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Endocrine Connections Dec 2018We investigated the functional role of ATF2, a transcription factor normally activated via its phosphorylation in response to phospho-ERK/MAPK signals, in the outgrowth...
We investigated the functional role of ATF2, a transcription factor normally activated via its phosphorylation in response to phospho-ERK/MAPK signals, in the outgrowth of urothelial cancer. In both neoplastic and non-neoplastic urothelial cells, the expression levels of androgen receptor (AR) correlated with those of phospho-ATF2. Dihydrotestosterone treatment in AR-positive bladder cancer cells also induced the expression of phospho-ATF2 and phospho-ERK as well as nuclear translocation and transcriptional activity of ATF2. Meanwhile, ATF2 knockdown via shRNA resulted in significant decreases in cell viability, migration and invasion of AR-positive bladder cancer lines, but not AR-negative lines, as well as significant increases and decreases in apoptosis or G0/G1 cell cycle phase and S or G2/M phase, respectively. Additionally, the growth of AR-positive tumors expressing ATF2-shRNA in xenograft-bearing mice was retarded, compared with that of control tumors. ATF2 knockdown also resulted in significant inhibition of neoplastic transformation induced by a chemical carcinogen 3-methylcholanthrene, as well as the expression of Bcl-2/cyclin-A2/cyclin-D1/JUN/MMP-2, in immortalized human normal urothelial SVHUC cells stably expressing AR, but not AR-negative SVHUC cells. Finally, immunohistochemistry in surgical specimens demonstrated significant elevation of ATF2/phospho-ATF2/phospho-ERK expression in bladder tumors, compared with non-neoplastic urothelial tissues. Multivariate analysis further showed that moderate/strong ATF2 expression and phospho-ATF2 positivity were independent predictors for recurrence of low-grade tumors (hazard ratio (HR) = 2.956, P = 0.045) and cancer-specific mortality of muscle-invasive tumors (HR = 5.317, P = 0.012), respectively. Thus, ATF2 appears to be activated in urothelial cells through the AR pathway and promotes the development and progression of urothelial cancer.
PubMed: 30521479
DOI: 10.1530/EC-18-0364 -
Oncotarget Sep 2017Neoplastic cells live in a stressful context and survive thanks to their ability to overcome stress. Thus, tumor cell responses to stress are potential therapeutic...
Restoring microenvironmental redox and pH homeostasis inhibits neoplastic cell growth and migration: therapeutic efficacy of esomeprazole plus sulfasalazine on 3-MCA-induced sarcoma.
Neoplastic cells live in a stressful context and survive thanks to their ability to overcome stress. Thus, tumor cell responses to stress are potential therapeutic targets. We selected two such responses in melanoma and sarcoma cells: the xc- antioxidant system, that opposes oxidative stress, and surface v-ATPases that counteract the low pHi by extruding protons, and targeted them with the xc- blocker sulfasalazine and the proton pump inhibitor esomeprazole. Sulfasalazine inhibited the cystine/cysteine redox cycle and esomeprazole decreased pHi while increasing pHe in tumor cell lines. Although the single treatment with either drug slightly inhibited cell proliferation and motility, the association of sulfasalazine and esomeprazole powerfully decreased sarcoma and melanoma growth and migration. In the 3-methylcholanthrene (3-MCA)-induced sarcoma model, the combined therapy strongly reduced the tumor burden and increased the survival time: notably, 22 % of double-treated mice recovered and survived off therapy. Tumor-associated macrophages (TAM) displaying M2 markers, that abundantly infiltrate sarcoma and melanoma, overexpress xc- and membrane v-ATPases and were drastically decreased in tumors from mice undergone the combined therapy. Thus, the double targeting of tumor cells and macrophages by sulfasalazine and esomeprazole has a double therapeutic effect, as decreasing TAM infiltration deprives tumor cells of a crucial allied. Sulfasalazine and esomeprazole may therefore display unexpected therapeutic values, especially in case of hard-to-treat cancers.
PubMed: 28978047
DOI: 10.18632/oncotarget.18713 -
The Journal of Clinical Investigation Jun 2017NK cells are highly efficient at preventing cancer metastasis but are infrequently found in the core of primary tumors. Here, have we demonstrated that freshly isolated...
NK cells are highly efficient at preventing cancer metastasis but are infrequently found in the core of primary tumors. Here, have we demonstrated that freshly isolated mouse and human NK cells express low levels of the endo-β-D-glucuronidase heparanase that increase upon NK cell activation. Heparanase deficiency did not affect development, differentiation, or tissue localization of NK cells under steady-state conditions. However, mice lacking heparanase specifically in NK cells (Hpsefl/fl NKp46-iCre mice) were highly tumor prone when challenged with the carcinogen methylcholanthrene (MCA). Hpsefl/fl NKp46-iCre mice were also more susceptible to tumor growth than were their littermate controls when challenged with the established mouse lymphoma cell line RMA-S-RAE-1β, which overexpresses the NK cell group 2D (NKG2D) ligand RAE-1β, or when inoculated with metastatic melanoma, prostate carcinoma, or mammary carcinoma cell lines. NK cell invasion of primary tumors and recruitment to the site of metastasis were strictly dependent on the presence of heparanase. Cytokine and immune checkpoint blockade immunotherapy for metastases was compromised when NK cells lacked heparanase. Our data suggest that heparanase plays a critical role in NK cell invasion into tumors and thereby tumor progression and metastases. This should be considered when systemically treating cancer patients with heparanase inhibitors, since the potential adverse effect on NK cell infiltration might limit the antitumor activity of the inhibitors.
Topics: Animals; Cell Line, Tumor; Cytokines; Female; Heparin Lyase; Humans; Immunologic Surveillance; Killer Cells, Natural; Male; Mice; Mice, Knockout; NK Cell Lectin-Like Receptor Subfamily K; Neoplasm Invasiveness; Neoplasm Metastasis; Neoplasms, Experimental; Nuclear Matrix-Associated Proteins; Nucleocytoplasmic Transport Proteins
PubMed: 28581441
DOI: 10.1172/JCI92958 -
Fukuoka Igaku Zasshi = Hukuoka Acta... May 2015The in vitro metabolism of 2,2',3,4,4', 5,5'-heptachlorobiphenyl (CB180) was examined using liver microsomes of rats, guinea pigs and hamsters. Of liver microsomes from...
The in vitro metabolism of 2,2',3,4,4', 5,5'-heptachlorobiphenyl (CB180) was examined using liver microsomes of rats, guinea pigs and hamsters. Of liver microsomes from untreated animals, rats and guinea pigs produced one metabolite (M-1) with the activity of 1.2 and 18.1 pmol/hr/mg protein, respectively, but hamsters did not at all. Pretreatment of phenobarbital (PB) resulted in about 32-fold increase in rats, 4-fold increase in guinea pigs and an appearance of M-1 in hamsters (15 pmol/hr/mg protein). In addition, another metabolite (M-2) was formed only by liver microsomes of PB-treated guinea pigs. In contrast, pretreatment of 3-methylcholanthrene showed no metabolite in three animals. By comparison of the GC-MS data of the metabolites with synthesized authentic samples, M-1 and M-2 was determined to be 3'-hydroxy (OH)-CB180 and 4'-OH-2,2',3,4,5,5'-hexachlorobiphenyl (CB141), respectively. These results suggest that 3'-OH-CB180 is a major metabolite and is formed by PB-inducible cytochrome P450 (CYP2B enzymes) in animals and also guinea pigs possess much higher activity to metabolize CB180 than rats and hamsters.
Topics: Animals; Cricetinae; Guinea Pigs; In Vitro Techniques; Male; Microsomes, Liver; Polychlorinated Biphenyls; Rats
PubMed: 26226681
DOI: No ID Found -
Cell Reports Aug 2016Cells undergoing xenobiotic or oxidative stress activate the transcription factor nuclear factor erythroid-derived 2-like 2 (Nrf2), which initiates an intrinsic "stress...
Cells undergoing xenobiotic or oxidative stress activate the transcription factor nuclear factor erythroid-derived 2-like 2 (Nrf2), which initiates an intrinsic "stress surveillance" pathway. We recently found that the cytokine IL-17D effects a form of extrinsic stress surveillance by inducing antitumor immunity, but how IL-17D is regulated remains unknown. Here, we show that Nrf2 induced IL-17D in cancer cell lines. Moreover, both Nrf2 and IL-17D were induced in primary tumors as well as during viral infection in vivo. Expression of IL-17D in tumors and virally infected cells is essential for optimal protection of the host as il17d(-/-) mice experienced a higher incidence of tumors and exacerbated viral infections compared to wild-type (WT) animals. Moreover, activating Nrf2 to induce IL-17D in established tumors led to natural killer cell-dependent tumor regression. These data demonstrate that Nrf2 can initiate both intrinsic and extrinsic stress surveillance pathways and highlight the use of Nrf2 agonists as immune therapies for cancer and infection.
Topics: Animals; Carcinogens; Cell Line, Tumor; Chlorocebus aethiops; Gene Expression Regulation; Humans; Immunologic Surveillance; Interleukin-17; Methylcholanthrene; Mice; Mice, Inbred C57BL; Mice, Knockout; Muromegalovirus; NF-E2-Related Factor 2; Sarcoma; Signal Transduction; Soft Tissue Neoplasms; Vaccinia virus; Vero Cells
PubMed: 27545889
DOI: 10.1016/j.celrep.2016.07.075 -
International Journal of Molecular... May 2019TCDD-inducible poly-ADP-ribose polymerase (TIPARP) is an aryl hydrocarbon receptor (AHR) target gene that functions as part of a negative feedback loop to repress AHR...
TCDD-inducible poly-ADP-ribose polymerase (TIPARP) is an aryl hydrocarbon receptor (AHR) target gene that functions as part of a negative feedback loop to repress AHR activity. mice exhibit increased sensitivity to the toxicological effects of 2,3,7,8-tetrachlorodibenzo--dioxin (TCDD), including lethal wasting syndrome. However, it is not known whether mice also exhibit increased sensitivity to other AHR ligands. In this study, we treated male or wild type (WT) mice with a single injection of 100 mg/kg 3-methylcholanthrene (3MC). Consistent with TIPARP's role as a repressor of AHR signaling, 3MC-treated mice exhibited increased hepatic Cyp1a1 and Cyp1b1 levels compared with WT mice. No 3MC-treated mice survived beyond day 16 and the mice exhibited chylous ascites characterized by an accumulation of fluid in the peritoneal cavity. All WT mice survived the 30-day treatment and showed no signs of fluid accumulation. Treated mice also exhibited a transient and mild hepatotoxicity with inflammation. 3MC-treated WT, but not mice, developed mild hepatic steatosis. Lipid deposits accumulated on the surface of the liver and other abdominal organs in the 3MC- mice. Our study reveals that mice have increased sensitivity to 3MC-induced liver toxicity, but unlike with TCDD, lethality is due to chylous ascites rather than wasting syndrome.
Topics: Adipose Tissue; Animals; Azo Compounds; Chylous Ascites; Cytokines; Fatty Liver; Gene Expression Regulation, Enzymologic; Inflammation; Inflammation Mediators; Liver; Male; Methylcholanthrene; Mice, Knockout; Poly(ADP-ribose) Polymerases; Polychlorinated Dibenzodioxins; Pyrazoles; Receptors, Aryl Hydrocarbon; Signal Transduction; Survival Analysis
PubMed: 31083300
DOI: 10.3390/ijms20092312 -
Biochemical and Biophysical Research... Mar 2017Aryl hydrocarbon receptor (AhR) has been increasingly recognized to play a crucial role in normal physiological homeostasis. Additionally, disrupted AhR signaling leads...
Aryl hydrocarbon receptor (AhR) has been increasingly recognized to play a crucial role in normal physiological homeostasis. Additionally, disrupted AhR signaling leads to several pathological states in the lung and liver. AhR activation transcriptionally induces detoxifying enzymes such as cytochrome P450 (CYP) 1A and NAD(P)H quinone dehydrogenase 1 (NQO1). The toxicity profiles of the classical AhR ligands such as 3-methylcholanthrene and dioxins limit their use as a therapeutic agent in humans. Hence, there is a need to identify nontoxic AhR ligands to develop AhR as a clinically relevant druggable target. Recently, we demonstrated that leflunomide, a FDA approved drug, used to treat rheumatoid arthritis in humans, induces CYP1A enzymes in adult mice via the AhR. However, the mechanisms by which this drug induces NQO1 in vivo are unknown. Therefore, we tested the hypothesis that leflunomide will induce pulmonary and hepatic NQO1 enzyme in neonatal mice via AhR-dependent mechanism(s). Leflunomide elicited significant induction of pulmonary CYP1A1 and NQO1 expression in neonatal mice. Interestingly, the dose at which leflunomide increased NQO1 was significantly higher than that required to induce CYP1A1 enzyme. Likewise, it also enhanced hepatic CYP1A1, 1A2 and NQO1 expression in WT mice. In contrast, leflunomide failed to induce these enzymes in AhR-null mice. Our results indicate that leflunomide induces pulmonary and hepatic CYP1A and NQO1 enzymes via the AhR in neonatal mice. These findings have important implications to prevent and/or treat disorders such as bronchopulmonary dysplasia in human infants where AhR may play a crucial role in the disease pathogenesis.
Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Cytochrome P-450 CYP1A1; Gene Deletion; Immunologic Factors; Isoxazoles; Leflunomide; Mice; Mice, Inbred C57BL; NAD(P)H Dehydrogenase (Quinone); Receptors, Aryl Hydrocarbon; Up-Regulation
PubMed: 28192119
DOI: 10.1016/j.bbrc.2017.02.051 -
European Journal of Immunology Jun 2021Therapeutic antibodies blocking PD-1-/PD-L1 interaction have achieved remarkable clinical success in cancer. In addition to blocking a target molecule, some isotypes of... (Comparative Study)
Comparative Study
Therapeutic antibodies blocking PD-1-/PD-L1 interaction have achieved remarkable clinical success in cancer. In addition to blocking a target molecule, some isotypes of antibodies can activate complement, NK cells or phagocytes, resulting in death of the cell expressing the antibody's target. Human anti-PD-1 therapeutics use antibody isotypes designed to minimize such antibody-dependent lysis. In contrast, anti-PD-1 reagents used in mice are derived from multiple species, with different isotypes, and are not engineered to reduce target cell death: few studies analyze or discuss how antibody species and isotype may impact data interpretation. We demonstrate here that anti-PD-1 therapy to promote activation and proliferation of murine PD-1-expressing CD8 T cells sometimes led instead to a loss of antigen specific cells. This phenomenon was seen in two tumor models and a model of virus infection, and varied with the clone of anti-PD-1 antibody. Additionally, we compared competition among anti-PD-1 clones to find a combination that allows detection of PD-1-expressing cells despite the presence of blocking anti-PD1 antibodies in vivo. These data bring attention to the possibility of unintended target cell depletion with some commonly used anti-mouse PD-1 clones, and should provide a valuable resource for the design and interpretation of anti-PD-1 studies in mice.
Topics: Animals; B7-H1 Antigen; CD8-Positive T-Lymphocytes; Cell Death; Cell Line, Tumor; Cricetinae; Disease Models, Animal; Drug Evaluation, Preclinical; Herpesviridae Infections; Humans; Immune Checkpoint Inhibitors; Immunoglobulin G; Immunoglobulin Isotypes; Immunotherapy; Methylcholanthrene; Mice; Mice, Inbred C57BL; Muromegalovirus; Programmed Cell Death 1 Receptor; Rats; Sarcoma; Skin Neoplasms
PubMed: 33684223
DOI: 10.1002/eji.202048960 -
Oncoimmunology 2017The cytokine-induced SH2-containing protein CIS belongs to the suppressor of cytokine signaling (SOCS) protein family. Here, we show the critical role of CIS in...
The cytokine-induced SH2-containing protein CIS belongs to the suppressor of cytokine signaling (SOCS) protein family. Here, we show the critical role of CIS in suppressing natural killer (NK) cell control of tumor initiation and metastasis. -deficient mice were highly resistant to methylcholanthrene-induced sarcoma formation and protected from lung metastasis of B16F10 melanoma and RM-1 prostate carcinoma cells. In contrast, the growth of primary subcutaneous tumors, including those expressing the foreign antigen OVA, was unchanged in -deficient mice. The combination of deficiency and relevant targeted and immuno-therapies such as combined BRAF and MEK inhibitors, immune checkpoint blockade antibodies, IL-2 and type I interferon revealed further improved control of metastasis. The data clearly indicate that targeting CIS promotes NK cell antitumor functions and CIS holds great promise as a novel target in NK cell immunotherapy.
PubMed: 28344878
DOI: 10.1080/2162402X.2016.1267892 -
Diabetologia Jan 2020Exposure to environmental pollution has been consistently linked to diabetes incidence in humans, but the potential causative mechanisms remain unclear. Given the...
AIMS/HYPOTHESIS
Exposure to environmental pollution has been consistently linked to diabetes incidence in humans, but the potential causative mechanisms remain unclear. Given the critical role of regulated insulin secretion in maintaining glucose homeostasis, environmental chemicals that reach the endocrine pancreas and cause beta cell injury are of particular concern. We propose that cytochrome P450 (CYP) enzymes, which are involved in metabolising xenobiotics, could serve as a useful biomarker for direct exposure of islets to pollutants. Moreover, functional CYP enzymes in islets could also impact beta cell physiology. The aim of this study was to determine whether CYP1A enzymes are activated in islets following direct or systemic exposure to environmental pollutants.
METHODS
Immortalised liver (HepG2) and rodent pancreatic endocrine cell lines (MIN6, βTC-6, INS1, α-TC1, α-TC3), as well as human islets, were treated in vitro with known CYP1A inducers 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 3-methylcholanthrene (3-MC). In addition, mice were injected with either a single high dose of TCDD or multiple low doses of TCDD in vivo, and islets were isolated 1, 7 or 14 days later.
RESULTS
CYP1A enzymes were not activated in any of the immortalised beta or alpha cell lines tested. However, both 3-MC and TCDD potently induced CYP1A1 gene expression and modestly increased CYP1A1 enzyme activity in human islets after 48 h. The induction of CYP1A1 in human islets by TCDD was prevented by cotreatment with a cytokine mixture. After a systemic single high-dose TCDD injection, CYP1A1 enzyme activity was induced in mouse islets ~2-fold, ~40-fold and ~80-fold compared with controls after 1, 7 and 14 days, respectively, in vivo. Multiple low-dose TCDD exposure in vivo also caused significant upregulation of Cyp1a1 in mouse islets. Direct TCDD exposure to human and mouse islets in vitro resulted in suppressed glucose-induced insulin secretion. A single high-dose TCDD injection resulted in lower plasma insulin levels, as well as a pronounced increase in beta cell death.
CONCLUSIONS/INTERPRETATION
Transient exposure to TCDD results in long-term upregulation of CYP1A1 enzyme activity in islets. This provides evidence for direct exposure of islets to lipophilic pollutants in vivo and may have implications for islet physiology.
Topics: Animals; Blood Glucose; Cell Line; Cytochrome P-450 CYP1A1; Cytochrome P-450 CYP1A2; Environmental Pollutants; Hep G2 Cells; Humans; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Polychlorinated Dibenzodioxins; Real-Time Polymerase Chain Reaction
PubMed: 31776611
DOI: 10.1007/s00125-019-05035-0