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Zhu X, Zhou M, Liu G, Huang X, He W, Gou X, Jiang T. Autophagy activated by the c-Jun N-terminal kinase-mediated pathway protects human prostate cancer PC3 cells from celecoxib-induced apoptosis. Exp Ther Med 2017; 13:2348-2354. [PMID: 28565848 PMCID: PMC5443255 DOI: 10.3892/etm.2017.4287] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 02/03/2017] [Indexed: 12/23/2022] Open
Abstract
The aim of the present study was to investigate the role of autophagy in celecoxib-induced apoptosis in human hormone-insensitive prostate cancer cell line PC3 cells and to explore the underlying molecular mechanism leading to autophagic activation. A cell viability assay was applied to investigate the effect of various concentrations of celecoxib (0, 40, 60, 80, 100 and 120 µmol/l) on PC3 cells for 24 and 48 h, respectively. The 50% inhibitory concentration of celecoxib for 24 h was chosen for subsequent experiments. Annexin V-fluorescein isothiocyanate/propidium iodide double staining flow cytometry, as well as caspase 3 and poly (ADP-ribose) polymerase proteins detected by western blotting, were applied to analyze cellular apoptosis induced by celecoxib. Ultrastructural cellular changes observed by transmission electron microscopy and the level of LC-3 II and P62 detected by western blotting were used to determine the activation of autophagy. It was demonstrated that celecoxib induced apoptosis and activated autophagy in PC3 cells in a dose- and time-dependent manner. Furthermore, flow cytometry and western blotting were applied to elucidate whether the role of autophagy in celecoxib-induced apoptosis is protective or destructive. Blockade of autophagy markedly increased apoptosis, suggesting that celecoxib-activated autophagy was cytoprotective. Additionally, c-jun-N-terminal kinase (JNK) was demonstrated to have a role in autophagic activation, and suppression of JNK was able to reduce autophagy and increase apoptosis. In conclusion, the results of the present study indicate that celecoxib induces apoptosis in PC3 cells; however, celecoxib also activates JNK-mediated autophagy, which exerts cytoprotective effects in prostate cancer PC3 cells. Blockade of autophagy via the JNK-mediated pathway may provide a promising strategy for prostate cancer therapy.
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Affiliation(s)
- Xin Zhu
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Mi Zhou
- Department of Respiratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Guanyu Liu
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.,Department of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Xiaolong Huang
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.,Department of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Weiyang He
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Xin Gou
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Tao Jiang
- Department of Respiratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
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52
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Zhou H, Yuan M, Yu Q, Zhou X, Min W, Gao D. Autophagy regulation and its role in gastric cancer and colorectal cancer. Cancer Biomark 2017; 17:1-10. [PMID: 27314289 DOI: 10.3233/cbm-160613] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Autophagy is associated with the occurrence, development, cellular adaptation, progression, treatment and prognosis of gastric cancer (GC) and colorectal cancer (CRC). The effect of autophagy in these two cancers has attracted our attention. OBJECTIVE The aim of this study was to describe the functional and regulatory mechanisms associated with autophagy in GC and CRC. METHODS We reviewed recent publications describing the role of autophagy in GC and CRC, including the functional characteristics, clinical significance and regulatory mechanisms. RESULTS Autophagy plays context-dependent dual roles in the development and progression of GC and CRC. It can either promote tumor growth and cell survival or can contribute to tumor suppression and promote cell death. Both of these effects employ complex regulatory networks, such as those mediated by p53, PI3K/Akt/mTOR, Ras and microRNA. Among the cellular process associated with these pathways, autophagy is a potential target for anti-tumor therapy. CONCLUSION Autophagy is associated with both tumorigenic and protective effects in cancer. However, the role of autophagy in GC and CRC remains unclear. Although the translation of the basic science of autophagy into clinical practice is a long process, the modulation of autophagy as a potential therapeutic approach in GC and CRC merits further investigation.
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Affiliation(s)
- Huangyan Zhou
- Department of Pathogen Biology and Immunology, Medical College of Nanchang University, Nanchang, Jiangxi, China.,Jiangxi Academy of Medical Sciences, Nanchang, Jiangxi, China.,Institute of Immunotherapy, Nanchang University, Nanchang, Jiangxi, China
| | - Min Yuan
- Department of Neurology, Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Qiongfang Yu
- Department of Gastroenterology and Hepatology, Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Xiaoyan Zhou
- Department of Pathophysiology, Medical College of Nanchang University, Nanchang, Jiangxi, China
| | - Weiping Min
- Department of Pathogen Biology and Immunology, Medical College of Nanchang University, Nanchang, Jiangxi, China.,Jiangxi Academy of Medical Sciences, Nanchang, Jiangxi, China.,Institute of Immunotherapy, Nanchang University, Nanchang, Jiangxi, China
| | - Dian Gao
- Department of Pathogen Biology and Immunology, Medical College of Nanchang University, Nanchang, Jiangxi, China.,Jiangxi Academy of Medical Sciences, Nanchang, Jiangxi, China.,Institute of Immunotherapy, Nanchang University, Nanchang, Jiangxi, China
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Pantovic A, Bosnjak M, Arsikin K, Kosic M, Mandic M, Ristic B, Tosic J, Grujicic D, Isakovic A, Micic N, Trajkovic V, Harhaji-Trajkovic L. In vitro antiglioma action of indomethacin is mediated via AMP-activated protein kinase/mTOR complex 1 signalling pathway. Int J Biochem Cell Biol 2016; 83:84-96. [PMID: 27988363 DOI: 10.1016/j.biocel.2016.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 10/31/2016] [Accepted: 12/12/2016] [Indexed: 01/21/2023]
Abstract
We investigated the role of the intracellular energy-sensing AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway in the in vitro antiglioma effect of the cyclooxygenase (COX) inhibitor indomethacin. Indomethacin was more potent than COX inhibitors diclofenac, naproxen, and ketoprofen in reducing the viability of U251 human glioma cells. Antiglioma effect of the drug was associated with p21 increase and G2M cell cycle arrest, as well as with oxidative stress, mitochondrial depolarization, caspase activation, and the induction of apoptosis. Indomethacin increased the phosphorylation of AMPK and its targets Raptor and acetyl-CoA carboxylase (ACC), and reduced the phosphorylation of mTOR and mTOR complex 1 (mTORC1) substrates p70S6 kinase and PRAS40 (Ser183). AMPK knockdown by RNA interference, as well as the treatment with the mTORC1 activator leucine, prevented indomethacin-mediated mTORC1 inhibition and cytotoxic action, while AMPK activators metformin and AICAR mimicked the effects of the drug. AMPK activation by indomethacin correlated with intracellular ATP depletion and increase in AMP/ATP ratio, and was apparently independent of COX inhibition or the increase in intracellular calcium. Finally, the toxicity of indomethacin towards primary human glioma cells was associated with the activation of AMPK/Raptor/ACC and subsequent suppression of mTORC1/S6K. By demonstrating the involvement of AMPK/mTORC1 pathway in the antiglioma action of indomethacin, our results support its further exploration in glioma therapy.
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Affiliation(s)
| | - Mihajlo Bosnjak
- Institute of Histology and Embryology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Katarina Arsikin
- Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade, Serbia
| | - Milica Kosic
- Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade, Serbia
| | - Milos Mandic
- Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade, Serbia
| | - Biljana Ristic
- Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade, Serbia
| | - Jelena Tosic
- Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Danica Grujicic
- Clinic of Neurosurgery, Department of Neurooncology, Clinical Centre of Serbia, Belgrade, Serbia
| | - Aleksandra Isakovic
- Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Nikola Micic
- Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Vladimir Trajkovic
- Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade, Serbia.
| | - Ljubica Harhaji-Trajkovic
- Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Despot Stefan Blvd. 142, 11000 Belgrade, Serbia.
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Lu Y, Liu XF, Liu TR, Fan RF, Xu YC, Zhang XZ, Liu LL. Celecoxib exerts antitumor effects in HL-60 acute leukemia cells and inhibits autophagy by affecting lysosome function. Biomed Pharmacother 2016; 84:1551-1557. [DOI: 10.1016/j.biopha.2016.11.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 11/02/2016] [Accepted: 11/07/2016] [Indexed: 12/30/2022] Open
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55
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Enhanced cytotoxic activity of doxorubicin through the inhibition of autophagy in triple negative breast cancer cell line. Biochim Biophys Acta Gen Subj 2016; 1861:49-57. [PMID: 27842219 DOI: 10.1016/j.bbagen.2016.11.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 11/01/2016] [Accepted: 11/10/2016] [Indexed: 01/24/2023]
Abstract
BACKGROUND The outcome of triple negative breast cancer is still poor and requires improvement with better therapy options. Autophagy has recently been shown to play a role in anticancer drug resistance. Therefore, we investigated if the effectiveness of doxorubicin was augmented by the inhibition of autophagy. METHODS MDA-MB-231 was used as a model cell line for triple negative breast cancer and 3-methyladenine was used as an inhibitor of autophagy. Cells were treated with 0.46-1.84μM doxorubicin and 2.5-10μM 3-methyladenine for 48h. Cell death mode was examined with M30 and M65 ELISA assays. ROS level and LDH activity was examined and the cellular acidic compartment of cells was monitored by acridine orange staining. The expression of various autophagy and apoptosis related proteins/genes were evaluated with Western blotting and RT-qPCR respectively. RESULTS Synergism was observed between the compounds (CI value<1.0). RT-qPCR analysis revealed that the combination resulted in a down-regulation of autophagy-related genes. Moreover, the combination resulted in a different cell death modality, upregulating necroptosis-related genes. This suggests that the mode of cell death may switch from apoptosis to necroptosis, which is a more severe form of cell death, when autophagy is inhibited. These results were further confirmed at protein level by Western blotting. CONCLUSION Inhibition of autophagy seems to sensitize triple negative breast cancer cells to doxorubicin, warranting further in vivo studies for the proof of this concept. GENERAL SIGNIFICANCE Autophagy has a key role in drug resistance in MDA-MB-231 cells. Therefore combinatorial approaches may effectively overcome resistance.
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56
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Lu Y, Liu LL, Liu SS, Fang ZG, Zou Y, Deng XB, Long ZJ, Liu Q, Lin DJ. Celecoxib suppresses autophagy and enhances cytotoxicity of imatinib in imatinib-resistant chronic myeloid leukemia cells. J Transl Med 2016; 14:270. [PMID: 27645552 PMCID: PMC5029099 DOI: 10.1186/s12967-016-1012-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Accepted: 08/16/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Chronic myelogenous leukemia (CML) is a hematological stem cell disorder. Tyrosine kinase inhibitors (TKIs) are the standard treatments for CML, but a number of patients fail to respond effectively due to gene mutations. Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, has been shown to have anti-tumor effect on solid tumor whereas the anti-CML effect and its underlying mechanism have not been completely elucidated. METHODS The cytotoxic effects of celecoxib and/or imatinib were evaluated by MTT assay. Cell cycle distribution was examined by propidium iodide (PI) assay. Apoptosis or necrosis was analyzed by Annexin-V/PI, Hoechst 33342 staining and Western blot assays. Autophagy suppression effect of celecoxib was examined by Western blot and LysoTracker probe labelling. Lysosensor probe labelling was used to detect the effect of celecoxib on the lysosomal function. RESULTS In this study, we found that celecoxib had therapy efficacy in KBM5 and imatinib-resistant KBM5-T315I CML cell lines. Celecoxib caused significant cytotoxic effect in both cell lines, especially in KBM5-T315I cells exposed to celecoxib for 72 h. Moreover, celecoxib induced necrosis and apoptosis while inhibited autophagy in CML cell lines and patient samples. Furthermore, this study demonstrated that celecoxib prevented the autophagic flux by inhibiting lysosome function. Celecoxib was tested in combination with imatinib, demonstrating that celecoxib could strengthen the cytotoxicity of imatinib in imatinib-resistant CML cells. CONCLUSIONS These findings showed that celecoxib had therapy efficacy on CML cells. And it is first time to demonstrate that celecoxib is an autophagy suppresser and a combination of celecoxib and imatinib might be a promising new therapeutic strategy for imatinib-resistant CML cells.
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Affiliation(s)
- Ying Lu
- Department of Blood Transfusion, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Department of Hematology, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Ling-Ling Liu
- Department of Hematology, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Shou-Sheng Liu
- State Key Laboratory of Oncology in South China, Department of VIP Region, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Zhi-Gang Fang
- Department of Hematology, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yong Zou
- Department of Blood Transfusion, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xu-Bin Deng
- Cancer Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zi-Jie Long
- Department of Hematology, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Institute of Hematology, Sun Yat-sen University, Guangzhou, China
| | - Quentin Liu
- Department of Hematology, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Institute of Hematology, Sun Yat-sen University, Guangzhou, China
| | - Dong-Jun Lin
- Department of Blood Transfusion, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. .,Department of Hematology, the Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. .,Institute of Hematology, Sun Yat-sen University, Guangzhou, China.
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57
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Hwang KE, Kim YS, Jung JW, Kwon SJ, Park DS, Cha BK, Oh SH, Yoon KH, Jeong ET, Kim HR. Inhibition of autophagy potentiates pemetrexed and simvastatin-induced apoptotic cell death in malignant mesothelioma and non-small cell lung cancer cells. Oncotarget 2016; 6:29482-96. [PMID: 26334320 PMCID: PMC4745741 DOI: 10.18632/oncotarget.5022] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 08/10/2015] [Indexed: 12/21/2022] Open
Abstract
Pemetrexed, a multitarget antifolate used to treat malignant mesothelioma and non-small cell lung cancer (NSCLC), has been shown to stimulate autophagy. In this study, we determined whether autophagy could be induced by pemetrexed and simvastatin cotreatment in malignant mesothelioma and NSCLC cells. Furthermore, we determined whether inhibition of autophagy drives apoptosis in malignant mesothelioma and NSCLC cells. Malignant mesothelioma MSTO-211H and A549 NSCLC cells were treated with pemetrexed and simvastatin alone and in combination to evaluate their effect on autophagy and apoptosis. Cotreatment with pemetrexed and simvastatin induced greater caspase-dependent apoptosis and autophagy than either drug alone in malignant mesothelioma and NSCLC cells. 3-Methyladenine (3-MA), ATG5 siRNA, bafilomycin A, and E64D/pepstatin A enhanced the apoptotic potential of pemetrexed and simvastatin, whereas rapamycin and LY294002 attenuated their induction of caspase-dependent apoptosis. Our data indicate that pemetrexed and simvastatin cotreatment augmented apoptosis and autophagy in malignant mesothelioma and NSCLC cells. Inhibition of pemetrexed and simvastatin-induced autophagy was shown to enhance apoptosis, suggesting that this could be a novel therapeutic strategy against malignant mesothelioma and NSCLC.
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Affiliation(s)
- Ki-Eun Hwang
- Department of Internal Medicine, Institute of Wonkwang Medical Science, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
| | - Young-Suk Kim
- Department of Internal Medicine, Institute of Wonkwang Medical Science, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
| | - Jae-Wan Jung
- Department of Internal Medicine, Institute of Wonkwang Medical Science, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
| | - Su-Jin Kwon
- Department of Internal Medicine, Institute of Wonkwang Medical Science, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
| | - Do-Sim Park
- Department of Laboratory Medicine, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
| | - Byong-Ki Cha
- Department of Thoracic and Cardiovascular Surgery, Chonbuk National University Medical School, Jeonju, Jeonbuk, Korea
| | - Seon-Hee Oh
- Department of Natural Medical Sciences, College of Health Science, Chosun University, Seosuk-dong, Gwangju, Korea
| | - Kwon-Ha Yoon
- Department of Radiology, Wonkwang University School of Medicine, Iksan, Jeonbuk, Korea
| | - Eun-Taik Jeong
- Department of Internal Medicine, Institute of Wonkwang Medical Science, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
| | - Hak-Ryul Kim
- Department of Internal Medicine, Institute of Wonkwang Medical Science, Wonkwang University, School of Medicine, Iksan, Jeonbuk, Korea
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58
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Shi Q, Song X, Liu Z, Wang Y, Wang Y, Fu J, Su C, Xia X, Song E, Song Y. Quinones Derived from Polychlorinated Biphenyls Induce ROS-Dependent Autophagy by Evoking an Autophagic Flux and Inhibition of mTOR/p70S6k. Chem Res Toxicol 2016; 29:1160-71. [DOI: 10.1021/acs.chemrestox.6b00127] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Qiong Shi
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Xiufang Song
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Zixuan Liu
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Yawen Wang
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Yuxin Wang
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Juanli Fu
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Chuanyang Su
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Xiaomin Xia
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Erqun Song
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
| | - Yang Song
- Key Laboratory
of Luminescence
and Real-Time Analytical Chemistry (Southwest University), Ministry
of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People’s Republic of China
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BAO WENHUA, GU YIQI, TA LA, WANG KEREN, XU ZHELI. Induction of autophagy by the MG-132 proteasome inhibitor is associated with endoplasmic reticulum stress in MCF-7 cells. Mol Med Rep 2015; 13:796-804. [DOI: 10.3892/mmr.2015.4599] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 10/05/2015] [Indexed: 11/06/2022] Open
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60
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The interplay between GRP78 expression and Akt activation in human colon cancer cells under celecoxib treatment. Anticancer Drugs 2015. [PMID: 26225471 DOI: 10.1097/cad.0000000000000273] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
It has been reported previously that celecoxib shows antitumor effects in many types of cancers. Here, we detected its effects on DLD-1 and SW480 (two human colon cancer cell lines) and investigated the dynamic relationship between the 78-kDa glucose-regulatory protein (GRP78) and the phosphoinositide 3-kinase (PI3K)/Akt pathway. Gene expression was detected by real-time PCR and western blot analysis; the cytotoxicity was determined by the MTT assay and flow cytometry. First, the results showed that celecoxib induced cytotoxicity in a dose-dependent and time-dependent manner. Furthermore, we found the celecoxib-triggered unfolded protein response and the bidirectional regulation of Akt activation in both cell lines. Inhibiting the Akt activation by the PI3K inhibitor LY294002 markedly enhanced GRP78 expression. Besides, silencing the GRP78 expression regulated Akt activation in a time-dependent manner and increased the induction of the C/EBP homologous protein (CHOP) as well as considerably promoted celecoxib-induced apoptosis. In conclusion, these findings provide evidence that under the celecoxib treatment, GRP78 plays a protective role by modulating Akt activation and abrogating CHOP expression. However, Akt activation can provide a feedback loop to inhibit GRP78 expression. These studies can lead to novel therapeutic strategies for human colon cancer.
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Wang X, Zhang C, Yan X, Lan B, Wang J, Wei C, Cao X, Wang R, Yao J, Zhou T, Zhou M, Liu Q, Jiang B, Jiang P, Kesari S, Lin X, Guo F. A Novel Bioavailable BH3 Mimetic Efficiently Inhibits Colon Cancer via Cascade Effects of Mitochondria. Clin Cancer Res 2015; 22:1445-58. [PMID: 26515494 DOI: 10.1158/1078-0432.ccr-15-0732] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 09/15/2015] [Indexed: 11/16/2022]
Abstract
PURPOSE Gossypol and its analogs, through their ability to bind to and inactivate BH3 domain-containing antiapoptotic proteins, have been shown to inhibit the growth of various human cancer cells in culture and xenograft models. Here, we evaluated the antitumor efficacy of a novel gossypol derivative and BH3 mimetic ch282-5 (2-aminoethanesulfonic acid sodium-gossypolone) in colon cancer models. Several innovative combination strategies were also explored and elaborated. EXPERIMENTAL DESIGN Ch282-5 was synthesized by modifying the active aldehyde groups and R groups of gossypol according to a computer-aided drug design program. The stability of ch282-5 was examined by high-performance liquid chromatography, and cytotoxic effects of ch282-5 on colon cancer cells were assessed by MTS assay. Activation of mitochondrial apoptotic pathway by ch282-5 was evidenced with a series of molecular biology techniques. In vivo antitumor activity of ch282-5 and its combination with chloroquine, rapamycin, oxaliplatin, and ABT-263 was also evaluated in colon cancer xenograft models and experimental liver metastasis models. RESULTS Ch282-5 showed antiproliferative and pro-cell death activity against colon cancer cells both in vitro and in vivo, and the response to the drug correlated with inhibition of antiapoptotic Bcl-2 proteins, induction of mitochondria-dependent apoptotic pathway, and disruption of mitophagy and mTOR pathway. Ch282-5 also suppressed liver metastasis produced by intrasplenic injection of colon cancer cells. Furthermore, ch282-5 could potentiate the effectiveness of oxaliplatin and rescue ABT-263 efficacy by downregulation of Mcl-1 and elevation of platelet number. CONCLUSIONS These findings provide a rational basis for clinical investigation of this highly promising BH3 mimetic in colon cancer.
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Affiliation(s)
- Xuefeng Wang
- Laboratory of Tumor Targeted Therapy, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China. Institute of Health Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chen Zhang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substance, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, China
| | - Xiangming Yan
- Laboratory of Tumor Targeted Therapy, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Bin Lan
- Institute of Health Sciences, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China. Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jianyong Wang
- Laboratory of Tumor Targeted Therapy, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Chongyang Wei
- Laboratory of Tumor Targeted Therapy, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Xingxin Cao
- CAS Key Laboratory of Synthetic Chemistry of Natural Substance, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, China
| | - Renxiao Wang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substance, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, China
| | - Jianhua Yao
- CAS Key Laboratory of Synthetic Chemistry of Natural Substance, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, China
| | - Tao Zhou
- Academy of Life Science, Shanghai University, Shanghai, China
| | - Mi Zhou
- CAS Key Laboratory of Synthetic Chemistry of Natural Substance, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, China
| | - Qiaoling Liu
- Laboratory of Tumor Targeted Therapy, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Biao Jiang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substance, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, China
| | - Pengfei Jiang
- Department of Medicine and UC San Diego Moores Cancer Center, University of California-San Diego, La Jolla, California
| | - Santosh Kesari
- Department of Medicine and UC San Diego Moores Cancer Center, University of California-San Diego, La Jolla, California
| | - Xinjian Lin
- Department of Medicine and UC San Diego Moores Cancer Center, University of California-San Diego, La Jolla, California.
| | - Fang Guo
- Laboratory of Tumor Targeted Therapy, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China. Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, China.
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Targeted inhibition of p38MAPK-enhanced autophagy in SW620 cells resistant to photodynamic therapy-induced apoptosis. Lasers Med Sci 2015; 30:1967-75. [PMID: 26254783 DOI: 10.1007/s10103-015-1770-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 03/18/2015] [Indexed: 12/22/2022]
Abstract
Photodynamic therapy (PDT) is a promising and noninvasive treatment that can induce apoptosis, autophagy, or both depending on the cell phenotype. In this work, chlorin e6 (Ce6) was used to photosensitize human colorectal cancer SW620 cells. In cells, apparent autophagy and apoptosis with dependence on intracellular reactive oxygen species (ROS) generation were detected. p38MAPK activation followed by ROS generation might be a core component in Ce6 mediate PDT (Ce6-PDT)-induced autophagy and apoptosis signaling pathway. By using p38MAPK siRNA, the results showed a marked enhancement on cell apoptosis in Ce6-PDT with increased annexin (+) apoptotic cells, nuclear condensation, caspase-3, and PARP cleavage. Besides, impairment of p38MAPK also promoted the autophagic response to photodamage as indicated by conversion of LC3 and monodansyl cadaverine (MDC) labeling patterns. It appears that Ce6-PDT induced ROS production involving activation of p38MAPK, probably to prevent SW620 cells from photodamage. Moreover, autophagy inhibitor 3-methyladenine/bafilomycin A1 greatly aggravated Ce6-PDT-induced apoptosis in SW620 cells with knockdown of p38MAPK. Taken together, this study suggests that autophagy could represent a promising field in cancer treatment and p38MAPK may be a potential therapeutic target to enhance the efficacy on clinical evaluation for the treatment of colorectal cancer.
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Zaanan A, Okamoto K, Kawakami H, Khazaie K, Huang S, Sinicrope FA. The Mutant KRAS Gene Up-regulates BCL-XL Protein via STAT3 to Confer Apoptosis Resistance That Is Reversed by BIM Protein Induction and BCL-XL Antagonism. J Biol Chem 2015; 290:23838-49. [PMID: 26245900 DOI: 10.1074/jbc.m115.657833] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Indexed: 01/05/2023] Open
Abstract
In colorectal cancers with oncogenic GTPase Kras (KRAS) mutations, inhibition of downstream MEK/ERK signaling has shown limited efficacy, in part because of failure to induce a robust apoptotic response. We studied the mechanism of apoptosis resistance in mutant KRAS cells and sought to enhance the efficacy of a KRAS-specific MEK/ERK inhibitor, GDC-0623. GDC-0623 was shown to potently up-regulate BIM expression to a greater extent versus other MEK inhibitors in isogenic KRAS HCT116 and mutant KRAS SW620 colon cancer cells. ERK silencing enhanced BIM up-regulation by GDC-0623 that was due to its loss of phosphorylation at Ser(69), confirmed by a BIM-EL phosphorylation-defective mutant (S69G) that increased protein stability and blocked BIM induction. Despite BIM and BIK induction, the isogenic KRAS mutant versus wild-type cells remained resistant to GDC-0623-induced apoptosis, in part because of up-regulation of BCL-XL. KRAS knockdown by a doxycycline-inducible shRNA attenuated BCL-XL expression. BCL-XL knockdown sensitized KRAS mutant cells to GDC-0623-mediated apoptosis, as did the BH3 mimetic ABT-263. GDC-0623 plus ABT-263 induced a synergistic apoptosis by a mechanism that includes release of BIM from its sequestration by BCL-XL. Furthermore, mutant KRAS activated p-STAT3 (Tyr(705)) in the absence of IL-6 secretion, and STAT3 knockdown reduced BCL-XL mRNA and protein expression. These data suggest that BCL-XL up-regulation by STAT3 contributes to mutant KRAS-mediated apoptosis resistance. Such resistance can be overcome by potent BIM induction and concurrent BCL-XL antagonism to enable a synergistic apoptotic response.
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Affiliation(s)
- Aziz Zaanan
- From the Departments of Medicine and Oncology, Gastroenterology Research Unit, and the Mayo Clinic Cancer Center and
| | - Koichi Okamoto
- From the Departments of Medicine and Oncology, Gastroenterology Research Unit, and the Mayo Clinic Cancer Center and
| | - Hisato Kawakami
- From the Departments of Medicine and Oncology, Gastroenterology Research Unit, and the Mayo Clinic Cancer Center and
| | | | - Shengbing Huang
- From the Departments of Medicine and Oncology, Gastroenterology Research Unit, and the Mayo Clinic Cancer Center and
| | - Frank A Sinicrope
- From the Departments of Medicine and Oncology, Gastroenterology Research Unit, and the Mayo Clinic Cancer Center and
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Casasampere M, Ordoñez YF, Pou A, Casas J. Inhibitors of dihydroceramide desaturase 1: Therapeutic agents and pharmacological tools to decipher the role of dihydroceramides in cell biology. Chem Phys Lipids 2015; 197:33-44. [PMID: 26248324 DOI: 10.1016/j.chemphyslip.2015.07.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/29/2015] [Accepted: 07/31/2015] [Indexed: 02/07/2023]
Abstract
Dihydroceramide desaturase (Des1) is the last enzyme in the de novo synthesis of ceramides (Cer). It catalyzes the insertion of a double bond into dihydroceramides (dhCer) to convert them to Cer, both of which are further metabolized to more complex (dihydro) sphingolipids. For many years dhCer have received poor attention, mainly due to their supposed lack of biological activity. It was not until about ten years ago that the concept that dhCer might have regulatory roles in biology emerged for the first time. Since then, multiple publications have established that dhCer are implicated in a wide spectrum of biological processes. Physiological and pathophysiological functions of dhCer have been recently reviewed. In this review we will focus on the biochemical features of Des1 and on its inhibition by different compounds with presumably different modes of action.
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Affiliation(s)
- Mireia Casasampere
- Research Unit on BioActive Molecules, Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain
| | - Yadira F Ordoñez
- Research Unit on BioActive Molecules, Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain
| | - Ana Pou
- Research Unit on BioActive Molecules, Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain
| | - Josefina Casas
- Research Unit on BioActive Molecules, Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain.
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Xie SB, He XX, Yao SK. Matrine-induced autophagy regulated by p53 through AMP-activated protein kinase in human hepatoma cells. Int J Oncol 2015; 47:517-26. [PMID: 26034977 DOI: 10.3892/ijo.2015.3023] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 12/29/2014] [Indexed: 02/05/2023] Open
Abstract
Matrine, one of the main extract components of Sophora flavescens, has been shown to exhibit inhibitory effects on some tumors through autophagy. However, the mechanism underlying the effect of matrine remains unclear. The cultured human hepatocellular carcinoma cell line HepG2 and SMMC‑7721 were treated with matrine. Signal transduction and gene expression profile were determined. Matrine stimulated autophagy in SMMC‑7721 cells in a mammalian target of rapamycin (mTOR)-dependent manner, but in an mTOR-independent manner in HepG2 cells. Next, in HepG2 cells, autophagy induced by matrine was regulated by p53 inactivation through AMP-activated protein kinase (AMPK) signaling transduction, then AMPK suppression switched autophagy to apoptosis. Furthermore, the interferon (IFN)-inducible genes, including interferon α-inducible protein 27 (IFI27) and interferon induced transmembrane protein 1 (IFITM1), which are downstream effector of p53, might be modulated by matrine-induced autophagy. In addition, we found that the p53 protein isoforms, p53β, p53γ, ∆133p53, and ∆133p53γ, due to alternative splicing of intron 9, might be regulated by the p53-mediated autophagy. These results show that matrine induces autophagy in human hepatoma cells through a novel mechanism, which is p53/AMPK signaling pathway involvement in matrine-promoted autophagy.
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Affiliation(s)
- Shan-Bu Xie
- The Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Xing-Xing He
- The Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, P.R. China
| | - Shu-Kun Yao
- The Department of Gastroenterology, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, P.R. China
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Zhang D, Tang B, Xie X, Xiao YF, Yang SM, Zhang JW. The interplay between DNA repair and autophagy in cancer therapy. Cancer Biol Ther 2015; 16:1005-13. [PMID: 25985143 DOI: 10.1080/15384047.2015.1046022] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
DNA is the prime target of anticancer treatments. DNA damage triggers a series of signaling cascades promoting cellular survival, including DNA repair, cell cycle arrest, and autophagy. The elevated basal and/or stressful levels of both DNA repair and autophagy observed in tumor cells, in contrast to normal cells, have been identified as the most important drug-responsive programs that impact the outcome of anticancer therapy. The exact relationship between DNA repair and autophagy in cancer cells remains unclear. On one hand, autophagy has been shown to regulate some of the DNA repair proteins after DNA damage by maintaining the balance between their synthesis, stabilization, and degradation. One the other hand, some evidence has demonstrated that some DNA repair molecular have a crucial role in the initiation of autophagy. In this review, we mainly discuss the interplay between DNA repair and autophagy in anticancer therapy and expect to enlighten some effective strategies for cancer treatment.
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Key Words
- AMPK, adenosine monophosphate-activated protein kinase
- ATG5, autophagy-related gene 5
- ATM, ataxia-telangiectasia mutated
- ATR, ATM and Rad3-related
- BER, base excision repair
- Chk1, check-point kinase 1
- Chk2, check-point kinase 2
- DDR, DNA damage response
- DNA damage
- DNA damage response
- DNA repair
- DNA-PKcs, DNA-dependent protein kinase catalytic subunit
- DSBs, double-strand breaks
- HDAC, histone deacetylases
- HR, homologous recombination
- IR, ionizing radiation
- MGMT, O6 methylguanine –DNA methyltransferase
- MMR, mismatch repair
- MRN, Mre11-Rad50-Nbs1
- NER, nucleotide excision recombination
- NHEJ, non-homologous end joining
- OGG1, 8-oxoguannine DNA glycosidase
- PARP-1, poly (ADP-ribose) polymerase 1
- PI3K, phosphoinositide 3-kinase
- PML, promyelocytic leukemia
- SSBs, single-strand break
- TMZ, temozolomide
- TSC2, tuberous sclerosis complex 2
- anticancer therapy
- apoptosis
- autophagy
- cell cycle arrest
- mTOR, mammalian target of rapamycin
- γ-H2AX, phosphorylated histone
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Affiliation(s)
- Dan Zhang
- a Department of Gastroenterology; Xinqiao Hospital; Third Military Medical University ; Chongqing , China
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Indomethacin suppresses LAMP-2 expression and induces lipophagy and lipoapoptosis in rat enterocytes via the ER stress pathway. J Gastroenterol 2015; 50:541-54. [PMID: 25212253 DOI: 10.1007/s00535-014-0995-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 08/20/2014] [Indexed: 02/04/2023]
Abstract
BACKGROUND Indomethacin enhances small intestinal epithelial cell apoptosis, which may account for mucosal ulceration. However, the involvement of autophagy in indomethacin-induced enterocyte damage is unreported. METHODS Using light microscopy and electron microscopy techniques, Western blot analysis, and pharmacological inhibition of autophagy, we investigated the autophagic response of cultured rat enterocytes to indomethacin treatment (200 µM) at various time points. Furthermore, autophagy was examined in enterocytes of rats given indomethacin by gavage (10 mg/kg). RESULTS Our data indicate that indomethacin induced accumulation of cytoplasmic lipid droplets (LDs) in cultured enterocytes, which was associated with time-dependent autophagic responses. Initially (0-6 h), mediated by endoplasmic reticulum stress and suppression of mammalian target of rapamycin, a predominant cytoprotective lipophagy was activated in indomethacin-treated enterocytes, as evidenced by induction and colocalization of LC3-II with LDs, excessive formation of autophagosomes sequestering LDs (autolipophagosomes; ALPs), and decreased viability of enterocytes on blocking autophagy with 3-methyladenine. On prolonged exposure to indomethacin (6-24 h), there was a decrease of LAMP-2 expression in enterocytes coupled with accumulation of ALPs and LDs with fewer autolysosomes in addition to an elevation of lipoapoptosis. These time-dependent autophagic and apoptotic responses to indomethacin treatment were detected in enterocytes of indomethacin-treated rats, confirming in vitro results. CONCLUSIONS The findings of this study describe a novel mechanism of enterocyte damage by indomethacin mediated by endoplasmic reticulum stress, accumulation of LDs, and subsequent activation of the early phase of cytoprotective lipophagy. This is followed by a late phase characterized by reduced expression of lysosomal autophagic proteins, accumulation of ALPs, and enhanced lipoapoptosis.
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How to reduce the accumulation of autophagic vacuoles in NPC1-deficient neurons: A comparison of two pharmacological strategies. Neuropharmacology 2015; 89:282-9. [DOI: 10.1016/j.neuropharm.2014.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 09/03/2014] [Accepted: 10/06/2014] [Indexed: 12/22/2022]
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Okamoto K, Zaanan A, Kawakami H, Huang S, Sinicrope FA. Reversal of Mutant KRAS-Mediated Apoptosis Resistance by Concurrent Noxa/Bik Induction and Bcl-2/Bcl-xL Antagonism in Colon Cancer Cells. Mol Cancer Res 2014; 13:659-69. [PMID: 25548100 DOI: 10.1158/1541-7786.mcr-14-0476] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 12/10/2014] [Indexed: 12/16/2022]
Abstract
UNLABELLED KRAS mutations are frequently detected in human colorectal cancer and contribute to de novo apoptosis resistance and ultimately therapeutic failure. To overcome KRAS-mediated apoptosis resistance, the irreversible proteasome inhibitor, carfilzomib, was evaluated and found to potently induce Noxa, which was dependent upon c-Myc, and Bik. Isogenic mutant versus wild-type KRAS carcinoma cells showed elevated Bcl-xL, confirmed by KRAS siRNA or ectopic expression. Upregulated Bcl-xL by mutant KRAS was mediated by ERK as indicated by ERK knockdown. Bcl-xL expression was regulated at the level of mRNA and protein as shown using actinomycin D and cyclohexamide, respectively. Suppression of Bcl-xL by shRNA sensitized mutant KRAS cells to carfilzomib. Concurrent Bcl-xL antagonism by the BH3 mimetic ABT-263 combined with carfilzomib synergistically enhanced apoptosis that was dependent on Bax or p53, and was attenuated by Noxa or Bik shRNA. In support of this strategy, ectopically expressed Noxa enhanced apoptosis by ABT-263. Carfilzomib-induced Noxa and Bik sequestered Mcl-1 and ABT-263 released Bik and Bak from Bcl-xL, suggesting a mechanism for drug synergy. These preclinical findings establish mutant KRAS-mediated Bcl-xL upregulation as a key mechanism of apoptosis resistance in KRAS-mutant colorectal cancer. Furthermore, antagonizing Bcl-xL enabled carfilzomib-induced Noxa and Bik to induce synergistic apoptosis that reversed KRAS-mediated resistance. IMPLICATIONS This novel study reveals a promising treatment strategy to overcome apoptosis resistance in KRAS-mutant colorectal cancer by concurrent upregulation of Noxa/Bik and antagonism of Bcl-xL.
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Affiliation(s)
- Koichi Okamoto
- Department of Medicine, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota. Department of Oncology, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota
| | - Aziz Zaanan
- Department of Medicine, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota. Department of Oncology, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota
| | - Hisato Kawakami
- Department of Medicine, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota. Department of Oncology, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota
| | - Shengbing Huang
- Department of Medicine, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota. Department of Oncology, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota
| | - Frank A Sinicrope
- Department of Medicine, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota. Department of Oncology, GI Research Unit, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota.
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ZHANG HONG, LI ZHIHONG, WANG KAIZHONG, REN PING. Combined treatment of XIAP-targeting shRNA and celecoxib synergistically inhibits the tumor growth of non-small cell lung cancer cells in vitro and in vivo. Oncol Rep 2014; 33:1079-88. [DOI: 10.3892/or.2014.3678] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 07/16/2014] [Indexed: 11/05/2022] Open
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Almutairi MS, Hegazy GH, Haiba ME, Ali HI, Khalifa NM, Soliman AEMM. Synthesis, docking and biological activities of novel hybrids celecoxib and anthraquinone analogs as potent cytotoxic agents. Int J Mol Sci 2014; 15:22580-603. [PMID: 25490139 PMCID: PMC4284725 DOI: 10.3390/ijms151222580] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 11/13/2014] [Accepted: 11/20/2014] [Indexed: 11/16/2022] Open
Abstract
Herein, novel hybrid compounds of celecoxib and 2-aminoanthraquinone derivatives have been synthesized using condensation reactions of celecoxib with 2-aminoanthraquinone derivatives or 2-aminoanthraquinon with celecoxib derivatives. Celecoxib was reacted with different acid chlorides, 2-chloroethylisocyanate and bis (2-chloroethyl) amine hydrochloride. These intermediates were then reacted with 2-aminoanthraquinone. Also the same different acid chlorides and 2-chloroethylisocyanate were reacted with 2-aminoanthraquinone and the resulting intermediates were reacted with celecoxib to give isomers for the previous compounds. The antitumor activities against hepatic carcinoma tumor cell line (HEPG2) have been investigated in vitro, and all these compounds showed promising activities, especially compound 3c, 7, and 12. Flexible docking studies involving AutoDock 4.2 was investigated to identify the potential binding affinities and the mode of interaction of the hybrid compounds into two protein tyrosine kinases namely, SRC (Pp60v-src) and platelet-derived growth factor receptor, PDGFR (c-Kit). The compounds in this study have a preferential affinity for the c-Kit PDGFR PTK over the non-receptor tyrosine kinase SRC (Pp60v-src).
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Affiliation(s)
- Maha S Almutairi
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Gehan H Hegazy
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt.
| | - Mogedda E Haiba
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Hamed I Ali
- Department of Pharmaceutical Sciences, Irma Lerma Rangel College of Pharmacy, Texas A&M Health Science Center, Kingsville, TX 78363, USA.
| | - Nagy M Khalifa
- Pharmaceutical Chemistry Department, Drug Exploration & Development Chair (DEDC), College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Abd El-mohsen M Soliman
- Department of Therapeutical Chemistry, Pharmaceutical and Drug Industries Division, National Research Center, Dokki, Cairo 12622, Egypt.
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Koehler BC, Scherr AL, Lorenz S, Elssner C, Kautz N, Welte S, Jaeger D, Urbanik T, Schulze-Bergkamen H. Pan-Bcl-2 inhibitor obatoclax delays cell cycle progression and blocks migration of colorectal cancer cells. PLoS One 2014; 9:e106571. [PMID: 25192188 PMCID: PMC4156353 DOI: 10.1371/journal.pone.0106571] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Accepted: 07/30/2014] [Indexed: 01/24/2023] Open
Abstract
Despite the fact that new treatment regimes have improved overall survival of patients challenged by colorectal cancer (CRC), prognosis in the metastatic situation is still restricted. The Bcl-2 family of proteins has been identified as promising anti cancer drug target. Even though small molecules targeting Bcl-2 proteins are in clinical trials, little is known regarding their effects on CRC. The aim of this study was to preclinically investigate the value of ABT-737 and Obatoclax as anticancer drugs for CRC treatment. The effects of the BH3-mimetics ABT-737 and Obatoclax on CRC cells were assessed using viability and apoptosis assays. Wound healing migration and boyden chamber invasion assays were applied. 3-dimensional cell cultures were used for long term assessment of invasion and proliferation. Clinically relevant concentrations of pan-Bcl-2 inhibitor Obatoclax did not induce cell death. In contrast, the BH3-mimetic ABT-737 induced apoptosis in a dose dependent manner. Obatoclax caused a cell line specific slowdown of CRC cell growth. Furthermore, Obatoclax, but not ABT-737, recovered E-Cadherin expression and led to impaired migration and invasion of CRC cells. The proliferative capacity and invasiveness of CRC cells was strikingly inhibited by low dose Obatoclax in long term 3-dimensional cell cultures. Obatoclax, but not ABT-737, caused a G1-phase arrest accompanied by a downregulation of Cyclin D1 and upregulation of p27 and p21. Overexpression of Mcl-1, Bcl-xL or Bcl-2 reversed the inhibitory effect of Obatoclax on migration but failed to restore the proliferative capacity of Obatoclax-treated CRC cells. The data presented indicate broad and multifaceted antitumor effects of the pan-Bcl-2 inhibitor Obatoclax on CRC cells. In contrast to ABT-737, Obatoclax inhibited migration, invasion and proliferation in sublethal doses. In summary, this study recommends pan-Bcl-2 inhibition as a promising approach for clinical trials in CRC.
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Affiliation(s)
- Bruno Christian Koehler
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
- * E-mail:
| | - Anna-Lena Scherr
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Stephan Lorenz
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Christin Elssner
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Nicole Kautz
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Stefan Welte
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Dirk Jaeger
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Toni Urbanik
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
| | - Henning Schulze-Bergkamen
- National Center for Tumor Diseases, Department of Medical Oncology, Internal Medicine VI, Heidelberg University Hospital, Heidelberg, Germany
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Beclin 1 and UVRAG confer protection from radiation-induced DNA damage and maintain centrosome stability in colorectal cancer cells. PLoS One 2014; 9:e100819. [PMID: 24956373 PMCID: PMC4067383 DOI: 10.1371/journal.pone.0100819] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 05/29/2014] [Indexed: 12/15/2022] Open
Abstract
Beclin 1 interacts with UV-irradiation-resistance-associated gene (UVRAG) to form core complexes that induce autophagy. While cells with defective autophagy are prone to genomic instability that contributes to tumorigenesis, it is unknown whether Beclin1 or UVRAG can regulate the DNA damage/repair response to cancer treatment in established tumor cells. We found that siRNA knockdown of Beclin 1 or UVRAG can increase radiation-induced DNA double strand breaks (DSBs), shown by pATM and γH2Ax, and promote colorectal cancer cell death. Furthermore, knockdown of Beclin 1, UVRAG or ATG5 increased the percentage of irradiated cells with nuclear foci expressing 53BP1, a marker of nonhomologous end joining but not RAD51 (homologous recombination), compared to control siRNA. Beclin 1 siRNA was shown to attenuate UVRAG expression. Cells with a UVRAG deletion mutant defective in Beclin 1 binding showed increased radiation-induced DSBs and cell death compared to cells with ectopic wild-type UVRAG. Knockdown of Beclin 1 or UVRAG, but not ATG5, resulted in a significant increase in centrosome number (γ-tubulin staining) in irradiated cells compared to control siRNA. Taken together, these data indicate that Beclin 1 and UVRAG confer protection against radiation-induced DNA DSBs and may maintain centrosome stability in established tumor cells.
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Cancer therapeutics: Targeting the apoptotic pathway. Crit Rev Oncol Hematol 2014; 90:200-19. [DOI: 10.1016/j.critrevonc.2013.12.012] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 12/05/2013] [Accepted: 12/12/2013] [Indexed: 01/20/2023] Open
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Meloxicam executes its antitumor effects against hepatocellular carcinoma in COX-2- dependent and -independent pathways. PLoS One 2014. [PMID: 24675684 DOI: 10.1371/journal.pone.0092864.ecollection] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Cyclooxygenase (COX)-2 is overexpressed in many types of cancers including hepatocellular carcinoma (HCC). Meloxicam, a selective COX-2 inhibitor, has shown potential therapeutic effects against HCC, but the mechanisms accounting for its anti-cancer activities remain unclear. METHODS AND FINDINGS Meloxicam inhibited the ability of human HCC cells expressing higher levels of COX-2 to migrate, invade, adhere and form colonies through upregulating the expression of E-cadherin and downregulating the expression of matrix metalloproteinase (MMP) -2. Meloxicam induced cell apoptosis by upregulating pro-apoptotic proteins including Bax and Fas-L, and downregulating anti-apoptotic proteins including survivin and myeloid cell leukemia-1 (Mcl-1), through inhibiting phosphorylation of AKT. Addition of prostaglandin E2 (PGE2), the major product of COX-2, could abrogate the effects of meloxicam on the expression of survivin and myeloid cell leukemia-1 (Mcl-1), but not Bax and Fas-L, indicating that meloxicam induces cell apoptosis via both COX-2-dependent and -independent pathways. Meloxicam also induced cell autophagy by upregulating Beclin 1 and light chain 3-II. Specific inhibition of autophagy by 3-methyladenine and chloroquine had little effect on cell apoptosis but could enhance the pro-apoptotic effects of meloxicam by further upregulating the expression of Bax. CONCLUSIONS Meloxicam executes its antitumor effects by targeting the COX-2/MMP-2/E-cadherin, AKT, apoptotic and autophagic pathways in COX-2-dependent and -independent pathways, and inhibition of cell autophagy could help to overcome the resistance to meloxicam-induced apoptosis in HCC.
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Dong X, Li R, Xiu P, Dong X, Xu Z, Zhai B, Liu F, Jiang H, Sun X, Li J, Qiao H. Meloxicam executes its antitumor effects against hepatocellular carcinoma in COX-2- dependent and -independent pathways. PLoS One 2014; 9:e92864. [PMID: 24675684 PMCID: PMC3968044 DOI: 10.1371/journal.pone.0092864] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Accepted: 02/26/2014] [Indexed: 12/12/2022] Open
Abstract
Background Cyclooxygenase (COX)-2 is overexpressed in many types of cancers including hepatocellular carcinoma (HCC). Meloxicam, a selective COX-2 inhibitor, has shown potential therapeutic effects against HCC, but the mechanisms accounting for its anti-cancer activities remain unclear. Methods and Findings Meloxicam inhibited the ability of human HCC cells expressing higher levels of COX-2 to migrate, invade, adhere and form colonies through upregulating the expression of E-cadherin and downregulating the expression of matrix metalloproteinase (MMP) -2. Meloxicam induced cell apoptosis by upregulating pro-apoptotic proteins including Bax and Fas-L, and downregulating anti-apoptotic proteins including survivin and myeloid cell leukemia-1 (Mcl-1), through inhibiting phosphorylation of AKT. Addition of prostaglandin E2 (PGE2), the major product of COX-2, could abrogate the effects of meloxicam on the expression of survivin and myeloid cell leukemia-1 (Mcl-1), but not Bax and Fas-L, indicating that meloxicam induces cell apoptosis via both COX-2-dependent and -independent pathways. Meloxicam also induced cell autophagy by upregulating Beclin 1 and light chain 3-II. Specific inhibition of autophagy by 3-methyladenine and chloroquine had little effect on cell apoptosis but could enhance the pro-apoptotic effects of meloxicam by further upregulating the expression of Bax. Conclusions Meloxicam executes its antitumor effects by targeting the COX-2/MMP-2/E-cadherin, AKT, apoptotic and autophagic pathways in COX-2-dependent and -independent pathways, and inhibition of cell autophagy could help to overcome the resistance to meloxicam-induced apoptosis in HCC.
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Affiliation(s)
- Xiaofeng Dong
- Department of General Surgery, Qianfoshan Hospital, Shandong University, Jinan, China
| | - Rui Li
- Department of General Surgery, Liaocheng People's Hospital, Liaocheng, China
| | - Peng Xiu
- Department of General Surgery, Qianfoshan Hospital, Shandong University, Jinan, China
| | - Xuesong Dong
- The Hepatosplenic Surgery Center, Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Zongzhen Xu
- Department of General Surgery, Qianfoshan Hospital, Shandong University, Jinan, China
| | - Bo Zhai
- The Hepatosplenic Surgery Center, Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Feng Liu
- Department of General Surgery, Qianfoshan Hospital, Shandong University, Jinan, China
| | - Hongchi Jiang
- The Hepatosplenic Surgery Center, Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xueying Sun
- The Hepatosplenic Surgery Center, Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Jie Li
- Department of General Surgery, Qianfoshan Hospital, Shandong University, Jinan, China
- * E-mail: (JL); (HQ)
| | - Haiquan Qiao
- The Hepatosplenic Surgery Center, Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
- * E-mail: (JL); (HQ)
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Heckmann BL, Yang X, Zhang X, Liu J. The autophagic inhibitor 3-methyladenine potently stimulates PKA-dependent lipolysis in adipocytes. Br J Pharmacol 2014; 168:163-71. [PMID: 22817685 DOI: 10.1111/j.1476-5381.2012.02110.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE The class III PI3K inhibitor, 3-methyladenine (3-MA), is commonly used to selectively block autophagy. Recent findings suggest a strong relationship between autophagy and lipid turnover. Here, we explore the effect of 3-MA on adipocyte lipolysis. EXPERIMENTAL APPROACH Assays were performed in 3T3-L1 cells. Cells were treated with 3-MA and wortmannin, a pan PI3K and autophagy inhibitor. Pharmacological and genetic manipulation of endogenous autophagic and lipolytic pathways was used to ascertain the contribution of 3-MA to the observed effects on lipolysis. KEY RESULTS 3T3-L1 cells that were exposed to 3-MA showed a consistent increase in lipolysis, approximately 50% over basal levels. The effect of 3-MA was not secondary to autophagic inhibition as treatment of 3T3-L1 cells with wortmannin yielded no such changes. Dosing and time course experiments showed that 3-MA's ability to activate lipolysis was more sensitive than its inhibitory effect on autophagy. Knockdown of adipose triglyceride lipase (ATGL) negated the stimulatory effect of 3-MA by >90%, indicating that 3-MA enhanced ATGL-dependent hydrolysis of triacylglycerols. Additionally, the lipolytic effect of 3-MA was dependent on the activation of PKA and 3-MA induced a rapid and potent elevation of intracellular cAMP levels in adipocytes. CONCLUSIONS AND IMPLICATIONS Cumulatively, we show that 3-MA potently modulated a cellular mechanism and its underlying signalling pathways not associated with autophagy. Furthermore, we describe a novel stimulatory effect on a major signalling pathway. Our findings provide valuable information to studies employing 3-MA as a specific inhibitor for PI3K and autophagy.
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Affiliation(s)
- Bradlee L Heckmann
- Department of Biochemistry & Molecular Biology, Mayo Clinic, Scottsdale, AZ, USA
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79
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Huang KH, Kuo KL, Ho IL, Chang HC, Chuang YT, Lin WC, Lee PY, Chang SC, Chiang CK, Pu YS, Chou CT, Hsu CH, Liu SH. Celecoxib-induced cytotoxic effect is potentiated by inhibition of autophagy in human urothelial carcinoma cells. PLoS One 2013; 8:e82034. [PMID: 24349176 PMCID: PMC3857231 DOI: 10.1371/journal.pone.0082034] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/20/2013] [Indexed: 11/19/2022] Open
Abstract
Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, can elicit anti-tumor effects in various malignancies. Here, we sought to clarify the role of autophagy in celecoxib-induced cytotoxicity in human urothelial carcinoma (UC) cells. The results shows celecoxib induced cellular stress response such as endoplasmic reticulum (ER) stress, phosopho-SAPK/JNK, and phosopho-c-Jun as well as autophagosome formation in UC cells. Inhibition of autophagy by 3-methyladenine (3-MA), bafilomycin A1 or ATG7 knockdown potentiated celecoxib-induced apoptosis. Up-regulation of autophagy by rapamycin or GFP-LC3B-transfection alleviated celecoxib-induced cytotoxicity in UC cells. Taken together, the inhibition of autophagy enhances therapeutic efficacy of celecoxib in UC cells, suggesting a novel therapeutic strategy against UC.
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Affiliation(s)
- Kuo-How Huang
- Graduate institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Kuan-Lin Kuo
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - I-Lin Ho
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Hong-Chiang Chang
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yuan-Ting Chuang
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Wei-Chou Lin
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Ping-Yi Lee
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Chen Chang
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
- Department of Chemical Engineering, College of Engineering, National Taiwan University, Taipei, Taiwan
| | - Chih-Kang Chiang
- Department of Integrated Diagnostics and Therapeutics, National Taiwan University Hospital, Taipei, Taiwan
| | - Yeong-Shiau Pu
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Chien-Tso Chou
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Chen-Hsun Hsu
- Department of Urology, National Taiwan University Hospital, Taipei, Taiwan
| | - Shing-Hwa Liu
- Graduate institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
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80
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Hou LL, Gao C, Chen L, Hu GQ, Xie SQ. Essential role of autophagy in fucoxanthin-induced cytotoxicity to human epithelial cervical cancer HeLa cells. Acta Pharmacol Sin 2013; 34:1403-10. [PMID: 23974517 DOI: 10.1038/aps.2013.90] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 06/18/2013] [Indexed: 12/13/2022] Open
Abstract
AIM To investigate the effects and the molecular mechanisms of fucoxanthin, a major carotenoid found in edible seaweed, on HeLa cells. METHODS The cytotoxicity of fucoxanthin was evaluated using MTT assay. Cell cycle and apoptosis were evaluated using flow cytometric analysis. Autophagy was detected with acridine orange staining and transient transfection of the GFP-LC3 plasmid into the cells. Protein expression was detected with Western blotting. RESULTS Treatment of HeLa cells with fucoxanthin (10-80 μmol/L) for 48 h caused dose-dependent cytotoxicity with an IC50 value of 55.1±7.6 μmol/L. Fucoxanthin (10, 20, and 40 μmol/L) dose-dependently induced G0/G1 arrest, but did not change the apoptosis of HeLa cells. The same concentrations of fucoxanthin dose-dependently increased the protein expression of LC3 II (the autophagosome marker) and Beclin 1 (the initiation factor for autophagosome formation) in HeLa cells. Moreover, fucoxanthin dose-dependently decreased the levels of phosphorylated Akt and its downstream proteins p53, p70S6K, and mTOR, and increases the expression of PTEN in HeLa cells. Pretreatment of HeLa cells with 3-methyladenine (5 mmol/L) blocked the cytotoxic effect of fucoxanthin as well as fucoxanthin-induced autophagy. CONCLUSION Fucoxanthin exerts autophagy-dependent cytotoxic effect in HeLa cells via inhibition of Akt/mTOR signaling pathway.
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81
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Huang S, Okamoto K, Yu C, Sinicrope FA. p62/sequestosome-1 up-regulation promotes ABT-263-induced caspase-8 aggregation/activation on the autophagosome. J Biol Chem 2013; 288:33654-33666. [PMID: 24121507 DOI: 10.1074/jbc.m113.518134] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Autophagy and apoptosis regulate cancer cell viability in response to cytotoxic stress; however, their functional relationship remains unclear. p62/sequestosome 1 is a multifunctional protein and a signaling hub that shuttles ubiquitinated proteins to the lysosome during autophagy. Autophagy inhibition up-regulates p62, and prior data suggest that p62 may mediate apoptosis. Here, we demonstrate that p62 can regulate a caspase-8-dependent apoptosis in response to the BH3 mimetic agent, ABT-263. Up-regulation of p62 was shown to enhance ABT-263-induced caspase-8 activation that was Bax-dependent and resulted from mitochondrial amplification. Dependence upon caspase-8 was confirmed using caspase-8-deficient cells and by caspase-8 siRNA. Ectopic wild-type p62, but not p62 mutants with loss of ability to promote apoptosis, was shown to co-localize with caspase-8 and to promote its self-aggregation in ABT-263-treated cells, shown using a bimolecular fluorescence complementation assay. Endogenous p62 co-localized with caspase-8 in the presence of ABT-263 plus an autophagy inhibitor. Caspase-8 was shown to interact and co-localize with the autophagosome marker, LC3II. Knockdown of p62 attenuated binding between caspase-8 and LC3II, whereas p62 overexpression enhanced the co-localization of caspase-8 aggregates with LC3. LC3 knockdown did not affect interaction between caspase-8 and p62, suggesting that p62 may facilitate caspase-8 translocation to the autophagosomal membrane. A direct activator of caspase-8, i.e., TRAIL, alone or combined with ABT-263, induced caspase-8 aggregation and co-localization with p62 that was associated with a synergistic drug interaction. Together, these results demonstrate that up-regulation of p62 can mediate apoptosis via caspase-8 in the setting of autophagy inhibition.
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Affiliation(s)
- Shengbing Huang
- Departments of Medicine and Oncology, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota 55905
| | - Koichi Okamoto
- Departments of Medicine and Oncology, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota 55905
| | - Chunrong Yu
- Department of Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Frank A Sinicrope
- Departments of Medicine and Oncology, Mayo Clinic and Mayo Cancer Center, Rochester, Minnesota 55905.
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82
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Dai H, Ding H, Meng XW, Lee SH, Schneider PA, Kaufmann SH. Contribution of Bcl-2 phosphorylation to Bak binding and drug resistance. Cancer Res 2013; 73:6998-7008. [PMID: 24097825 DOI: 10.1158/0008-5472.can-13-0940] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Bcl-2 is phosphorylated on Ser(70) after treatment of cells with spindle poisons. On the basis of effects observed in cells overexpressing Bcl-2 S70E or S70A mutants, various studies have concluded that Ser(70) phosphorylation either enhances or diminishes Bcl-2 function. In the present study, the ability of phosphorylated Bcl-2, as well as the S70E and S70A mutants, to bind and neutralize proapoptotic Bcl-2 family members under cell-free conditions and in intact cells was examined in an attempt to resolve this controversy. Surface plasmon resonance indicated that phosphorylated Bcl-2, Bcl-2 S70E, and Bcl-2 S70A exhibit enhanced binding to Bim and Bak compared with unmodified Bcl-2. This enhanced binding reflected a readily detectable conformation change in the loop domain of Bcl-2. Furthermore, Bcl-2 S70E and S70A bound more Bak and Bim than wild-type Bcl-2 in pull-downs and afforded greater protection against several chemotherapeutic agents. Importantly, binding of endogenous Bcl-2 to Bim also increased during mitosis, when Bcl-2 is endogenously phosphorylated, and disruption of this mitotic Bcl-2/Bim binding with navitoclax or ABT-199, like Bcl-2 downregulation, enhanced the cytotoxicity of paclitaxel. Collectively, these results provide not only a mechanistic basis for the enhanced antiapoptotic activity of phosphorylated Bcl-2, but also an explanation for the ability of BH3 mimetics to enhance taxane sensitivity.
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Affiliation(s)
- Haiming Dai
- Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905
| | - Husheng Ding
- Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905
| | - X Wei Meng
- Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905
| | - Sun-Hee Lee
- Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905
| | - Paula A Schneider
- Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905
| | - Scott H Kaufmann
- Division of Oncology Research, Department of Oncology, Mayo Clinic, Rochester, MN 55905.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905
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83
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Jiang W, Ogretmen B. Autophagy paradox and ceramide. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:783-92. [PMID: 24055889 DOI: 10.1016/j.bbalip.2013.09.005] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 08/22/2013] [Accepted: 09/10/2013] [Indexed: 12/30/2022]
Abstract
Sphingolipid molecules act as bioactive lipid messengers and exert their actions on the regulation of various cellular signaling pathways. Sphingolipids play essential roles in numerous cellular functions, including controlling cell inflammation, proliferation, death, migration, senescence, tumor metastasis and/or autophagy. Dysregulated sphingolipid metabolism has been also implicated in many human cancers. Macroautophagy (referred to here as autophagy) "self-eating" is characterized by nonselective sequestering of cytosolic materials by an isolation membrane, which can be either protective or lethal for cells. Ceramide (Cer), a central molecule of sphingolipid metabolism, has been extensively implicated in the control of autophagy. The increasing evidence suggests that Cer is highly involved in mediating two opposing autophagic pathways, which regulate either cell survival or death, which is referred here as autophagy paradox. However, the underlying mechanism that regulates the autophagy paradox remains unclear. Therefore, this review focuses on recent studies with regard to the regulation of autophagy by Cer and elucidates the roles and mechanisms of action of Cer in controlling autophagy paradox. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology.
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Affiliation(s)
- Wenhui Jiang
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 86 Jonathan Lucas Street, Room 512A, Charleston, SC 29425, USA; Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas Street, Room 512A, Charleston, SC 29425, USA
| | - Besim Ogretmen
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 86 Jonathan Lucas Street, Room 512A, Charleston, SC 29425, USA; Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas Street, Room 512A, Charleston, SC 29425, USA.
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84
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El-Khattouti A, Selimovic D, Haikel Y, Hassan M. Crosstalk between apoptosis and autophagy: molecular mechanisms and therapeutic strategies in cancer. J Cell Death 2013; 6:37-55. [PMID: 25278778 PMCID: PMC4147769 DOI: 10.4137/jcd.s11034] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Both apoptosis and autophagy are highly conserved processes that besides their role in the maintenance of the organismal and cellular homeostasis serve as a main target of tumor therapeutics. Although their important roles in the modulation of tumor therapeutic strategies have been widely reported, the molecular actions of both apoptosis and autophagy are counteracted by cancer protective mechanisms. While apoptosis is a tightly regulated process that is implicated in the removal of damaged or unwanted cells, autophagy is a cellular catabolic pathway that is involved in lysosomal degradation and recycling of proteins and organelles, and thereby is considered an important survival/protective mechanism for cancer cells in response to metabolic stress or chemotherapy. Although the relationship between autophagy and cell death is very complicated and has not been characterized in detail, the molecular mechanisms that control this relationship are considered to be a relevant target for the development of a therapeutic strategy for tumor treatment. In this review, we focus on the molecular mechanisms of apoptosis, autophagy, and those of the crosstalk between apoptosis and autophagy in order to provide insight into the molecular mechanisms that may be essential for the balance between cell survival and death as well as their role as targets for the development of novel therapeutic approaches.
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Affiliation(s)
| | - Denis Selimovic
- Institut National de la Santé et de la Recherche Médicale, U 977, 67000 Strasbourg, France. ; Department of Operative Dentistry and Endodontics, Dental Faculty, University of Strasbourg, 67000 Strasbourg, France
| | - Youssef Haikel
- Institut National de la Santé et de la Recherche Médicale, U 977, 67000 Strasbourg, France. ; Department of Operative Dentistry and Endodontics, Dental Faculty, University of Strasbourg, 67000 Strasbourg, France
| | - Mohamed Hassan
- Institut National de la Santé et de la Recherche Médicale, U 977, 67000 Strasbourg, France. ; Department of Operative Dentistry and Endodontics, Dental Faculty, University of Strasbourg, 67000 Strasbourg, France
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85
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Meloxicam synergistically enhances the in vitro effects of sunitinib malate on bladder-cancer cells. J Appl Biomed 2013. [DOI: 10.2478/v10136-012-0034-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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86
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Gurpinar E, Grizzle WE, Piazza GA. COX-Independent Mechanisms of Cancer Chemoprevention by Anti-Inflammatory Drugs. Front Oncol 2013; 3:181. [PMID: 23875171 PMCID: PMC3708159 DOI: 10.3389/fonc.2013.00181] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 06/26/2013] [Indexed: 12/21/2022] Open
Abstract
Epidemiological and clinical studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs), including cyclooxygenase (COX)-2 selective inhibitors, reduce the risk of developing cancer. Experimental studies in human cancer cell lines and rodent models of carcinogenesis support these observations by providing strong evidence for the antineoplastic properties of NSAIDs. The involvement of COX-2 in tumorigenesis and its overexpression in various cancer tissues suggest that inhibition of COX-2 is responsible for the chemopreventive efficacy of these agents. However, the precise mechanisms by which NSAIDs exert their antiproliferative effects are still a matter of debate. Numerous other studies have shown that NSAIDs can act through COX-independent mechanisms. This review provides a detailed description of the major COX-independent molecular targets of NSAIDs and discusses how these targets may be involved in their anticancer effects. Toxicities resulting from COX inhibition and the suppression of prostaglandin synthesis preclude the long-term use of NSAIDs for cancer chemoprevention. Furthermore, chemopreventive efficacy is incomplete and treatment often leads to the development of resistance. Identification of alternative NSAID targets and elucidation of the biochemical processes by which they inhibit tumor growth could lead to the development of safer and more efficacious drugs for cancer chemoprevention.
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Affiliation(s)
- Evrim Gurpinar
- Department of Pharmacology and Toxicology, The University of Alabama at Birmingham , Birmingham, AL , USA
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87
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Zheng HY, Zhang XY, Wang XF, Sun BC. Autophagy enhances the aggressiveness of human colorectal cancer cells and their ability to adapt to apoptotic stimulus. Cancer Biol Med 2013; 9:105-10. [PMID: 23691463 PMCID: PMC3643655 DOI: 10.3969/j.issn.2095-3941.2012.02.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 06/18/2012] [Indexed: 12/11/2022] Open
Abstract
Objective To investigate LC3B-II and active caspase-3 expression in human colorectal cancer to elucidate the role of autophagy, and to explore the relationship of autophagy with apoptosis in human colorectal cancer. Methods LC3B expression was detected by immunohistochemistry in 53 human colorectal cancer tissues and 20 normal colon tissues. The protein levels of LC3B-II and active caspase-3 were also determined by Western blot analysis in 23 human colorectal cancer tissues and 10 normal colon tissues. Results LC3B was expressed both in cancer cells and normal epithelial cells. LC3B expression in the peripheral area of cancer tissues was correlated with several clinicopathological factors, including tumor differentiation (P=0.002), growth pattern of the tumor margin (P=0.028), pN (P=0.002), pStage (P=0.032), as well as vessel and nerve plexus invasion (P=0.002). The protein level of LC3B-II in cancer tissue was significantly higher than in normal tissue (P=0.038), but the expression of active forms of procaspase-3 in cancer tissue was lower (P=0.041). There was a statistically significant positive correlation between the expression levels of LC3B-II and the active forms of procaspase-3 (r=0.537, P=0.008). Conclusions Autophagy has a prosurvival role in human colorectal cancer. Autophagy enhances the aggressiveness of colorectal cancer cells and their ability to adapt to apoptotic stimulus.
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Affiliation(s)
- Hai-Yang Zheng
- Department of Pathology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
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88
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Yang C, Shogren KL, Goyal R, Bravo D, Yaszemski MJ, Maran A. RNA-dependent protein kinase is essential for 2-methoxyestradiol-induced autophagy in osteosarcoma cells. PLoS One 2013; 8:e59406. [PMID: 23527187 PMCID: PMC3602192 DOI: 10.1371/journal.pone.0059406] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 02/16/2013] [Indexed: 11/26/2022] Open
Abstract
Osteosarcoma is the most common primary malignant bone tumor in children and young adults. Surgical resection and adjunctive chemotherapy are the only widely available options of treatment for this disease. Anti-tumor compound 2-Methoxyestradiol (2-ME) triggers cell death through the induction of apoptosis in osteosarcoma cells, but not in normal osteoblasts. In this report, we have investigated whether autophagy plays a role in 2-ME actions on osteosarcoma cells. Transmission electron microscopy imaging shows that 2-ME treatment leads to the accumulation of autophagosomes in human osteosarcoma cells. 2-ME induces the conversion of the microtubule-associated protein LC3-I to LC3-II, a biochemical marker of autophagy that is correlated with the formation of autophagosomes. Conversion to LC3-II is accompanied by protein degradation in 2-ME-treated cells. 2-ME does not induce autophagosome formation in normal primary human osteoblasts. In addition, 2-ME-dependent autophagosome formation in osteosarcoma cells requires ATG7 expression. Furthermore, 2-ME does not induce accumulation of autophagosomes in osteosarcoma cells that express dominant negative mutant RNA-dependent protein kinase (PKR) and are resistant to anti-proliferative and anti-tumor effects of 2-ME. Taken together, our study shows that 2-ME treatment induces PKR-dependent autophagy in osteosarcoma cells, and that autophagy could play an important role in 2-ME-mediated anti-tumor actions and in the control of osteosarcoma.
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Affiliation(s)
- Caihong Yang
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Orthopedic, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Kristen L. Shogren
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ribu Goyal
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Dalibel Bravo
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Michael J. Yaszemski
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Avudaiappan Maran
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
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89
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Cho YY, Kim DJ, Lee HS, Jeong CH, Cho EJ, Kim MO, Byun S, Lee KY, Yao K, Carper A, Langfald A, Bode AM, Dong Z. Autophagy and cellular senescence mediated by Sox2 suppress malignancy of cancer cells. PLoS One 2013; 8:e57172. [PMID: 23451179 PMCID: PMC3581442 DOI: 10.1371/journal.pone.0057172] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/18/2013] [Indexed: 02/07/2023] Open
Abstract
Autophagy is a critical cellular process required for maintaining cellular homeostasis in health and disease states, but the molecular mechanisms and impact of autophagy on cancer is not fully understood. Here, we found that Sox2, a key transcription factor in the regulation of the "stemness" of embryonic stem cells and induced-pluripotent stem cells, strongly induced autophagic phenomena, including intracellular vacuole formation and lysosomal activation in colon cancer cells. The activation occurred through Sox2-mediated ATG10 gene expression and resulted in the inhibition of cell proliferation and anchorage-independent colony growth ex vivo and tumor growth in vivo. Further, we found that Sox2-induced-autophagy enhanced cellular senescence by up-regulating tumor suppressors or senescence factors, including p16(INK4a), p21 and phosphorylated p53 (Ser15). Notably, knockdown of ATG10 in Sox2-expressing colon cancer cells restored cancer cell properties. Taken together, our results demonstrated that regulation of autophagy mediated by Sox2 is a mechanism-driven novel strategy to treat human colon cancers.
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Affiliation(s)
- Yong-Yeon Cho
- College of Pharmacy, The Catholic University of Korea, Gyeonggi-do, Korea
- * E-mail: (YYC); (ZD)
| | - Dong Joon Kim
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Hye Suk Lee
- College of Pharmacy, The Catholic University of Korea, Gyeonggi-do, Korea
| | - Chul-Ho Jeong
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Eun-Jin Cho
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Myong-Ok Kim
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Sanguine Byun
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Kun-Yeong Lee
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Ke Yao
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Andria Carper
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Alyssa Langfald
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Ann M. Bode
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
| | - Zigang Dong
- The Hormel Institute, University of Minnesota, Austin, Minnesota, United States of America
- * E-mail: (YYC); (ZD)
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Li Y, Zhang J, Ma H, Chen X, Liu T, Jiao Z, He W, Wang F, Liu X, Zeng X. Protective role of autophagy in matrine‑induced gastric cancer cell death. Int J Oncol 2013; 42:1417-26. [PMID: 23404079 DOI: 10.3892/ijo.2013.1817] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 12/07/2012] [Indexed: 11/06/2022] Open
Abstract
Matrine has potent antitumor activity against a broad variety of cancer cells and our previous study showed that both autophagy and apoptosis were activated during matrine-induced gastric cancer cell death. The aim of the present study was to determine the significance of autophagy in antineoplastic effects of matrine and the molecular mechanism by which matrine induces autophagy in gastric cancer cells. Western blot analysis showed that exposure of gastric cancer cells to matrine resulted in the extent of autophagy increasing in a dose- and time-dependent manner by detecting micro-tubule-associated protein 1 light chain 3 (LC3). This induction was due to activation of autophagic flux, as supported using the lysosome inhibitor, bafilomycin A1, which produced an accumulation of LC3-II. Propidium iodide staining demonstrated that matrine induced cell death in a dose-dependent manner and the autophagy inhibitor 3-methyladenine (3-MA) or bafilomycin A1 enhanced lethality of matrine against gastric cancer cells. Moreover, after pretreatment with 3-MA, some of the gastric cancer cells treated with matrine exhibited prototypical characteristics of apoptosis by transmission electron microscopy. The ability of 3-MA to increase matrine-induced apoptosis was further confirmed by Annexin V-FITC/PI staining. Also, the combination of matrine and 3-MA was more potent than matrine alone in inhibiting the proliferation of SGC-7901 cells assessed by sulphorhodamine B assay. Furthermore, administration of the pan-caspase inhibitor zVAD-fmk or autophagy inducer rapamycin decreased the matrine-induced cell death. In addition, matrine treatment did not inhibit the phosphorylation of Akt and its downstream effectors mammalian target of rapamycin (mTOR) as well as p70 ribosomal protein S6 kinase (p70S6K), although the levels of the total Akt and mTOR were decreased. These results suggest that autophagy was activated as a protective mechanism against matrine-induced apoptosis and inhibition of autophagy may be an attractive strategy for enhancing the antitumor potential of matrine in gastric cancer.
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Affiliation(s)
- Yumin Li
- The Second Hospital of Lanzhou University, Lanzhou, Gansu 730030, P.R. China.
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91
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Chen Z, Li Y, Zhang C, Yi H, Wu C, Wang J, Liu Y, Tan J, Wen J. Downregulation of Beclin 1 and impairment of autophagy in a small population of colorectal cancer. Dig Dis Sci 2013; 58:2887-94. [PMID: 23812859 PMCID: PMC3781302 DOI: 10.1007/s10620-013-2732-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 05/29/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Autophagy is a highly conserved mechanism for degradation and recycling of long-lived proteins and damaged organelle to maintain cell homeostasis. Deregulation of autophagy has been associated with tumorigenesis. Beclin 1 is an essential autophagy protein and its upregulation has been observed in most colorectal cancer tissues. However, there is a small population of colorectal cancers with downregulation of Beclin 1. AIM The purpose of this study was to investigate the role autophagy plays in colorectal cancers with downregulation of Beclin 1. METHODS LC3 protein, an autophagosome marker, was assessed by ICH and WB in colorectal cancers tissues. An anti-tumor effect of Beclin 1 was examined by introducing exogenous Beclin 1 in vitro. Colony formation assay, growth curves and mouse xenograft were analysed. RESULTS Our results showed that LC3 was suppressed in the colorectal cancers (9.86 %) with downregulation of Beclin 1. Moreover, overexpression of Beclin 1 inhibited colorectal cancer cell growth and enhanced the rapamycin-induced antitumor effect in vitro. CONCLUSION Downregulation of Beclin 1 and autophagy inhibition play an important role in a part of colorectal cancers. Activating autophagy or overexpression of Beclin 1 may be an effective treatment for some colorectal cancers. Detection of expression profile of Beclin 1 in colorectal cancers could be a strategy for new diagnostic and therapeutic methods.
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Affiliation(s)
- Zhihong Chen
- Department of Pathology, School of Basic Medicine, Central South University, 172 Tong Zi Po Road, Changsha, 410013 China
- Department of Pathology, Hunan Provincial People’s Hospital, Changsha, 410005 China
| | - Yanchun Li
- Department of Pathology, Hunan Provincial People’s Hospital, Changsha, 410005 China
| | - Chi Zhang
- Function Laboratory Centre, University of South China, Hengyang, 421001 China
| | - Hongmei Yi
- Department of Pathology, Hunan Provincial People’s Hospital, Changsha, 410005 China
| | - Chang Wu
- Department of Pathology, School of Basic Medicine, Central South University, 172 Tong Zi Po Road, Changsha, 410013 China
| | - Junpu Wang
- Department of Pathology, School of Basic Medicine, Central South University, 172 Tong Zi Po Road, Changsha, 410013 China
| | - Yuwu Liu
- Department of Pathology, School of Basic Medicine, Central South University, 172 Tong Zi Po Road, Changsha, 410013 China
| | - Jieqiong Tan
- State Key Lab of Medical Genetics, Central South University, Changsha, 410078 China
| | - Jifang Wen
- Department of Pathology, School of Basic Medicine, Central South University, 172 Tong Zi Po Road, Changsha, 410013 China
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92
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Schoultz I, McKay CM, Graepel R, Phan VC, Wang A, Söderholm J, McKay DM. Indomethacin-induced translocation of bacteria across enteric epithelia is reactive oxygen species-dependent and reduced by vitamin C. Am J Physiol Gastrointest Liver Physiol 2012; 303:G536-45. [PMID: 22700821 PMCID: PMC3468559 DOI: 10.1152/ajpgi.00125.2012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The enteric epithelium must absorb nutrients and water and act as a barrier to the entry of luminal material into the body; this barrier function is a key component of innate immunity. Nonsteroidal anti-inflammatory drug (NSAID)-induced enteropathy occurs via inhibition of prostaglandin synthesis and perturbed epithelial mitochondrial activity. Here, the direct effect of NSAIDs [indomethacin, piroxicam (cyclooxygenase 1 and 2 inhibitors), and SC-560 (a cyclooxygenase 1 inhibitor)] on the barrier function of human T84 epithelial cell line monolayers was assessed by transepithelial electrical resistance (TER) and internalization and translocation of a commensal Escherichia coli. Exposure to E. coli in the presence and absence of drugs for 16 h reduced TER; however, monolayers cotreated with E. coli and indomethacin, but not piroxicam or SC-560, displayed significant increases in internalization and translocation of the bacteria. This was accompanied by increased reactive oxygen species (ROS) production, which was also increased in epithelia treated with E. coli only. Colocalization revealed upregulation of superoxide synthesis by mitochondria in epithelia treated with E. coli + indomethacin. Addition of antioxidants (vitamin C or a green tea polyphenol, epigallocathechin gallate) quenched the ROS and prevented the increase in E. coli internalization and translocation evoked by indomethacin, but not the drop in TER. Evidence of increased apoptosis was not observed in this model. The data implicate epithelial-derived ROS in indomethacin-induced barrier dysfunction and show that a portion of the bacteria likely cross the epithelium via a transcellular pathway. We speculate that addition of antioxidants as dietary supplements to NSAID treatment regimens would reduce the magnitude of decreased barrier function, specifically the transepithelial passage of bacteria.
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Affiliation(s)
- Ida Schoultz
- 1Gastrointestinal Research Group, Department of Physiology and Pharmacology, The Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada; and
| | - Catherine M. McKay
- 1Gastrointestinal Research Group, Department of Physiology and Pharmacology, The Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada; and
| | - Rabea Graepel
- 1Gastrointestinal Research Group, Department of Physiology and Pharmacology, The Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada; and
| | - Van C. Phan
- 1Gastrointestinal Research Group, Department of Physiology and Pharmacology, The Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada; and
| | - Arthur Wang
- 1Gastrointestinal Research Group, Department of Physiology and Pharmacology, The Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada; and
| | - Johan Söderholm
- 2Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Derek M. McKay
- 1Gastrointestinal Research Group, Department of Physiology and Pharmacology, The Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada; and
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Saleem A, Dvorzhinski D, Santanam U, Mathew R, Bray K, Stein M, White E, DiPaola RS. Effect of dual inhibition of apoptosis and autophagy in prostate cancer. Prostate 2012; 72:1374-81. [PMID: 22241682 PMCID: PMC3840901 DOI: 10.1002/pros.22487] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 12/13/2011] [Indexed: 12/19/2022]
Abstract
PURPOSE Targeting multiple anti-apoptotic proteins is now possible with the small molecule BH3 domain mimetics such as ABT-737. Given recent studies demonstrating that autophagy is a resistance mechanism to multiple therapeutic agents in the setting of apoptotic inhibition, we hypothesized that hydroxychloroquine (HCQ), an anti-malarial drug that inhibits autophagy, will increase cytotoxicity of ABT-737. EXPERIMENTAL DESIGN Cytotoxicity of ABT-737 and HCQ was assessed in vitro in PC-3 and LNCaP cells, and in vivo in a xenograft mouse model. The role of autophagy as a resistance mechanism was assessed by siRNA knockdown of the essential autophagy gene beclin1. ROS was measured by flow cytometry, and mitophagy assessed by the mCherry-Parkin reporter. RESULTS Induction of autophagy by ABT-737 was a mechanism of resistance in prostate cancer cell lines. Therapeutic inhibition of autophagy with HCQ increased cytotoxicity of ABT-737 both in vitro and in vivo. ABT-737 induced LC-3 and decreased p62 expression by immunoblot in cell lines and by immunohistochemistry in tumors in vivo. Assessment of ROS and mitochondria demonstrated that ROS production by ABT-737 and HCQ was a mechanism of cytotoxicity. CONCLUSIONS We demonstrated that autophagy inhibition with HCQ enhances ABT-737 cytotoxicity in vitro and in vivo, that LC-3 and p62 represent assessable markers in human tissue for future clinical trials, and that ROS induction is a mechanism of cytotoxicity. These results support a new paradigm of dual targeting of apoptosis and autophagy in future clinical studies.
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Affiliation(s)
- Ahamed Saleem
- The Cancer Institute of New Jersey, New Brunswick, New Jersey, USA
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Abstract
Celecoxib is a multifaceted drug with promising anticancer properties. A number of studies have been conducted that implicate the compound in modulating the expression of Bcl-2 family members and mitochondria-mediated apoptosis. The growing data surrounding the role of celecoxib in the regulation of the mitochondrial death pathway provides a platform for ongoing debate. Studies that describe celecoxib's properties as a BH3 mimic or as a direct inhibitor of Bcl-2 are not available. The motivations for this review are: to provide the basis for the development of novel compounds that modulate Bcl-2 expression using celecoxib as a structural starting point and to encourage additional biological studies (such as binding and enzymatic assays) that would provide information regarding celecoxib's role as a Bcl-2 antagonist. The current review summarizes work that identifies the role of celecoxib in blocking the activity of Bcl-2.
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95
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Lin CS, Wang YC, Huang JL, Hung CC, Chen JYF. Autophagy and reactive oxygen species modulate cytotoxicity induced by suppression of ATM kinase activity in head and neck cancer cells. Oral Oncol 2012; 48:1152-8. [PMID: 22763242 DOI: 10.1016/j.oraloncology.2012.05.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 05/22/2012] [Accepted: 05/25/2012] [Indexed: 12/22/2022]
Abstract
OBJECTIVES Because Ataxia Telangiectasia Mutated (ATM)-deficient cells are hypersensitive to ionizing irradiation and DNA-damaging agents, ATM kinase inhibition is thought to enhance radiochemotherapy efficacy. In this study, we investigated the roles of autophagy and reactive oxygen species (ROS) in modulating cytotoxicity induced by suppression of ATM kinase in head and neck cancer cells. MATERIALS AND METHODS We use KU55933 to inhibit ATM kinase activity. The cell viability was determined by MTT assays. Autophagy was examined by Western blot for LC3-II and microscopy for acidic vesicles and EGFP-LC3 punctate formation. DCF-DA staining and flow cytometry were used for analyzing ROS generation. RESULTS we found that KU55933 reduced cell viability in several head and neck cancer cell lines. KU55933-treated cells showed increased cytoplasmic vesicles, LC3-II accumulation, and EGFP-LC3 punctate formation, indicating that autophagy was induced. KU55933 also increased ROS generation, which was required for autophagy induction because the ROS scavenger N-acetyl-L-cysteine could reduce LC3-II accumulation. KU55933-induced autophagy played a cytoprotective role against ROS-mediated cytotoxicity because autophagy inhibition by chloroquine augmented KU55933's cytotoxicity. In addition, KU55933 reduced cisplatin-resistant head and neck cancer cell viabilities, and induced LC3-II accumulation in these cells. CONCLUSION Together, these results shed light on KU55933's therapeutic values as well as autophagy inhibitors in treating primary and cisplatin-resistant head and neck cancers.
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Affiliation(s)
- Chang-Shen Lin
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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96
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DIN FARHATVN, VALANCIUTE ASTA, HOUDE VANESSAP, ZIBROVA DARIA, GREEN KEVINA, SAKAMOTO KEI, ALESSI DARIOR, DUNLOP MALCOLMG. Aspirin inhibits mTOR signaling, activates AMP-activated protein kinase, and induces autophagy in colorectal cancer cells. Gastroenterology 2012; 142:1504-15.e3. [PMID: 22406476 PMCID: PMC3682211 DOI: 10.1053/j.gastro.2012.02.050] [Citation(s) in RCA: 312] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Revised: 02/21/2012] [Accepted: 02/27/2012] [Indexed: 12/27/2022]
Abstract
BACKGROUND & AIMS Aspirin reduces the incidence of and mortality from colorectal cancer (CRC) by unknown mechanisms. Cancer cells have defects in signaling via the mechanistic target of rapamycin (mTOR), which regulates proliferation. We investigated whether aspirin affects adenosine monophosphate-activated protein kinase (AMPK) and mTOR signaling in CRC cells. METHODS The effects of aspirin on mTOR signaling, the ribosomal protein S6, S6 kinase 1 (S6K1), and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1) were examined in CRC cells by immunoblotting. Phosphorylation of AMPK was measured; the effects of loss of AMPKα on the aspirin-induced effects of mTOR were determined using small interfering RNA (siRNA) in CRC cells and in AMPK(α1/α2-/-) mouse embryonic fibroblasts. LC3 and ULK1 were used as markers of autophagy. We analyzed rectal mucosa samples from patients given 600 mg aspirin, once daily for 1 week. RESULTS Aspirin reduced mTOR signaling in CRC cells by inhibiting the mTOR effectors S6K1 and 4E-BP1. Aspirin changed nucleotide ratios and activated AMPK in CRC cells. mTOR was still inhibited by aspirin in CRC cells after siRNA knockdown of AMPKα, indicating AMPK-dependent and AMPK-independent mechanisms of aspirin-induced inhibition of mTOR. Aspirin induced autophagy, a feature of mTOR inhibition. Aspirin and metformin (an activator of AMPK) increased inhibition of mTOR and Akt, as well as autophagy in CRC cells. Rectal mucosal samples from patients given aspirin had reduced phosphorylation of S6K1 and S6. CONCLUSIONS Aspirin is an inhibitor of mTOR and an activator of AMPK, targeting regulators of intracellular energy homeostasis and metabolism. These could contribute to its protective effects against development of CRC.
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Affiliation(s)
- FARHAT V. N. DIN
- Colon Cancer Genetics Group and Academic Coloproctology, Institute of Genetics and Molecular Medicine, University of Edinburgh and Medical Research Council Human Genetics Unit, Western General Hospital Edinburgh, United Kingdom
| | - ASTA VALANCIUTE
- Colon Cancer Genetics Group and Academic Coloproctology, Institute of Genetics and Molecular Medicine, University of Edinburgh and Medical Research Council Human Genetics Unit, Western General Hospital Edinburgh, United Kingdom
| | - VANESSA P. HOUDE
- The Medical Research Council Protein Phosphorylation Unit, University of Dundee, Dundee, United Kingdom
| | - DARIA ZIBROVA
- The Medical Research Council Protein Phosphorylation Unit, University of Dundee, Dundee, United Kingdom
| | - KEVIN A. GREEN
- Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - KEI SAKAMOTO
- The Medical Research Council Protein Phosphorylation Unit, University of Dundee, Dundee, United Kingdom
| | - DARIO R. ALESSI
- The Medical Research Council Protein Phosphorylation Unit, University of Dundee, Dundee, United Kingdom
| | - MALCOLM G. DUNLOP
- Colon Cancer Genetics Group and Academic Coloproctology, Institute of Genetics and Molecular Medicine, University of Edinburgh and Medical Research Council Human Genetics Unit, Western General Hospital Edinburgh, United Kingdom
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Huang KH, Kuo KL, Chen SC, Weng TI, Chuang YT, Tsai YC, Pu YS, Chiang CK, Liu SH. Down-regulation of glucose-regulated protein (GRP) 78 potentiates cytotoxic effect of celecoxib in human urothelial carcinoma cells. PLoS One 2012; 7:e33615. [PMID: 22438966 PMCID: PMC3306428 DOI: 10.1371/journal.pone.0033615] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 02/13/2012] [Indexed: 11/30/2022] Open
Abstract
Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor that has been reported to elicit anti-proliferative response in various tumors. In this study, we aim to investigate the antitumor effect of celecoxib on urothelial carcinoma (UC) cells and the role endoplasmic reticulum (ER) stress plays in celecoxib-induced cytotoxicity. The cytotoxic effects were measured by MTT assay and flow cytometry. The cell cycle progression and ER stress-associated molecules were examined by Western blot and flow cytometry. Moreover, the cytotoxic effects of celecoxib combined with glucose-regulated protein (GRP) 78 knockdown (siRNA), (−)-epigallocatechin gallate (EGCG) or MG132 were assessed. We demonstrated that celecoxib markedly reduces the cell viability and causes apoptosis in human UC cells through cell cycle G1 arrest. Celecoxib possessed the ability to activate ER stress-related chaperones (IRE-1α and GRP78), caspase-4, and CCAAT/enhancer binding protein homologous protein (CHOP), which were involved in UC cell apoptosis. Down-regulation of GRP78 by siRNA, co-treatment with EGCG (a GRP78 inhibitor) or with MG132 (a proteasome inhibitor) could enhance celecoxib-induced apoptosis. We concluded that celecoxib induces cell cycle G1 arrest, ER stress, and eventually apoptosis in human UC cells. The down-regulation of ER chaperone GRP78 by siRNA, EGCG, or proteosome inhibitor potentiated the cytotoxicity of celecoxib in UC cells. These findings provide a new treatment strategy against UC.
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Affiliation(s)
- Kuo-How Huang
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
- Department of Urology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
- * E-mail: (KHH); (SHL)
| | - Kuan-Lin Kuo
- Department of Urology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Shyh-Chyan Chen
- Department of Urology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Te-I Weng
- Department of Forensic Medicine, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Yuan-Ting Chuang
- Department of Urology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Yu-Chieh Tsai
- Department of Oncology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Yeong-Shiau Pu
- Department of Urology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Chih-Kang Chiang
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
- Department of Integrated Diagnostics and Therapeutics, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
| | - Shing-Hwa Liu
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
- Department of Urology, College of Medicine, National Taiwan University, and National Taiwan University Hospital, Taipei, Taiwan
- * E-mail: (KHH); (SHL)
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98
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Novel Insights into the Interplay between Apoptosis and Autophagy. Int J Cell Biol 2012; 2012:317645. [PMID: 22496691 PMCID: PMC3312193 DOI: 10.1155/2012/317645] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 12/31/2011] [Indexed: 12/19/2022] Open
Abstract
For several decades, apoptosis has taken center stage as the principal mechanism of programmed cell death (type I cell death) in mammalian tissues. Autophagic cell death (type II) is characterized by the massive accumulation of autophagic vacuoles in the cytoplasm of cells. The autophagic process is activated as an adaptive response to a variety of extracellular and intracellular stresses, including nutrient deprivation, hormonal or therapeutic treatment, pathogenic infection, aggregated and misfolded proteins, and damaged organelles. Increasing evidence indicates that autophagy is associated with a number of pathological processes, including cancer. The regulation of autophagy in cancer cells is complex since it can enhance cancer cell survival in response to certain stresses, while it can also act to suppress the initiation of cancer growth. This paper focused on recent advances regarding autophagy in cancer and the techniques currently available to manipulate autophagy.
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99
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The crosstalk between autophagy and apoptosis: where does this lead? Protein Cell 2012; 3:17-27. [PMID: 22314807 DOI: 10.1007/s13238-011-1127-x] [Citation(s) in RCA: 260] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Accepted: 12/06/2011] [Indexed: 12/19/2022] Open
Abstract
Recent advances in the understanding of the molecular processes contributing to autophagy have provided insight into the relationship between autophagy and apoptosis. In contrast to the concept of "autophagic cell death," accumulating evidence suggests that autophagy serves a largely cytoprotective role in physiologically relevant conditions. The cytoprotective function of autophagy is mediated in many circumstances by negative modulation of apoptosis. Apoptotic signaling, in turn, serves to inhibit autophagy. While the mechanisms mediating the complex counter-regulation of apoptosis and autophagy are not yet fully understood, important points of crosstalk include the interactions between Beclin-1 and Bcl-2/Bcl-xL and between FADD and Atg5, caspase- and calpain-mediated cleavage of autophagy-related proteins, and autophagic degradation of caspases. Continued investigation of these and other means of crosstalk between apoptosis and autophagy is necessary to elucidate the mechanisms controlling the balance between survival and death both under normal conditions and in diseases including cancer.
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Abstract
Ceramides are a class of sphingolipids that are abundant in cell membranes. They are important structural components of the membrane but can also act as second messengers in various signaling pathways. Until recently, ceramides and dihydroceramides were considered as a single functional class of lipids and no distinction was made between molecules with different chain lengths. However, based on the development of high-throughput, structure-specific and quantitative analytical methods to measure ceramides, it has now become clear that in cellular systems the amounts of ceramides differ with respect to their chain length. Further studies have indicated that some functions of ceramides are chain-length dependent. In this review, we discuss the chain length-specific differences of ceramides including their pathological impact on Alzheimer's disease, inflammation, autophagy, apoptosis and cancer.
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Affiliation(s)
- Sabine Grösch
- pharmazentrum frankfurt/ZAFES, Institut für Klinische Pharmakologie, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany.
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