oxadiazoles and Liver-Neoplasms

Fluoroquinolones are targets of interest due to their broad spectrum antibacterial activity. Structure-activity relationship (SAR) of fluoroquinolones clearly indicates that substitution at C-7 position enhances the lipophilicity of these scaffolds resultantly affording pharmacologically significant compounds. Therefore, various ciprofloxacin-oxadiazole hybrids were synthesized and characterized by spectral analysis. Cytotoxic activity of these derivatives was assessed using human liver tumor cells (Huh7). One dose anticancer test results revealed moderate cytotoxicity of the newly synthesized compounds against this cell line. As the only compound 4a depicted comparatively lower cell viability value (81.91% using 100μg/mL concentration) than the other compounds.

Topics: Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Survival; Ciprofloxacin; Drug Screening Assays, Antitumor; Humans; In Vitro Techniques; Liver Neoplasms; Magnetic Resonance Spectroscopy; Oxadiazoles

Hepatoblastoma (HB) is the most common pediatric liver malignancy. High-risk patients have poor survival, and current chemotherapies are associated with significant toxicities. Targeted therapies are needed to improve outcomes and patient quality of life. Most HB cases are TP53 wild-type; therefore, we hypothesized that targeting the p53 regulator Murine double minute 4 (MDM4) to reactivate p53 signaling may show efficacy. MDM4 expression was elevated in HB patient samples, and increased expression was strongly correlated with decreased expression of p53 target genes. Treatment with NSC207895 (XI-006), which inhibits MDM4 expression, or ATSP-7041, a stapled peptide dual inhibitor of MDM2 and MDM4, showed significant cytotoxic and antiproliferative effects in HB cells. Similar phenotypes were seen with short hairpin RNA (shRNA)-mediated inhibition of MDM4. Both NSC207895 and ATSP-7041 caused significant upregulation of p53 targets in HB cells. Knocking-down TP53 with shRNA or overexpressing MDM4 led to resistance to NSC207895-mediated cytotoxicity, suggesting that this phenotype is dependent on the MDM4-p53 axis. MDM4 inhibition also showed efficacy in a murine model of HB with significantly decreased tumor weight and increased apoptosis observed in the treatment group. This study demonstrates that inhibition of MDM4 is efficacious in HB by upregulating p53 tumor suppressor signaling.

Topics: Animals; Apoptosis; Cell Cycle Proteins; Cell Line, Tumor; Child, Preschool; Cohort Studies; Female; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Hepatoblastoma; Humans; Liver; Liver Neoplasms; Male; Mice; Oxadiazoles; Piperazines; Proto-Oncogene Proteins; Signal Transduction; Tumor Suppressor Protein p53; Up-Regulation; Xenograft Model Antitumor Assays

Stearoyl-CoA desaturase (SCD) is a central lipogenic enzyme for the synthesis of monounsaturated fatty acids (MUFA). SCD1 overexpression is associated with a genetic predisposition to hepatocarcinogenesis in mice and rats. This work hypothesized possible roles of SCD1 to genomic stability, lipogenesis, cell proliferation, and survival that contribute to the malignant transformation of non-tumorigenic liver cells. Therefore, HepG2 tumor cells were treated with the SCD1 inhibitor (CAY10566) to ensure a decrease in proliferation/survival, as confirmed by a lipidomic analysis that detected an efficient decrease in the concentration of MUFA. According to that, we switched to a model of normal hepatocytes, the HepaRG cell line, where we: (i) overexpressed SCD1 (HepaRG-SCD1 clones), (ii) inhibited the endogenous SCD1 activity with CAY10566, or (iii) treated with two monounsaturated (oleic OA and/or palmitoleic PA) fatty acids. SCD1 overexpression or MUFA stimulation increased cell proliferation, survival, and the levels of AKT, phospho-AKT(Ser473), and proliferating cell nuclear antigen (PCNA) proteins. By contrast, opposite molecular and cellular responses were observed in HepaRG cells treated with CAY10566. To assess genomic stability, HepaRG-SCD1 clones were treated with ionizing radiation (IR) and presented reduced levels of DNA damage and higher survival at doses of 5 Gy and 10 Gy compared to parental cells. In sum, this work suggests that modulation of SCD1 activity not only plays a role in cell proliferation and survival, but also in maintaining genomic stability, and therefore, contributes to a better understanding of this enzyme in molecular mechanisms of hepatocarcinogenesis projecting SCD1 as a potential translational target.

Topics: Apoptosis; Biomarkers, Tumor; Carcinoma, Hepatocellular; Cell Cycle; Cell Proliferation; Gene Expression Regulation, Neoplastic; Genomic Instability; Hepatocytes; Humans; Liver Neoplasms; Oleic Acids; Oxadiazoles; Pyridazines; Stearoyl-CoA Desaturase; Tumor Cells, Cultured

Tryptophan-2,3-dioxygenase (TDO) is an immune checkpoint enzyme expressed in human tumors and involved in immune evasion and tumor tolerance. While glutathione S-transferases (GSTs) are pharmacological targets for several cancer. Here we demonstrated the utility of NBDHEX (GSTs inhibitor) and TDO inhibitor by the combinatorial linker design. Two novel conjugates with different linkers were prepared to reverse tumor immune suppression. The conjugates displayed significant antitumor activity against TDO and GSTs expression of HepG2 cancer cells. Further study indicated that compound 4 could induce higher apoptotic effect than its mother compounds via a mitochondrial-dependent pathway, simultaneously more effective to inhibit TDO and GSTs protein expression. Further study indicated that 4 could decrease the production of kynurenine and deactivate aryl hydrocarbon receptor (AHR), leading to CD3

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Hepatocellular; Cell Line, Tumor; Drug Screening Assays, Antitumor; Enzyme Inhibitors; Glutathione Transferase; Humans; Kynurenine; Liver Neoplasms; Mitochondria; Molecular Structure; Oxadiazoles; Receptors, Aryl Hydrocarbon; Signal Transduction; Structure-Activity Relationship; T-Lymphocytes; Tryptophan Oxygenase

Overexpression of renin angiotensin system (RAS) components and nuclear factor-kappa B (NF-kB) has a key role in various cancers. Blockade of RAS and NF-kB pathway has been suggested to reduce cancer cell proliferation. This study aimed to investigate the role of angiotensin II and NF-kB pathway in liver hepatocellular carcinoma cell line (HepG2) proliferation by using azilsartan (as a novel Ag II antagonist) and Bay 11-7082 (as NF-kB inhibitor). HepG2 cells were treated with different concentrations of azilsartan and Bay 11-7082. Cytotoxicity was determined after 24, 48, and 72?h by MTT assay. Reactive oxygen spices (ROS) generation and cytochrome c release were measured following azilsartan and Bay11- 7082 treatment. Apoptosis was analyzed qualitatively by DAPI staining and quantitatively through flow cytometry methodologies and Bax and Bcl-2 mRNA and protein levels were assessed by real time PCR and ELISA methods, respectively. The cytotoxic effects of different concentration of azilsartan and Bay11- 7082 on HepG2 cells were observed as a reduction in cell viability, increased ROS formation, cytochrome c release and apoptosis induction. These effects were found to correlate with a shift in Bax level and a downward trend in the expression of Bcl-2. These findings suggest that azilsartan and Bay11- 7082 in combination or alone have strong potential as an agent for prevention or treatment of liver cancer after further studies.

Topics: Angiotensin II Type 1 Receptor Blockers; Antineoplastic Agents; Apoptosis; Benzimidazoles; Carcinoma, Hepatocellular; Cell Proliferation; Cell Survival; Cytochromes c; Hep G2 Cells; Humans; Liver Neoplasms; NF-kappa B; Nitriles; Oxadiazoles; Oxidative Stress; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Sulfones

We developed a dual-target theranostic F

Topics: Animals; Antineoplastic Agents; Apoptosis; Autophagy; Carcinoma, Hepatocellular; Cell Line, Tumor; Female; Glutathione S-Transferase pi; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Intracellular Membranes; Liver Neoplasms; Lysosomes; Mice, Inbred BALB C; Neoplasm Transplantation; Oxadiazoles; Prodrugs; Theranostic Nanomedicine

Oxadiazon (OX) is a protoporphyrinogen oxidase-inhibiting herbicide that induces porphyria and liver tumors in rodents. Although porphyria is generally considered to be a risk factor for liver tumor development, the mechanisms through which OX mediates tumor development are unclear. Therefore, in this study, we investigated the mechanisms of tumor development by focusing on constitutive active/androstane receptor (CAR), which is essential for the development of tumors in response to several chemicals. After 1, 4, or 13 weeks of dietary treatment with 1000 ppm OX, hepatic Cyp2b10 expression was induced in wild-type (WT) mice. However, this effect was blocked in CAR-knockout (CARKO) mice. Hepatic Cyp4a10 expression, indicative of peroxisome proliferator-activated receptor α (PPARα) activation, and cytotoxic changes in hepatocytes were also observed in both groups of mice. After initiation by diethylnitrosamine, 26-week treatment with OX resulted in an increase in proliferative lesions, including foci and adenomas, in both genotypes, and the incidence and multiplicity of proliferative lesions in CARKO mice were higher than those in control mice but lower than those in WT mice. These results suggested that CAR, PPARα activation, and cytotoxicity were involved in the development of liver tumors. Moreover, porphyrin was not apparently involved in OX-induced tumor development.

Topics: Animals; Carcinogenesis; Cell Death; Cells, Cultured; Constitutive Androstane Receptor; Hepatocytes; Herbicides; Liver Neoplasms; Male; Mice; Oxadiazoles; PPAR alpha; Receptors, Cytoplasmic and Nuclear

Toxicity of the SYD-1 mesoionic compound (3-[4-chloro-3-nitrophenyl]-1,2,3-oxadiazolium-5-olate) was evaluated on human liver cancer cells (HepG2) grown in either high glucose (HG) or galactose (GAL) medium, and also on suspended cells kept in HG medium. SYD-1 was able to decrease the viability of cultured HepG2 cells in a dose-dependent manner, as assessed by MTT, LDH release and dye with crystal violet assays, but no effect was observed on suspended cells after 1-40 min of treatment. Respiration analysis was performed after 2 min (suspended cells) or 24 h (cultured cells) of treatment: no change was observed in suspended cells, whereas SYD-1 inhibited as well basal, leak and uncoupled states of the respiration in cultured cells with HG medium. These inhibitions were consistent with the decrease in pyruvate level and increase in lactate level. Even more extended results were obtained with HepG2 cells grown in GAL medium where, additionally, the ATP amount was reduced. Furthermore, SYD-1 appears not to be transported by the main ABC multidrug transporters. These results show that SYD-1 is able to change the metabolism of HepG2 cells, and suggest that its cytotoxicity is related to impairment of mitochondrial metabolism. Therefore, we may propose that SYD-1 is a potential candidate for hepatocarcinoma treatment.

Topics: Adenosine Triphosphate; Antineoplastic Agents; Carcinoma, Hepatocellular; Hep G2 Cells; Hepatocytes; Humans; Lactic Acid; Liver; Liver Neoplasms; Mitochondria, Liver; Oxadiazoles; Oxidative Phosphorylation; Pyruvic Acid

N-Benzyl matrinol was obtained by hydrolysis, benzylation and reduction reaction from matrine. A series of hybrids (8a-8n) from (phenylsulfonyl)furoxan and N-benzyl matrinol were synthesized and biologically evaluated as anti-hepatocellular carcinoma agents. All target compounds were evaluated for anti-proliferative activity against human hepatocellular Bel-7402, SMMC-7721, Bel-7404, and HepG2 cells in vitro by MTT method. The results indicated that all of these compounds had potent anti-proliferative activity which were more potent than their parent compound and 5-FU, especially 8a-8h and 8j showed the strongest anti-HCC HepG2 cell activity with IC50 values of 0.12-0.93 μmol x L(-1).

Topics: Antineoplastic Agents; Carcinoma, Hepatocellular; Fluorouracil; Hep G2 Cells; Humans; Liver Neoplasms; Oxadiazoles

Novel furoxan-based nitric oxide (NO) releasing derivatives (8a-p) of farnesylthiosalicylic acid (FTS) were synthesized. Compound 8l displayed the strongest inhibition on the proliferation of human hepatocellular carcinoma (HCC) cells in vitro, superior to FTS, sorafenib, and furoxan moiety, selectively induced high frequency of HCC cell apoptosis, and produced high levels of NO in HCC cells but not in nontumor liver cells. Furthermore, 8l exhibited low acute toxicity to mice and significantly inhibited the growth of HCC tumors in vivo and the Ras-related signaling in the tumors. Therefore, our novel findings may provide a new framework for the design of new NO-releasing furoxan/FTS hybrids for the intervention of human HCC.

Topics: Animals; Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Extracellular Signal-Regulated MAP Kinases; Farnesol; Humans; Liver Neoplasms; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Nitric Oxide Donors; Oxadiazoles; Phosphorylation; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-raf; Salicylates; Stereoisomerism; Structure-Activity Relationship; Toxicity Tests, Acute; Transplantation, Heterologous

ZL11n is a novel furoxan-based nitric oxide (NO)-releasing derivative of farnesylthiosalicylic acid. In this study, we examined the anticancer effects and the potential mechanism of action of ZL11n in vitro and in vivo. It was found that ZL11n exhibited a favorable, selective cytotoxic effect in the HepG2 cell line. The yield of NO in the ZL11n treated HepG2 cells was much higher than in the control group and the normal human liver L-02 cells. Furthermore, the NO concentration was correlated to the degree of cytotoxicity observed. The ZL11n-induced apoptosis was assessed by Annexin V-FITC/propidium iodide flow cytometry assay. ZL11n triggered the mitochondrial/caspase apoptotic pathway by decreasing mitochondrial membrane potential, cytochrome c release from mitochondrial, and reducing the Bcl-2-to-Bax ratio, in addition to activating the caspase cascade. Simultaneously, we found that ZL11n treatment led to an increase in JNK and ERK1/2 phosphorylation. Furthermore, treatment with SP600125 (a JNK inhibitor) and PD98059 (an ERK1/2 inhibitor) prior to ZL11n treatment was found to significantly reverse ZL11n-induced apoptosis. The in vivo findings also revealed that ZL11n significantly reduced tumor volume and weight in the H(22) solid tumor mouse model examined. In short, our findings suggest that ZL11n induced apoptosis through the coordination of the mitochondrial apoptotic pathway (activated by NO) and MAPKs signaling pathway (triggered by JNK or ERK).

Topics: Animals; Antineoplastic Agents; Apoptosis; Carcinoma, Hepatocellular; Enzyme Activation; Farnesol; Hep G2 Cells; Humans; Liver Neoplasms; Male; Mice; Mice, Inbred ICR; Mitochondria; Mitogen-Activated Protein Kinase Kinases; Nitric Oxide; Oxadiazoles; Salicylates

A series of novel furoxan-based nitric oxide (NO)-releasing derivatives of glycyrrhetinic acid (GA) were designed, synthesized, and evaluated for their in vitro cytotoxicity against human hepatocellular carcinoma (HCC) and non-tumor liver cells. Five furoxan/GA hybrids, 7b-d, 7f, and 7g, displayed potent cytotoxicity against HCC cells (IC(50): 0.25-1.10 μM against BEL-7402 cells and 1.32-6.78 μM against HepG2 cells), but had a little effect on the growth of LO2 cells, indicating that these compounds had selective cytotoxicity against HCC cells. Furthermore, these compounds produced high concentrations of NO in HCC cells, but low in LO2 cells and treatment with hemoglobin partially reduced the cytotoxicity of the hybrid in HCC cells. Apparently, the high concentrations of NO produced by NO donor moieties and the bioactivity of GA synergistically contribute to the cytotoxicity, but the NO is a major player against HCC cells in vitro. Potentially, our findings may aid in the design of new chemotherapeutic reagents for the intervention of human HCC at clinic.

Topics: Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Glycyrrhetinic Acid; Humans; Liver Neoplasms; Nitric Oxide; Oxadiazoles

Selected 7-nitro-2,1,3-benzoxadiazole derivatives have been recently found very efficient inhibitors of glutathione S-transferase (GST) P1-1, an enzyme which displays antiapoptotic activity and is also involved in the cellular resistance to anticancer drugs. These new inhibitors are not tripeptide glutathione-peptidomimetic molecules and display lipophylic properties suitable for crossing the plasma membrane. In the present work, we show the strong cytotoxic activity of these compounds in the following four different cell lines: K562 (human myeloid leukemia), HepG2 (human hepatic carcinoma), CCRF-CEM (human T-lymphoblastic leukemia), and GLC-4 (human small cell lung carcinoma). The LC50 values are in the micromolar/submicromolar range and are close to the IC50 values obtained with GSTP1-1, suggesting that the target of these molecules inside the cell is indeed this enzyme. The cytotoxic mechanism of 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol, the most effective GSTP1-1 inhibitor, has been carefully investigated in leukemic CCRF-CEM and K562 cell lines. Western blot and immunoprecipitation analyzes have shown that 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol promotes in both cell lines the dissociation of the GSTP1-1 in a complex with c-jun NH2-terminal kinase (JNK). This process triggers a reactive oxygen species (ROS)-independent activation of the JNK-mediated pathway that results in a typical process of apoptosis. Besides this main pathway, in K562 cells, a ROS-mediated apoptosis partially occurs (about 30%) which involves the p38MAPK signal transduction pathway. The low concentration of this new compound needed to trigger cytotoxic effects on tumor cells and the low toxicity on mice indicate that the new 7-nitro-2,1,3-benzoxadiazole derivatives are promising anticancer agents.

Topics: Animals; Apoptosis; Carcinoma, Small Cell; Cell Line, Tumor; Enzyme Activation; Enzyme Inhibitors; Glutathione S-Transferase pi; Glutathione Transferase; Humans; Isoenzymes; JNK Mitogen-Activated Protein Kinases; K562 Cells; Leukemia, T-Cell; Liver Neoplasms; Lung Neoplasms; Male; Mice; Oxadiazoles; Oxidation-Reduction; p38 Mitogen-Activated Protein Kinases; Reactive Oxygen Species

HepG2 cells are highly differentiated hepatoma cells that have retained an apical, bile canalicular (BC) plasma membrane polarity. We investigated the dynamics of two BC-associated sphingolipids, glucosylceramide (GlcCer) and sphingomyelin (SM). For this, the cells were labeled with fluorescent acyl chain-labeled 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-amino]hexanoic acid (C6-NBD) derivatives of either GlcCer (C6-NBD-GlcCer) or SM (C6-NBD-SM). The pool of the fluorescent lipid analogues present in the basolateral plasma membrane domain was subsequently depleted and the apically located C6-NBD-lipid was chased at 37 degrees C. By using fluorescence microscopical analysis and a new assay that allows an accurate estimation of the fluorescent lipid pool in the apical membrane, qualitative and quantitative insight was obtained concerning kinetics, extent and (intra)cellular sites of the redistribution of apically located C6-NBD-GlcCer and C6-NBD-SM. It is demonstrated that both lipids display a preferential localization, C6-NBD-GlcCer in the apical and C6-NBD-SM in the basolateral area. Such a preference is expressed during transcytosis of both sphingolipids from the apical to the basolateral plasma membrane domain, a novel lipid trafficking route in HepG2 cells. Whereas the vast majority of the apically derived C6-NBD-SM was rapidly transcytosed to the basolateral surface, most of the apically internalized C6-NBD-GlcCer was efficiently redirected to the BC. The redirection of C6-NBD-GlcCer did not involve trafficking via the Golgi apparatus. Evidence is provided which suggests the involvement of vesicular compartments, located subjacent to the apical plasma membrane. Interestingly, the observed difference in preferential localization of C6-NBD-GlcCer and C6-NBD-SM was perturbed by treatment of the cells with dibutyryl cAMP, a stable cAMP analogue. While the preferential apical localization of C6-NBD-GlcCer was amplified, dibutyryl cAMP-treatment caused apically retrieved C6-NBD-SM to be processed via a similar pathway as that of C6-NBD-GlcCer. The data unambiguously demonstrate that segregation of GlcCer and SM occurs in the reverse transcytotic route, i.e., during apical to basolateral transport, which results in the preferential localization of GlcCer and SM in the apical and basolateral region of the cells, respectively. A role for non-Golgi-related, sub-apical vesicular compartments in the sorting of GlcCer and SM is proposed.

Topics: 4-Chloro-7-nitrobenzofurazan; Biological Transport; Bucladesine; Carcinoma, Hepatocellular; Cell Membrane; Cell Polarity; Dithionite; Fluorescent Dyes; Glucosylceramides; Golgi Apparatus; Humans; Liver; Liver Neoplasms; Monensin; Oxadiazoles; Sphingomyelins; Tumor Cells, Cultured

Carcinogenicity of eight 5-nitrofurans with heterocyclic substituents at the 2-position of the furan ring was investigated by feeding the chemicals to Sprague-Dawley female rats. N-[5-(5-nitro-2-furyl)-1,3,4-thiadiazol-2-yl]acetamide induced in 30 rats the highest incidence of tumors with the greatest number of tissues involved: forestomach squamous cell tumors (22), kidney pelvis transitional cell carcinomas (15), pulmonary alveolar cell carcinomas (16), hemangioendothelialsarcomas (20) of the intestine, mesentery, liver, lung, and pancreas, and a few tumors of other tissues. 2-Amino-5-(5-nitro-2-furyl)-1,3,4-thiadiazole, 2-amino-5-(5-nitro-2furyl)-1,3,4-oxadiazole, and trans-2-[dimethylamino)methylimino]-5-[2-(5-nitro-2-furyl)vinyl]-1,3,4-oxadiazole produced high incidences of mammary tumors. The other four 5-nitrofurans tested: N-[4-(5-NITRO-2-FURYL)-2-THIAZOLYL]ACETAMIDE;2,3,4-TRIFLUORO-N-[4-(5-NITRO-2-furyl)-2-thiazoly]acetamide;5-(5-nitro-2-furyl)-1,3,4-oxadiazol-2-ol; and N-( [3-(5-nitro-2-furyl)-1,2,4-oxadiazol-5-yl]methyl)acetamide were associated with tumor incidences of 40-60%. Two other chemicals were also tested: 2-Amino-5-nitrothiazole caused a low incidence of breast and kidney pelvis tumors, and 2-amino-4-(p-nitrophenyl)thiazole induced a high incidence of breast and salivary gland adenocarcinomas and lymphomas.

Topics: Adenocarcinoma; Adenocarcinoma, Bronchiolo-Alveolar; Administration, Oral; Amines; Animals; Carcinogens; Carcinoma, Squamous Cell; Carcinoma, Transitional Cell; Female; Hemangiosarcoma; Intestinal Neoplasms; Kidney Neoplasms; Liver Neoplasms; Lung Neoplasms; Lymphoma; Mammary Neoplasms, Experimental; Mesentery; Neoplasms, Experimental; Nitrofurans; Oxadiazoles; Pancreatic Neoplasms; Rats; Salivary Gland Neoplasms; Stomach Neoplasms; Thiadiazoles

Topics: Acetamides; Animals; Benzyl Compounds; Carcinoma, Hepatocellular; Liver; Liver Cirrhosis; Liver Neoplasms; Male; Neoplasms, Experimental; Oxadiazoles; Rats; Sydnones

Topics: Acrylamides; Administration, Oral; Animals; Azo Compounds; Carcinogens; Liver; Liver Neoplasms; Male; Morpholines; Neoplasms, Experimental; Nitrofurans; Organ Size; Oxadiazoles; Oxyphenbutazone; p-Dimethylaminoazobenzene; Rats; Semicarbazones; Testis

Topics: Antineoplastic Agents; Carcinoma, Hepatocellular; Imines; Liver Neoplasms; Mice; Neoplasms, Experimental; Oxadiazoles; Pharmacology; Rats; Research; Sarcoma; Sarcoma, Experimental; Sydnones; Toxicology