MicroRNA-3194-3p inhibits metastasis and epithelial-mesenchymal transition of hepatocellular carcinoma by decreasing Wnt/β-catenin signaling through targeting BCL9

Epigenetic regulation of hepatocellular carcinoma progression: MicroRNAs as therapeutic, diagnostic and prognostic factors

Hepatocellular carcinoma (HCC), a significant challenge for public healthcare systems in developed Western countries including the USA, Canada, and the UK, is influenced by different risk factors including hepatitis virus infections, alcoholism, and smoking. The disruption in the balance of microRNAs (miRNAs) plays a vital function in tumorigenesis, given their function as regulators in numerous signaling networks. These miRNAs, which are mature and active in the cytoplasm, work by reducing the expression of target genes through their impact on mRNAs. MiRNAs are particularly significant in HCC as they regulate key aspects of the tumor, like proliferation and invasion. Additionally, during treatment phases such as chemotherapy and radiotherapy, the levels of miRNAs are key determinants. Pre-clinical experiments have demonstrated that altered miRNA expression contributes to HCC development, metastasis, drug resistance, and radio-resistance, highlighting related molecular pathways and processes like MMPs, EMT, apoptosis, and autophagy. Furthermore, the regulatory role of miRNAs in HCC extends beyond their immediate function, as they are also influenced by other epigenetic factors like lncRNAs and circular RNAs (circRNAs), as discussed in recent reviews. Applying these discoveries in predicting the prognosis of HCC could mark a significant advancement in the therapy of this disease.

Exosomal miR-374c-5p derived from mesenchymal stem cells suppresses epithelial-mesenchymal transition of hepatocellular carcinoma via the LIMK1-Wnt/β-catenin axis

Metastasis is a leading cause to treatment failure in hepatocellular carcinoma (HCC) patients. Exosomes act as pivotal mediators in communication between different cells and exert effects on recipient cells by delivering bioactive cargoes, such as microRNAs (miRNAs). MiRNAs function in multiple steps of HCC development, including metastasis. MiR-374c-5p was previously identified as a tumor suppressor in some malignancies, while the current knowledge of its role in HCC metastasis is still limited. Herein, miR-374c-5p was found to be downregulated in HCC cell lines and clinical samples, and positively related with favorable prognosis in HCC patients. MiR-374c-5p transferred by exosomes derived from bone marrow mesenchymal stem cell (BMSC) suppressed migration, invasion and proliferation of HCC cells. LIMK1 was verified as downstream target gene of miR-374c-5p. Knockdown of LIMK1 reduced invasion, migration and proliferation of HCC cells, whereas overexpression functioned oppositely. The miR-374c-5p/LIMK1 axis suppressed epithelial-mesenchymal transition (EMT) by inactivating Wnt/β-catenin pathway. In addition, miR-374c-5p was downregulated and LIMK1 upregulated in TGF-β1 induced EMT. This EMT model could be reversed by LIMK1 silencing or miR-374c-5p overexpression. These results suggest that exo-miR-374c-5p suppresses EMT via targeting LIMK1-Wnt/β-catenin axis and the axis is involved in TGF-β1 induced metastasis of HCC, thereby identifying miR-374c-5p as a potential target for HCC treatment.

The Role of miRNAs, circRNAs and Their Interactions in Development and Progression of Hepatocellular Carcinoma: An Insilico Approach

Hepatocellular carcinoma (HCC) is a type of malignant tumor. miRNAs are noncoding RNAs and their differential expression patterns are observed in HCC-induced by alcoholism, HBV and HCV infections. By acting as a competing endogenous RNA (ceRNA), circRNA regulates the miRNA function, indirectly controlling the gene expression and leading to HCC progression. In the present study, data mining was performed to screen out all miRNAs and circRNA involved in alcohol, HBV or HCV-induced HCC with statistically significant (≤0.05%) expression levels reported in various studies. Further, the interaction of miRNAs and circRNA was also investigated to explore their role in HCC due to various causative agents. Together, these study data provide a deeper understanding of the circRNA-miRNA regulatory mechanisms in HCC. These screened circRNA, miRNA and their interactions can be used as prognostic biomarkers or therapeutic targets for the treatment of HCC.

Recent progress in molecular mechanisms of postoperative recurrence and metastasis of hepatocellular carcinoma

Hepatectomy is currently considered the most effective option for treating patients with early and intermediate hepatocellular carcinoma (HCC). Unfortunately, the postoperative prognosis of patients with HCC remains unsatisfactory, predominantly because of high postoperative metastasis and recurrence rates. Therefore, research on the molecular mechanisms of postoperative HCC metastasis and recurrence will help develop effective intervention measures to prevent or delay HCC metastasis and recurrence and to improve the long-term survival of HCC patients. Herein, we review the latest research progress on the molecular mechanisms underlying postoperative HCC metastasis and recurrence to lay a foundation for improving the understanding of HCC metastasis and recurrence and for developing more precise prevention and intervention strategies.

Retraction Note: Long non-coding RNA AGAP2-AS1, functioning as a competitive endogenous RNA, upregulates ANXA11 expression by sponging miR-16-5p and promotes proliferation and metastasis in hepatocellular carcinoma

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1186/s13046-019-1188-x.

Sirtuins and Hypoxia in EMT Control

Epithelial–mesenchymal transition (EMT), a physiological process during embryogenesis, can become pathological in the presence of different driving forces. Reduced oxygen tension or hypoxia is one of these forces, triggering a large number of molecular pathways with aberrant EMT induction, resulting in cancer and fibrosis onset. Both hypoxia-induced factors, HIF-1α and HIF-2α, act as master transcription factors implicated in EMT. On the other hand, hypoxia-dependent HIF-independent EMT has also been described. Recently, a new class of seven proteins with deacylase activity, called sirtuins, have been implicated in the control of both hypoxia responses, HIF-1α and HIF-2α activation, as well as EMT induction. Intriguingly, different sirtuins have different effects on hypoxia and EMT, acting as either activators or inhibitors, depending on the tissue and cell type. Interestingly, sirtuins and HIF can be activated or inhibited with natural or synthetic molecules. Moreover, recent studies have shown that these natural or synthetic molecules can be better conveyed using nanoparticles, representing a valid strategy for EMT modulation. The following review, by detailing the aspects listed above, summarizes the interplay between hypoxia, sirtuins, and EMT, as well as the possible strategies to modulate them by using a nanoparticle-based approach.

Non-coding RNAs regulating epithelial-mesenchymal transition: Research progress in liver disease

Chronic liver injury could gradually progress to liver fibrosis, cirrhosis, and even hepatic carcinoma without effective treatment. The massive production and activation of abnormal cell differentiation is vital to the procession of liver diseases. Epithelial-mesenchymal transformation (EMT) is a biological process in which differentiated epithelial cells lose their epithelial characteristics and acquire mesenchymal cell migration capacity. Emerging evidence suggests that EMT not only occurs in the process of hepatocellular carcinogenesis, but also appears in liver cells transforming to myofibroblasts, a core event of liver disease. Non-coding RNA (ncRNA) such as microRNA (miRNA), long non-coding RNA (lncRNA) and circular RNA (circRNA) are important regulatory factors in EMT, which can regulate target gene expression by binding with RNA single-stranded. Various studies had shown that ncRNA regulation of EMT plays a key role in liver disease development, and many effective ncRNAs have been identified as promising biomarkers for the diagnosis and treatment of liver disease. In this review, we focus on the relationship between the different ncRNAs and EMT as well as the specific molecular mechanism in the liver diseases to enrich the pathological progress of liver diseases and provide reference for the treatment of liver diseases.

Circular RNA SOX13 promotes malignant behavior and cisplatin resistance in non-small cell lung cancer through targeting microRNA-3194-3p/microtubule-associated protein RP/EB family member 1

Circular RNA (circRNA) presents an essential regulatory role in affecting the occurrence and acquired resistance in non-small cell lung cancer (NSCLC), but how circSOX13 impacts NSCLC is unclear. In this work it was found that compared with adjacent normal tissues, circSOX13 and the microtubule-associated protein RP/EB family member 1 (MAPRE1) were signally up-regulated in NSCLC while miR-3194-3p was signally lowered. Pulmonary function tests (PETs) revealed that knocking down circSOX13 or overexpressing miR-3194-3p inhibited NSCLC proliferation, invasion and migration but promoted its apoptosis. The promoting effect of overexpressing circSOX13 on NSCLC was reversed via knocking down MAPRE1. Additionally, knocking down circSOX13 reduced cisplatin resistance in NSCLC. Furthermore, circSOX13 mediated MAPRE1 expression via competitively binding miR-3194-3p to exert its tumorigenic impact. To conclude, this work clarified the carcinogenic impact of circSOX13-miR-3194-3p-MAPRE1 axis on NSCLC and DDP resistance. CircSOX13 can be a potential diagnostic marker and therapeutic target for NSCLC, thus providing a new insight for clinically reversing its acquired resistance.

Wnt Signaling Pathway Is among the Drivers of Liver Metastasis

Liver metastasis, originating either from a primary liver or other cancer types, represent a large cancer-related burden. Therefore, studies that add to better understanding of its molecular basis are needed. Herein, the role of the Wnt signaling pathway in liver metastasis is outlined. Its role in hepatocellular carcinoma (HCC) epithelial-mesenchymal transition (EMT), motility, migration, metastasis formation, and other steps of the metastatic cascade are presented. Additionally, the roles of the Wnt signaling pathway in the liver metastasis formation of colorectal, breast, gastric, lung, melanoma, pancreatic, and prostate cancer are explored. The special emphasis is given to the role of the Wnt signaling pathway in the communication between the many of the components of the primary and secondary cancer microenvironment that contribute to the metastatic outgrowth in the liver. The data presented herein are a review of the most recent publications and advances in the field that add to the idea that the Wnt pathway is among the drivers of liver metastasis and that its targeting could potentially relieve liver metastasis–related complications.

Long noncoding RNA KCNMB2-AS1 promotes the development of esophageal cancer by modulating the miR-3194-3p/PYGL axis

Esophageal cancer (ESCA), as a common cancer worldwide, is a main cause of cancer-related mortality. Comprehensive studies on molecular mechanism of ESCA have been carried out. Though numerous long noncoding RNAs (lncRNAs) was reported to participate in the occurrence and development of ESCA, the potential role of lncRNA potassium calcium-activated channel subfamily M regulatory beta subunit 2 (KCNMB2) antisense RNA 1 (KCNMB2-AS1) in ESCA remains to be discovered. This study intends to investigate the detailed function and molecular mechanism of KCNMB2-AS1 in ESCA. Gene expression was evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Cell proliferation was examined by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Cell invasion and migration were measured by wound healing assay and Transwell assay. Luciferase reporter assay was adopted to validate the interaction between KCNMB2-AS1 and miR-3194-3p. Western blotting was performed to assess protein levels. We discovered that KCNMB2-AS1 was significantly upregulated in ESCA. KCNMB2-AS1 downregulation suppressed the growth, invasion, migration and stemness of ESCA cells. KCNMB2-AS1 bound with miR-3194-3p, and glycogen phosphorylase L (PYGL) was a direct target of miR-3194-3p. KCNMB2-AS1 upregulated PYGL expression by directly binding with miR-3194-3p. Additionally, PYGL overexpression abolished the inhibitory influence of KCNMB2-AS1 depletion on ESCA cell behaviors. Collectively, lncRNA KCNMB2-AS1 promotes ESCA development through targeting the miR-3194-3p/ PYGL axis, which might provide theoretical basis to explore novel biomarkers for ESCA treatment.

Interplay between SOX9 transcription factor and microRNAs in cancer

SOX transcription factors are critical regulators of development, homeostasis and disease progression and their dysregulation is a common finding in various cancers. SOX9 belongs to SOXE family located on chromosome 17. MicroRNAs (miRNAs) possess the capacity of regulating different transcription factors in cancer cells by binding to 3'-UTR. Since miRNAs can affect differentiation, migration, proliferation and other physiological mechanisms, disturbances in their expression have been associated with cancer development. In this review, we evaluate the relationship between miRNAs and SOX9 in different cancers to reveal how this interaction can affect proliferation, metastasis and therapy response of cancer cells. The tumor-suppressor miRNAs can decrease the expression of SOX9 by binding to the 3'-UTR of mRNAs. Furthermore, the expression of downstream targets of SOX9, such as c-Myc, Wnt, PI3K/Akt can be affected by miRNAs. It is noteworthy that other non-coding RNAs including lncRNAs and circRNAs regulate miRNA/SOX9 expression to promote/inhibit cancer progression and malignancy. The pre-clinical findings can be applied as biomarkers for diagnosis and prognosis of cancer patients.

Role of Wnt/β-catenin signaling pathway in occurrence and development of hepatocellular carcinoma

Studies have shown that the occurrence and development of liver cancer are related to a variety of signaling pathways. The Wnt/β-catenin signaling pathway is involved in all stages of liver disease progression, from initial liver damage to inflammation, fibrosis, and cirrhosis, as well as the occurrence and progression of tumors. Abnormal Wnt/β-catenin signaling promotes the development and progression of different liver diseases, including cancer. This review introduces the activation, biological function, and regulatory mechanism of the Wnt/β-catenin signaling pathway, discusses the role of ngthis pathway in the occurrence and progression of liver cancer, and describes factors that can inhibit the Wnt/β-catenin signaling pathway, such as small molecule inhibitors, traditional Chinese medicine extracts, and microRNAs, with an aim to provide reference for the basic and clinical research of liver cancer.

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.

Long noncoding RNA PICSAR/miR-588/EIF6 axis regulates tumorigenesis of hepatocellular carcinoma by activating PI3K/AKT/mTOR signaling pathway

Accumulating evidence has identified long noncoding RNAs (lncRNAs) as regulators in tumor progression and development. Here, we elucidated the function and possible molecular mechanisms of the effect of lncRNA-PICSAR (p38 inhibited cutaneous squamous cell carcinoma associated lincRNA) on the biological behaviors of HCC. In the present study, we found that PICSAR was upregulated in HCC tissues and cells and correlated with progression and poor prognosis in HCC patients. Gain- and loss-of-function experiments indicated that PICSAR enhanced cell proliferation, colony formation, and cell cycle progression and inhibited apoptosis of HCC cells. PICSAR could function as a competing endogenous RNA by sponging microRNA (miR)-588 in HCC cells. Mechanically, miR-588 inhibited HCC progression and alternation of miR-588 reversed the promotive effects of PICSAR on HCC cells. In addition, we confirmed that eukaryotic initiation factor 6 (EIF6) was a direct target of miR-588 in HCC and mediated the biological effects of miR-588 and PICSAR in HCC, resulting in PI3K/AKT/mTOR pathway activation. Our data identified PICSAR as a novel oncogenic lncRNA associated with malignant clinical outcomes in HCC patients. PICSAR played an oncogenic role by targeting miR-588 and subsequently promoted EIF6 expression and PI3K/AKT/mTOR activation in HCC. Our results revealed that PICSAR could be a potential prognostic biomarker and therapeutic target for HCC.

Hypoxia-induced epithelial to mesenchymal transition in cancer

A common feature of many solid tumors is low oxygen conditions due to inadequate blood supply. Hypoxia induces hypoxia inducible factor (HIF) stabilization and downstream signaling. This signaling has pleiotropic roles in cancers, including the promotion of cellular proliferation, changes in metabolism, and induction of angiogenesis. In addition, hypoxia is becoming recognized as an important driver of epithelial-to-mesenchymal (EMT) in cancer. During EMT, epithelial cells lose their typical polarized states and transition to a more mobile mesenchymal phenotype. Hypoxia induces this transition by modulating EMT signaling pathways, inducing EMT transcription factor activity, and regulating miRNA networks. As both hypoxia and EMT modulate the tumor microenvironment (TME) and are associated with immunosuppression, we also explore how these pathways may impact response to immuno-oncology therapeutics.

MicroRNA‑875‑5p inhibits tumor growth and metastasis of hepatocellular carcinoma by targeting eukaryotic translation initiation factor 3 subunit a

Accumulating evidence has demonstrated that aberrant microRNA (miRNA) expression is involved in hepatocellular carcinoma (HCC) progression. Previous findings suggested that miRNA (miR)‑875‑5p participates in the development of various types of cancer. However, the expression and function of miR‑875‑5p in HCC remains largely unclear. The analysis of clinical samples in the present study demonstrated that miR‑875‑5p expression was downregulated in HCC tissues compared to adjacent non‑tumor tissues, which was associated with a large tumor size, venous infiltration, advanced tumor‑node‑metastasis stage and unfavorable overall survival. In vitro experiments revealed that ectopic expression of miR‑875‑5p suppressed, whereas inhibition of miR‑875‑5p promoted HCC cell proliferation, migration, invasion and epithelial‑to‑mesenchymal transition (EMT) progression. Overexpression of miR‑875‑5p restrained HCC tumor growth and metastasis in vivo. Mechanistically, eukaryotic translation initiation factor 3 subunit a (eIF3a) was identified as the downstream target of miR‑875‑5p in HCC. Further experiments demonstrated that the expression of eIF3a was upregulated and negatively correlated with that of miR‑875‑5p in HCC tissues. In addition, miR‑875‑5p negatively regulated the luciferase activity of wild‑type, but not mutant 3'‑untranslated region (3'UTR) of eIF3a mRNA. miR‑875‑5p suppressed eIF3a expression at the mRNA and protein level in HCC cells. Additionally, eIF3a exerted an oncogenic role, and knockdown of eIF3a inhibited the proliferation, motility and EMT of HCC cells. In addition, eIF3a overexpression abolished the inhibitory effects of miR‑875‑5p on the proliferation, motility and EMT in HCC cells. In conclusion, miR‑875‑5p, which was downregulated in HCC, may inhibit tumor growth and metastasis by eIF3a downregulation via targeting its 3'UTR and may be a promising prognostic and therapeutic strategy in HCC.

MiR-3194-3p Inhibits Breast Cancer Progression by Targeting Aquaporin1

Increasing evidence indicates that the Aquaporin1 (AQP1) aberrant expression may be related to a wide variety of human cancers, including breast cancer (BC). In the present study, we explore the effects and possible mechanism of miR-3194-3p on the biological behaviors of BC. At first, miR-3194-3p is found to modulate AQP1 expression targeting the 3′-UTR using miRNA target prediction algorithms. MiR-3194-3p expression is markedly downregulated, and AQP1 expression is upregulated in BC tissues compared with adjacent normal breast tissues. Moreover, the differential expression of miR-3194-3p and AQP1 are observed in four BC cells with different malignancy degree. Meanwhile, a significant negative correlation between AQP1 and miR-3194-3p expressions in tumor tissues from 30 BC patients is revealed. miR-3194-3p mimic remarkably inhibits cell proliferation, migration, and invasion as well as promotes apoptosis in MDA-MB-231 cells while miR-3194-3p inhibitors exert an opposite role in MCF-7 cells. Dual-luciferase reporter system demonstrates that AQP1 is a direct target gene of miR-3194-3p. Overexpression of AQP1 by pBABE-puro-AQP1 vector partially abrogates the effect of miR-3194-3p mimic in MDA-MB-231 cells. In short, our results suggest that miR-3194-3p suppresses BC cell proliferation, migration, and invasion by targeting AQP1, providing a novel insight into BC tumorigenesis and treatment.

New Advances in Canonical Wnt/β-Catenin Signaling in Cancer

Wnt/β-catenin-mediated signaling is a key pathway regulating tissue growth and development, and tumorigenesis, and has received increasing attention in recent years. In addition to participating in healthy tissue and organ development, ectopic activation of the pathway can cause a variety of tumors and other pathologies. The pathway plays a critical role in many processes such as proliferation, differentiation, apoptosis, migration, invasion, epithelial–mesenchymal transition and cancer cell stemness. The importance of the Wnt signal is self-evident. This review describes the underlying mechanism of Wnt signaling pathway and highlights the latest findings on the relationship between Wnt signaling pathway and tumorigenesis. In addition, the potential relationship between miRNAs and Wnt signaling is presented. Furthermore, we discuss the intrinsic link between Wnt signaling and cancer cell stemness, which shed light on the malignant progression of tumor cells. Finally, cancer treatment strategies based on the canonical Wnt signaling pathway are summarized, hoping to help clinical development.

ZNF521 which is downregulated by miR-802 suppresses malignant progression of Hepatocellular Carcinoma through regulating Runx2 expression

Zinc finger protein 521 (ZNF521) plays an important role in the tumor development and process. However, its regulatory role in hepatocellular carcinoma (HCC) remains unclear. In this study, we demonstrated for the first time that ZNF521 mRNA and protein was down-regulated in HCC tissues and cell lines. Down-regulated ZNF521 expression was significantly associated with malignant prognostic features, including advanced TNM stage and large tumor size. For 5-year survival, ZNF521 served as a potential prognostic marker of HCC patients. Moreover, ZNF521 inhibited cell proliferation, colony formation and cell viability through Runx2 transcriptional inhibition and AKT phosphorylation pathway. Moreover, we demonstrated that ZNF521 expression was regulated by miR-802. In HCC tissues. MiR-802 has an inverse correlation with ZNF521 expression. In conclusion, we demonstrate for the first time that ZNF521 is down-regulated in HCC tissues and inhibits HCC growth through Runx2 transcriptional inhibition and AKT inactivation, which was regulated by miR-802, suggesting the potential therapeutic value for HCC.

ZKSCAN3 drives tumor metastasis via integrin β4/FAK/AKT mediated epithelial-mesenchymal transition in hepatocellular carcinoma

Background

ZKSCAN3, a zinc-finger transcription factor containing KRAB and SCAN domains, has been reported to be regulated in several human cancers. However, its expression and function in hepatocellular carcinoma (HCC) remains unknown.

Methods

Expression of ZKSCAN3 in HCC was analyzed by western blotting, immunohistochemistry, and real time PCR. Its correlation with the clinicopathological characteristics and prognosis of HCC patients was analyzed. The effects of ZKSCAN3 on the migration and invasion were determined by Transwell assays. The potential downstream targets of ZKSCAN3 and related molecular mechanisms were clarified by Western blot and dual luciferase reporter assay.

Results

In this study, we demonstrated for the first time that ZKSCAN3 mRNA and protein was up-regulated in HCC tissues and cell lines. High ZKSCAN3 expression was significantly associated with poor prognostic features, including advanced TNM stage and vascular invasion. For 5-year survival, ZKSCAN3 served as a potential prognostic marker of HCC patients. Functionally, ZKSCAN3 promoted migration, invasion and EMT progress via directly binding to integrin β4 (ITGB4) promoter and enhanced its expression. Further investigation proved that ITGB4 triggers the focal adhesion kinase (FAK) to activate the AKT signaling pathway. Inactivation of FAK and AKT by their specific inhibitors respectively reversed the effects of ZKSCAN3 on HCC cells. In addition, we demonstrated that ZKSCAN3 expression was regulated by miR-124. In HCC tissues. MiR-124 has an inverse correlation with ZKSCAN3 expression.

Conclusion

We demonstrate for the first time that ZKSCAN3 is overexpressed in HCC tissues and promotes migration, invasion and EMT process through ITGB4-dependent FAK/AKT activation, which was regulated by miR-124, suggesting the potential therapeutic value for HCC.

Circ_0000517 Contributes to Hepatocellular Carcinoma Progression by Upregulating TXNDC5 via Sponging miR-1296-5p

Background

Circular RNAs (circRNAs) function as essential regulators in diverse human cancers, including hepatocellular carcinoma (HCC). However, the function of circ_0000517 in HCC was unknown. We aimed to explore the roles and mechanisms of circ_0000517 in HCC.

Materials and Methods

The levels of circ_0000517, RPPH1 mRNA and microRNA-1296-5p (miR-1296-5p) were measured using quantitative real-time polymerase chain reaction (qRT-PCR). The characteristics of circ_0000517 were explored by RNase R digestion and actinomycin D assays. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8) and colony formation assays. Cell cycle process and cell apoptosis were analyzed by flow cytometry analysis. The function of circ_0000517 in vivo was explored by a murine xenograft model. The association between miR-1296-5p and circ_0000517 or thioredoxin domain containing 5 (TXNDC5) was determined by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. The protein level of TXNDC5 was detected by Western blot assay.

Results

Circ_0000517 was upregulated in HCC tissues and cells. Silencing of circ_0000517 suppressed HCC cell viability and colony formation and promoted cell cycle arrest and apoptosis in vitro and hampered tumor growth in vivo. MiR-1296-5p was a target of circ_0000517 and the effects of circ_0000517 silencing on HCC cell viability, cell cycle, colony formation and apoptosis were abolished by miR-1296-5p inhibition. TXNDC5 functioned as a target gene of miR-1296-5p, and the inhibitory effect of miR-1296-5p on HCC cell progression was rescued by TXNDC5 overexpression. Moreover, circ_0000517 promoted TXNDC5 expression via targeting miR-1296-5p.

Conclusion

Circ_0000517 accelerated HCC progression by upregulating TXNDC5 through sponging miR-1296-5p.

MicroRNA-639 is Down-Regulated in Hepatocellular Carcinoma Tumor Tissue and Inhibits Proliferation and Migration of Human Hepatocellular Carcinoma Cells Through the KAT7/Wnt/β-Catenin Pathway

Background

This study aimed to investigate the expression of microRNA-639 (miR-639) in tumor tissue from patients with hepatocellular carcinoma (HCC) and its effects on patient outcome, to identify the targets for miR-639 using bioinformatics and luciferase reporter analysis, and the effects of miR-639 in human HCC cells in vitro to identify the molecular pathways involved.

Material/Methods

Expression levels of miR-639 were compared in tumor tissue and adjacent normal liver tissue from 50 patients with HCC, and Kaplan-Meier curves identified the association with overall survival (OS). miR-639 expression was measured in HCC cells cultured in vitro using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and Western blot. HCC cells were studied using the MTT assay, the colony formation assay, and the transwell assay. Bioinformatics and luciferase reporter analysis identified the role of the histone acetyltransferase gene, KAT7, in HCC.

Results

The expression of miR-639 was significantly reduced in HCC tissues compared with normal adjacent liver tissues, and inhibited cell proliferation and epithelial-mesenchymal transition (EMT) of HCC cells. Bioinformatics and luciferase reporter analysis showed that miR-639 directly targeted KAT7 and inhibit its expression. KAT7 expression promoted cell proliferation, and migration of human HCC cells in vitro, and miR-639 inhibited cell proliferation and EMT by down-regulating the KAT7/Wnt/β-catenin signaling pathway.

Conclusions

miR-639 was down-regulated in HCC tumor tissue, and inhibited proliferation and migration of HCC cells by the down-regulation of KAT7/Wnt/β-catenin signaling and was associated with reduced OS. These findings supported the potential role of miR-639 as a tumor suppressor.