Apoptosis In Human Hepatocellular Carcinoma Cells Research Articles

Prohibitin 1 inhibits cell proliferation and induces apoptosis via the p53-mediated mitochondrial pathway in vitro.

Prohibitin 1 (PHB1) has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed, and it participates in a variety of essential cellular functions, including apoptosis, cell cycle regulation, proliferation, and survival. Emerging evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma (HCC). However, the role of PHB1 in HCC is controversial. To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in vitro. HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria; then, PHB1 levels in the sera and liver tissues of these participates were determined using ELISA, RT-PCR, and immunohistochemistry. Human HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA (shRNA-PHB1) for 24-72 h. Cell proliferation was analysed with an MTT assay. Cell cycle progression and apoptosis were analysed using flow cytometry (FACS). The mRNA and protein expression levels of the cell cycle-related molecules p21, Cyclin A2, Cyclin E1, and CDK2 and the cell apoptosis-related molecules cytochrome C (Cyt C), p53, Bcl-2, Bax, caspase 3, and caspase 9 were measured by real-time PCR and Western blot, respectively. Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals, and decreased PHB1 was positively correlated with low differentiation, TNM stage III-IV, and alpha-fetoprotein ≥ 400 μg/L. Overexpression of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent manner. FACS revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced apoptosis. The proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compared with untreated control and empty vector-transfected cells. The percentage of apoptotic HepG2 cells that were transfected with pEGFP-PHB1 was 15.41% ± 1.06%, which was significantly greater than that of apoptotic control cells (3.65% ± 0.85%, P < 0.01) and empty vector-transfected cells (4.21% ± 0.52%, P < 0.01). Similar results were obtained with SMMC-7721 cells. Furthermore, the mRNA and protein expression levels of p53, p21, Bax, caspase 3, and caspase 9 were increased while the mRNA and protein expression levels of Cyclin A2, Cyclin E1, CDK2, and Bcl-2 were decreased when PHB1 was overexpressed in human HCC cells. However, when PHB1 was upregulated in human HCC cells, Cyt C expression levels were increased in the cytosol and decreased in the mitochondria, which indicated that Cyt C had been released into the cytosol. Conversely, these effects were reversed when PHB1 was knocked down. PHB1 inhibits human HCC cell viability by arresting the cell cycle and inducing cell apoptosis via activation of the p53-mediated mitochondrial pathway.

Identification of a Difluorinated Alkoxy Sulfonyl Chloride as a Novel Antitumor Agent for Hepatocellular Carcinoma through Activating Fumarate Hydratase Activity.

Fenofibrate is known as a lipid-lowering drug. Although previous studies have reported that fenofibrate exhibits potential antitumor activities, IC50 values of fenofibrate could be as high as 200 μM. Therefore, we investigated the antitumor activities of six synthesized fenofibrate derivatives. We discovered that one compound, SIOC-XJC-SF02, showed significant antiproliferative activity on human hepatocellular carcinoma (HCC) HCCLM3 cells and HepG2 cells (the IC50 values were 4.011 μM and 10.908 μM, respectively). We also found this compound could inhibit the migration of human HCC cells. Transmission electron microscope and flow cytometry assays demonstrated that this compound could induce apoptosis of human HCC cells. The potential binding sites of this compound acting on human HCC cells were identified by mass spectrometry-cellular thermal shift assay (MS-CETSA). Molecular docking, Western blot, and enzyme activity assay-validated binding sites in human HCC cells. The results showed that fumarate hydratase may be a potential binding site of this compound, exerting antitumor effects. A xenograft model in nude mice demonstrated the anti-liver cancer activity and the mechanism of action of this compound. These findings indicated that the antitumor effect of this compound may act via activating fumarate hydratase, and this compound may be a promising antitumor candidate for further investigation.

Euphorbiasteroid Induces Apoptosis as Well as Autophagy through Modulating SHP-1/STAT3 Pathway in Hepatocellular Carcinoma Cells.

Euphorbiasteroid (EPBS) has gained attention for its activity against human lung cancer and sarcoma; however, its impact on hepatocellular carcinoma has not yet been elucidated. Here, we investigated the cytotoxic effect of EPBS on human hepatocellular carcinoma (HCC) cells. We found that EPBS induced both apoptosis and autophagy in HCC cells. Additionally, we observed that EPBS treatment suppressed the constitutive as well as the inducible activation of a signal transducer and activator of transcription 3 (STAT3) protein expression. Moreover, EPBS promoted the expression of SHP-1 protein and the production of reactive oxidative stress (ROS). Furthermore, the knockdown of SHP-1 by siRNA transfection reversed the effects of EPBS, which have inductive effects related to apoptosis and autophagy. Therefore, EPBS can potentially function as an anti-cancer agent by inducing apoptosis and autophagy when targeting the SHP-1/STAT3 pathway.

Depletion of circ_0088046 suppressed cell growth and motility of hepatocellular carcinoma via circ_0088046-miR-1299-RTKN2 ceRNA pathway.

Circular RNAs (circRNAs) have been verified to be important modulators and therapeutic targets of human hepatocellular carcinoma (HCC). This study aims to explore the role and mechanism of circ_0088046 in HCC progression. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot and immunohistochemistry assays were used to detect the mRNA and protein expression of circ_0088046, miR-1299, Rhotekin 2 (RTKN2), Bax, Bcl-2, E-cadherin and Ki-67. Cell proliferation was investigated by 5-Ethynyl-2'-deoxyuridine (EdU) assay and cell colony formation assay. Cell apoptosis rate was measured by flow cytometry. Transwell migration and invasion assays were adopted to assess cell migration and invasion. The molecular target relationship between miR-1299 and circ_0088046 or RTKN2 were analysed by dual-luciferase reporter assay and RNA immunoprecipitation assay. An animal experiment was conducted to demonstrate the effect of circ_0088046 on tumour formation in vivo. High levels of circ_0088046 and RTKN2, and low levels of miR-1299 were displayed in HCC tissues and cells. Circ_0088046 absence repressed cell proliferation, migration and invasion, but boosted apoptosis of HCC cells. MiR-1299 was a target of circ_0088046 and miR-1299 inhibitor restored circ_0088046 silencing-mediated inhibitory impacts on HCC cell malignancy. MiR-1299 could directly target RTKN2, and overexpressed RTKN2 rescued the suppressive effects caused by miR-1299 mimic. In addition, circ_0088046 silencing constrained tumour formation in vivo. Circ_0088046 contributed to HCC cell malignancy via modulating the miR-1299/RTKN2 axis.

(2E)-1-(2,4,6-Trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one, a Chalcone Derivative, Promotes Apoptosis by Suppressing RAS-ERK and AKT/FOXO3a Pathways in Hepatocellular Carcinoma Cells.

Liver cancer is an extremely common cancer with the highest mortality rate and poor prognosis. Owing to their low systemic toxicity and few side effects, natural compounds may provide better therapeutic effects for patients. (2E)-1-(2,4,6-trimethoxyphenyl)-3-(4-chlorophenyl)prop-2-en-1-one (TMOCC), a chalcone derivative, exhibits cytotoxicity towards many tumor cells. However, the anticancer mechanism of TMOCC has not been elucidated in human hepatocellular carcinoma (HCC). Cell Counting Kit-8 and colony formation assays were used to evaluate the effects of TMOCC on viability and proliferation. Mitochondrial transmembrane potential and flow cytometry assays were used to detect apoptosis. The expression levels of proteins related to apoptosis, the RAS-ERK and AKT/FOXO3a signaling pathways were assessed using western blot. Potential targets of TMOCC were detected using molecular docking analysis. TMOCC inhibited viability and proliferation, and induced the loss of mitochondrial transmembrane potential, apoptosis and DNA double-strand breaks in both HCC cells. The RAS-ERK and AKT/FOXO3a signaling pathways were suppressed by TMOCC. Finally, ERK1, PARP-1, and BAX were identified as potential targets of TMOCC. Taken together, our results show that TMOCC promotes apoptosis by suppressing the RAS-ERK and AKT/FOXO3a signaling pathways. TMOCC may be a potential multi-target compound that is effective against liver cancer.

Polysaccharides from Hemerocallis citrina Baroni Inhibit the Growth of Hepatocellular Carcinoma Cells by Regulating the Wnt/β-Catenin Pathway

Hemerocallis citrina Baroni is an edible plant with anti-inflammatory, antidepressant, and anticancer activities. However, studies on H. citrina polysaccharides are limited. In this study, a polysaccharide named HcBPS2 was isolated and purified from H. citrina. Monosaccharide component analysis showed that HcBPS2 was composed of rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid. Notably, HcBPS2 significantly inhibited human hepatoma cell proliferation, but had little effect on human normal liver cells (HL-7702). Mechanism investigations indicated HcBPS2 suppressed human hepatoma cell growth through the induction of G2/M phase arrest and mitochondria-dependent apoptosis in human hepatoma cells. In addition, the data revealed that HcBPS2 treatment led to the inactivation of Wnt/β-catenin signaling, which then gave rise to cell cycle arrest and apoptosis in human hepatoma cancer cells. Collectively, these findings suggested that HcBPS2 may serve as a therapeutic agent against liver cancer.

Usenamine A induces apoptosis and autophagic cell death of human hepatoma cells via interference with the Myosin-9/actin-dependent cytoskeleton remodeling

BackgroundHepatocellular carcinoma (HCC) is a major cause of cancer-associated mortality worldwide. Myosin-9′s role in HCC and the anti-HCC effect of the drugs targeting Myosin-9 remain poorly understood so far. Candidate antitumor agents obtained from natural products have attracted worldwide attention. Usenamine A is a novel product, which was first extracted in our laboratory from the lichen Usnea longissima. According to published reports, usenamine A exhibits good antitumor activity, while the mechanisms underlying its antitumor effects remain to be elucidated. PurposeThe present study investigated the anti-hepatoma effect of usenamine A and the underlying molecular mechanisms, along with evaluating the therapeutic potential of targeting Myosin-9 in HCC. MethodsThe CCK-8, Hoechst staining, and FACS assays were conducted in the present study to investigate how usenamine A affected the growth and apoptosis of human hepatoma cells. Moreover, TEM, acridine orange staining, and immunofluorescence assay were performed to explore the induction of autophagy by usenamine A in human hepatoma cells. The usenamine A-mediated regulation of protein expression in human hepatoma cells was analyzed using immunoblotting. MS analysis, SPR assay, CETSA, and molecular modeling were performed to identify the direct target of usenamine A. Immunofluorescence assay and co-immunoprecipitation assay were conducted to determine whether usenamine A affected the interaction between Myosin-9 and the actin present in human hepatoma cells. In addition, the anti-hepatoma effect of usenamine A was investigated in vivo using a xenograft tumor model and the IHC analysis. ResultsThe present study initially revealed that usenamine A could suppress the proliferation of HepG2 and SK-HEP-1 cells (hepatoma cell lines). Furthermore, usenamine A induced cell apoptosis via the activation of caspase-3. In addition, usenamine A enhanced autophagy. Moreover, usenamine A administration could dramatically suppress the carcinogenic ability of HepG2 cells, as evidenced by the nude mouse xenograft tumor model. Importantly, it was initially revealed that Myosin-9 was a direct target of usenamine A. Usenamine A could block cytoskeleton remodeling through the disruption of the interaction between Myosin-9 and actin. Myosin-9 participated in suppressing proliferation while inducing apoptosis and autophagy in response to treatment with usenamine A. In addition, Myosin-9 was revealed as a potential oncogene in HCC. ConclusionsUsenamine A was initially revealed to suppress human hepatoma cells growth by interfering with the Myosin-9/actin-dependent cytoskeleton remodeling through the direct targeting of Myosin-9. Myosin-9 is, therefore, a promising candidate target for HCC treatment, while usenamine A may be utilized as a possible anti-HCC therapeutic, particularly in the treatment of HCC with aberrant Myosin-9.

MicroRNA 424-5p promotes the sensitivity of hepatocellular carcinoma cells to sorafenib by targeting Kinesin family member 23

Objective: To explore the effect of MicroRNA 424-5p/Kinesin family member 23(miR-424-5p/KIF23)axis on the malignant phenotype of hepatoma cells and its sensitivity of sorafenib. Methods: Real-time quantitative reverse PCR(qRT-PCR) and/or Western blot were used to detect the expression of miR-424-5p and KIF23 in liver cancer tissues and paracancerous tissues, human hepatocellular carcinoma(HCC) cells HepG2 and normal hepatocyte LO2. HepG2 cells transfected with miR-424-5p mimic and miR-424-5p mimic NC were respectively defined as miR-424-5p mimic group and mimic NC group, HepG2 cells transfected with KIF23 overexpression vector pcDNA3.1-KIF23 or empty vector pcDNA3.1 respectively were defined as OE-KIF23 group and Vector group, and HepG2 cells co-transfected with miR-424-5p mimic and overexpression vector pcDNA3.1-KIF23 were defined as mimic+OE-KIF23 group: The KIF23-3'UTR wild-type vector (KIF23-WT) and the mutant vector (KIF23-MT) were co-transfected with miR-424-5p micic and mimic NC, respectively, and the targeting relationship between miR-424-5p and KIF23 was verified by dual-luciferase reporting experiments. The cell counting Kit-8 (CCK-8) was used to detect HepG2 cell proliferation and sensitivity to sorafenib. Flow cytometry was used to assess apoptosis in HepG2 cells. Transwell and scratch experiments were used to detect HepG2 cell migration and invasion capabilities. Intergroup data were compared using t-tests or analysis of variance. Results: Compared with the paracancerous tissue and normal hepatocytes, miR-424-5p in the HCC tissue and hepatocellular cells was significantly down-regulated (the relative expression was 0.604±0.121, 0.585±0.064), and KIF23 was significantly up-regulated (the relative expression was 5.451±1.834, 2.482±0.545), P<0.05. miR-424-5p mimic can inhibit the proliferation, migration and invasion of HCC cells and promote apoptosis of HCC cells (P<0.05). Overexpression of KIF23 can promote the proliferation, migration and invasion of HCC cells and inhibit apoptosis of HCC cells (P<0.05). The luciferase activity of HepG2 cells in the mimic and KIF23-WT co-transfection groups was significantly reduced compared with HepG2 cells in the mimic NC and KIF23-WT co-transfection groups (the relative fluorescence intensities were 3.668±0.091 and 2.629±0.056, respectively, P<0.05),however, there was no significant comparison between the luciferase activity of cells in the mimic and KIF23-MT co-transfection groups compared with those in the mimic NC and KIF23-MT co-transfection groups. miR-424-5p mimic can reverse the role of overexpression of KIF23 in promoting the ability of HCC cells to proliferate, migrate and invade (P<0.05). The inhibition rates of sorafenib on HepG2 cells in the mimic+OE-KIF23 group and the OE-KIF23 group were 47.491%±3.863% and 36.246%±6.063% (t=3.027, P<0.05). Conclusion: miR-424-5p can inhibit the proliferation, migration and invasion of HCC cells and can increase the sensitivity of HCC cells to sorafenib by targeting the expression level of KIF23.

Ginsenoside compound K induces mitochondrial apoptosis in human hepatoma cells through Bclaf1-mediated modulation of ERK signaling

ABSTRACT Compound K (CK) is the metabolite and final active ingredient of diol-type ginsenosides. In this study, we investigated the effect of CK on mitochondrial apoptosis in SMMC-7721 and BEL-7404 cells and the regulatory mechanism through in vitro and in vivo experiments. The results demonstrated that CK inhibited Hepatocellular carcinoma (HCC) cells proliferation and arrested the cells in G0/G1 phase. CK induces mitochondrial apoptosis in HCC cells and inhibited p-ERK expression. Bcl-2 associated transcription factor 1 (Bclaf1) was distributed in the nucleus and cytoplasm, and CK inhibited its expression. Treatment of a nude mouse xenograft model bearing SMMC-7721 cells with CK decreased the expression of Bclaf1, p-ERK, and Bcl-2 but increased that of Bax. In summary, ginsenoside CK downregulated Bclaf1 expression, inhibited the activation of the ERK pathway, and triggered mitochondrial apoptosis in HCC. These findings uncovered a potential therapeutic strategy leveraging the anti-tumor effects of CK against HCC.

Curcumin induces mitochondrial apoptosis in human hepatoma cells through BCLAF1-mediated modulation of PI3K/AKT/GSK-3β signaling

Curcumin is a yellow pigment extracted from the rhizome of turmeric, a traditional Chinese medicine. Here, we tested the hypothesis that curcumin-mediated downregulation of BCLAF1 triggers mitochondrial apoptosis in hepatoma cells by inhibiting PI3K/AKT/GSK-3β signaling. Treatment of the human hepatoma cell lines, HepG2 and SK-Hep-1, with various concentrations of curcumin revealed a time-dependent and concentration-dependent inhibition of cell proliferation, increased apoptosis, cell cycle arrest at the G0/G1 phase, reduced mitochondrial membrane potential, and reduced expression levels of PI3K, p-PI3K, AKT, p-AKT, GSK-3β, and p-GSK-3β. Additionally, curcumin suppressed the levels of apoptotic factors after treating the cells with LY294002, a PI3K inhibitor. Curcumin also suppressed the expression of BCLAF1. Treating stable BCLAF1 knockout HepG2 and SK-Hep-1 cells with curcumin further enhanced apoptosis and increased the number of cells in G0/G1 cell cycle arrest, while inhibiting the downregulation of PI3K/AKT/GSK-3β pathway-related proteins. Treatment of a nude mouse xenograft model bearing HepG2 cells with curcumin inhibited tumor growth, disrupted the cellular structure of the tumor tissue, and suppressed the expression of BCLAF1 and PI3K/AKT/GSK-3β proteins. In summary, our in vitro and in vivo analyses show that curcumin downregulates BCLAF1 expression, inhibits the activation of the PI3K/AKT/GSK-3β pathway, and triggers mitochondrial apoptosis in HCC. These findings uncover a potential therapeutic strategy leveraging the antitumor effects of curcumin against HCC.

Investigation of cell cytotoxic activity and molecular mechanism of 5β,19-epoxycucurbita-6,23(E)-diene-3β,19(R),25-triol isolated from Momordica charantia on hepatoma cells

Context Momordica charantia L. (Cucurbitaceae), known as bitter melon, is an edible fruit cultivated in the tropics. In this study, an active compound, 5β,19-epoxycucurbita-6,23(E)-diene-3β,19(R),25-triol (ECDT), isolated from M. charantia was investigated in regard to its cytotoxic effect on human hepatocellular carcinoma (HCC) cells. Objective To examine the mechanisms of ECDT-induced apoptosis in HCC cells. Materials and methods The inhibitive activity of ECDT on HA22T HCC cells was examined by MTT assay, colony formation assay, wound healing assay, TUNEL/DAPI staining, annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining and JC-1 dye. HA22T cells were treated with ECDT (5, 10, 15, 20 and 25 μM) for 24 h, and the molecular mechanism of cells apoptosis was examined by Western blot. Cells treated with vehicle DMSO were used as the negative control. Results ECDT inhibited the cell proliferation of HA22T cells in a dose-dependent manner. Flow cytometry showed that ECDT treatment at 10–20 μM increased early apoptosis by 10–14% and late apoptosis by 2–5%. Western blot revealed that ECDT treatment activated the mitochondrial-dependent apoptotic pathway, and ECDT-induced apoptosis was mediated by the caspase signalling pathway and activation of JNK and p38MAPK. Pre-treatment of cells with MAPK inhibitors (SB203580 or SP600125) reversed the ECDT-induced cell death, which further supported the involvement of the p38MAPK and JNK pathways. Discussion and conclusions Our results indicated that ECDT can induce apoptosis through the p38MAPK and JNK pathways in HA22T cells. The findings suggested that ECDT has a valuable anticancer property with the potential to be developed as a new chemotherapeutic agent for the treatment of HCC.

Curcumin-loaded zein/pectin nanoparticles: Caco-2 cellular uptake and the effects on cell cycle arrest and apoptosis of human hepatoma cells (HepG2)

Curcumin is a natural plant component with enormous in vitro anticancer effects. However, the bioavailability of curcumin is limited due to its poor solubility in water. Our previous studies showed that zein pectin core/shell nanoparticle-encapsulated curcumin (En-CUR) improved the solubility and bioaccessibility of curcumin. In this study, the transportation mechanism of En-CUR into Caco-2 cells and the inhibitory effects of En-CUR on HepG2 cell proliferation were investigated. The results showed that the uptake of En-CUR by Caco-2 cells required energy consumption. Caveolae-mediated endocytosis, clathrin-dependent endocytosis, and macropinocytosis were involved in the uptake of En-CUR by Caco-2 cells. The apoptosis rate of HepG2 cells after En-CUR treatment was 31.2%, which was approximately two-fold higher than that of the CUR-treated cells treated with curcumin at a concentration of 10 μg/mL, and the early apoptosis rate of En-CUR-treated cells was 2.7–3.3 times higher than that of CUR-treated cells. En-CUR-treated HepG2 cells exhibited more significant cell cycle arrest at cell cycle checkpoints S and G2/M than CUR-treated cells. En-CUR also decreased mitochondrial membrane potential. Western blot analysis revealed that En-CUR increased Bax protein expression, activated caspase-3 and caspase-9, and increased cytochrome c and p53 protein levels in HepG2 cells. Our results suggested that zein-pectin core/shell nanoparticles were desirable curcumin delivery systems and exhibited superior cancer cell antiproliferative effects.

Glutathione-S-transferase activity in various organs of Crocodylus siamensis and its attenuation role in aflatoxin B1-induced cell apoptosis in human hepatocarcinoma cells.

Background and Aim:The crocodile is a model for studying relevant sources of environmental contamination. They were determined an appropriate biomonitoring species for various toxins. The cytosolic and microsomal fraction of crocodiles plays a role in detoxifying xenobiotics. Cytochrome P450 1A2 (CYP1A2) metabolizes aflatoxin B1 (AFB1) to aflatoxin M1, while glutathione-S-transferase (GST) catalyzes carcinogenic agents. This study aimed to investigate the GST activity in various organs of Crocodylus siamensis. Further, the fate of microsomal and cytosolic fractions from various crocodile organs against AFB1-induced apoptosis in human hepatocarcinoma (HepG2) cells was investigated.Materials and Methods:The liver, lungs, intestines, and kidneys tissues from a 3-year-old crocodile (C. siamensis) (n=5) were collected. The cytosolic and microsomal fraction of all tissues was extracted, and protein concentrations were measured with a spectrophotometer. Subsequently, a comparison of GST activity from various organs was carried out by spectrophotometry, and the protective effects of CYP450 and GST activity from various crocodile organs were studied. In vitro AFB1-induced apoptosis in HepG2 cells was detected by reverse transcription-quantitative polymerase chain reaction. Comparisons between the metabolisms of the detoxification enzyme in organs were tested using the Kruskal–Wallis one-way analysis of variance and Dunn’s multiple comparison tests. All kinetic parameters were analyzed using GraphPad Prism software version 5.01 (GraphPad Software Inc., San Diego, USA).Results:Total GST activity in the liver was significantly higher than in the kidneys, intestines, and lungs (p<0.05, respectively). The highest GST pi (GSTP) activity was found in the liver, while the highest GST alpha-isoform activity was in the crocodile lung. The kinetics of total GST and GST mu activity in the liver had the highest velocity compared to other organs. In contrast, the kinetics of GSTP enzyme activity was the highest in the intestine. The in vitro study of microsome and cytosol extract against apoptosis induced by AFB1 revealed that the level of messenger RNA expression of the Bax and Bad genes of HepG2 cells decreased in the treatment group in a combination of cytosolic and microsomal fractions of the crocodile liver but not for Bcl-2. Interestingly, the downregulated expression of Bax and Bad genes was also found in the microsome and cytosol of crocodile kidneys.Conclusion:The crocodile liver revealed very effective GST activity and expression of the highest kinetic velocity compared to other organs. The combination of liver microsomal and cytosolic fractions could be used to prevent cell apoptosis induced by AFB1. However, further study of the molecular approaches to enzyme activity and apoptosis prevention mechanisms should be carried out.

MicroRNA let-7b inhibits hepatitis C virus and induces apoptosis in human hepatoma cells.

Small non-coding RNAs have emerged as essential modulators of viral infections such as hepatitis C virus (HCV). Cellular miRNAs directly regulate the viral infectivity and indirectly by targeting virus-host factors. The current study investigates the inhibitory effect of let-7b miRNA on HCV replication in the Hepatocarcinoma cell line (Huh7.5). The algorithm-based search revealed that let-7b, a high score microRNA, has target sequences on the HCV genome. The Huh7.5 cells were stably transduced with let-7b lentiviral vectors (Huh7.5/let-7b) and mock (Huh7.5/scrambled). The expression of the let-7b level was assessed by real-time PCR assay and Red fluorescence microscope. A dual-luciferase assay was conducted to evaluate the liver-specific let-7b and HCV genome interaction. In the next step, for establishing HCVcc, Full-length HCV-RNA was transduced to naïve Huh7.5, Huh7.5/scrambled, and Huh7.5/let-7b cells. The results of in silico analysis and dual-luciferase reporter assay exhibited a specific interaction of HCV-NS5B and let-7b. Real-time PCR analysis revealed that in contrast to infected naïve Huh7.5 cells and Huh7.5/scrambled, a significant decrease in HCV-RNA load was seen in Huh7.5/let-7b cells. On the other hand, the Flow Cytometry test showed that let-7b could significantly induce the apoptosis pathway in Huh7.5/let-7b. The results also suggest that let-7b, as a target of the HCV genome, potentially reduces HCV replication and raises cell apoptosis rate. We suggest that let-7b directly downregulates HCV replication and may serve as a unique antiviral therapy.

Retraction Note to: Hispidulin induces ER stress-mediated apoptosis in human hepatocellular carcinoma cells in vitro and in vivo by activating AMPK signaling pathway.

Hispidulin (4’,5,7-trihydroxy-6-methoxyflavone) is a phenolic flavonoid isolated from the medicinal plant S. involucrata, which exhibits anti-neoplastic activity against several types of cancer. However, the mechanism underlying its anti-cancer activity against hepatocellular carcinoma (HCC) has not been fully elucidated. In this study, we investigated whether and how hispidulin-induced apoptosis of human HCC cells in vitro and in vivo. We showed that hispidulin (10, 20 μmol/L) dose-dependently inhibited cell growth and promoted apoptosis through mitochondrial apoptosis pathway in human HCC SMMC7721 cells and Huh7 cells. More importantly, we revealed that its pro-apoptotic effects depended on endoplasmic reticulum stress (ERS) and unfolded protein response (UPR), as pretreatment with salubrinal, a selective ERS inhibitor, or shRNA targeting a UPR protein CHOP effectively abrogated hispidulin-induced cell apoptosis. Furthermore, we showed that hispidulin-induced apoptosis was mediated by activation of AMPK/mTOR signaling pathway as pretreatment with Compound C, an AMPK inhibitor, or AMPK-targeting siRNA reversed the pro-apoptotic effect of hispidulin. In HCC xenograft nude mice, administration of hispidulin (25, 50 mg/kg every day, ip, for 27 days) dose-dependently suppressed the tumor growth, accompanied by inducing ERS and apoptosis in tumor tissue. Taken together, our results demonstrate that hispidulin induces ERS-mediated apoptosis in HCC cells via activating the AMPK/mTOR pathway. This study provides new insights into the anti-tumor activity of hispidulin in HCC.

Phosphodiesterase 4D Depletion/Inhibition Exerts Anti-Oncogenic Properties in Hepatocellular Carcinoma.

Simple SummaryHepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide. Drug resistance is a serious problem in the treatment of HCC. Therefore, it is of high clinical impact to discover targeted therapies that may overcome drug-related resistance and improve the survival of patients affected by HCC. In the present study, we investigated the role of Isoform D of type 4 phosphodiesterase (PDE4D) in HCC development and progression. We found that PDE4D is over-expressed HCCs in vitro and in vivo and the depletion of the gene by silencing or the pharmacological inhibition of protein activity exerted anti-tumorigenic activities.Isoform D of type 4 phosphodiesterase (PDE4D) has recently been associated with several human cancer types with the exception of human hepatocellular carcinoma (HCC). Here we explored the role of PDE4D in HCC. We found that PDE4D gene/protein were over-expressed in different samples of human HCCs compared to normal livers. Accordingly, HCC cells showed higher PDE4D activity than non-tumorigenic cells, accompanied by over-expression of the PDE4D isoform. Silencing of PDE4D gene and pharmacological inhibition of protein activity by the specific inhibitor Gebr-7b reduced cell proliferation and increased apoptosis in HCC cells, with a decreased fraction of cells in S phase and a differential modulation of key regulators of cell cycle and apoptosis. PDE4D silencing/inhibition also affected the gene expression of several cancer-related genes, such as the pro-oncogenic insulin growth factor (IGF2), which is down-regulated. Finally, gene expression data, available in the CancerLivER data base, confirm that PDE4D over-expression in human HCCs correlated with an increased expression of IGF2, suggesting a new possible molecular network that requires further investigations. In conclusion, intracellular depletion/inhibition of PDE4D prevents the growth of HCC cells, displaying anti-oncogenic effects. PDE4D may thus represent a new biomarker for diagnosis and a potential adjuvant target for HCC therapy.

Atractylenolide III predisposes miR-195-5p/FGFR1 signaling axis to exert tumor-suppressive functions in liver cancer.

Antineoplastic activity of atractylenolide III (ATL) has been reported in several malignant tumors. However, its activity has not been completely clarified in hepatocellular carcinoma (HCC). Herein, anticancer effects and underlying molecular mechanisms of ATL were investigated in HCC cells in vitro. Cell viability was evaluated by CCK-8 assay. Cell migration and invasion were evaluated using the transwell assay. TUNEL staining was performed to evaluate cell apoptosis. Protein expression was measured by western blotting analysis. Online database TargetScan and luciferase reporter gene analysis were performed to validate FGFR1 as a target of miR-195-5p. HepG2 and SMMC7721 cell growth, migration, and invasion were inhibited by ATL treatment in a dose-dependent pattern. ATL treatment-induced apoptosis of HepG2 and SMMC7721 cells. Intriguingly, ATL treatment unexpectedly inhibited FGFR1 protein expression in HepG2 and SMMC7721 cells. Knockdown of FGFR1 inhibited proliferation, migration, and invasion, and evoked apoptosis of HepG2 and SMMC7721 cells. We also found that ATL treatment could increase the expression of miR-195-5p, which as a posttranscriptional targeted FGFR1. In HCC tissues, miR-195-5p expression is negatively correlated with FGFR1. Furthermore, the antiproliferative and proapoptotic roles of miR-195-5p were neutralized by overexpressed FGFR1 in HCC cells. ATL effectively repressed growth and induced apoptosis of human HCC cells through the upregulation of miR-195-5p to downregulate FGFR1 expression. Atractylenolide III as a bioactive anticancer adjuvant medication will provide chemosensitization strategy for reversing the drug resistance of HCC.

Bioinformatic analysis of RHO family of GTPases identifies RAC1 pharmacological inhibition as a new therapeutic strategy for hepatocellular carcinoma

ObjectiveThe RHO family of GTPases, particularly RAC1, has been linked with hepatocarcinogenesis, suggesting that their inhibition might be a rational therapeutic approach. We aimed to identify and target deregulated RHO...

CHD4/NuRD complex regulates complement gene expression and correlates with CD8 T cell infiltration in human hepatocellular carcinoma

BackgroundsThe NuRD (Nucleosome Remodeling and Deacetylation) complex is a repressive complex in gene transcription by modulating chromatin accessibility of target genes to transcription factors and RNA polymerase II. Although individual subunits of the complex have been implicated in many other cancer types, the complex’s role in human hepatocellular carcinoma (HCC) is not fully understood. More importantly, the NuRD complex has not yet been investigated as a whole in cancers.MethodsWe analyzed the expression of the NuRD complex in HCC and evaluated the prognostic value of NuRD complex expression in HCC using the RNA-seq data obtained from the TCGA project. We examined the effect of CHD4 knockdown on HCC cell proliferation, apoptosis, migration, invasion, epithelial-mesenchymal transition, colony-forming ability, and on complement gene expression. We also performed bioinformatic analyses to investigate the correlation between the NuRD complex expression and immune infiltration.ResultsWe found that nine subunits, out of 14 subunits of the NuRD complex examined, were significantly overexpressed in HCC, and their expression levels were positively correlated with cancer progression. More importantly, our data also demonstrated that these subunits tended to be overexpressed as a whole in HCC. Subsequent studies demonstrated that knockdown of CHD4 in HCC cells inhibits cell proliferation, migration, invasion, and colony-forming ability and promotes apoptosis of HCC cells, indicating that the CHD4/NuRD complex plays oncogenic roles in HCC. Further analysis revealed that the CHD4/NuRD complex regulates complement gene expression in HCC. Intriguingly, we found that the CHD4/NuRD complex expression was inversely correlated with CD8 T cell infiltration in HCC.ConclusionsOur data demonstrate that the CHD4/NuRD complex plays an oncogenic role in human HCC and regulates complement gene expression in HCC cells. The results of inverse correlation between the CHD4/NuRD complex and CD8 T cell and DC cell infiltration in HCC suggest that the CHD4/NuRD complex not only plays direct regulatory roles in HCC cells, but also has an impact on the immune microenvironment of HCC.

Cryptotanshinone Induces Apoptosis and Inhibits Migration and Invasion in Human Hepatocellular Carcinoma Cells In Vitro

Cryptotanshinone (CPT), an active quinoid diterpene isolated from Salvia miltiorrhiza Bunge, was previously reported to have potential anticancer effects. However, the mechanisms of CPT on hepatocellular carcinoma (HCC) cells are not well understood. In this study, we investigated the anticancer effects of CPT on HCC cells. Thiazolyl blue tetrazolium bromide assay showed dose-dependent and time-dependent cytotoxicity of CPT on human HCC cells, especially in HCCLM3 and Huh-7 cells. Hoechst 33258 stain, flow cytometry assay, and Western blot assay all indicated that CPT could distinctly induce the apoptosis of human HCC cells and break intracellular homeostasis by triggering the imbalance of mitochondrial transmembrane potential ( Δψm) and reactive oxygen species. In addition, CPT could significantly inhibit HCCLM3 and Huh-7 cells’ migration and invasion via the signal transducers and activators of transcription 3/matrix metalloproteinases mediated signaling pathway. Our findings demonstrated that the antitumor effects of CPT on human HCC cells were by suppressing cell proliferation, inducing cell apoptosis and impairing cell migration and invasion.