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Abstract
Autophagy represents a catabolic program involved in the degradation of cellular components via lysosomes. It serves to mitigate cellular stress and to provide metabolic precursors especially upon starvation. Thereby, autophagy can support the survival of cancer cells. In addition, there is now convincing evidence showing that under certain conditions autophagy can also foster cell death. This dual function of autophagy is also relevant upon anticancer treatment, as many chemotherapeutic agents engage autophagy. A better understanding of the molecular mechanisms that are critical for mediating autophagic cell death in cancer cells will be instrumental to selectively interfere with this cellular program in order to increase the cancer cell’s response to cytotoxic drugs. This review illustrates how anticancer drug-induced autophagy is involved in mediating cell death.
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Affiliation(s)
- Simone Fulda
- Institute for Experimental Cancer Research in Pediatrics, Goethe-University Frankfurt, Frankfurt, Germany.,German Cancer Consortium (DKTK), Partner Site Frankfurt, Frankfurt, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
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202
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Leng ZG, Lin SJ, Wu ZR, Guo YH, Cai L, Shang HB, Tang H, Xue YJ, Lou MQ, Zhao W, Le WD, Zhao WG, Zhang X, Wu ZB. Activation of DRD5 (dopamine receptor D5) inhibits tumor growth by autophagic cell death. Autophagy 2017; 13:1404-1419. [PMID: 28613975 DOI: 10.1080/15548627.2017.1328347] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Dopamine agonists such as bromocriptine and cabergoline have been successfully used in the treatment of pituitary prolactinomas and other neuroendocrine tumors. However, their therapeutic mechanisms are not fully understood. In this study we demonstrated that DRD5 (dopamine receptor D5) agonists were potent inhibitors of pituitary tumor growth. We further found that DRD5 activation increased production of reactive oxygen species (ROS), inhibited the MTOR pathway, induced macroautophagy/autophagy, and led to autophagic cell death (ACD) in vitro and in vivo. In addition, DRD5 protein was highly expressed in the majority of human pituitary adenomas, and treatment of different human pituitary tumor cell cultures with the DRD5 agonist SKF83959 resulted in growth suppression, and the efficacy was correlated with the expression levels of DRD5 in the tumors. Furthermore, we found that DRD5 was expressed in other human cancer cells such as glioblastomas, colon cancer, and gastric cancer. DRD5 activation in these cell lines suppressed their growth, inhibited MTOR activity, and induced autophagy. Finally, in vivo SKF83959 also inhibited human gastric cancer cell growth in nude mice. Our studies revealed novel mechanisms for the tumor suppressive effects of DRD5 agonists, and suggested a potential use of DRD5 agonists as a novel therapeutic approach in the treatment of different human tumors and cancers.
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Affiliation(s)
- Zhi Gen Leng
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Shao Jian Lin
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Ze Rui Wu
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Yu Hang Guo
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Lin Cai
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Han Bing Shang
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Hao Tang
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Ya Jun Xue
- c Department of Neurosurgery, Shanghai General Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Mei Qing Lou
- c Department of Neurosurgery, Shanghai General Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Wenxiu Zhao
- e Neuroendocrine Research Laboratory , Massachusetts General Hospital and Harvard Medical School , Boston , MA , USA
| | - Wei-Dong Le
- d Center for Clinical Research on Neurological Diseases , First Affiliated Hospital of Dalian Medical University , Dalian , China
| | - Wei Guo Zhao
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xun Zhang
- e Neuroendocrine Research Laboratory , Massachusetts General Hospital and Harvard Medical School , Boston , MA , USA
| | - Zhe Bao Wu
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China.,b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
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203
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Methods for monitoring Ca 2+ and ion channels in the lysosome. Cell Calcium 2017; 64:20-28. [DOI: 10.1016/j.ceca.2016.12.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Revised: 12/07/2016] [Accepted: 12/07/2016] [Indexed: 12/22/2022]
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204
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Yu J, Lan L, Lewin SJ, Rogers SA, Roy A, Wu X, Gao P, Karanicolas J, Aubé J, Sun B, Xu L. Identification of novel small molecule Beclin 1 mimetics activating autophagy. Oncotarget 2017; 8:51355-51369. [PMID: 28881653 PMCID: PMC5584254 DOI: 10.18632/oncotarget.17977] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 05/06/2017] [Indexed: 01/07/2023] Open
Abstract
Anti-apoptotic proteins Bcl-2 and Bcl-xL could block autophagy by binding to Beclin 1 protein, an essential inducer of autophagy. Compounds mimicking Beclin 1 might be able to disrupt Bcl-xL/2-Beclin 1 interaction, free out Beclin 1, and thus trigger autophagy. In order to identify small molecule Beclin 1 mimetics, a fluorescence polarization-based high-throughput screening of 50,316 compounds was carried out with a Z' score of 0.82 ± 0.05, and an outcome of 58 hits. After the structure analysis, three acridine analogues were unveiled and confirmed using the fluorescence polarization assay and the surface plasmon resonance assay. Moreover, a set of 17 additional acridine analogues was prepared and tested. Compound 7 showed selectivity for Bcl-xL (KD = 6.5 μM) over Bcl-2 (KD = 160 μM) protein, and potent cytotoxicity (nanomolar scale) in PC-3, PC-3a and DU145 prostate cancer cells. Furthermore, induction of autophagy was also demonstrated in PC-3 and PC-3a cells treated with some acridine compounds by LC3 conversion immunoblotting and LC3 fluorescence microscopy. These Beclin 1 mimetics will be invaluable tools for developing novel autophagy inducers, better understanding the roles of autophagy in cancer, and will contribute to cancer therapy.
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Affiliation(s)
- Jia Yu
- 1 School of Chemistry and Chemical Engineering, Southeast University, Nanjing 210089, China,2 Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Lan Lan
- 2 Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Seth J. Lewin
- 2 Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Steven A. Rogers
- 3 Center of Biomedical Research Excellence, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Anuradha Roy
- 4 High Throughput Screening Laboratory, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Xiaoqing Wu
- 2 Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Philip Gao
- 5 COBRE-PSF Protein Production Group, The University of Kansas, Lawrence, Kansas 66045, USA
| | - John Karanicolas
- 2 Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66045, USA,6 Center for Bioinformatics, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Jeffrey Aubé
- 3 Center of Biomedical Research Excellence, The University of Kansas, Lawrence, Kansas 66045, USA,7 Department of Medicinal Chemistry, The University of Kansas, Lawrence, Kansas 66045, USA
| | - Baiwang Sun
- 1 School of Chemistry and Chemical Engineering, Southeast University, Nanjing 210089, China
| | - Liang Xu
- 2 Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66045, USA
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205
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Yu Q, Liu L, Wang P, Yao Y, Xue Y, Liu Y. EMAP-II sensitize U87MG and glioma stem-like cells to temozolomide via induction of autophagy-mediated cell death and G2/M arrest. Cell Cycle 2017; 16:1085-1092. [PMID: 28436750 DOI: 10.1080/15384101.2017.1315492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Despite the fact that temozolomide (TMZ) has been widely accepted as the key chemotherapeutic agent to prolong the survival of patients with glioblastoma, failure and recurrence cases can still be observed in clinics. Glioma stem-like cells (GSCs) are thought to be responsible for the drug resistance. In this study, we investigate whether endothelial monocyte-activating polypeptide-II (EMAP-II), a pro-inflammatory cytokine, can enhance TMZ cytotoxicity on U87MG and GSCs or not. As described in prior research, GSCs have been isolated from U87MG and maintained in the serum-free DMEM/F12 medium containing EGF, b-FGF, and B27. TMZ and/or EMAP-II administration were performed for 72 h, respectively. The results showed that TMZ combined with EMAP-II inhibit the proliferation of U87MG and GSCs by a larger measure than TMZ single treatment by decreasing the IC50. EMAP-II also enhanced TMZ-induced autophagy-mediated cell death and G2/M arrest. Moreover, we found that EMAP-II functioned a targeted suppression on mTOR, which may involve in the anti-neoplasm mechanism. The results suggest that EMAP-II could be considered as a combined chemotherapeutic agent against glioblastoma by sensitizing U87MG and GSCs to TMZ.
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Affiliation(s)
- Qi Yu
- a Department of Neurosurgery , Shengjing Hospital of China Medical University , Shenyang , China.,b Liaoning Research Center for Translational Medicine in Nervous System Disease , Shenyang China
| | - Libo Liu
- c Department of Neurobiology , College of Basic Medicine, China Medical University , Shenyang China.,d Key Laboratory of Cell Biology , Ministry of Public Health of China, Key Laboratory of Medical Cell Biology, Ministry of Education of China, China Medical University , Shenyang China
| | - Ping Wang
- c Department of Neurobiology , College of Basic Medicine, China Medical University , Shenyang China.,d Key Laboratory of Cell Biology , Ministry of Public Health of China, Key Laboratory of Medical Cell Biology, Ministry of Education of China, China Medical University , Shenyang China
| | - Yilong Yao
- a Department of Neurosurgery , Shengjing Hospital of China Medical University , Shenyang , China.,b Liaoning Research Center for Translational Medicine in Nervous System Disease , Shenyang China
| | - Yixue Xue
- c Department of Neurobiology , College of Basic Medicine, China Medical University , Shenyang China.,d Key Laboratory of Cell Biology , Ministry of Public Health of China, Key Laboratory of Medical Cell Biology, Ministry of Education of China, China Medical University , Shenyang China
| | - Yunhui Liu
- a Department of Neurosurgery , Shengjing Hospital of China Medical University , Shenyang , China.,b Liaoning Research Center for Translational Medicine in Nervous System Disease , Shenyang China
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206
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Huang YH, Sun Y, Huang FY, Li YN, Wang CC, Mei WL, Dai HF, Tan GH, Huang C. Toxicarioside O induces protective autophagy in a sirtuin-1-dependent manner in colorectal cancer cells. Oncotarget 2017; 8:52783-52791. [PMID: 28881770 PMCID: PMC5581069 DOI: 10.18632/oncotarget.17189] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 03/21/2017] [Indexed: 02/05/2023] Open
Abstract
Colorectal cancer is the most common cancer. It has high morbidity and mortality worldwide, and more effective treatment strategies need to be developed. Toxicarioside O (TCO), a natural product derived from Antiaris toxicaria, has been shown to be a potential anticancer agent. However, the molecular mechanisms involved remain poorly understood. In this study, our results demonstrated that TCO can induce both apoptosis and autophagy in colorectal cancer cells. Moreover, TCO-induced autophagy was due to the increase of the expression and activity of the enzyme sirtuin-1 (SIRT1), and subsequent inhibition of the Akt/mTOR pathway. Inhibition of SIRT1 activity by its inhibitor, EX-527, attenuated TCO-induced autophagy. Of interest, inhibition of autophagy by chloroguine, an autophagy inhibitor, enhanced TCO-induced apoptotic cell death, suggesting that autophagy plays a protective role in TCO-induced apoptosis. Together, these findings suggest that combination of TCO and autophagy inhibitor may be a novel strategy suitable for potentiating the anticancer activity of TCO for treatment of colorectal cancer.
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Affiliation(s)
- Yong-Hao Huang
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China
| | - Yan Sun
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China
| | - Feng-Ying Huang
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China
| | - Yue-Nan Li
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China
| | - Cai-Chun Wang
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China
| | - Wen-Li Mei
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571199, China
| | - Hao-Fu Dai
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571199, China
| | - Guang-Hong Tan
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China
| | - Canhua Huang
- Key Laboratory of Tropical Diseases and Translational Medicine of the Ministry of Education & Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571199, China.,State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, China
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207
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Su Z, Li G, Liu C, Ren S, Deng T, Zhang S, Tian Y, Liu Y, Qiu Y. Autophagy inhibition impairs the epithelial-mesenchymal transition and enhances cisplatin sensitivity in nasopharyngeal carcinoma. Oncol Lett 2017; 13:4147-4154. [PMID: 28599416 PMCID: PMC5453060 DOI: 10.3892/ol.2017.5963] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 02/17/2017] [Indexed: 12/17/2022] Open
Abstract
Drug resistance restricts the efficacy of cisplatin in the treatment of nasopharyngeal carcinoma (NPC). Increasing evidence indicates that autophagy and the epithelial-mesenchymal transition (EMT) participate in cancer progression and drug sensitivity. The aim of the present study was to investigate the function of autophagy and EMT in cisplatin treatment, and to reveal the underlying impact of autophagy on the EMT process in NPC. Transmission electron microscopy assays and western blot analyses confirmed that cisplatin activates autophagy in NPC cells. Alterations in cell morphology and biomolecular markers confirmed that cisplatin induces the EMT phenotype in NPC cells. Cell viability assays showed that the combination of the autophagy inhibitor chloroquine (CQ) increased the cytotoxicity of cisplatin in NPC cells and that the EMT inducer transforming growth factor β1 promoted the resistance to cisplatin in NPC cells. Moreover, autophagy inhibition by CQ and microtubule-associated protein 1 light chain 3B-knockdown reversed the EMT phenotype in NPC cells. In conclusion, autophagy and the EMT process promote cisplatin resistance in NPC cells, while the inhibition of autophagy impairs the EMT process.
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Affiliation(s)
- Zhongwu Su
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Guo Li
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Chao Liu
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Shuling Ren
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Tengbo Deng
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Shuiting Zhang
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Yongquan Tian
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Yong Liu
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
| | - Yuanzheng Qiu
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.,Otolaryngology Major Disease Research Key Laboratory of Hunan, Changsha, Hunan 410008, P.R. China
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208
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Xie YZ, Ma WL, Meng JM, Ren XQ. Knockdown of ZFPL1 results in increased autophagy and autophagy‑related cell death in NCI‑N87 and BGC‑823 human gastric carcinoma cell lines. Mol Med Rep 2017; 15:2633-2642. [PMID: 28447717 DOI: 10.3892/mmr.2017.6300] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 09/28/2016] [Indexed: 11/06/2022] Open
Abstract
Macroautophagy, which will hereafter be referred to as autophagy, is an evolutionarily conserved process, during which cells recycle and remove damaged organelles and proteins in response to cellular stress. However, the mechanisms underlying the regulation of autophagy remain to be fully elucidated. The present study demonstrated that knockdown of zinc finger protein like 1 (ZFPL1) induces autophagy and increases autophagic cell death in NCI‑N87 and BGC‑823 human gastric carcinoma cell lines. To examine the role of ZFPL1 in gastric carcinoma cells, ZFPL1 expression was downregulated by lentiviral infection. Zinc finger domain‑FLAG was used to compete with ZFPL1 for golgin A2/GM130 binding. Autophagy was analyzed by red fluorescent protein‑microtubule‑associated protein 1A/1B‑light chain 3 (LC3) puncta, LC3I to LC3II conversion, and p62 expression. The results demonstrated that knockdown of ZFPL1 was able to significantly increase cell death rate. However, ZFPL1 knockdown exerted almost no effect on the expression of apoptosis‑associated markers, including B cell lymphoma 2 (Bcl‑2), Bcl‑x, Bcl‑2‑associated X protein, BH3 interacting domain death agonist, p53, and the classical caspase family members, caspase‑3, caspase‑8 and caspase‑9. An endogenous ZFPL1‑GM130 association was identified in NCI‑N87 cells and BGC‑823 cells by co‑immunoprecipitation. Furthermore, cell death was restricted following treatment of ZFPL1 knockdown cells with an autophagy inhibitor. Therefore, knockdown of ZFPL1 expression may induce cell death via autophagy, rather than apoptosis. These results suggest that ZFPL1 may serve an important role in regulating autophagy in NCI‑N87 and BGC‑823 cells.
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Affiliation(s)
- Yong-Zheng Xie
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
| | - Wan-Li Ma
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
| | - Ji-Ming Meng
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
| | - Xue-Qun Ren
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
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209
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Yao Z, Xie F, Li M, Liang Z, Xu W, Yang J, Liu C, Li H, Zhou H, Qu LH. Oridonin induces autophagy via inhibition of glucose metabolism in p53-mutated colorectal cancer cells. Cell Death Dis 2017; 8:e2633. [PMID: 28230866 PMCID: PMC5386482 DOI: 10.1038/cddis.2017.35] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 12/21/2016] [Accepted: 01/10/2017] [Indexed: 12/26/2022]
Abstract
The Warburg effect is an important characteristic of tumor cells, making it an attractive therapeutic target. Current anticancer drug development strategies predominantly focus on inhibitors of the specific molecular effectors involved in tumor cell proliferation. These drugs or natural compounds, many of which target the Warburg effect and the underlying mechanisms, still need to be characterized. To elucidate the anticancer effects of a natural diterpenoid, oridonin, we first demonstrated the anticancer activity of oridonin both in vitro and in vivo in colorectal cancer (CRC) cells. Then miRNA profiling of SW480 cells revealed those intracellular signaling related to energy supply was affected by oridonin, suggesting that glucose metabolism is a potential target for CRC therapy. Moreover, our results indicated that oridonin induced metabolic imbalances by significantly inhibiting glucose uptake and reducing lactate export through significantly downregulating the protein levels of GLUT1 and MCT1 in vitro and vivo. However, the ATP level in oridonin-treated CRC cells was not decreased when oridonin blocked the glucose supply, indicating that oridonin induced autophagy process, an important ATP source in cancer cells. The observation was then supported by the results of LC3-II detection and transmission electron microscopy analysis, which confirmed the presence of autophagy. Furthermore, p-AMPK was rapidly deactivated following oridonin treatment, resulting in downregulation of GLUT1 and induction of autophagy in the cancer cells. Thus our finding helped to clarify the anticancer mechanisms of oridonin and suggested it could be applied as a glucose metabolism-targeting agent for cancer treatment.
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Affiliation(s)
- Zhuo Yao
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Fuhua Xie
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Min Li
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zirui Liang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Wenli Xu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jianhua Yang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Chang Liu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Hongwangwang Li
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Hui Zhou
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Liang-Hu Qu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
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210
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Chen K, Lv X, Li W, Yu F, Lin J, Ma J, Xiao D. Autophagy Is a Protective Response to the Oxidative Damage to Endplate Chondrocytes in Intervertebral Disc: Implications for the Treatment of Degenerative Lumbar Disc. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:4041768. [PMID: 28321270 PMCID: PMC5340961 DOI: 10.1155/2017/4041768] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 12/22/2016] [Indexed: 02/07/2023]
Abstract
Low back pain (LBP) is the leading cause of disability in the elderly. Intervertebral disc degeneration (IDD) was considered as the main cause for LBP. Degeneration of cartilaginous endplate was a crucial harmful factor during the initiation and development of IDD. Oxidative stress was implicated in IDD. However, the underlying molecular mechanism for the degeneration of cartilaginous endplate remains elusive. Herein, we found that oxidative stress could induce apoptosis and autophagy in endplate chondrocytes evidenced by western blot analysis, flow cytometry, immunofluorescence staining, GFP-LC3B transfection, and MDC staining. In addition, we also found that the apoptosis of endplate chondrocytes was significantly increased after the inhibition of autophagy by bafilomycin A1 shown by flow cytometry. Furthermore, mTOR pathway upstream autophagy was greatly suppressed suggested by western blot assay. In conclusion, our study strongly revealed that oxidative stress could increase autophagy and apoptosis of endplate chondrocytes in intervertebral disc. The increase of autophagy activity could prevent endplate chondrocytes from apoptosis. The autophagy in endplate chondrocytes induced by oxidative stress was mTOR dependent. These findings might shed some new lights on the mechanism for IDD and provide new strategies for the treatments of IDD.
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Affiliation(s)
- Ke Chen
- Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong 518036, China
| | - Xiaohua Lv
- Department of Pharmacology, Guangdong Medical University, Zhanjiang, Guangdong 524023, China
| | - Wei Li
- Department of Orthopaedics, Peking University Shenzhen Hospital, Guangdong 518036, China
| | - Fei Yu
- Department of Orthopaedics, Peking University Shenzhen Hospital, Guangdong 518036, China
| | - Jianjing Lin
- Department of Orthopaedics, Peking University Shenzhen Hospital, Guangdong 518036, China
| | - Junxuan Ma
- Department of Orthopaedics, Peking University Shenzhen Hospital, Guangdong 518036, China
| | - Deming Xiao
- Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong 518036, China
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211
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NOS1 S-nitrosylates PTEN and inhibits autophagy in nasopharyngeal carcinoma cells. Cell Death Discov 2017; 3:17011. [PMID: 28243469 PMCID: PMC5317009 DOI: 10.1038/cddiscovery.2017.11] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/28/2016] [Accepted: 04/15/2016] [Indexed: 02/06/2023] Open
Abstract
Autophagy is a cellular survival mechanism that involves the catabolic degradation of damaged proteins and organelles during periods of metabolic stress, and when overly stimulated, commonly contributes to cell death. Nitric oxide (NO), a potent cellular messenger, participates in a complex mechanism which assists in controlling autophagy. However, the mechanism by which endogenous NO formed by distinct isoforms of nitric oxide synthase (NOS) helps to regulate autophagy in cancer cells remains unclear. Here we report that NOS1 reduces excessive levels of autophagy and promotes the survival of nasopharyngeal carcinoma cells. We found that inhibition of NOS1 increased cell death resulting from siRNA or the use of pharmacologic agents; and this effect was reversed by the autophagy inhibitor, chloroquine. The role of NOS1 in the autophagy process depended on the activation of AKT/mTOR signaling by S-nitrosylation of phosphatase and tensin homolog (PTEN) proteins. The mechanism by which NOS1 modifies PTEN protein might involve a direct interaction between these two molecules. Moreover, in an in vivo study, the NOS1 inhibitor N(G)-nitro-L-arginine methyl ester activated AKT/mTOR signaling and promoted autophagy in xenograph tumors. Our studies demonstrated that NOS1 prevents excessive autophagy via S-nitrosylation of PTEN, and activation of the AKT/mTOR signaling pathway. PTEN and the AKT/mTOR signaling pathway are promising targets for improving the chemotherapeutic treatment of cancer.
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212
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Xia D, Zhang YT, Xu GP, Yan WW, Pan XR, Tong JH. Sertraline exerts its antitumor functions through both apoptosis and autophagy pathways in acute myeloid leukemia cells. Leuk Lymphoma 2017; 58:1-10. [PMID: 28278721 DOI: 10.1080/10428194.2017.1287358] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It has been found that sertraline, a widely used antidepressant drug, possessed antitumor roles in a variety of cancers including liver cancer, colorectal cancer and lymphoma. In this study, we provided evidences that sertraline had potent antiproliferative activity not only in acute myeloid leukemia (AML) cell lines but also in the fresh leukemia cells from AML patients, and could induce cell death through both apoptosis and autophagy pathways. Moreover, we found that inhibiting autophagy pathway could partially attenuate sertraline-induced apoptosis and cell growth inhibition, indicating that sertraline-induced autophagy process could facilitate AML cell apoptosis to some degree. However, blocking apoptosis pathway seemed no obvious effects on sertraline-caused autophagy as well as cell growth inhibition. Our results suggested a potential application value of sertraline in the treatment of AML patients, furnishing some perspectives for novel therapeutic strategies in leukemia.
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Affiliation(s)
- Di Xia
- a State Key Laboratory of Medical Genomics and Faculty of Medical Laboratory Science , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , PR China
| | - Ying-Ting Zhang
- a State Key Laboratory of Medical Genomics and Faculty of Medical Laboratory Science , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , PR China
| | - Gui-Ping Xu
- a State Key Laboratory of Medical Genomics and Faculty of Medical Laboratory Science , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , PR China
| | - Wei-Wei Yan
- a State Key Laboratory of Medical Genomics and Faculty of Medical Laboratory Science , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , PR China
| | - Xiao-Rong Pan
- a State Key Laboratory of Medical Genomics and Faculty of Medical Laboratory Science , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , PR China
| | - Jian-Hua Tong
- a State Key Laboratory of Medical Genomics and Faculty of Medical Laboratory Science , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , PR China
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213
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Gilardini Montani MS, Granato M, Santoni C, Del Porto P, Merendino N, D'Orazi G, Faggioni A, Cirone M. Histone deacetylase inhibitors VPA and TSA induce apoptosis and autophagy in pancreatic cancer cells. Cell Oncol (Dordr) 2017; 40:167-180. [PMID: 28160167 DOI: 10.1007/s13402-017-0314-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2017] [Indexed: 02/06/2023] Open
Abstract
PURPOSE Histone deacetylase inhibitors (HDACi) are anti-neoplastic agents that are known to affect the growth of different cancer types, but their underlying mechanisms are still incompletely understood. Here, we compared the effects of two HDACi, i.e., Trichostatin A (TSA) and Valproic Acid (VPA), on the induction of cell death and autophagy in pancreatic cancer-derived cells that exhibit a high metastatic capacity and carry KRAS/p53 double mutations. METHODS Cell viability and proliferation tests were carried out using Trypan blue dye exclusion, MTT and BrdU assays. FACS analyses were carried out to assess cell cycle progression, apoptosis, reactive oxygen species (ROS) production and mitochondrial depolarization, while Western blot and immunoprecipitation analyses were employed to detect proteins involved in apoptosis and autophagy. RESULTS We found that both VPA and TSA can induce apoptosis in Panc1 and PaCa44 pancreatic cancer-derived cells by triggering mitochondrial membrane depolarization, Cytochrome c release and Caspase 3 activation, although VPA was more effective than TSA, especially in Panc1 cells. As underlying molecular events, we found that ERK1/2 was de-phosphorylated and that the c-Myc and mutant p53 protein levels were reduced after VPA and, to a lesser extent, after TSA treatment. Up-regulation of p21 and Puma was also observed, concomitantly with mutant p53 degradation. In addition, we found that in both cell lines VPA increased the pro-apoptotic Bim level, reduced the anti-apoptotic Mcl-1 level and increased ROS production and autophagy, while TSA was able to induce these effects only in PaCA44 cells. CONCLUSIONS From our results we conclude that both VPA and TSA can induce pancreatic cancer cell apoptosis and autophagy. VPA appears have a stronger and broader cytotoxic effect than TSA and, thus, may represent a better choice for anti-pancreatic cancer therapy.
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Affiliation(s)
| | - Marisa Granato
- Department of Experimental Medicine, La Sapienza University of Rome, V.le Regina Elena 324, 00161, Rome, Italy
| | - Claudio Santoni
- Department of Ecological and Biological Sciences (DEB), Tuscia University, Viterbo, Italy
| | - Paola Del Porto
- Department of Biology and Biotechnology 'Charles Darwin', La Sapienza University of Rome, Rome, Italy
| | - Nicolò Merendino
- Department of Ecological and Biological Sciences (DEB), Tuscia University, Viterbo, Italy
| | - Gabriella D'Orazi
- Department of Research, Advanced Diagnostic and Technological Innovation, Regina Elena National Cancer Institute, Rome, Italy.,Department of Medical Sciences, Tumor Biology Unit, University "G. D'Annunzio", Chieti, Italy
| | - Alberto Faggioni
- Department of Experimental Medicine, La Sapienza University of Rome, V.le Regina Elena 324, 00161, Rome, Italy.
| | - Mara Cirone
- Department of Experimental Medicine, La Sapienza University of Rome, V.le Regina Elena 324, 00161, Rome, Italy.
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214
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Ravegnini G, Sammarini G, Nannini M, Pantaleo MA, Biasco G, Hrelia P, Angelini S. Gastrointestinal stromal tumors (GIST): Facing cell death between autophagy and apoptosis. Autophagy 2017; 13:452-463. [PMID: 28055310 DOI: 10.1080/15548627.2016.1256522] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Autophagy and apoptosis are 2 fundamental biological mechanisms that may cooperate or be antagonistic, although both are involved in deciding the fate of cells in physiological or pathological conditions. These 2 mechanisms coexist simultaneously in cells and share common upstream signals and stimuli. Autophagy and apoptosis play pivotal roles in cancer development. Autophagy plays a key function in maintaining tumor cell survival by providing energy during unfavorable metabolic conditions through its recycling mechanism, and supporting the high energy requirement for metabolism and growth. This review focuses on gastrointestinal stromal tumors and cell death through autophagy and apoptosis, taking into account the involvement of both of these processes in tumor development and growth and as mechanisms of drug resistance. We also focus on the crosstalk between autophagy and apoptosis as an emerging field with major implications for the development of novel therapeutic options.
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Affiliation(s)
- Gloria Ravegnini
- a Department of Pharmacy and Biotechnology , University of Bologna , Bologna Italy
| | - Giulia Sammarini
- a Department of Pharmacy and Biotechnology , University of Bologna , Bologna Italy
| | - Margherita Nannini
- b Department of Specialized , Experimental and Diagnostic Medicine, Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy
| | - Maria A Pantaleo
- b Department of Specialized , Experimental and Diagnostic Medicine, Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy.,c "Giorgio Prodi" Cancer Research Center, University of Bologna , Bologna , Italy
| | - Guido Biasco
- b Department of Specialized , Experimental and Diagnostic Medicine, Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy.,c "Giorgio Prodi" Cancer Research Center, University of Bologna , Bologna , Italy
| | - Patrizia Hrelia
- a Department of Pharmacy and Biotechnology , University of Bologna , Bologna Italy
| | - Sabrina Angelini
- a Department of Pharmacy and Biotechnology , University of Bologna , Bologna Italy
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215
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Bose C, Shah SV, Karaduta OK, Kaushal GP. Carbamylated Low-Density Lipoprotein (cLDL)-Mediated Induction of Autophagy and Its Role in Endothelial Cell Injury. PLoS One 2016; 11:e0165576. [PMID: 27973558 PMCID: PMC5156412 DOI: 10.1371/journal.pone.0165576] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 10/13/2016] [Indexed: 01/08/2023] Open
Abstract
Patients with chronic kidney disease (CKD) have high risk of cardiovascular complications. Plasma levels of carbamylated proteins produced by urea-derived isocyanate or thiocyanate are elevated in CKD patients and that they are significant predictors of cardiovascular events and all-cause mortality. Carbamylated LDL (cLDL) has pro-atherogenic properties and is known to affect major biological processes relevant to atherosclerosis including endothelial cell injury. The underlying mechanisms of cLDL-induced endothelial cell injury are not well understood. Although autophagy has been implicated in atherosclerosis, cLDL-mediated induction of autophagy and its role in endothelial cell injury is unknown. Our studies demonstrate that human coronary artery endothelial cells (HCAECs) respond to cLDL by specific induction of key autophagy proteins including LC3-I, beclin-1, Atg5, formation of lipid-conjugated LC3-II protein, and formation of punctate dots of autophagosome-associated LC3-II. We demonstrated that autophagy induction is an immediate response to cLDL and occurred in a dose and time-dependent manner. Inhibition of cLDL-induced autophagy by a specific siRNA to LC3 as well as by an autophagy inhibitor provided protection from cLDL-induced cell death and DNA fragmentation. Our studies demonstrate that autophagy plays an important role in cLDL-mediated endothelial cell injury and may provide one of the underlying mechanisms for the pathogenesis of cLDL-induced atherosclerosis in CKD patients.
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Affiliation(s)
- Chhanda Bose
- Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
- University of Arkansas for Medical Sciences, Department of Internal Medicine, Little Rock, Arkansas, United States of America
| | - Sudhir V. Shah
- Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
- University of Arkansas for Medical Sciences, Department of Internal Medicine, Little Rock, Arkansas, United States of America
| | - Oleg K. Karaduta
- University of Arkansas for Medical Sciences, Department of Biochemistry, Little Rock, Arkansas, United States of America
| | - Gur P. Kaushal
- Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
- University of Arkansas for Medical Sciences, Department of Internal Medicine, Little Rock, Arkansas, United States of America
- University of Arkansas for Medical Sciences, Department of Biochemistry, Little Rock, Arkansas, United States of America
- * E-mail:
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216
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Ramos-Torres Á, Bort A, Morell C, Rodríguez-Henche N, Díaz-Laviada I. The pepper's natural ingredient capsaicin induces autophagy blockage in prostate cancer cells. Oncotarget 2016; 7:1569-83. [PMID: 26625315 PMCID: PMC4811481 DOI: 10.18632/oncotarget.6415] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 11/16/2015] [Indexed: 12/22/2022] Open
Abstract
Capsaicin, the pungent ingredient of red hot chili peepers, has been shown to have anti-cancer activities in several cancer cells, including prostate cancer. Several molecular mechanisms have been proposed on its chemopreventive action, including ceramide accumulation, endoplasmic reticulum stress induction and NFκB inhibition. However, the precise mechanisms by which capsaicin exerts its anti-proliferative effect in prostate cancer cells remain questionable. Herein, we have tested the involvement of autophagy on the capsaicin mechanism of action on prostate cancer LNCaP and PC-3 cells. The results showed that capsaicin induced prostate cancer cell death in a time- and concentration-dependent manner, increased the levels of microtubule-associated protein light chain 3-II (LC3-II, a marker of autophagy) and the accumulation of the cargo protein p62 suggesting an autophagy blockage. Moreover, confocal microscopy revealed that capsaicin treatment increased lysosomes which co-localized with LC3 positive vesicles in a similar extent to that produced by the lysosomal protease inhibitors E64 and pepstatin pointing to an autophagolysosomes breakdown inhibition. Furthermore, we found that capsaicin triggered ROS generation in cells, while the levels of ROS decreased with N-acetyl-cysteine (NAC), a ROS scavenger. Co-treatment of cells with NAC and capsaicin abrogated the effects of capsaicin on autophagy and cell death. Normal prostate PNT2 and RWPE-1 cells were more resistant to capsaicin-induced cytotoxicity and did not accumulate p62 protein. Taken together, these results suggest that ROS-mediated capsaicin-induced autophagy blockage contributes to antiproliferation in prostate cancer cells, which provides new insights into the anticancer molecular mechanism of capsaicin.
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Affiliation(s)
- Ágata Ramos-Torres
- Department of System Biology, Biochemistry and Molecular Biology Unit, School of Medicine, Alcala University, Alcala de Henares 28871, Madrid, Spain
| | - Alicia Bort
- Department of System Biology, Biochemistry and Molecular Biology Unit, School of Medicine, Alcala University, Alcala de Henares 28871, Madrid, Spain
| | - Cecilia Morell
- Department of System Biology, Biochemistry and Molecular Biology Unit, School of Medicine, Alcala University, Alcala de Henares 28871, Madrid, Spain
| | - Nieves Rodríguez-Henche
- Department of System Biology, Biochemistry and Molecular Biology Unit, School of Medicine, Alcala University, Alcala de Henares 28871, Madrid, Spain
| | - Inés Díaz-Laviada
- Department of System Biology, Biochemistry and Molecular Biology Unit, School of Medicine, Alcala University, Alcala de Henares 28871, Madrid, Spain
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217
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Gómez-Sintes R, Ledesma MD, Boya P. Lysosomal cell death mechanisms in aging. Ageing Res Rev 2016; 32:150-168. [PMID: 26947122 DOI: 10.1016/j.arr.2016.02.009] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 02/22/2016] [Accepted: 02/29/2016] [Indexed: 12/14/2022]
Abstract
Lysosomes are degradative organelles essential for cell homeostasis that regulate a variety of processes, from calcium signaling and nutrient responses to autophagic degradation of intracellular components. Lysosomal cell death is mediated by the lethal effects of cathepsins, which are released into the cytoplasm following lysosomal damage. This process of lysosomal membrane permeabilization and cathepsin release is observed in several physiopathological conditions and plays a role in tissue remodeling, the immune response to intracellular pathogens and neurodegenerative diseases. Many evidences indicate that aging strongly influences lysosomal activity by altering the physical and chemical properties of these organelles, rendering them more sensitive to stress. In this review we focus on how aging alters lysosomal function and increases cell sensitivity to lysosomal membrane permeabilization and lysosomal cell death, both in physiological conditions and age-related pathologies.
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Affiliation(s)
- Raquel Gómez-Sintes
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biologicas, CIB-CSIC, C/Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María Dolores Ledesma
- Department of Molecular Neurobiology, Centro Biologia Molecular Severo Ochoa, CSIC-UAM, C/Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Patricia Boya
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biologicas, CIB-CSIC, C/Ramiro de Maeztu 9, 28040 Madrid, Spain.
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218
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Hambright HG, Ghosh R. Autophagy: In the cROSshairs of cancer. Biochem Pharmacol 2016; 126:13-22. [PMID: 27789215 DOI: 10.1016/j.bcp.2016.10.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 10/21/2016] [Indexed: 12/18/2022]
Abstract
Two prominent features of tumors that contribute to oncogenic survival signaling are redox disruption, or oxidative stress phenotype, and high autophagy signaling, making both phenomena ideal therapeutic targets. However, the relationship between redox disruption and autophagy signaling is not well characterized and the clinical impact of reactive oxygen species (ROS)-generating chemotherapeutics on autophagy merits immediate attention as autophagy largely contributes to chemotherapeutic resistance. In this commentary we focus on melanoma, using it as an example to provide clarity to current literature regarding the roles of autophagy and redox signaling which can be applicable to initiation and maintenance of most tumor types. Further, we address the crosstalk between ROS and autophagy signaling during pharmacological intervention and cell fate decisions. We attempt to elucidate the role of autophagy in regulating cell fate following treatment with ROS-generating agents in preclinical and clinical settings and discuss the emerging role of autophagy in cell fate decisions and as a cell death mechanism. We also address technical aspects of redox and autophagy evaluation in experimental design and data interpretation. Lastly, we present a provocative view of the clinical relevance, emerging challenges in dual targeting of redox and autophagy pathways for therapy, and the future directions to be addressed in order to advance both basic and translational aspects of this field.
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Affiliation(s)
- Heather Graham Hambright
- Department of Urology, University of Texas Health Science Center at San Antonio, South Texas Research Facility Campus, 8403 Floyd Curl Drive, San Antonio, TX 78229, USA; Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, South Texas Research Facility Campus, 8403 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Rita Ghosh
- Department of Urology, University of Texas Health Science Center at San Antonio, South Texas Research Facility Campus, 8403 Floyd Curl Drive, San Antonio, TX 78229, USA; Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, South Texas Research Facility Campus, 8403 Floyd Curl Drive, San Antonio, TX 78229, USA; Department of Pharmacology, University of Texas Health Science Center at San Antonio, South Texas Research Facility Campus, 8403 Floyd Curl Drive, San Antonio, TX 78229, USA; Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, South Texas Research Facility Campus, 8403 Floyd Curl Drive, San Antonio, TX 78229, USA.
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219
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Antonietti P, Linder B, Hehlgans S, Mildenberger IC, Burger MC, Fulda S, Steinbach JP, Gessler F, Rödel F, Mittelbronn M, Kögel D. Interference with the HSF1/HSP70/BAG3 Pathway Primes Glioma Cells to Matrix Detachment and BH3 Mimetic-Induced Apoptosis. Mol Cancer Ther 2016; 16:156-168. [PMID: 27777286 DOI: 10.1158/1535-7163.mct-16-0262] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 09/14/2016] [Accepted: 09/28/2016] [Indexed: 11/16/2022]
Abstract
Malignant gliomas exhibit a high intrinsic resistance against stimuli triggering apoptotic cell death. HSF1 acts as transcription factor upstream of HSP70 and the HSP70 co-chaperone BAG3 that is overexpressed in glioblastoma. To specifically target this resistance mechanism, we applied the selective HSF1 inhibitor KRIBB11 and the HSP70/BAG3 interaction inhibitor YM-1 in combination with the pan-Bcl-2 inhibitor AT-101. Here, we demonstrate that lentiviral BAG3 silencing significantly enhances AT-101-induced cell death and reactivates effector caspase-mediated apoptosis in U251 glioma cells with high BAG3 expression, whereas these sensitizing effects were less pronounced in U343 cells expressing lower BAG3 levels. KRIBB11 decreased protein levels of HSP70, BAG3, and the antiapoptotic Bcl-2 protein Mcl-1, and both KRIBB11 and YM-1 elicited significantly increased mitochondrial dysfunction, effector caspase activity, and apoptotic cell death after combined treatment with AT-101 and ABT-737. Depletion of BAG3 also led to a pronounced loss of cell-matrix adhesion, FAK phosphorylation, and in vivo tumor growth in an orthotopic mouse glioma model. Furthermore, it reduced the plating efficiency of U251 cells in three-dimensional clonogenic assays and limited clonogenic survival after short-term treatment with AT-101. Collectively, our data suggest that the HSF1/HSP70/BAG3 pathway plays a pivotal role for overexpression of prosurvival Bcl-2 proteins and cell death resistance of glioma. They also support the hypothesis that interference with BAG3 function is an effective novel approach to prime glioma cells to anoikis. Mol Cancer Ther; 16(1); 156-68. ©2016 AACR.
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Affiliation(s)
- Patrick Antonietti
- Experimental Neurosurgery, Goethe University Hospital, Frankfurt am Main, Germany
| | - Benedikt Linder
- Experimental Neurosurgery, Goethe University Hospital, Frankfurt am Main, Germany
| | - Stephanie Hehlgans
- Radiotherapy and Oncology, Goethe University Hospital, Frankfurt am Main, Germany
| | | | | | - Simone Fulda
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Hospital, Frankfurt am Main, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Joachim P Steinbach
- Dr. Senckenberg Institute of Neurooncology.,German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Florian Gessler
- Department of Neurosurgery, Goethe University Hospital, Frankfurt am Main, Germany
| | - Franz Rödel
- Radiotherapy and Oncology, Goethe University Hospital, Frankfurt am Main, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Michel Mittelbronn
- German Cancer Consortium (DKTK), Heidelberg, Germany.,Edinger Institute, Goethe University Hospital, Frankfurt am Main, Germany
| | - Donat Kögel
- Experimental Neurosurgery, Goethe University Hospital, Frankfurt am Main, Germany. .,German Cancer Consortium (DKTK), Heidelberg, Germany
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220
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Mandell MA, Jain A, Kumar S, Castleman MJ, Anwar T, Eskelinen EL, Johansen T, Prekeris R, Deretic V. TRIM17 contributes to autophagy of midbodies while actively sparing other targets from degradation. J Cell Sci 2016; 129:3562-3573. [PMID: 27562068 DOI: 10.1242/jcs.190017] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 08/13/2016] [Indexed: 12/16/2022] Open
Abstract
TRIM proteins contribute to selective autophagy, a process whereby cells target specific cargo for autophagic degradation. In a previously reported screen, TRIM17 acted as a prominent inhibitor of bulk autophagy, unlike the majority of TRIMs, which had positive roles. Nevertheless, TRIM17 showed biochemical hallmarks of autophagy-inducing TRIMs. To explain this paradox, here, we investigated how TRIM17 inhibits selective autophagic degradation of a subset of targets while promoting degradation of others. We traced the inhibitory function of TRIM17 to its actions on the anti-autophagy protein Mcl-1, which associates with and inactivates Beclin 1. TRIM17 expression stabilized Mcl-1-Beclin-1 complexes. Despite its ability to inhibit certain types of selective autophagy, TRIM17 promoted the removal of midbodies, remnants of the cell division machinery that are known autophagy targets. The selective loss of anti-autophagy Mcl-1 from TRIM17-Beclin-1 complexes at midbodies correlated with the ability of TRIM17 to promote midbody removal. This study further expands the roles of TRIMs in regulating selective autophagy by showing that a single TRIM can, depending upon a target, either positively or negatively regulate autophagy.
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Affiliation(s)
- Michael A Mandell
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, Albuquerque, NE NM 87131 USA
| | - Ashish Jain
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsø - The Arctic University of Norway, Tromsø 9037, Norway Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo N-0379, Norway Center for Cancer Biomedicine, Faculty of Medicine, University of Oslow, Montebello, Oslo N-0379, Norway
| | - Suresh Kumar
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, Albuquerque, NE NM 87131 USA
| | - Moriah J Castleman
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, Albuquerque, NE NM 87131 USA
| | - Tahira Anwar
- Department of Biosciences, University of Helsinki, Helsinki 00014, Finland
| | | | - Terje Johansen
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, Oslo N-0379, Norway
| | - Rytis Prekeris
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, 12801 East 17th Avenue, Aurora, CO 80045, USA
| | - Vojo Deretic
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, 915 Camino de Salud, Albuquerque, NE NM 87131 USA
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221
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Boya P, Esteban-Martínez L, Serrano-Puebla A, Gómez-Sintes R, Villarejo-Zori B. Autophagy in the eye: Development, degeneration, and aging. Prog Retin Eye Res 2016; 55:206-245. [PMID: 27566190 DOI: 10.1016/j.preteyeres.2016.08.001] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 08/15/2016] [Accepted: 08/18/2016] [Indexed: 02/06/2023]
Abstract
Autophagy is a catabolic pathway that promotes the degradation and recycling of cellular components. Proteins, lipids, and even whole organelles are engulfed in autophagosomes and delivered to the lysosome for elimination. In response to stress, autophagy mediates the degradation of cell components, which are recycled to generate the nutrients and building blocks required to sustain cellular homeostasis. Moreover, it plays an important role in cellular quality control, particularly in neurons, in which the total burden of altered proteins and damaged organelles cannot be reduced by redistribution to daughter cells through cell division. Research has only begun to examine the role of autophagy in the visual system. The retina, a light-sensitive tissue, detects and transmits electrical impulses through the optic nerve to the visual cortex in the brain. Both the retina and the eye are exposed to a variety of environmental insults and stressors, including genetic mutations and age-associated alterations that impair their function. Here, we review the main studies that have sought to explain autophagy's importance in visual function. We describe the role of autophagy in retinal development and cell differentiation, and discuss the implications of autophagy dysregulation both in physiological aging and in important diseases such as age-associated macular degeneration and glaucoma. We also address the putative role of autophagy in promoting photoreceptor survival and discuss how selective autophagy could provide alternative means of protecting retinal cells. The findings reviewed here underscore the important role of autophagy in maintaining proper retinal function and highlight novel therapeutic approaches for blindness and other diseases of the eye.
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Affiliation(s)
- Patricia Boya
- Autophagy Lab, Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain.
| | - Lorena Esteban-Martínez
- Autophagy Lab, Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Ana Serrano-Puebla
- Autophagy Lab, Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Raquel Gómez-Sintes
- Autophagy Lab, Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Beatriz Villarejo-Zori
- Autophagy Lab, Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040, Madrid, Spain
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222
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Yang M, Pi H, Li M, Xu S, Zhang L, Xie J, Tian L, Tu M, He M, Lu Y, Yu Z, Zhou Z. From the Cover: Autophagy Induction Contributes to Cadmium Toxicity in Mesenchymal Stem Cells via AMPK/FOXO3a/BECN1 Signaling. Toxicol Sci 2016; 154:101-114. [PMID: 27492225 DOI: 10.1093/toxsci/kfw144] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Mesenchymal stem cells (MSCs) are a valuable in vitro model for investigating the bone toxicity of cadmium (Cd). Autophagy has been proposed to play a pivotal role in Cd-mediated toxicity. The FOXO family proteins are important transcription factors that are essential to autophagy induction. This study investigated the role of autophagy in Cd-induced skeleton damage and its potential mechanism. We exposed MSCs to different concentrations of cadmium chloride (3.5, 7, and 14 μM) for 24 h. We demonstrated that Cd treatment increased autophagic flux, and inhibition of autophagic process using BENC1 gene silencing blocked Cd-induced cell death. Cd treatment also significantly increased mRNA levels of various essential autophagy-related genes including ATG5, ATG12, BECN1, LC3, and ULK1. Specifically, Cd increased FOXO3a and FOXO1 expression at the mRNA and protein levels, and AMPK was demonstrated to enhance FOXO3a nuclear translocation and transcriptional activity by phosphorylating FOXO3a at specific serine residues (Ser588) in Cd-treated MSCs. Notably, knockdown of FOXO3a, but not FOXO1, prevented autophagy-related genes expression and autophagosome formation after Cd treatment. Taken together, our results demonstrate that Cd-induced cell death via the overactivation of FOXO3a-dependent autophagy. Modulation of the FOXO3a autophagy pathway may offer novel therapeutic approaches for the treatment of Cd-induced bone damage.
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Affiliation(s)
- Min Yang
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Huifeng Pi
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Min Li
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Shangcheng Xu
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Lei Zhang
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Jia Xie
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Li Tian
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Manyu Tu
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Mindi He
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Yonghui Lu
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Zhengping Yu
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
| | - Zhou Zhou
- Department of Occupational Health, Third Military Medical University, Chongqing 400038, People's Republic of China
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Falasca L, Torino F, Marconi M, Costantini M, Pompeo V, Sentinelli S, De Salvo L, Patrizio M, Padula C, Gallucci M, Piacentini M, Malorni W. AMBRA1 and SQSTM1 expression pattern in prostate cancer. Apoptosis 2016; 20:1577-86. [PMID: 26423274 PMCID: PMC4602066 DOI: 10.1007/s10495-015-1176-3] [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] [Indexed: 12/19/2022]
Abstract
Prostate cancer is among the most commonly diagnosed male diseases and a leading cause of cancer mortality in men. There is emerging evidence that autophagy plays an important role in malignant cell survival and offers protection from the anti-cancer drugs in prostate cancer cells. AMBRA1 and the autophagic protein sequestosome-1 (SQSTM1; p62) expression were evaluated by immunohistochemistry and western blot on tissue samples from both benign and malignant prostatic lesions. The data reported in this pilot study demonstrated an increased expression of AMBRA1 and SQSTM1, which were also associated with an accumulation of LC3II in prostate cancer but not in benign lesion. In the present study we found that: (i) at variance with benign lesion, prostate cancer cells underwent SQSTM1 accumulation, i.e., clearly displayed a defective autophagic process but, also, (ii) prostate cancer accumulated AMBRA1 and (iii) this increase positively correlated with the Gleason score. These results underscore a possible implication of autophagy in prostate cancer phenotype and of AMBRA1 as possible cancer progression biomarker in this malignancy.
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Affiliation(s)
- Laura Falasca
- Laboratory of Cell Biology and Electron Microscopy, National Institute for Infectious Diseases I.R.C.C.S. 'L. Spallanzani', Rome, Italy
| | - Francesco Torino
- Department of Systems Medicine, Chair of Medical Oncology, Tor Vergata University of Rome, Rome, Italy
| | - Matteo Marconi
- Department of Drug Research and Medicine Evaluation, Istituto Superiore di Sanita', Rome, Italy
| | - Manuela Costantini
- Department of Urology, Regina Elena National Cancer Institute, IRCCS, Rome, Italy.,Laboratory of Molecular Medicine and Biotechnology, University Campus Bio-Medico of Rome, Rome, Italy
| | - Vincenzo Pompeo
- Department of Urology, Regina Elena National Cancer Institute, IRCCS, Rome, Italy
| | - Steno Sentinelli
- Department of Pathology, Regina Elena National Cancer, Institute, IRCCS, Rome, Italy
| | - Laura De Salvo
- Department of Pathology, Regina Elena National Cancer, Institute, IRCCS, Rome, Italy
| | - Mario Patrizio
- Department of Drug Research and Medicine Evaluation, Istituto Superiore di Sanita', Rome, Italy
| | | | - Michele Gallucci
- Department of Urology, Regina Elena National Cancer Institute, IRCCS, Rome, Italy
| | - Mauro Piacentini
- Laboratory of Cell Biology and Electron Microscopy, National Institute for Infectious Diseases I.R.C.C.S. 'L. Spallanzani', Rome, Italy.,Department of Biology, University of Rome 'Tor Vergata', Rome, Italy
| | - Walter Malorni
- Department of Drug Research and Medicine Evaluation, Istituto Superiore di Sanita', Rome, Italy. .,Istituto San Raffaele Pisana, Rome, Italy.
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Grasso S, Pereira GJS, Palmeira-Dos-Santos C, Calgarotto AK, Martínez-Lacaci I, Ferragut JA, Smaili SS, Bincoletto C. Autophagy regulates Selumetinib (AZD6244) induced-apoptosis in colorectal cancer cells. Eur J Med Chem 2016; 122:611-618. [PMID: 27448918 DOI: 10.1016/j.ejmech.2016.06.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 06/23/2016] [Accepted: 06/24/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE As Selumetinib is a MEK1/2 inhibitor that has gained interest as an anti-tumor agent, the present study was designed to investigate autophagy involvement on Selumetinib-induced apoptosis in colorectal cancer (CRC) cells. METHODS CRC cells death and cycle studies were assessed by AnnexinV-FITC and PI staining, respectively. Autophagy flux was analysed by Western Blot (LC3II and p62 protein levels) and retroviral infection of SW480 cells for siBecn1 RNA interference experiments. Confocal microscopy was used to determine mCherry-EGFP-LC3 distribution. KEY FINDINGS The Selumetinib effects were concentration-dependent in SW480 cell line. Whereas 1 μM exerted an arrest in the cell cycle (G1 phase), higher concentrations (10 μM) induced cell death, which was accompanied by autophagy blockage in its last stages. Autophagy induction by Rapamycin (RAPA) increased cell survival, whereas pharmacology autophagy inhibition by Bafilomycin A1 (BAF), Chloroquine (CQ) or 3-Methyladenine (3-MA) increased Selumetinib-induced CRC cells death. CONCLUSIONS Altogether, these results suggest that autophagy plays a fundamental role in CRC cells response to Selumetinib. In addition, the combination of Selumetinib with autophagy inhibitors may be a useful therapeutic strategy to enhance its activity against colorectal tumours.
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Affiliation(s)
- Silvina Grasso
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, 03202 Elche, Alicante, Spain; Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Gustavo J S Pereira
- Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Caroline Palmeira-Dos-Santos
- Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Andrana K Calgarotto
- Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Isabel Martínez-Lacaci
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, 03202 Elche, Alicante, Spain; Unidad AECC de Investigación Traslacional en Cáncer, Hospital Universitario Virgen de la Arrixaca, Instituto Murciano de Investigación Biosanitaria, 30120 Murcia, Spain
| | - Jose Antonio Ferragut
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, 03202 Elche, Alicante, Spain
| | - Soraya S Smaili
- Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
| | - Claudia Bincoletto
- Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
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Zhuang L, Ma Y, Wang Q, Zhang J, Zhu C, Zhang L, Xu X. Atg3 Overexpression Enhances Bortezomib-Induced Cell Death in SKM-1 Cell. PLoS One 2016; 11:e0158761. [PMID: 27391105 PMCID: PMC4938461 DOI: 10.1371/journal.pone.0158761] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/21/2016] [Indexed: 12/19/2022] Open
Abstract
Background Myelodysplastic syndrome (MDS) is a group of heterogeneous hematopoietic stem cell malignancies with a high risk of transformation into acute myeloid leukemia (AML). Clonal evolutions are significantly associated with transformation to AML. According to a gene expression microarray, atg3 is downregulated in MDS patients progressing to leukemia, but less is known about the function of Atg3 in the survival and death of MSD/AML cells. Moreover, the role of autophagy as a result of bortezomib treatment is controversial. The current study was designed to investigate the function of Atg3 in SKM-1 cells and to study the effect of Atg3 on cell viability and cell death following bortezomib treatment. Methods Four leukemia cell lines (SKM-1, THP-1, NB4 and K562) and two healthy patients’ bone marrow cells were analyzed for Atg3 expression via qRT-PCR and Western blotting analysis. The role of Atg3 in SKM-1 cell survival and cell death was analyzed by CCK-8 assay, trypan blue exclusion assay, DAPI staining and Annexin V/PI dual staining with or without bortezomib treatment. Western blotting analysis was used to detect proteins in autophagic and caspase signaling pathways. Electron microscopy was used to observe ultrastructural changes after Atg3 overexpression. Results Downregulation of Atg3 expression was detected in four leukemia cell lines compared with healthy bone marrow cells. Atg3 mRNA was significantly decreased in MDS patients’ bone marrow cells. Overexpression of Atg3 in SKM-1 cells resulted in AKT-mTOR-dependent autophagy, a significant reduction in cell proliferation and increased cell death, which could be overcome by the autophagy inhibitor 3-MA. SKM-1 cells overexpressing Atg3 were hypersensitive to bortezomib treatment at different concentrations via autophagic cell death and enhanced sensitivity to apoptosis in the SKM-1 cell line. Following treatment with 3-MA, the sensitivity of Atg3-overexpressing cells to bortezomib treatment was reduced. Atg3 knockdown blocked cell growth inhibition and cell death induced by bortezomib. Conclusion Our preliminary study of Atg3 in the high-risk MDS cell line suggests that Atg3 might be possibly a critical regulator of autophagic cell death and a gene target for therapeutic interventions in MDS.
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Affiliation(s)
- Lin Zhuang
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yan Ma
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qian Wang
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jing Zhang
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chen Zhu
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lu Zhang
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaoping Xu
- Department of Hematology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- * E-mail:
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226
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Deloch L, Derer A, Hartmann J, Frey B, Fietkau R, Gaipl US. Modern Radiotherapy Concepts and the Impact of Radiation on Immune Activation. Front Oncol 2016; 6:141. [PMID: 27379203 PMCID: PMC4913083 DOI: 10.3389/fonc.2016.00141] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/23/2016] [Indexed: 12/12/2022] Open
Abstract
Even though there is extensive research carried out in radiation oncology, most of the clinical studies focus on the effects of radiation on the local tumor tissue and deal with normal tissue side effects. The influence of dose fractionation and timing particularly with regard to immune activation is not satisfactorily investigated so far. This review, therefore, summarizes current knowledge on concepts of modern radiotherapy (RT) and evaluates the potential of RT for immune activation. Focus is set on radiation-induced forms of tumor cell death and consecutively the immunogenicity of the tumor cells. The so-called non-targeted, abscopal effects can contribute to anti-tumor responses in a specific and systemic manner and possess the ability to target relapsing tumor cells as well as metastases. The impact of distinct RT concepts on immune activation is outlined and pre-clinical evidence and clinical observations on RT-induced immunity will be discussed. Knowledge on the radiosensitivity of immune cells as well as clinical evidence for enhanced immunity after RT will be considered. While stereotactic ablative body radiotherapy seem to have a beneficial outcome over classical RT fractionation in pre-clinical animal models, in vitro model systems suggest an advantage for classical fractionated RT for immune activation. Furthermore, the optimal approach may differ based on the tumor site and/or genetic signature. These facts highlight that clinical trials are urgently needed to identify whether high-dose RT is superior to induce anti-tumor immune responses compared to classical fractionated RT and in particular how the outcome is when RT is combined with immunotherapy in selected tumor entities.
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Affiliation(s)
- Lisa Deloch
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany
| | - Anja Derer
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany
| | - Josefin Hartmann
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany
| | - Benjamin Frey
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany
| | - Rainer Fietkau
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany
| | - Udo S Gaipl
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg , Erlangen , Germany
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227
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Abstract
The remarkable metabolic differences between cancer cells and normal cells result in the potential for targeted cancer therapy. The upregulation of glutaminolysis provides energetic advantages to cancer cells. The recently described link between glutaminolysis and autophagy, mediated by MTORC1, may constitute an attractive target for therapeutic strategies. A combination of therapies targeting simultane-ously cell signaling, cancer metabolism, and autophagy can solve therapy resistance and tumor relapse problems, commonly observed in patients treated with most of the current targeted therapies. In this review we summarize the mechanistic link between glutaminolysis and autophagy, and discuss the impacts of these processes on cancer progression and the potential for therapeutic intervention.
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228
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Dou Q, Chen HN, Wang K, Yuan K, Lei Y, Li K, Lan J, Chen Y, Huang Z, Xie N, Zhang L, Xiang R, Nice EC, Wei Y, Huang C. Ivermectin Induces Cytostatic Autophagy by Blocking the PAK1/Akt Axis in Breast Cancer. Cancer Res 2016; 76:4457-69. [PMID: 27302166 DOI: 10.1158/0008-5472.can-15-2887] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 05/06/2016] [Indexed: 12/09/2022]
Affiliation(s)
- Qianhui Dou
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Hai-Ning Chen
- Department of Gastrointestinal Surgery, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Kui Wang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China. Key Laboratory of Tropical Diseases and Translational Medicine of Ministry of Education & Department of Neurology, the Affiliated Hospital of Hainan Medical College, Haikou, China
| | - Kefei Yuan
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Yunlong Lei
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing, P.R. China
| | - Kai Li
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Jiang Lan
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China. Key Laboratory of Tropical Diseases and Translational Medicine of Ministry of Education & Department of Neurology, the Affiliated Hospital of Hainan Medical College, Haikou, China
| | - Yan Chen
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Zhao Huang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Na Xie
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Lu Zhang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Rong Xiang
- School of Medicine/Collaborative Innovation Center of Biotherapy, Nankai University, Tianjin, China
| | - Edouard C Nice
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Yuquan Wei
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China
| | - Canhua Huang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, P.R. China. Key Laboratory of Tropical Diseases and Translational Medicine of Ministry of Education & Department of Neurology, the Affiliated Hospital of Hainan Medical College, Haikou, China.
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Zhang LD, Liu Z, Liu H, Ran DM, Guo JH, Jiang B, Wu YL, Gao FH. Oridonin enhances the anticancer activity of NVP-BEZ235 against neuroblastoma cells in vitro and in vivo through autophagy. Int J Oncol 2016; 49:657-65. [PMID: 27278249 DOI: 10.3892/ijo.2016.3557] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 04/09/2016] [Indexed: 11/06/2022] Open
Abstract
The aberrant activation of PI3K/Akt/mTOR signaling pathway plays an important role in the oncogenesis, prognosis and chemotherapy resistance of neuroblastoma. However, NVP-BEZ235, a potent dual PI3K and mTOR inhibitor have not shown beneficial effects on neuroblastoma especially in terms of apoptosis induction as a single agent. We therefore attempted to explore an effective combination regimen to enhance the anticancer activity of NVP-BEZ235. Interestingly, we found that oridonin, a natural biologically active compound extracted from the Chinese medicinal herb Rabdosia rubescens, combined with NVP-BEZ235 markedly induced apoptosis of neuroblastoma cells. Notably, the synergistic activation of the apoptotic pathway was accompanied with enhanced autophagy as evidenced by significant decreased p62 expression as well as upregulated conversion of LC3-II. Suppression of the Beclin-1, a core component of the autophagy machinery, by means of shRNA resulted in diminished synergistic antitumor effect. Furthermore, the co-treatment with oridonin and NVP-BEZ235 was also much more effective than either agent alone in inhibiting the growth of neuroblastoma xenografts and in inducing tumor cells apoptosis. Taken together, our results suggest that the combination of NVP-BEZ235 and oridonin is a novel and potential strategy for neuroblastoma therapy.
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Affiliation(s)
- Li-Di Zhang
- Institute of Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, P.R. China
| | - Zhen Liu
- Institute of Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, P.R. China
| | - Hua Liu
- Department of Gastroenterology, The Tenth Hospital Affiliated to Tongji University, Shanghai 200072, P.R. China
| | - Dong-Mei Ran
- Department of Pathology, The Sixth People's Hospital of Zhengzhou City, Zhengzhou, Henan 450015, P.R. China
| | - Jia-Hui Guo
- Institute of Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, P.R. China
| | - Bin Jiang
- Institute of Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, P.R. China
| | - Ying-Li Wu
- Hongqiao International Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Chemical Biology Division of Shanghai Universities E-Institutes, Key Laboratory of Cell Differentiation and Apoptosis of the Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Feng-Hou Gao
- Institute of Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, P.R. China
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DNA double-strand-break repair in higher eukaryotes and its role in genomic instability and cancer: Cell cycle and proliferation-dependent regulation. Semin Cancer Biol 2016; 37-38:51-64. [DOI: 10.1016/j.semcancer.2016.03.003] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 03/11/2016] [Accepted: 03/21/2016] [Indexed: 12/18/2022]
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231
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Patil MD, Bhaumik J, Babykutty S, Banerjee UC, Fukumura D. Arginine dependence of tumor cells: targeting a chink in cancer's armor. Oncogene 2016; 35:4957-72. [PMID: 27109103 DOI: 10.1038/onc.2016.37] [Citation(s) in RCA: 173] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 02/02/2016] [Accepted: 02/02/2016] [Indexed: 12/14/2022]
Abstract
Arginine, one among the 20 most common natural amino acids, has a pivotal role in cellular physiology as it is being involved in numerous cellular metabolic and signaling pathways. Dependence on arginine is diverse for both tumor and normal cells. Because of decreased expression of argininosuccinate synthetase and/or ornithine transcarbamoylase, several types of tumor are auxotrophic for arginine. Deprivation of arginine exploits a significant vulnerability of these tumor cells and leads to their rapid demise. Hence, enzyme-mediated arginine depletion is a potential strategy for the selective destruction of tumor cells. Arginase, arginine deiminase and arginine decarboxylase are potential enzymes that may be used for arginine deprivation therapy. These arginine catabolizing enzymes not only reduce tumor growth but also make them susceptible to concomitantly administered anti-cancer therapeutics. Most of these enzymes are currently under clinical investigations and if successful will potentially be advanced as anti-cancer modalities.
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Affiliation(s)
- M D Patil
- Department of Pharmaceutical Technology (Biotechnology), National Institute of Pharmaceutical Education and Research, Punjab, India
| | - J Bhaumik
- Department of Pharmaceutical Technology (Biotechnology), National Institute of Pharmaceutical Education and Research, Punjab, India
| | - S Babykutty
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - U C Banerjee
- Department of Pharmaceutical Technology (Biotechnology), National Institute of Pharmaceutical Education and Research, Punjab, India
| | - D Fukumura
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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232
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Secreted Cyclic Di-GMP Induces Stalk Cell Differentiation in the Eukaryote Dictyostelium discoideum. J Bacteriol 2016; 198:27-31. [PMID: 26013485 PMCID: PMC4686194 DOI: 10.1128/jb.00321-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Cyclic di-GMP (c-di-GMP) is currently recognized as the most widely used intracellular signal molecule in prokaryotes, but roles in eukaryotes were only recently discovered. In the social amoeba Dictyostelium discoideum, c-di-GMP, produced by a prokaryote-type diguanylate cyclase, induces the differentiation of stalk cells, thereby enabling the formation of spore-bearing fruiting bodies. In this review, we summarize the currently known mechanisms that control the major life cycle transitions of Dictyostelium and focus particularly on the role of c-di-GMP in stalk formation. Stalk cell differentiation has characteristics of autophagic cell death, a process that also occurs in higher eukaryotes. We discuss the respective roles of c-di-GMP and of another signal molecule, differentiation-inducing factor 1, in autophagic cell death in vitro and in stalk formation in vivo.
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233
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Mutant p53 proteins counteract autophagic mechanism sensitizing cancer cells to mTOR inhibition. Mol Oncol 2016; 10:1008-29. [PMID: 27118659 DOI: 10.1016/j.molonc.2016.04.001] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/01/2016] [Accepted: 04/04/2016] [Indexed: 11/23/2022] Open
Abstract
Mutations in TP53 gene play a pivotal role in tumorigenesis and cancer development. Here, we report that gain-of-function mutant p53 proteins inhibit the autophagic pathway favoring antiapoptotic effects as well as proliferation of pancreas and breast cancer cells. We found that mutant p53 significantly counteracts the formation of autophagic vesicles and their fusion with lysosomes throughout the repression of some key autophagy-related proteins and enzymes as BECN1 (and P-BECN1), DRAM1, ATG12, SESN1/2 and P-AMPK with the concomitant stimulation of mTOR signaling. As a paradigm of this mechanism, we show that atg12 gene repression was mediated by the recruitment of the p50 NF-κB/mutant p53 protein complex onto the atg12 promoter. Either mutant p53 or p50 NF-κB depletion downregulates atg12 gene expression. We further correlated the low expression levels of autophagic genes (atg12, becn1, sesn1, and dram1) with a reduced relapse free survival (RFS) and distant metastasis free survival (DMFS) of breast cancer patients carrying TP53 gene mutations conferring a prognostic value to this mutant p53-and autophagy-related signature. Interestingly, the mutant p53-driven mTOR stimulation sensitized cancer cells to the treatment with the mTOR inhibitor everolimus. All these results reveal a novel mechanism through which mutant p53 proteins promote cancer cell proliferation with the concomitant inhibition of autophagy.
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234
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Pruitt HC, Devine DJ, Samant RS. Roles of N-Myc and STAT interactor in cancer: From initiation to dissemination. Int J Cancer 2016; 139:491-500. [PMID: 26874464 PMCID: PMC5069610 DOI: 10.1002/ijc.30043] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 01/20/2016] [Accepted: 02/09/2016] [Indexed: 12/22/2022]
Abstract
N‐myc & STAT Interactor, NMI, is a protein that has mostly been studied for its physical interactions with transcription factors that play critical roles in tumor growth, progression and metastasis. NMI is an inducible protein, thus its intracellular levels and location can vary dramatically, influencing a diverse array of cellular functions in a context‐dependent manner. The physical interactions of NMI with its binding partners have been linked to many aspects of tumor biology including DNA damage response, cell death, epithelial‐to‐mesenchymal transition and stemness. Thus, discovering more details about the function(s) of NMI could reveal key insights into how transcription factors like c‐Myc, STATs and BRCA1 are contextually regulated. Although a normal, physiological function of NMI has not yet been discovered, it has potential roles in pathologies ranging from viral infection to cancer. This review provides a timely perspective of the unfolding roles of NMI with specific focus on cancer progression and metastasis.
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Affiliation(s)
- Hawley C Pruitt
- Department of Pathology and Comprehensive Cancer Center, University of Alabama at Birmingham, Alabama, AL
| | | | - Rajeev S Samant
- Department of Pathology and Comprehensive Cancer Center, University of Alabama at Birmingham, Alabama, AL
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235
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The BH3 Mimetic Obatoclax Accumulates in Lysosomes and Causes Their Alkalinization. PLoS One 2016; 11:e0150696. [PMID: 26950068 PMCID: PMC4780728 DOI: 10.1371/journal.pone.0150696] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 02/17/2016] [Indexed: 11/25/2022] Open
Abstract
Obatoclax belongs to a class of compounds known as BH3 mimetics which function as antagonists of Bcl-2 family apoptosis regulators. It has undergone extensive preclinical and clinical evaluation as a cancer therapeutic. Despite this, it is clear that obatoclax has additional pharmacological effects that contribute to its cytotoxic activity. It has been claimed that obatoclax, either alone or in combination with other molecularly targeted therapeutics, induces an autophagic form of cell death. In addition, obatoclax has been shown to inhibit lysosomal function, but the mechanism of this has not been elucidated. We have evaluated the mechanism of action of obatoclax in eight ovarian cancer cell lines. Consistent with its function as a BH3 mimetic, obatoclax induced apoptosis in three cell lines. However, in the remaining cell lines another form of cell death was evident because caspase activation and PARP cleavage were not observed. Obatoclax also failed to show synergy with carboplatin and paclitaxel, chemotherapeutic agents which we have previously shown to be synergistic with authentic Bcl-2 family antagonists. Obatoclax induced a profound accumulation of LC-3 but knockdown of Atg-5 or beclin had only minor effects on the activity of obatoclax in cell growth assays suggesting that the inhibition of lysosomal function rather than stimulation of autophagy may play a more prominent role in these cells. To evaluate how obatoclax inhibits lysosomal function, confocal microscopy studies were conducted which demonstrated that obatoclax, which contains two basic pyrrole groups, accumulates in lysosomes. Studies using pH sensitive dyes demonstrated that obatoclax induced lysosomal alkalinization. Furthermore, obatoclax was synergistic in cell growth/survival assays with bafilomycin and chloroquine, two other drugs which cause lysosomal alkalinization. These studies explain, for the first time, how obatoclax inhibits lysosomal function and suggest that lysosomal alkalinization contributes to the cytotoxic activity of obatoclax.
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236
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Yan Y, Xu Z, Dai S, Qian L, Sun L, Gong Z. Targeting autophagy to sensitive glioma to temozolomide treatment. J Exp Clin Cancer Res 2016; 35:23. [PMID: 26830677 PMCID: PMC4736617 DOI: 10.1186/s13046-016-0303-5] [Citation(s) in RCA: 219] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 01/28/2016] [Indexed: 02/08/2023] Open
Abstract
Temozolomide (TMZ), an alkylating agent, is widely used for treating primary and recurrent high-grade gliomas. However, the efficacy of TMZ is often limited by the development of resistance. Recently, studies have found that TMZ treatment could induce autophagy, which contributes to therapy resistance in glioma. To enhance the benefit of TMZ in the treatment of glioblastomas, effective combination strategies are needed to sensitize glioblastoma cells to TMZ. In this regard, as autophagy could promote cell survival or autophagic cell death, modulating autophagy using a pharmacological inhibitor, such as chloroquine, or an inducer, such as rapamycin, has received considerably more attention. To understand the effectiveness of regulating autophagy in glioblastoma treatment, this review summarizes reports on glioblastoma treatments with TMZ and autophagic modulators from in vitro and in vivo studies, as well as clinical trials. Additionally, we discuss the possibility of using autophagy regulatory compounds that can sensitive TMZ treatment as a chemotherapy for glioma treatment.
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Affiliation(s)
- Yuanliang Yan
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Institute of Hospital Pharmacy, Central South University, Changsha, 410008, China.
| | - Zhijie Xu
- Department of Pathology, Xiangya Hospital, Central South University, Changsha, 410008, China.
| | - Shuang Dai
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Institute of Hospital Pharmacy, Central South University, Changsha, 410008, China.
| | - Long Qian
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Institute of Hospital Pharmacy, Central South University, Changsha, 410008, China.
| | - Lunquan Sun
- Center for Molecular Medicine, Xiangya Hospital, Key Laboratory of Molecular Radiation Oncology of Hunan Province, Central South University, Changsha, 410008, China.
| | - Zhicheng Gong
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Institute of Hospital Pharmacy, Central South University, Changsha, 410008, China.
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237
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Tao S, Rojo de la Vega M, Quijada H, Wondrak GT, Wang T, Garcia JGN, Zhang DD. Bixin protects mice against ventilation-induced lung injury in an NRF2-dependent manner. Sci Rep 2016; 6:18760. [PMID: 26729554 PMCID: PMC4700431 DOI: 10.1038/srep18760] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 08/26/2015] [Indexed: 12/19/2022] Open
Abstract
Mechanical ventilation (MV) is a therapeutic intervention widely used in the clinic to assist patients that have difficulty breathing due to lung edema, trauma, or general anesthesia. However, MV causes ventilator-induced lung injury (VILI), a condition characterized by increased permeability of the alveolar-capillary barrier that results in edema, hemorrhage, and neutrophil infiltration, leading to exacerbated lung inflammation and oxidative stress. This study explored the feasibility of using bixin, a canonical NRF2 inducer identified during the current study, to ameliorate lung damage in a murine VILI model. In vitro, bixin was found to activate the NRF2 signaling pathway through blockage of ubiquitylation and degradation of NRF2 in a KEAP1-C151 dependent manner; intraperitoneal (IP) injection of bixin led to pulmonary upregulation of the NRF2 response in vivo. Remarkably, IP administration of bixin restored normal lung morphology and attenuated inflammatory response and oxidative DNA damage following MV. This observed beneficial effect of bixin derived from induction of the NRF2 cytoprotective response since it was only observed in Nrf2+/+ but not in Nrf2−/− mice. This is the first study providing proof-of-concept that NRF2 activators can be developed into pharmacological agents for clinical use to prevent patients from lung injury during MV treatment.
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Affiliation(s)
- Shasha Tao
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA
| | | | - Hector Quijada
- Arizona Respiratory Center and Department of Medicine, University of Arizona, Tucson, AZ 85721
| | - Georg T Wondrak
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA.,Arizona Cancer Center, University of Arizona, 1515 North Campbell Avenue, Tucson, AZ 85724, USA
| | - Ting Wang
- Arizona Respiratory Center and Department of Medicine, University of Arizona, Tucson, AZ 85721
| | - Joe G N Garcia
- Arizona Respiratory Center and Department of Medicine, University of Arizona, Tucson, AZ 85721
| | - Donna D Zhang
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA.,Arizona Cancer Center, University of Arizona, 1515 North Campbell Avenue, Tucson, AZ 85724, USA
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238
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Gyurászová K, Mikeš J, Halaburková A, Jendželovský R, Fedoročko P. YM155, a small molecule inhibitor of survivin expression, sensitizes cancer cells to hypericin-mediated photodynamic therapy. Photochem Photobiol Sci 2016; 15:812-21. [DOI: 10.1039/c5pp00438a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Here we show for the first time that the repression of survivin expression by YM155 is effective in sensitizing cancer cells to HY-PDT, as measured by the decrease in cell viability and induction of apoptosis.
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Affiliation(s)
- Katarína Gyurászová
- Institute of Biology and Ecology
- Faculty of Science
- Pavol Jozef Šafárik University in Košice
- Košice
- Slovakia
| | - Jaromír Mikeš
- Institute of Biology and Ecology
- Faculty of Science
- Pavol Jozef Šafárik University in Košice
- Košice
- Slovakia
| | - Andrea Halaburková
- Institute of Biology and Ecology
- Faculty of Science
- Pavol Jozef Šafárik University in Košice
- Košice
- Slovakia
| | - Rastislav Jendželovský
- Institute of Biology and Ecology
- Faculty of Science
- Pavol Jozef Šafárik University in Košice
- Košice
- Slovakia
| | - Peter Fedoročko
- Institute of Biology and Ecology
- Faculty of Science
- Pavol Jozef Šafárik University in Košice
- Košice
- Slovakia
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239
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AT-101 simultaneously triggers apoptosis and a cytoprotective type of autophagy irrespective of expression levels and the subcellular localization of Bcl-xL and Bcl-2 in MCF7 cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:499-509. [PMID: 26721623 DOI: 10.1016/j.bbamcr.2015.12.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 12/15/2015] [Accepted: 12/17/2015] [Indexed: 12/30/2022]
Abstract
The effects of autophagy on cell death are highly contextual and either beneficial or deleterious. One prime example for this dual function of autophagy is evidenced by the cell responses to the BH3 mimetic AT-101 that is known to induce either apoptotic or autophagy-dependent cell death in different settings. Based on previous reports, we hypothesized that the expression levels of pro-survival Bcl-2 family members may be key determinants for the respective death mode induced by AT-101. Here we investigated the role of autophagy in the response of MCF7 breast cancer cells to AT-101. AT-101 treatment induced a prominent conversion of LC3-I to LC3-II and apoptotic cell death characterized by the appearance of Annexin-positive/PI-negative early apoptotic cells and PARP cleavage. Inhibition of the autophagy pathway, either through application of 3-MA or by lentiviral knockdown of ATG5, strongly potentiated cell death, indicating a pro-survival function of autophagy. Overexpression of wild type Bcl-xL significantly diminished the net amount of AT-101-induced cell death, but failed to alter the death-enhancing effects of the ATG5 knockdown. This was also observed with the organelle-specific variants Bcl-xL-ActA and Bcl-2-ActA (mitochondrial) as well as Bcl-xL-cb5 and Bcl-2-cb5 (ER) which all reduced AT-101-induced cell death, but did not affect the death-enhancing effects of 3-MA. Collectively, our data indicate that in apoptosis-proficient MCF7 cells, AT-101 triggers Bcl-2- and Bcl-xL-dependent apoptosis and a cytoprotective autophagy response that is independent of the expression and subcellular localization of Bcl-xL and Bcl-2.
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240
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Lu Y, Zhang R, Liu S, Zhao Y, Gao J, Zhu L. ZT-25, a new vacuolar H(+)-ATPase inhibitor, induces apoptosis and protective autophagy through ROS generation in HepG2 cells. Eur J Pharmacol 2015; 771:130-8. [PMID: 26689625 DOI: 10.1016/j.ejphar.2015.12.026] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 12/06/2015] [Accepted: 12/11/2015] [Indexed: 12/29/2022]
Abstract
The vacuolar H(+)-ATPase (V-ATPase) has recently been proposed as a key target for new strategies in cancer treatment. Our previous work has proved that diphyllin glycoside is a novel inhibitor of V-ATPase. Here the cytotoxic effects of ZT-25, the most potent diphyllin glycoside derivatives, were studied and some of the underlying mechanisms were elucidated. ZT-25 displayed strong cytotoxicity on several cancer cell lines and relatively low cytotoxicity on human fetal hepatic cells (WRL-68) at submicromolar concentrations. In human hepatoma cells HepG2, ZT-25 induced G1/G0 phase arrest and apoptosis, as well as mitochondrial membrane potential (MMP) dissipation and ATP depletion. Furthermore, Bcl-2 protein decreased, while Bax protein and cleaved caspase-3 protein increased upon ZT-25 treatment. Benzyloxycarbony (Cbz)-l-Val-Ala-Asp (OMe)-fluoromethylketone (Z-VAD-FMK), a well-known pan-caspase inhibitor, attenuated ZT-25-induced cell death, suggesting the involvement of caspase-dependent pathway. Intriguingly, ZT-25 induced autophagy in HepG2 cells as characterized by increased the conversion of LC3 I to LC3 II, Beclin-1 expression and autophagosome formation. Meanwhile, p-mTOR expression was decreased which indicated that ZT-25-induced autophagy might be mediated through the suppression of mTOR pathway. Inhibition of autophagy by 3-methyladenine (3-MA) and chloroquine (CQ) obviously promoted ZT-25-induced cell death, suggesting the protective role of autophagy. Increased intracellular ROS level was found to be the early event in ZT-25-treated HepG2 cells. Inhibition of ROS generation by N-acetyl-l-cysteine (NAC) attenuated ZT-25-induced cell death and autophagy. Together, these results provide key insights into the ZT-25-induced cytotoxicity in HepG2 cells, which will have a great impact on the further development of diphyllin derivatives.
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Affiliation(s)
- Yapeng Lu
- School of Medicine, Jiangsu University, Zhenjiang 212013, China; Institute of Nautical Medicine, Nantong University, Nantong 226019, China
| | - Rui Zhang
- Department of Neurology, Deji Hospital, Shanghai 200331, China
| | - Siyuan Liu
- Institute of Nautical Medicine, Nantong University, Nantong 226019, China
| | - Yu Zhao
- Institute of Nautical Medicine, Nantong University, Nantong 226019, China
| | - Jing Gao
- School of Pharmacy, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China.
| | - Li Zhu
- Institute of Nautical Medicine, Nantong University, Nantong 226019, China.
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241
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Zhang L, Wang K, Lei Y, Li Q, Nice EC, Huang C. Redox signaling: Potential arbitrator of autophagy and apoptosis in therapeutic response. Free Radic Biol Med 2015; 89:452-65. [PMID: 26454086 DOI: 10.1016/j.freeradbiomed.2015.08.030] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 08/27/2015] [Accepted: 08/31/2015] [Indexed: 02/05/2023]
Abstract
Redox signaling plays important roles in the regulation of cell death and survival in response to cancer therapy. Autophagy and apoptosis are discrete cellular processes mediated by distinct groups of regulatory and executioner molecules, and both are thought to be cellular responses to various stress conditions including oxidative stress, therefore controlling cell fate. Basic levels of reactive oxygen species (ROS) may function as signals to promote cell proliferation and survival, whereas increase of ROS can induce autophagy and apoptosis by damaging cellular components. Growing evidence in recent years argues for ROS that below detrimental levels acting as intracellular signal transducers that regulate autophagy and apoptosis. ROS-regulated autophagy and apoptosis can cross-talk with each other. However, how redox signaling determines different cell fates by regulating autophagy and apoptosis remains unclear. In this review, we will focus on understanding the delicate molecular mechanism by which autophagy and apoptosis are finely orchestrated by redox signaling and discuss how this understanding can be used to develop strategies for the treatment of cancer.
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Affiliation(s)
- Lu Zhang
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, 610041, P.R. China; Department of Neurology, the Affiliated Hospital of Hainan Medical College, Haikou, 570102, P.R. China
| | - Kui Wang
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, 610041, P.R. China
| | - Yunlong Lei
- Department of Biochemistry and Molecular Biology, and Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Qifu Li
- Department of Neurology, the Affiliated Hospital of Hainan Medical College, Haikou, 570102, P.R. China
| | - Edouard Collins Nice
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Canhua Huang
- State Key Laboratory for Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center of Biotherapy, Chengdu, 610041, P.R. China.
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242
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Villa E, Ricci JE. How does metabolism affect cell death in cancer? FEBS J 2015; 283:2653-60. [PMID: 26498911 DOI: 10.1111/febs.13570] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 10/14/2015] [Accepted: 10/20/2015] [Indexed: 12/22/2022]
Abstract
In cancer research, identifying a specificity of tumor cells compared with 'normal' proliferating cells for targeted therapy is often considered the Holy Grail for researchers and clinicians. Although diverse in origin, most cancer cells share characteristics including the ability to escape cell death mechanisms and the utilization of different methods of energy production. In the current paradigm, aerobic glycolysis is considered the central metabolic characteristic of cancer cells (Warburg effect). However, recent data indicate that cancer cells also show significant changes in other metabolic pathways. Indeed, it was recently suggested that Kreb's cycle, pentose phosphate pathway intermediates, and essential and nonessential amino acids have key roles. Renewed interest in the fact that cancer cells have to reprogram their metabolism in order to proliferate or resist treatment must take into consideration the ability of tumor cells to adapt their metabolism to the local microenvironment (low oxygen, low nutrients). This variety of metabolic sources might be either a strength, resulting in infinite possibilities for adaptation and increased ability to resist chemotherapy-induced death, or a weakness that could be targeted to kill cancer cells. Here, we discuss recent insights showing how energetic metabolism may regulate cell death and how this might be relevant for cancer treatment.
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Affiliation(s)
- Elodie Villa
- Inserm, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), équipe 'contrôle métabolique des morts cellulaires', Nice, France.,Faculté de Médecine, Université de Nice-Sophia-Antipolis, Nice, France
| | - Jean-Ehrland Ricci
- Inserm, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), équipe 'contrôle métabolique des morts cellulaires', Nice, France.,Faculté de Médecine, Université de Nice-Sophia-Antipolis, Nice, France.,Département d'Anesthésie Réanimation, Centre Hospitalier Universitaire de Nice, Nice, France
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243
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Jiang T, Harder B, Rojo de la Vega M, Wong PK, Chapman E, Zhang DD. p62 links autophagy and Nrf2 signaling. Free Radic Biol Med 2015; 88:199-204. [PMID: 26117325 PMCID: PMC4628872 DOI: 10.1016/j.freeradbiomed.2015.06.014] [Citation(s) in RCA: 404] [Impact Index Per Article: 44.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Revised: 06/09/2015] [Accepted: 06/10/2015] [Indexed: 12/15/2022]
Abstract
The Nrf2-Keap1-ARE pathway is a redox and xenobiotic sensitive signaling axis that functions to protect cells against oxidative stress, environmental toxicants, and harmful chemicals through the induction of cytoprotective genes. To enforce strict regulation, cells invest a great deal of energy into the maintenance of the Nrf2 pathway to ensure rapid induction upon cellular insult and rapid return to basal levels once the insult is mitigated. Because of the protective role of Nrf2 transcriptional programs, controlled activation of the pathway has been recognized as a means for chemoprevention. On the other hand, constitutive activation of Nrf2, due to somatic mutations of genes that control Nrf2 degradation, promotes carcinogenesis and imparts chemoresistance to cancer cells. Autophagy, a bulk protein degradation process, is another tightly regulated complex cellular process that functions as a cellular quality control system to remove damaged proteins or organelles. Low cellular nutrient levels can also activate autophagy, which acts to restore metabolic homeostasis through the degradation of macromolecules to provide nutrients. Recently, these two cellular pathways were shown to intersect through the direct interaction between p62 (an autophagy adaptor protein) and Keap1 (the Nrf2 substrate adaptor for the Cul3 E3 ubiquitin ligase). Dysregulation of autophagy was shown to result in prolonged Nrf2 activation in a p62-dependent manner. In this review, we will discuss the progress that has been made in dissecting the intersection of these two pathways and the potential tumor-promoting role of prolonged Nrf2 activation.
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Affiliation(s)
- Tao Jiang
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA
| | - Bryan Harder
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA
| | | | - Pak K Wong
- Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, AZ 85721, USA
| | - Eli Chapman
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA
| | - Donna D Zhang
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA; Arizona Cancer Center, University of Arizona, Tucson, Arizona 85724, USA.
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244
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Buttigliero C, Tucci M, Bertaglia V, Vignani F, Bironzo P, Di Maio M, Scagliotti GV. Understanding and overcoming the mechanisms of primary and acquired resistance to abiraterone and enzalutamide in castration resistant prostate cancer. Cancer Treat Rev 2015; 41:884-92. [PMID: 26342718 DOI: 10.1016/j.ctrv.2015.08.002] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 08/16/2015] [Accepted: 08/24/2015] [Indexed: 02/08/2023]
Abstract
In recent years, in castration resistant prostate cancer (CRPC), several new drugs have been approved that prolong overall survival, including enzalutamide and abiraterone, two new-generation hormonal therapies. Despite the demonstrated benefit of these agents, not all patients with CRPC are responsive to treatment, the gain in median progression-free survival with these therapies compared to standard of care is, rather disappointingly, still less than six months and the appearance of acquired resistance is almost universal. Approximately one third of patients treated with abiraterone and 25% of those treated with enzalutamide show primary resistance to these agents. Even if the mechanisms of resistance to these agents are not fully defined, many hypotheses are emerging, including systemic and intratumoral androgen biosynthesis up-regulation, androgen receptor (AR) gene mutations and amplifications, alteration of pathways involved in cross-talk with AR signaling, glucocorticoid receptor overexpression, neuroendocrine differentiation, immune system deregulation and others. The aim of this paper is to review currently available data about mechanisms of resistance to abiraterone and enzalutamide, and to discuss how these mechanisms could be potentially overcome through novel therapeutic agents.
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Affiliation(s)
- Consuelo Buttigliero
- Department of Oncology, Medical Oncology, University of Turin at San Luigi Hospital, Orbassano, Italy.
| | - Marcello Tucci
- Department of Oncology, Medical Oncology, University of Turin at San Luigi Hospital, Orbassano, Italy
| | - Valentina Bertaglia
- Department of Oncology, Medical Oncology, University of Turin at San Luigi Hospital, Orbassano, Italy
| | - Francesca Vignani
- Department of Oncology, Medical Oncology, University of Turin at San Luigi Hospital, Orbassano, Italy
| | - Paolo Bironzo
- Department of Oncology, Medical Oncology, University of Turin at San Luigi Hospital, Orbassano, Italy
| | - Massimo Di Maio
- Department of Oncology, Medical Oncology, University of Turin at San Luigi Hospital, Orbassano, Italy
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245
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Li HT, Zhao XZ, Zhang XR, Li G, Jia ZQ, Sun P, Wang JQ, Fan ZK, Lv G. Exendin-4 Enhances Motor Function Recovery via Promotion of Autophagy and Inhibition of Neuronal Apoptosis After Spinal Cord Injury in Rats. Mol Neurobiol 2015. [PMID: 26198566 DOI: 10.1007/s12035-015-9327-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Autophagy occurs prior to apoptosis and plays an important role in cell death regulation during spinal cord injury (SCI). This study aimed to determine the effects and potential mechanism of the glucagon-like peptide-1 (GLP-1) agonist extendin-4 (Ex-4) in SCI. Seventy-two male Sprague Dawley rats were randomly assigned to sham, SCI, 2.5 μg Ex-4, and 10 μg Ex-4 groups. To induce SCI, a 10-g iron rod was dropped from a 20-mm height to the spinal cord surface. Ex-4 was administered via intraperitoneal injection immediately after surgery. Motor function evaluation with the Basso Beattie Bresnahan (BBB) locomotor rating scale indicated significantly increased scores (p < 0.01) in the Ex-4-treated groups, especially 10 μg, which demonstrated the neuroprotective effect of Ex-4 after SCI. The light chain 3-II (LC3-II) and Beclin 1 protein expression determined via western blot and the number of autophagy-positive neurons via immunofluorescence double labeling were increased by Ex-4, which supports promotion of autophagy (p < 0.01). The caspase-3 protein level and neuronal apoptosis via transferase UTP nick end labeling (TUNEL)/NeuN/DAPI double labeling were significantly reduced in the Ex-4-treated groups, which indicates anti-apoptotic effects (p < 0.01). Finally, histological assessment via Nissl staining demonstrated the Ex-4 groups exhibited a significantly greater number of surviving neurons and less cavity (p < 0.01). To our knowledge, this is the first study to indicate that Ex-4 significantly enhances motor function in rats after SCI, and these effects are associated with the promotion of autophagy and inhibition of apoptosis.
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Affiliation(s)
- Hao-Tian Li
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China
| | - Xing-Zhang Zhao
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China
| | - Xin-Ran Zhang
- Postgraduate Training Base of General Hospital of Armed Police Forces, Liaoning Medical University, Beijing, 100039, China
| | - Gang Li
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China
| | - Zhi-Qiang Jia
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China
| | - Ping Sun
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China
| | - Ji-Quan Wang
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China
| | - Zhong-Kai Fan
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China.
| | - Gang Lv
- Department of Orthopaedics, The First Affiliated Hospital, Liaoning Medical University, Jinzhou, 121000, China.
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246
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Autophagy dysregulation and the fate of retinal ganglion cells in glaucomatous optic neuropathy. PROGRESS IN BRAIN RESEARCH 2015; 220:87-105. [PMID: 26497786 DOI: 10.1016/bs.pbr.2015.04.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Glaucoma is a neurodegenerative disease caused by the progressive apoptotic death of retinal ganglion cells (RGCs). The mechanisms leading to the RGC loss are still unknown but it is now clear that, besides elevated intraocular pressure (IOP), which is considered the main risk factor, other IOP-independent determinants are responsible for the development of the optic neuropathy. Autophagy is a highly conserved catabolic pathway by which cellular components are degraded through the lysosomes. Dysfunctional autophagic pathway has been associated with several neuropathological conditions and a considerable number of studies have proved autophagy as a potential target for pharmacological modulation to achieve neuroprotection. Here, we review the current literature bridging the degeneration of RGCs to alterations of the autophagic pathway; we also discuss the possible role of autophagy in the pathogenesis and progression of glaucoma in view of the future application of autophagy modulators for glaucoma therapy.
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247
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Loss of protein targeting to glycogen sensitizes human hepatocellular carcinoma cells towards glucose deprivation mediated oxidative stress and cell death. Biosci Rep 2015; 35:BSR20150090. [PMID: 26182369 PMCID: PMC4613675 DOI: 10.1042/bsr20150090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 05/01/2015] [Indexed: 01/01/2023] Open
Abstract
PTG is a protein that is critical for glycogen accumulation in various tissues such as the liver. Our present study shows that its loss sensitizes liver cancer cells towards metabolic and oxidative stress. Protein targeting to glycogen (PTG) is a ubiquitously expressed scaffolding protein that critically regulates glycogen levels in many tissues, including the liver, muscle and brain. However, its importance in transformed cells has yet to be explored in detail. Since recent studies have demonstrated an important role for glycogen metabolism in cancer cells, we decided to assess the effect of PTG levels on the ability of human hepatocellular carcinoma (HepG2) cells to respond to metabolic stress. Although PTG expression did not significantly affect the proliferation of HepG2 cells under normal culture conditions, we determined that PTG plays an important role during glucose deprivation. Overexpression of PTG protected cells from cell death in the absence of glucose, whereas knocking down PTG further promoted cytotoxicity, as measured by the release of lactate dehydrogenase (LDH) into the media. Additionally, we demonstrated that PTG attenuates glucose deprivation induced haeme oxygenase-1 (HO-1) expression, suggesting that PTG protects against glucose deprivation-induced oxidative stress. Indeed, treating cells with the antioxidant N-acetyl cysteine (NAC) rescued cells from cytotoxicity caused by glucose deprivation. Finally, we showed that loss of PTG resulted in enhanced autophagy. In control cells, glucose deprivation suppressed autophagy as determined by the increase in the levels of p62, an autophagy substrate. However, in knockdown cells, this suppression was relieved. Blockade of autophagy also attenuated cytotoxicity from glucose deprivation in PTG knockdown cells. Taken together, our findings identify a novel role for PTG in protecting hepatocellular carcinoma cells from metabolic stress, in part by regulating oxidative stress and autophagy.
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Emerging strategies to effectively target autophagy in cancer. Oncogene 2015; 35:1-11. [PMID: 25893285 DOI: 10.1038/onc.2015.99] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/18/2015] [Accepted: 02/18/2015] [Indexed: 02/07/2023]
Abstract
Autophagy serves a dichotomous role in cancer and recent advances have helped delineate the appropriate settings where inhibiting or promoting autophagy may confer therapeutic efficacy in patients. Our evolving understanding of the molecular machinery responsible for the tightly controlled regulation of this homeostatic mechanism has begun to bear fruit in the way of autophagy-oriented clinical trials and promising lead compounds to modulate autophagy for therapeutic benefit. In this manuscript we review the recent preclinical and clinical therapeutic strategies that involve autophagy modulation in cancer.
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Thévenod F, Lee WK. Live and Let Die: Roles of Autophagy in Cadmium Nephrotoxicity. TOXICS 2015; 3:130-151. [PMID: 29056654 PMCID: PMC5634690 DOI: 10.3390/toxics3020130] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 03/30/2015] [Accepted: 04/03/2015] [Indexed: 01/07/2023]
Abstract
The transition metal ion cadmium (Cd2+) is a significant environmental contaminant. With a biological half-life of ~20 years, Cd2+ accumulates in the kidney cortex, where it particularly damages proximal tubule (PT) cells and can result in renal fibrosis, failure, or cancer. Because death represents a powerful means by which cells avoid malignant transformation, it is crucial to clearly identify and understand the pathways that determine cell fate in chronic Cd2+ nephrotoxicity. When cells are subjected to stress, they make a decision to adapt and survive, or—depending on the magnitude and duration of stress—to die by several modes of death (programmed cell death), including autophagic cell death (ACD). Autophagy is part of a larger system of intracellular protein degradation and represents the channel by which organelles and long-lived proteins are delivered to the lysosome for degradation. Basal autophagy levels in all eukaryotic cells serve as a dynamic physiological recycling system, but they can also be induced by intra- or extracellular stress and pathological processes, such as endoplasmic reticulum (ER) stress. In a context-dependent manner, autophagy can either be protective and hence contribute to survival, or promote death by non-apoptotic or apoptotic pathways. So far, the role of autophagy in Cd2+-induced nephrotoxicity has remained unsettled due to contradictory results. In this review, we critically survey the current literature on autophagy in Cd2+-induced nephrotoxicity in light of our own ongoing studies. Data obtained in kidney cells illustrate a dual and complex function of autophagy in a stimulus- and time-dependent manner that possibly reflects distinct outcomes in vitro and in vivo. A better understanding of the context-specific regulation of cell fate by autophagy may ultimately contribute to the development of preventive and novel therapeutic strategies for acute and chronic Cd2+ nephrotoxicity.
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Affiliation(s)
- Frank Thévenod
- Institute of Physiology, Pathophysiology & Toxicology, Center for Biomedical Training and Research (ZBAF), Stockumer Str. 12, University of Witten/Herdecke, 58453 Witten, Germany.
| | - Wing-Kee Lee
- Institute of Physiology, Pathophysiology & Toxicology, Center for Biomedical Training and Research (ZBAF), Stockumer Str. 12, University of Witten/Herdecke, 58453 Witten, Germany.
- Laboratory of Signal Transduction, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10021, USA.
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