LncRNA SNAI3-AS1 promotes PEG10-mediated proliferation and metastasis via decoying of miR-27a-3p and miR-34a-5p in hepatocellular carcinoma

CRISPR-based dissection of microRNA-23a ~ 27a ~ 24-2 cluster functionality in hepatocellular carcinoma

The miR-23a ~ 27a ~ 24-2 cluster, commonly upregulated in diverse cancers, including hepatocellular carcinoma (HCC), raises questions about the specific functions of its three mature miRNAs and their integrated function. Utilizing CRISPR knockout (KO), CRISPR interference (CRISPRi), and CRISPR activation (CRISPRa) technologies, we established controlled endogenous miR-23a ~ 27 ~ a24-2 cell models to unravel their roles and signaling pathways in HCC. Both miR-23a KO and miR-27a KO displayed reduced cell growth in vitro and in vivo, revealing an integrated oncogenic function. Functional analysis indicated cell cycle arrest, particularly at the G2/M phase, through the downregulation of CDK1/cyclin B activation. High-throughput RNA-seq, combined with miRNA target prediction, unveiled the miR-23a/miR-27a-regulated gene network, validated through diverse technologies. While miR-23a and miR-27a exhibited opposing roles in cell migration and mesenchymal-epithelial transition, an integrated CRISPRi/a analysis suggested an oncogenic role of the miR-23a ~ 27a ~ 24-2 cluster in cell migration. This involvement potentially encompasses two signaling axes: miR-23a-BMPR2 and miR-27a-TMEM170B in HCC cells. In conclusion, our CRISPRi/a study provides a valuable tool for comprehending the integrated roles and underlying mechanisms of endogenous miRNA clusters, paving the way for promising directions in miRNA-targeted therapy interventions.

Regulation and targeting of SREBP-1 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is an increasing burden on global public health and is associated with enhanced lipogenesis, fatty acid uptake, and lipid metabolic reprogramming. De novo lipogenesis is under the control of the transcription factor sterol regulatory element-binding protein 1 (SREBP-1) and essentially contributes to HCC progression. Here, we summarize the current knowledge on the regulation of SREBP-1 isoforms in HCC based on cellular, animal, and clinical data. Specifically, we (i) address the overarching mechanisms for regulating SREBP-1 transcription, proteolytic processing, nuclear stability, and transactivation and (ii) critically discuss their impact on HCC, taking into account (iii) insights from pharmacological approaches. Emphasis is placed on cross-talk with the phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt)-mechanistic target of rapamycin (mTOR) axis, AMP-activated protein kinase (AMPK), protein kinase A (PKA), and other kinases that directly phosphorylate SREBP-1; transcription factors, such as liver X receptor (LXR), peroxisome proliferator-activated receptors (PPARs), proliferator-activated receptor γ co-activator 1 (PGC-1), signal transducers and activators of transcription (STATs), and Myc; epigenetic mechanisms; post-translational modifications of SREBP-1; and SREBP-1-regulatory metabolites such as oxysterols and polyunsaturated fatty acids. By carefully scrutinizing the role of SREBP-1 in HCC development, progression, metastasis, and therapy resistance, we shed light on the potential of SREBP-1-targeting strategies in HCC prevention and treatment.

LINC01535 promotes hepatocellular carcinoma proliferation and metastasis by regulating the miR-214-3p/VASP axis

Background: Emerging evidence has indicated that long noncoding RNAs (lncRNAs) are associated with the development and progression of several carcinomas, including hepatocellular carcinoma (HCC). However, the role of LINC01535 in HCC is still unknown. Materials and methods: In this study, RNA-seq, CCK-8, colony formation, wound healing, Transwell and tumor xenograft assays were used to explore the function of LINC01535 in the proliferation and metastasis of HCC in vitro and in vivo. Fluorescence in situ hybridization (FISH) assay, bioinformatics analysis, dual-luciferase assay, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis were used to reveal the interactions of LINC01535, miR-214-3p and VASP. Results: LINC01535 was overexpressed in HCC tissues and HCC cell lines. Gain- and loss-of-function studies revealed that LINC01535 could promote HCC cell proliferation, migration and invasion both in vitro and in vivo. In addition, upregulation of LINC01535 significantly decreased the expression of microRNA-214-3p (miR-214-3p), which was found closely associated with suppressing tumor progression. Moreover, VASP was identified as a direct downstream target gene of miR-214-3p. LINC01535 positively regulated VASP expression by sponging miR-214-3p, and VASP overexpression activated the PI3K/AKT signaling pathway and stimulated epithelial-to-mesenchymal transition (EMT) in HCC. Conclusions: Our study first found that LINC01535 promoted HCC progression by regulating its downstream target, the miR-214-3p/VASP axis, via the PI3K/AKT signaling pathway. The function and novel regulatory mechanism of LINC01535 may provide a valuable target for the diagnosis and treatment of HCC patients.

Abrogation of USP9X Is a Potential Strategy to Decrease PEG10 Levels and Impede Tumor Progression in Cutaneous T-Cell Lymphoma

Advanced-stage cutaneous T-cell lymphomas (CTCLs) are notorious for their highly aggressive behavior, resistance to conventional treatments, and poor prognosis, particularly when large-cell transformation occurs. PEG10 has been recently proposed as a potent driver for large-cell transformation in CTCL. However, the targeting of PEG10 continues to present a formidable clinical challenge that has yet to be addressed. In this study, we report an important post-translational regulatory mechanism of PEG10 in CTCL. USP9X, a deubiquitinase, interacted with and deubiquitinated PEG10, thereby stabilizing PEG10. Knockdown of USP9X or pharmacological targeting of USP9X resulted in a prominent downregulation of PEG10 and its downstream pathway in CTCL. Moreover, USP9X inhibition conferred tumor cell growth disadvantage and enhanced apoptosis in vitro, an effect that occurred in part through its regulation on PEG10. Furthermore, we demonstrated that inhibition of USP9X obviously restrained CTCL tumor growth in vivo and that high expression of USP9X is associated with poor survival in patients with CTCL. Collectively, our findings uncover USP9X as a key post-translational regulator in the stabilization of PEG10 and suggest that targeting PEG10 stabilization through USP9X inhibition may represent a promising therapeutic strategy for advanced-stage CTCL.

Polyubiquitylated rice stripe virus NS3 translocates to the nucleus to promote cytosolic virus replication via miRNA-induced fibrillin 2 upregulation

Viruses are encapsidated mobile genetic elements that rely on host cells for replication. Several cytoplasmic RNA viruses synthesize proteins and/or RNAs that translocate to infected cell nuclei. However, the underlying mechanisms and role(s) of cytoplasmic-nuclear trafficking are unclear. We demonstrate that infection of small brown planthoppers with rice stripe virus (RSV), a negarnaviricot RNA virus, results in K63-linked polyubiquitylation of RSV's nonstructural protein 3 (NS3) at residue K127 by the RING ubiquitin ligase (E3) LsRING. In turn, ubiquitylation leads to NS3 trafficking from the cytoplasm to the nucleus, where NS3 regulates primary miRNA pri-miR-92 processing through manipulation of the microprocessor complex, resulting in accumulation of upregulated miRNA lst-miR-92. We show that lst-miR-92 regulates the expression of fibrillin 2, an extracellular matrix protein, thereby increasing RSV loads. Our results highlight the manipulation of intranuclear, cytoplasmic, and extracellular components by an RNA virus to promote its own replication in an insect vector.

DHRS4-AS1 regulate gastric cancer apoptosis and cell proliferation by destabilizing DHX9 and inhibited the association between DHX9 and ILF3

Gastric cancer (GC) causes millions of cancer-related deaths due to anti-apoptosis and rapid proliferation. However, the molecular mechanisms underlying GC cell proliferation and anti-apoptosis remain unclear. The expression levels of DHRS4-AS1 in GC were analyzed based on GEO database and recruited GC patients in our institution. We found that DHRS4-AS1 was significantly downregulated in GC. The expression of DHRS4-AS1 in GC tissues showed a significant correlation with tumor size, advanced pathological stage, and vascular invasion. Moreover, DHRS4-AS1 levels in GC tissues were significantly associated with prognosis. DHRS4-AS1 markedly inhibited GC cell proliferation and promotes apoptosis in vitro and in vivo assays. Mechanically, We found that DHRS4-AS1 bound to pro-oncogenic DHX9 (DExH-box helicase 9) and recruit the E3 ligase MDM2 that contributed to DHX9 degradation. We also confirmed that DHRS4-AS1 inhibited DHX9-mediated cell proliferation and promotes apoptosis. Furthermore, we found DHX9 interact with ILF3 (Interleukin enhancer Binding Factor 3) and activate NF-kB Signaling in a ILF3-dependent Manner. Moreover, DHRS4-AS1 can also inhibit the association between DHX9 and ILF3 thereby interfered the activation of the signaling pathway. Our results reveal new insights into mechanisms underlying GC progression and indicate that LncRNA DHRS4-AS1 could be a future therapeutic target and a biomarker for GC diagnosis.

METTL3 facilitates multiple myeloma tumorigenesis by enhancing YY1 stability and pri-microRNA-27 maturation in m6A-dependent manner

Multiple myeloma (MM) is a pernicious plasma cell disorder and has a poor prognosis. N6-methyladenosine (m6A) is an abundant epigenetic RNA modification and is important in cancer progression. Nevertheless, the function of m6A and its regulator METTL3 in MM are rarely reported. Here, we identified the m6A "writers", METTL3, was enhanced in MM and found that Yin Yang 1 (YY1) and primary-miR-27a-3p were the potential target for METTL3. METTL3 promoted primary-miR-27a-3p maturation and YY1 mRNA stability in an m6A manner. YY1 also was found to facilitate miR-27a-3p transcription. METTL3 affected the growth, apoptosis, and stemness of MM cells through accelerating the stability of YY1 mRNA and the maturation of primary-miR-27a-3p in vitro and in vivo. Our results reveal the key function of the METTL3/YY1/miR-27a-3p axis in MM and may provide fresh insights into MM therapy.

Identification of an immune-related 6-lncRNA panel with a good performance for prognostic prediction in hepatocellular carcinoma by integrated bioinformatics analysis

Hepatocellular carcinoma (HCC) is one of the most malignant tumors with a poor prognosis. The long non-coding RNA (lncRNA) has been found to have great potential as a prognostic biomarker or therapeutic target for cancer patients. However, the prognostic value and tumor immune infiltration of lncRNAs in HCC has yet to be fully elucidated. To identify prognostic biomarkers of lncRNA in HCC by integrated bioinformatics analysis and explore their functions and relationship with tumor immune infiltration. The prognostic risk assessment model for HCC was constructed by comprehensively using univariate/multivariate Cox regression analysis, Kaplan-Meier survival analysis, and the least absolute shrinkage and selection operator regression analysis. Subsequently, the accuracy, independence, and sensitivity of our model were evaluated, and a nomogram for individual prediction in the clinic was constructed. Tumor immune microenvironment (TIME), immune checkpoints, and human leukocyte antigen alleles were compared in high- and low-risk patients. Finally, the functions of our lncRNA signature were examined using Gene Ontology, Kyoto Encyclopedia of Genes and Genomes enrichment analysis, and gene set enrichment analysis. A 6-lncRNA panel of HCC consisting of RHPN1-AS1, LINC01224, CTD-2510F5.4, RP1-228H13.5, LINC01011, and RP11-324I22.4 was eventually identified, and show good performance in predicting the survivals of patients with HCC and distinguishing the immunomodulation of TIME of high- and low-risk patients. Functional analysis also suggested that this 6-lncRNA panel may play an essential role in promoting tumor progression and immune regulation of TIME. In this study, 6 potential lncRNAs were identified as the prognostic biomarkers in HCC, and the regulatory mechanisms involved in HCC were initially explored.

Epigenetically silenced lncRNA SNAI3-AS1 promotes ferroptosis in glioma via perturbing the m6A-dependent recognition of Nrf2 mRNA mediated by SND1

BACKGROUND

Ferroptosis has been linked to tumor progression and resistance to antineoplastic therapy. Long noncoding RNA (lncRNA) exerts a regulatory role in various biological processes of tumor cells, while the function and molecular mechanism of lncRNA in ferroptosis are yet to be clarified in glioma.

METHODS

Both gain-of-function and loss-of-function experiments were employed to investigate the effects of SNAI3-AS1 on the tumorigenesis and ferroptosis susceptibility of glioma in vitro and in vivo. Bioinformatics analysis, Bisulfite sequencing PCR, RNA pull-down, RIP, MeRIP and dual-luciferase reporter assay were performed to explore the low expression mechanism of SNAI3-AS1 and the downstream mechanism of SNAI3-AS1 in ferroptosis susceptibility of glioma.

RESULTS

We found that ferroptosis inducer erastin downregulates SNAI3-AS1 expression in glioma by increasing the DNA methylation level of SNAI3-AS1 promoter. SNAI3-AS1 functions as a tumor suppressor in glioma. Importantly, SNAI3-AS1 enhances the anti-tumor activity of erastin by promoting ferroptosis both in vitro and in vivo. Mechanistically, SNAI3-AS1 competitively binds to SND1 and perturbs the m⁶A-dependent recognition of Nrf2 mRNA 3'UTR by SND1, thereby reducing the mRNA stability of Nrf2. Rescue experiments confirmed that SND1 overexpression and silence can rescue the gain- and loss-of-function ferroptotic phenotypes of SNAI3-AS1, respectively.

CONCLUSIONS

Our findings elucidate the effect and detailed mechanism of SNAI3-AS1/SND1/Nrf2 signalling axis in ferroptosis, and provide a theoretical support for inducing ferroptosis to improve glioma treatment.

Making Sense of Antisense lncRNAs in Hepatocellular Carcinoma

Transcriptome complexity is emerging as an unprecedented and fascinating domain, especially by high-throughput sequencing technologies that have unveiled a plethora of new non-coding RNA biotypes. This review covers antisense long non-coding RNAs, i.e., lncRNAs transcribed from the opposite strand of other known genes, and their role in hepatocellular carcinoma (HCC). Several sense-antisense transcript pairs have been recently annotated, especially from mammalian genomes, and an understanding of their evolutionary sense and functional role for human health and diseases is only beginning. Antisense lncRNAs dysregulation is significantly involved in hepatocarcinogenesis, where they can act as oncogenes or oncosuppressors, thus playing a key role in tumor onset, progression, and chemoradiotherapy response, as deduced from many studies discussed here. Mechanistically, antisense lncRNAs regulate gene expression by exploiting various molecular mechanisms shared with other ncRNA molecules, and exploit special mechanisms on their corresponding sense gene due to sequence complementarity, thus exerting epigenetic, transcriptional, post-transcriptional, and translational controls. The next challenges will be piecing together the complex RNA regulatory networks driven by antisense lncRNAs and, ultimately, assigning them a function in physiological and pathological contexts, in addition to defining prospective novel therapeutic targets and innovative diagnostic tools.

Comprehensive analysis of oxidative stress-related lncRNA signatures in glioma reveals the discrepancy of prognostic and immune infiltration

Oxidative stress refers to the process of reactive oxide species (ROS) increase in human body due to various factors, which leads to oxidative damage in human tissues. Current studies have confirmed that sustained oxidative stress is one of the distinctive features throughout the development of tumors. Numerous reports have shown that lncRNAs can regulate the process of oxidative stress through multiple pathways. However, the relationship between glioma-associated oxidative stress and lncRNAs is not clearly investigated. RNA sequencing data of GBM (glioblastoma) and LGG (low grade glioma) and corresponding clinical data were retrieved from the TCGA database. Oxidative stress related lncRNAs (ORLs) were identified by Pearson correlation analysis. Prognostic models for 6-ORLs were structured in the training cohort by univariate Cox regression analysis, multivariate Cox regression analysis and LASSO regression analysis. We constructed the nomogram and verified its predictive efficacy by Calibration curves and DCA decision curves. The biological functions and pathways of 6-ORLs-related mRNAs were inferred by Gene Set Enrichment Analysis. Immune cell abundance and immune function associated with risk score (RS) were estimated by ssGSEA, CIBERSORT and MCPcounter synthetically. External validation of the signature was completed using the CGGA-325 and CGGA-693 datasets. 6-ORLs signature-AC083864.2, AC107294.1, AL035446.1, CRNDE, LINC02600, and SNAI3-AS1-were identified through our analysis as being predictive of glioma prognosis. Kaplan-Meier and ROC curves indicated that the signature has a dependable predictive efficacy in the TCGA training cohort, validation cohort and CGGA-325/CGGA-693 test cohort. The 6-ORLs signature were verified to be independent prognostic predictors by multivariate cox regression and stratified survival analysis. Nomogram built with risk scores had strong predictive efficacy for patients' overall survival (OS). The outcomes of the functional enrichment analysis revealing potential molecular regulatory mechanisms for the 6-ORLs. Patients in the high-risk subgroup presented a significant immune microenvironment of macrophage M0 and cancer-associated fibroblast infiltration which was associated with a poorer prognosis. Finally, the expression levels of 6-ORLs in U87/U251/T98/U138 and HA1800 cell lines were verified by RT-qPCR. The nomogram in this study has been made available as a web version for clinicians. This 6-ORLs risk signature has the capabilities to predict the prognosis of glioma patients, assist in evaluating immune infiltration, and assess the efficacy of various anti-tumor systemic therapy regimens.

The MYC-regulated lncRNA LNROP (ENSG00000254887) enables MYC-driven cell proliferation by controlling the expression of OCT2

MYC controls most of the non-coding genome. Several long noncoding transcripts were originally identified in the human B cell line P496-3 and then shown to be required for MYC-driven proliferation of Burkitt lymphoma-derived RAMOS cells. In this study, we used RAMOS cells exclusively as a representative of the human B cell lineage. One of the MYC-controlled lncRNAs required for RAMOS cell proliferation is ENSG00000254887 which we will term LNROP (long non-coding regulator of POU2F2). In the genome, LNROP is located in close proximity of POU2F2, the gene encoding OCT2. OCT2 is a transcription factor with important roles in sustaining the proliferation of human B cells. Here we show that LNROP is a nuclear RNA and a direct target of MYC. Downregulation of LNROP attenuates the expression of OCT2. This effect of LNROP on the expression of OCT2 is unidirectional as downregulation of OCT2 does not alter the expression of LNROP. Our data suggest that LNROP is a cis-acting regulator of OCT2. To illustrate the downstream reach of LNROP, we chose a prominent target of OCT2, the tyrosine phosphatase SHP-1. Downregulation of OCT2 elevates the expression of SHP-1. Our data suggest the following path of interactions: LNROP enables the proliferation of B cells by positively and unidirectionally regulating the growth-stimulatory transcription factor OCT2. In actively proliferating B cells, OCT2 attenuates the expression and anti-proliferative activity of SHP-1.

Identification of a cellular senescence-related-lncRNA (SRlncRNA) signature to predict the overall survival of glioma patients and the tumor immune microenvironment

Background: Gliomas are brain tumors that arise from glial cells, and they are the most common primary intracranial tumors with a poor prognosis. Cellular senescence plays a critical role in cancer, especially in glioma. In this study, we constructed a senescence-related lncRNA (SRlncRNA) signature to assess the prognosis of glioma. Methods: The Cancer Genome Atlas was used to collect SRlncRNA transcriptome profiles and clinical data about glioma. Patients were randomized to training, testing, and whole cohorts. LASSO and Cox regression analyses were employed to construct the SRlncRNA signature, and Kaplan-Meier (K-M) analysis was performed to determine each cohort's survival. Receiver operating characteristic (ROC) curves were applied to verify the accuracy of this signature. Gene set enrichment analysis was used to visualize functional enrichment (GSEA). The CIBERSORT algorithm, ESTIMATE and TIMER databases were utilized to evaluate the differences in the infiltration of 22 types of immune cells and their association with the signature. RT-qPCR and IHC were used to identify the consistency of the signature in tumor tissue. Results: An SRlncRNA signature consisting of six long non-coding RNAs (lncRNAs) was constructed, and patients were divided into high-risk and low-risk groups by the median of their riskscore. The KM analysis showed that the high-risk group had worse overall survival, and the ROC curve confirmed that the riskscore had more accurate predictive power. A multivariate Cox analysis and its scatter plot with clinical characteristics confirmed the riskscore as an independent risk factor for overall survival. GSEA showed that the GO and KEGG pathways were mainly enriched in the immune response to tumor cells, p53 signaling pathway, mTOR signaling pathway, and Wnt signaling pathway. Further validation also yielded significant differences in the risk signature in terms of immune cell infiltration, which may be closely related to prognostic differences, and qRT-PCR and IHC confirmed the consistency of the expression differences in the major lncRNAs with those in the prediction model. Conclusion Our findings indicated that the SRlncRNA signature might be used as a predictive biomarker and that there is a link between it and immune infiltration. This discovery is consistent with the present categorization system and may open new avenues for research and personalized therapy.

M7G-related LncRNAs: A comprehensive analysis of the prognosis and immunity in glioma

Today, numerous international researchers have demonstrated that N7-methylguanosine (m7G) related long non-coding RNAs (m7G-related lncRNAs) are closely linked to the happenings and developments of various human beings’ cancers. However, the connection between m7G-related lncRNAs and glioma prognosis has not been investigated. We did this study to look for new potential biomarkers and construct an m7G-related lncRNA prognostic signature for glioma. We identified those lncRNAs associated with DEGs from glioma tissue sequences as m7G-related lncRNAs. First, we used Pearson’s correlation analysis to identify 28 DEGs by glioma and normal brain tissue gene sequences and predicated 657 m7G-related lncRNAs. Then, eight lncRNAs associated with prognosis were obtained and used to construct the m7G risk score model by lasso and Cox regression analysis methods. Furthermore, we used Kaplan-Meier analysis, time-dependent ROC, principal component analysis, clinical variables, independent prognostic analysis, nomograms, calibration curves, and expression levels of lncRNAs to determine the model’s accuracy. Importantly, we validated the model with external and internal validation methods and found it has strong predictive power. Finally, we performed functional enrichment analysis (GSEA, aaGSEA enrichment analyses) and analyzed immune checkpoints, associated pathways, and drug sensitivity based on predictors. In conclusion, we successfully constructed the formula of m7G-related lncRNAs with powerful predictive functions. Our study provides instructional value for analyzing glioma pathogenesis and offers potential research targets for glioma treatment and scientific research.

LncRNA NALT1 promotes colorectal cancer progression via targeting PEG10 by sponging microRNA-574-5p

Colorectal cancer (CRC) is currently one of the commonest tumors and the main reason for cancer-related deaths worldwide. It has been reported that long non-coding RNAs (lncRNAs) act as important indicators and regulators in various cancers. There is an urgent need to explore new lncRNA biomarkers in CRC, as well as their functions and molecular mechanisms. NALT1 has been implicated in the occurrence of gastric cancer (GC). However, the detailed function and mechanism of NALT1 in CRC progress have not been reported. In this study, RT-qPCR was conducted to detect the expression of NALT1 in 76 CRC patients ranging from stages I through IV. To assess the biological function of NALT1, loss- and gain-of-function experiments were conducted both in vivo and in vitro. Moreover, RNA-seq, bioinformatics analysis, RNA pulldown assay, dual-luciferase reporter, Ago2-RIP, quantitative PCR, Western blot assays, and rescue experiments were performed to reveal the molecular mechanisms of competitive endogenous RNAs (ceRNAs). It was observed that high expression of NALT1 was markedly correlated with advanced cancer stage in the clinic. Functionally, NALT1 downregulation inhibited cell proliferation, migration and invasion, whereas NALT1 overexpression exhibited an opposite trend both in vivo and in vitro. Bioinformatics analysis, RNA pulldown, Ago2-RIP, and luciferase reporter assays showed that miRNA-574-5p was a target of NALT1. Additionally, dual-luciferase reporter assays, Ago2-RIP, and rescue experiments indicated that miRNA-574-5p could target the PEG10 gene directly. Our results suggested that NALT1 promoted CRC proliferation and migration by sponging miRNA-574-5p to upregulate PEG10 expression, and implied that NALT1 might act as a promising biomarker and therapeutic target for CRC.

Emerging Role of Non-Coding RNAs in Aortic Dissection

Aortic dissection (AD) is a fatal cardiovascular acute disease with high incidence and mortality, and it seriously threatens patients’ lives and health. The pathogenesis of AD mainly includes vascular inflammation, extracellular matrix degradation, and phenotypic conversion as well as apoptosis of vascular smooth muscle cells (VSMCs); however, its detailed mechanisms are still not fully elucidated. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are an emerging class of RNA molecules without protein-coding ability, and they play crucial roles in the progression of many diseases, including AD. A growing number of studies have shown that the dysregulation of ncRNAs contributes to the occurrence and development of AD by modulating the expression of specific target genes or the activity of related proteins. In addition, some ncRNAs exhibit great potential as promising biomarkers and therapeutic targets in AD treatment. In this review, we systematically summarize the recent findings on the underlying mechanism of ncRNA involved in AD regulation and highlight their clinical application as biomarkers and therapeutic targets in AD treatment. The information reviewed here will be of great benefit to the development of ncRNA-based therapeutic strategies for AD patients.

Function of the Long Noncoding RNAs in Hepatocellular Carcinoma: Classification, Molecular Mechanisms, and Significant Therapeutic Potentials

Hepatocellular carcinoma (HCC) is the most common and serious type of primary liver cancer. HCC patients have a high death rate and poor prognosis due to the lack of clear signs and inadequate treatment interventions. However, the molecular pathways that underpin HCC pathogenesis remain unclear. Long non-coding RNAs (lncRNAs), a new type of RNAs, have been found to play important roles in HCC. LncRNAs have the ability to influence gene expression and protein activity. Dysregulation of lncRNAs has been linked to a growing number of liver disorders, including HCC. As a result, improved understanding of lncRNAs could lead to new insights into HCC etiology, as well as new approaches for the early detection and treatment of HCC. The latest results with respect to the role of lncRNAs in controlling multiple pathways of HCC were summarized in this study. The processes by which lncRNAs influence HCC advancement by interacting with chromatin, RNAs, and proteins at the epigenetic, transcriptional, and post-transcriptional levels were examined. This critical review also highlights recent breakthroughs in lncRNA signaling pathways in HCC progression, shedding light on the potential applications of lncRNAs for HCC diagnosis and therapy.

Integrated analysis to reveal potential therapeutic targets and prognostic biomarkers of skin cutaneous melanoma

Skin cutaneous melanoma (SKCM) is a malignant tumor with high mortality rate in human, and its occurrence and development are jointly regulated by genes and the environment. However, the specific pathogenesis of SKCM is not completely understood. In recent years, an increasing number of studies have reported the important role of competing endogenous RNA (ceRNA) regulatory networks in various tumors; however, the complexity and specific biological effects of the ceRNA regulatory network of SKCM remain unclear. In the present study, we obtained a ceRNA regulatory network of long non-coding RNAs, microRNAs, and mRNAs related to the phosphatase and tensin homolog (PTEN) in SKCM and identified the potential diagnostic and prognostic markers related to SKCM. We extracted the above three types of RNA involved in SKCM from The Cancer Genome Atlas database. Through bioinformatics analysis, the OIP5-AS1-hsa-miR-186-5p/hsa-miR-616-3p/hsa-miR-135a-5p/hsa-miR-23b-3p/hsa-miR-374b-5p-PTPRC/IL7R/CD69 and MALAT1-hsa-miR-135a-5p/hsa-miR-23b-3p/hsa-miR-374b-5p-IL7R/CD69 ceRNA networks were found to be related to the prognosis of SKCM. Finally, we determined the OIP5-AS1-PTPRC/IL7R/CD69 and MALAT1-IL7R/CD69 axes in ceRNA as a clinical prognostic model using correlation and Cox regression analyses. Additionally, we explored the possible role of these two axes in affecting gene expression and immune microenvironment changes and the occurrence and development of SKCM through methylation and immune infiltration analyses. In summary, the ceRNA-based OIP5-AS1-PTPRC/IL7R/CD69 and MALAT1-IL7R/CD69 axes may be a novel and important approach for the diagnosis and prognosis of SKCM.

Machine Learning-Based Integration Develops a Pyroptosis-Related lncRNA Model to Enhance the Predicted Value of Low-Grade Glioma Patients

Background

Molecular features have been included in the categorization of gliomas because they may be excellent predictors of tumor prognosis. Lower-grade glioma (LGGs, which comprise grade 2 and grade 3 gliomas) patients have a wide variety of outcomes. The goal of this research is to investigate a pyroptosis-based long noncoding RNA (lncRNA) profile and see whether it can be used to predict LGG prognosis.

Methods

The Genotype-Tissue Expression (GTEx) and Cancer Genome Atlas (TCGA) datasets were utilized to get RNA data and clinical information for this research. Six considerably related lncRNAs (AL355574.1, AL355974.2, Z97989.1, SNAI3-AS1, LINC02593, and CYTOR) were selected using Cox regression (univariate and multivariate) and LASSO Cox regression. A variety of statistical techniques, including ROC curves, nomogram, and Kaplan-Meier curves, were utilized to verify the risk score's accuracy. Following that, bioinformatics studies were carried out to investigate the possible molecular processes that influence LGG prognosis. The variations in pathway enrichment were investigated using GSEA. The immune microenvironment inconsistencies were investigated using CIBERSORT, ESTIMATE, MCPcounter, TIMER algorithms, and ssGSEA.

Results

We discovered six lncRNAs with distinct expression patterns that are linked to LGG prognosis. Kaplan-Meier studies showed a signature of high-risk lncRNAs associated with a poor prognosis for LGG. Furthermore, the AUC of the lncRNA signature was 0.763, indicating that they may be used to predict LGG prognosis. In predicting LGG prognosis, our risk assessment approach outperformed conventional clinicopathological characteristics. In the high-risk group of people, GSEA identified tumor-related pathways and immune-related pathways. Furthermore, T cell-related activities such as T cell coinhibition and costimulation, check point, APC coinhibition and costimulation, CCR, and inflammatory promoting were shown to be substantially different between the two groups in TCGA analysis. Immune checkpoints including PD-1, CTLA4, and PD-L1 were expressed differentially in the two groups as well.

Conclusion

This study found that pyroptosis-based lncRNAs were useful in predicting LGG patients' survival, suggesting that they may be used as a therapeutic target in the future.

Prognostic signature based on m6A-related lncRNAs to predict overall survival in pancreatic ductal adenocarcinoma

A growing body of evidence indicates that N6-methyladenosine (m6A) and long non-coding RNAs (lncRNAs) play crucial roles in the progression of PDAC and the treatment response of patients with pancreatic ductal adenocarcinoma (PDAC). In this study, we identified m6A-related lncRNAs to reveal their association with PDAC in prognosis and tumor immune environment. A prognostic signature based on 9 m6A-related lncRNAs was established, and the high-risk patients exhibited a significantly worse prognosis than low-risk patients. The predictive capacity was confirmed by receiver operating characteristic (ROC) curve analysis and an independent validation cohort. Correlation analyses revealed that m6A-related lncRNA signature was significantly associated with the number of somatic mutations, immunocyte infiltration, immune function, immune checkpoints, tumor microenvironment (TME) score, and sensitivity to chemotherapeutic drugs. Consequently, we constructed a highly accurate nomogram for improving clinical applicability of signature and exhibited superior predictive accuracy than both the signature and tumor stage. In conclusion, our proposed m6A-related lncRNA signature is a potential indicator predictive of prognosis and immunotherapeutic responses in PDAC patients.

Designing strategies of small-molecule compounds for modulating non-coding RNAs in cancer therapy

Non-coding RNAs (ncRNAs) have been defined as a class of RNA molecules transcribed from the genome but not encoding proteins, such as microRNAs, long non-coding RNAs, Circular RNAs, and Piwi-interacting RNAs. Accumulating evidence has recently been revealing that ncRNAs become potential druggable targets for regulation of several small-molecule compounds, based on their complex spatial structures and biological functions in cancer therapy. Thus, in this review, we focus on summarizing some new emerging designing strategies, such as high-throughput screening approach, small-molecule microarray approach, structure-based designing approach, phenotypic screening approach, fragment-based designing approach, and pharmacological validation approach. Based on the above-mentioned approaches, a series of representative small-molecule compounds, including Bisphenol-A, Mitoxantrone and Enoxacin have been demonstrated to modulate or selectively target ncRNAs in different types of human cancers. Collectively, these inspiring findings would provide a clue on developing more novel avenues for pharmacological modulations of ncRNAs with small-molecule drugs for future cancer therapeutics.

HOXA-AS3 Promotes Proliferation and Migration of Hepatocellular Carcinoma Cells via the miR-455-5p/PD-L1 Axis

Hepatocellular carcinoma (HCC) is the most prevalent type of hepatic carcinoma. Long noncoding RNAs (lncRNAs) are considered crucial regulators of gene expression; however, their functions in HCC are not well understood. Thus, the present study is aimed at elucidating the functions of the lncRNA HOXA-AS3 in HCC. The functions of the HOXA-AS3/miR-455-5p/programmed death-ligand 1 (PD-L1) axis were investigated in vitro via qRT-PCR and dual-luciferase reporter assays. The effect of HOXA-AS3 expression on tumor growth and metastasis was assessed using a mouse xenograft model. High HOXA-AS3 expression was observed in the HCC cell lines. Furthermore, overexpression of HOXA-AS3 in HCC cells enhanced proliferation, migration, and invasion, regulated the cell cycle, and retarded apoptosis. We also identified an miR-455-5p binding site in HOXA-AS3. By sponging miR-455-5p, HOXA-AS3 increased the expression of PD-L1. Additionally, both the inhibition of PD-L1 and overexpression of miR-455-5p reversed the effects on cell proliferation and invasion triggered by the overexpression of HOXA-AS3. In conclusion, HOXA-AS3 modulated the functions of HCC cells through the miR-455-5p/PD-L1 axis. Therefore, HOXA-AS3 may be a novel therapeutic target for HCC.

Single-cell RNA-seq highlights a specific carcinoembryonic cluster in ovarian cancer

Expounding the heterogeneity for ovarian cancer (OC) with the cognition in developmental biology might be helpful to search for robust prognostic markers and effective treatments. In the present study, we employed single-cell RNA-seq with ovarian cancers, normal ovary, and embryo tissue to explore their heterogeneity. Then the differentiation process of clusters was explored; the pivotal cluster and markers were identified. Furthermore, the consensus clustering algorithm was used to explore the different clinical phenotypes in OC. At last, a prognostic model was construct and used to assess the prognosis for OCs. As a result, eight diverse clusters were identified, and the similarity existed in some clusters between embryo and tumours based on their gene expression. Meaningfully, a subtype of malignant epithelial cluster, PEG10⁺ EME, was associated with poor survival and was an intermediate stage of embryo to tumour. PEG10 was a CSC marker and might influence CSC self-renewal and promote cisplatin resistance via NOTCH pathway. Utilising specific gene profiles of PEG10⁺ EME based on public data sets, four phenotypes with different survival and clinical response to anti-PD-1/PD-L1 immunotherapy were identified. These insights allowed for the investigation of single-cell transcriptome of OCs and embryo, which advanced our current understanding of OC pathogenesis and resulted in promising therapeutic strategies.

A novel small-molecule antagonist enhances the sensitivity of osteosarcoma to cabozantinib in vitro and in vivo by targeting DNMT-1 correlated with disease severity in human patients

Advanced osteosarcoma (OSA) is highly aggressive and can lead to distant metastasis or recurrence. Here, a novel small-molecule inhibitor/antagonist of DNA methyltransferase 1 (DNMT-1) named DI-1 (inhibitor of DNMT-1) was explored to enhance the antitumor effect of a molecular-targeted agent, cabozantinib, on OSA cell lines. In patients with OSA, expression of DNMT-1 was negatively related with that of microRNA (miR)-34a and associated with a poor prognosis. In OSA cell lines (OSA cell line U2OS and an OSA cell line U2OSR resistance to cabozantinib), DI-1 treatment enhanced miR-34a expression by inhibiting hypermethylation of the promoter region of miR-34a mediated by DNMT-1. DI-1 enhanced the sensitivity of OSA cells (U2OS, 143B and MG63) to cabozantinib and other molecular-targeted agents by enhancing miR-34a expression and repressing activation of the Notch pathway. Mechanistically, DI-1 repressed recruitment of DNMT-1 to the promoter region of miR-34a and, in turn, decreased the methylation rate in the promoter region of miR-34a in OSA cells. These results suggest that repressing DNMT-1 activation by DI-1 enhances miR-34a expression in OSA cells and could be a promising therapeutic strategy for OSA.

SMAD4-induced knockdown of the antisense long noncoding RNA BRE-AS contributes to granulosa cell apoptosis

Antisense long noncoding RNAs (AS-lncRNAs), a sub-class of lncRNAs, are transcribed in the opposite direction from their overlapping protein-coding genes and are implicated in various physiological and pathological processes. However, their role in female reproduction remains largely unknown. Here, we report that BRE-AS, an AS-lncRNA transcript from intron 10 of the protein-coding gene BRE, is involved in granulosa cell (GC) apoptosis. Based on our previous RNA sequencing data, we identified 28 AS-lncRNAs as important in the initiation of porcine follicular atresia, with BRE-AS showing the most significant upregulation in early atretic follicles. In this study, gain- and loss-of-function assays demonstrated that BRE-AS induces early apoptosis in GCs. Mechanistically, BRE-AS acts in cis to suppress the expression of BRE, an anti-apoptotic factor, via direct interaction with the pre-mRNA transcript of the latter, inducing increased GC apoptosis. Notably, we also found that BRE-AS was upregulated in SMAD4-silenced GCs. SMAD4 was identified as a transcriptional repressor of BRE-AS because it inhibits BRE-AS expression and BRE-AS-mediated GC apoptosis. In conclusion, we not only identified a novel AS-lncRNA related to the early apoptosis of GCs and initiation of follicular atresia but also described a novel regulatory pathway, SMAD4/BRE-AS/BRE, coordinating GC function and female fertility.

A Novel Inflammatory lncRNAs Prognostic Signature for Predicting the Prognosis of Low-Grade Glioma Patients

Background

As immunotherapy has received attention as new treatments for brain cancer, the role of inflammation in the process of glioma is of particular importance. Increasing studies have further shown that long non-coding RNAs (lncRNAs) are important factors that promote the development of glioma. However, the relationship between inflammation-related lncRNAs and the prognosis of glioma patients remains unclear. The purpose of this study is to construct and validate an inflammation-related lncRNA prognostic signature to predict the prognosis of low-grade glioma patients.

Methods

By downloading and analyzing the gene expression data and clinical information of the Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) patients with low-grade gliomas, we could screen for inflammatory gene-related lncRNAs. Furthermore, through Cox and the Least Absolute Shrinkage and Selection Operator regression analyses, we established a risk model and divided patients into high- and low-risk groups based on the median value of the risk score to analyze the prognosis. In addition, we analyzed the tumor mutation burden (TMB) between the two groups based on somatic mutation data, and explored the difference in copy number variations (CNVs) based on the GISTIC algorithm. Finally, we used the MCPCounter algorithm to study the relationship between the risk model and immune cell infiltration, and used gene set enrichment analysis (GSEA), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to explore the enrichment pathways and biological processes of differentially expressed genes between the high- and low-risk groups.

Results

A novel prognostic signature was constructed including 11 inflammatory lncRNAs. This risk model could be an independent prognostic predictor. The patients in the high-risk group had a poor prognosis. There were significant differences in TMB and CNVs for patients in the high- and low-risk groups. In the high-risk group, the immune system was activated more significantly, and the expression of immune checkpoint-related genes was also higher. The GSEA, GO, and KEGG analyses showed that highly expressed genes in the high-risk group were enriched in immune-related processes, while lowly expressed genes were enriched in neuromodulation processes.

Conclusion

The risk model of 11 inflammation-related lncRNAs can serve as a promising prognostic biomarker for low-grade gliomas patients.

miR-27-3p Enhances the Sensitivity of Triple-Negative Breast Cancer Cells to the Antitumor Agent Olaparib by Targeting PSEN-1, the Catalytic Subunit of Γ-Secretase

Olaparib has been used in the treatment of triple-negative breast cancer (TNBC) with BRCA mutations. In the present study, we demonstrated the effect of miR-27-3p on the γ-secretase pathway by regulating the sensitivity of TNBC cells to olaparib. miR-27-3p, a microRNA with the potential to target PSEN-1, the catalytic subunit of γ-secretase mediating the second step of the cleavage of the Notch protein, was identified by the online tool miRDB and found to inhibit the expression of PSEN-1 by directly targeting the 3'-untranslated region (3'-UTR) of PSEN-1. The overexpression of miR-27-3p inhibited the activation of the Notch pathway via the inhibition of the cleavage of the Notch protein, mediated by γ-secretase, and, in turn, enhanced the sensitivity of TNBC cells to the antitumor agent olaparib. Transfection with PSEN-1 containing mutated targeting sites for miR-27-3p or the expression vector of the Notch protein intracellular domain (NICD) almost completely blocked the effect of miR-27-3p on the Notch pathway or the sensitivity of TNBC cells to olaparib, respectively. Therefore, our results suggest that the miR-27-3p/γ-secretase axis participates in the regulation of TNBC and that the overexpression of miR-27-3p represents a potential approach to enhancing the sensitivity of TNBC to olaparib.

Clinical value and potential mechanisms of LINC00221 in hepatocellular carcinoma based on integrated analysis

Aims:This study aimed to unveil the functional roles of LINC00221 in hepatocellular carcinoma (HCC). Materials and methods:A discovery cohort and a validation cohort were respectively used to identify and verify the clinical value of LINC00221 in HCC. Bioinformatics analysis was performed to explore its potential mechanisms. Results:LINC00221 was upregulated in HCC tissues and serum samples. Survival analysis and receiver operating characteristic curve further revealed its prognostic and diagnostic roles. Exploration of the mechanism showed that LINC00221 might exert a pro-cancer role via the lncRNA-miRNA-mRNA network.Conclusions: Our study reveals that upregulated LINC00221 can serve as a potential diagnostic and prognostic biomarker and provides novel clues as to the role of LINC00221 in HCC.

Hepigenetics: A Review of Epigenetic Modulators and Potential Therapies in Hepatocellular Carcinoma

Hepatocellular carcinoma is the fifth most common cancer worldwide and the second most lethal, following lung cancer. Currently applied therapeutic practices rely on surgical resection, chemotherapy and radiotherapy, or a combination thereof. These treatment options are associated with extreme adversities, and risk/benefit ratios do not always work in patients' favor. Anomalies of the epigenome lie at the epicenter of aberrant molecular mechanisms by which the disease develops and progresses. Modulation of these anomalous events poses a promising prospect for alternative treatment options, with an abundance of felicitous results reported in recent years. Herein, the most recent epigenetic modulators in hepatocellular carcinoma are recapitulated on.

Adsorption of miR-218 by lncRNA HOTAIR regulates PDE7A and affects glioma cell proliferation, invasion, and apoptosis

OBJECTIVE

To evaluate the role of targeted adsorption of miR-218 by long-chain non-coding RNAHOTAIR to regulate PDE7A on glioma cell proliferation, invasion, and apoptosis.

METHODS

The expressions of lncRNA HOTAIR, miR-218, and PDE7A in glioma tissues and normal parcancer tissues, NHA and glioma cell lines were determined, and correlations among the three genes were analyzed. The subcellular localization of lncRNA HOTAIR was determined by fluorescent in situ hybridization. Dual-luciferase reporter assay was used to validate the targeted relationship between lncRNA HOTAIR/miR-218/PDE7A. Glioma cells were grouped to receive intervention of lncRNA HOTAIR or miR-218. MTT, transwell, and flow cytometry were performed to determine the proliferation, invasion, and apoptosis of cells.

RESULTS

Compared with the normal tissues and cells, the expression of lncRNA HOTAIR was increased while miR-218 was suppressed in glioma tissues samples and cells (all P<0.05). Inhibition of lncRNA HOTAIR expression, was able to induce apoptosis and suppress the proliferation and invasion of cells (all P<0.05). LncRNA HOTAIR is mainly localized in the cytoplasm, and is able to adsorb miR-218 as ceRNA. The effect of knockdown of HOTAIR on glioma cells could be partially rescued by miR-218 inhibitor. The expression of PDE7A was enhanced in glioma tissues and cells compared to normal tissues and cells (all P<0.05), which positively correlated with the expression of HOTAIR (r=0.546, P<0.05) and negatively correlated with the expression of miR-218 (r=0.363, P<0.05). The targeted relationship between miR-218 and PDE7A was validated: Overexpression of miR-218 was able to suppress the proliferation and invasion of glioma cells and restrain apoptosis compared to the miR-NC group (all P<0.05). The effect of miR-218 on glioma cells could be partially rescued by PDE7A.

CONCLUSION

lncRNA HOTAIR can adsorb miR-218 to regulate expression of PDE7A and promote the malignant biologic behavior of glioma cells.

LncRNA OIP5-AS1 upregulates snail expression by sponging miR-34a to promote ovarian carcinoma cell invasion and migration

Background

Although OIP5-AS1 has been characterized as an oncogenic lncRNA in many types of cancer, its role and underlying mechanism in ovarian carcinoma (OC) remains unknown. This study aimed to investigate the role of OIP5-AS1 in OC.

Methods

OC tissues and non-tumor tissues (ovary tissues within 3 cm around tumors) were collected from 58 OC patients (age range 36 to 67 years old, mean age 51.4 ± 5.9 years old). The expression of OIP5-AS1 and snail in paired tissues were determined by RT-qPCR. The interaction between OIP5-AS1 and miR-34a was predicted by IntaRNA2.0 and confirmed by dual luciferase reporter assay. The effects of overexpression of OIP5-AS1 and miR-34a on the expression of snail were analyzed by RT-qPCR and Western blotting. Cell invasion and migration were analyzed by Transwell assay.

Results

We observed that the expression of OIP5-AS1 and snail was upregulated and positively correlated with each other in OC. RNA–RNA interaction analysis showed that OIP5-AS1 might sponge miR-34a. In OC cells, overexpression of OIP5-AS1 resulted in the upregulated expression of snail, while overexpression of miR-34a downregulated the expression of snail. In addition, overexpression of miR-34a reduced the effects of overexpression of OIP5-AS1 on the expression of snail. In cell invasion and migration assay, overexpression of OIP5-AS1 and snail resulted in increased OC cell invasion and migration, while overexpression of miR-34a decreased OC cell invasion and migration. Moreover, overexpression of miR-34a attenuated the effects of OIP5-AS1 overexpression on OC cell invasion and migration.

Conclusions

Therefore, OIP5-AS1 may upregulate snail expression in OC by sponging miR-34a to promote OC cell invasion and migration.

Long non‑coding RNA MKLN1‑AS aggravates hepatocellular carcinoma progression by functioning as a molecular sponge for miR‑654‑3p, thereby promoting hepatoma‑derived growth factor expression

Long non‑coding RNAs (lncRNAs) have recently gained attention due to their important roles in human cancer types, such as breast and gastric cancer. The present study measured alterations in muskelin 1 antisense RNA (MKLN1‑AS) expression in hepatocellular carcinoma (HCC) and evaluated its clinical value in patients with HCC. Additionally, the current study investigated the effects of MKLN1‑AS on the malignant features of HCC cells. The detailed molecular mechanisms underlying the cancer‑promoting activities of MKLN1‑AS in HCC cells were also elucidated. MKLN1‑AS expression in HCC tissues and cell lines was detected using reverse‑transcription quantitative PCR (RT‑qPCR). Cell Counting Kit‑8 assays and flow cytometry were used to determine the roles of MKLN1‑AS in HCC cell proliferation and apoptosis. Migration and invasion assays, as well as tumor xenograft experiments were conducted to analyze migration and invasion in vitro and tumor growth in vivo, respectively. The interaction among microRNA‑654‑3p (miR‑654‑3p), MKLN1‑AS and hepatoma‑derived growth factor (HDGF) in HCC was investigated using luciferase reporter assay, RNA immunoprecipitation assay, RT‑qPCR, western blotting and rescue experiments. MKLN1‑AS was upregulated in HCC tissues and cell lines, and a high MKLN1‑AS expression was associated with shorter overall survival and disease‑free survival in patients with HCC. Functionally, the knockdown of MKLN1‑AS impaired HCC cell proliferation, migration and invasion, as well as induced cell apoptosis in vitro. Knockdown of MKLN1‑AS expression also inhibited cell proliferation in vivo. The results indicated that MKLN1‑AS functioned as a competing endogenous RNA by sponging miR‑654‑3p in HCC cells. Additionally, miR‑654‑3p targeting of HDGF was positively modulated by MKLN1‑AS, and miR‑654‑3p knockdown partially abrogated this effect. Rescue experiments demonstrated that knockdown of miR‑654‑3p and overexpression of HDGF both abolished MKLN1‑AS knockdown‑induced cellular processes in HCC. In summary, MKLN1‑AS induced pro‑oncogenic effects during HCC progression by serving as a molecular sponge for miR‑654‑3p to increase HDGF expression. Therefore, the MKLN1‑AS/miR‑654‑3p/HDGF axis may offer a novel target for the diagnosis, prognosis, prevention and treatment of HCC.