QGY-7703 Cells Research Articles

Antitumour effects of tetrazanbigen against human hepatocellular carcinoma QGY-7701 through inducing lipid accumulation in vitro and in vivo.

Tetrazanbigen (TNBG) is a newly synthesized compound with an isoquinoline moiety, and its antitumour effects were evaluated in in-vitro and in-vivo models. 3-[4, 5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to measure the antiproliferative activity of TNBG on cancer cell lines. Antitumour activity of TNGB in vivo was also assessed in a xenograft model of human hepatocellular carcinoma QGY-7701 cell line. Cell cycle and cell apoptosis analysis was performed. TNBG exhibited strong antitumour efficacy against six human cancer cell lines with IC50 range of 2.13-8.01 μg/ml. The IC50 of TNBG on normal hepatic cells was 11.25 μg/ml. Lots of lipid droplets were observed in cytoplasm of human hepatocellular carcinoma QGY-7701 cells after treatment of TNBG. S phase arrest and apoptosis induction by TNBG were also found on QGY-7701 cells. Intraperitoneal injection of TNBG (1.5 mg/kg/day) resulted in significant decreases in tumour volume and tumour weight on nude mice bearing QGY-7701 cells xenografts. Results from pathological analysis in nude mice demonstrated that TNBG could induce lipid accumulation specifically in cancer tissue rather than in other normal organs, tissues and blood. These results suggested that TNBG might exert potent antitumour activity through inducing lipid accumulation in cancer cell.

Abstract 5400: A novel combinatorial therapy for hepatocellular carcinoma (HCC)

Abstract The incidence of hepatocellular carcinoma (HCC) is rising in the US with parallel increase in mortality rate. Lack of effective therapy for advanced HCC mandates development of novel targeted therapies to counteract this fatal malady. Astrocyte elevated gene-1 (AEG-1), also known as metadherin (MTDH) and LYRIC, plays a pivotal role in hepatocarcinogenesis and serves as an ideal target for anti-HCC therapy. AEG-1 interacts with retinoid X receptor (RXR) and inhibits retinoic acid-induced gene expression and cell death. Retinoic acid has been evaluated for HCC treatment without promising result. Overexpression of AEG-1 might underlie the poor performance of retinoic acid in HCC clinical trials. We documented that combination of a lentivirus expressing AEG-1 shRNA (lenti.shAEG-1) and all-trans retinoic acid (ATRA) profoundly and synergistically inhibited subcutaneous human HCC xenografts in nude mice. We now have developed liver-targeted nanoplexes by conjugating poly(amidoamine) (PAMAM) dendrimers with polyethylene glycol (PEG) and lactobionic acid (PAMAM-PEG-Gal) which were complexed with AEG-1 siRNA (PAMAM-AEG-1si). PAMAM has a net positive charge that complexes with the net negative charge of the siRNA backbone, PEG increases stability of the nanoplexes and increases circulation time and the galactose binds to asialoglycoprotein receptors that are upregulated on liver cells. The polymer conjugate was characterized by 1H-NMR and optimal nanoplex formulations were characterized for surface charge and size using a zetasizer Nano ZS. We established orthotopic xenografts of human HCC cell QGY-7703 expressing luciferase (QGY-luc) in the livers of athymic nude mice and monitored tumor development by bioluminescence imaging (BLI). One week after tumor establishment mice were treated with PAMAM-siCon, PAMAM-siCon+ATRA, PAMAM-AEG-1si and PAMAM-AEG-1si+ATRA by 8 i.v. injections over 4 weeks, and sacrificed 2 weeks after the last injection. In the control group the tumor developed aggressively. ATRA showed little effect due to high AEG-1 levels in QGY-luc cells. PAMAM-AEG-1si showed significant reduction in tumor growth and the combination of PAMAM-AEG-1si+ATRA showed profound and synergistic inhibition so that the tumors were almost undetectable by BLI. Measurement of liver weight at the end of the experiment corroborated these findings. Analysis of AEG-1 mRNA in tumor samples showed a marked decrease in AEG-1 level by PAMAM-AEG-1si indicating efficacy of in vivo knockdown. The group treated with PAMAM-AEG-1si+ATRA nanoplexes showed increased necrosis, inhibition of proliferation and increased apoptosis when compared to other groups. Liver is an ideal organ for RNAi therapy and ATRA is an approved anti-cancer agent. Our exciting observations suggest that the combinatorial approach might be an effective way to combat HCC and need to be evaluated stringently in endogenous mouse models of HCC for a potential Phase I/II clinical trial. Citation Format: Jyoti Srivastava, Devaraja Rajasekaran, Ayesha Siddiq, Rachel Gredler, Chadia L. Robertson, Maaged A. Akiel, Xue-Ning Shen, Kareem A.N. Ebeid, Aliasger K. Salem, Paul B. Fisher, Devanand Sarkar. A novel combinatorial therapy for hepatocellular carcinoma (HCC). [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5400. doi:10.1158/1538-7445.AM2015-5400

Combination of Nanoparticle-Delivered siRNA for Astrocyte Elevated Gene-1 (AEG-1) and All-trans Retinoic Acid (ATRA): An Effective Therapeutic Strategy for Hepatocellular Carcinoma (HCC).

Hepatocellular carcinoma (HCC) is a fatal cancer with no effective therapy. Astrocyte elevated gene-1 (AEG-1) plays a pivotal role in hepatocarcinogenesis and inhibits retinoic acid-induced gene expression and cell death. The combination of a lentivirus expressing AEG-1 shRNA and all-trans retinoic acid (ATRA) profoundly and synergistically inhibited subcutaneous human HCC xenografts in nude mice. We have now developed liver-targeted nanoplexes by conjugating poly(amidoamine) (PAMAM) dendrimers with polyethylene glycol (PEG) and lactobionic acid (Gal) (PAMAM-PEG-Gal) which were complexed with AEG-1 siRNA (PAMAM-AEG-1si). The polymer conjugate was characterized by (1)H-NMR, MALDI, and mass spectrometry; and optimal nanoplex formulations were characterized for surface charge, size, and morphology. Orthotopic xenografts of human HCC cell QGY-7703 expressing luciferase (QGY-luc) were established in the livers of athymic nude mice and tumor development was monitored by bioluminescence imaging (BLI). Tumor-bearing mice were treated with PAMAM-siCon, PAMAM-siCon+ATRA, PAMAM-AEG-1si, and PAMAM-AEG-1si+ATRA. In the control group the tumor developed aggressively. ATRA showed little effect due to high AEG-1 levels in QGY-luc cells. PAMAM-AEG-1si showed significant reduction in tumor growth, and the combination of PAMAM-AEG-1si+ATRA showed profound and synergistic inhibition so that the tumors were almost undetectable by BLI. A marked decrease in AEG-1 level was observed in tumor samples treated with PAMAM-AEG-1si. The group treated with PAMAM-AEG-1si+ATRA nanoplexes showed increased necrosis, inhibition of proliferation, and increased apoptosis when compared to other groups. Liver is an ideal organ for RNAi therapy and ATRA is an approved anticancer agent. Our exciting observations suggest that the combinatorial approach might be an effective way to combat HCC.

Hypermethylation of FOXD3 suppresses cell proliferation, invasion and metastasis in hepatocellular carcinoma

As a transcriptional repressor, forkhead box D3 (FOXD3) plays an important role in tumorigenesis and progression of several tumors. However, the function and methylation status of FOXD3 remain unknown in the progression of hepatocellular carcinoma (HCC). In this study, we found that FOXD3 was decreased in HCC tissues and correlated with differentiation, AFP and poor survival of HCC patients (p<0.05). Down-regulation of FOXD3 in HCC tissues was mainly due to promoter hypermethylation. In vitro and in vivo functional results showed that ectopic FOXD3 inhibited the proliferation, migration, epithelial–mesenchymal transition (EMT) and invasion in HepG2 and SMMC-7721 cells, and FOXD3 depletion in HepG2 and QGY-7701 cells showed the adverse effects (p<0.05). Moreover, FOXD3 was sufficient to suppress tumor growth and pulmonary metastatic potential in mice. Our findings suggest that down-regulation of FOXD3, due to promoter hypermethylation plays an important role in the progression of HCC and may be a promising prognostic biomarker for HCC patients.

RASSF10 suppresses hepatocellular carcinoma growth by activating P53 signaling and methylation of RASSF10 is a docetaxel resistant marker.

Hepatocellular carcinoma (HCC) is one of the most common malignances and the second leading cause of cancer related death worldwide. RASSF10 is located on chromosome 11p15.2, a region that shows frequent loss of heterozygosity (LOH) in several cancer types. Our previous study found that RASSF10 suppresses colorectal cancer growth by activating P53 signaling. To explore the epigenetic changes and the mechanism of RASSF10 in human HCC, 69 cases of primary HCC, twenty cases of normal liver tissue samples and 17 HCC cell lines were involved in this study. We found that RASSF10 was methylated in 82.6% (57/69) of human primary HCC and methylation of RASSF10 was significantly associated with tumor size (P < 0.05) and TNM stage (P < 0.05). The expression of RASSF10 was regulated by promoter region methylation. Restoration of RASSF10 expression suppressed cell proliferation, induced apoptosis and G2/M phase arrest, as well as sensitized cells to docetaxel and activated P53 signaling in HepG2 and QGY7703 cells. In conclusion, we demonstrated that RASSF10 is frequently methylated in human HCC and its methylation is a potential docetaxel resistant marker. Our data also indicate that RASSF10 suppresses human HCC growth by activating P53 signaling.

MiR-20a Induces Cell Radioresistance by Activating the PTEN/PI3K/Akt Signaling Pathway in Hepatocellular Carcinoma

To investigate the role of miR-20a in hepatocellular carcinoma (HCC) cell radioresistance, which may reveal potential strategies to improve treatment. The expression of miR-20a and PTEN were detected in HCC cell lines and paired primary tissues by quantitative real-time polymerase chain reaction. Cell radiation combined with colony formation assays was administrated to discover the effect of miR-20a on radiosensitivity. Bioinformatics prediction and luciferase assay were used to identify the target of miR-20a. The phosphatidylinositol 3-kinase inhibitor LY294002 was used to inhibit phosphorylation of Akt, to verify whether miR-20a affects HCC cell radioresistance through activating the PTEN/PI3K/Akt pathway. MiR-20a levels were increased in HCC cell lines and tissues, whereas PTEN was inversely correlated with it. Overexpression of miR-20a in Bel-7402 and SMMC-7721 cells enhances their resistance to the effect of ionizing radiation, and the inhibition of miR-20a in HCCLM3 and QGY-7701 cells sensitizes them to it. PTEN was identified as a direct functional target of miR-20a for the induction of radioresistance. Overexpression of miR-20a activated the PTEN/PI3K/Akt signaling pathway. Additionally, the kinase inhibitor LY294002 could reverse the effect of miR-20a-induced radioresistance. MiR-20a induces HCC cell radioresistance by activating the PTEN/PI3K/Akt pathway, which suggests that miR-20a/PTEN/PI3K/Akt might represent a target ofinvestigation for developing effective therapeutic strategies against HCC.

Functionalized Graphene Oxide with Hepatocyte Targeting as Anti-Tumor Drug and Gene Intracellular Transporters.

In order to realize the hepatocyte-specific targeted delivery of anti-tumor drug and gene, lactosylated chitosan oligosaccharide (LCO) functionalized graphene oxides (GO-LCO) containing quaternary ammonium groups (GO-LCO+) were prepared. The formation and composition of GO-LCO+ were confirmed by FTIR, AFM, TGA and zeta-potential. The in vitro cells uptakes of this functionalized GO were investigated and the results showed that GO-LCO+ can deliver fluorescein FAM-labeled DNA sequence (FAM-DNA) into human hepatic carcinoma cells (QGY-7703) with higher efficiency than positively charged chitosan oligosaccharide (CO) functionalized graphene oxides (GO-CO+) without Lactose acid modification. The loading efficiency of doxorubicin chloride (Dox) on GO-LCO+ with 477 µg/mg was obtained at the initial Dox concentration of 0.45 mg/ml and release of Dox on GO-LCO+ showed strong pH dependence. The toxicity of GO-LCO+ before and after loading with Dox toward QGY-7703 cells was further investigated. Our results suggest the functionalized GO to be used as a nanocarrier for hepatocyte targeted co-delivery of anti-tumor drugs and genes with low cytotoxicity, promising for future applications in anticancer drug and gene combined therapy.

Notch3 functions as a regulator of cell self-renewal by interacting with the β-catenin pathway in hepatocellular carcinoma.

The Notch signaling pathway plays a role in cell proliferation, differentiation. Emerging data have revealed aberrant Notch3 expression in hepatocellular carcinoma (HCC). However, whether Notch3 plays a role in tumorigenesis or tumor progression is unclear. In this study, we found that over 71.8% of the cases studied had high Notch3 expression levels (n = 32); Notch3 expression positively correlated with alpha-fetoprotein (AFP) levels (p = 0.0311) and negatively correlated with the differentiation grade (p = 0.042). We demonstrated that the patients with higher levels of Notch3 expression commonly had a poor prognosis. We discovered that Notch3 expression is inversely correlated with β-catenin content but positively associated with the protein level of Nanog. In parallel, we found that Notch3 attenuation resulted in the upregulation of β-catenin and the downregulation of Nanog in the hepatoma cell lines QGY7701 and HepG2. The downregulation of Notch3 enhanced the sensitivity to cisplatin in the QGY7701 and HepG2 cells and inhibited the ability of QGY7701 cells to form tumors. The Notch3-positive cells had higher levels of aldehyde dehydrogenase (ALDH) activity, and a tendency to differentiate into Notch3-negative cells. In conclusion, our study demonstrated that Notch3 plays a role in modulating the stemness of tumor cells via the inactivation of the Wnt/β-catenin pathway.

HOXA7 stimulates human hepatocellular carcinoma proliferation through cyclin E1/CDK2.

HOX genes are transcription factors that control morphogenesis, organogenesis and differentiation. Increasing evidence suggests that HOX genes play a role in hepatocellular carcinoma (HCC) progression; however few studies have defined the functional roles and mechanisms of action. In the present study, we used siRNA and forced-expression in multiple cell lines to define the role of HOXA7 in the regulation of proliferation of HCC in vitro and in vivo. Knockdown of endogenous HOXA7 decreased the proliferation of HepG2 and QGY-7703 cells. These changes were not associated with significant changes in cyclin D1 and CDK4. However, downregulation of HOXA7 significantly reduced cyclin E1 and CDK2 protein levels. Conversely, overexpression of HOXA7 in QSG-7701 cells stimulated proliferation and increased cyclin E1 and CDK2 protein levels. Our results confirmed that HOXA7 promoted cell proliferation, and these changes were mediated by cyclin E1/CDK2. These observations contribute to our understanding of the important roles of HOXA7 in HCC development and progression and HOXA7 could be a promising molecular target for the development of new diagnostic and therapeutic strategies for HCC.

Mir-509-5p joins the Mdm2/p53 feedback loop and regulates cancer cell growth.

Although the Mdm2/p53 interaction has been well documented, it is not clear whether there are new microRNAs participating in this regulatory network. Here, we provide evidence that miR-509-5p, which is downregulated in a subset of newly diagnosed cervical cancer and hepatocellular carcinoma tissues compared with the adjacent nontumor tissue, can be activated by p53 through binding the promoter of miR-509-5p and it suppresses the growth and invasion/migration of cervical cancer and hepatoma cells by regulating apoptosis and the G1/S-phase transition of cell cycle. Furthermore, Mdm2 was identified to be a target of miR-509-5p by targeting its 3′-UTR. Restoration of Mdm2 abrogated the cell phenotypes induced by miR-509-5p. Moreover, ectopic expression of miR-509-5p in HeLa and QGY-7703 cells repressed the expression of Mdm2, subsequently enhancing its p53-activating effects. These results suggest that miR-509-5p is a new regulator of Mdm2/p53 pathway and may play a key role in cancer development.

Effects of miR-106b expression on the proliferation of human hepatocellular carcinoma cells

To investigate the effects of miR-106b expression on the proliferation of human hepatocellular carcinoma cells. Real-time PCR was used to detect the expression of miR-106b in human hepatocellular carcinoma (HCC) cell lines and normal liver epithelial THLE3 cells. Over-expression of miR-106b was transfected by miR-106b mimics, and inhibition of miR-106b expression was transfected by miR-106b inhibitors. The effects of miR-106b expression on the proliferation of HCC cells were detected by MTT, clone formation assay and anchorage-independent growth ability assay. Bromodeoxyuridine labeling and flow cytometry analysis were used to examine the effects of miR-106b expression on the cell cycle distribution of the HCC cells. Compared with that in the normal liver epithelial THLE3 cells, the relative expression of miR-106b in HepG2, QGY-7703, BEL-7402, MHCC97H, HCCC-9810, Hep3B, MHCC97L and Huh7 cell lines were 5.37 ± 0.35, 8.45 ± 0.75, 19.22 ± 1.74, 11.93 ± 1.26, 17.03 ± 0.97, 4.19 ± 0.67, 7.94 ± 1.35 and 3.82 ± 0.87, respectively (P < 0.05 for all). Three days after transfection, the miR-106b over-expression was accelerated, while miR-106b inhibitor suppressed the proliferation of HCC cells. The numbers of clones formed were (4.13 ± 0.75) and (3.78 ± 0.47) times higher than that of control cells, and (147.73 ± 15.56) and (138.87 ± 15.58) clones in diameter >1.0 mm were formed by miR-106b-overexpressing cells. When the miR-106b expression was inhibited in the HepG2 and QGY-7703 cells, the clone numbers were (0.18 ± 0.05) and (0.24 ± 0.07) times of that in the controls, and the numbers of clones formed were (23.29 ± 7.14) and (20.60 ± 8.07) (P < 0.05 for all). The positive rates of BrdU labeled miR-106b-overexpressing HepG2 and QGY-7703 cells were (51.89 ± 4.91) % and (54.74 ± 6.10) %, those of the miR-106b-inhibited cells were (6.48 ± 3.15) % and (7.52 ± 2.03) %, significantly different from that in the control cells (P < 0.05 for all). The S phases were dramatically increased from 29.93% and 31.04% to 56.76% and 57.22% in the miR-106b-overexpressing HepG2 and QGY-7703 cells, while they were 19.43% and 19.92% in the miR-106b-inhibited HepG2 and QGY-7703 cells. MiR-106b overexpression may promote the proliferation and metastasis of HCC cells. The mechanism of this effect may be related to promoting cells into S phase and inhibiting cell apoptosis.

N-Glycosylation Is Required for Matriptase-2 Autoactivation and Ectodomain Shedding

Matriptase-2 is a hepatic membrane serine protease that regulates iron homeostasis. Defects in matriptase-2 cause iron deficiency anemia. In cells, matriptase-2 is synthesized as a zymogen. To date, how matriptase-2 expression and activation are regulated remains poorly understood. Here we expressed human matriptase-2 in HEK293 and hepatic BEL-7402, SMMC-7721, and QGY-7703 cells. By labeling cell surface proteins and Western analysis, we examined matriptase-2 cell surface expression, zymogen activation, and ectodomain shedding. Our results show that matriptase-2 was activated on the cell surface but not intracellularly. Activated matriptase-2 underwent ectodomain shedding, producing soluble fragments in the conditioned medium. By testing inactive mutants, R576A and S762A, we found that matriptase-2 activation and shedding were mediated by its own catalytic activity and that the one-chain form of matriptase-2 had little activity in ectodomain shedding. We made additional matriptase-2 mutants, N136Q, N184Q, N216Q, N338Q, N433Q, N453Q, and N518Q, in which each of the predicted N-glycosylation sites was mutated. All of these mutants were expressed on the cell surface. However, mutants N216Q, N453Q, and N518Q, but not the other mutants, had impaired zymogen activation and ectodomain shedding. Our results indicate that N-glycans at specific sites are critical for matriptase-2 activation. Together, these data provide new insights into the cell surface expression, zymogen activation, and ectodomain shedding of matriptase-2.

MicroRNA-452 promotes tumorigenesis in hepatocellular carcinoma by targeting cyclin-dependent kinase inhibitor 1B

Dysregulation of miR-452 has been observed in many tumors, but its biological function in hepatocellular carcinoma (HCC) is still unknown. Our results showed that miR-452 expression is significantly increased in HCC tissues and HCC cell lines. We also found that overexpression of miR-452 dramatically accelerated proliferation, induced cell cycle from G1 to S transition, and blocked apoptosis of HCC cells. Migration and matrigel invasion assays indicated that miR-452 significantly promotes HepG2 and QGY-7703 cells migration and invasion in vitro. Further studies showed that miR-452 directly targets the 3'-untranslated region of cyclin-dependent kinase inhibitor 1B (CDKN1B), ectopic miR-452 expression suppressed CDKN1B expression on mRNA and protein level. Silencing CDKN1B by small interfering RNA resembled the phenotype resulting from ectopic miR-452 expression. This study provides new insights into the potential molecular mechanisms that miRNA-452 contributed to HCC.

Downregulation of miR-7 upregulates Cullin 5 (CUL5) to facilitate G1/S transition in human hepatocellular carcinoma cells

MicroRNAs (miRNAs) are small, non-coding RNAs that participate in the regulation of gene expression. In this study, we demonstrate that miR-7 was downregulated in hepatocellular carcinoma (HCC) tissues compared to adjacent non-tumor tissue. Over-expression of miR-7 in QGY-7703 and HepG2 cell lines inhibited colony formation and induced G1/S phase arrest, whereas knockdown of miR-7 produced the opposite phenotype. A tumor suppressor gene, CUL5, was identified as a direct target of miR-7, and CUL-5 is upregulated upon the binding of miR-7 to its 3'UTR. Furthermore, suppression of CUL5 also suppressed cell colony formation and induced cell cycle arrest. Ectopic expression of CUL5 abrogated the effects of miR-7 inhibition on QGY-7703 and HepG2 cell lines. These results indicate that miR-7 suppresses colony formation and causes cell cycle arrest via upregulation of CUL5, and it may function as a tumor suppressor in HCC.

Synthesis and biological evaluation of phenyl substituted polyoxygenated xanthone derivatives as anti-hepatoma agents

A series of novel derivatives of phenyl substituted tetramethoxy xanthone were synthesized and evaluated for their in vitro cytotoxicity against human hepatocellular carcinoma (HCC) and non-tumor hepatic cells. Among these derivatives, compound 6 was more potent than positive control 5-fluorouracil (5-Fu) on QGY-7703 and SMMC-7721 cells with IC50 values of 6.27 μM, 7.50 μM and 15.56 μM, 14.55 μM, respectively. Furthermore, compounds 6, 14, 16, and 29 exhibited much better selectivity toward the normal hepatic cell line QSG-7701 than 5-Fu. Additionally, compound 6 significantly induced cell apoptosis in QGY-7703 cells. Our findings suggested that these phenylxanthone derivatives may hold promise as chemotherapeutic agents for the treatment of human HCC.

PREPARATION AND CHARACTERIZATION OF GLYCYRRHETINIC ACID-MODIFIED POLOXAMER 188/CHITOSAN NANOPARTICLES

In this paper, we firstly synthesized glycyrrhetinic acid-modified double amino-terminated poloxamer 188 (GA–NH–POLO–NH–GA). The structure of the synthesized compound was confirmed by 1H-NMR and Fourier transform infrared (FT-IR) spectroscopy. Then the nanoparticles composed of GA–NH–POLO–NH–GA/chitosan (GA–NH–POLO–NH–GA/CTS) were prepared by an ionic gelation process. The characterization of the nanoparticles was measured by dynamic light scattering (DLS) and scanning electron microscope (SEM). The results showed that the nanoparticles were well dispersed with a spherical shape and the particle size was distributed between 100 nm and 300 nm. The cytotoxicity based on MTT assay against cells (QGY-7703 cells and L929 cells) showed that the nanoparticles had low toxicity and good biocompatibility. The encapsulation efficiency and drug loading of 5-fluorouracil-loaded nanoparticles (5-FU nanoparticles) were measured by high-performance liquid chromatography (HPLC) and fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorbance. The encapsulation of 5-Fu-loaded CTS nanoparticles was 12.8% and the drug loading was 2.9%, while the encapsulation of 5-Fu-loaded GA–NH–POLO–NH–GA/CTS nanoparticles was 20.9% and the drug loading was 3.36%. The release profile showed that the GA–NH–POLO–NH–GA/CTS nanoparticles were available for sustained release of 5-Fu. The GA–NH–POLO–NH–GA/CTS nanoparticles have a higher affinity to the QGY-7703 cells, so indicated that the GA–NH–POLO–NH–GA/CTS nanoparticles have the capacity of liver-targeting in vitro.

Responses of the Antioxidant System in QGY‐7701 Cells to the Cytotoxicity and Apoptosis Induced by 1‐Octyl‐3‐methylimidazolium Chloride

This study aims to evaluate the cytotoxicity and responses of the cellular antioxidant system of 1-octyl-3-methylimidazolium chloride ([C8 mim][Cl]) on human hepatocarcinoma QGY-7701 cells. The results show that [C8 mim][Cl] can inhibit QGY-7701 cell growth and decrease their viabilities in a dose-dependent manner. The results also reveal that [C8 mim][Cl] exposure can induce apoptosis in the [C8 mim][Cl]-treated QGY-7701 cells. In addition, the results of biochemical assays show that [C8 mim][Cl] exposure causes overproduction of reactive oxygen species (ROS), inhibits superoxide dismutase (SOD) and catalase (CAT) activities, decreases reduced glutathione (GSH) content, and increases the cellular malondialdehyde (MDA) level. These results suggest that ROS-mediated oxidative stress may be responsible for the apoptosis induced by [C8 mim][Cl] in QGY-7701 cells.

MicroRNA 21‐mediated suppression of sprouty1 by Pokemon affects liver cancer cell growth and proliferation

Transcriptional repressor Pokemon is a critical factor in embryogenesis, development, cell proliferation, differentiation, and oncogenesis, thus behaving as an oncogene. Oncomine database suggests a potential correlation between the expressions of Pokemon and Sprouty1. This study investigated the regulatory role of Pokemon in Sprouty1 expression and the effect on liver cancer cell growth and proliferation, revealing a novel miR-21-mediated regulatory circuit. In normal (HL-7702) and cancer (QGY-7703) liver cell lines, Sprouty1 expression is inversely correlated with Pokemon levels. Targeted expression or siRNA-mediated silencing showed that Pokemon is a repressor of Sprouty1 expression at both mRNA and protein levels, but Pokemon cannot affect the promoter activity of Sprouty1. Sprouty1 is a target of miR-21 and interestingly, we found that miR-21 is up-regulated by Pokemon in liver cancer cells. Luciferase reporter assays showed that Pokemon up-regulated miR-21 transcription in a dose-dependent manner, and ChIP assay exhibited a direct binding of Pokemon to the miR-21 promoter at -747 to -399 bp. Site-directed mutagenesis of the GC boxes at -684 to -679 bp and -652 to -647 bp of miR-21 promoter abolished the regulatory activity by Pokemon. Furthermore, we found that the modulation of Pokemon and miR-21 expression affected the growth and proliferation of liver cancer cells QGY-7703. In summary, our findings demonstrate that Pokemon suppresses Sprouty1 expression through a miR-21-mediated mechanism, affecting the growth and proliferation of liver cancer cells. This study recognized miR-21 and Sprouty1 as novel targets of the Pokemon regulatory network.

A preliminary study of the inhibitive efficacy of iodized linoleic acid and its fluorodeoxyuridine ester in hepatocellular cancer

To explore the potential of iodized linoleic acid (ILA) and its 5-fluoro-deoxyuridine ester (IFU) to inhibit hepatocellular carcinoma (HCC) cells in vitro and tumors in vivo. ILA and its constituent component IFU were chemically synthesized, purified, and confirmed by 1H-NMR. The HCC cell lines, QGY-7703 (5-fluorouracil (5-FU) treatment sensitive) and SMMC-7721 (5-FU resistant), were treated with ILA, IFU, 5-FU, or traditional lipiodol for 72 hours. Survival rates of the treated cells were assessed by the methyl thiazolyl tetrazolium method, and used to calculate the IC50 and IC90. In addition, thirty nude mice were subcutaneously inoculated with SMMC-7721 cells and randomly divided two weeks later into four treatment groups (n = 6 each) for intra-tumoral injection of ILA, IFU, 5-FU, lipiodol or DMSO (controls). The rate of tumor inhibition (RTI) was calculated for each group at week 4 after treatment. For the cultured SMMC-7721 cells, the inhibitory concentrations for ILA, IFU, and 5-FU were: IC50: 134.38 mumol/L, 17.55 mumol/L, and 7.38 mumol/L; IC90: 192.88 mumol/L, 97.63 mumol/L, and more than 200 mumol/L. For the cultured QGY-7703 cells, the inhibitory concentrations for ILA, IFU, and 5-FU were: IC50: 109.55 mumol/L, 44.79 mumol/L, and 98.06 mumol/L; IC90: all, more than 200 mumol/L. In both cell types, the IC50 of lipiodol was more than 400 mumol/L. Compared with the RTI of the control mice (100%), the RTI of ILA-treated mice was 31.9% (t = 2.37, P less than 0.05), of IFU-treated mice was 56.9% (t = 4.91, P less than 0.01), and of 5-FU-treated mice was 31.0% (t = 2.59, P less than 0.05). The RTI of IFU was significantly stronger than that of either ILA or 5-FU (P less than 0.05). The lipiodol treatment showed no inhibition effect on tumors (P more than 0.05). ILA and IFU can effectively inhibit the growth of HCC cells in vitro and tumors in vivo. Furthermore, IFU outperforms ILA in inhibiting HCC growth.

Efficient Total Synthesis and Biological Activities of 6‐Deoxyisojacareubin

6-Deoxyisojacareubin was directly synthesized in a six-step route with an overall yield of about 20%. In this route, the excellent site selectivity of this Claisen rearrangement-cyclization reaction cascade was achieved by inserting a bulky p-tosyl group into the free 1-OH, and in the last step, some efficient demethylation methods were explored. Furthermore, all synthesized intermediates including 6-deoxyisojacareubin were evaluated for their inhibitory activity against the QGY-7703 cell line. Of these, compound 1 and 6-deoxyisojacareubin showed moderate activities with IC50 values of 39.61 and 9.65 µM, respectively, when compared to the positive control 5-fluorouracil with an IC50 value of 11.24 µM. Further investigation using non-radioactive detection of protein kinase C (PKC) suggested that these two compounds possessed potency in the inhibition of PKC.