Genetic switch selectively kills hepatocellular carcinoma cell based on microRNA and tissue-specific promoter.

The clinical treatment of hepatocellular carcinoma (HCC) is still a heavy burden worldwide. Intracellular microRNAs (miRNAs) commonly express abnormally in cancers, thus they are potential therapeutic targets for cancer treatment. miR-21 is upregulated in HCC whereas miR-122 is enriched in normal hepatocyte but downregulated in HCC. In our study, we first generated a reporter genetic switch compromising of miR-21 and miR-122 sponges as sensor, green fluorescent protein (GFP) as reporter gene and L7Ae:K-turn as regulatory element. The reporter expression was turned up in miR-21 enriched environment while turned down in miR-122 enriched environment, indicating that the reporter switch is able to respond distinctly to different miRNA environment. Furthermore, an AAT promoter, which is hepatocyte-specific, is applied to increase the specificity to hepatocyte. A killing switch with AAT promoter and an apoptosis-inducing element, Bax, in addition to miR-21 and miR-122 significantly inhibited cell viability in Huh-7 by 70 % and in HepG2 by 60 %. By contrast, cell viability was not affected in five non-HCC cells. Thus, we provide a novel feasible strategy to improve the safety of miRNA-based therapeutic agent to cancer.

Discovery of Dolutegravir Derivative against Liver Cancer via Inducing Autophagy and DNA Damage.

We introduced a terminal alkyne into the core structure of dolutegravir, resulting in the synthesis of 34 novel dolutegravir-1,2,3-triazole compounds through click chemistry. These compounds exhibited remarkable inhibitory activities against two hepatocellular carcinoma cell lines, Huh7 and HepG2. Notably, compounds 5e and 5p demonstrated exceptional efficacy, particularly against Huh7 cells, with IC50 values of 2.64 and 5.42 µM. Additionally, both compounds induced apoptosis in Huh7 cells, suppressed tumor cell clone formation, and elevated reactive oxygen species (ROS) levels, further promoting tumor cell apoptosis. Furthermore, compounds 5e and 5p activated the LC3 signaling pathway, inducing autophagy, and triggered the γ-H2AX signaling pathway, resulting in DNA damage in tumor cells. Compound 5e exhibited low toxicity, highlighting its potential as a promising anti-tumor drug.

Identification and evaluation of an appropriate housekeeping gene for real time gene profiling of hepatocellular carcinoma cells cultured in three dimensional scaffold.

BACKGROUND: Assessing an optimal reference gene as an internal control for target gene normalization is important during quantitative real time polymerase chain reaction (RT-qPCR) of three dimensional (3D) cell culture. Especially, gene profiling of cancer cells under a complex 3D microenvironment in a polymer scaffold provides a deeper understanding of tumor functioning in vivo. METHODS AND RESULTS: Expression of six housekeeping genes (HKG's): Glyceraldehyde-3-phosphodehydrogenase (GAPDH), ß-actin (ACTB), beta-2-microglobulin (B2M), 18S ribosomal RNA (18S rRNA), peptidyl-propyl-isomerase A (PPIA), and ribosomal protein L13 (RPL-13) during two dimensional (2D) culture, and alginate-carboxymethylcellulose scaffold based 3D culture conditioned up to 21 days was analysed for hepatocellular carcinoma (Huh-7) cells. The gene expression studies were performed by determining primer efficiency, melting curve and threshold cycle analysis. Further, RT-qPCR data was validated statistically using geNorm and NormFinder softwares. The study indicated RPL-13, 18S rRNA and B2M to be stable among selected referral HKG candidates. CONCLUSION: An exploration of a reliable HKG is necessary for normalization of gene expression in RT-qPCR during varying cell culture conditions.

Fenbendazole Suppresses Growth and Induces Apoptosis of Actively Growing H4IIE Hepatocellular Carcinoma Cells via p21-Mediated Cell-Cycle Arrest.

Bendimidazole anthelmintics (BAs) have gained interest for their anticancer activity. The anticancer activity is mediated via multiple intracellular changes, which are not consistent under different conditions even in the same cells. We investigated the anticancer activity of fenbendazole (FZ, one of BAs) under two different growth conditions. The growth rate of H4IIE cells was dose-dependently decreased by FZ only in actively growing cells but not in fully confluent quiescent cells. Apoptosis-associated changes were also induced by FZ in actively growing cells. Markers of autophagy were not changed by FZ. The number of cells was markedly increased in sub-G1 phase but decreased in S- and G2/M phases by FZ. FZ up-regulated p21 (an inhibitor of cyclin-CDK) but suppressed the expression of cell cycle-promoting proteins (cyclin D1 and cyclin B1). FZ did not affect integrin αV or n-cadherin expression as well as cell migration. Glycolytic changes (glucose consumption and lactate production) and the generation of reactive oxygen species (ROS) were not affected by FZ. Although the activity of mitogen-activated protein kinases (MAPKs) was altered by FZ, the inhibition of MAPKs did not affect the pro-apoptotic activity of FZ. Taken together, FZ selectively suppressed the growth of cells via p21-mediated cell cycle arrest at G1/S and G2/M, and resulted in apoptosis only in actively growing cells but not in quiescent cells. Glucose metabolism, ROS generation, and MAPKs are unlikely targets of FZ at least in H4IIE rat hepatocellular carcinoma cells used in this study.

Selective Anti-Cancer Effects of Plasma-Activated Medium and Its High Efficacy with Cisplatin on Hepatocellular Carcinoma with Cancer Stem Cell Characteristics.

Hepatocellular carcinoma (HCC) is a major histological subtype of primary liver cancer. Ample evidence suggests that the pathological properties of HCC originate from hepatic cancer stem cells (CSCs), which are responsible for carcinogenesis, recurrence, and drug resistance. Cold atmospheric-pressure plasma (CAP) and plasma-activated medium (PAM) induce apoptosis in cancer cells and represent novel and powerful anti-cancer agents. This study aimed to determine the anti-cancer effect of CAP and PAM in HCC cell lines with CSC characteristics. We showed that the air-based CAP and PAM selectively induced cell death in Hep3B and Huh7 cells with CSC characteristics, but not in the normal liver cell line, MIHA. We observed both caspase-dependent and -independent cell death in the PAM-treated HCC cell lines. Moreover, we determined whether combinatorial PAM therapy with various anti-cancer agents have an additive effect on cell death in Huh7. We found that PAM highly increased the efficacy of the chemotherapeutic agent, cisplatin, while enhanced the anti-cancer effect of doxorubicin and the targeted-therapy drugs, trametinib and sorafenib to a lesser extent. These findings support the application of CAP and PAM as anti-cancer agents to induce selective cell death in cancers containing CSCs, suggesting that the combinatorial use of PAM and some specific anti-cancer agents is complemented mechanistically.

Cold Atmospheric Pressure Plasma-Activated Medium Induces Selective Cell Death in Human Hepatocellular Carcinoma Cells Independently of Singlet Oxygen, Hydrogen Peroxide, Nitric Oxide and Nitrite/Nitrate.

Cold atmospheric pressure plasma (CAP) and plasma-activated medium (PAM) induce cell death in diverse cancer cells and may function as powerful anti-cancer agents. The main components responsible for the selective anti-cancer effects of CAP and PAM remain elusive. CAP or PAM induces selective cell death in hepatocellular carcinoma cell lines Hep3B and Huh7 containing populations with cancer stem cell markers. Here, we investigated the major component(s) of CAP and PAM for mediating the selective anti-proliferative effect on Hep3B and Huh7 cells. The anti-proliferative effect of CAP was mediated through the medium; however, the reactive oxygen species scavenger N-acetyl cysteine did not suppress PAM-induced cell death. Neither high concentrations of nitrite or nitrite/nitrate nor a low concentration of H2O2 present in the PAM containing sodium pyruvate affected the viability of Hep3B and Huh7 cells. Inhibitors of singlet oxygen, superoxide anions, and nitric oxide retained the capacity of PAM to induce anti-cancer effects. The anti-cancer effect was largely blocked in the PAM prepared by placing an aluminum metal mesh, but not a dielectric PVC mesh, between the plasma source and the medium. Hence, singlet oxygen, hydrogen peroxide, nitric oxide, and nitrite/nitrate are not the main factors responsible for PAM-mediated selective death in Hep3B and Huh7 cells. Other factors, such as charged particles including various ions in CAP and PAM, may induce selective anti-cancer effects in certain cancer cells.

Three-Dimensional Aggregated Spheroid Model of Hepatocellular Carcinoma Using a 96-Pillar/Well Plate.

A common method of three-dimensional (3D) cell cultures is embedding single cells in Matrigel. Separated cells in Matrigel migrate or grow to form spheroids but lack cell-to-cell interaction, which causes difficulty or delay in forming mature spheroids. To address this issue, we proposed a 3D aggregated spheroid model (ASM) to create large single spheroids by aggregating cells in Matrigel attached to the surface of 96-pillar plates. Before gelling the Matrigel, we placed the pillar inserts into blank wells where gravity allowed the cells to gather at the curved end. In a drug screening assay, the ASM with Hepatocellular carcinoma (HCC) cell lines showed higher drug resistance compared to both a conventional spheroid model (CSM) and a two-dimensional (2D) cell culture model. With protein expression, cytokine activation, and penetration analysis, the ASM showed higher expression of cancer markers associated with proliferation (p-AKT, p-Erk), tight junction formation (Fibronectin, ZO-1, Occludin), and epithelial cell identity (E-cadherin) in HCC cells. Furthermore, cytokine factors were increased, which were associated with immune cell recruitment/activation (MIF-3α), extracellular matrix regulation (TIMP-2), cancer interaction (IL-8, TGF-ß2), and angiogenesis regulation (VEGF-A). Compared to CSM, the ASM also showed limited drug penetration in doxorubicin, which appears in tissues in vivo. Thus, the proposed ASM better recapitulated the tumor microenvironment and can provide for more instructive data during in vitro drug screening assays of tumor cells and improved prediction of efficacious drugs in HCC patients.

LncRNA ST8SIA6-AS1 promotes hepatocellular carcinoma cell proliferation and resistance to apoptosis by targeting miR-4656/HDAC11 axis.

BACKGROUND: Dysregulation of long non-coding RNAs (lncRNAs) results in development of human diseases including hepatocellular carcinoma (HCC). Although several HCC related lncRNAs have been reported, the biological functions of many lncRNAs during the development of HCC remains unknown. METHODS: The expression of ST8SIA6-AS1 was studied by realtime PCR (RT-qPCR) and bioinformatic analysis. The biological functions of ST8SIA6-AS1 was examined by CCK-8 assay and flow cytometry analysis. The target of ST8SIA6-AS1 was analyzed by bioinformatic analysis and validated by dual luciferase reporter assay, western blotting and RT-qPCR. RESULTS: In this study we demonstrated that ST8SIA6-AS1 was an upregulated lncRNA in hepatocellular carcinoma. SiRNA-mediated knockdown of ST8SIA6-AS1 repressed cell proliferation and induced cell apoptosis in HCC cells. Bioinformatic analysis and RT-qPCR further showed that ST8SIA6-AS1 mainly located in cytoplasm. Dual luciferase reporter assay further revealed that ST8SIA6-AS1 interacted with miR-4656 in HCC cells. In addition, HDAC11 was identified as a target gene in HCC cells and ST8SIA6-AS1 could upregulate HDAC11 via sponging miR-4656. Transfection of recombinant HDAC11 partially rescued the inhibition of cell proliferation and increase of cell apoptosis inducing by knockdown of ST8SIA6-AS1. CONCLUSION: In conclusion, our findings suggested that ST8SIA6-AS1 was a novel upregulated lncRNA in HCC and could facilitate cell proliferation and resistance to cell apoptosis via sponging miR-4656 and elevation of HDAC11, which might be a promising biomarker for patients with HCC.

HSP4 triggers epithelial-mesenchymal transition and promotes motility capacities of hepatocellular carcinoma cells via activating AKT.

BACKGROUND AND AIMS: Heat shock factor (HSF4) plays a vital role in carcinogenesis and tumour progression. However, its clinical significance implications in hepatocellular carcinoma (HCC) remained elusive. METHODS: RT-PCR and western blot were used to detect the HSF4 expression levels in HCC cells and tissues. Immunohistochemistry staining was performed on a tissue microarray containing 104 HCC patients received radical resection. In vitro effects of HSF4 on proliferation, migration and invasion were determined by colony formation and transwell assays in HCCLM3, Huh7, MHCC97L and SMMC7721 cells. Epithelial-mesenchymal transition (EMT) was identified by RT-PCR, WB and immunofluorescence in HCCLM3 and MHCC97L cells. AKT pathway activation was detected by WB and dual luciferase report system in HCCLM3 and MHCC97L cells. RESULTS: HSF4 expression was higher in primary HCC tissues derived from recurrent patients, and positively correlated with invasiveness potentials of cell lines. Clinically, patients with high HSF4 expression had significant poorer prognosis. In vitro experiments showed HSF4 silencing inhibited HCC cell proliferation, migration and invasion, whereas HSF4 overexpression had inverse effects. Moreover, silence of HSF4 induced an epithelial-like phenotype, whereas the overexpression of HSF4 resulted in a mesenchymal-like phenotype in HCC by activating AKT pathway. Further experiments showed that HSF4 could activate AKT pathway in a hypoxia-inducible factor-1α (HIF-1α) dependent, but transforming growth factor-ß (TGF-ß) independent manner. CONCLUSIONS: HSF4 is upregulated in HCC, resulting in greater proliferation, migration and invasion capacities. Moreover, high HSF4 expression is a promising predictive indicator of poor outcome after radical resection. HSF4 may promote aggressive tumour behaviour by enhancing EMT through activating AKT pathway in a HIF1α-dependent manner.

Assessment of the microbial contamination of mechanical protection gloves used on waste sorting industry: A contribution for the risk characterization.

In Portugal, mechanical protection gloves (MPG) are of mandatory use and during their use sweat is released and, consequently, the humidity of the material increases leading to conditions favorable to the growth of microorganisms. However, no studies have been conducted in MPG to assess the bioburden. This study intended to determine the bioburden present in MPG and their biological effects, and to discuss the possibility to use MPG as a passive method to assess occupational exposure to microbial contamination. Fungal burden was characterized through molecular tools for fungal toxigenic species, and antifungal resistance and mycotoxins profiles were determined. Cell viability was determined in swine kidney (SK) monolayer and hepatocellular carcinoma (Hep G2) cell lines. All MPG samples presented Gram-negative bacteria. The fungal contamination ranged from 0 CFU.m-2 in both MEA and DG18, to 5.09 × 106 and 2.75 × 106 and the most commonly fungi found was Aspergillus spp. (50.46%). Azole resistant Aspergillus sections were found in azole supplemented media. Aspergillus sections (Circumdati, Flavi, Fumigati and Versicolores) were detected by molecular tools in 66 out of 67 samples. The most reported mycotoxin was mycophenolic acid (89.6%). HepG2 cells appear to be more sensitive to MPG contamination, with high cytotoxicity (IC50 < 0.05 mm2/ml) observed for 18 out of 57 gloves. MPG can be used in passive sampling to assess occupational exposure to bioburden in waste sorting industries and contribute for risk characterization. Some contaminants of MPG had cytotoxic potential and affected the biology of hepatic cells more than renal cells.

Y-Box Binding Protein-1 Promotes Epithelial-Mesenchymal Transition in Sorafenib-Resistant Hepatocellular Carcinoma Cells.

Hepatocellular carcinoma is one of the most common cancer types worldwide. In cases of advanced-stage disease, sorafenib is considered the treatment of choice. However, resistance to sorafenib remains a major obstacle for effective clinical application. Based on integrated phosphoproteomic and The Cancer Genome Atlas (TCGA) data, we identified a transcription factor, Y-box binding protein-1 (YB-1), with elevated phosphorylation of Ser102 in sorafenib-resistant HuH-7R cells. Phosphoinositide-3-kinase (PI3K) and protein kinase B (AKT) were activated by sorafenib, which, in turn, increased the phosphorylation level of YB-1. In functional analyses, knockdown of YB-1 led to decreased cell migration and invasion in vitro. At the molecular level, inhibition of YB-1 induced suppression of zinc-finger protein SNAI1 (Snail), twist-related protein 1 (Twist1), zinc-finger E-box-binding homeobox 1 (Zeb1), matrix metalloproteinase-2 (MMP-2) and vimentin levels, implying a role of YB-1 in the epithelial-mesenchymal transition (EMT) process in HuH-7R cells. Additionally, YB-1 contributes to morphological alterations resulting from F-actin rearrangement through Cdc42 activation. Mutation analyses revealed that phosphorylation at S102 affects the migratory and invasive potential of HuH-7R cells. Our collective findings suggest that sorafenib promotes YB-1 phosphorylation through effect from the EGFR/PI3K/AKT pathway, leading to significant enhancement of hepatocellular carcinoma (HCC) cell metastasis. Elucidation of the specific mechanisms of action of YB-1 may aid in the development of effective strategies to suppress metastasis and overcome resistance.

LncRNA CRNDE promotes hepatocellular carcinoma cell proliferation, invasion, and migration through regulating miR-203/ BCAT1 axis.

OBJECTIVE: To investigate the impact of long noncodingRNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) on hepatocellular cancer (HCC) cell propagation, invasion, and migration by mediating miR-203/ BCAT1 axis. METHODS: Microarray analysis was based on 25 pairs of HCC cancerous tissues and adjacent tissues. The expression levels of CRNDE, miR-203, and BCAT1 in HCC tissues were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The liver cell line L-02 and HCC cell lines HepG2 and Huh-7 were utilized to assess the regulatory effects of CRNDE and miR-203 on HCC progression in vitro. Western blot was used to qualify BCAT1 protein expression level. Cell proliferation and apoptosis were evaluated using CCK-8 and flow cytometry analysis, whereas cell invasion and migration assay were performed by the Transwell assay. The relationship among CRNDE, miR-203, and BCAT1 was validated by dual luciferase assay. Tumor Xenograft study was established to verify the pathological effect of CRNDE on HCC development in vivo. RESULTS: The expression levels of the CRNDE and BCAT1 were upregulated in HCC tissues and cells, whereas miR-203 was downregulated in HCC. Knockdown of CRNDE or miR-203 overexpression would inhibit HCC cell propagation and metastasis, and induced cell apoptosis. Moreover, miR-203 was negatively correlated with CRNDE, the same as miR-203 with BCAT1. Dual luciferase assay showed that miR-203 was an inhibitory target of CRNDE, and BCAT1 was directly targeted by miR-203 as well. CONCLUSION: LncRNA CRNDE could enhance HCC tumorgenesis by sponging miR-203 and mediating BCAT1. LncRNA CRNDE might facilitate HCC cell propagation, invasiveness, and migration through regulating miR-203/ BCAT1 axis.

Metformin Induces Oxidative Stress-Mediated Apoptosis without the Blockade of Glycolysis in H4IIE Hepatocellular Carcinoma Cells.

Metformin, a widely prescribed anti-diabetic drug, also exerts anti-cancer effects in different types of cancers. Although a number of molecular mechanisms have been suggested, the metabolic features underlying metformin's anti-cancer activity is not fully understood enough. Because cancer cells have been known to prefer inefficient aerobic glycolysis to support their proliferation, it is important to clarify by which metformin affects metabolism to suppress the proliferation of cancer cells. Here, we report the metabolic changes induced by metformin and its relevance to the induction of apoptosis in H4II rat hepatocellular carcinoma cells. H4IIE cells were treated with metformin and other reagents in culture media with various nutritional compositions. Glutamine as well as pyruvate enhanced the viability of H4IIE cells in glucose-deprived conditions. Protective effects of glucose and pyruvate were comparable at same concentrations (5 mM). Metformin induced apoptosis irrespective of any nutritional conditions. Glucose consumption and lactate production were stimulated by metformin. Inhibition of glycolysis by 2-deoxyglucose suppressed the metformin-induced lactate production but additively enhanced metformin's pro-apoptotic effect. These results indicate that metformin does not interfere but accelerate glycolysis. Unexpectedly, the production of reactive oxygen species (ROS) was markedly stimulated by metformin. A potent antioxidant, N-acetylcysteine (NAC) suppressed all pro-apoptotic changes as well as ROS generation induced by metformin. Taken together, metformin does not interfere with glycolysis but promotes apoptosis by enhancing oxidative stress.

Synergistic antimetastatic effect of cotreatment with licochalcone A and sorafenib on human hepatocellular carcinoma cells through the inactivation of MKK4/JNK and uPA expression.

To improve the clinical outcome of tumor chemotherapy, more effective combination treatments against tumor metastasis and recurrence are required. Licochalcone A (LicA) is the root of Glycyrrhiza inflata and has been reported to possess anti-inflammatory, antimicrobial, and antitumor effects. Sorafenib (Sor), a multikinase inhibitor, is used to treat patients with solid tumors such as advanced hepatocellular carcinoma (HCC). However, the synergistic effects of LicA and Sor on the metastasis of human HCC cells have not been reported. We found that LicA and Sor did not have cytotoxic effects or arrest growth in human SK-Hep-1 and Huh-7 cells. In addition, treatment with LicA or Sor alone inhibited migration and invasion in human SK-Hep-1 and Huh-7 HCC cells. Furthermore, cotreatment with LicA and Sor synergistically inhibited the migration and invasion of HCC cells and significantly inhibited uPA protein expression. Notably, cotreatment of LicA and Sor synergistically and significantly downregulated MKK4-JNK expression. Through tail vein injection in nude mice, the aforementioned cotreatment synergistically suppressed SK-Hep-1 cell-mediated lung metastasis. These findings first revealed the synergistic effects of LicA and Sor cotreatment against human HCC cells, further suggesting that beneficial effects on tumor regression could be confirmed through prospective clinical trials.

E167K polymorphism of TM6SF2 gene affects cell cycle of hepatocellular carcinoma cell HEPA 1-6.

BACKGROUND: Some studties reported that the polymorphism of TM6SF2 gene E167K affects the occurrence and the progression of hepatocytes carcinoma (hepatocellular, HCC). In oeder to investigate the effects of the polymorphism of TM6SF2 gene E167K in the pathogenesis of HCC, we explored its influence on the cell cycle in hepatocellular carcinoma cell HEPA1-6. METHODS: HEPA 1-6 cells which could respectively overexpress TM6SF2 wild type and E167K variant were cultured and HEPA 1-6 cells with zero load plasmids were used as matched control. Flow cytometry was used to detect the cell cycles of these 3 type of HEPA 1-6 cells. Realtime fluores-cence quantitative PCR and western blot were used to analyzed the expression of regulatory factors (Cyclin D1、p53、P16、P27、P21 and Rb) of cell cycle. T-test was used in statistical analysis. RESULTS: Cell cycle phase distribution was presented by the proportion of cells in each phases (%). Compared with the control group, the cell cycle phase distribution (G1 phase 57.36 ± 0.21%, G2/M phase 25.61 ± 0.36%,S phases 19.31 ± 0.25%) had no differences in wild type group (G1 phase 57.63 ± 0.28%, G2/M phase 25.77 ± 0.51%, S phases 19.54 ± 0.25%; P < 0.05). Between variant type group and wild type group,G1 phase was significantly decreased (variant type group G1 phase 36.26 ± 0.31%, P < 0.05),S phase and G2/M phase were increased(variant type group S phase 28.41 ± 0.31%, P < 0.05;G2/M phase 35.23 ± 0.14%, P < 0.05), respectively. Compared with control group,the relative expression of CyclinD1、P53 and Rb mRNA in variant type group was significantly upregulated (2.03 ± 0.01 VS 1.04 ± 0.06, 1.88 ± 0.05 VS 1.37 ± 0.03, 1.29 ± 0.06 VS 1.15 ± 0.03, P < 0.05) and P27 mRNA in variant type group was significantly downregulated (0.56 ± 0.02 VS 0.85 ± 0.05, P < 0.05). Compared with wild type group, the relative expression of CyclinD1、P53 and Rb mRNA in variant type group was significantly upregulated (wild type group 1.00 ± 0.00, 1.48 ± 0.09, 1.18 ± 0.01, P < 0.05) and P27 mRNA in variant type group was significantly downregulated (variant type group 0.82 ± 0.05,P < 0.05). There was no statistical significance between wild type group and control group (P > 0.05). P16 and P21 expression showed no statistical sigtfificance in any of these three groups (P > 0.05). CONCLUSION: E167K polymorphism of TM6SF2 gene affects cell cycles of HEPA1-6 cells via up-regulating CyclinD1、P53 and Rb and down-regulating P27.

ß-mangostin suppresses human hepatocellular carcinoma cell invasion through inhibition of MMP-2 and MMP-9 expression and activating the ERK and JNK pathways.

ß-mangostin is a dietary xanthone that has been reported to have the anticancer properties in some human cancer cell types. However, the antimetastatic effect and molecular mechanism of ß-mangostin action in human hepatocellular carcinoma (HCC) cells remain unknown. In this study, we found that ß-mangostin did not induce cytotoxicity in human HCC cells (SK-Hep-1, Huh-7 and HA22T/VGH cells). ß-mangostin could inhibit migration and invasion of human HCC cells. Meanwhile, ß-mangostin significantly decreased the protein activities and expression of matrix metalloproteinase (MMP)-2 and MMP-9 via increasing the activation of MEK1/2, ERK1/2, MEK4 and JNK1/2 signaling pathways. Furthermore, using specific inhibitor for ERK1/2 (PD98059) and JNK1/2 (JNKII) significantly restored the expression of MMP-2/-9 and invasion by ß-mangostin treatment in Huh-7 cells. In addition, ß-mangostin effectively restored the protein levels and transcription activity of MMP-2 and MMP-9 in siERK or siJNK-transfected Huh-7 cells, concomitantly with promotion on cell migration and invasion. Taken together, these findings are the first to demonstrate the antimetastatic activity of ß-mangostin against human HCC cells, which may act as a promising therapeutic agent for the treatment of HCC.

[Hepatitis B core antigen promotes invasion of hepatocellular carcinoma cell line HepG2.2.15 via Toll-like receptor 4].

Objective: To investigate the effect of hepatitis B core antigen (HBcAg) in promoting the invasion of hepatitis B virus (HBV)-related hepatocellular carcinoma cell line HepG2.2.15 and the role of Toll-like receptor 4 (TLR4) in the mechanism. Methods: TLR4 mRNA and protein expression in HepG2 cells and HepG2.2.15 cells was measured by reverse transcription real-time PCR and Western blot analysis, respectively. HepG2.2.15 cells were transfected with TLR4 specific small interfering RNA (siRNA) to silence TLR4 expression, and stimulated by recombinant HBcAg in culture. The invasion of cells was measured by Transwell invasion assay. The expression of TLR4 signaling pathway-related proteins in the cultured cells and proinflammatory cytokines in the supernatant was also determined. The student's t-test, one-way ANOVA, and SNK-q test were used for statistical analysis. Results: TLR4 mRNA and protein expression in HepG2.2.15 cells was significantly higher than that in HepG2 cells. TLR4 siRNA transfection remarkably down-regulated TLR4 expression in HepG2.2.15 cells. Inhibiting TLR4 expression and/or HBcAg stimulation did not affect the proliferation of HepG2.2.15 cells. However, HBcAg stimulation significantly increased the invasion ability of HepG2.2.15 cells and the secretion of proinflammatory cytokines [including interferon (IFN)-γ, interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α]. Inhibiting TLR4 expression significantly reduced HBcAg-induced cellular invasion. Meanwhile, HBcAg stimulation elevated the expression of MyD88 and TRIF in HepG2.2.15 cells. TLR4 silencing inhibited HBcAg-induced increase in the expression of MyD88, while it showed no significant impact on TRIF expression. Conclusion: HBcAg can promote the invasion of HepG2.2.15 cells. The TLR4/MyD88 signaling pathway may be involved in this process by inducing the expression of proinflammatory cytokines.

Poly (ADP-ribose) polymerase inhibition synergizes with the NF-κB inhibitor DHMEQ to kill hepatocellular carcinoma cells.

UNLABELLED: Poly (ADP-ribose) polymerase (PARP) enzymes play a key role in the cellular machinery responsible for DNA repair. Dehydroxymethylepoxyquinomicin (DHMEQ), a new inhibitor of NF-κB, induces oxidative stress and DNA damage. The effects of DHMEQ in combination with Olaparib (PARP inhibitor) were studied on hepatocellular carcinoma (HCC) cells. The DHMEQ-Olaparib combination synergistically inhibited cell viability, cell proliferation and colony formation of Hep3B, but had additive effects on Huh7 cells. The synergistic effects of the combination correlated with increased apoptosis, caspase 3/7 activity and PARP cleavage. There was an induction of an endoplasmic reticulum (ER) stress response with significant up-regulation of CHOP and TRB3 genes and splicing of XBP1 mRNA in Hep3B cells but not in Huh7 cells. Silencing of the TRB3 mRNA in Hep3B cells reversed the reduction in viability caused by DHMEQ-Olaparib treatment, while depletion of unspliced XBP1 mRNA in DHMEQ-Olaparib-treated Huh7 cells reduced viability. ROS production was increased after DHMEQ-Olaparib treatment of Hep3B, which caused DNA damage by an accumulation of γH2AX, increased AKT phosphorylation and reduced cell viability. The combination reduced Rad51 nuclear foci in Hep3B cells (not Huh7 cells), and silencing of Rad51 enhanced sensitivity of Huh7 cells to the DHMEQ-Olaparib combination. Knockdown of AKT in Hep3B cells restored the number of Rad51 nuclear foci after DHMEQ-Olaparib treatment. In summary, the DHMEQ-Olaparib combination induced ROS production, which killed HCC cells via DNA damage that could not be repaired by Rad51. SUMMARY: PARPs and NF-κB are frequently deregulated in HCC. The DHMEQ-Olaparib combination exerted synergistic anti-tumour effects on HCC cells through ROS production via DNA damage that could not be repaired by Rad51. This suggested that the DHMEQ-Olaparib combination could be used to treat tumours that were resistant to Olaparib treatment.

Saffron and natural carotenoids: Biochemical activities and anti-tumor effects.

Saffron, a spice derived from the flower of Crocus sativus, is rich in carotenoids. Two main natural carotenoids of saffron, crocin and crocetin, are responsible for its color. Preclinical studies have shown that dietary intake of some carotenoids have potent anti-tumor effects both in vitro and in vivo, suggesting their potential preventive and/or therapeutic roles in several tissues. The reports represent that the use of carotenoids without the potential for conversion to vitamin A may provide further protection and avoid toxicity. The mechanisms underlying cancer chemo-preventive activities of carotenoids include modulation of carcinogen metabolism, regulation of cell growth and cell cycle progression, inhibition of cell proliferation, anti-oxidant activity, immune modulation, enhancement of cell differentiation, stimulation of cell-to-cell gap junction communication, apoptosis and retinoid-dependent signaling. Taken together, different hypotheses for the antitumor actions of saffron and its components have been proposed such as a) the inhibitory effect on cellular DNA and RNA synthesis, but not on protein synthesis; b) the inhibitory effect on free radical chain reactions; c) the metabolic conversion of naturally occurring carotenoids to retinoids; d) the interaction of carotenoids with topoisomerase II, an enzyme involved in cellular DNA-protein interaction. Furthermore, the immunomodulatory activity of saffron was studied on driving toward Th1 and Th2 limbs of the immune system. In this mini-review, we briefly describe biochemical and immunological activities and chemo-preventive properties of saffron and natural carotenoids as an anticancer drug.

MiR-570 inhibited the cell proliferation and invasion through directly targeting B7-H1 in hepatocellular carcinoma.

A recent study reported that miR-570 was the most important microRNA in the microRNA gene networks of alcoholic liver disease that has the potential of progressing to hepatocellular carcinoma. However, litter is known regarding the expression and specific function of miR-570 in the progression of hepatocellular carcinoma, especially its molecular mechanisms by which miR-570 exerts its functions and modulates the malignant phenotypes of hepatocellular carcinoma cells. Here, we observed that miR-570 was highly expressed in hepatocellular carcinoma cell lines (Bel-7404, Huh-7, and HepG2), while B7-H1 was lowly expressed, compared to nonmalignant cell line (L-02 and HL-7702). Transfection of miR-570 mimics or knockdown of B-H1 suppressed the expression of B7-H1, which promotes cell apoptosis and inhibits the cell proliferation and invasion. Using a dual-luciferase reporter system, we verified that B7-H1 is a direct target of miR-570. The overexpression of B7-H1 reversed the inhibition of proliferation and invasion by miR-570. In addition, miR-570 suppressed tumorigenicity in vivo. Hence, our observation confirmed that miR-570 works as proliferation and metastatic suppressor in hepatocellular carcinoma cells through directly targeting B7-H1 in hepatocellular carcinoma cell and rationally presents that miR-570 has the potential to be a useful clinical noninvasive diagnostics or predictive marker in human hepatocellular carcinoma.