benzofurans and Carcinoma--Hepatocellular

Cancer is a leading cause of death which imposes a substantial financial burden. Among the several mechanisms involved in cancer progression, imbalance of immune cell-derived factors such as cytokines and chemokines plays a central role. IL-25, as a member of the IL-17 cytokine subfamily, exerts a paradoxical role in cancer, including tumor supportive and tumor suppressive. Hence, we have tried to clarify the role of IL-25 and its receptor in tumor progression and cancer prognosis. It has been confirmed that IL-25 exerts a tumor-suppressive role through inducing infiltration of eosinophils and B cells into the tumor microenvironment and activating the apoptotic pathways. In contrast, the tumor-supportive function has been implemented by activating inflammatory cascades, promoting cell cycle, and inducing type-2 immune responses. Since IL-25 has been dysregulated in tumor tissues and this dysregulation is involved in cancer development, its examination can be used as a tumor diagnostic and prognostic biomarker. Moreover, IL-25-based therapeutic approaches have shown promising results in cancer inhibition. In cancers in which IL-25 has a tumor-suppressive function, employing IL-25-enhancing approaches, such as Virulizin

Topics: Animals; Antineoplastic Agents; Apoptosis; Benzofurans; Bile; Biomarkers, Tumor; Breast Neoplasms; Carcinoma, Hepatocellular; Cell Cycle; Cell Proliferation; Disease Progression; Female; Humans; Immunity, Cellular; Interleukin-17; Liver Neoplasms; Male; Mice; Neoplasms; Prognosis; Prostatic Neoplasms; Receptors, Interleukin-17; Signal Transduction; Tissue Extracts; Tumor Microenvironment

For patients with advanced hepatocellular carcinoma (HCC), the standard of care for many years has been sorafenib. Preliminary data have suggested that the combination of the NAD(P)H:quinone oxidoreductase 1 bioactivatable agent napabucasin plus sorafenib may improve clinical outcomes in patients with HCC. In this phase I, multicenter, uncontrolled, open-label study, we evaluated napabucasin (480 mg/day) plus sorafenib (800 mg/day) in Japanese patients with unresectable HCC.. Adults with unresectable HCC and an Eastern Cooperative Oncology Group performance status of 0 or 1 were enrolled in a 3 + 3 trial design. The occurrence of dose-limiting toxicities was assessed through 29 days from the start of napabucasin administration. Additional endpoints included safety, pharmacokinetics, and preliminary antitumor efficacy.. In the six patients who initiated treatment with napabucasin, no dose-limiting toxicities occurred. The most frequently reported adverse events were diarrhea (83.3%) and palmar-plantar erythrodysesthesia syndrome (66.7%), all of which were grade 1 or 2. The pharmacokinetic results for napabucasin were consistent with prior publications. The best overall response (per Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1) was stable disease in four patients. Using Kaplan-Meier methodology, the 6-month progression-free survival rate was 16.7% per RECIST 1.1 and 20.0% per modified RECIST for HCC. The 12-month overall survival rate was 50.0%.. These findings confirm the viability of napabucasin plus sorafenib treatment, and there were no safety or tolerability concerns in Japanese patients with unresectable HCC.. ClinicalTrials.gov identifier NCT02358395, registered on 9 February 2015.

Topics: Adult; Antineoplastic Combined Chemotherapy Protocols; Benzofurans; Carcinoma, Hepatocellular; East Asian People; Humans; Liver Neoplasms; Naphthoquinones; Sorafenib

The role and significance of liver-derived cytokines in cancer-associated cachexia syndrome remain elusive. Here we report that combinatorial counterbalances of the leptin and Igf1 signaling pathways in hepatocellular carcinoma (HCC) models significantly relieves cachexia. Double transgenic zebrafish models of HCC that stably displayed focal lesions, anorexia, and wasting of adipose and muscle tissues were first generated. Knockout of lepr or mc4r from these zebrafish partially restored appetite and exerted moderate or no effect on tissue wasting. However, genetic replenishment of Igf1 in a lepr-mutant background effectively relieved the cachexia-like phenotype without affecting tumor growth. Similarly, administration of napabucasin, a Stat3/Socs3 inhibitor, on the zebrafish HCC model, mammalian cell lines with exogenous IGF1, and two mouse xenograft models restored insulin sensitivity and rescued the wasting of nontumor tissues. Together, these results describe the synergistic impact of leptin and Igf1 normalization in treating certain HCC-associated cachexia as a practical strategy. SIGNIFICANCE: Disruption of leptin signaling with normalized Igf1 expression significantly rescues anorexia, muscle wasting, and adipose wasting in Ras- and Myc-driven zebrafish models of HCC.

Topics: 3T3-L1 Cells; Adipose Tissue; Animals; Animals, Genetically Modified; Benzofurans; Cachexia; Carcinoma, Hepatocellular; Cells, Cultured; Cytokines; Disease Models, Animal; Drug Synergism; HEK293 Cells; Hep G2 Cells; Humans; Insulin Resistance; Insulin-Like Growth Factor I; Leptin; Liver; Liver Neoplasms; Mice; Muscular Atrophy; Naphthoquinones; Receptors, Leptin; Signal Transduction; Wasting Syndrome; Xenograft Model Antitumor Assays; Zebrafish

To repurpose therapeutics for fibrolamellar carcinoma (FLC), we developed and validated patient-derived xenografts (PDX) from surgical resections. Most agents used clinically and inhibitors of oncogenes overexpressed in FLC showed little efficacy on PDX. A high-throughput functional drug screen found primary and metastatic FLC were vulnerable to clinically available inhibitors of TOPO1 and HDAC and to napabucasin. Napabucasin's efficacy was mediated through reactive oxygen species and inhibition of translation initiation, and specific inhibition of eIF4A was effective. The sensitivity of each PDX line inversely correlated with expression of the antiapoptotic protein Bcl-xL, and inhibition of Bcl-xL synergized with other drugs. Screening directly on cells dissociated from patient resections validated these results. This demonstrates that a direct functional screen on patient tumors provides therapeutically informative data within a clinically useful time frame. Identifying these novel therapeutic targets and combination therapies is an urgent need, as effective therapeutics for FLC are currently unavailable. SIGNIFICANCE: Therapeutics informed by genomics have not yielded effective therapies for FLC. A functional screen identified TOPO1, HDAC inhibitors, and napabucasin as efficacious and synergistic with inhibition of Bcl-xL. Validation on cells dissociated directly from patient tumors demonstrates the ability for functional precision medicine in a solid tumor.

Topics: Aniline Compounds; Animals; Antineoplastic Agents; Benzofurans; Carcinoma, Hepatocellular; Female; Gene Expression Regulation, Neoplastic; Humans; Liver Neoplasms; Male; Mice; Naphthoquinones; Sulfonamides; Xenograft Model Antitumor Assays

Topics: Antineoplastic Agents; Benzofurans; Carcinoma, Hepatocellular; Cell Survival; Hep G2 Cells; Humans; Lactones; Liver Neoplasms; Microalgae; Molecular Structure; Monoterpenes

Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) participates in diverse cancer-associated signaling pathways, playing an oncogenic role in multiple human cancers, including hepatocellular carcinoma (HCC). Our recent works clarify that Pin1 modulates miRNAs biogenesis by interacting with ERK-phosphorylated exportin-5 (XPO5) and changing XPO5 conformation, giving a potential target for HCC treatment. Herein, we discover 4,6-bis(benzyloxy)-3-phenylbenzofuran (TAB29) as a novel Pin1 inhibitor that targets Pin1 PPIase domain. TAB29 potently inhibits Pin1 activity with the IC

Topics: Antineoplastic Agents; Benzofurans; Binding Sites; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Humans; Karyopherins; Liver Neoplasms; MicroRNAs; Molecular Docking Simulation; NIMA-Interacting Peptidylprolyl Isomerase; Protein Binding; Up-Regulation

Usnic acid (UA) is a multifunctional bioactive lichen secondary metabolite with potential anti-cancer properties. Although the promising therapeutic effects of UA have been investigated in different cancer cell lines, the mechanism driving UA-induced cell death has yet to be elucidated. As the type of cell death (apoptosis or autophagy) induced by UA may vary depending on the cancer cell type, we first studied the cytotoxic effects of UA in HEPG2 (HBV(-)) and SNU-449(HBV(+)) hepatocellular carcinoma (HCC) cell lines. HCC cell viability was considerably reduced in a dose-dependent manner at 12, 24, and 48 h after treatment with UA ( p < 0.05). However, SNU-449 cells were more sensitive to UA than HEPG2 cells. UA also induced apoptotic cell death in HCC cells with cell cycle arrest at G0/G1 and G2/M phase depending on the genetic profile of each cell type. On the other hand, we observed acidic vesicular organelles in HCC cells after 36 h of UA treatment. Taken together, these findings suggest that UA stimulates apoptosis and autophagy in HEPG2 and SNU-449 cells without damaging normal control cells. Thus, UA might be a potential therapeutic compound for HCC treatment. However, there is a need for further studies investigating the death-promoting or preventing roles for autophagy and the molecular signaling mechanisms induced by UA treatment.

Topics: Antineoplastic Agents; Apoptosis; Autophagy; Benzofurans; Carcinoma, Hepatocellular; Cell Cycle Checkpoints; Cell Line, Tumor; Humans; Liver Neoplasms

Sorafenib (SOR) is an orally administered molecular targeted agent in the systemic chemotherapy of hepatocellular carcinoma (HCC). However, the partial response of SOR is limited due to its adverse side effect and high heterogeneity and resistant phenotype of HCC. In the current study, we investigated synergistic effects of SOR and usnic acid (UA) on HCC cell lines including HepG2 and SNU-449, and a normal cell line, HUVEC.. The antiproliferative and apoptotic effects of combination therapy and SOR alone were analysed by WST-1 and Annexin V analysis, respectively. Furthermore, cell cycle, gene expression analysis of SOR-targeted kinases and acridine orange-ethidium bromide staining were also performed in combined treatments.. Our results demonstrated that SOR and UA combination indicated a strong synergism in HCC cell lines and reduced SOR toxicity in HUVEC cells. Additionally, the combination treatment SOR and UA significantly induced much more apoptotic cell death and G0/G1 arrest through downregulation of SOR-targeted kinases.. Consequently, SOR and UA combination could be a new therapeutic strategy for HCC treatment.

Topics: Annexin A5; Antineoplastic Agents; Apoptosis; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Drug Synergism; Drug Therapy, Combination; Hep G2 Cells; Humans; Liver Neoplasms; Protein-Tyrosine Kinases; Sorafenib

Manipulating the posttranslational modulator of p53 is central in the regulation of its activity and function. ISGylated p53 can be degraded by the 20S proteasome. During this process, HERC5/Ceb1, an IFN-induced HECT-type E3 ligase, mediated p53 ISGylation. In this study, we indicated that HERC5 was over-expressed in both HCC tissue samples and cell lines. Knockdown of HERC5 significantly induced the expression of p53, p21 and Bax/Bcl-2 in HCC cells, resulting in apoptosis augment. Whereas, opposite results were obtained by using HERC5 over-expression. On this basis, we screened a 7, 11-disubstituted quinazoline derivative HZ-6d that could bind to the HERC5 G-rich sequence in vitro. Interestingly, HZ-6d injection effectively delayed the growth of xenografts in nude mice. In vitro, HZ-6d significantly inhibited cell growth, suppressed cell migration, induced apoptosis in HCC cells. Further studies demonstrated the anti-cancer effect of HZ-6d was associated with down-regulation of HERC5 and accumulation of p53. Collectively, we demonstrated that HZ6d is a HERC5 G-quadruplex ligand with anti-tumor properties, an action that may offer an attractive idea for restoration of p53 function in cancers.

Topics: Antineoplastic Agents; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Drug Delivery Systems; Gene Expression Regulation, Neoplastic; Humans; Intracellular Signaling Peptides and Proteins; Liver Neoplasms; Quinazolines; Tumor Suppressor Protein p53

3,5-Dimethyl-

Topics: Animals; Antineoplastic Agents; Apoptosis; bcl-2 Homologous Antagonist-Killer Protein; bcl-2-Associated X Protein; Bcl-2-Like Protein 11; Benzofurans; Carcinoma, Hepatocellular; Coumarins; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Hep G2 Cells; Humans; Liver Neoplasms; Mice; Mice, Nude; Molecular Structure; Myeloid Cell Leukemia Sequence 1 Protein; Neoplasm Proteins; Protein Conformation; Proto-Oncogene Proteins c-bcl-2; RNA Interference; Transcription, Genetic; Xenograft Model Antitumor Assays

Usnic acid (UA) can be found in certain lichen species. Growing evidence suggests that UA possesses antitumoral, antioxidative and anti-inflammatory activities. Bleomycin (BLM) is widely used in the treatment of malignant ascites, however, it unexpectedly causes pulmonary fibrosis (PF). Researches show that excessive inflammatory response and oxidative stress in lung tissue is conspicuous causes of BLM-induced PF. Here we investigated mechanism underlying the effect-enhancing and toxicity-reducing activity of UA on H22-bearing mice treated with BLM. UA combined with BLM was significantly more effective than BLM alone in inhibiting the tumor growth, arresting the cell cycle at G0/G1 phase, and promoting the cleaved caspase-3 and cleaved caspase-8 activities to induce cancer cellular apoptosis. The mechanism may be associated with the transcriptional regulation of p53/p21/Cyclin pathway. Furthermore, UA effectively moderated the histopathological changes, reduced the content of MDA, HYP, TNF-α, IL-1β, IL-6 and TGF-β1, and increased the level of SOD when combined with BLM in lung tissues of H22-bearing mice, which was believed to be related to the inhibition on the protein level of p-Smad2/3 and enhancement of Smad7 expression. These findings suggested that UA might be a potential effect-enhancing and toxicity-reducing candidate for BLM in the treatment of malignant ascites.

Topics: Adjuvants, Pharmaceutic; Animals; Antineoplastic Agents; Apoptosis; Ascites; Benzofurans; Bleomycin; Carcinoma, Hepatocellular; Cell Cycle Checkpoints; Cell Line, Tumor; Drug-Related Side Effects and Adverse Reactions; Humans; Lichens; Liver Neoplasms; Male; Mice; Mice, Inbred Strains; Neoplasms, Experimental; Pulmonary Fibrosis; Smad Proteins

Mnk kinase is required for the phosphorylation and activation of the eukaryotic initiation factor 4E (eIF4E), which regulates translation of proteins involve in important aspects of hepatocellular carcinoma (HCC). Here we investigated whether an antifungal agent, cercosporamide, which had been recently identified as a potent Mnk inhibitor, is active against HCC and angiogenesis. We showed that cercosporamide significantly inhibited growth and induced caspase-dependent apoptosis on numerous HCC cell lines, while sparing normal liver cells. In addition, cercosporamide impaired HCC angiogenesis via inhibiting HCC-endothelial cells (HCC-EC) capillary network formation, migration, proliferation and survival. Importantly, cercosporamide sensitized HCC cells to cisplatin in in vitro cell culture and in vivo HCC xenograft mouse model. Cercosporamide blocked the phosphorylation of eIF4E but not Erk or p38 in a dose- and time-dependent manner in HCC and HCC-EC cells, suggesting that suppression of eIF4E phosphorylation was the result of inhibition of Mnk but not Mnk upstream pathways. Overexpression of constitutively active eIF4E (S209D) but not the nonphosphorylatable eIF4E (S209A) abolished the inhibitory effects of cercosporamide in HepG2 cells. Altogether, our work demonstrates that cercosporamide acts as a Mnk inhibitor through blockage of eIF4E phosphorylation and selectively exhibits anti-HCC activities. Our work suggests that targeting MNK-eIF4E pathway represents a therapeutic strategy to overcome chemo-resistance for HCC treatment.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Benzofurans; Carcinoma, Hepatocellular; Cell Proliferation; Cell Survival; Cisplatin; Dose-Response Relationship, Drug; Drug Synergism; Eukaryotic Initiation Factor-4E; Hep G2 Cells; Humans; Intracellular Signaling Peptides and Proteins; Liver Neoplasms; Mice, SCID; Neovascularization, Pathologic; Phosphorylation; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Signal Transduction; Time Factors; Transfection; Xenograft Model Antitumor Assays

Chinese medicines are emerging as an attractive new generation of anticancer drugs. Here, we explored the impact of salvianolic acid B (Sal B), the major water-soluble compounds of Danshen, on apoptosis and autophagy of human hepatocellular carcinoma cells (HCC). We also investigated the related molecular mechanisms. We found that Sal B exhibits potent ability to inhibit HCC cells viability in a concentration-dependent manner, and to induce apoptosis via the mitochondrial apoptosis pathway. Additionally, Sal B could also induce autophagy. Furthermore, pretreatment with the autophagy inhibitor chloroquine or 3-methyladenine showed the potential in attenuating the apoptosis rate induced by Sal B. Mechanistically, Sal B treatment inhibited the AKT/mTOR signaling cascade in vitro. Overexpression of AKT abolished the effects of Sal B on HCC cells, suggesting a critical role of the AKT/mTOR signaling pathway in Sal B-induced biological effects. Our results indicated that the mitochondrial pathway was involved in Sal B-induced apoptosis of HCC cells. Moreover, the AKT/mTOR signaling pathway was involved in Sal B-induced autophagy, which promoted apoptosis. This study may provide a promising strategy for using Sal B as a chemotherapeutic agent for patients with HCC.

Topics: Adenine; Antineoplastic Agents; Apoptosis; Autophagy; Beclin-1; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Chloroquine; Drugs, Chinese Herbal; Humans; Liver Neoplasms; Mitochondria; Proto-Oncogene Proteins c-akt; RNA Interference; RNA, Small Interfering; Salvia miltiorrhiza; Signal Transduction; TOR Serine-Threonine Kinases

Dieckol (DEK) is a naturally occuring phlorotannins found in marine brown algae Ecklonia cava which is attributed with various pharmacological properties. This study was aimed to investigate the protective role of DEK on N-Nitrosdiethylamine (NDEA) induced rat hepatocarcinogenesis. In this investigation 0.01% NDEA in drinking water for 15 weeks to induce hepatocellular carcinoma (HCC). DEK was administered orally (10, 20 and 40mg/kg body weight) for 15 weeks with 0.01% NDEA through drinking water. Hepatocarcinogesis was measured by the increased activities of serum liver marker enzymes namely aspartate trasaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), lactate dehydrogenase (LDH), α-fetoprotein (AFP) and total bilirubin along with increased elevation of cytochrome p450, lipid peroxidation markers, thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (HP), protein carbonyl content (PCC) and conjugated dienes (CD). The effect of NDEA was indicated by significant decreased activities of enzymatic antioxidants like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR) and non-enzymatic antioxidants like reduced glutathione, vitamin C and vitamin E. The oral administration of DEK at a dose of 40mg/kg body weight significantly reversed the activities of hepatic marker enzymes, dercreased lipid peroxidative markers, increased antioxidant cascade and decreased NDEA concentration in liver. DEK at a dose of 40mg/kg body weight was highly effective when compared to other two doses (10 and 20mg/kg body weight). All these changes were accompanied by histopathological observations in liver. The obtained results clearly demonstrated that DEK prevents lipid peroxidation, hepatic cell damage and promote the enzymatic and non-enzymatic antioxidant defense system in NDEA-induced hepatocarcinogenesis which might be due to activities like scavenging of oxy radicals by Dieckol.

Topics: Animals; Anticarcinogenic Agents; Antioxidants; Benzofurans; Biomarkers; Carcinoma, Hepatocellular; Cell Transformation, Neoplastic; Diethylnitrosamine; Lipid Peroxidation; Liver; Liver Function Tests; Liver Neoplasms, Experimental; Male; Oxidative Stress; Protein Carbonylation; Rats, Wistar

The enhancement of apoptosis is a therapeutic strategy used in the treatment of cancer. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising antitumor agent. However, hepatocellular carcinoma (HCC) cells exhibit marked resistance to the induction of cell death by TRAIL. The present study investigated whether rocaglamide, a naturally occurring product isolated from the genus Aglaia, is able to sensitize resistant HCC cells to TRAIL-mediated apoptosis. Two HCC cell lines, HepG2 and Huh-7, were treated with rocaglamide and/or TRAIL and the induction of apoptosis and effects on the TRAIL signaling pathway were investigated. The in vivo efficacy of rocaglamide was determined in TRAIL-resistant Huh-7-derived tumor xenografts. Rocaglamide significantly sensitized the TRAIL-resistant HCC cells to apoptosis by TRAIL, which resulted from the rocaglamide-mediated downregulation of cellular FLICE-like inhibitory protein and subsequent caspase-8 activation. Furthermore, rocaglamide markedly inhibited tumor growth from Huh-7 cells propagated in severe combined immunodeficient mice, suggesting that chemosentization also occurred in vivo. These data suggest that rocaglamide acted synergistically with TRAIL against the TRAIL-resistant HCC cells. Thus, it is concluded that rocaglamide as an adjuvant to TRAIL-based therapy may present a promising therapeutic approach for the treatment of HCC.

Topics: Animals; Apoptosis; Benzofurans; Carcinoma, Hepatocellular; CASP8 and FADD-Like Apoptosis Regulating Protein; Caspase 8; Cell Line, Tumor; Disease Models, Animal; Down-Regulation; Drug Resistance, Neoplasm; Drug Synergism; Female; Gene Knockdown Techniques; Hep G2 Cells; Humans; Liver Neoplasms; Mice; Mice, SCID; TNF-Related Apoptosis-Inducing Ligand

Anigopreissin A belongs to stilbene di- and oligomeric forms containing a benzofuran ring system whose biological activity is unknown. Recently, a completely protected Anigopreissin A - Permethylated Anigopreissin A - has been synthesized. We use MTT bioassay to assess Permethylated Anigopreissin A cytotoxicity in different human cell lines. Furthermore, fluorescence microscopy, caspase activity, real-time PCR and Western-blot methods are employed to evaluate apoptotic cell death pathway in liver cancer cells. Permethylated Anigopreissin A kills different types of human cancer cells but does not affect non-tumorigenic cells. The Permethylated Anigopreissin A concentration that causes 50% inhibition of liver tumor cells is 0.24μM. Hepatoma cells treated with Permethylated Anigopreissin A arrest their cell cycle in G1 phase. We also demonstrate that Permethylated Anigopreissin A-triggered cell death occurs by apoptosis. Decrease of the BCL2 expression levels, loss of the mitochondrial membrane potential, release of cytochrome c and increase of caspase 9 activity highlight a key role for mitochondria in Permethylated Anigopreissin A-induced apoptosis. Our study shows that Permethylated Anigopreissin A kills liver cancer cells through intrinsic apoptotic pathway.

Topics: Apoptosis; Benzofurans; Blotting, Western; Carcinoma, Hepatocellular; Cell Cycle; Cell Proliferation; Hep G2 Cells; Humans; Liver Neoplasms; Membrane Potential, Mitochondrial; Methylation; Real-Time Polymerase Chain Reaction; Stilbenes

Dibenzofuran is a direct precursor of extremely toxic compounds such as dioxins. It is widely distributed persistent organic pollutant in environment that potentiate oxidative stress, apoptosis, and necrosis through bioactivation in HepG2 cells. An alkalotolerent Pseudomonas strain ISTDF1 can metabolize dibenzofuran as a sole source of carbon and energy through diverse dioxygenation. However, there is a paucity of information about the potential toxic effects of the intermediary metabolites that are formed during treatment with dibenzofuran. We have assessed and discovered the potential mechanism of toxicity induced by metabolites of dibenzofuran that were formed at 18 and 36 h. Cell viability, CYP1A2 induction, ROS activity, Superoxide production, mitochondrial NADPH oxidase activity, and mitochondrial trans-membrane potential were studied using different assays such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), confocal laser scanning microscopy, and flow cytometry. Analysis revealed formation of 2-(1-carbonyl methylidine)-2,3-dihydrobenzofuranlidene after 18 h of bacterial treatment due to oxygenation at carbon (C3-C4). This compound induces higher mitochondrial NADPH oxidase-dependent superoxide production that makes it more toxic than the parent compound. It was evident that after 36 h of bacterial treatment, toxicity induced by dibenzofuran and its metabolites was completely removed. This study highlights the fact that despite of efficient biodegradation of toxicants, bioactive toxic intermediates can be formed. Therefore, it is necessary to assess the toxicity of each intermediary for complete mitigation of associated risk.

Topics: Benzofurans; Biodegradation, Environmental; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Survival; Cytochrome P-450 CYP1A2; Hep G2 Cells; Humans; Membrane Potential, Mitochondrial; Mitochondria, Liver; NADPH Oxidases; Pseudomonas; Reactive Oxygen Species; Superoxides

Condensed-bicyclic triazolo-thiadiazoles were synthesized via an efficient "green" catalyst strategy and identified as effective inhibitors of PTP1B in vitro. The lead compound, 6-(2-benzylphenyl)-3-phenyl-[1,2,4]triazolo[3][1,3,4]thiadiazole (BPTT) was most effective against human hepatoma cells, inhibits cell invasion, and decreases neovasculature in HUVEC and also tumor volume in EAT mouse models. This report describes an experimentally unidentified class of condensed-bicyclic triazolo-thiadiazoles targeting PTP1B and its analogs could be the therapeutic drug-seeds.

Topics: Animals; Antineoplastic Agents; Benzofurans; Carcinoma, Ehrlich Tumor; Carcinoma, Hepatocellular; Caspase 3; Cell Line, Tumor; Cell Movement; Chromones; Cyclin D1; Disease Models, Animal; Dose-Response Relationship, Drug; Female; G1 Phase Cell Cycle Checkpoints; Hep G2 Cells; Human Umbilical Vein Endothelial Cells; Humans; Inhibitor of Apoptosis Proteins; Liver Neoplasms; Mice; Models, Molecular; Neoplasm Invasiveness; Neovascularization, Pathologic; Poly(ADP-ribose) Polymerases; Protein Tyrosine Phosphatase, Non-Receptor Type 1; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; STAT3 Transcription Factor; Structure-Activity Relationship; Survivin; Thiadiazoles; Triazoles

Sedanolide (SN), a phthalide-like compound from celery seed oil, possesses antioxidant effects. However, the effect of SN on cell death in human liver cancer cells has yet to be determined. In this study, cell viability determination, monodansylcadaverine (MDC) fluorescent staining and immunoblot analysis were performed to determine autophagy induction and autophagy-induced protein expression changes via molecular examination after human liver cancer (J5) cells were treated with SN. Our studies demonstrate that SN suppressed J5 cell viability by inducing autophagy. Phosphoinositide 3-kinase (PI3K)-I, mammalian target of rapamycin (mTOR) and Akt protein levels decreased, whereas PI3K-III, LC3-II and Beclin-1 protein levels increased following SN treatment in J5 cells. In addition, SN treatment upregulated nuclear p53 and damage-regulated autophagy modulator (DRAM) and downregulated cytosolic p53 and Tp53-induced glycolysis and apoptosis regulator (TIGAR) expression in J5 cells. Furthermore, the cytosolic phosphorylation of inhibitor of kappa B (IκB) and nuclear p65 and the DNA-binding activity of NF-κB increased after SN treatment. These results suggest that SN induces J5 cell autophagy by regulating PI3K, p53 and NF-κB autophagy-associated signaling pathways in J5 cells.

Topics: Antineoplastic Agents; Autophagy; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Survival; Humans; Immunoblotting; Liver Neoplasms; NF-kappa B; Phosphatidylinositol 3-Kinases; Signal Transduction; Tumor Suppressor Protein p53

A series of butylphthalide derivatives (BPDs) 1-8 were isolated from the extract of the dried rhizome of Ligusticum chuanxiong Hort. (Umbelliferae). The cytotoxic activities of BPDs 1-8 were evaluated using a panel of human cancer cell lines. In addition, the SAR analysis and potential anti-invasion activities were investigated. The sp² carbons at C-7 and C-7a appeared to be essential for the cytotoxic activities of BPDs. BPDs 5 and 6 remarkably inhibited the migration and invasion of cancer cells. The anti-invasion activity of dimer 6 was demonstrated to be significantly higher than monomer 5.

Topics: Antineoplastic Agents; Benzofurans; Carcinoma, Hepatocellular; Cell Adhesion; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Humans; Inhibitory Concentration 50; Liver Neoplasms; Molecular Structure; Plant Extracts

Hepatocellular carcinoma is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. The efficacy of novel combination treatments are increasingly evaluated with use of integrative biology research and development (R&D) strategies and methodological triangulation. We investigated the anti-tumor effect of ɛ-viniferin alone, and the putative synergy of ɛ-viniferin with vincristine on the growth of HepG2 cells in vitro. Growth inhibition and apoptosis induction were determined by MTT assay and annexin V/propidium iodide (PI), respectively. Morphological changes and DNA fragmentation were investigated under electron microscopy and by agarose gel electrophoresis, respectively. The results collectively showed that treating cells with ɛ-viniferin and vincristine significantly inhibited cell viability at lower doses as compared to each agent applied alone. IC(50) values for ɛ-viniferin and vincristine were determined as 98.3 and 52.5 μM at 24 h, respectively. IC(50) value of ɛ-viniferin in combination with vincristine was 15.8+11.25 μM (mean/SD) at 24 h. The viability of cells treated with 17.9 μM vincristine alone for 24 h was 79.62%; it reduced to 26.53% when 25 μM ɛ-viniferin was added in combination with vincristine (p<0.05). We found that combination of drugs promoted the sensitivity of cells against to vincristine treatment. The effect of combined use was in support of a synergistic pharmacodynamic effect. Moreover, low doses of the combination regimen induced phosphatidyl re-localization, morphological changes, and DNA fragmentation, and therefore caused apoptotic death. This study thus suggests that low concentrations of ɛ-viniferin and vincristine can enhance the anti-tumor effects efficiently by inducing HepG2 cell apoptosis. Further studies in other model systems are warranted with a view to potential future applications in the clinic of such combination regimens and their putative mechanism of action in the observed synergy reported here.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Benzofurans; Carcinoma, Hepatocellular; Cell Shape; Cell Survival; DNA Fragmentation; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Drug Synergism; Hep G2 Cells; Humans; Inhibitory Concentration 50; Liver Neoplasms; Stilbenes; Vincristine

Iron accumulation and iron-related oxidative stress are involved in several pathological conditions and provide a rationale for the development of iron chelators as novel promising therapeutic strategies. Thus, we have recently synthesized multifunctional non-toxic, brain permeable iron chelating compounds, M30 and HLA20, possessing the neuroprotective N-propargyl moiety of the anti-Parkinsonian drug, monoamine oxidase (MAO)-B inhibitor, rasagiline and the antioxidant-iron chelating moiety of an 8-hydroxyquinoline derivative of the iron chelator, VK28. Here, we examined the hepatic regulatory effects of these novel compounds using two experimental approaches: chelation activity and glucose metabolism parameters. The present study demonstrated that M30 and HLA20 significantly decreased intracellular iron content and reduced ferritin expression levels in iron-loaded hepatoma Hep3B cells. In electron microscopy analysis, M30 was shown to reduce the electron-dense deposits of siderosomes by ~30 %, as well as down-regulate cytosolic ferritin particles observed in iron-overloaded cells. In vivo studies demonstrated that M30 administration (1 mg/kg, P.O. three times a week) reduced hepatic ferritin levels; increased hepatic insulin receptor and glucose transporter-1 levels and improved glucose tolerance in C57BL/6 mice and in a mouse model of type-2 diabetes, the ob/ob (leptin(-/-)). The results clearly indicate that the novel multifunctional drugs, especially M30, display significant capacity of chelating intracellular iron and regulating glucose metabolism parameters. Such effects can have therapeutic significance in conditions with abnormal local or systemic iron metabolism, including neurological diseases.

Topics: Animals; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Dose-Response Relationship, Drug; Ferric Compounds; Ferritins; Glucose; Glucose Tolerance Test; Humans; Hydroxyquinolines; Iron; Iron Chelating Agents; Leptin; Liver; Male; Mice; Mice, Transgenic; Microscopy, Electron, Transmission; Monoamine Oxidase Inhibitors; Neuroprotective Agents; Piperazines; Quaternary Ammonium Compounds; Quinolines

Phlorotannins have been reported to demonstrate several biological properties, including antioxidant activity, and activities useful in the treatment of diabetic complications and in chemoprevention of several vascular diseases. In this study, we focused on the apoptosis induced by dieckol, a marine algal phlorotannin isolated from Ecklonia stolonifera, on human hepatocellular carcinoma (HCC) Hep3B cells. Dieckol reduced the numbers of viable cells and increased the numbers of apoptotic cells in a dose-dependent manner. Immunoblotting analysis revealed that dieckol increased the expression levels of cleaved caspases-3, 7, 8, and 9, and cleaved poly(ADP-ribose) polymerase. Dieckol increased the permeability of mitochondrial membranes and the release of cytochrome c from mitochondria into the cytosol with apoptosis-inducing factor. In addition, dieckol induced increased expression of truncated Bid and Bim. The results indicate that dieckol induces apoptosis via the activation of both death receptor and mitochondrial-dependent pathways in HCC Hep3B cells.

Topics: Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Bcl-2-Like Protein 11; Benzofurans; BH3 Interacting Domain Death Agonist Protein; Carcinoma, Hepatocellular; Caspases; Cell Line, Tumor; Cell Survival; Cytochromes c; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; HEK293 Cells; Humans; Liver Neoplasms; Membrane Proteins; Mitochondrial Membranes; Permeability; Phaeophyceae; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins

Hepatocellular carcinoma (HCC) is one of the most common malignancies, yet there have been no significant advances in effective therapeutics. In this study, HS-111 was synthesized as a novel thiazolamine derivative, N-(5-(2-chlorobenzyl) thiazole-2-yl) benzofuran-2-carboxamide, and its anticancer effect and mechanism were examined in human HCC cells. HS-111 strongly suppressed the growth of HCC cells in a dose-dependent manner. Also, apoptosis by HS-111 was identified by DAPI and TUNEL staining, and the increases of the cleaved caspase-3 were observed. In addition, HS-111 decreased protein expression of hypoxia-inducible factor (HIF-1α) and secretion of vascular endothelial growth factor (VEGF), and inhibited tube formation and the migration of human umbilical vein endothelial cells (HUVECs). These results showed that HS-111 not only inhibited cell growth and angiogenesis, but also induced apoptosis of human HCC cells. We suggest that HS-111 may be a potential candidate for chemotherapy against HCC.

Topics: Angiogenesis Inhibitors; Apoptosis; Benzofurans; Blotting, Western; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Human Umbilical Vein Endothelial Cells; Humans; In Situ Nick-End Labeling; Liver Neoplasms; Molecular Structure; Neovascularization, Pathologic; Thiazoles; Wound Healing

The chemical investigation of the twigs of Morus mesozygia resulted in the isolation of three new prenylated 2-arylbenzofurans, named moracin KM, LM, and SC (1-3), nine known 2-arylbenzofurans (4-12), and two known flavonoids (13-14). The structures of the new compounds were established as [2'',3'':6,7]-(6-(S)-hydroxymethyl-6-methylpyrano)-2-(3,5-dihydroxyphenyl)benzofuran-5-ol (1), [2'',3'':6,7]-(4,7-dihydro-6-methyloxepine)-2-(3-hydroxy-5-methoxyphenyl)benzofuran-5-ol (2), and [2'',3'':6,7]-(6,6-dimethylpyrano)-2-(3,5-dihydroxyphenyl)benzofuran (3). One of the new compounds, moracin LM (2), displayed modest antioxidant activity, whereas known compounds 4, 13, and 14 showed significant hepatoprotective and antioxidant activities.

Topics: Animals; Antioxidants; Benzofurans; beta Carotene; Carcinoma, Hepatocellular; Cell Survival; Drug Evaluation, Preclinical; Flavonoids; Lipid Peroxidation; Liver Neoplasms; Magnetic Resonance Spectroscopy; Microsomes, Liver; Molecular Structure; Morus; Plant Extracts; Plants, Medicinal; Protective Agents; Rats; Spectrophotometry, Infrared

Coumarins are natural compounds found in many plants that possess medical value by itself and its modified derivatives.. Six novel coumarin derivatives were synthesized and examined for their potential anticancer cytotoxicity.. Among the 6 derivatives, 3,5-dimethyl-(7)H-furo[3,2-g]chromen-7-one (DMFC) presented the strongest cytotoxicity against human hepatoma HepG2 cells in vitro with an IC(50) value of 8.46 ± 0.28 μM in a 48-hour treatment. Further experiments revealed that DMFC induced apoptosis in HepG2 cells through both extrinsic and intrinsic apoptotic pathways in a p53-dependent manner. Mechanistically, DMFC activated caspases 3, 8 and 9, depolarized mitochondrial membrane potential and induced cytochrome c and apoptosis-inducing factor release. DMFC-induced apoptosis was also characterized by DNA fragmentation, phosphatidylserine externalization and sub-G1 peak in DNA histograms. Moreover, both caspase 8 and 9 inhibitors suppressed the apoptosis induced by DMFC. Western blot analyses revealed that DMFC also significantly increased the expression levels of p53, Fas death receptor, Fas-associated death domain protein and proapoptotic Bcl-2 family members such as Bax, Bad and tBid, as well as decreased the levels of pro-survival members such as Bcl-2 and Bcl-xl.. DMFC is potentially an effective therapeutic agent in liver cancer therapy.

Topics: Antineoplastic Agents; Apoptosis; Apoptosis Inducing Factor; bcl-X Protein; Benzofurans; Carcinoma, Hepatocellular; Caspases; Coumarins; Cytochromes c; DNA Fragmentation; fas Receptor; Hep G2 Cells; Humans; Liver Neoplasms; Membrane Potential, Mitochondrial; Phosphatidylserines; Proto-Oncogene Proteins c-bcl-2; Tumor Suppressor Protein p53

Hepatocellular carcinoma (HCC) is one of the most common malignancies, yet there have been no significant advances in effective therapeutics. In this study, HS-113 was synthesized as a novel compound, N-(5-(2-bromobenzyl) thiazole-2-yl) benzofuran-2-carboxamide and its cytotoxic activity and anti-cancer effect were examined in human HCC cells. HS-113 strongly suppressed growth of HCC cells in a dose-dependent manner, induced apoptosis by increasing the proportion of sub-G1 apoptotic cells, and caused cell cycle arrest at G0/G1 phase. Also, HS-113 increased the expression of p27 and decreased that of cyclin D1 associated with cell cycle arrest. Apoptosis by HS-113 was confirmed by DAPI and TUNEL staining, and the increases of the cleaved PARP and caspase-3 were observed. Furthermore, HS-113 decreased protein expression of HIF-1α and secretion of VEGF, and inhibited the tube formation of HUVECs. These results showed that HS-113 not only inhibited cell growth and angiogenesis, but also induced apoptosis of human HCC cells. We suggest that HS-113 may be a potential candidate for cancer therapy against HCC.

Topics: Antineoplastic Agents; Apoptosis; Benzofurans; Blotting, Western; Carcinoma, Hepatocellular; Cell Cycle; Cell Cycle Proteins; Cell Proliferation; Cells, Cultured; Endothelium, Vascular; Enzyme-Linked Immunosorbent Assay; Humans; Liver Neoplasms; Neovascularization, Pathologic; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins c-bcl-2; Thiazoles; Umbilical Veins

In this study, we assessed the antitumor activity of the methanol extract from wood chips of the heartwood of the Taiwan red cypress, Chamaecyparis formosensis Matsumura, which is a precious tree species endemic to Taiwan. A brine shrimp lethality test (BST) indicated that the ethyl acetate (EtOAc)-soluble extract from the MeOH extract was a suitable candidate (LC (50) = 15.36 microg/mL) for further studies of the antitumor activity of its components. From this EtOAc fraction, we isolated six lignans and two norlignans and tested their cytotoxic activities IN VITRO against promyelocytic leukemia (HL-60) and hepatoma (Hepa-G2) cell lines. Among these compounds, 7,7'-( S)-dihydrotaiwanin C, isolated for the first time from nature, with its single crystal structure depicted in this study, exhibited significant cytotoxic activity against HL-60 cell lines IN VITRO (IC (50) = 4.03 microg/mL) after 24 hours. BST:brine shrimp lethality test Hepa-G2:human hepatoma HL-60:human leukemia IC (50):half-maximal inhibitory concentration SARs:structure-activity relationships AS:adenine sulfate.

Topics: Animals; Antineoplastic Agents, Phytogenic; Artemia; Benzodioxoles; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Chamaecyparis; Chromatography, High Pressure Liquid; Cytotoxins; Drug Screening Assays, Antitumor; HL-60 Cells; Humans; Lignin; Plant Extracts; Structure-Activity Relationship; Wood

Animal bedding made of waste wood samples from seven different plants in Japan were chemically analyzed in terms of persistent organic pollutants (POPs) including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs), coplanar polychlorinated biphenyls (Co-PCBs), drin compounds, chlordane compounds and various inorganic toxic compounds (Cr, Cu, As, B, Cd and Pb) to investigate the chemical characteristics and levels of contamination. Further investigation was conducted to determine the success of applying the Chemically Activated Luciferase Expression (CALUX) bioassay to the waste wood samples in combination with a cleanup procedure for the detection of dioxin-like compounds in order to develop the CALUX bioassay as a rapid and cost-effective screening/monitoring method and a contributive tool to risk management in the waste wood recycling process. For the cleanup procedure, crude extracts from wood samples were prepared by dimethylsulfoxide (DMSO)/n-hexane extraction, and then the extracts were processed by silica gel-44% sulfuric acid reflux treatment at 70 degrees C for 60 min to yield the bioassay fractions. The presence of POPs and inorganic toxic compounds were confirmed in most of the litter samples. In particular, Co-PCBs in one sample (litter dust) showed a high concentration level (1200000 pg/g, 240 pg TEQ/g), suggesting the potential for contamination from demolition waste. The CALUX assay-determined TEQs (CALUX-TEQs) were significantly high in the sample after DMSO/n-hexane extraction, probably due to labile aryl hydrocarbon receptor (AhR) ligands such as PAHs; however, they were remarkably reduced through a single silica gel-44% sulfuric acid reflux treatment. The ratio between CALUX-TEQ values and WHO toxicity equivalent values (WHO-TEQ) obtained by congener-specific chemical analysis ranged from 0.058 to 22 and show comparatively good agreement. Underestimation in some samples, however, was observed where WHO-TEQ values of Co-PCBs contributed greatly to total WHO-TEQ values. Reasons for this gap could be lower CALUX assay-determined relative potencies (REPs) than the WHO-TEFs for these congeners or AhR-antagonistic effects of non dioxin-like PCBs which coexist at higher concentration than Co-PCBs. The CALUX assay is proposed as a promising application in the recycling process of wooden materials.

Topics: Animals; Benzofurans; Biological Assay; Carcinoma, Hepatocellular; Conservation of Natural Resources; Dibenzofurans, Polychlorinated; Environmental Monitoring; Environmental Pollutants; Housing, Animal; Japan; Liver Neoplasms; Luciferases; Polychlorinated Biphenyls; Polychlorinated Dibenzodioxins; Rats; Soil Pollutants; Tumor Cells, Cultured; Wood

1: The metabolism by HepG2 cell from two sources (M1, M2) of 12 substrates is reported: ethoxyresorufin, ethoxycoumarin, testosterone, tolbutamide, chlorzoxazone, dextromethorphan, phenacetin, midazolam, acetaminophen, hydroxycoumarin, p-nitrophenol and 1-chloro-2,4-dinitrobenzene (CDNB), and a pharmaceutical compound, EMD68843. 2: Activities varied markedly. Some were present in M1 (CYP1A, CYP2C9, CYP2E1) but absent in M2. M1 had a more complete set of Phase I enzymes than M2. CYP1A2, CYP2C9, CYP2D6, CYP2E1 and CYP3A activities were present at levels similar to human hepatocytes. Phase II metabolism differed between M1 and M2. M1 conjugated hydroxycoumarin and p-nitrophenol to glucuronides only, whereas M2 produced sulfates. Glutathione conjugation of CDNB metabolism was 10-fold higher in M1 than in M2, but was still much lower than in human hepatocytes. CYP2E, CYP2C, CYP2B6 and CYP3A (but not CYP1A, glucuronyl S-transferase or S-transferase) were inducible in M1. Metabolites of EMD68843, produced by induced (but not uninduced) M1 were the same as those produced in human hepatocytes. 3: In conclusion, HepG2 cells have both Phase I and II enzymes, which activities and at what levels depend on the source and culture conditions. Therefore, HepG2 cells routinely used in in vitro assays should be characterized for their drug-metabolizing capabilities before any results can be fully interpreted.

Topics: Aryl Hydrocarbon Hydroxylases; Benzofurans; Carcinoma, Hepatocellular; Cell Culture Techniques; Cell Line, Tumor; Coumarins; Dinitrochlorobenzene; Enzyme Activation; Humans; Indoles; Kinetics; Liver Neoplasms; Nitrophenols; Oxazines; Piperazines; Substrate Specificity; Umbelliferones; Vilazodone Hydrochloride

Regulation of gene expression by the aryl hydrocarbon (AHR) receptor is a much-studied pathway of molecular toxicology. Activation of AHR by the xenobiotic ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is hypothesized as the mechanism by which TCDD exerts its toxic and carcinogenic effects. Paradoxically, some studies have shown that TCDD acts as an antiestrogen. This has led to the hypothesis that so-called selective aryl hydrocarbon receptor modulators (SAhRMs), AHR ligands that retain the antiestrogenic effects but lack the transcriptional effects of TCDD associated with toxicity, may be utilized as cancer chemotherapeutics in conjunction with other antiestrogenic compounds such as tamoxifen. The present study attempts to further define the molecular mechanism of action of the putative SAhRMs, 6-alkyl-1,3,8-trichlorodibenzofuran (6-MCDF), and diindolylmethane (DIM), focusing particularly on the former. We tested 6-MCDF and DIM for the recruitment of AHR and RNA polymerase II (pol II) to the regulatory region of the AHR responsive gene, cytochrome P4501A1 (CYP1A1), using the chromatin immunoprecipitation (ChIP) assay in the mouse hepatoma cell line Hepa-1c1c7 (Hepa-1). We also tested the level of CYP1A1 induction in Hepa-1 cells using quantitative real-time PCR. We show no difference in the recruitment of AHR or pol II to the regulatory region of CYP1A1 in response to TCDD, 6-MCDF, or co-treatment with both TCDD and 6-MCDF. Our results also show no antagonism of CYP1A1 induction with co-treatment of Hepa-1 cells with TCDD and 6-MCDF. These data suggest that 6-MCDF exhibits agonist activity with respect to induction of CYP1A1 in the Hepa-1 cell line.

Topics: Animals; Benzofurans; Carcinoma, Hepatocellular; Cell Line, Tumor; Cytochrome P-450 CYP1A1; Liver Neoplasms; Mice; Polychlorinated Dibenzodioxins; Receptors, Aryl Hydrocarbon; RNA, Messenger

Multivariate models are reported that can predict the relative toxicity of compounds with severe environmental impact, namely polychloro dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Multiple linear regression analysis (MLR) and partial least square projections of latent variables (PLS) show the usefulness of graph-theoretical descriptors, mainly topological charge indices (TCIs), in these series. The general trends of the group are correctly reproduced and better results are presented than have previously been published. In general, the more toxic compounds exhibit more symmetric molecular structures.

Topics: Animals; Benzofurans; Carcinoma, Hepatocellular; Cytochrome P-450 CYP1A1; Dioxins; Disease Models, Animal; Drug Design; Environmental Pollutants; Least-Squares Analysis; Linear Models; Models, Chemical; Models, Statistical; Models, Theoretical; Multivariate Analysis; Neoplasms, Experimental; Polychlorinated Dibenzodioxins; Quantitative Structure-Activity Relationship; Rats; Reproducibility of Results; Soil Pollutants

Topics: Animals; Benzofurans; Biological Assay; Carcinoma, Hepatocellular; Carps; Cytochrome P-450 CYP1A1; Environmental Exposure; Liver; Liver Neoplasms; Polychlorinated Dibenzodioxins; Rats

Stimulatory effects of a novel isobenzofranone, MD-700, on low density lipoprotein (LDL) receptor activity were investigated in vitro and in vivo. MD-700 at 0.03 microg/ml elevated the expression of LDL receptor in HepG2 cells within 4 h. Corresponding to this, uptake of fluorescent labeled-LDL (3,3'-dioctadecylindocarbocyanine-LDL) by the cells increased linearly in time- and dose-dependent manner by MD-700 for up to 12 h. In the experiment using HepG2 cells transiently transfected with promoter-luciferase gene constructs, MD-700 increased luciferase activity in a dose-dependent manner from 0.03 to 0.1 microg/ml. In contrast, luciferase activity was not stimulated by MD-700 in construct with a deleted sterol regulatory element (SRE)-1, suggesting importance of SRE-1 in stimulation of the LDL receptor gene promoter by MD-700. Binding experiments on liver membranes from MD-700-treated hamsters showed about a 60% increase in 125I-labeled LDL binding. A Scatchard plot revealed that MD-700 increased the maximal binding without affecting binding affinity. In contrast to findings with an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, pravastatin, MD-700 had no effect on the sterol synthesis in hamster liver homogenates. These results suggest that MD-700 stimulates the expression of LDL receptor, presumably in a manner independent of change in sterol metabolism, and thereby promotes LDL clearance. Hypocholesterolemic actions of MD-700 in hamsters were then examined. MD-700 lowered serum cholesterol levels in hamsters fed normal chow or a high-fat diet. Fractionation of serum lipoproteins demonstrated that MD-700 selectively decreased LDL and very low density lipoprotein cholesterol. Dose-dependent decrease in serum cholesterol was also seen in hypercholesterolemic rats. Thus, the hypocholesterolemic action of MD-700 may be attributed to up-regulation of the LDL receptor, based on stimulation of the transcription of the LDL receptor gene. Although pravastatin stimulates LDL uptake and lowers serum cholesterol in a manner similar to that seen with MD-700, the mechanism responsible for hypocholesterolemic action appears to differ.

Topics: Animals; Benzofurans; Blotting, Northern; Carbocyanines; Carcinoma, Hepatocellular; Cell Membrane; Cholesterol; Cricetinae; Disease Models, Animal; DNA Primers; Fluorescent Dyes; Humans; Hypercholesterolemia; Lipoproteins, LDL; Lipoproteins, VLDL; Liver Neoplasms; Male; Promoter Regions, Genetic; Rats; Rats, Wistar; Receptors, LDL; RNA, Messenger; RNA, Neoplasm; Sterols; Transcription, Genetic; Tumor Cells, Cultured; Up-Regulation

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), 2,3,7,8-tetrachlorodibenzofuran (TCDF), and benz[a]anthracene (BA) highly induce cytochrome P4501A1, determined by aryl hydrocarbon hydroxylase (AHH) activity, in human hepatoma HepG2 cells within 24 h. AHH activity induced by TCDD and TCDF persists for at least 48 h. In contrast, AHH activity induced by BA rapidly declines, although the amounts applied are 4-5 orders of magnitude higher than those of TCDD or TCDF. AHH induction in HepG2 cells differs from that in rat hepatoma cells H4IIEC3/T in two aspects: (1) HepG2 cells are 20 times less sensitive to the test compounds than H4IIEC3/T cells. (2) TCDF-induced AHH activity does not persist in the rat cells. The results suggest that human HepG2 cells, because of their low sensitivity, are inferior to rat H4IIEC3/T cells for determining TCDD equivalents in environmental samples. They may be useful for investigating species dependent differences in the toxicokinetics of individual polyhalogenated aromatic hydrocarbon congeners.

Topics: Animals; Aryl Hydrocarbon Hydroxylases; Benz(a)Anthracenes; Benzofurans; Biological Assay; Carcinoma, Hepatocellular; Cytochrome P-450 CYP1A1; Environmental Pollutants; Humans; Liver Neoplasms; Polychlorinated Dibenzodioxins; Rats; Tumor Cells, Cultured

Conditions have been established for H4IIE rat hepatoma cell cultures in which effects of cytochrome P-450 induction on the metabolism of a munitions wastestream pollutant can be studied. Under these conditions, the polychlorinated hydrocarbon 2,3,4,7,8-pentachlorodibenzfuran (PCDBF) induced cytochrome P-450 (1A1) aryl hydrocarbon hydroxylase (AHH) activity over a wide range of concentrations without significant cytotoxic effects. The munition pollutant 2,4-dinitrotoluene (2,4-DNT) did not induce AHH activity itself, but its metabolism was considerably altered when applied to PCDBF induced cultures. Production of amino nitrotoluene isomers was greatly enhanced in induced cultures as compared to uninduced controls, as was the conversion of radiolabeled 2,4-DNT to relatively more polar metabolites. To some extent, the results with H4IIE cells parallel those reported for animals exposed to 2,4-DNT after induction of cytochrome P-450 AHH activity. The preliminary findings suggest that with further development and validation, H4IIE cultures could be of use in characterizing metabolites that result from exposure to chemical mixtures involving a P-450 (1A1) inducer.

Topics: Animals; Aryl Hydrocarbon Hydroxylases; Benzofurans; Carcinoma, Hepatocellular; Cell Survival; Cytochrome P-450 Enzyme System; Dinitrobenzenes; Enzyme Induction; Liver Neoplasms; Luminescent Measurements; Mutagenicity Tests; Oxidation-Reduction; Rats; Spectrophotometry, Ultraviolet; Tumor Cells, Cultured

Fractions containing polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were extracted from river sediments by various extraction methods. The amount of individual pollutants was determined analytically and data compared with biological assays. These were based on the induction of cytochrome P450 1A1 (CYPIA1) after treatment with sediment fractions in two different biological model systems, a mouse hepatoma cell line Hepa-1 and a chick embryo. In the hepatoma cell culture Hepa-1 significant correlations with analytical results were found for fractions containing PCDD/Fs and planar and mono-ortho-chlorinated PCBs. However for PAH fraction an undesirable decrease of P450 1A1 induction was observed in higher concentrations of this fraction. This decrease was not observed in the chick embryo liver microsomes and biological responses towards the PAH fractions correlated with analytical data. Comparative investigations demonstrated that the chicken embryo hepatic microsomes were more sensitive for PAHs, and the hepatoma cell line Hepa-1 for PCDD/Fs and planar and mono-ortho-chlorinated PCBs.

Topics: Animals; Benzofurans; Biological Assay; Carcinoma, Hepatocellular; Chick Embryo; Cytochrome P-450 CYP1A1; Cytochrome P-450 Enzyme System; Dibenzofurans, Polychlorinated; Environmental Monitoring; Enzyme Induction; Fresh Water; Liver; Liver Neoplasms; Mice; Microsomes, Liver; Oxidoreductases; Polychlorinated Biphenyls; Polychlorinated Dibenzodioxins; Polycyclic Compounds; Sensitivity and Specificity; Tumor Cells, Cultured; Water Pollutants, Chemical

Antibiotic C3368-A (CA) is produced by a fungus strain from a soil sample collected in Antarctica. CA markedly inhibited radiolabeled thymidine and uridine transport in mouse Ehrlich carcinoma cells, its 50% inhibitory concentration (IC50) being 4.6 and 7.7 microM, respectively. In clonogenic assay, CA displayed a synergistic effect with methotrexate (MTX), mitomycin C (MMC), 5-fluorouracil (5FU), and Adriamycin (ADR) against human oral epidermoid carcinoma KB cells. CA also markedly enhanced the inhibitory effect of 5FU and ADR on the proliferation of human hepatoma BEL-7402 cells as determined by the p-nitrophenyl-N-acetyl-beta-D-glucosaminide (NAG) enzyme-reaction assay. 5FU or ADR cytotoxicity was not augmented by CA in human fetal lung 2BS cells. In vivo, CA significantly potentiated the inhibitory effect of MMC against colon carcinoma 26 in mice. No significant augmentation of toxicity by the combination was found in treated mice. The results suggest that CA, the newly found nucleoside-transport inhibitor, may be useful in potentiation of the effect of antitumor drugs.

Topics: Animals; Antibiotics, Antineoplastic; Antineoplastic Agents; Benzofurans; Biological Transport; Carcinoma, Ehrlich Tumor; Carcinoma, Hepatocellular; Cell Division; Colonic Neoplasms; Doxorubicin; Drug Synergism; Female; Fluorouracil; Humans; KB Cells; Liver Neoplasms; Methotrexate; Mice; Mice, Inbred BALB C; Mitomycin; Spiro Compounds; Thymidine; Tumor Cells, Cultured; Tumor Stem Cell Assay; Uridine

1. Our previous studies have shown that benzo(a)pyrene (BP), 3-methylcholanthrene (3MC) and tetrachlorodibenzofuran (TCDBF) can induce the expression of the cytochrome P450IA1 mRNA in the rat hepatoma cell line, H4IIE, although the kinetics of induction differed. 2. In the present study, by using biochemical, immunochemical and recombinant DNA approaches, the effects of these inducers have been examined on the steady state level of endogenous cytochrome P450IA1 protein and on induction of chloramphenicol acetyltransferase activity (CAT) in the H4IIE cells transfected with pMC1CAT (a recombinant construct consisting of CAT linked to 5' upstream DNA sequence of the rat cytochrome P450IA1 gene). 3. From 7-ethoxyresorufin O-deethylase activity (EROD) and immunochemical analysis of cytochrome P450IA1, the optimal concentrations of BP, 3MC and TCDBF for induction in the H4IIE cells were determined as 1, 0.1-1 and 0.1 microM, respectively. 4. The elevated expression of the protein was more sustained in the TCDBF-exposed cells than in the BP or 3MC-treated cells. 5. After 1.5 hr of treatment, little if any detectable P450IA1 protein was observed in the H4IIE cells although a considerable amount of mRNA was present. 6. In addition, no cytochrome P450IA2 protein was detected in the control or induced H4IIE cells. 7. H4IIE cells were transfected by pMC1CAT, and the induction ratio of CAT expression in the transfected H4IIE cells after BP, 3MC or TCDBF treatment was 10-, 17- and 40-fold, respectively. 8. These results indicate that the rat H4IIE cell line offers a valid homologous system for studies of the regulation of the rat cytochrome P450IA1 gene.

Topics: Animals; Benzo(a)pyrene; Benzofurans; Blotting, Western; Carcinoma, Hepatocellular; Chloramphenicol O-Acetyltransferase; Cytochrome P-450 CYP1A1; Cytochrome P-450 Enzyme System; Enzyme Induction; Gene Expression Regulation, Enzymologic; Kinetics; Methylcholanthrene; Oxidoreductases; Rats; Recombinant Proteins; RNA, Messenger; Transfection; Tumor Cells, Cultured

Aryl hydrocarbon hydroxylase (AHH)-inducing potency of eight polychlorinated dibenzofuran (PCDF) isomers, 3,4,5,3',4',5'-hexachlorobiphenyl (HCB) and 2,3,7,8-tetrachlorodibenzo-p-dioxon (TCDD) in two inbred mouse strains (AHH responsive and nonresponsive mouse strains) and eight human lymphoblastoid cell lines (four males and four females) was investigated to evaluate their relative toxic potency. In AHH nonresponsive DBA mouse strain, only TCDD induced hepatic AHH activity at a dose of 30 micrograms/kg, while in AHH responsive C57 mouse strain, six PCDF isomers besides TCDD could enhance the enzyme activity significantly. 2,3,7,8-Tetrachlorodibenzofuran (2,3,7,8-TCDF), 1,2,3,7,8-pentachlorodibenzofuran (1,2,3,7,8-PCDF) and 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PCDF) showed the highest AHH inducing activity among the PCDF isomers tested. In contrast with the results obtained from the mouse experiments, in human lymphoblastoid cells, 2,3,4,7,8-PCDF, 1,2,3,4,6,7-hexachlorodibenzofuran (1,2,3,4,6,7-HCDF) and 1,2,3,7,8-hexachlorodibenzofuran (1,2,3,4,7,8-HCDF) elicited the highest AHH induction and were as potent AHH inducers as TCDD. These observations suggest that toxicities of 2,3,4,7,8-PCDF, 1,2,3,4,6,7-HCDF and 1,2,3,4,7,8-HCDF in human tissues may be comparable to that of TCDD. It was also observed that in both male and female human cell lines, the degree of AHH inducibilities of these compounds were roughly parallel to that of 3-methylcholanthrene, possibly indicating that genetic susceptibility among human population to the toxic compounds are also present similar to those reported among mouse strains.

Topics: Animals; Aryl Hydrocarbon Hydroxylases; Benzofurans; Carcinoma, Hepatocellular; Cells, Cultured; Dibenzofurans, Polychlorinated; Dioxins; Enzyme Induction; Female; Humans; Isomerism; Liver; Liver Neoplasms; Lymphocytes; Male; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Polychlorinated Biphenyls; Polychlorinated Dibenzodioxins