The role of microRNAs in human liver cancers

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.

Increased hsa-miR-100-5p Expression Improves Hepatocellular Carcinoma Prognosis in the Asian Population with PLK1 Variant rs27770A>G

Hepatocellular carcinoma (HCC) has the highest incidence and mortality in the Asian population, and race is an independent risk factor affecting survival time in liver cancer. Micro RNAs (miRNAs) are remarkably dysregulated in HCC and closely associated with HCC prognosis. Recent studies show that genetic variability between ethnic groups may result in differences in the specificity of HCC miRNA biomarkers. Here, we reveal a high expression level of hsa-miR-100-5p, an HCC prognosis-related miRNA, which improves HCC prognosis in the Asian Population with Polo-like kinase 1 (PLK1) variant rs27770A>G. In this study, we discovered that hsa-miR-100-5p was downregulated in various HCC cell lines. While mimics transient transfection and mouse liver cancer model confirmed the interaction between hsa-miR-100-5p and PLK1, a stratified analysis based on the Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA-LIHC) data suggest both low hsa-miR-100-5p expression level and high PLK1 expression level associated with poor HCC prognosis, especially in the Asian population. According to the 1000 Genomes Project database, the SNP rs27770 located in 3'UTR of PLK1 had a significantly higher G allele frequency in the East Asian population. Bioinformatics analysis suggested that rs27770 A>G affects PLK1 mRNA secondary structure and alters the hsa-miR-100-5p/PLK1 interaction by forming an additional seedless binding site. This racial variation caused PLK1 to be more vulnerable to hsa-miR-100-5p inhibition, resulting in hsa-miR-100-5p being more favorable for HCC prognosis in the Asian population.

Non-Coding RNAs in Hepatocellular Carcinoma

Liver cancer ranks as the fourth leading cause of cancer-related deaths. Despite extensive research efforts aiming to evaluate the biological mechanisms underlying hepatocellular carcinoma (HCC) development, little has been translated towards new diagnostic and treatment options for HCC patients. Historically, the focus has been centered on coding RNAs and their respective proteins. However, significant advances in sequencing and RNA detection technologies have shifted the research focus towards non-coding RNAs (ncRNA), as well as their impact on HCC development and progression. A number of studies reported complex post-transcriptional interactions between various ncRNA and coding RNA molecules. These interactions offer insights into the role of ncRNAs in both the known pathways leading to oncogenesis, such as dysregulation of p53, and lesser-known mechanisms, such as small nucleolar RNA methylation. Studies investigating these mechanisms have identified prevalent ncRNA changes in microRNAs, snoRNAs, and long non-coding RNAs that can both pre- and post-translationally regulate key factors in HCC progression. In this review, we present relevant publications describing ncRNAs to summarize the impact of different ncRNA species on liver cancer development and progression and to evaluate recent attempts at clinical translation.

Low adipocyte hepatocellular carcinoma is associated with aggressive cancer biology and with worse survival

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide, and non-alcoholic fatty liver disease is strongly associated with its development. To explore the role of adipocytes in HCC, we investigated intratumoral adipocytes, also known as cancer-associated adipocytes (CAA). Based on our prior breast cancer findings, we hypothesized that low intratumoral adipocytes would be associated with aggressive cancer biology, worse tumor microenvironment (TME), and clinical outcomes. The Cancer Genome Atlas (TCGA) was used and validated by the Gene Expression Omnibus (GEO) cohort. xCell algorithm was used to quantify intratumoral adipocytes and top 90% were defined as adipocyte high (AH) and bottom 10% as adipocyte low (AL). We found that AL-HCC was significantly associated with worse disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS). AL-HCC were higher-grade, had high MKI67 expression, enriched cell proliferation-related gene sets, and had increased altered fraction, aneuploidy, and homologous recombination defects. Also, anti-cancer immune cells, CD8, Th1, and M1 cells, as well as pro-cancer Th2 cells were increased in AL-HCC. Micro-RNAs miR-122 (associated with cholesterol metabolism) and miR-885 (associated with liver pathologies) were significantly increased in the AL TME. In conclusion, we found that AL-HCC has worse patient outcomes and is biologically more aggressive with enhanced cell proliferation. Our findings take initial steps to clarify the role of adipocytes in HCC.

Exome sequencing of hepatocellular carcinoma in lemurs identifies potential cancer drivers: A pilot study

Background and objectives

Hepatocellular carcinoma occurs frequently in prosimians, but the cause of these liver cancers in this group is unknown. Characterizing the genetic changes associated with hepatocellular carcinoma in prosimians may point to possible causes, treatments and methods of prevention, aiding conservation efforts that are particularly crucial to the survival of endangered lemurs. Although genomic studies of cancer in non-human primates have been hampered by a lack of tools, recent studies have demonstrated the efficacy of using human exome capture reagents across primates.

Methodology

In this proof-of-principle study, we applied human exome capture reagents to tumor-normal pairs from five lemurs with hepatocellular carcinoma to characterize the mutational landscape of this disease in lemurs.

Results

Several genes implicated in human hepatocellular carcinoma, including ARID1A, TP53 and CTNNB1, were mutated in multiple lemurs, and analysis of cancer driver genes mutated in these samples identified enrichment of genes involved with TP53 degradation and regulation. In addition to these similarities with human hepatocellular carcinoma, we also noted unique features, including six genes that contain mutations in all five lemurs. Interestingly, these genes are infrequently mutated in human hepatocellular carcinoma, suggesting potential differences in the etiology and/or progression of this cancer in lemurs and humans.

Conclusions and implications

Collectively, this pilot study suggests that human exome capture reagents are a promising tool for genomic studies of cancer in lemurs and other non-human primates.

Lay Summary

Hepatocellular carcinoma occurs frequently in prosimians, but the cause of these liver cancers is unknown. In this proof-of-principle study, we applied human DNA sequencing tools to tumor-normal pairs from five lemurs with hepatocellular carcinoma and compared the lemur mutation profiles to those of human hepatocellular carcinomas.

MicroRNA as a Potential Therapeutic Molecule in Cancer

Small noncoding RNAs, as post-translational regulators of many target genes, are not only markers of neoplastic disease initiation and progression, but also markers of response to anticancer therapy. Hundreds of miRNAs have been identified as biomarkers of drug resistance, and many have demonstrated the potential to sensitize cancer cells to therapy. Their properties of modulating the response of cells to therapy have made them a promising target for overcoming drug resistance. Several methods have been developed for the delivery of miRNAs to cancer cells, including introducing synthetic miRNA mimics, DNA plasmids containing miRNAs, and small molecules that epigenetically alter endogenous miRNA expression. The results of studies in animal models and preclinical studies for solid cancers and hematological malignancies have confirmed the effectiveness of treatment protocols using microRNA. Nevertheless, the use of miRNAs in anticancer therapy is not without limitations, including the development of a stable nanoconstruct, delivery method choices, and biodistribution. The aim of this review was to summarize the role of miRNAs in cancer treatment and to present new therapeutic concepts for these molecules. Supporting anticancer therapy with microRNA molecules has been verified in numerous clinical trials, which shows great potential in the treatment of cancer.

Chimeric nanocomposites for the rapid and simple isolation of urinary extracellular vesicles

Cancer cell-derived extracellular vesicles (EVs) are promising biomarkers for cancer diagnosis and prognosis. However, the lack of rapid and sensitive isolation techniques to obtain EVs from clinical samples at a sufficiently high yield limits their practicability. Chimeric nanocomposites of lactoferrin conjugated 2,2-bis(methylol)propionic acid dendrimer-modified magnetic nanoparticles (LF-bis-MPA-MNPs) are fabricated and used for simple and sensitive EV isolation from various biological samples via a combination of electrostatic interaction, physically absorption, and biorecognition between the surfaces of the EVs and the LF-bis-MPA-MNPs. The speed, efficiency, recovery rate, and purity of EV isolation by the LF-bis-MPA-MNPs are superior to those obtained by using established methods. The relative expressions of exosomal microRNAs (miRNAs) from isolated EVs in cancerous cell-derived exosomes are verified as significantly higher than those from noncancerous ones. Finally, the chimeric nanocomposites are used to assess urinary exosomal miRNAs from urine specimens from 20 prostate cancer (PCa), 10 benign prostatic hyperplasia (BPH), patients and 10 healthy controls. Significant up-regulation of miR-21 and miR-346 and down-regulation of miR-23a and miR-122-5p occurs in both groups compared to healthy controls. LF-bis-MPA-MNPs provide a rapid, simple, and high yield method for human excreta analysis in clinical applications.

ERα inhibits mesenchymal and amoeboidal movement of liver cancer cell via Gα12

Hepatocellular carcinoma (HCC) is the second most common cancer worldwide, demonstrating aggressiveness and mortality more frequently in men than in women. Despite reports regarding the inhibitory ability of estrogen receptor alpha (ERα, ESR1) in certain cancer progression, targets and the basis of underlying gender disparity in HCC worsening remain elusive. Here, we report the ability of ERα to transcriptionally inhibit G protein subunit alpha 12 (Gα12) responsible for HCC worsening. First, using human samples and public database, the expression of ERα and Gα12 in HCC was examined. Then, quantitative real-time PCR, chromatin immunoprecipitation-assay, luciferase assay, and immunoblottings of liver cancer cell lines confirmed the inhibitory ability of ERα on Gα12 and HCC progression. Gα12 promoted mesenchymal characteristics and amoeboidal movement, which was antagonized by ERα overexpression. Additionally, we found microRNA-141 and -200a as downstream targets of the Gα12 signaling axis for cancer malignancy regulation under the control of ERα. As for in-depth mechanism, PTP4A1 was found to be directly inhibited by microRNA-141 and -200a. Moreover, we found the inhibitory effect of ERα on amoeboidal movement by analyzing the morphology and blebbing of liver cancer cells and the active form of MLC levels. The identified targets and ESR1 levels are inversely correlated in human specimens, as well as with sex-biased survival rates of HCC patients. Collectively, ERα-dependent repression of Gα12 and consequent changes in the Gα12 signaling may explain the gender disparity in HCC, providing pharmacological clues for the control of metastatic HCC. This article is protected by copyright. All rights reserved.

Long Non-coding RNAs, Lnc(ing) RNA Metabolism to Cancer Biology

The eukaryotic genome is represented by a vast proportion of non-coding regions, which in recent years have been attributed to have important functional roles in gene regulation through a myriad of processes, ranging from proper localization, correct folding and, most importantly, spatial and temporally regulated expression of genes. One of the major contributing factors in these processes is ribonucleic acid (RNA) metabolism, which comprises the RNA-nucleoprotein (RNP) complexes that interact with and instruct the genome to function. Long non-coding RNAs are an integral component of several RNPs, and herein we provide an overview of the understanding of the long non-coding RNAs, their characteristics, their function and their balancing act as dual modulators in cancer manifestation and progression.

miRNA and long non-coding RNA transcriptional expression in hepatocellular carcinoma cell line-secreted extracellular vesicles

Extracellular vesicles (EVs) are membrane-released vesicles acting as transporters of proteins, lipids and short/long non-coding RNA (miRNAs and lncRNAs). They are released by normal and pathological cells, including hepatocellular carcinoma (HCC). To date, studies focused on miRNAs and lncRNAs contained in EVs derived from HCC are limited. Our aim was to analyze the transcriptional profile of potential regulating miRNAs and lncRNAs in EVs secreted by HCC tumor cell line (HepG2, n = 6), and from a non-tumorigenic hepatocyte cell line (WRL68, n = 6), to compare their differential expression profile and to identify novel molecular diagnostic markers of HCC. EVs were isolated from the conditioned medium, through differential centrifugations. The expression profile of miRNAs (miR-23a, miR-16-2, miR-181a, miR-373, miR-205, miR-27a, miR-1323, and miR-532) and lncRNAs (HULC, HOTAIR, XIST, MALAT-1, GAS-5, H19) was performed in Real-time PCR, and their transcript was found both in HepG2 and WRL68 EVs. Lower miR-181a, miR-205 and miR-1323 expression were detected in EVs secreted by HepG2 compared to WRL68, while an opposite trend was observed for miR-23a, miR-16-2, miR-373, miR-27a, and miR-532. Several significant correlations were found between miRNA and lncRNA. An in silico analysis was also performed. The results obtained could identified them as new potential diagnostic and prognostic biomarkers of HCC.

Deregulation of the cell cycle and related microRNA expression induced by vinyl chloride monomer in the hepatocytes of rats

Vinyl chloride (VC) is a confirmed human carcinogen associated with hepatocellular carcinoma and angiosarcoma. However, the role of microRNAs (miRNAs) in liver cell cycle changes under VC exposure remains unclear, which prevents research on the mechanism of VC-induced carcinogenesis. In this study, male rats were injected intraperitoneally with VC (0, 5, 25, and 125 mg/kg body weight) for 6, 8, and 12 weeks. Cell cycle analysis of liver cells, miRNA-222, miRNA-199a, miRNA-195, and miRNA-125b expression in the liver and serum, and target protein expression were performed at different time points. The results showed a higher percentage of hepatocytes in the G1/G0 and S phases at the end of 6 and 12 weeks of VC exposure, respectively. MiRNA-222 expression decreased initially and then increased, whereas miRNA-199a, miRNA-195, and miRNA-125b expression increased initially and then decreased, which corresponded with changes in cell cycle distribution and related target proteins expression (p27, cyclinA, cyclinD1, and CDK6). The corresponding expression levels of miRNAs in serum did not change. Dynamic changes in miR-222, miR-199a, miR-195, and miR-125b induced by VC can lead to cell cycle deregulation by affecting cell cycle-related proteins, and these miRNAs can serve as early biomarkers for malignant transformation caused by VC.

MicroRNA signature in liver cancer

Liver cancer is the 7^th utmost frequent neoplasm and the 4^th principal source of cancer deaths. This malignancy is linked with several environmental and lifestyle-related factors emphasizing the role of epigenetics in its pathogenesis. MicroRNAs (miRNAs) have been regarded as potent epigenetic mechanisms partaking in the pathogenesis of liver cancer. Dysregulation of miRNAs has been related with poor outcome of patients with liver cancer. In the current manuscript, we provide a concise review of the results of recent studies about the role of miRNAs in the progression of liver cancer and their diagnostic and prognostic utility.

Acoustically Driven Microbubbles Enable Targeted Delivery of microRNA-Loaded Nanoparticles to Spontaneous Hepatocellular Neoplasia in Canines

Spatially localized microbubble cavitation by ultrasound offers an effective means of altering permeability of natural barriers (i.e. blood vessel and cell membrane) in favor of nanomaterials accumulation in the target site. In this study, a clinically relevant, minimally invasive ultrasound guided therapeutic approach is investigated for targeted delivery of anticancer microRNA loaded PLGA-b-PEG nanoparticles to spontaneous hepatocellular neoplasia in a canine model. Quantitative assessment of the delivered microRNAs revealed prominent and consistent increase in miRNAs levels (1.5-to 2.3-fold increase (p<0.001)) in ultrasound treated tumor regions compared to untreated control regions. Immunohistology of ultrasound treated tumor tissue presented a clear evidence for higher amount of nanoparticles extravasation from the blood vessels. A distinct pattern of cytokine expression supporting CD8+ T cells mediated "cold-to-hot" tumor transition was evident in all patients. On the outset, proposed platform can enhance delivery of miRNA-loaded nanoparticles to deep seated tumors in large animals to enhance chemotherapy.

Advances in the pathogenesis and treatment of nut carcinoma: a narrative review

NUT carcinoma (NC) is a rare, highly invasive and fatal tumor and often misdiagnosed. It typically arises from the mediastinum and midline organs and has complicated pathogenesis and poor outcome. Genetically, its pathogenesis is related to a chromosomal rearrangement involving the NUTM1 gene. In most cases, the main oncoprotein is BRD4-NUT with a translocation between NUTM1 and BRD4 genes, but in a few cases, the oncoprotein is BRD3-NUT, or NSD3-NUT. Studies have shown that the histone hyperacetylation and BRD4 hyperphosphorylation may lead to the activation of cancer circuits. Abnormal production of microRNA, inactivation of tumor suppressor genes and abnormal activation of several signaling pathways are proposed as potential mechanisms underlying the pathogenesis of NC. Currently, there is no consensus on its standard treatment for NC. Extent of surgical resection with negative margins, initial radiotherapy and part of chemotherapy regimens may significantly associated with the improvement of progression-free survival (PFS) rate and overall survival (OS) rate. Some bromodomain and extraterminal inhibitors (BETis) have shown encouraging results in the clinical trials on NC, but delayed drug resistance is still an important issue that needs to be resolved. Histone deacetylase inhibitors are also found to possess the potential in the treatment of NC. Herein, we summarize recent advances in the pathogenesis and treatment of NC.

MicroRNA-587 Functions as a Tumor Suppressor in Hepatocellular Carcinoma by Targeting Ribosomal Protein SA

Background

Hepatocellular carcinoma (HCC) is one of the most highly aggressive cancer worldwide with an extremely poor prognosis. Evidence has revealed that microRNA-587 (miR-587) is abnormally expressed in a series of cancers. However, its expressions and functions in HCC have not been clearly acknowledged.

Methods

We detected the expression level of miR-587 both in the Gene Expression Omnibus (GEO) database and 86 paired clinical HCC tissues together with paired adjacent normal tissues by quantitative real-time PCR (qRT-PCR). Afterwards, the transfected HCC cell line SMMC-7721 cells were collected for the cell proliferation assay, cell-cycle arrest, cell migration, and invasion assays to explore the roles of miR-587 in regulating cellular function. In addition, bioinformatics analysis, combined with qRT-PCR and dual-luciferase reporter assays, were performed to confirm whether ribosomal protein SA (RPSA) mRNA was the direct target gene of miR-587. Moreover, the Cancer Genome Atlas (TCGA) and GEO databases as well as 86 paired clinical HCC tissues were used to verify the negative regulation between miR-587 and RPSA.

Results

In the present study, both the GEO database (GSE36915 and GSE74618) analysis and qRT-PCR analysis of 86 paired clinical tissues showed that miR-587 was significantly downregulated in HCC tissues. The overexpression of miR-587 inhibited proliferation, cell cycle, migration, and invasion in SMMC-7721 cells. In addition, miR-587 directly interacted with the 3′-untranslated region (UTR) of RPSA. Moreover, miR-587 overexpression directly suppressed RPSA expression, and the two genes were inversely expressed in HCC based on the analyses in TCGA and GEO (GSE36376) databases and qPCR analysis of 86 paired clinical tissues.

Conclusion

Our results demonstrate that miR-587 is downexpressed in HCC and regulates the cellular function by targeting RPSA.

Multipotent miRNA Sponge-Loaded Magnetic Nanodroplets with Ultrasound/Magnet-Assisted Delivery for Hepatocellular Carcinoma Therapy

Gene therapy is likely to be the most promising way to tackle cancer, while defects in molecular strategies and delivery systems have led to an impasse in clinical application. Here, it is found that onco-miRNAs of the miR-515 and -449 families were upregulated in hepatocellular carcinoma (HCC), and the sponge targeting miR-515 family had a significant probability to suppress cancer cell proliferation. Then, we constructed non-toxic sponge-loaded magnetic nanodroplets containing 20% C6F14 (SLMNDs-20%) that are incorporated with fluorinated superparamagnetic iron oxide nanoparticles enhancing external magnetism-assisted targeting and enabling a direct visualization of SLMNDs-20% distribution in vivo via magnetic resonance imaging monitoring. SLMNDs-20% could be vaporized by programmable focused ultrasound (FUS) activation, achieving ∼45% in vitro sponge delivery efficiency and significantly enhancing in vivo sponge delivery without a clear apoptosis. Moreover, the sponge-1-carrying SLMNDs-20% could effectively suppress proliferation of xenograft HCC after FUS exposure because sponge-1-suppressing onco-miR-515 enhanced the expression of anti-oncogenes (P21, CD22, TIMP1, NFKB, and E-cadherin) in cancer cells. The current results indicated that ultrasonic cavitation-inducing sonoporation enhanced the intracellular delivery of sponge-1 using SLMNDs-20% after magnetic-assisted accumulation, which was a therapeutic approach to inhibit HCC progression.

Synthetic circular miR-21 RNA decoys enhance tumor suppressor expression and impair tumor growth in mice

Naturally occurring circular RNAs efficiently impair miRNA functions. Synthetic circular RNAs may thus serve as potent agents for miRNA inhibition. Their therapeutic effect critically relies on (i) the identification of optimal miRNA targets, (ii) the optimization of decoy structures and (iii) the development of efficient formulations for their use as drugs. In this study, we extensively explored the functional relevance of miR-21-5p in cancer cells. Analyses of cancer transcriptomes reveal that miR-21-5p is the by far most abundant miRNA in human cancers. Deletion of the MIR21 locus in cancer-derived cells identifies several direct and indirect miR-21-5p targets, including major tumor suppressors with prognostic value across cancers. To impair miR-21-5p activities, we evaluate synthetic, circular RNA decoys containing four repetitive binding elements. In cancer cells, these decoys efficiently elevate tumor suppressor expression and impair tumor cell vitality. For their in vivo delivery, we for the first time evaluate the formulation of decoys in polyethylenimine (PEI)-based nanoparticles. We demonstrate that PEI/decoy nanoparticles lead to a significant inhibition of tumor growth in a lung adenocarcinoma xenograft mouse model via the upregulation of tumor suppressor expression. These findings introduce nanoparticle-delivered circular miRNA decoys as a powerful potential therapeutic strategy in cancer treatment.

Long Noncoding RNA ST7-AS1 Upregulates TRPM7 Expression by Sponging microRNA-543 to Promote Cervical Cancer Progression

Purpose

ST7 antisense RNA 1 (ST7-AS1) is a long noncoding RNA that affects the progression of gastric cancer and laryngeal squamous cell carcinoma. Herein, ST7-AS1 expression was detected in cervical cancer tissues and cell lines. In addition, its biological roles in inducing the aggressive phenotype of cervical cancer and its associated mechanisms of action were illustrated.

Patients and Methods

ST7-AS1 expression in cervical cancer tissues and cell lines was detected using quantitative real-time polymerase chain reaction (qRT-PCR). Malignancy was determined using Cell Counting Kit-8 assay, flow cytometry, transwell migration and invasion assays, and xenograft experiments. Bioinformatics analysis was performed to predict the interaction between ST7-AS1 and microRNA-543 (miR-543). Luciferase reporter assay, RNA immunoprecipitation assay, Western blotting, qRT-PCR, and rescue experiments were performed to further identify the interactions among ST7-AS1, miR-543, and transient receptor potential melastatin 7 (TRPM7).

Results

ST7-AS1 was upregulated in cervical cancer tissues and cell lines. ST7-AS1 overexpression was correlated with a high International Federation of Gynecology and Obstetrics stage, frequent lymph node metastasis, deep cervical invasion, and short overall survival in patients with cervical cancer. ST7-AS1 inhibition hindered cervical cancer cell proliferation, migration, and invasion; ST7-AS1 downregulation resulted in marked cell apoptosis. Additionally, ST7-AS1 deficiency restricted cervical tumor growth in vivo. Mechanistically, ST7-AS1 functioned as competing endogenous RNA to increase TRPM7 expression by sponging miR-543. Intriguingly, rescue experiments revealed that miR-543 downregulation or TRPM7 overexpression abrogated the inhibitory actions of ST7-AS1 knockdown in the aggressive phenotype of cervical cancer cells.

Conclusion

The newly identified ST7-AS1/miR-543/TRPM7 axis promoted the oncogenicity of cervical cancer cells both in vitro and in vivo. Our study highlighted the importance of this novel axis in cervical cancer progression, suggesting that this pathway can serve as a promising therapeutic target for cervical cancer.

Tumor-suppressive miR-3650 inhibits tumor metastasis by directly targeting NFASC in hepatocellular carcinoma

In recent years, a growing body of evidence has provided support for the important role of microRNAs (miRNAs) in the progression of human cancers. A recent study showed that a novel miRNA miR-3650 expression was significantly decreased in hepatocellular carcinoma (HCC). However, the precise role of miR-3650 in HCC have remained poorly understood. In this study, we found that miR-3650 expression was frequently decreased in HCC tissues. Low expression of miR-3650 is positively associated with tumor metastasis and poor survival of HCC patients. Forced expression of miR-3650 significantly inhibited the migration and epithelial-mesenchymal transition (EMT) of HCC cells. Through bioinformatic analysis and luciferase assays, we confirmed that neurofascin (NFASC) is a directly target mRNA of miR-3650. Rescue experiment demonstrated that NAFSC overexpression could partially counteracted the inhibitory effect of miR-3650 in HCC metastasis and EMT. In conclusion, our findings are the first time to demonstrate that reduced expression of miR-3650 in HCC was correlated with tumor metastasis and poor survival. MiR-3650 repressed HCC migration and EMT by directly targeting NFASC. Our findings suggested that miR-3650 may serve as a potential prognostic marker and promising application in HCC therapy.

miR‑95 promotes osteosarcoma growth by targeting SCNN1A

Osteosarcoma (OS) is a common malignant bone tumor, presenting particularly in children and young adults, and accounts for approximately 19% of all malignant bone cancers. Despite advances in OS treatment, long-term prognosis remains poor. miRNAs are non-coding single-stranded RNAs ~22 nucleotides in length. Increasing evidence suggests that numerous miRNAs may play critical roles in tumorigenesis and tumor progression; however, the role of miR-95 in OS has not been examined. In the present study, we investigated the role of miR-95 in OS using in vitro and in vivo models and publicly available expression data. Our findings indicate that abnormal miR-95 expression occurs in OS, according to the Gene Expression Omnibus (GEO) database. The miR-95 inhibitor reduced cell proliferation and promoted apoptosis in OS cell lines as detected by EdU staining, TUNEL staining and flow cytometry. Furthermore, a dual luciferase reporter assay revealed that miR-95 regulates the cell cycle of OS cells and apoptosis by targeting sodium channel epithelial 1α subunit (SCNN1A). Additionally, miR-95 antagomir suppressed the growth of U2OS xenograft tumors in a mouse model. In summary, our results suggest that miR-95 induces OS growth in vitro and in vivo by targeting SCNN1A. Our results help clarify the mechanism underlying the miR-95-mediated effects on OS tumor growth, thus potentially establishing it as a diagnostic target.

Role of miR-18a and miR-25 disruption and its mechanistic pattern in progression of liver cancer

This study examined the molecular mechanisms underlying the roles of the microRNAs miR-18a and miR-25 in the progression of human liver cancer. Liver cancer biopsies obtained from early-stage liver cancer patients were examined by qRT-PCR and Northern blotting to examine the expression of miR-18a and miR-25. Both microRNAs were overexpressed in mouse primary hepatocytes following transfection of the cells with vectors encoding the microRNAs. An analysis of biopsy samples from liver cancer patients indicated that both miR-18a and miR-25 were overexpressed during the early stages of liver cancer. Further, qRT-PCR and Northern blotting confirmed that both of these microRNAs play crucial roles in the progression of liver cancer. Our findings clearly indicate that miR-18a and miR-25 can be used as prognostic biomarkers for early-stage liver cancer. Hence, miR-18a and miR-25 may have value as prognostic indicators and may facilitate the development of novel therapeutics for liver cancer.

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.

The Fas/FasL Signaling Pathway: Its Role in the Metastatic Process and as a Target for Treating Osteosarcoma Lung Metastases

Understanding how the tumor microenvironment participates in inhibiting or supporting tumor growth is critical for the development of novel therapies. Osteosarcoma (OS) metastasizes almost exclusively to the lung, an organ where Fas ligand (FasL) is constitutively expressed. This chapter focuses on our studies dedicated to the interaction of OS cells with the lung microenvironment. We will summarize our studies conducted over the past 20 years showing the importance of the Fas/FasL signaling pathway to the establishment and progression of OS metastases in the lung. We demonstrated that the FasL⁺ lung microenvironment eliminates Fas-positive (Fas⁺) OS cells that metastasize to the lungs, through apoptosis induced by Fas signaling following interaction of Fas on the tumor cell surface with FasL on the lung epithelial cells. Expression of the Fas receptor on OS cells inversely correlated with the ability of OS cells to form lung metastases. Blocking this pathway interferes with this process, allowing Fas⁺ cells to grow in the lung. By contrast, upregulation of Fas on Fas^- OS cells inhibited their ability to metastasize to the lung. We demonstrated how the FasL⁺ lung microenvironment can be leveraged for therapeutic intent through the upregulation of Fas expression. To this end, we demonstrated that the histone deacetylase inhibitor entinostat upregulated Fas expression on OS cells, reduced their ability to form lung metastases, and induced regression of established micrometastases. Fas expression in OS cells is regulated epigenetically by the microRNA miR-20a. We showed that expressions of Fas and miR-20a are inversely correlated, and that delivery of anti-miR-20a in vivo to mice with established osteosarcoma lung metastases resulted in upregulation of Fas and tumor regression. Therefore, targeting the Fas signaling pathway may present therapeutic opportunities, which target the lung microenvironment for elimination of OS lung metastases. We have also shown that in addition to being critically involved in the metastatic potential, the Fas signaling pathway may also contribute to the efficacy of chemotherapy. We demonstrated that the chemotherapeutic agent gemcitabine (GCB) increased Fas expression in both human and mouse OS cells in vitro. In vivo, aerosol GCB therapy induced upregulation of Fas expression and the regression of established osteosarcoma lung metastases. The therapeutic efficacy of GCB was contingent upon a FasL⁺ lung microenvironment as aerosol GCB had no effect in FasL-deficient mice. Manipulation of Fas expression and the Fas pathway should be considered, as this concept may provide additional novel therapeutic approaches for treating patients with OS lung metastases.

The long noncoding RNA FTH1P3 promotes the proliferation and metastasis of cervical cancer through microRNA‑145

Emerging evidence has revealed that long noncoding RNAs (lncRNAs) play crucial roles in the development and progression of tumors. The present study aimed to examine the roles and illustrate the underlying mechanisms of lncRNA ferritin heavy chain 1 pseudogene 3 (FTH1P3) in cervical cancer. The expression of lncRNA FTH1P3 and microRNA-145 (miRNA-145 or miR-145) in human cervical cancer samples and cervical cancer cell lines was detected by qRT-PCR (reverse transcription-quantitative polymerase chain reaction). FTH1P3 overexpression, siRNA plasmid, hsa-miR-145 mimic or hsa-miR-145 inhibitor were transfected. The target of FTH1P3 was predicted by bioinformatics analysis and validated by luciferase assay. Statistical significance analysis was performed by SPSS software. The results revealed that FTH1P3 was significantly upregulated in cervical cancer tissues compared with normal tissues. Increased expression of FTH1P3 was revealed in human cervical cancer cell lines compared with cervical normal epithelial cells. Downregulation of FTH1P3 inhibited cell proliferation, invasion and migration, and promoted apoptosis in cervical cancer cells. miR-145 was predicted and validated as a direct target of FTH1P3. Moreover, FTH1P3 siRNA partially attenuated the effects of the miR-145 inhibitor on cell viability and mobility in cervical cancer cells. The present results demonstrated that lncRNA FTH1P3 functioned as a promoting factor in cervical cancer by targeting miR-145.

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.

Interplay of Wnt β-catenin pathway and miRNAs in HBV pathogenesis leading to HCC

The prevalence of Hepatocellular carcinoma (HCC) has been identified world-wide. Plethora of factors including chronic infection of HBV/HCV has been characterized for the development of HCC. Although the onset and progression of HCC has been linked with awry of various signaling pathways but precise mechanism, still lies under the multitude layers of curiosity. HBV is spreading with insane speed throughout the world and has been found a main culprit in HCC development after regulating the several cellular pathways including Wnt/β-catenin, Raf/MAPK, Akt and affecting cell multiplication to genomic instability. The role of Wnt/FZD/β-catenin signaling pathway is centralized in liver functions and its anomalous activation leads to HCC development. β-catenin mainly plays a pivotal role in canonical pathway of the system. Altered mainly overexpression of β-catenin along its nuclear localization tunes the aberrations in liver functions and set disease progression. In the development of HCC, modulation of Wnt/FZD/β-catenin signaling pathway by HBV has been established. As HBV infects the cell it affects the miRNAs, the master regulators of cell. Previous studies showed the connection between HBV and cellular miRNAs. In the present review, we unveiled how HBV is deciphering the cellular miRNAs like miR-26a, miR-15a, miR-16-1, miR-148a, miR-132, miR-122, miR-34a, miR-21, miR-29a, miR-222 and miR-199a/b-3p to modulate the Wnt/FZD/β-catenin signaling pathway and develop HCC. These HBV mediated miRNAs may prove future therapeutic options to treat HBV-Wnt/FZD/β-catenin associated HCC.

Hepatocyte growth control by SOCS1 and SOCS3

The extraordinary capacity of the liver to regenerate following injury is dependent on coordinated and regulated actions of cytokines and growth factors. Whereas hepatocyte growth factor (HGF) and epidermal growth factor (EGF) are direct mitogens to hepatocytes, inflammatory cytokines such as TNFα and IL-6 also play essential roles in the liver regeneration process. These cytokines and growth factors activate different signaling pathways in a sequential manner to elicit hepatocyte proliferation. The kinetics and magnitude of these hepatocyte-activating stimuli are tightly regulated to ensure restoration of a functional liver mass without causing uncontrolled cell proliferation. Hepatocyte proliferation can become deregulated under conditions of chronic inflammation, leading to accumulation of genetic aberrations and eventual neoplastic transformation. Among the control mechanisms that regulate hepatocyte proliferation, negative feedback inhibition by the 'suppressor of cytokine signaling (SOCS)' family proteins SOCS1 and SOCS3 play crucial roles in attenuating cytokine and growth factor signaling. Loss of SOCS1 or SOCS3 in the mouse liver increases the rate of liver regeneration and renders hepatocytes susceptible to neoplastic transformation. The frequent epigenetic repression of the SOCS1 and SOCS3 genes in hepatocellular carcinoma has stimulated research in understanding the growth regulatory mechanisms of SOCS1 and SOCS3 in hepatocytes. Whereas SOCS3 is implicated in regulating JAK-STAT signaling induced by IL-6 and attenuating EGFR signaling, SOCS1 is crucial for the regulation of HGF signaling. These two proteins also module the functions of certain key proteins that control the cell cycle. In this review, we discuss the current understanding of the functions of SOCS1 and SOCS3 in controlling hepatocyte proliferation, and its implications to liver health and disease.

MicroRNA‑3653 inhibits the growth and metastasis of hepatocellular carcinoma by inhibiting ITGB1

microRNAs (miRNAs) play critical roles in hepatocellular carcinoma (HCC). However, the expression and biological function of miR-3653 in HCC remain unknown. The present study demonstrated that miR-3653 expression was significantly decreased in HCC tissues and cells using qRT-PCR. A decreased miR-3653 level was associated with unfavorable clinical features and poor prognosis of HCC patients. MTT, BrdU, Transwell and western blot assays showed that miR-3653 overexpression inhibited the growth, migration, invasion and epithelial-mesenchymal transition (EMT) of HCCLM3 cells while its knockdown promoted the growth and metastatic ability of Hep3B cells. In vivo experiments showed that miR-3653 overexpression inhibited the subcutaneous and the lung metastasis of HCCLM3 cells in nude mice. Mechanistically, integrin-β1 (ITGB1) was identified to be the downstream target of miR-3653 in HCC. ITGB1 overexpression reversed the inhibitory effects of miR-3653 on the growth, metastasis and EMT of HCCLM3 cells.

Hepatitis B virus X protein enhances hepatocarcinogenesis by depressing the targeting of NUSAP1 mRNA by miR-18b

Objective

The aim of this study was to investigate the underlying mechanism whereby HBx modulates the targeting of NUSAP1 by miR-18b to enhance hepatocarcinogenesis.

Methods

We employed an integrated approach of bioinformatics analysis and molecular experiments in hepatoma cells, HBV transgenic mice, and clinical liver cancer tissues to investigate the role of HBx-regulated miR-18b in the development of liver cancer.

Results

In this study, we report that the HBx-mediated tumor suppressor miR-18b modulates hepatocarcinogenesis during the host-HBV interaction. The expression levels of miR-18b were lower in clinical HBV-positive liver cancer tissues and liver tissues of HBV-transgenic mice. Interestingly, HBx inhibited miR-18b expression by inducing the methylation of CpG islands in its promoter. Accordingly, we tested the hypothesis that HBx enhanced hepatocarcinogenesis by increasing the expression of target genes of miR-18b. Moreover, we identified nucleolar spindle-associated protein 1 (NUSAP1) as one of the target genes of miR-18b. NUSAP1 was expressed at high levels in liver cancer tissues. Interestingly, HBx up-regulated NUSAP1 by suppressing miR-18b. Functionally, miR-18b significantly inhibited the proliferation of hepatoma cells by depressing NUSAP1 levels in vivo and in vitro.

Conclusions

Thus, we conclude that the targeting of NUSAP1 mRNA by the tumor suppressor miR-18b is controlled by HBx-modulated promoter methylation during the host-virus interaction, leading to hepatocarcinogenesis. Our findings provide new insights into the mechanism by which HBx-mediated miRNAs modulate hepatocarcinogenesis.

microRNAs: Key players in virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is known as one of the major health problems worldwide. Pathological analysis indicated that a variety of risk factors including genetical (i.e., alteration of tumor suppressors and oncogenes) and environmental factors (i.e., viruses) are involved in beginning and development of HCC. The understanding of these risk factors could guide scientists and clinicians to design effective therapeutic options in HCC treatment. Various viruses such as hepatitis B virus (HBV) and hepatitis C virus (HCV) via targeting several cellular and molecular pathways involved in HCC pathogenesis. Among various cellular and molecular targets, microRNAs (miRNAs) have appeared as key players in HCC progression. miRNAs are short noncoding RNAs which could play important roles as oncogenes or tumor suppressors in several malignancies such as HCC. Deregulation of many miRNAs (i.e., miR-222, miR-25, miR-92a, miR-1, let-7f, and miR-21) could be associated with different stages of HCC. Besides miRNAs, exosomes are other particles which are involved in HCC pathogenesis via targeting different cargos, such as DNAs, RNAs, miRNAs, and proteins. In this review, we summarize the current knowledge of the role of miRNAs and exosomes as important players in HCC pathogenesis. Moreover, we highlighted HCV- and HBV-related miRNAs which led to HCC progression.

Micro-RNAs in hepatitis B virus-related chronic liver diseases and hepatocellular carcinoma

MicroRNAs (miRNAs) are small non-coding RNAs that modulate gene expression at the post-transcriptional level by affecting both the stability and translation of complementary mRNAs. Several studies have shown that miRNAs are important regulators in the conflicting efforts between the virus (to manipulate the host for its successful propagation) and the host (to inhibit the virus), culminating in either the elimination of the virus or its persistence. An increasing number of studies report a role of miRNAs in hepatitis B virus (HBV) replication and pathogenesis. In fact, HBV is able to modulate different host miRNAs, particularly through the transcriptional transactivator HBx protein and, conversely, different cellular miRNAs can regulate HBV gene expression and replication by a direct binding to HBV transcripts or indirectly targeting host factors. The present review will discuss the role of miRNAs in the pathogenesis of HBV-related diseases and their role as a biomarker in the management of patients with HBV-related disease and as therapeutic targets.

Clinical significance of microRNA-21 expression in disease progression of patients with hepatocellular carcinoma

AIM

Aberrant microRNA (miR) expression is associated with hepatocellular carcinoma (HCC).

MATERIALS & METHODS

Here, we investigated the clinical significance of miR-21 and miR-31 for HCC-specific prognostic effect. HCC patients (n = 93) who underwent liver biopsy or surgical resection were enrolled, and HCC tissues and paired adjacent nontumor liver tissues were collected and analyzed for miRs expression.

RESULTS

MiR-21 expression was significantly upregulated in HCC tissues relative to nontumor tissues. Both miR-21 and miR-31 expression in HCC tissues did not predict overall survival; however, miR-21 was considered an independent predictor of disease progression together with portal vein thrombosis and higher Barcelona Clinical Liver Cancer stage.

CONCLUSION

Elevated miR-21 expression might represent a biomarker for HCC prognosis.

The microRNA miR-192/215 family is upregulated in mucinous ovarian carcinomas

Different microRNAs are dysregulated in ovarian cancer where some of them have proved to be valid biomarkers. miRNA profiling analyses have shown that the different histotypes of ovarian carcinoma display differential expression of specific miRNAs. In the present study, we used miRNA-sequencing and Real-Time qPCR to detect the expression levels of miRNAs belonging to the miRNA-192/215 family, namely miR-192, miR-194, and miR-215, in different types of ovarian neoplasia, finding that miR-192, miR-194, and miR-215 were upregulated in ovarian carcinomas of the mucinous subtype, but downregulated in other types of carcinoma and in sex cord-stromal tumors. The expression of the said miRNAs was 6-fold higher in mucinous tumors compared to the other histotypes making them candidates for a possible role as diagnostic biomarkers.

Transcriptional regulation of metabolism in disease: From transcription factors to epigenetics

Every cell in an individual has largely the same genomic sequence and yet cells in different tissues can present widely different phenotypes. This variation arises because each cell expresses a specific subset of genomic instructions. Control over which instructions, or genes, are expressed is largely controlled by transcriptional regulatory pathways. Each cell must assimilate a huge amount of environmental input, and thus it is of no surprise that transcription is regulated by many intertwining mechanisms. This large regulatory landscape means there are ample possibilities for problems to arise, which in a medical context means the development of disease states. Metabolism within the cell, and more broadly, affects and is affected by transcriptional regulation. Metabolism can therefore contribute to improper transcriptional programming, or pathogenic metabolism can be the result of transcriptional dysregulation. Here, we discuss the established and emerging mechanisms for controling transcription and how they affect metabolism in the context of pathogenesis. Cis- and trans-regulatory elements, microRNA and epigenetic mechanisms such as DNA and histone methylation, all have input into what genes are transcribed. Each has also been implicated in diseases such as metabolic syndrome, various forms of diabetes, and cancer. In this review, we discuss the current understanding of these areas and highlight some natural models that may inspire future therapeutics.

MIR21 Drives Resistance to Heat Shock Protein 90 Inhibition in Cholangiocarcinoma

BACKGROUND & AIMS

Cholangiocarcinomas (CCA) are resistant to chemotherapy, so new therapeutic agents are needed. We performed a screen to identify small-molecule compounds that are active against CCAs. Levels of microRNA 21 (MIR21 or miRNA21) are increased in CCAs. We investigated whether miRNA21 mediates resistance of CCA cells and organoids to HSP90 inhibitors.

METHODS

We performed a high-throughput screen of 484 small-molecule compounds to identify those that reduced viability of 6 human CCA cell lines. We tested the effects of HSP90 inhibitors on cells with disruption of the MIR21 gene, cells incubated with MIR21 inhibitors, and stable cell lines with inducible expression of MIR21. We obtained CCA biopsies from patients, cultured them as organoids (patient-derived organoids). We assessed their architecture, mutation and gene expression patterns, response to compounds in culture, and when grown as subcutaneous xenograft tumors in mice.

RESULTS

Cells with IDH1 and PBRM1 mutations had the highest level of sensitivity to histone deacetylase inhibitors. HSP90 inhibitors were effective in all cell lines, irrespective of mutations. Sensitivity of cells to HSP90 inhibitors correlated inversely with baseline level of MIR21. Disruption of MIR21 increased cell sensitivity to HSP90 inhibitors. CCA cells that expressed transgenic MIR21 were more resistant to HSP90 inhibitors than cells transfected with control vectors; inactivation of MIR21 in these cells restored sensitivity to these agents. MIR21 was shown to target the DnaJ heat shock protein family (Hsp40) member B5 (DNAJB5). Transgenic expression of DNAJB5 in CCA cells that overexpressed MIR21 re-sensitized them to HSP90 inhibitors. Sensitivity of patient-derived organoids to HSP90 inhibitors, in culture and when grown as xenograft tumors in mice, depended on expression of miRNA21.

CONCLUSIONS

miRNA21 appears to mediate resistance of CCA cells to HSP90 inhibitors by reducing levels of DNAJB5. HSP90 inhibitors might be developed for the treatment of CCA and miRNA21 might be a marker of sensitivity to these agents.

EGR1 mediates miR-203a suppress the hepatocellular carcinoma cells progression by targeting HOXD3 through EGFR signaling pathway

EGR1 plays a critical role in cancer progression. However, its precise role in hepatocellular carcinoma has not been elucidated. In this study, we found that the overexpression of EGR1 suppresses hepatocellular carcinoma cell proliferation and increases cell apoptosis by binding to the miR-203a promoter sequence. In addition, we investigated the function of miR-203a on progression of HCC cells. We verified that the effect of overexpression of miR-203a is consistent with that of EGR1 in regulation of cell progression. Through bioinformatic analysis and luciferase assays, we confirmed that miR-203a targets HOXD3. Silencing HOXD3 could block transition of the G2/M phase, increase cell apoptosis, decrease the expression of cell cycle and apoptosis-related proteins, EGFR, p-AKT, p-ERK, CCNB1, CDK1 and Bcl2 by targeting EGFR through EGFR/AKT and ERK cell signaling pathways. Likewise, restoration of HOXD3 counteracted the effects of miR-203a expression.In conclusion, our findings are the first to demonstrate that EGR1 is a key player in the transcriptional control of miR-203a, and that miR-203a acts as an anti-oncogene to suppress HCC tumorigenesis by targeting HOXD3 through EGFR-related cell signaling pathways.

Long Noncoding RNAs as a Key Player in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a major malignancy in the liver and has emerged as one of the main cancers in the world with a high mortality rate. However, the molecular mechanisms of HCC are still poorly understood. Long noncoding RNAs (lncRNAs) have recently come to the forefront as functional non-protein-coding RNAs that are involved in a variety of cellular processes ranging from maintaining the structural integrity of chromosomes to gene expression regulation in a spatiotemporal manner. Many recent studies have reported the involvement of lncRNAs in HCC which has led to a better understanding of the underlying molecular mechanisms operating in HCC. Long noncoding RNAs have been shown to regulate development and progression of HCC, and thus, lncRNAs have both diagnostic and therapeutic potentials. In this review, we present an overview of the lncRNAs involved in different stages of HCC and their potential in clinical applications which have been studied so far.

miR-20a Regulates FAS Expression in Osteosarcoma Cells by Modulating FAS Promoter Activity and Can be Therapeutically Targeted to Inhibit Lung Metastases

The metastatic potential of osteosarcoma cells is inversely correlated to cell surface FAS expression. Downregulation of FAS allows osteosarcoma cells to escape FAS ligand-mediated apoptosis when they enter a FAS ligand-positive microenvironment such as the lung. We have previously demonstrated that miR-20a, encoded by the miR-17-92 cluster, downregulates FAS expression in osteosarcoma. We further demonstrated an inverse correlation between FAS expression and miR-20a expression. However, the mechanism of FAS regulation by miR-20a was still unclear. The purpose of the current study was to evaluate the mechanism of FAS regulation by miR-20a in vitro and test the effect of targeting miR-20a in vivo We investigated whether miR-20a's downregulation of FAS was mediated by binding to the 3'-untranslated region (3'-UTR) of FAS mRNA with the consequent induction of mRNA degradation or translational suppression. We identified and mutated two miR-20a binding sites on the FAS mRNA 3'-UTR. Using luciferase reporter assays, we demonstrated that miR-20a did not bind to either the wild-type or mutated FAS 3'-UTR. In contrast, overexpression of miR-20a resulted in downregulation of FAS promoter activity. Similarly, the inhibition of miR-20a increased FAS promoter activity. The critical region identified on the FAS promoter was between -240 bp and -150 bp. Delivery of anti-miR-20a in vivo using nanoparticles in mice with established osteosarcoma lung metastases resulted in upregulation of FAS and tumor growth inhibition. Taken together, our data suggest that miR-20a regulates FAS expression through the modulation of the FAS promoter and that targeting miR-20a using anti-miR-20a has therapeutic potential. Mol Cancer Ther; 17(1); 130-9. ©2017 AACR.

Systems biology analysis of hepatitis C virus infection reveals the role of copy number increases in regions of chromosome 1q in hepatocellular carcinoma metabolism

Hepatitis C virus (HCV) infection is a worldwide healthcare problem; however, traditional treatment methods have failed to cure all patients, and HCV has developed resistance to new drugs. Systems biology-based analyses could play an important role in the holistic analysis of the impact of HCV on hepatocellular metabolism. Here, we integrated HCV assembly reactions with a genome-scale hepatocyte metabolic model to identify metabolic targets for HCV assembly and metabolic alterations that occur between different HCV progression states (cirrhosis, dysplastic nodule, and early and advanced hepatocellular carcinoma (HCC)) and healthy liver tissue. We found that diacylglycerolipids were essential for HCV assembly. In addition, the metabolism of keratan sulfate and chondroitin sulfate was significantly changed in the cirrhosis stage, whereas the metabolism of acyl-carnitine was significantly changed in the dysplastic nodule and early HCC stages. Our results explained the role of the upregulated expression of BCAT1, PLOD3 and six other methyltransferase genes involved in carnitine biosynthesis and S-adenosylmethionine metabolism in the early and advanced HCC stages. Moreover, GNPAT and BCAP31 expression was upregulated in the early and advanced HCC stages and could lead to increased acyl-CoA consumption. By integrating our results with copy number variation analyses, we observed that GNPAT, PPOX and five of the methyltransferase genes (ASH1L, METTL13, SMYD2, TARBP1 and SMYD3), which are all located on chromosome 1q, had increased copy numbers in the cancer samples relative to the normal samples. Finally, we confirmed our predictions with the results of metabolomics studies and proposed that inhibiting the identified targets has the potential to provide an effective treatment strategy for HCV-associated liver disorders.

Wnt signalling modulates transcribed-ultraconserved regions in hepatobiliary cancers

OBJECTIVE

Transcribed-ultraconserved regions (T-UCR) are long non-coding RNAs which are conserved across species and are involved in carcinogenesis. We studied T-UCRs downstream of the Wnt/β-catenin pathway in liver cancer.

DESIGN

Hypomorphic Apc mice (Apcfl/fl) and thiocetamide (TAA)-treated rats developed Wnt/β-catenin dependent hepatocarcinoma (HCC) and cholangiocarcinoma (CCA), respectively. T-UCR expression was assessed by microarray, real-time PCR and in situ hybridisation.

RESULTS

Overexpression of the T-UCR uc.158- could differentiate Wnt/β-catenin dependent HCC from normal liver and from β-catenin negative diethylnitrosamine (DEN)-induced HCC. uc.158- was overexpressed in human HepG2 versus Huh7 cells in line with activation of the Wnt pathway. In vitro modulation of β-catenin altered uc.158- expression in human malignant hepatocytes. uc.158- expression was increased in CTNNB1-mutated human HCCs compared with non-mutated human HCCs, and in human HCC with nuclear localisation of β-catenin. uc.158- was increased in TAA rat CCA and reduced after treatment with Wnt/β-catenin inhibitors. uc.158- expression was negative in human normal liver and biliary epithelia, while it was increased in human CCA in two different cohorts. Locked nucleic acid-mediated inhibition of uc.158- reduced anchorage cell growth, 3D-spheroid formation and spheroid-based cell migration, and increased apoptosis in HepG2 and SW1 cells. miR-193b was predicted to have binding sites within the uc.158- sequence. Modulation of uc.158- changed miR-193b expression in human malignant hepatocytes. Co-transfection of uc.158- inhibitor and anti-miR-193b rescued the effect of uc.158- inhibition on cell viability.

CONCLUSIONS

We showed that uc.158- is activated by the Wnt pathway in liver cancers and drives their growth. Thus, it may represent a promising target for the development of novel therapeutics.

LAMC1 mRNA promotes malignancy of hepatocellular carcinoma cells by competing for MicroRNA-124 binding with CD151

Specific RNAs can function as sinks for endogenous miRNAs, known as competing endogenous RNAs (ceRNAs). Here, we confirm a miR-124 mediated ceRNA crosstalk between LAMC1 and CD151 in hepatocellular carcinoma (HCC). miR-124 negatively regulates LAMC1 expression through two miRNA binding sites within its 3' untranslated region (3'UTR) and suppresses migration and invasion of HCC cells through regulating LAMC1. The wild type LAMC1 miRNA response elements (MREs) facilitate expression of CD151, and this regulation is miR-124 dependent. In clinical hepatic tissues, LAMC1 and CD151 mRNAs exhibit positive correlation. Importantly, LAMC1 MREs promote HCC malignancy by absorbing miR-124 and by assisting CD151 expression. We conclude that LAMC1 mRNA acts as a trans regulator to stimulate CD151 expression by competing for miR-124 binding in HCC cells. © 2017 IUBMB Life, 69(8):595-605, 2017.

miR-221 regulates CD44 in hepatocellular carcinoma through the PI3K-AKT-mTOR pathway

CD44 and miR-221 are upregulated in hepatocellular carcinoma (HCC) cell lines and tumors, however a connection between the two has not been identified. As the expression of miR-221 directly correlated with CD44 in HCC cells, we hypothesized that miR-221 may directly or indirectly regulate CD44 expression. Inhibition of miR-221 with antisense in Sk-Hep-1 or SNU-449 cell lines reduced CD44 protein expression while miR-221 mimic increased CD44 protein levels. miR-221 antisense did not alter the CD44 mRNA levels in Sk-Hep-1 or SNU-449 cells suggesting that regulation of CD44 protein occurs post transcriptionally. To discover miRNAs that may be involved in the miR-221 regulation of CD44, we performed miRNA profiling in SNU-449 cells treated with anti-miR-221. Several miRNAs were increased with miR-221 inhibition including miR-708-5p, a miRNA that targets CD44. As miR-221 targets several regulators of the PI3K-AKT-mTOR pathway and a link between this pathway and CD44 has been previously shown in prostate cancer, we considered miR-221 regulation of CD44 may be through this pathway. Inhibition of miR-221 reduced p-4EBP1, a downstream effector of the PI3K-AKT-mTOR pathway. Likewise, inhibiting the PI3K-AKT-mTOR pathway with the ATP-competitive mTOR inhibitor PP242 reduced CD44 protein in SNU-423 and SNU-449 cells without altering CD44 mRNA levels.

Regulatory role of miR-211-5p in hepatocellular carcinoma metastasis by targeting ZEB2

Hepatocellular carcinoma (HCC) is the most common type of cancer and the rapid tumor growth, drug resistance and metastasis are the major problems for HCC therapy. MicroRNAs (miRNAs) involve in various cell biological processes in HCC. ZEB2 plays crucial roles in HCC progression. ZEB2 is regulated by some identified miRNAs, but there needs to find new miRNAs regulating ZEB2 expression for better understanding the molecular mechanism of HCC. In the present study, ZEB2 was identified as a direct target of miR-211-5p, which was a potential oncogene in cancer. We found that miR-211-5p levels in HCC tissues were lower than the compared normal tissues. ZEB2 expression was higher in HCC tissues and was negatively related to miR-211-5p levels. Overexpression of miR-211-5p in human HCC cell lines (HepG2 and 7721) caused the delay of cell proliferation, apoptosis and drug sensitivity. Summarily, our study demonstrates that miR-211-5p may play a suppressing role in HCC by inhibiting ZEB2 expression.

A Circulating MicroRNA Signature Capable of Assessing the Risk of Hepatocellular Carcinoma in Cirrhotic Patients

With the availability of potent antiviral therapies, complete suppression of hepatitis B virus (HBV) replication and total eradication of hepatitis C virus (HCV) can now be achieved. Despite these advances, hepatocellular carcinoma (HCC) still develops in a substantial proportion of cirrhotic patients, suggesting that host factors remain critical. Dysregulation of miRNAs is noted in many cancers, and circulating miRNAs can be readily assayed. In this study, we aimed to develop a circulating miRNA signature to assess the risk of HCC in cirrhotic patients. We first discovered that HBV- and HCV-related cirrhotic patients had distinguishable circulating miRNA profiles. A cohort of 330 cirrhotic patients was then compared against a cohort of 42 early HCC patients with complete remission. A score comprising 5 miRNAs and a binary etiology variable was established that was capable of differentiating between these two groups (AUC = 72.5%, P < 0.001). The 330 cirrhotic patients were further stratified into high- and low-risk groups, and all patients were longitudinally followed for 752 (11-891) days. Of them, 19 patients developed HCC. The high-risk group had significantly higher cumulative HCC incidence (P = 0.038). In summary, a circulating miRNA-based score was developed that is capable of assessing HCC risks in cirrhotic patients.

MiR-502-3P suppresses cell proliferation, migration, and invasion in hepatocellular carcinoma by targeting SET

Background/aim

Increasing evidences show that microRNAs are engaged in hepatocellular carcinoma (HCC). The aim of this study was to investigate the role of miR-502-3P in HCC and to identify its underlying mechanism.

Methods

The expression levels of miR-502-3P were assessed in multiple HCC cell lines and in liver tissues of patients with HCC. We further examined the effects of miR-502-3P on malignant behavior of HCC. The molecular target of miR-502-3P was identified using a computer algorithm and confirmed experimentally.

Results

Downregulation of miR-502-3P was found in both HCC cell lines and human samples. Overexpression of miR-502-3P dramatically inhibits HCC proliferation, metastasis, invasion, and cell adhesion. We further verify the SET as a novel and direct target of miR-502-3P in HCCs.

Conclusion

Taken together, overexpression of miR-502-3P or downregulation of SET may prove beneficial as a therapeutic strategy for HCC treatment.

Epigenetically regulated miR-449a enhances hepatitis B virus replication by targeting cAMP-responsive element binding protein 5 and modulating hepatocytes phenotype

Cellular microRNAs (miRNAs) are able to influence hepatitis B virus (HBV) replication directly by binding to HBV transcripts or indirectly by targeting cellular factors. Here, we investigate the effect of epigenetically regulated miR-449a on HBV replication and the underlying mechanisms. miR-449a expression was lower in human hepatocellular carcinoma (HCC) cells than in primary hepatocytes and could be induced by trichostatin A. Ectopic miR-449a expression in HCC cells strongly enhanced HBV replication, transcription, progeny virions secretion, and antigen expression in a dose-dependent manner. miR-449a directly targeted cAMP-responsive element binding protein 5 (CREB5), which in turn induced the expression of farnesoid X receptor α (FXRα), a transcription factor that facilitates HBV replication. CREB5 knockdown and overexpression demonstrated that it is a negative regulator of HBV replication. Additionally, miR-449a overexpression inhibited proliferation, caused cell cycle arrest, and promoted HCC cell differentiation. The results indicated that epigenetically regulated miR-449a targets CREB5 to increase FXRα expression, thereby promoting HBV replication and gene expression. Our findings provide a new understanding of the role of miRNAs in HBV replication.

Twist1-related miR-26b-5p suppresses epithelial-mesenchymal transition, migration and invasion by targeting SMAD1 in hepatocellular carcinoma

Twist1 is well known to induce epithelial-mesenchymal transition (EMT) and promote tumor metastasis. MicroRNAs (miRNAs) are involved in the EMT process and are associated with metastasis in hepatocellular carcinoma (HCC). In the present study, microRNA-26b-5p (miR-26b-5p) expression was consistently and significantly downregulated in HepG2-Twist1 HCC cell lines compared with HepG2-vector cell lines using microarrays (the HepG2-Twist1 cell line can stably express Twist1). miR-26b- 5p downregulation was directly mediated by Twist1 through binding to the promoter region of miR-26b-5p in HepG2-Twist1 cells by ChIP-seq technology. Both gain- and loss-of-function studies showed that miR-26b-5p dramatically suppressed EMT and the invasion ability of HCC cells in vitro. Using mouse models, tumors derived from miR- 26b-5p-overexpressed HCC cells exhibited a significant reduction in tumorigenicity compared with the control group. Subsequent investigation revealed that miR-26b-5p directly inhibited SMAD family member 1 (SMAD1) expression. miR-26b-5p repressed BMP4/Smad1 signaling following SMAD1 inhibition. Overexpression of SMAD1 reversed the function of miR-26b-5p. In human HCC tissues and mouse xenograft tumors, miR-26b-5p levels were inversely correlated with SMAD1 expression as well as metastasis.

CONCLUSION

miR-26b-5p suppresses Twist1-induced EMT, invasion, and metastasis of HCC cells by targeting SMAD1 and BMP4/Smad1 signaling. This suggests a promising application for miR-26b-5p in anti-HCC therapy.

ANT2 shRNA downregulates miR-19a and miR-96 through the PI3K/Akt pathway and suppresses tumor growth in hepatocellular carcinoma cells

MicroRNAs (miRNAs) are negative regulators of gene expression, and miRNA deregulation is found in various tumors. We previously reported that suppression of adenine nucleotide translocase 2 (ANT2) by short hairpin RNA (shRNA) inhibits hepatocellular carcinoma (HCC) development by rescuing miR-636 expression. However, the tumor-suppressive mechanisms of ANT2 shRNA are still poorly understood in HCC. Here, we hypothesized that miRNAs that are specifically downregulated by ANT2 shRNA might function as oncomiRs, and we investigated the roles of ANT2 shRNA-regulated miRNAs in the pathogenesis of HCC. Our data show that miR-19a and miR-96, whose expression is regulated by ANT2 suppression, were markedly upregulated in HCC cell lines and clinical samples. Ectopic expression of miR-19a and miR-96 dramatically induced the proliferation and colony formation of hepatoma cells in vitro, whereas inhibition of miR-19a and miR-96 reduced these effects. To investigate the in vivo function, we implanted miR-96-overexpressing HepG2 cells in a xenograft model and demonstrated that the increase in miR-96 promoted tumor growth. We also found that miR-19a and miR-96 inhibited expression of tissue inhibitor of metalloproteinase-2. Taken together, our results suggest that ANT2-regulated miR-19a and miR-96 play an important role in promoting the proliferation of human HCC cells, and the knockdown of ANT2 directly downregulates miR-19a and miR-96, ultimately resulting in the suppression of tumor growth.