1
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Guven C, Taskin E, Aydın Ö, Kaya ST, Sevgiler Y. Diazoxide attenuates DOX-induced cardiotoxicity in cultured rat myocytes. Biotech Histochem 2024; 99:113-124. [PMID: 38439686 DOI: 10.1080/10520295.2024.2324368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2024] Open
Abstract
Doxorubicin (DOX)-induced cardiotoxicity is a well known clinical problem, and many investigations have been made of its possible amelioration. We have investigated whether diazoxide (DIA), an agonist at mitochondrial ATP-sensitive potassium channels (mitoKATP), could reverse DOX-induced apoptotic myocardial cell loss, in cultured rat cardiomyocytes. The role of certain proteins in this pathway was also studied. The rat cardiomyocyte cell line (H9c2) was treated with DOX, and also co-treated with DOX and DIA, for 24 h. Distribution of actin filaments, mitochondrial membrane potential, superoxide dismutase (SOD) activity, total oxidant and antioxidant status (TOS and TAS, respectively), and some protein expressions, were assessed. DOX significantly decreased SOD activity, increased ERK1/2 protein levels, and depolarised the mitochondrial membrane, while DIA co-treatment inhibited such changes. DIA co-treatment ameliorated DOX-induced cytoskeletal changes via F-actin distribution and mitoKATP structure. Co-treatment also decreased ERK1/2 and cytochrome c protein levels. Cardiomyocyte loss due to oxidative stress-mediated apoptosis is a key event in DOX-induced cytotoxicity. DIA had protective effects on DOX-induced cardiotoxicity, via mitoKATP integrity, especially with elevated SUR2A levels; but also by a cascade including SOD/AMPK/ERK1/2. Therefore, DIA may be considered a candidate agent for protecting cardiomyocytes against DOX chemotherapy.
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Affiliation(s)
- Celal Guven
- Department of Biophysics, Faculty of Medicine, Adıyaman University, Adıyaman, Turkey
| | - Eylem Taskin
- Department of Physiology, Faculty of Medicine, Adıyaman University, Adıyaman, Turkey
| | - Özgül Aydın
- Department of Biology, Institute of Natural and Applied Sciences, Adıyaman University, Adıyaman, Turkey
| | - Salih Tunç Kaya
- Department of Biology, Faculty of Science and Letters, Düzce University, Düzce, Turkey
| | - Yusuf Sevgiler
- Department of Biology, Faculty of Science and Letters, Adıyaman University, Adıyaman, Turkey
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2
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Gabriel KA, Streicher JM. HSP90 inhibition in the mouse spinal cord enhances opioid signaling by suppressing an AMPK-mediated negative feedback loop. Sci Signal 2023; 16:eade2438. [PMID: 37040443 PMCID: PMC11010773 DOI: 10.1126/scisignal.ade2438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 03/22/2023] [Indexed: 04/13/2023]
Abstract
Opioids and other agonists of the μ-opioid receptor are effective at managing acute pain, but their chronic use can lead to tolerance that limits their efficacy. We previously reported that inhibiting the chaperone protein HSP90 in the spinal cords of mice promotes the antinociceptive effects of opioids in a manner that involved increased activation of the kinase ERK. Here, we found that the underlying mechanism involves the relief of a negative feedback loop mediated by the kinase AMPK. Intrathecal treatment of male and female mice with the HSP90 inhibitor 17-AAG decreased the abundance of the β1 subunit of AMPK in the spinal cord. The antinociceptive effects of 17-AAG with morphine were suppressed by intrathecal administration of AMPK activators and enhanced by an AMPK inhibitor. Opioid treatment increased the abundance of phosphorylated AMPK in the dorsal horn of the spinal cord, where it colocalized with a neuronal marker and the neuropeptide CGRP. Knocking down AMPK in CGRP-positive neurons enhanced the antinociceptive effects of morphine and demonstrated that AMPK mediated the signal transduction between HSP90 inhibition and ERK activation. These data suggest that AMPK mediates an opioid-induced negative feedback loop in CGRP neurons of the spinal cord and that this loop can be disabled by HSP90 inhibition to enhance the efficacy of opioids.
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Affiliation(s)
- Katherin A. Gabriel
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson AZ USA
| | - John M. Streicher
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson AZ USA
- Comprehensive Pain and Addiction Center, University of Arizona, Tucson AZ USA
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3
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Cui X, Chen F, Zhao J, Li D, Hu M, Chen X, Zhang Y, Han L. Involvement of JNK signaling in Aspergillus fumigatus-induced inflammatory factors release in bronchial epithelial cells. Sci Rep 2023; 13:1293. [PMID: 36690696 PMCID: PMC9871034 DOI: 10.1038/s41598-023-28567-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 01/20/2023] [Indexed: 01/25/2023] Open
Abstract
Aspergillus fumigatus (A. fumigatus) is an important fungal pathogen and its conidia can be inhaled and interact with airway epithelial cells; however, the release of inflammatory factors from bronchial epithelial cells upon A. fumigatus infection and its regulation remained unclear. Here it was demonstrated that the release of IL-27, MCP-1 and TNF-α from BEAS-2B cells were upregulated upon stimulation by conidia, while mitogen-activated protein kinase signaling pathway was activated. Further, the inhibition of JNK, but not p38 and ERK, could inhibit inflammatory factors release and the LC3II formation in BEAS-2B cells induced by A. fumigatus conidia. In addition, an inhibitor of autophagy, bafilomycin A1 was able to significantly down-regulate the release of inflammatory factors in BEAS-2B cells upon A. fumigatus conidia, while rapamycin could reverse the effect of JNK inhibitor on IL-27 and TNF-α release. Taken together, these data demonstrated that JNK signal might play an important role in inflammatory factor release regulated by autophagy in bronchial epithelial cells against A. fumigatus infection.
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Affiliation(s)
- Xiao Cui
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, 100069, China
| | - Fangyan Chen
- Department for Disinfection and Infection Control, Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Jingya Zhao
- Department for Disinfection and Infection Control, Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Dingchen Li
- Department for Disinfection and Infection Control, Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Mandong Hu
- National Center of Biomedical Analysis, 27 Taiping Lu, Beijing, 100850, China
| | - Xue Chen
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, 100069, China
| | - Yulin Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, 100069, China.
| | - Li Han
- Department for Disinfection and Infection Control, Chinese PLA Center for Disease Control and Prevention, Beijing, China.
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4
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Antimycin A induced apoptosis in HCT-116 colorectal cancer cells through the up- and downregulation of multiple signaling pathways. Med Oncol 2022; 40:51. [DOI: 10.1007/s12032-022-01901-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 11/16/2022] [Indexed: 12/23/2022]
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5
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Lai HT, Naumova N, Marchais A, Gaspar N, Geoerger B, Brenner C. Insight into the interplay between mitochondria-regulated cell death and energetic metabolism in osteosarcoma. Front Cell Dev Biol 2022; 10:948097. [PMID: 36072341 PMCID: PMC9441498 DOI: 10.3389/fcell.2022.948097] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
Osteosarcoma (OS) is a pediatric malignant bone tumor that predominantly affects adolescent and young adults. It has high risk for relapse and over the last four decades no improvement of prognosis was achieved. It is therefore crucial to identify new drug candidates for OS treatment to combat drug resistance, limit relapse, and stop metastatic spread. Two acquired hallmarks of cancer cells, mitochondria-related regulated cell death (RCD) and metabolism are intimately connected. Both have been shown to be dysregulated in OS, making them attractive targets for novel treatment. Promising OS treatment strategies focus on promoting RCD by targeting key molecular actors in metabolic reprogramming. The exact interplay in OS, however, has not been systematically analyzed. We therefore review these aspects by synthesizing current knowledge in apoptosis, ferroptosis, necroptosis, pyroptosis, and autophagy in OS. Additionally, we outline an overview of mitochondrial function and metabolic profiles in different preclinical OS models. Finally, we discuss the mechanism of action of two novel molecule combinations currently investigated in active clinical trials: metformin and the combination of ADI-PEG20, Docetaxel and Gemcitabine.
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Affiliation(s)
- Hong Toan Lai
- CNRS, Institut Gustave Roussy, Aspects métaboliques et systémiques de l’oncogénèse pour de nouvelles approches thérapeutiques, Université Paris-Saclay, Villejuif, France
| | - Nataliia Naumova
- CNRS, Institut Gustave Roussy, Aspects métaboliques et systémiques de l’oncogénèse pour de nouvelles approches thérapeutiques, Université Paris-Saclay, Villejuif, France
| | - Antonin Marchais
- INSERM U1015, Gustave Roussy Cancer Campus, Université Paris-Saclay, Villejuif, France
- Department of Pediatric and Adolescent Oncology, Gustave Roussy Cancer Campus, Villejuif, France
| | - Nathalie Gaspar
- INSERM U1015, Gustave Roussy Cancer Campus, Université Paris-Saclay, Villejuif, France
- Department of Pediatric and Adolescent Oncology, Gustave Roussy Cancer Campus, Villejuif, France
| | - Birgit Geoerger
- INSERM U1015, Gustave Roussy Cancer Campus, Université Paris-Saclay, Villejuif, France
- Department of Pediatric and Adolescent Oncology, Gustave Roussy Cancer Campus, Villejuif, France
| | - Catherine Brenner
- CNRS, Institut Gustave Roussy, Aspects métaboliques et systémiques de l’oncogénèse pour de nouvelles approches thérapeutiques, Université Paris-Saclay, Villejuif, France
- *Correspondence: Catherine Brenner,
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6
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Chen F, Zhao CY, Guan JF, Liu XC, Li XF, Xie DZ, Xu C. High-Carbohydrate Diet Alleviates the Oxidative Stress, Inflammation and Apoptosis of Megalobrama amblycephala Following Dietary Exposure to Silver Nanoparticles. Antioxidants (Basel) 2021; 10:antiox10091343. [PMID: 34572975 PMCID: PMC8471270 DOI: 10.3390/antiox10091343] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/02/2021] [Accepted: 08/23/2021] [Indexed: 01/04/2023] Open
Abstract
A 12-week feeding trial was performed to evaluate the effects of high-carbohydrate diet on oxidative stress, inflammation and apoptosis induced by silver nanoparticles (Ag-NPs) in M. amblycephala. Fish (20.12 ± 0.85 g) were randomly fed four diets (one control diet (C, 30% carbohydrate), one control diet supplemented with 100 mg kg−1 Ag-NPs (CS), one high-carbohydrate diet (HC, 45% carbohydrate) and one HC diet supplemented with 100 mg kg−1 Ag-NPs (HCS)). The results indicated that weight gain rate (WGR), specific growth rate (SGR), antioxidant enzyme (SOD and CAT) activities and expression of Trx, Cu/Zn-SOD, Mn-SOD, CAT and GPx1 of fish fed CS diet were all remarkably lower than those of other groups, whereas the opposite was true for plasma IL 1β and IL 6 levels, liver ROS contents, hepatocytes apoptotic rate, AMP/ATP ratio, AMPKα, P 53 and caspase 3 protein contents and mRNA levels of AMPKα 1, AMPKα 2, TXNIP, NF-κB, TNFα, IL 1β, IL 6, P 53, Bax and caspase 3. However, high-carbohydrate diet remarkably increased WGR, SGR, liver SOD and CAT activities, AMPKα protein content and mRNA levels of antioxidant genes (Cu/Zn-SOD, Mn-SOD, CAT and GPx1), anti-inflammatory cytokines (IL 10) and anti-apoptotic genes (Bcl 2) of fish facing Ag-NPs compared with the CS group, while the opposite was true for liver ROS contents, hepatocytes apoptotic rate, P 53 and caspase 3 protein contents, as well as mRNA levels of TXNIP, NF-κB, TNFα, IL 1β, IL 6, P 53, Bax and caspase 3. Overall, high-carbohydrate diet could attenuate Ag-NPs-induced hepatic oxidative stress, inflammation and apoptosis of M. amblycephala through AMPK activation.
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Affiliation(s)
- Fang Chen
- College of Marine Sciences, South China Agricultural University, No.483 Wushan Road, Guangzhou 510642, China; (F.C.); (J.-F.G.); (X.-C.L.); (D.-Z.X.)
| | - Cai-Yuan Zhao
- State Key Laboratory of Biocontrol, Southern Marine Sciences and Engineering Guangdong Laboratory (Zhuhai), School of Marine Sciences, Sun Yat-Sen University, Guangzhou 510275, China;
| | - Jun-Feng Guan
- College of Marine Sciences, South China Agricultural University, No.483 Wushan Road, Guangzhou 510642, China; (F.C.); (J.-F.G.); (X.-C.L.); (D.-Z.X.)
| | - Xiao-Cheng Liu
- College of Marine Sciences, South China Agricultural University, No.483 Wushan Road, Guangzhou 510642, China; (F.C.); (J.-F.G.); (X.-C.L.); (D.-Z.X.)
| | - Xiang-Fei Li
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang Road, Nanjing 210095, China;
| | - Di-Zhi Xie
- College of Marine Sciences, South China Agricultural University, No.483 Wushan Road, Guangzhou 510642, China; (F.C.); (J.-F.G.); (X.-C.L.); (D.-Z.X.)
| | - Chao Xu
- College of Marine Sciences, South China Agricultural University, No.483 Wushan Road, Guangzhou 510642, China; (F.C.); (J.-F.G.); (X.-C.L.); (D.-Z.X.)
- Correspondence:
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7
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Exopolysaccharides isolated from Rhizopus nigricans induced colon cancer cell apoptosis in vitro and in vivo via activating the AMPK pathway. Biosci Rep 2021; 40:221749. [PMID: 31894839 PMCID: PMC6960068 DOI: 10.1042/bsr20192774] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 12/30/2019] [Accepted: 12/31/2019] [Indexed: 12/13/2022] Open
Abstract
Colorectal cancer (CRC) is a leading cause of cancer-related human deaths. The exopolysaccharide (EPS1-1), isolated from Rhizopus nigricans, has been described as exhibiting anti-tumor and pro-apoptotic activity against CRC, although the underlying mechanism is poorly understood. Herein, we investigate how EPS1-1 induces apoptosis of CRC cells in vitro and in vivo. Our results show that, in vitro, EPS1-1 suppressed cell growth and facilitated apoptosis in a dose- and time-dependent manner by activating the AMP-activated protein kinase (AMPK) pathway in mouse colon cancer CT26 cells. However, treatment with small interfering RNAs (siRNAs) targeting AMPKα or with compound C, an AMPK inhibitor, interfered with the pro-apoptosis effects of EPS1-1. We also show that EPS1-1 initiated the release of reactive oxygen species (ROS) and liver kinase B1 (LKB1), both of which are necessary signals for AMPK activation. Furthermore, EPS1-1-mediated apoptosis is regulated by inactivation of mammalian target of rapamycin complex 1 (mTORC1) and activation of the jun-NH2 kinase (JNK)-p53 signaling axis dependent on AMPK activation. In vivo, azoxymethane/dextran sulfate sodium (AOM/DSS)-treated CRC mice, when administered EPS1-1, exhibited activation of the AMPK pathway, inhibition of mTORC1, and accumulation of p53 in tumor tissues. Collectively, these findings suggest that EPS1-1-induced apoptosis relies on the activation of the AMPK pathway. The present study provides evidence suggesting that EPS1-1 may be an effective target for development of novel CRC therapeutic agents.
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8
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Huang C, Zhao J, Luo C, Zhu Z. Overexpression of DGKI in Gastric Cancer Predicts Poor Prognosis. Front Med (Lausanne) 2020; 7:320. [PMID: 32733904 PMCID: PMC7358307 DOI: 10.3389/fmed.2020.00320] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 06/01/2020] [Indexed: 12/24/2022] Open
Abstract
Background: Diacylglycerol kinase iota (DGKI) is overexpressed in a variety of cancers and is associated with poor prognosis in colon cancer. This study evaluated the prognostic value of DGKI in gastric cancer (GC) using data from The Cancer Genome Atlas (TCGA). Methods: RNA sequencing results and clinical data of gastric adenoma and adenocarcinoma samples were obtained from the TCGA database (https://portal.gdc.cancer.gov). The Wilcoxon or Kruskal–Wallis test and logistic regression were used to analyze the relationship between DGKI and the clinicopathological characteristics of GC patients. Univariate Cox regression and Kaplan-Meier analysis were used to analyze the clinicopathological characteristics of GC patients and the relationship between DGKI and overall survival time, and multivariate Cox regression analysis was used to identify independent risk factors affecting the prognosis of GC patients. Gene set enrichment analysis (GSEA) was performed using the TCGA dataset. Results: DGKI was overexpressed in gastric tumors and was related to poor prognosis (p = 0.003). Overexpression of DGKI in GC was significantly correlated with high grade (OR = 1.71 for G3 vs. G2), stage (OR = 2.08 for II vs. I) and T classification (OR = 4.64 for T4 vs. T1; OR = 3.99 for T3 vs. T1; OR = 3.37 for T2 vs. T1) (all p <0.05). DGKI (OR = 7.34; p = 0.000) was an independent risk factor affecting the survival of GC patients. The MAPK signaling pathway was differentially enriched with DGKI overexpression. Conclusion: DGKI overexpression may be a potential molecular marker for poor prognosis in GC. The MAPK signaling pathway may be one of the key pathways related to DGKI regulation in GC.
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Affiliation(s)
- Chao Huang
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jiefeng Zhao
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Chen Luo
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Zhengming Zhu
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
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9
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Wang LY, Zhao S, Lv GJ, Ma XJ, Zhang JB. Mechanisms of resveratrol in the prevention and treatment of gastrointestinal cancer. World J Clin Cases 2020; 8:2425-2437. [PMID: 32607320 PMCID: PMC7322414 DOI: 10.12998/wjcc.v8.i12.2425] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 05/20/2020] [Accepted: 05/23/2020] [Indexed: 02/05/2023] Open
Abstract
Gastrointestinal (GI) cancer is one of the leading causes of cancer-related deaths worldwide. According to the Global Cancer Statistics, colorectal cancer is the second leading cause of cancer-related mortality, closely followed by gastric cancer (GC). Environmental, dietary, and lifestyle factors including cigarette smoking, alcohol intake, and genetics are the most important risk factors for GI cancer. Furthermore, infections caused by Helicobacter pylori are a major cause of GC initiation. Despite improvements in conventional therapies, including surgery, chemotherapy, and radiotherapy, the length or quality of life of patients with advanced GI cancer is still poor because of delayed diagnosis, recurrence and side effect. Resveratrol (3, 4, 5-trihydroxy-trans-stilbene; Res), a natural polyphenolic compound, reportedly has various pharmacologic functions including anti-oxidant, anti-inflammatory, anti-cancer, and cardioprotective functions. Many studies have demonstrated that Res also exerts a chemopreventive effect on GI cancer. Research investigating the anti-cancer mechanism of Res for the prevention and treatment of GI cancer has implicated multiple pathways including oxidative stress, cell proliferation, and apoptosis. Therefore, this paper provides a review of the function and molecular mechanisms of Res in the prevention and treatment of GI cancer.
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Affiliation(s)
- Li-Yan Wang
- Department of Pharmacy, the First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning Province, China
| | - Shan Zhao
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, China
| | - Guo-Jun Lv
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, China
| | - Xiao-Jun Ma
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, China
| | - Jian-Bin Zhang
- College of Pharmacy, Dalian Medical University, Dalian 116044, Liaoning Province, China
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10
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Renoprotective effects of vitamin D3 supplementation in a rat model of metabolic syndrome. Eur J Nutr 2020; 60:299-316. [PMID: 32322970 DOI: 10.1007/s00394-020-02249-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 04/01/2020] [Indexed: 01/24/2023]
Abstract
PURPOSE The study aimed to investigate the potential nephroprotective effects of vitamin D3 in metabolic syndrome (MetS) and the molecular basis of the underlying mechanisms of its action. METHODS MetS was induced in adult male Wistar rats by adding fructose (10%) to every day drinking water and salt (3%) to the diet. Six weeks after fructose/salt consumption, fasting serum lipid profile and uric acid levels were determined, an oral glucose tolerance test (OGTT) was performed and kidney function was checked. MetS rats were then treated orally with vitamin D3 (10 µg/kg/day) for 6 weeks. At the end of the study period (12 weeks), the OGTT test was reperformed, anthropometrical parameters were measured, urine, blood and tissue samples were collected and the animals were euthanised. RESULTS The incidence of MetS was confirmed 6 weeks after fructose/salt consumption, when the rats exhibited significant weight gain, dyslipidemia, hyperuricemia, insulin resistance, hyperinsulinemia and impaired glucose tolerance. After 12 weeks, MetS rats displayed markedly declined renal function alongside with extravagant renal histopathological damages and interstitial fibrosis. Furthermore, significantly enhanced renal oxidative stress and inflammation were manifested. Vitamin D3 supplementation in MetS rats significantly reversed all the above-mentioned deleterious effects. CONCLUSION The study has indeed provided mounting evidence of the promising therapeutic potential of vitamin D3 against development and progression of MetS-induced nephropathy. A new insight has been introduced into the crucial role of dipeptidyl peptidase-4 inhibition and sirtuin-1/5'adenosine monophosphate-activated protein kinase activation in the renoprotective effects of vitamin D3.
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11
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Taskin E, Guven C, Kaya ST, Sahin L, Kocahan S, Degirmencioglu AZ, Gur FM, Sevgiler Y. The role of toll-like receptors in the protective effect of melatonin against doxorubicin-induced pancreatic beta cell toxicity. Life Sci 2019; 233:116704. [DOI: 10.1016/j.lfs.2019.116704] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 07/26/2019] [Accepted: 07/26/2019] [Indexed: 02/08/2023]
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12
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Teramoto K, Katoh H. The cystine/glutamate antiporter xCT is a key regulator of EphA2 S897 phosphorylation under glucose-limited conditions. Cell Signal 2019; 62:109329. [PMID: 31152846 DOI: 10.1016/j.cellsig.2019.05.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 05/27/2019] [Accepted: 05/28/2019] [Indexed: 01/06/2023]
Abstract
EphA2, which belongs to the Eph family of receptor tyrosine kinases, is overexpressed in a variety of human cancers. Serine 897 (S897) phosphorylation of EphA2 is known to promote cancer cell migration and proliferation in a ligand-independent manner. In this study, we show that glucose deprivation induces S897 phosphorylation of EphA2 in glioblastoma cells. The phosphorylation requires the activity of the cystine/glutamate antiporter xCT and reactive oxygen species (ROS)-dependent ERK and RSK activation. Furthermore, depletion of EphA2 in glioblastoma cells leads to decreased cell viability under glucose starvation. Our results suggest a role of EphA2 in glioblastoma cell viability under glucose-limited conditions.
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Affiliation(s)
- Koji Teramoto
- Laboratory of Molecular Neurobiology, Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hironori Katoh
- Laboratory of Molecular Neurobiology, Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Laboratory of Molecular Neurobiology, Graduate School of Biostudies, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
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13
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Safe S, Nair V, Karki K. Metformin-induced anticancer activities: recent insights. Biol Chem 2018; 399:321-335. [PMID: 29272251 DOI: 10.1515/hsz-2017-0271] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/11/2017] [Indexed: 12/12/2022]
Abstract
Metformin is a widely used antidiabetic drug, and there is evidence among diabetic patients that metformin is a chemopreventive agent against multiple cancers. There is also evidence in human studies that metformin is a cancer chemotherapeutic agent, and several clinical trials that use metformin alone or in combination with other drugs are ongoing. In vivo and in vitro cancer cell culture studies demonstrate that metformin induces both AMPK-dependent and AMPK-independent genes/pathways that result in inhibition of cancer cell growth and migration and induction of apoptosis. The effects of metformin in cancer cells resemble the patterns observed after treatment with drugs that downregulate specificity protein 1 (Sp1), Sp3 and Sp4 or by knockdown of Sp1, Sp3 and Sp4 by RNA interference. Studies in pancreatic cancer cells clearly demonstrate that metformin decreases expression of Sp1, Sp3, Sp4 and pro-oncogenic Sp-regulated genes, demonstrating that one of the underlying mechanisms of action of metformin as an anticancer agent involves targeting of Sp transcription factors. These observations are consistent with metformin-mediated effects on genes/pathways in many other tumor types.
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Affiliation(s)
- Stephen Safe
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, 4466 TAMU, College Station, TX 77843-4466, USA
| | - Vijayalekshmi Nair
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, 4466 TAMU, College Station, TX 77843-4466, USA
| | - Keshav Karki
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, 4466 TAMU, College Station, TX 77843-4466, USA
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14
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Lee JH, Lee HJ, Sim DY, Jung JH, Kim KR, Kim SH. Apoptotic effect of lambertianic acid through AMPK/FOXM1 signaling in MDA-MB231 breast cancer cells. Phytother Res 2018; 32:1755-1763. [PMID: 29722086 DOI: 10.1002/ptr.6105] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 01/05/2023]
Abstract
Though lambertianic acid (LA) was known to exert antitumor effect in liver and prostate cancers, its underlying anticancer mechanism is never reported in breast cancers so far. Thus, in this study, apoptotic mechanism of LA was elucidated in MDA-MB-231 breast cancer cells. Here, LA increased cytotoxicity in MCF-7 and MDA-MB-231 cells; enhanced sub-G1 population, G2/M arrest, and cleaved poly(ADP-ribose) polymerase; activated phosphorylation of AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase pathway; and also suppressed phosphorylation of AKT and the expression of forkhead box M1 (FOXM1), X-linked inhibitor of apoptosis protein, B-cell lymphoma 2, and CyclinB1 in MDA-MB-231 cells. Furthermore, AMPK inhibitor compound C reversed the effect of LA on FOXM1, Cyclin B1, and cleaved poly(ADP-ribose) polymerase in MDA-MB-231 cells. Notably, immunoprecipitation revealed that LA disturbed the direct binding of AKT and FOXM1 in MDA-MB-231 cells. Overall, these findings suggest that LA-induced apoptosis is mediated via activation of AMPK and inhibition of AKT/FOXM1 signaling pathway.
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Affiliation(s)
- Jae Hee Lee
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, South Korea
| | - Hyo-Jung Lee
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, South Korea
| | - Deok Yong Sim
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, South Korea
| | - Ji Hoon Jung
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, South Korea
| | - Ka Ram Kim
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, South Korea
| | - Sung-Hoon Kim
- College of Korean Medicine, Kyung Hee University, Seoul, 02447, South Korea
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15
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Lassiter DG, Nylén C, Sjögren RJO, Chibalin AV, Wallberg-Henriksson H, Näslund E, Krook A, Zierath JR. FAK tyrosine phosphorylation is regulated by AMPK and controls metabolism in human skeletal muscle. Diabetologia 2018; 61:424-432. [PMID: 29022062 PMCID: PMC6449061 DOI: 10.1007/s00125-017-4451-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 08/11/2017] [Indexed: 01/28/2023]
Abstract
AIMS/HYPOTHESIS Insulin-mediated signals and AMP-activated protein kinase (AMPK)-mediated signals are activated in response to physiological conditions that represent energy abundance and shortage, respectively. Focal adhesion kinase (FAK) is implicated in insulin signalling and cancer progression in various non-muscle cell types and plays a regulatory role during skeletal muscle differentiation. The role of FAK in skeletal muscle in relation to insulin stimulation or AMPK activation is unknown. We examined the effects of insulin or AMPK activation on FAK phosphorylation in human skeletal muscle and the direct role of FAK on glucose and lipid metabolism. We hypothesised that insulin treatment and AMPK activation would have opposing effects on FAK phosphorylation and that gene silencing of FAK would alter metabolism. METHODS Human muscle was treated with insulin or the AMPK-activating compound 5-aminoimadazole-4-carboxamide ribonucleotide (AICAR) to determine FAK phosphorylation and glucose transport. Primary human skeletal muscle cells were used to study the effects of insulin or AICAR treatment on FAK signalling during serum starvation, as well as to determine the metabolic consequences of silencing the FAK gene, PTK2. RESULTS AMPK activation reduced tyrosine phosphorylation of FAK in skeletal muscle. AICAR reduced p-FAKY397 in isolated human skeletal muscle and cultured myotubes. Insulin stimulation did not alter FAK phosphorylation. Serum starvation increased AMPK activation, as demonstrated by increased p-ACCS222, concomitant with reduced p-FAKY397. FAK signalling was reduced owing to serum starvation and AICAR treatment as demonstrated by reduced p-paxillinY118. Silencing PTK2 in primary human skeletal muscle cells increased palmitate oxidation and reduced glycogen synthesis. CONCLUSIONS/INTERPRETATION AMPK regulates FAK signalling in skeletal muscle. Moreover, siRNA-mediated FAK knockdown enhances lipid oxidation while impairing glycogen synthesis in skeletal muscle. Further exploration of the interaction between AMPK and FAK may lead to novel therapeutic strategies for diabetes and other chronic conditions associated with an altered metabolic homeostasis.
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Affiliation(s)
- David G Lassiter
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | - Carolina Nylén
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | - Rasmus J O Sjögren
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | - Alexander V Chibalin
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | | | - Erik Näslund
- Division of Surgery, Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Anna Krook
- Department of Physiology and Pharmacology, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
| | - Juleen R Zierath
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden.
- Department of Physiology and Pharmacology, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
- Section of Integrative Physiology, The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark.
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16
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Chung EJ, Do EJ, Kim SY, Cho EA, Kim DH, Pak S, Hwang SW, Lee HJ, Byeon JS, Ye BD, Yang DH, Park SH, Yang SK, Kim JH, Myung SJ. Combination of metformin and VSL#3 additively suppresses western-style diet induced colon cancer in mice. Eur J Pharmacol 2016; 794:1-7. [PMID: 27845068 DOI: 10.1016/j.ejphar.2016.11.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/31/2016] [Accepted: 11/07/2016] [Indexed: 02/07/2023]
Abstract
Western-style diet (WD) and dysbiosis are known to be associated with colonic inflammation, which contributes to carcinogenesis. Metformin (Met) exerts anti-inflammatory effects to induce AMP-activated protein kinase (AMPK), resulting in suppressed protein synthesis and reduced cell proliferation. Probiotic VSL#3 (V) modifies microbial composition. We investigated the chemopreventive mechanisms of Met and V in WD-induced colitis-associated colon carcinogenesis. Male BALB/c mice were randomly divided into five groups: a control diet (CD) group, WD group, WD+ Met (250mg/kg/day) group, WD+V (1.3 million bacteria/day) group, and WD+Met+V group. All mice were exposed to azoxymethane (10mg/kg) followed by 2% dextran sodium sulfate (DSS) for 7 days. Using HCT-116 human colon cancer cell line, expression of AMPK, extracellular signal-regulated kinase (ERK), cyclin D1, and Bcl-2 was investigated and cell cycle arrest was assessed. WD enhanced the severity of colitis and tumor growth compared with CD. The combination of Met and V significantly ameliorated colitis and tumor growth by inhibiting macrophage infiltration and maintaining epithelial integrity. In vitro assays showed that the combination therapy promoted late apoptosis by inhibiting cyclin D1 and Bcl-2 and activating pro-apoptotic ERK. A combination therapy with Met and V attenuates tumor growth in a mouse model of WD-induced colitic cancer, suggesting that this strategy could be useful for the chemoprevention of colon cancer.
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Affiliation(s)
- Eun-Ju Chung
- Health Screening & Promotion Center, Seoul, Republic of Korea
| | - Eun-Ju Do
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Sang-Yeob Kim
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea; Department of Medicine, University of Ulsan, College of Medicine, Seoul, Republic of Korea
| | - Eun A Cho
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Dong-Hee Kim
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Sehyung Pak
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Sung Wook Hwang
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hyo Jeong Lee
- Health Screening & Promotion Center, Seoul, Republic of Korea
| | - Jeong-Sik Byeon
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Byong Duk Ye
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Dong Hoon Yang
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sang Hyoung Park
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Suk-Kyun Yang
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jin-Ho Kim
- Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seung-Jae Myung
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea; Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
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Metformin mediated reversal of epithelial to mesenchymal transition is triggered by epigenetic changes in E-cadherin promoter. J Mol Med (Berl) 2016; 94:1397-1409. [DOI: 10.1007/s00109-016-1455-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 07/25/2016] [Accepted: 08/01/2016] [Indexed: 01/24/2023]
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18
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Jang HJ, Hong EM, Park SW, Byun HW, Koh DH, Choi MH, Kae SH, Lee J. Statin induces apoptosis of human colon cancer cells and downregulation of insulin-like growth factor 1 receptor via proapoptotic ERK activation. Oncol Lett 2016; 12:250-256. [PMID: 27347133 DOI: 10.3892/ol.2016.4569] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 04/08/2016] [Indexed: 12/20/2022] Open
Abstract
Insulin-like growth factor 1 (IGF-1) and IGF-1 receptor (IGF-1R) signaling plays an important role in tumor progression in patients with certain gastrointestinal tract cancers. In addition to lowering cholesterol in serum, statins have pleiotropic effects, including anti-oxidative, anti-inflammatory or anti-neoplastic effects. Therefore, the present study investigated whether statins could induce the apoptosis of colon cancer cells and regulate the expression of IGF-1R and its associated signaling pathways in the present study. It was demonstrated that simvastatin and pravastatin suppressed cell proliferation and induced cell death in human HT-29 cells, but simvastatin was more potent than pravastatin. Simvastatin induced apoptosis in a concentration-dependent manner. In addition, simvastatin suppressed the expression of IGF-1R and inhibited the activity of phosphorylated-extracellular signal-regulated kinase (ERK)1/2 and phosphorylated-Akt activated by IGF-1. Simvastatin and IGF-1 each stimulated the activity of phosphorylated ERK1/2. However, simvastatin inhibited cell proliferation and IGF-1 stimulated cell proliferation. Mevalonic acid and PD98059 reversed the ERK activation and apoptosis induced by treatment with simvastatin. It was concluded that simvastatin induces the apoptosis of human colon cancer cells and inhibits IGF-1-induced ERK and Akt expression via the downregulation of IGF-1R expression and proapoptotic ERK activation. Simvastatin may be beneficial for the treatment of colon cancer. The present study suggested that statin may possess therapeutic potential for the treatment of colon cancer.
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Affiliation(s)
- Hyun Joo Jang
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Eun Mi Hong
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Se Woo Park
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Hyun Woo Byun
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Dong Hee Koh
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Min Ho Choi
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Sea Hyub Kae
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
| | - Jin Lee
- Division of Gastroenterology, Department of Internal Medicine, Dongtan Sacred Heart Hospital, Hallym University School of Medicine, Hwasung, Gyeonggi 445-170, Republic of Korea
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Fang JY, Li ZH, Li Q, Huang WS, Kang L, Wang JP. Resveratrol affects protein kinase C activity and promotes apoptosis in human colon carcinoma cells. Asian Pac J Cancer Prev 2016; 13:6017-22. [PMID: 23464396 DOI: 10.7314/apjcp.2012.13.12.6017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Resveratrol has been reported to have potential chemopreventive and apoptosis-inducing properties in a variety of tumor cell lines. OBJECTIVE In this study, to investigate the effects of resveratrol on protein kinase C (PKC) activity and apoptosis in human colon carcinoma cells, we used HT-29 cells and examined the PKCα and ERK1/2 signaling pathways. METHODS To test the effects of resveratrol on the growth of HT- 29 cells, the cells were exposed to varying concentrations and assessed with the the MTT cell-viability assay. Fluorescence-activated cell sorter (FACS) analysis was applied to determine the effects of resveratrol on cell apoptosis. Western blotting was performed to determine the protein levels of PKCα and ERK1/2. In inhibition experiments, HT-29 cells were treated with Go?6976 or PD98059 for 30 min, followed by exposure to 200 μM resveratrol for 72 h. RESULTS Resveratrol had a significant inhibitory effect on HT-29 cell growth. FACS revealed that resveratrol induced apoptosis. Western blotting showed that e phosphorylation of PKCα and ERK1/2 was significantly increased in response to resveratrol treatment. Pre-treatment with PKCα and ERK1/2 inhibitors (Go?6976 and PD98059) promoted apoptosis. CONCLUSION Resveratrol has significant anti-proliferative effects on the colon cancer cell line HT-29. The PKC- ERK1/2 signaling pathway can partially mediate resveratrol-induced apoptosis of HT-29 cells.
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Affiliation(s)
- Jie-Yu Fang
- Department of Anesthesia, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
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20
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Lee IJ, Lee CW, Lee JH. CaMKKβ-AMPKα2 signaling contributes to mitotic Golgi fragmentation and the G2/M transition in mammalian cells. Cell Cycle 2015; 14:598-611. [PMID: 25590814 DOI: 10.4161/15384101.2014.991557] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Before a cell enters mitosis, the Golgi apparatus undergoes extensive fragmentation. This is required for the correct partitioning of the Golgi apparatus into daughter cells, and inhibition of this process leads to cell cycle arrest in G2 phase. AMP-activated protein kinase (AMPK) plays critical roles in regulating growth and reprogramming metabolism. Recent studies have suggested that AMPK promotes mitotic progression and Golgi disassembly, and that this seems independent of the cellular energy status. However, the molecular mechanism underlying these events is not well understood. Here, we show that both treatment with compound C and depletion of AMPKα2 (but not AMPKα1) delays the G2/M transition in synchronized HeLa cells, as evidenced by flow cytometry and mitotic index analysis. Furthermore, knockdown of AMPKα2 specifically delays further fragmentation of isolated Golgi stacks. Interestingly, pAMPKα(Thr172) signals transiently appear in the perinuclear region of late G2/early prophase cells, partially co-localizing with the Golgi matrix protein, GM-130. These Golgi pAMPKα(Thr172) signals were also specifically abolished by AMPKα2 knockdown, indicating specific spatio-temporal activation of AMPKα2 at Golgi complex during late G2/early prophases. We also found that the specific CaMKKβ inhibitor, STO-609, reduces the pAMPKα (Thr172) signals in the perinuclear region of G2 phase cells and delays mitotic Golgi fragmentation. Taken together, these data suggest that AMPKα2 is the major catalytic subunit of AMPKα which regulates Golgi fragmentation and G2/M transition, and that the CaMKKβ activates AMPKα2 during late G2 phase.
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Affiliation(s)
- In Jeong Lee
- a Department of Biochemistry and Molecular Biology ; Ajou University School of Medicine ; Suwon , Korea
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21
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Han J, Zhang L, Guo H, Wysham WZ, Roque DR, Willson AK, Sheng X, Zhou C, Bae-Jump VL. Glucose promotes cell proliferation, glucose uptake and invasion in endometrial cancer cells via AMPK/mTOR/S6 and MAPK signaling. Gynecol Oncol 2015; 138:668-75. [PMID: 26135947 DOI: 10.1016/j.ygyno.2015.06.036] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 06/23/2015] [Accepted: 06/24/2015] [Indexed: 12/17/2022]
Abstract
OBJECTIVES Obesity and diabetes are well-known risk factors for the development of endometrial cancer. A high rate of aerobic glycolysis represents a key mechanism by which endometrial cancer cells consume glucose as its primary energy source. The up-regulated glycolytic pathway is a common therapeutic target whose inhibition has implications for anti-tumor activity in cancer cells. This study aimed to investigate the effect of various concentrations of glucose on cell proliferation in endometrial cancer. METHODS ECC-1 and Ishikawa cells were treated with low glucose (1mM), normal glucose (5mM) and high glucose (25mM), and cytotoxicity, apoptosis, cell cycle, adhesion/invasion, and changes of AMPK/mTOR/S6 and MAPK pathways were evaluated. RESULTS Our results revealed that high glucose increased cell growth and clonogenicity in two endometrial cancer cell lines in a dose dependent manner. Low glucose induced the activity of cleaved caspase 3 and caused cell cycle G1 arrest. High glucose increased the ability of adhesion and invasion by decreasing E-cadherin and increasing Snail expression. In addition, high glucose increased glucose uptake and glycolytic activity through modulating the AMPK/mTOR/S6 and MAPK pathways. CONCLUSIONS Our findings suggest that glucose stimulated cell proliferation through multiple complex signaling pathways. Targeting glucose metabolism may be a promising therapeutic strategy in the treatment of endometrial cancer.
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Affiliation(s)
- Jianjun Han
- Department of Surgical Oncology, Shandong Cancer Hospital and Institute, Jinan, China; Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lu Zhang
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; School of Medicine and Life Sciences, University of Jinan, Shandong Academy of Medical Sciences, China; Department of Gynecologic Oncology, Shandong Cancer Hospital and Institute, Jinan, China
| | - Hui Guo
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; School of Medicine and Life Sciences, University of Jinan, Shandong Academy of Medical Sciences, China; Department of Gynecologic Oncology, Shandong Cancer Hospital and Institute, Jinan, China
| | - Weiya Z Wysham
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Dario R Roque
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Adam K Willson
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Xiugui Sheng
- Department of Gynecologic Oncology, Shandong Cancer Hospital and Institute, Jinan, China
| | - Chunxiao Zhou
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Victoria L Bae-Jump
- Division of Gynecologic Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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22
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Yen CY, Chiang WF, Liu SY, Lin CC, Liao KA, Lin CY, Hsieh WF, Cheng YC, Hsu KC, Lin PY, Chen TC, Lee IL, Lin MH, Liu YC. Impacts of autophagy-inducing ingredient of areca nut on tumor cells. PLoS One 2015; 10:e0128011. [PMID: 26017803 PMCID: PMC4445909 DOI: 10.1371/journal.pone.0128011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 04/21/2015] [Indexed: 12/17/2022] Open
Abstract
Areca nut (AN) is a popular carcinogen used by about 0.6-1.2 billion people worldwide. Although AN contains apoptosis-inducing ingredients, we previously demonstrated that both AN extract (ANE) and its 30-100 kDa fraction (ANE 30-100K) predominantly induce autophagic cell death in both normal and malignant cells. In this study, we further explored the action mechanism of ANE 30-100K-induced autophagy (AIA) in Jurkat T lymphocytes and carcinoma cell lines including OECM-1 (mouth), CE81T/VGH (esophagus), SCC25 (tongue), and SCC-15 (tongue). The results showed that chemical- and small hairpin RNA (shRNA)-mediated inhibition of AMP-activated protein kinase (AMPK) resulted in the attenuation of AIA in Jurkat T but not in OECM-1 cells. Knockdown of Atg5 and Beclin 1 expressions ameliorated AIA in OECM-1/CE81T/VGH/Jurkat T and OECM-1/SCC25/SCC-15, respectively. Furthermore, ANE 30-100K could activate caspase-3 after inhibition of Beclin 1 expression in OECM-1/SCC25/SCC15 cells. Meanwhile, AMPK was demonstrated to be the upstream activator of the extracellular-regulated kinase (ERK) in Jurkat T cells, and inhibition of MEK attenuated AIA in Jurkat T/OECM-1/CE81T/VGH cells. Finally, we also found that multiple myeloma RPMI8226, lymphoma U937, and SCC15 cells survived from long-term non-cytotoxic ANE 30-100K treatment exhibited stronger resistance against serum deprivation through upregulated autophagy. Collectively, our studies indicate that Beclin-1 and Atg5 but not AMPK are commonly required for AIA, and MEK/ERK pathway is involved in AIA. Meanwhile, it is also suggested that long-term AN usage might increase the resistance of survived tumor cells against serum-limited conditions.
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Affiliation(s)
- Ching-Yu Yen
- Department of Dentistry, Taipei Medical University, Taipei, Taiwan
- Department of Dentistry, National Defense Medical Center, Taipei, Taiwan
- Oral and Maxillofacial Surgery Section, Chi Mei Medical Center, Tainan, Taiwan
| | - Wei-Fan Chiang
- Oral and Maxillofacial Surgery Section, Chi Mei Hospital, Liouying, Taiwan
- School of Dentistry, National Yang-Ming University, Taipei, Taiwan
| | - Shyun-Yeu Liu
- Department of Dentistry, Taipei Medical University, Taipei, Taiwan
- Department of Dentistry, National Defense Medical Center, Taipei, Taiwan
- Oral and Maxillofacial Surgery Section, Chi Mei Medical Center, Tainan, Taiwan
| | - Chung-Chih Lin
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Kuo-An Liao
- Oral and Maxillofacial Surgery Section, Chi Mei Hospital, Liouying, Taiwan
| | - Che-Yi Lin
- Oral and Maxillofacial Surgery Section, Chi Mei Hospital, Liouying, Taiwan
| | - Wan-Fang Hsieh
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Yon-Chi Cheng
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Kai-Cheng Hsu
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Pin-Yen Lin
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Tai-Chi Chen
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - I-Ling Lee
- Oral and Maxillofacial Surgery Section, Chi Mei Hospital, Liouying, Taiwan
| | - Mei-Huei Lin
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
- * E-mail: (MHL); (YCL)
| | - Young-Chau Liu
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
- Division of Natural Science, College of Liberal Education, Shu-Te University, Kaohsiung, Taiwan
- * E-mail: (MHL); (YCL)
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Kim HS, Kim MJ, Lim J, Yang Y, Lee MS, Lim JS. NDRG2 overexpression enhances glucose deprivation-mediated apoptosis in breast cancer cells via inhibition of the LKB1-AMPK pathway. Genes Cancer 2014; 5:175-85. [PMID: 25061501 PMCID: PMC4104758 DOI: 10.18632/genesandcancer.17] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 06/25/2014] [Indexed: 02/07/2023] Open
Abstract
The newly identified tumor suppressor, N-myc downstream-regulated gene 2 (NDRG2), has been studied in various cancers because of its anticancer and antimetastasis effects. In this study, we examined the effect of NDRG2 expression on cell viability in MDA-MB-231 human breast cancer cells under conditions that are similar to the microenvironment of solid tumors, which include glucose deprivation. NDRG2 overexpression enhanced the pro-apoptotic effects of glucose deprivation. Glucose deprivation also induced the activation of AMP-activated protein kinase (AMPK), which plays a role in protecting tumor cells from metabolic stresses. NDRG2 overexpression strongly reduced glucose deprivation-induced AMPK phosphorylation and increased the cleavage of poly (ADP-ribose) polymerase (PARP), which indicated the induction of apoptosis. The expression of a constitutively active form of AMPK effectively blocked glucose deprivation-induced apoptosis in NDRG2-overexpressing MDA-MB-231 cells. Moreover, NDRG2 overexpression also enhanced the pro-apoptotic effects of 2-deoxyglucose (2-DG) or hypoxia, an inducer of metabolic stresses. Finally, we showed that LKB1 is an upstream kinase of AMPK that is involved in the inhibition of glucose deprivation-induced AMPK activity in NDRG2-overexpressing cells. Our findings collectively suggest that NDRG2 is a negative regulator of AMPK activity and functions as a sensitizer of glucose deprivation.
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Affiliation(s)
- Hak-Su Kim
- Department of Biological Sciences and the Research Center for Women's Diseases, Sookmyung Women's University, Seoul, Republic of Korea
| | - Myung-Jin Kim
- Department of Biological Sciences and the Research Center for Women's Diseases, Sookmyung Women's University, Seoul, Republic of Korea
| | - Jihyun Lim
- Department of Biological Sciences and the Research Center for Women's Diseases, Sookmyung Women's University, Seoul, Republic of Korea
| | - Young Yang
- Department of Biological Sciences and the Research Center for Women's Diseases, Sookmyung Women's University, Seoul, Republic of Korea
| | - Myeong-Sok Lee
- Department of Biological Sciences and the Research Center for Women's Diseases, Sookmyung Women's University, Seoul, Republic of Korea
| | - Jong-Seok Lim
- Department of Biological Sciences and the Research Center for Women's Diseases, Sookmyung Women's University, Seoul, Republic of Korea
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Kim WG, Choi HJ, Kim TY, Shong YK, Kim WB. The effect of 5-aminoimidazole-4-carboxamide-ribonucleoside was mediated by p38 mitogen activated protein kinase signaling pathway in FRO thyroid cancer cells. Korean J Intern Med 2014; 29:474-81. [PMID: 25045295 PMCID: PMC4101594 DOI: 10.3904/kjim.2014.29.4.474] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 07/23/2013] [Accepted: 09/01/2013] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND/AIMS 5'-Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a cellular energy sensor that monitors intracellular AMP/adenosine triphosphate (ATP) ratios and is a key regulator of the proliferation and survival of diverse malignant cell types. In the present study, we investigated the effect of activating AMPK by 5-aminoimidazole-4-carboxamide-ribonucleotide (AICAR) in thyroid cancer cells. METHODS We used FRO thyroid cancer cells harboring the BRAF(V600E) mutation to examine the effect of AICAR on cell proliferation and cell survival. We also evaluated the involvement of mitogen-activated protein kinase (MAPK) pathways in this effect. RESULTS We found that AICAR treatment promoted AMPK activation and suppressed cell proliferation and survival by inducing p21 accumulation and activating caspase-3. AICAR significantly induced activation of p38 MAPK, and pretreatment with SB203580, a specific inhibitor of the p38 MAPK pathway, partially but significantly rescued cell survival. Furthermore, small interfering RNA targeting AMPK-α1 abolished AICAR-induced activation of p38 MAPK, p21 accumulation, and activation of caspase-3. CONCLUSIONS Our findings demonstrate that AMPK activation using AICAR inhibited cell proliferation and survival by activating p38 MAPK and proapoptotic molecules in FRO thyroid cancer cells. These results suggest that the AMPK and p38 MAPK signaling pathways may be useful therapeutic targets to treat thyroid cancer.
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Affiliation(s)
- Won Gu Kim
- Division of Endocrinology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | | | - Tae Yong Kim
- Division of Endocrinology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Young Kee Shong
- Division of Endocrinology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Won Bae Kim
- Division of Endocrinology, Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Kim HS, Wannatung T, Lee S, Yang WK, Chung SH, Lim JS, Choe W, Kang I, Kim SS, Ha J. Quercetin enhances hypoxia-mediated apoptosis via direct inhibition of AMPK activity in HCT116 colon cancer. Apoptosis 2013; 17:938-49. [PMID: 22684842 DOI: 10.1007/s10495-012-0719-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Tumor hypoxia is considered the best validated target in clinical oncology because of its significant contribution to chemotherapy failure and drug resistance. As an approach to target hypoxia, we assessed the potential of quercetin, a flavonoid widely distributed in plants, as a anticancer agent under hypoxic conditions and examined its pharmacological mechanisms by primarily focusing on the role of AMP-activated protein kinase (AMPK). Quercetin significantly attenuated tumor growth in an HCT116 cancer xenograft in vivo model with a substantial reduction of AMPK activity. In a cell culture system, quercetin more dramatically induced apoptosis of HCT116 cancer cells under hypoxic conditions than normoxic conditions, and this was tightly associated with inhibition of hypoxia-induced AMPK activity. An in vitro kinase assay demonstrated that quercetin directly inhibits AMPK activity. Inhibition of AMPK by expressing a dominant-negative form resulted in an increase of apoptosis under hypoxia, and a constitutively active form of AMPK effectively blocked quercetin-induced apoptosis under hypoxia. Collectively, our data suggest that quercetin directly inhibits hypoxia-induced AMPK, which plays a protective role against hypoxia. Quercetin also reduced the activity of hypoxia-inducible factor-1 (HIF-1), a major transcription factor for adaptive cellular response to hypoxia. Moreover, quercetin sensitized HCT116 cancer cells to the anticancer drugs cisplatin and etoposide under hypoxic conditions. Our findings suggest that AMPK may serve as a novel target for overcoming tumor hypoxia-associated negative aspects.
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Affiliation(s)
- Hak-Su Kim
- Department of Biochemistry and Molecular Biology, Medical Research Center and Biomedical Science Institute, School of Medicine, Kyung Hee University, Seoul, 130-701, Korea
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Role of MKP-1 (DUSP1) in clozapine-induced effects on the ERK1/2 signaling pathway in the rat frontal cortex. Psychopharmacology (Berl) 2013; 230:425-37. [PMID: 23771439 DOI: 10.1007/s00213-013-3165-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Accepted: 05/30/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE Clozapine affects the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway in the brain, which plays an important role in its antipsychotic action. However, previous findings are inconsistent, and related molecular mechanisms require further clarification. OBJECTIVES Time- and dose-dependent effects of clozapine on the ERK1/2 pathway and its regulatory mechanism were investigated in rat frontal cortex. METHODS AND RESULTS At 15, 30, 60, and 120 min after intraperitoneal injection of clozapine (5, 10, and 20 mg/kg), changes in ERK1/2, its upstream canonical kinases (Raf1 and mitogen-activated protein kinase kinase 1/2 [MEK1/2]), and its downstream molecule (p90 ribosomal S6 kinase [p90RSK]) were investigated in rat frontal cortex. At 15 min, p-Raf1, p-MEK1/2, p-ERK1/2, and p-p90RSK all increased dose-dependently. At 30 min, p-ERK1/2 and p-p90RSK showed no significant changes, while dose-dependent increases in p-Raf1 and p-MEK1/2 were found. At 60 and 120 min, although p-ERK1/2 and p-p90RSK decreased, increases in p-Raf1 and p-MEK1/2 were maintained. A clozapine-induced reduction in ERK1/2 phosphorylation was evident at both tyrosine and threonine residues, suggesting the involvement of dual specificity phosphatases (DUSPs; mitogen-activated protein kinase phosphatases [MKPs]). mRNA expression of seven Dusps that can dephosphorylate ERK1/2 were examined; Mkp-1 (Dusp1) mRNA increased following clozapine treatment. Moreover, MKP-1 protein and phosphatase activity increased, and binding of MKP-1 to ERK1/2 was also upregulated by clozapine administration. CONCLUSIONS In rat frontal cortex, clozapine regulates ERK1/2 phosphorylation via MKP-1, which induces uncoupling between Raf1-MEK1/2 and ERK1/2-p90RSK activity. These findings suggest an important role of MKP-1 in the mechanism of action of clozapine.
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Deslauriers J, Desmarais C, Sarret P, Grignon S. Implication of the ERK/MAPK pathway in antipsychotics-induced dopamine D2 receptor upregulation and in the preventive effects of (±)-α-lipoic acid in SH-SY5Y neuroblastoma cells. J Mol Neurosci 2013; 52:378-83. [PMID: 24203573 DOI: 10.1007/s12031-013-0158-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 10/21/2013] [Indexed: 11/29/2022]
Abstract
Chronic administration of antipsychotics (APs) has been associated with dopamine D2 receptor (D2R) upregulation and tardive dyskinesia. We previously showed that haloperidol, a first-generation AP, exerted a more robust increase in D2R expression than amisulpride, a second-generation AP and that (±)-α-lipoic acid pre-treatment reversed the AP-induced D2R upregulation. We also demonstrated that the Akt/GSK-3β/β-catenin pathway is involved in the control of D2R expression levels, but is unlikely implicated in the preventive effects of (±)-α-lipoic acid since co-treatment with haloperidol and (±)-α-lipoic acid exerts synergistic effects on Akt/GSK-3β activation. These findings led us to examine whether the ERK/MAPK signaling pathway may be involved in D2R upregulation elicited by APs, and in its reversal by (±)-α-lipoic acid, in SH-SY5Y human neuroblastoma cells. Our results revealed that haloperidol, in parallel with an elevation in D2R mRNA levels, induced a larger increase of ERK (p42/p44) phosphorylation than amisulpride. Pre-treatment with the selective ERK inhibitor U0126 attenuated haloperidol-induced increase in D2R upregulation. Furthermore, (±)-α-lipoic acid prevented AP-induced ERK activation. These results show that (1) the ERK/MAPK pathway is involved in haloperidol-induced D2R upregulation; (2) the preventive effect of (±)-α-lipoic acid on haloperidol-induced D2R upregulation is in part mediated by an ERK/MAPK-dependent signaling cascade. Taken together, our data suggest that (±)-α-lipoic acid exerts synergistic effects with haloperidol on the Akt/GSK-3β pathway, potentially involved in the therapeutic effects of APs, and antagonism of ERK activation and D2R upregulation, potentially involved in tardive dyskinesia and treatment resistance.
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Affiliation(s)
- Jessica Deslauriers
- Department of Physiology and Biophysics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 12e avenue Nord, Sherbrooke, QC, Canada, J1H 5N4
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Lin CF, Young KC, Bai CH, Yu BC, Ma CT, Chien YC, Su HC, Wang HY, Liao CS, Lai HW, Tsao CW. Blockade of reactive oxygen species and Akt activation is critical for anti-inflammation and growth inhibition of metformin in phosphatase and tensin homolog-deficient RAW264.7 cells. Immunopharmacol Immunotoxicol 2013; 35:669-77. [PMID: 24053326 DOI: 10.3109/08923973.2013.837059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
CONTEXT Metformin is widely used for treatment of type 2 diabetes and has a potential application on the treatment of inflammation and cancer. Phosphatase and tensin homolog (PTEN) plays a critical role in cancer cell growth and inflammation; however, precise mechanisms remain unclear. OBJECTIVE We aimed to investigate the possible mechanisms of how PTEN regulates metformin against cell growth and inflammation. MATERIALS AND METHODS We established PTEN knockdown in RAW264.7 murine macrophages (shPTEN cells) to detect inflammatory mediators using commercial kits, production of reactive oxygen species (ROS) by flow cytometry, cell growth by MTT assay and phosphorylated levels of signal molecules by western blot. RESULTS The shPTEN cells had a significant large amount of inflammatory mediators, such as inducible nitric oxide synthase (iNOS)/nitric oxide (NO) and cyclooxygenase-2 (COX-2)/prostaglandin E(2) (PGE(2)); and also elevated the production of ROS and increased cell proliferation. These effects were accompanied with the activation of Akt and p38 mitogen-activated protein kinase (MAPK), and the inactivation of an AMP-activated protein kinase (AMPK) activator and extracellular signal-regulated kinase 1/2. Pretreatment with metformin not only blocked these inflammatory mediators, but also caused growth inhibition induced by significant apoptosis. Furthermore, inactivation of Akt, blockade of ROS generation and independence of activations of AMPK and MAPK by metformin were also observed. CONCLUSION Macrophages with PTEN deficiency developed a continuous inflammatory microenvironment, which further aggravated tumor cell growth. Moreover, metformin affected PTEN-deficient cells dependent of inhibition of ROS production and Akt activation against enlarged inflammatory mediators and/or cell growth in shPTEN cells.
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Kim JG, Lee SJ, Chae YS, Kang BW, Lee YJ, Oh SY, Kim MC, Kim KH, Kim SJ. Association between phosphorylated AMP-activated protein kinase and MAPK3/1 expression and prognosis for patients with gastric cancer. Oncology 2013; 85:78-85. [PMID: 23860205 DOI: 10.1159/000351234] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 04/02/2013] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Phosphorylated AMP-activated protein kinase (pAMPK) plays a central role in cellular metabolic sensing and energy balance homeostasis, and interacts with various pathways [e.g., TP53, mTOR, NUAK2 (sucrose nonfermenting-like kinase), MAPK3/1 (ERK) and PDK]. Therefore, the present study analyzed the expression of pAMPK, NUAK2, MAPK3/1 and PDK-1 and their effect on the survival of patients with resected gastric cancer. METHODS A total of 621 patients with gastric adenocarcinoma surgically resected with curative intent were enrolled in the study. Immunohistochemical staining for pAMPK, NUAK2, MAPK3/1 and PDK-1 was performed using tissue microarrays of surgical specimens of gastric cancer tissue. RESULTS Positive pAMPK, NUAK2, MAPK3/1 and PDK-1 expression was observed in 379 (61.0%), 257 (41.4%), 327 (52.7%) and 67 (10.8%) cases, respectively. Multivariate survival analysis showed a significantly better survival for the patients with positive pAMPK or MAPK3/1 expression than for the patients with a negative expression [pAMPK: disease-free survival (DFS), hazard ratio (HR) = 0.750, 95% confidence interval (CI) = 0.568-0.970, p = 0.030; MAPK3/1: DFS, HR = 0.692, 95% CI = 0.720-0.974, p = 0.021), while NUAK2 or PDK-1 expression had no effect on survival. CONCLUSION pAMPK or MAPK3/1 expression was found to be an independent prognostic marker for patients with resected gastric cancer.
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Affiliation(s)
- Jong Gwang Kim
- Center for Oncology/Hematology, Kyungpook National University Medical Center, Kyungpook National University School of Medicine, Daegu, Korea.
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Borgdorff V, Rix U, Winter GE, Gridling M, Müller AC, Breitwieser FP, Wagner C, Colinge J, Bennett KL, Superti-Furga G, Wagner SN. A chemical biology approach identifies AMPK as a modulator of melanoma oncogene MITF. Oncogene 2013; 33:2531-9. [DOI: 10.1038/onc.2013.185] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 01/29/2013] [Accepted: 04/12/2013] [Indexed: 12/12/2022]
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Abstract
Cytochrome P450-1A1 (CYP1A1) is an extrahepatic phase I metabolizing enzyme whose expression is suppressed under physiologic conditions but can be induced by substrates via the aryl hydrocarbon receptor (AhR). Recent studies have shown that the majority of breast cancer tumors constitutively express CYP1A1. These findings led us to test the hypothesis that CYP1A1 promotes breast cancer progression by evaluating the effects of CYP1A1 knockdown on the proliferation and survival of the MCF7 and MDA-MB-231 lines. Independently of estrogen receptor status, CYP1A1 knockdown decreased colony formation, decreased cell proliferation, blocked the cell cycle at G0-G1 associated with reduction of cyclin D1, and increased apoptosis associated with reduction of survivin. CYP1A1 knockdown markedly increased phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphorylation of AKT, extracellular signal-regulated kinases 1 and 2 (ERK1/2), and 70-kDa ribosomal protein S6 kinase (P70S6K). AMPK inhibition by compound C partially abrogated the proapoptotic effects of CYP1A1 knockdown, suggesting that effects of CYP1A1 knockdown are mediated in part through AMPK signaling. Consistent with CYP1A1 knockdown, pharmacologic reduction of CYP1A1 levels by the phytopolyphenol carnosol also correlated with impaired proliferation and induced AMPK phosphorylation. These results indicate that reduction of basal CYP1A1 expression is critical for inhibition of proliferation, which is not affected by α-naphthoflavone-mediated inhibition of CYP1A1 activity nor modulated by AhR silencing. This study supports the notion that CYP1A1 promotes breast cancer proliferation and survival, at least in part, through suppression of AMPK signaling and that reduction of CYP1A1 levels is a potential strategy for breast cancer therapeutics.
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Affiliation(s)
- Mariangellys Rodriguez
- Division of Hematology, Oncology and Transplantation, Department of Medicine, The Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Brown KA, Samarajeewa NU, Simpson ER. Endocrine-related cancers and the role of AMPK. Mol Cell Endocrinol 2013; 366:170-9. [PMID: 22801104 DOI: 10.1016/j.mce.2012.06.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 04/06/2012] [Accepted: 06/21/2012] [Indexed: 01/27/2023]
Abstract
AMP-activated protein kinase (AMPK) is a master regulator of energy homeostasis involved in the regulation of a number of physiological processes including β-oxidation of fatty acids, lipogenesis, protein and cholesterol synthesis, as well as cell cycle inhibition and apoptosis. Important changes to these processes are known to occur in cancer due to changes in AMPK activity within cancer cells and in the periphery. This review aims to present findings relating to the role and regulation of AMPK in endocrine-related cancers. Obesity is a known risk factor for many types of cancers and a number of endocrine factors, including adipokines and steroid hormones, are regulated by and regulate AMPK. A clear role for AMPK in breast cancer is evident from the already impressive body of work published to date. However, information pertaining to its role in prostate cancer is still contentious, and future work should unravel the intricacies behind its role to inhibit, in some cases, and stimulate cancer growth in others. This review also presents data relating to the role of AMPK in cancers of the endometrium, ovary and colon, and discusses the possible use of AMPK-activating drugs including metformin for the treatment of all endocrine-related cancers.
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Affiliation(s)
- Kristy A Brown
- Metabolism and Cancer Laboratory, Prince Henry's Institute, Clayton 3168, Australia.
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Altman BJ, Rathmell JC. Metabolic stress in autophagy and cell death pathways. Cold Spring Harb Perspect Biol 2012; 4:a008763. [PMID: 22952396 DOI: 10.1101/cshperspect.a008763] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Growth factors and oncogenic kinases play important roles in stimulating cell growth during development and transformation. These processes have significant energetic and synthetic requirements and it is apparent that a central function of growth signals is to promote glucose metabolism to support these demands. Because metabolic pathways represent a fundamental aspect of cell proliferation and survival, there is considerable interest in targeting metabolism as a means to eliminate cancer. A challenge, however, is that molecular links between metabolic stress and cell death are poorly understood. Here we review current literature on how cells cope with metabolic stress and how autophagy, apoptosis, and necrosis are tightly linked to cell metabolism. Ultimately, understanding of the interplay between nutrients, autophagy, and cell death will be a key component in development of new treatment strategies to exploit the altered metabolism of cancer cells.
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Affiliation(s)
- Brian J Altman
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina 27710, USA
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Abstract
Cancer cell proliferation and progression require sufficient supplies of nutrients including carbon sources, nitrogen sources, and molecular oxygen. Particularly, carbon sources and molecular oxygen are critical for the generation of ATP and building blocks, and for the maintenance of intracellular redox status. However, solid tumors frequently outgrow the blood supply, resulting in nutrient insufficiency. Accordingly, cancer cell metabolism shows aberrant biochemical features that are consequences of oncogenic signaling and adaptation. Those adaptive metabolism features, including the Warburg effect and addiction to glutamine, may form the biochemical basis for resistance to chemotherapy and radiation. A better understanding of the regulatory mechanisms that link the signaling pathways to adaptive metabolic reprogramming may identify novel biomarkers for drug development. In this review, we focus on the regulation of carbon source utilization at a cellular level, emphasizing its relevance to proliferative biosynthesis in cancer cells. We summarize the essential needs of proliferating cells and the metabolic features of glucose, lipids, and glutamine, and we review the roles of transcription regulators (i.e., HIF-1, c-Myc, and p53) and two major oncogenic signaling pathways (i.e., PI3K-Akt and MAPK) in regulating the utilization of carbon sources. Finally, the effects of glucose on cell proliferation and perspective from both biochemical and cellular angles are discussed.
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Affiliation(s)
- Chengqian Yin
- Department of Biology, College of Arts and Sciences, Drexel University, Philadelphia, Pennsylvania, USA
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Modulation of AT-1R/AMPK-MAPK cascade plays crucial role for the pathogenesis of diabetic cardiomyopathy in transgenic type 2 diabetic (Spontaneous Diabetic Torii) rats. Biochem Pharmacol 2012; 83:653-60. [DOI: 10.1016/j.bcp.2011.11.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/19/2011] [Accepted: 11/21/2011] [Indexed: 02/08/2023]
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Nelson LE, Valentine RJ, Cacicedo JM, Gauthier MS, Ido Y, Ruderman NB. A novel inverse relationship between metformin-triggered AMPK-SIRT1 signaling and p53 protein abundance in high glucose-exposed HepG2 cells. Am J Physiol Cell Physiol 2012; 303:C4-C13. [PMID: 22378745 DOI: 10.1152/ajpcell.00296.2011] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
AMP-activated protein kinase (AMPK) and the NAD(+)-dependent histone/protein deacetylase sirtuin 1 (SIRT1) are metabolic sensors that can increase each other's activity. They are also both activated by the antidiabetic drug metformin and downregulated in the liver under conditions of nutrient excess (e.g., hyperglycemia, high-fat diet, obesity). In these situations, the abundance of the tumor suppressor p53 is increased; however, the relevance of this to the changes in AMPK and SIRT1 is not known. In the present study we investigated this question in HepG2 cells under high glucose conditions. Metformin induced activation of AMPK and SIRT1 and decreased p53 protein abundance. It also decreased triglyceride accumulation and cytosolic oxidative stress (a trigger for p53 accumulation) and increased the deacetylation of p53 at a SIRT1-targeted site. The decrease in p53 abundance caused by metformin was abolished by inhibition of murine double minute 2 (MDM2), a ubiquitin ligase that mediates p53 degradation, as well as by overexpression of a dominant-negative AMPK or a shRNA-mediated knockdown of SIRT1. In addition, overexpression of p53 decreased SIRT1 gene expression and protein abundance, as well as AMPK activity in metformin-treated cells. It also diminished the triglyceride-lowering action of metformin, an effect that was rescued by incubation with the SIRT1 activator SRT2183. Collectively, these findings suggest the existence of a novel reciprocal interaction between AMPK/SIRT1 and p53 that may have implications for the pathogenesis and treatment of metabolic diseases.
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Affiliation(s)
- Lauren E Nelson
- Endocrinology, Diabetes, and Nutrition Section, Department of Medicine, Boston University School of Medicine, Massachusetts, USA
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Berberine-induced AMPK activation inhibits the metastatic potential of melanoma cells via reduction of ERK activity and COX-2 protein expression. Biochem Pharmacol 2012; 83:385-94. [DOI: 10.1016/j.bcp.2011.11.008] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 11/05/2011] [Accepted: 11/09/2011] [Indexed: 12/25/2022]
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Chen MB, Shen WX, Yang Y, Wu XY, Gu JH, Lu PH. Activation of AMP-activated protein kinase is involved in vincristine-induced cell apoptosis in B16 melanoma cell. J Cell Physiol 2011; 226:1915-25. [PMID: 21506122 DOI: 10.1002/jcp.22522] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The molecular basis for induction of apoptosis in melanoma cells by vincristine remains unknown. Here we tested the potential involvement of AMP-activated protein kinase (AMPK) in this process. We found for the first time that vincristine induces AMPK activation (AMPKα, Thr 172) and Acetyl-CoA carboxylase (ACC, Ser 79) (a downstream molecular target of AMPK) phosphorylation in cultured melanoma cells in vitro. Reactive oxygen species (ROS) dependent LKB1 activation serves as the upstream signal for AMPK activation. AMPK inhibitor (compound C) or AMPKα siRNA knockdown inhibits vincristine induced B16 melanoma cell apoptosis, while AMPK activator 5-aminoimidazole-4-carboxamide-1-β-riboside (AICAR) enhances it. AMPK activation is involved in vincristine induced p53 phosphorylation and stabilization, the latter is known to mediate melanoma cell apoptosis. Further, activation of AMPK by vincristine inhibits mTOR Complex 1 (mTORC1) in B16 melanoma cells, which serves as another important mechanism to induce melanoma cell apoptosis. Our study provides new insights into understanding the cellular and molecular mechanisms of vincristine induced cancer cell death/apoptosis. We suggest that combining AMPK activator AICAR with vincristine may have potential to be used as a new therapeutic intervention against melanoma.
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Affiliation(s)
- Min-Bin Chen
- Department of Medical Oncology, Kunshan First People's Hospital Affiliated to Jiangsu University, Kunshan, Jiangsu Province, China
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Abstract
Metastasis is characterized by the ability of cancer cells to invade into adjacent tissue, intravasate into blood or lymphatic vessels, and extravasate into a distant tissue. Metastatic disease is primarily responsible for the low 5-year survival rate of non-small cell lung cancer (NSCLC), and therefore, an understanding of the molecular mechanisms that regulate NSCLC metastasis is clearly warranted. The serine/threonine kinase and tumor suppressor LKB1 is mutated in 30% of NSCLC tumors, and recent evidence points to a prominent role in NSCLC metastasis. This review summarizes LKB1-dependent invasion pathways where compromised LKB1 function could promote NSCLC metastasis.
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Jeong JH, Kang JH, Hwang SL, Cho HJ, Park KK, Park YY, Chung IK, Chang HW, Kim CH, Min KS, Kim HD, Magae J, Kang SS, Chang YC. 4-O-methylascochlorin, methylated derivative of ascochlorin, stabilizes HIF-1α via AMPK activation. Biochem Biophys Res Commun 2011; 406:353-8. [PMID: 21329651 DOI: 10.1016/j.bbrc.2011.02.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 02/11/2011] [Indexed: 12/01/2022]
Abstract
Chemopreventive or anticancer agents induce cancer cells to apoptosis through the activation of adenosine AMP-activated protein kinase (AMPK), which plays a major role as energy sensors under ATP-deprived condition or ROS generation. In this study, we compared the effects of ascochlorin (ASC), from the fungus Ascochyta viciae, and its derivatives on AMPK activity. We also examined a regulatory mechanism for hypoxia-inducible factor-1α (HIF-1α) stabilization in response to 4-O-methylascochlorin (MAC). We found that AMPK activation was mainly involved with MAC, but not ASC and 4-O-carboxymethylascochlorin (AS-6), indicating that the substitution of 4-O-methyl group from 4-O-hydroxyl group of ASC is important in the activation of AMPK and the expression of HIF-1α. MAC-stabilized HIF-1α via AMPK activation triggered by lowering the intracellular ATP level, not by ROS generation, increases glucose uptake and the expression of vascular endothelial growth factor (VEGF) and glucose transporter 1 (GLUT-1), major target genes of HIF-1α. Moreover, MAC-induced AMPK activity suppressed survival factors, including mTOR and ERK1/2 or translational regulators, including p70S6K and 4E-BP1. Our data suggest that AMPK is a key determinant of MAC-induced HIF-1α expression in response to energy stress, further implying its involvement in MAC-induced apoptosis.
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Affiliation(s)
- Ji-Hak Jeong
- Research Institute of Biomedical Engineering and Department of Medicine, Catholic University of Daegu School of Medicine, Daegu 705-718, Republic of Korea
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Chen V, Shtivelman E. CC3/TIP30 regulates metabolic adaptation of tumor cells to glucose limitation. Cell Cycle 2010; 9:4941-53. [PMID: 21150275 DOI: 10.4161/cc.9.24.14230] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
CC3/TIP30 is a metastasis and tumor suppressor, with reduced or absent expression in a variety of aggressive tumors. Overexpression of CC3 in tumor cells predisposes them to apoptosis in response to different death signals. We found that silencing of CC3 expression does not increase apoptotic resistance of cells. However, it strongly improves survival of tumor cells in response to glucose limitation. HeLa cells with silenced CC3 survive long-term in low glucose, and, in comparison to control HeLa cells, show superior metabolic adaptation to glucose limitation. First, unlike the parental HeLa cells, HeLa with silenced CC3 activate and maintain high levels of mitochondrial respiration that is critical for their ability to thrive in low glucose. Second, silencing of CC3 leads to higher expression levels of mitochondrial proteins in respiration complexes when cells are continuously cultured in limiting glucose. Third, HeLa cells with silenced CC3 maintain higher levels of c-MYC and the M2 isoform of pyruvate kinase in low glucose, contributing to more efficient glycolysis. Fourth, HeLa cells with silenced CC3 fail to fully activate AMPK in response to glucose limitation. Inhibition of AMPK, either pharmacologic or via siRNA, protects control HeLa cells from death in low glucose. The metabolic flexibility acquired by cells after silencing of CC3 could be directly relevant to the development of metastatic and aggressive human tumors that frequently have low or absent expression of CC3.
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Mason EF, Rathmell JC. Cell metabolism: an essential link between cell growth and apoptosis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1813:645-54. [PMID: 20816705 DOI: 10.1016/j.bbamcr.2010.08.011] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 08/20/2010] [Accepted: 08/24/2010] [Indexed: 12/12/2022]
Abstract
Growth factor-stimulated or cancerous cells require sufficient nutrients to meet the metabolic demands of cell growth and division. If nutrients are insufficient, metabolic checkpoints are triggered that lead to cell cycle arrest and the activation of the intrinsic apoptotic cascade through a process dependent on the Bcl-2 family of proteins. Given the connections between metabolism and apoptosis, the notion of targeting metabolism to induce cell death in cancer cells has recently garnered much attention. However, the signaling pathways by which metabolic stresses induce apoptosis have not as of yet been fully elucidated. Thus, the best approach to this promising therapeutic avenue remains unclear. This review will discuss the intricate links between metabolism, growth, and intrinsic apoptosis and will consider ways in which manipulation of metabolism might be exploited to promote apoptotic cell death in cancer cells. This article is part of a Special Issue entitled Mitochondria: the deadly organelle.
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Affiliation(s)
- Emily F Mason
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
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Prognostic significance of AMP-activated protein kinase expression and modifying effect of MAPK3/1 in colorectal cancer. Br J Cancer 2010; 103:1025-33. [PMID: 20808308 PMCID: PMC2965861 DOI: 10.1038/sj.bjc.6605846] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AMP-activated protein kinase (AMPK, PRKA) has central roles in cellular metabolic sensing and energy balance homeostasis, and interacts with various pathways (e.g., TP53 (p53), FASN, MTOR and MAPK3/1 (ERK)). AMP-activated protein kinase activation is cytotoxic to cancer cells, supporting AMPK as a tumour suppressor and a potential therapeutic target. However, no study has examined its prognostic role in colorectal cancers. METHODS Among 718 colon and rectal cancers, phosphorylated AMPK (p-AMPK) and p-MAPK3/1 expression was detected in 409 and 202 tumours, respectively, by immunohistochemistry. Cox proportional hazards model was used to compute mortality hazard ratio (HR), adjusting for clinical and tumoral features, including microsatellite instability, CpG island methylator phenotype, LINE-1 methylation, and KRAS, BRAF and PIK3CA mutations. RESULTS Phosphorylated AMPK expression was not associated with survival among all patients. Notably, prognostic effect of p-AMPK significantly differed by p-MAPK3/1 status (P(interaction)=0.0017). Phosphorylated AMPK expression was associated with superior colorectal cancer-specific survival (adjusted HR 0.42; 95% confidence interval (CI), 0.24-0.74) among p-MAPK3/1-positive cases, but not among p-MAPK3/1-negative cases (adjusted HR 1.22; 95% CI: 0.85-1.75). CONCLUSION Phosphorylated AMPK expression in colorectal cancer is associated with superior prognosis among p-MAPK3/1-positive cases, but not among p-MAPK3/1-negative cases, suggesting a possible interaction between the AMPK and MAPK pathways influencing tumour behaviour.
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