exo for TNBC therapy.

MicroRNA-2053 overexpression inhibits the development and progression of hepatocellular carcinoma

MicroRNAs (miRNAs) represent a class of small RNAs that participate in the regulation of tumor progression. However, the identification of functional miRNAs in tumors has not been thoroughly elucidated. In the present study we aim to investigate the impact of altered miR-2053 expression in hepatocellular carcinoma (HCC) cells. The results of the present study demonstrated that miR-2053 overexpression inhibited cell proliferation, migration and invasion, and promoted apoptosis in a HCC cell line, while miR-2053 knockdown induced the opposite cellular phenotypic changes. Mechanistically, it was found that overexpression of miR-2053 resulted in the downregulation of the phosphoinositide 3-kinase (PI3K) and Wnt/β-catenin signaling pathways, which are aberrantly expressed in HCC. Collectively, the results indicate that miR-2053 serves as a tumor suppressor with a crucial role in inhibiting the proliferation, migration and invasion of HCC via targeting the PI3K and Wnt/β-catenin signaling pathways. These data indicate a potential application of miR-2053 in cancer therapy.

MicroRNA-582-5p suppresses non-small cell lung cancer cells growth and invasion via downregulating NOTCH1

Non-small cell lung cancer (NSCLC) is the most common cancer worldwide. MicroRNAs have been shown to be correlated with biological processes of various tumors. In this study, we observed that the expression of miR-582-5p was lower in NSCLC tissues than that in para-carcinoma tissues. Ectopic expression of miR-582-5p significantly inhibited NCI-H358 cell proliferation and invasion. Knockdown of miR-582-5p showed the opposite results, with cell growth rate and the invasive capacity of PC-9 cells enhanced. Furthermore, we elucidated that NOTCH1 is a target of miR-582-5p and there is an inverse correlation between miR-582-5p and NOTCH1 expression in NSCLC tissues. Overexpression of NOTCH1 in miR-582-5p-overexpressing NCI-H358 cells could partially reverse the inhibition of cell proliferation and invasion by miR-582-5p. Thus, our research demonstrated that miR-582-5p suppresses NSCLC cell lines’ growth and invasion via targeting oncoprotein NOTCH1 and restoration of miR-582-5p might be feasible therapeutic strategy for NSCLC.

miRNAs and their roles in KSHV pathogenesis

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman Disease (MCD). Recent mechanistic advances have discerned the importance of microRNAs in the virus-host relationship. KSHV has two modes of replication: lytic and latent phase. KSHV entry into permissive cells, establishment of infection, and maintenance of latency are contingent upon successful modulation of the host miRNA transcriptome. Apart from host cell miRNAs, KSHV also encodes viral miRNAs. Among various cellular and molecular targets, miRNAs are appearing to be key players in regulating viral pathogenesis. Therefore, the use of miRNAs as novel therapeutics has gained considerable attention as of late. This innovative approach relies on either mimicking miRNA species by identical oligonucleotides, or selective silencing of miRNA with specific oligonucleotide inhibitors. Here, we provide an overview of KSHV pathogenesis at the molecular level with special emphasis on the various roles miRNAs play during virus infection.

Hepatocyte-specific suppression of microRNA-221-3p mitigates liver fibrosis

BACKGROUND & AIMS

Fibrosis, a cardinal feature of a dysfunctional liver, significantly contributes to the ever-increasing mortality due to end-stage chronic liver diseases. The crosstalk between hepatocytes and hepatic stellate cells (HSCs) plays a key role in the progression of fibrosis. Although ample efforts have been devoted to elucidate the functions of HSCs during liver fibrosis, the regulatory functions of hepatocytes remain elusive.

METHODS

Using an unbiased functional microRNA (miRNA) screening, we investigated the ability of hepatocytes to regulate fibrosis by fine-tuning gene expression via miRNA modulation. The in vivo functional analyses were performed by inhibiting miRNA in hepatocytes using adeno-associated virus in carbon-tetrachloride- and 3,5-di-diethoxycarbonyl-1,4-dihydrocollidine-induced liver fibrosis.

RESULTS

Blocking miRNA-221-3p function in hepatocytes during chronic liver injury facilitated recovery of the liver and faster resolution of the deposited extracellular matrix. Furthermore, we demonstrate that reduced secretion of C-C motif chemokine ligand 2, as a result of post-transcriptional regulation of GNAI2 (G protein alpha inhibiting activity polypeptide 2) by miRNA-221-3p, mitigates liver fibrosis.

CONCLUSIONS

Collectively, miRNA modulation in hepatocytes, an easy-to-target cell type in the liver, may serve as a potential therapeutic approach for liver fibrosis.

LAY SUMMARY

Liver fibrosis majorly contributes to mortality resulting from various liver diseases. We discovered a small RNA known as miRNA-221-3p, whose downregulation in hepatocytes results in reduced liver fibrosis. Thus, inhibition of miRNA-221-3p may serve as one of the therapeutic approaches for treatment of liver fibrosis.