miR-186 Inhibits Liver Cancer Stem Cells Expansion via Targeting PTPN11

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.

N6-methyladenosine (m6A) modification in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the deadliest cancers of human, the tumor-related death of which ranks third among the common malignances. N6-methyladenosine (m6A) methylation, the most abundant internal modification of RNA in mammals, participates in the metabolism of mRNA and interrelates with ncRNAs. In this paper, we overviewed the complex function of m6A regulators in HCC, including regulating the tumorigenesis, progression, prognosis, stemness, metabolic reprogramming, autophagy, ferroptosis, drug resistance and tumor immune microenvironment (TIME). Furthermore, we elucidated the interplay between m6A modification and non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs). Finally, we summarized the potential of m6A regulators as diagnostic biomarkers. What's more, we reviewed the inhibitors targeting m6A enzymes as promising therapeutic targets of HCC. We aimed to help understand the function of m6A methylation in HCC systematically and comprehensively so that more effective strategies for HCC treatment will be developed.

Splicing factor ESRP1 derived circ_0068162 promotes the progression of oral squamous cell carcinoma via the miR-186/JAG axis

OBJECTIVES

Oral squamous cell carcinoma (OSCC) is a common malignancy in the oral and maxillofacial regions with an increasing incidence rate. Circular RNA (circRNA) is a recently discovered long-chain non-coding RNA family member. The objective of this study was to analyze the role of circ_0068162 in OSCC development.

METHODS

We downloaded sample data GSE145608 from the Gene Expression Omnibus database. Online databases Starbase, TargetScan and miRDB were used to predict the target microRNAs (miRNAs) and genes. Cell viability and proliferation were assessed using the CCK-8 and EdU assays, respectively. Cell migration and invasion abilities were detected using transwell assay. The double luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to verify the interaction relationship between the identified target molecules. RNase R and actinomycin D treatment were performed to analyze the stability of circ_0068162.

RESULTS

We found that circ_0068162 was overexpressed in the cytoplasm of OSCC cells and clinical OSCC tissues. Knockdown of circ_0068162 inhibited the growth, migration and invasion of OSCC cells. We also identified miR-186 as the target miRNA of circ_0068162, and JAG1 and JAG2 as the target genes of miR-186. The miR-186 inhibitor rescued the effects of sh-circ_0068162 and JAG1/JAG2 overexpression rescued the effects of miR-186 mimic in OSCC cells. Furthermore, ESRP1 promoted the biosynthesis of circ_0068162.

CONCLUSIONS

The circ_0068162/miR-186/JAGs/ESRP1 feedback loop is closely related to OSCC development.

Identification of the key genes and mechanisms associated with transcatheter arterial chemoembolisation refractoriness in hepatocellular carcinoma

BACKGROUND

Transcatheter arterial embolisation (TACE) is the primary treatment for intermediate-stage hepatocellular carcinoma (HCC) patients while some HCC cases have shown resistance to TACE.

AIM

To investigate the key genes and potential mechanisms correlated with TACE refractoriness in HCC.

METHODS

The microarray datasets of TACE-treated HCC tissues, HCC and non-HCC tissues were collected by searching multiple public databases. The respective differentially expressed genes (DEGs) were attained via limma R package. Weighted gene co-expression network analysis was employed for identifying the significant modules related to TACE non-response. TACE refractoriness-related genes were obtained by intersecting up-regulated TACE-associated and HCC-associated DEGs together with the genes in significant modules related to TACE non-response. The key genes expression in the above two pairs of samples was compared respectively via Wilcoxon tests and standard mean differences model. The prognostic value of the key genes was evaluated by Kaplan-Meier curve. Multivariate analysis was utilised to investigate the independent prognostic factor in key genes. Single-cell RNA (scRNA) sequencing analysis was conducted to explore the cell types in HCC. TACE refractoriness-related genes activity was calculated via AUCell packages. The CellChat R package was used for the investigation of the cell-cell communication between the identified cell types.

RESULTS

HCC tissues of TACE non-responders (n = 66) and TACE responders (n = 81), HCC (n = 3941) and non-HCC (n = 3443) tissues were obtained. The five key genes, DLG associated protein 5 (DLGAP5), Kinesin family member 20A (KIF20A), Assembly factor for spindle microtubules (ASPM), Kinesin family member 11 (KIF11) and TPX2 microtubule nucleation factor (TPX2) in TACE refractoriness-related genes, were identified. The five key genes were all up-regulated in the TACE non-responders group and the HCC group. High expression of the five key genes predicted poor prognosis in HCC. Among the key genes, TPX2 was an independent prognostic factor. Four cell types, hepatocytes, embryonic stem cells, T cells and B cells, were identified in the HCC tissues. The TACE refractoriness-related genes expressed primarily in hepatocytes and embryonic stem cells. Hepatocytes, as the providers of ligands, had the strongest interaction with embryonic stem cells that provided receptors.

CONCLUSION

Five key genes (DLGAP5, KIF20A, ASPM, KIF11 and TPX2) were identified as promoting refractory TACE. Hepatocytes and embryonic stem cells were likely to boost TACE refractoriness.

LncRNA FOXD1-AS1 regulates pancreatic cancer stem cell properties and 5-FU resistance by regulating the miR-570-3p/SPP1 axis as a ceRNA

Cancer stem cells (CSCs) play a pivotal role in the pathogenesis of human cancers. Previous studies have highlighted the role of long non-coding RNA (lncRNA) in modulating the stemness of CSCs. In our investigation, we identified an upregulation of lncRNA FOXD1-AS1 in CSCs. The enforced expression of lncRNA FOXD1-AS1 promotes tumorigenesis and self-renewal in pancreatic cancer CSCs. Conversely, the knockdown of lncRNA FOXD1-AS1 inhibits tumorigenesis and self-renewal in pancreatic cancer CSCs. Furthermore, our findings reveal that lncRNA FOXD1-AS1 enhances self-renewal and tumorigenesis in pancreatic cancer CSCs by up-regulating osteopontin/secreted phosphoprotein 1(SPP1) and acting as a ceRNA to sponge miR-570-3p in pancreatic cancer (PC) CSCs. Additionally, lncRNA FOXD1-AS1 depleted pancreatic cancer cells exhibit heightened sensitivity to 5-FU-indued cell growth inhibition and apoptosis. Analysis of patient-derived xenografts (PDX) indicates that a low level of lncRNA FOXD1-AS1 may serve as a predictor of 5-FU benefits in PC patients. Moreover, the introduction of SPP1 can reverse the sensitivity of lncRNA FOXD1-AS1-knockdown PC cells to 5-FU-induced cell apoptosis. Importantly, molecular studies have indicated that the elevated levels of lncRNAFOXD1-AS1 in PC are facilitated through METTL3 and YTHDF1-dependent m6A methylation. In summary, our results underscore the critical functions of lncRNA FOXD1-AS1 in the self-renewal and tumorigenesis of pancreatic cancer CSCs, positioning lncRNA FOXD1-AS1 as a promising therapeutic target for PC.

miR-186 regulates epithelial-mesenchymal transformation to promote nasopharyngeal carcinoma metastasis by targeting ZEB1

OBJECTIVES

Nasopharyngeal carcinoma (NPC) is an aggressive epithelial cancer. The expression of miR-186 is decreased in a variety of malignancies and can promote the invasion and metastasis of cancer cells. This study aimed to explore the role and possible mechanism of miR-186 in the metastasis and epithelial-mesenchymal transformation (EMT) of NPC.

METHODS

The expression of miR-186 in NPC tissues and cells was detected by RT-PCR. Then, miR-186 mimic was used to transfect NPC cell lines C666-1 and CNE-2, and cell activity, invasion and migration were detected by CCK8, transwell and scratch assay, respectively. The expression of EMT-related proteins was analyzed by western blotting analysis. The binding relationship between miR-186 and target gene Zinc Finger E-Box Binding Homeobox 1 (ZEB1) was confirmed by double luciferase assay.

RESULTS

The expression of miR-186 in NPC was significantly decreased, and transfection of miR-186 mimic could significantly inhibit the cell activity, invasion, and migration, and regulate the protein expressions of E-cadherin, N-cadherin and vimentin in C666-1 and CNE-2 cells. Further experiments confirmed that miR-186 could directly target ZEB1 and negatively regulate its expression. In addition, ZEB1 has been confirmed to be highly expressed in NPC, and inhibition of ZEB1 could inhibit the activity, invasion, metastasis and EMT of NPC cells. And co-transfection of miR-186 mimic and si-ZEB1 could further inhibit the proliferation and metastasis of NPC.

CONCLUSION

miR-186 may inhibit the proliferation, metastasis and EMT of NPC by targeting ZEB1, and the miR-186/ZEB1 axis plays an important role in NPC.

miRNA-381 regulates renal cancer stem cell properties and sunitinib resistance via targeting SOX4

Cancer stem cells (CSCs) are crucial in the pathogenesis of human cancers. Existing studies reported that microRNA (miRNA) modulates the stemness of CSCs. We discovered that renal cell CSCs have suppressed miR-381. Suppression of miR-381 promotes renal cell tumorigenesis and CSC-like properties. Furthermore, the forced expression of miR-381 prevents the renal cell tumorigenesis and CSC-like properties. Mechanistically, renal cell CSCs have been found to interact with SOX4 through miR-381 directly. miR-381 inhibits renal cell CSC-like properties and tumorigenesis via downregulating SOX4. Examination of the patient-derived xenografts (PDX) and patient cohorts reveals that miR-381 may be able to forecast the advantages of Sunitinib in RCC patients. Moreover, the introduction of SOX4 could reverse the sensitivity of miR-381 overexpression RCC cells to Sunitinib-induced cell apoptosis. These results indicated that miR-381 is critical in renal cell CSC-like properties and tumorigenesis, making it the ideal therapeutic target for RCC.

miR-552 promotes the proliferation and metastasis of intrahepatic cholangiocarcinoma by targeting FOXO1

Intrahepatic cholangiocarcinoma (ICC) is a relatively rare but highly malignant cancer. Few effective systemic targeted therapies are available for patients with unresectable ICC, but there exists an urgent need to explore mechanisms underlying the initiation and progression of ICC. MicroRNA (miRNA) plays vital roles in the initiation, progression, and drug resistance of different cancers. Recently, the biological function of a novel miRNA, miR-552, has been widely analyzed in hepatocellular carcinoma and colorectal, cervical, gastric, and other cancers. However, its role in ICC has not yet been elucidated. In this study, we found that miR-552 expression was upregulated in ICC and that miR-552 predicted poor prognosis. Using functional studies, we found that miR-552 enhanced the proliferation and invasion ability of ICC cells. Mechanistic research identified that forkhead box O1 (FOXO1) is the target of miR-552 in ICC. Moreover, the combined panels of miR-552 and FOXO1 exhibited a better prognostic value for ICC patients than did miR-552 alone. In conclusion, these findings demonstrated that the miR-552/FOXO1 axis drove ICC progression, further suggesting that targeting this axis could be a novel therapeutic strategy for ICC.

Little things with significant impact: miRNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has developed into one of the most lethal, aggressive, and malignant cancers worldwide. Although HCC treatment has improved in recent years, the incidence and lethality of HCC continue to increase yearly. Therefore, an in-depth study of the pathogenesis of HCC and the search for more reliable therapeutic targets are crucial to improving the survival quality of HCC patients. Currently, miRNAs have become one of the hotspots in life science research, which are widely present in living organisms and are non-coding RNAs involved in regulating gene expression. MiRNAs exert their biological roles by suppressing the expression of downstream genes and are engaged in various HCC-related processes, including proliferation, apoptosis, invasion, and metastasis. In addition, the expression status of miRNAs is related to the drug resistance mechanism of HCC, which has important implications for the systemic treatment of HCC. This paper reviews the regulatory role of miRNAs in the pathogenesis of HCC and the clinical applications of miRNAs in HCC in recent years.

HtrA2 Independently Predicts Poor Prognosis and Correlates with Immune Cell Infiltration in Hepatocellular Carcinoma

High-temperature requirement protein A2 (HtrA2), a mitochondrial protein, is related to apoptosis regulation. However, the role of HtrA2 in hepatocellular carcinoma (HCC) remains unclear. In the present study, we explored the prognostic value and expression pattern of HtrA2 in HCC and confirmed its independent value for predicting outcomes via Cox analyses. LinkedOmics and GEPIA2 were used to construct the coexpression and functional networks of HtrA2. Additionally, the data obtained from TCGA was analyzed to investigate the relationship between the infiltration of immune cells and HtrA2 mRNA expression. Finally, the expression pattern of HtrA2 in HCC was confirmed by wet-lab experiments. The results showed high HtrA2 expression (P < 0.001) presented in tumor tissues in TCGA-HCC. Moreover, high HtrA2 expression was confirmed to be associated with poor HCC patient survival (P < 0.05). HtrA2 has also been recognized as an essential risk factor for overall survival (P=0.01, HR = 1.654, 95% CI 1.128-2.425), disease-specific survival (P=0.004, HR = 2.204, 95% CI 1.294-3.753), and progression-free interval (P=0.007, HR = 1.637, 95% CI 1.145-2.341) of HCC. HCC patients with low HtrA2 methylation had worse overall survival than patients with high methylation (P=0.0019). Functional network analysis suggests that HtrA2 regulates mitochondrial homeostasis through pathways involving multiple microRNAs and transcription factors in HCC. In addition, HtrA2 expression correlated with infiltrating levels of multiple immune cell populations. At last, increased expression of HtrA2 in HCC was confirmed using wet-lab experiments. Our study provides evidence that the upregulation of HtrA2 in HCC is an independent predictor of prognosis. Our results provide the foundation for further study on the roles of HtrA2 in HCC tumorigenesis.

Critical roles of PTPN family members regulated by non-coding RNAs in tumorigenesis and immunotherapy

Since tyrosine phosphorylation is reversible and dynamic in vivo, the phosphorylation state of proteins is controlled by the opposing roles of protein tyrosine kinases (PTKs) and protein tyrosine phosphatase (PTPs), both of which perform critical roles in signal transduction. Of these, intracellular non-receptor PTPs (PTPNs), which belong to the largest class I cysteine PTP family, are essential for the regulation of a variety of biological processes, including but not limited to hematopoiesis, inflammatory response, immune system, and glucose homeostasis. Additionally, a substantial amount of PTPNs have been identified to hold crucial roles in tumorigenesis, progression, metastasis, and drug resistance, and inhibitors of PTPNs have promising applications due to striking efficacy in antitumor therapy. Hence, the aim of this review is to summarize the role played by PTPNs, including PTPN1/PTP1B, PTPN2/TC-PTP, PTPN3/PTP-H1, PTPN4/PTPMEG, PTPN6/SHP-1, PTPN9/PTPMEG2, PTPN11/SHP-2, PTPN12/PTP-PEST, PTPN13/PTPL1, PTPN14/PEZ, PTPN18/PTP-HSCF, PTPN22/LYP, and PTPN23/HD-PTP, in human cancer and immunotherapy and to comprehensively describe the molecular pathways in which they are implicated. Given the specific roles of PTPNs, identifying potential regulators of PTPNs is significant for understanding the mechanisms of antitumor therapy. Consequently, this work also provides a review on the role of non-coding RNAs (ncRNAs) in regulating PTPNs in tumorigenesis and progression, which may help us to find effective therapeutic agents for tumor therapy.

miR-4461 inhibits the progression of Gallbladder carcinoma via regulating EGFR/AKT signaling

Increasing evidence has demonstrated that microRNAs (miRNAs) participated in the tumorigenesis, progression and recurrence of various malignancies including Gallbladder carcinoma (GBC). miR-4461 was reported to work as a tumor suppressor gene in renal cell carcinoma. However, the role of miR-4461 in GBC remains unknown. Herein, we show that miR-4461 is downregulated in gallbladder cancer stem cells (CSCs). Forced miR-4461 expression attenuates the self-renewal, tumorigenicity of gallbladder CSCs, and inhibits proliferation and metastasis of GBC cells. Conversely, miR-4461 knockdown promotes the self-renewal of gallbladder CSCs, and facilities proliferation and metastasis of GBC cells. Mechanistically, miR-4461 inhibits GBC progression via downregulating EGFR/AKT pathway. Special EGFR siRNA or AKT overexpression virus abolishes the discrepancy of self-renewal, tumorigenesis, growth, and metastasis between miR-4461 overexpression GBC cells and their control cells. In conclusion, miR-4461 suppresses GBC cells self-renewal, tumorigenicity, proliferation, and metastasis by inactivating EGFR/AKT signaling, and may therefore prove to be a potential therapeutic target for GBC patients.

Mechanisms of Pharmacoresistance in Hepatocellular Carcinoma: New Drugs but Old Problems

Hepatocellular carcinoma (HCC) is a malignancy with poor prognosis when diagnosed at advanced stages in which curative treatments are no longer applicable. A small group of these patients may still benefit from transarterial chemoembolization. The only therapeutic option for most patients with advanced HCC is systemic pharmacological treatments based on tyrosine kinase inhibitors (TKIs) and immunotherapy. Available drugs only slightly increase survival, as tumor cells possess additive and synergistic mechanisms of pharmacoresistance (MPRs) prior to or enhanced during treatment. Understanding the molecular basis of MPRs is crucial to elucidate the genetic signature underlying HCC resistome. This will permit the selection of biomarkers to predict drug treatment response and identify tumor weaknesses in a personalized and dynamic way. In this article, we have reviewed the role of MPRs in current first-line drugs and the combinations of immunotherapeutic agents with novel TKIs being tested in the treatment of advanced HCC.

Long noncoding RNA SNHG6 promotes papillary thyroid cancer cells proliferation via regulating miR-186/CDK6 axis

Background

Papillary thyroid cancer (PTC) is a common endocrine malignancy, and its incidence rate has been increasing in recent years. Long noncoding RNAs (lncRNAs) participate in cell biological processes through a variety of regulatory ways, and play an essential role in tumor development.

Methods

This study explored the expression of lncRNA small nucleolar RNA host gene 6 (SNHG6) in PTC by bioinformatics analysis, and quantitative real-time PCR (qRT-PCR). Cell counting kit-8 (CCK-8) assay, colony formation assay, and 5-ethynyl-2'-deoxyuridine (EdU) assay were used to study the effect of SNHG6 on the proliferation of PTC cells. Luciferase reporter gene assay and western blot were used to study the mechanism.

Results

SNHG6 was highly expressed in PTC tissue samples and cell lines. In vitro, overexpression of SNHG6 promoted the proliferation of PTC cells, while silencing SNHG6 inhibited the proliferation of PTC cells. miR-186 is the downstream target of SNHG6. SNHG6 regulates the proliferation of PTC cells through miR-186. In addition, CDK6 is the target gene of miR-186, which can inhibit the expression of CDK6 protein. SNHG6 can promote the expression of CDK6 by regulating miR-186.

Conclusions

SNHG6 is highly expressed in PTC and can promote the proliferation of PTC cells by regulating the miR-186/CDK6 axis, which is expected to become a potential therapeutic target for PTC.

Epigenetic Changes Affecting the Development of Hepatocellular Carcinoma

Simple Summary

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

Abstract

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