Apoptosis In Hepatocellular Carcinoma Cell Lines Research Articles

A Novel lncRNA lncRNA-4045 Promotes the Progression of Hepatocellular Carcinoma by Affecting the Expression of AKR1B10.

Long noncoding RNAs (lncRNAs) have been shown to be related to the occurrence and development of a variety of cancers including hepatocellular carcinoma (HCC). However, a large number of potential HCC-related lncRNAs remain undiscovered and are yet to be fully understood. Differentially expressed lncRNAs were first obtained from the tumor tissues and adjacent normal tissues of five HCC patients using high-throughput microarray chips. Then the expression levels of 10 differentially expressed lncRNAs were verified in 50 pairs of tissue samples from patients with HCC by quantitative real-time PCR (qRT-PCR). The oncogenic effects of lncRNA-4045 (ENST00000524045.6) in HCC cell lines were verified through a series of in vitro experiments including CCK-8 assay, plate clone formation assay, transwell assay, scratch assay, and flow cytometry. Subsequently, the potential target genes of lncRNA-4045 were predicted by bioinformatics analysis, fluorescence in situ hybridization assay, and RNA sequencing. The mechanism of lncRNA-4045 in HCC was explored by WB assay as well as rescue and enhancement experiments. The results from microarray chips showed 1,708 lncRNAs to have been significantly upregulated and 2725 lncRNAs to have been significantly downregulated in HCC tissues. Via validation in 50 HCC patients, a novel lncRNA lncRNA-4045 was found significantly upregulated in HCC tissues. Additionally, a series of in vitro experiments showed that lncRNA-4045 promoted the proliferation, invasion, and migration of HCC cell lines, and inhibited the apoptosis of HCC cell lines. The results of qRT-PCR in HCC tissues showed that the expression levels of AKR1B10 were significantly positively correlated with lncRNA-4045. LncRNA-4045 knockdown significantly down-regulated AKR1B10 protein expression, and overexpression of lncRNA-4045 led to significant up-regulation of AKR1B10 protein in HCC cell lines. Lastly, down-regulation of AKR1B10 could partially eliminate the enhancement of cell proliferation induced by lncRNA-4045 overexpression, while up-regulation of AKR1B10 was shown to enhance those effects. LncRNA-4045 may promote HCC via enhancement of the expression of AKR1B10 protein.

Comprehensive analysis of INTS family related to expression, prognosis, diagnosis and immune features in hepatocellular carcinoma

PurposeThe integrator subunit (INTS) family, a group exclusive to metazoans, participates in various biologic processes. However, their roles in hepatocellular carcinoma (HCC) remain largely unexplored. MethodsPublic databases were utilized to investigate the transcriptional and protein expression, and clinical relevance of the INTS family in HCC. Meanwhile, the effects of INTS13 knockdown and overexpression on cell proliferation and apoptosis were studied using HCC cell lines. ResultsThe mRNA expression of most INTSs were higher in tumor than normal tissues. Higher expression of INTS1/2/3/4/7/8/9/11/12/13 were correlated with poorer overall survival (OS) in Kaplan-Meier Survival Analysis. Multivariate analysis revealed higher level of INTS13 was an independent prognostic factor for shorter OS. Furthermore, genetic alteration of INTS3/6/7/8/9/10 were found in HCC patients and was associated with shorter disease-free survival and progression-free survival. INTS1/2/3/5/7/11/13/14 were associated with activation of tumor-induced immune response and immune infiltration in HCC. Knockdown of INTS13 inhibited cell proliferation and induced apoptosis in HCC cell lines, while overexpression of INTS13 had the opposite effect. ConclusionOur results indicate that INTS13 is an independent prognostic biomarker in HCC. Furthermore, INTS13 enhances cell proliferation and decreases cell apoptosis in HCC cell lines leading to a poorer OS in HCC patients.

In vitro and vivo anti-tumor activity and mechanisms of the new cryptotanshinone derivative 11 against hepatocellular carcinoma

Global burden of hepatocellular carcinoma (HCC) is increasing. Chemotherapy and immunotherapy are the prevailing options for therapy. Developing new therapeutic strategies for HCC patients is still highly desirable. Recent studies demonstrate that cryptotanshinone is capable of inhibiting tumor growth in HCC and induces antitumor immunity in vitro. In our previous research, we discovered a new cryptotanshinone derivative 11 as an effective immunoregulatory enzyme indoleamine 2, 3-dioxygenase 1 (IDO1) inhibitor. This study aims to evaluate its in vitro and in vivo antitumor activity against hepatocellular carcinoma. 11 displayed robust anti-proliferative activity against HCC cell lines and promoted apoptosis of HCC cell line through the mitochondrial-mediated apoptotic pathway. In H22 tumor-bearing mice models, 11 exhibited significant in vivo anti-tumor activity with different administration routes. And no obvious toxicity was observed. RNA-seq analysis demonstrated the differential expressed genes and alteration of key pathways associated with immune responses after administration of 11. Up-regulation of anti-tumor cytokines and down-regulation of cytokines that promote tumor growth were indicated and further validated. Our study demonstrates that 11 exhibits promising anti-tumor activity both in vitro and in vivo against hepatocellular carcinoma cancer. It is a lead compound for HCC immunotherapy and is worthy for further development.

The Effect of Silencing MiR-4270 on Apoptosis in HCC Cell Line

Background:: Hepatocellular carcinoma (HCC) is the most common type of cancer. Although HCC treatment has greatly improved over the past few decades, patient survival rates are still very low. Therefore, it is essential to find new treatments for HCC. Apoptosis has been shown to be the most effective in disrupting cancer growth. Improper functioning of proteins in apoptosis can lead to cancer growth. MicroRNAs (miRNAs) are key regulators in the development and progression of HCC. Objective:: Irregular expression of miRNAs involved in apoptosis signaling can lead to tumorigenesis. Therefore, we investigated the effect of the hsa-miR-4270 inhibitor on cell proliferation and apoptosis. Methods:: HepG2 cells were cultured at 37°C and 95% air. Transfection of HepG2 cells was performed by miR-4270 inhibitor and lipofectamine 2000. Cell proliferation of HepG2 cells was determined with MTT assay and different concentrations of miR-4270 specific inhibitors. DNA laddering assay was performed to evaluate the induction of apoptosis. Finally, the transcription level of genes involved in apoptosis, including BAX, BCL2, Caspase3, and p53, was measured by real-time RT-PCR. Results:: The results of MTT and DNA laddering assays showed that the miR-4270 inhibitor declined cell proliferation and induced apoptosis in HepG2 cells. Also, the results of quantitative real-time RT-PCR indicated an upregulation of transcription of BAX, p53 and Caspase3 genes and a decline in expression of BCL2 gene. Conclusion:: Taken together, we found hsa-miR-4270 inhibitor decreased cell proliferation and induced apoptosis in the HepG2 cell line, which can be used as a new therapeutic strategy for HCC patients.

Abstract 3959: Novel spliced isoform of the proteasome subunit ADRM1/Rpn13 promotes hepatocellular carcinoma (HCC) development through selective degradation of tumor suppressor p53

Abstract The Ubiquitin-Proteasome System (UPS) is the major pathway in eukaryotic cells that regulates intracellular protein degradation and turnover. Cumulative evidence has suggested that defects in the UPS machinery are involved in the pathogenesis of human diseases, including cancer. The proteasome-associated polyubiquitin receptor ADRM1 (also known as Rpn13) orchestrates the process of substrate recruitment with deubiquitination in the proteasome through its N-terminal ubiquitin-binding domain and C-terminal activation of deubiquitinating enzyme. Using long-read SMRT-seq to profile the RNA splicing landscape in hepatocellular carcinoma (HCC), we previously reported on an unannotated alternative spliced variant of ADRM1 in human hepatocellular carcinoma (HCC) (Hepatology 2019). This novel isoform exhibits an exon 9 skipping (ADRM1-ΔEx9) that resulted in an altered C-terminus of the protein. In this study, we undertook further investigations to characterize the detailed functional effects of ADRM1-ΔEx9 in HCC biology and the underlying mechanism. Initial study by junction-specific Taqman PCR assay showed that ADRM1-ΔEx9 is more frequently upregulated in HCC tumors than the canonical full-length counterpart (ADRM1-FL). There is an interchange between the two isoforms as tumor develops which underscores an isoform-switch in favor of HCC development. Indeed, our result showed that ADRM1-ΔEx9, but not ADRM1-FL, correlated significantly with inferior patient survival. Functionally, ADRM1-ΔEx9 knockdown profoundly suppressed proliferation by inducing spontaneous apoptosis in HCC cell lines and patient-derived HCC organoids. The corresponding effects were less apparent from ADRM1-FL knockdown. Consistently, overexpression of ADRM1-ΔEx9 in normal human liver organoids promoted pre-malignant features alongside increased in-vitro propagation time. Ubiquitin Proteome profiling revealed that ADRM1-ΔEx9 led to a reduced expression of the pivotal tumor suppressor p53. A parallel transcriptome also substantiated that ADRM1-ΔEx9 modulated genes involved in the p53 and apoptosis pathways. Collectively, our study demonstrated that the non-canonical spliced isoform ADRM1-ΔEx9 confers growth and pro-survival advantages in HCC through mediating selective degradation of tumor suppressor p53 protein. Citation Format: Yanmei Sun, Mingjing Xu, Ho Lee Wan, Alissa M. Wong, Kelvin K. Ng, Nathalie Wong. Novel spliced isoform of the proteasome subunit ADRM1/Rpn13 promotes hepatocellular carcinoma (HCC) development through selective degradation of tumor suppressor p53. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3959.

Molecular mechanism of Ganji Fang in the treatment of hepatocellular carcinoma based on network pharmacology, molecular docking and experimental verification technology.

Background: Hepatocellular carcinoma (HCC) is a malignant tumor harmful to human health. Ganji Fang (GJF) has good clinical efficacy in the treatment of HCC, but its mechanism is still unclear. Objective: The aim of this study was to investigate the mechanism of action of GJF in the treatment of HCC through network pharmacology, molecular docking and in vitro experiments. Methods: A series of network pharmacology methods were used to identify the potential targets and key pathways of GJF in the treatment of HCC. Then, molecular docking technology was used to explore the binding ability of key active ingredients and targets in GJF. Multiple external databases were used to validate the key targets. In in vitro experiments, we performed MTT assays, wound-healing assays, cell cycle assays, apoptosis assays and RT‒qPCR to verify the inhibitory effect of GJF on the Human hepatoma G2 (HepG2) cells. Result: A total of 162 bioactive components and 826 protein targets of GJF were screened, and 611 potential targets of HCC were identified. Finally, 63 possible targets of GJF acting on HCC were obtained. KEGG enrichment analyses showed that the top five pathways were the cell cycle, cellular senescence, p53 signaling pathway, PI3K/Akt signaling pathway, and progesterone-mediated oocyte maturation. Among them, we verified the PI3K/Akt signaling pathway. CCNE1, PKN1, CCND2, CDK4, EPHA2, FGFR3, CDK6, CDK2 and HSP90AAI were enriched in the PI3K/Akt pathway. The molecular docking results showed that the docking scores of eight active components of GJF with the two targets were all less than -5.0, indicating that they had certain binding activity. In vitro cell experiments showed that GJF could inhibit the proliferation and migration of HepG2 cells, block the cell cycle and induce apoptosis of HepG2 cells, which may be related to the PI3K/Akt signaling pathway. In summary, EPHA2 may be an important target of GJF in HCC, and pachymic acid may be an important critical active compound of GJF that exerts anticancer activity. Conclusion: In general, we demonstrated, for the first time, that the molecular mechanism of GJF in HCC may involve induction of G0/G1 phase cycle arrest through inhibition of the PI3K/Akt signaling pathway and promote apoptosis of hepatoma cell lines. This study provides a scientific basis for the subsequent clinical application of GJF and the in-depth study of its mechanism.

LncRNA SNHG6 promotes glycolysis reprogramming in hepatocellular carcinoma by stabilizing the BOP1 protein

ABSTRACT Metabolic reprogramming is an important feature in tumor progression. Long noncoding RNA’s (lncRNA) small nucleolar RNA host gene 6 (SNHG6) acts as a proto-oncogene in hepatocellular carcinoma (HCC) but its role in glycolysis is mostly unknown. The role of SNHG6 and Block of proliferation 1 (BOP1) on glycolysis is assessed by glucose uptake, lactate production, oxygen consumptive rate (OCR) and extracellular acidification rate (ECAR) and glycolytic enzyme levels. The regulatory effect of SNHG6 on BOP1 protein was confirmed by Western blotting, MS2 pull-down, RNA pull-down, and RIP assay. SNHG6 and BOP1 levels were increased in HCC tissues and cells. SNHG6 and BOP1 were prognostic factors in HCC patients and significantly correlated to TP53 mutant and tumor grade. SNHG6 promoted proliferation, inhibited apoptosis, enhanced glucose uptake and lactate production, decreased OCR, and increased ECAR in HCC cell lines. SNHG6 could bind the BOP1 protein and enhance its stability. BOP1 overexpression rescued the change of proliferation, apoptosis, and glycolysis in HCCLM3 and SMMC-7721 cells. Our data indicate that SNHG6 accelerates proliferation and glycolysis and inhibits the apoptosis of HCC cell lines by binding the BOP1 protein and enhancing its stability. Both SNHG6 and BOP1 are promising prognostic and therapeutic markers in HCC.

Parthenolide and arsenic trioxide co-trigger autophagy-accompanied apoptosis in hepatocellular carcinoma cells.

Although arsenic trioxide (ATO) shows a strong anti-tumor effect in the treatment of acute promyelocytic leukemia, it does not benefit patients with hepatocellular carcinoma (HCC). Thus, combination therapy is proposed to enhance the efficacy of ATO. Parthenolide (PTL), a natural compound, selectively eradicates cancer cells and cancer stem cells with no toxicity to normal cells. In this study, we chose PTL and ATO in combination and found that nontoxic dosage of PTL and ATO co-treatment can synergistically inhibit the in vitro and in vivo proliferation activity of HCC cells through suppressing stemness and self-renewal ability and inducing mitochondria-dependent apoptosis. More importantly, USP7-HUWE1-p53 pathway is involved in PTL enhancing ATO-induced apoptosis of HCC cell lines. Meanwhile, accompanied by induction of apoptosis, PTL and ATO evoke autophagic activity via inhibiting PI3K/Akt/mTOR pathway, and consciously controlling autophagy can improve the anti-HCC efficacy of a combination of PTL and ATO. In short, our conclusion represents a novel promising approach to the treatment of HCC.

LOXL3-promoted hepatocellular carcinoma progression via promotion of Snail1/USP4-mediated epithelial-mesenchymal transition.

Lysyl-oxidase-like 3 (LOXL3) was reported to be essential in epithelial-mesenchymal transition (EMT) of cancers. However, the role of LOXL3 in hepatocellular carcinoma (HCC) remained unclear. In this study, we explored clinical significance, biological functions, and regulatory mechanisms of LOXL3 in HCC. Our study found that LOXL3 expression was markedly associated with the tumor size and clinical stage of HCC, and it was highly expressed in tumor tissues of metastatic HCC patients. High expression of LOXL3 predicted a poor prognosis of HCC. TGF-β1 treatment elevated LOXL3 protein expression and cell invasion, and reduced cell apoptosis in HCC cell lines (SMMC-7721 and Huh-7), while downregulation of LOXL3 reversed the promotive effects of TGF-β1 treatment on LOXL3 protein expression and cell invasion, and the inhibitory effect on cell apoptosis. Mechanistically, LOXL3 interacted with snail family transcriptional repressor 1 (Snail1) through STRING database and RIP assay, and Snail1 bound to ubiquitin-specific peptidase 4 (USP4) promoter by JASPAR database, luciferase reporter gene and Co-IP assays. Overexpression of USP4 reversed the inhibitory effect of LOXL3 silence on EMT in HCC cells through deubiquitinating and stabilizing the expression of Snail1. Moreover, LOXL3-promoted HCC EMT through Wnt/β-catenin/Snail1 signaling pathway. In vivo study revealed that silence of LOXL3-inhibited HCC tumor growth. In conclusion, LOXL3 silence inhibited HCC invasion and EMT through Snail1/USP4-mediated circulation loop and Wnt/β-catenin signaling pathway.

LncRNA NEAT1 sponges miR-214 to promoted tumor growth in hepatocellular carcinoma.

Live cancer is the sixth most prevalent diagnosed malignant tumor and the fourth leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the main histological type of liver cancer. Here, we attempt to evaluate the role of long non coding RNA NEAT1 in HCC, and explore its potential mechanism in this disease. Initially, we detected the expression of NEAT1 in HCC cell lines (SMMC-7721 and Huh7 cells) using qRT-PCR. Then we transfected si-NC or si-NEAT1 into SMMC-7721 and Huh7 cells by RNA interference. CCK-8 assay, transwell assay, flow cytometry, qRT-PCR and western blotting were used to evaluate the role of NEAT1 in the biological behavior of SMMC-7721 and Huh7 cells. The rescue experiment, RIP assay and MeRIP were devoted to the underlying mechanism. NEAT1 expression level was significantly elevated in SMMC-7721 and Huh7 cells. Knockdown of NEAT1 inhibited proliferation and migration, induced apoptosis of HCC cell lines. NEAT1 serves as a sponge for miR-214. Besides, PSMB8 was a direct target of miR-214. Furthermore, ALKBH5 could up-regulate NEAT1 expression by inhibiting m6A enrichment. ALKBH5-induced NEAT1 promoted cell proliferation and migration of HCC by sponging miR-214 in vitro, which may provide a potential therapeutic target for HCC.

Cyclin dependent kinase 9 inhibition as a potential treatment for hepatocellular carcinoma.

425 Background: Composite cyclin dependent kinase (CDK) inhibition has shown potential as a treatment for hepatocellular carcinoma (HCC) in preclinical studies. We tested whether the specific inhibition of CDK9 was effective against HCC. Methods: The effects of two specific CDK9 inhibitors, BAY1143572 and AZD4573, on cell viability and apoptosis in HCC cell lines were examined. We tested the in vivo efficacy of CDK9 inhibition in mouse xenograft models of HuH7 human HCC cells and in an orthotopic model of BNL mouse HCC cells. Overexpression and knockdown of CDK9 were performed to confirm the efficacy of CDK9 inhibition. Results: Both BAY1143572 and AZD4573 exhibited potent antiproliferative activities in HCC cell lines including HuH7, HLE, and HepG2, regardless of the levels of c-myc expression while inhibiting the downstream signals of CDK9, such as the phosphorylation of RNA polymerase II. These 2 CDK9 inhibitors induced apoptosis in HCC cells and reduced the expression of antiapoptotic proteins such as myeloid cell leukemia-1, survivin, BimEL, and the X-linked inhibitor of apoptosis protein. Reduction of CDK9 expression through siRNA knockdown also reduced the phosphorylation of RNA polymerase II and the colony formations of HuH7 and HLE cells. In the xenograft studies, mice receiving either CDK9 inhibitor exhibited a significantly lower tumor growth rate than did the mice receiving vehicles. In the orthotopic model, the HCC growth in mice receiving BAY1143572 also tended to be slower than that in the control group. Overexpression of CDK9 in HuH7 cells reduced the efficacy of both CDK9 inhibitors. Conclusions: We demonstrated the in vitro and in vivo activity of CDK9 inhibition on multiple HCC cell lines. Our data support further clinical development of CDK9 inhibitors as a treatment for HCC.

Melatonin Reduces Apoptosis Resistance of Hepatocellular Carcinoma Cells by Inhibiting BMAL1

Purpose:This study aimed to explore the role and molecular mechanism of brain and muscle ARNT-like protein 1 (BMAL1) in hepatocellular carcinoma (HCC), and the effect of melatonin on BMAL1 expression and apoptosis of HCC cells.Methods:We mainly used immunohistochemistry, western blot, cck-8 assays, flow cytometry, wound-healing assay, transwell assay, and RT-qPCR for this research.Results:The expression of BMAL1 protein was frequently up-regulated in the tissues and cell lines of HCC patients. Its high expression was significantly associated with tumor size, tumor differentiation degree, and shorter survival. In addition, cell functional experiments showed that BMAL1 could promote proliferation and migration, and inhibit apoptosis in HCC cell lines. Furthermore, the expression of BMAL1 was related to the endoplasmic reticulum stress (ERS) level. Knockdown of BMAL1 could inhibit the expression of ERS-related protein, while overexpression of BMAL1 led to the increase of ERS-related protein’s level. Low concentration of ERS led to the increase of BMAL1, and a certain degree of ERS in turn inhibited the expression of BMAL1. Melatonin promoted apoptosis of hepatoma cells by inhibiting the expression of BMAL1.Conclusion:BMAL1 plays a key role in HCC patients’ survival and tumor growth, which may be related to its interaction with ERS-related pathways. Melatonin can regulate ERS-related apoptosis resistance by inhibiting BMAL1 expression, promoting apoptosis of HCC cells.

Role of lncRNA LINC01194 in hepatocellular carcinoma via the miR-655-3p/SMAD family member 5 axis

ABSTRACT Long non-coding RNAs (lncRNAs) are involved in developing hepatocellular carcinoma (HCC). The present study explored the role of lncRNA LINC01194, which is upregulated in HCC tissues and might be a vital regulator in HCC progression. Levels of LINC01194, microRNA (miR)-655-3p, and SMAD family member 5 (SMAD5) were assessed using reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). The bioactivity of Huh-7 cells was assessed using cell counting kit-8 and transwell assays and flow cytometry. Western blotting was conducted to measure the expression of invasion- and apoptosis-related proteins. The relationships between lncRNA LINC01194 and miR-655-3p, and miR-655-3p and SMAD5 were predicted using StarBase and TargetScan, and further verified using a dual-luciferase reporter assay. LINC01194 was overexpressed in HCC cells and in clinical samples. ILINC01194 silencing suppressed proliferation and migration; however, it promoted apoptosis in HCC cell lines. We also confirmed that miR-655-3p could bind to LINC01194, and miR-655-3p was downregulated in HCC. The upregulation of miR-655-3p suppressed HCC cell invasion and migration, and enhanced the number of apoptotic cells. SMAD5, which was overexpressed in HCC cell lines, was directly targeted by miR-655-3p. Therefore, LINC01194 promoted HCC development by decreasing miR-655-3p expression and may serve as a promising therapeutic target for HCC patients.

Induction of Apoptosis in Hepatocellular Carcinoma Cell Lines by Novel Indolylacrylamide Derivatives: Synthesis and Biological Evaluation.

Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer and one of the leading causes of cancer associated death worldwide. This is due to the highly resistant nature of this malignancy and the lack of effective treatment options for advanced stage HCC patients. The hyperactivity of PI3K/Akt and Ras/Raf/MEK/ERK signaling pathways contribute to the cancer progression, survival, motility, and resistance mechanisms, and the interaction of these two pathways are responsible for the regulation of cancer cell growth and development. Therefore, it is vital to design and develop novel therapeutic options for HCC treatment targeting these hyperactive pathways. For this purpose, novel series of trans-indole-3-ylacrylamide derivatives originated from the lead compound, 3-(1H-indole-3-yl)-N-(3,4,5-trimethoxyphenyl)acrylamide, have been synthesized and analyzed for their bioactivity on cancer cells along with the lead compound. Based on the initial screening, the most potent compounds were selected to elucidate their effects on cellular signaling activity of HCC cell lines. Cell cycle analysis, immunofluorescence, and Western blot analysis revealed that lead compound and (E)-N-(4-tert-butylphenyl)-3-(1H-indole-3-yl)acrylamide induced cell cycle arrest at the G2/M phase, enhanced chromatin condensation and PARP-cleavage, addressing induction of apoptotic cell death. Additionally, these compounds decreased the activity of ERK signaling pathway, where phosphorylated ERK1/2 and c-Jun protein levels diminished significantly. Relevant to these findings, the lead compound was able to inhibit tubulin polymerization as well. To conclude, the novel trans-indole-3-ylacrylamide derivatives inhibit one of the critical pathways associated with HCC which results in cell cycle arrest and apoptosis in HCC cell lines.

LINC00657 knockdown suppresses hepatocellular carcinoma progression by sponging miR-424 to regulate PD-L1 expression.

Hepatocellular carcinoma (HCC) is the sixth most commonly diagnosed malignant tumor and the fourth leading cause of cancer-related deaths worldwide. As a novel non-coding RNA, LINC00657 was firstly identified as an oncogenic role in breast cancer. However, few research focus on the effect of LINC00657 on the progression of HCC. The purpose of this study was to investigate the effect of LINC00657 on HCC tissues and cells, and further explore the potential mechanism. We first measured the expression of LINC00657 in HCC tissues and cell lines using qRT-PCR. Next we established LINC00657 knockdown in HCC cells. CCK-8 assay, cell invasion assay, flow cytometry analysis, qRT-PCR and western blotting were applied to assess the role of LINC00657 knockdown in the biological behavior of HCC cells. The bioinformatics analysis and the rescue experiment were devoted to the underlying mechanism. LINC00657 was remarkably overexpressed in HCC tissues and cell lines, associated with poor prognosis. LINC00657 knockdown repressed cell proliferation and invasion, promoted cell apoptosis of HCC cell lines. The bioinformatics analysis showed LINC00657 sponged miR-424 as a ceRNA. Besides, PD-L1 mimic rescued the suppression of si-LINC00657 in the biological behavior of HCC cells. In a word, we observed LINC00657 regulated PD-L1 expression by sponging miR-424, thus affecting the developments of hepatocellular carcinoma. These findings LINC00657 may provide new evidence for therapeutic application in hepatocellular carcinoma.

Discovery of VEGFR-2 inhibitors exerting significant anticancer activity against CD44+ and CD133+ cancer stem cells (CSCs): Reversal of TGF-β induced epithelial-mesenchymal transition (EMT) in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a malignancy characterized by neoangiogenesis, which is an augmented production of proangiogenic factors by the tumor and its adjacent infected cells. These dysregulated angiogenic factors are the therapeutic targets in anti-angiogenic drug development. The signaling pathway of vascular endothelial growth factor (VEGF)/VEGFR-2 is crucial for controlling the angiogenic responses in endothelial cells (ECs). In this study, we carried out a rational drug design approach wherein we have identified the novel orally bioavailable compound VS 8 as a potent VEGFR-2 inhibitor, which remarkably suppresses hVEGF and hVEGFR-2 expression in HUVECs and exhibits significant anti-angiogenic effects in CAM assay. Besides, VS 8 significantly induces apoptosis in HCC cell line (Hep G2). Later we examined its effectiveness against CD44+ and CD133+ CSCs. Here, VS 8 was found to be active against CSCs, and adequate for the cessation of the cell cycle at 'G0/G1' and 'S' phase in CD44+ and CD133+ CSCs respectively. Factually, transforming growth factor-β (TGF-β) stimulated epithelial-mesenchymal transition (EMT) induces invasion and migration of HCC cells, which results in the metastasis. Therefore, we studied the effect of VS 8 on EMT markers using flow cytometry, which suggested that VS 8 significantly upregulates E-cadherin (epithelial biomarker) and downregulates vimentin (mesenchymal biomarker). Further, VS 8 downregulates the expression of EMT-inducing transcription factors (EMT-TFs), i.e., SNAIL. Altogether, our findings indicate that VS 8 could be a promising drug candidate for cancer therapy.

\u03b1-Lipoic acid induces Endoplasmic Reticulum stress-mediated apoptosis in hepatoma cells

Hepatocellular carcinoma (HCC) is the most common liver cancer and a major cause of adult death. The current treatments for HCC suffer from drug resistance and poor prognosis; therefore, novel therapeutic agents are urgently needed. Phytochemicals have been proposed to treat a range of cancers. Among them, α-lipoic acid (α-LA), a naturally synthesized antioxidant found in various dietary animal and plant sources, prevents oxidant-mediated cell death in normal cells while inducing apoptosis in several cancer cell lines. Previously, we demonstrated that the treatment of hepatoma cells with α-LA induced apoptosis, which was preceded by the generation of reactive oxygen species (ROS) and activation of the p53 protein, a known inducer of mitochondria-mediated apoptosis. Several studies have shown that ROS-induced apoptosis is associated with endoplasmic reticulum (ER) stress and Unfolded Protein Response (UPR) activation. Herein, we investigated if α-LA-induced apoptosis in hepatoma cell lines was ER stress- and UPR-mediated by gene expression profiling analyses. UPR and ER stress pathways were the most up-regulated after treatment with α-LA. This finding, which has been confirmed by expression analyses of ER- and UPR-associated proteins, provides a better understanding of the molecular mechanisms behind the anti-tumoral action of α-LA on hepatoma cells.

Synergistic antitumor activity of sorafenib and artesunate in hepatocellular carcinoma cells.

Sorafenib is currently the standard chemotherapy drug for treatment of advanced hepatocellular carcinoma (HCC). But its efficacy requires improvement, it is imperative to seek therapeutic strategies that combine sorafenib with other anticancer agents. In this study we investigated the synergistic anticancer effect of combining sorafenib and artesunate, an anti-malaria drug derivative, against HCC in vitro and in vivo. We first showed that artesunate (1-100 μM) alone dose-dependently inhibited the proliferation of five HCC cell lines tested with IC50 values of around 100 μM. Artesunate treatment dose-dependently increased the ROS level in both HuH7 and Hep3B cells; addition of NAC significantly ameliorated the antiproliferation effect of artesunate against HuH7 and Hep3B cells. Then we demonstrated that combination of sorafenib and artesunate exerted synergistic antiproliferation effect and induced synergistic apoptosis in HCC cell lines. In nude mice bearing Hep3B xenografts, combined administration of sorafenib and artesunate significantly enhanced the suppression on tumor growth. We further revealed that sorafenib dose-dependently decreased the levels of p-ERK and p-STAT3, whereas artesunate markedly increased the levels of p-ERK and p-STAT3 in HuH7 and Hep3B cells. When used in combination, sorafenib abolished artesunate-elevated levels of p-STAT3 and p-ERK. Moreover, pharmacological inhibition of ERK by inhibitor PD0325901 or STAT3 by inhibitor Stattic markedly enhanced the anticancer activity of artesunate, suggesting that suppression of ERK and STAT3 signaling by sorafenib contributes to the synergistic anticancer activity against HCC caused by combination of sorafenib and artesunate. Taken together, our results provide an evidence for possible use of sorafenib plus artesunate or artemisinin analogs for treatment of HCC in the future.

Trefoil Factor Family 1 Inhibits the Development of Hepatocellular Carcinoma by Regulating β-Catenin Activation.

Recent studies have suggested that trefoil factor family 1 (TFF1) functions as a tumor suppressor in gastric and pancreatic carcinogenesis. To investigate the role of TFF1 in hepatocarcinogenesis, we performed immunohistochemical staining of surgically resected human liver samples, transfected a TFF1 expression vector into hepatocellular carcinoma (HCC) cell lines, and employed a mouse model of spontaneous HCC development (albumin-cyclization recombination/Lox-Stop-Lox sequence-Kirsten rat sarcoma viral oncogene homologG12D [KC]); the model mouse strain was bred with a TFF1-knockout mouse strain to generate a TFF1-deficient HCC mouse model (KC/TFF1-/- ). TFF1 expression was found in some human samples with HCC. Interestingly, TFF1-positive cancer cells showed a staining pattern contradictory to that of proliferating cell nuclear antigen, and aberrant DNA hypermethylation in TFF1 promoter lesions was detected in HCC samples, indicating the tumor-suppressive role of TFF1. In vitro, induction of TFF1 expression resulted in impaired proliferative activity and enhanced apoptosis in HCC cell lines (HuH7, HepG2, and HLE). These anticancer effects of TFF1 were accompanied by the loss of nuclear β-catenin expression, indicating inactivation of the β-catenin signaling pathway by TFF1. In vivo, TFF1 deficiency in KC mice accelerated the early development and growth of HCC, resulting in poor survival rates. In addition, immunohistochemistry revealed that the amount of nuclear-localized β-catenin was significantly higher in KC/TFF1-/- mice than in KC mice and that human HCC tissue showed contradictory expression patterns for β-catenin and TFF1, confirming the in vitro observations. TFF1 might function as a tumor suppressor that inhibits the development of HCC by regulating β-catenin activity.

Homeobox B5 suppression attenuates proliferation and elevates apoptosis in hepatoma cell lines through ERK/MDM2 signalling.

Homeobox B5 (HOXB5), a member of the HOX gene family, is an important gene in tumourigenesis. However, its role in hepatocellular carcinoma (HCC) cell proliferation and apoptosis remains unclear. In this study, we investigated the role and regulation mechanism of HOXB5 in HCC cell lines Hep3B and LM6. The data indicated high expression of HOXB5 in HCC tissues and cell lines. In HCC cells, inhibition of HOXB5 by transfection with HOXB5 siRNA significantly constrained cell viability, and Bcl-2 levels, and it increased cell apoptosis, cytochrome c levels, BAX levels, and caspase-3 activity. On the contrary, HOXB5 overexpression increased proliferation and Bcl-2 levels but inhibited BAX levels and caspase-3 activity in these cells. HOXB5 downregulation attenuated activation of extracellular signal-regulated kinase (ERK) and expression of the murine double minute 2 (MDM2) oncogene. Incubation with the ERK activator, phorbol 12-myristate 13-acetate (40μmol/L), for 12hours reversed the effects of HOXB5 inhibition on MDM2 expression, cell proliferation, and apoptosis in HCC cells. Overall, this study demonstrated that HOXB5 inhibition regulated MDM2 expression by controlling ERK activation and that it modulated proliferation and apoptosis in HCC cells.