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Choo Z, Koh X, Wong MRE, Ashokan RM, Ali Ahamed NSB, Kang C, Kuick CH, Chang KTE, Larisch S, Loh AHP, Chen ZX. Targeted Degradation of XIAP is Sufficient and Specific to Induce Apoptosis in MYCN-overexpressing High-risk Neuroblastoma. CANCER RESEARCH COMMUNICATIONS 2023; 3:2386-2399. [PMID: 37874199 PMCID: PMC10681007 DOI: 10.1158/2767-9764.crc-23-0082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 07/22/2023] [Accepted: 10/16/2023] [Indexed: 10/25/2023]
Abstract
XIAP, the most potent mammalian inhibitor of apoptosis protein (IAP), critically restricts developmental culling of sympathetic neuronal progenitors, and is correspondingly overexpressed in most MYCN-amplified neuroblastoma tumors. Because apoptosis-related protein in the TGFβ signaling pathway (ARTS) is the only XIAP antagonist that directly binds and degrades XIAP, we evaluated the preclinical effectiveness and tolerability of XIAP antagonism as a novel targeting strategy for neuroblastoma. We found that antagonism of XIAP, but not other IAPs, triggered apoptotic death in neuroblastoma cells. XIAP silencing induced apoptosis while overexpression conferred protection from drug-induced apoptosis. From a screen of IAP inhibitors, first-in-class ARTS mimetic A4 was most effective against high-risk and high XIAP-expressing neuroblastoma cells, and least toxic toward normal liver- and bone marrow-derived cells, compared with pan-IAP antagonists. On target engagement assays and nuclear magnetic resonance spectroscopy, A4 was observed to degrade rather than inhibit XIAP, catalyzing rapid degradation of XIAP through the ubiquitin-proteasome pathway. In MYCN-amplified neuroblastoma patient-derived xenografts, A4 significantly prolonged survival as a single agent, and demonstrated synergism with standard-of-care agents to reduce their effective required doses 3- to 6-fold. Engagement and degradation of XIAP by ARTS mimetics is a novel targeting strategy for neuroblastoma that may be especially effective against MYCN-amplified disease with intrinsically high XIAP expression. First-in-class ARTS mimetic A4 demonstrates preclinical efficacy and warrants further development and study. SIGNIFICANCE XIAP degradation is sufficient to kill MYCN-amplified neuroblastoma which overexpresses and relies on XIAP as a brake against cell death, without affecting normal cells.
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Affiliation(s)
- Zhang'E Choo
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Xiaoying Koh
- Experimental Drug Development Centre, A*STAR, Singapore
| | - Megan Rui En Wong
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore
| | - Ruth Minothini Ashokan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Nurul Suhana Binte Ali Ahamed
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - CongBao Kang
- Experimental Drug Development Centre, A*STAR, Singapore
| | - Chik Hong Kuick
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore
| | - Kenneth Tou En Chang
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore
- Duke NUS Medical School, Singapore
| | - Sarit Larisch
- Cell Death and Cancer Research Laboratory, Department of Human Biology and Medical Sciences, University of Haifa, Haifa, Israel
| | - Amos Hong Pheng Loh
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore
- Duke NUS Medical School, Singapore
- Cell Death and Cancer Research Laboratory, Department of Human Biology and Medical Sciences, University of Haifa, Haifa, Israel
- Department of Paediatric Surgery, KK Women's and Children's Hospital, Singapore
| | - Zhi Xiong Chen
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore
- National University Cancer Institute, Singapore, National University Health System, Singapore
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Fleischmann J, Hildebrand LS, Kuhlmann L, Fietkau R, Distel LV. The Effect of Xevinapant Combined with Ionizing Radiation on HNSCC and Normal Tissue Cells and the Impact of Xevinapant on Its Targeted Proteins cIAP1 and XIAP. Cells 2023; 12:1653. [PMID: 37371123 DOI: 10.3390/cells12121653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 05/24/2023] [Accepted: 06/15/2023] [Indexed: 06/29/2023] Open
Abstract
The poor prognosis of HNSCC is partly due to treatment resistance. The SMAC mimetic Xevinapant is a promising new approach to targeted cancer therapy. Xevinapant inhibits cIAP1/2 and XIAP, leading to apoptosis, necroptosis and inhibition of prosurvival signaling. Combining Xevinapant with IR could improve therapeutic potential. The effect of Xevinapant in combination with IR on HNSCC and healthy tissue cells was investigated. Cell growth, cell death, clonogenic survival and DNA double-strand breaks (DSBs) were studied, and intracellular cIAP1 and XIAP levels were evaluated. Xevinapant had cytostatic and cytotoxic, as well as radiosensitizing, effects on the malignant cells, while healthy tissue cells were less affected. Apoptotic and necrotic cell death was particularly affected, but the increase in residual DSBs and the reduced survival implied an additional effect of Xevinapant on DNA damage repair and other cell inactivation mechanisms. cIAP1 and XIAP levels varied for each cell line and were affected by Xevinapant and IR treatment. There was an association between higher IAP levels and increased cell death. Xevinapant appears to be a potent new drug for HNSCC therapy, especially in combination with IR. IAP levels could be an indicator for impaired DNA damage repair and increased susceptibility to cellular stress.
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Affiliation(s)
- Julia Fleischmann
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Laura S Hildebrand
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Lukas Kuhlmann
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Rainer Fietkau
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Luitpold V Distel
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
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Hunkeler M, Jin CY, Fischer ES. Structures of BIRC6-client complexes provide a mechanism of SMAC-mediated release of caspases. Science 2023; 379:1105-1111. [PMID: 36758104 DOI: 10.1126/science.ade5750] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Tight regulation of apoptosis is essential for metazoan development and prevents diseases such as cancer and neurodegeneration. Caspase activation is central to apoptosis, and inhibitor of apoptosis proteins (IAPs) are the principal actors that restrain caspase activity and are therefore attractive therapeutic targets. IAPs, in turn, are regulated by mitochondria-derived proapoptotic factors such as SMAC and HTRA2. Through a series of cryo-electron microscopy structures of full-length human baculoviral IAP repeat-containing protein 6 (BIRC6) bound to SMAC, caspases, and HTRA2, we provide a molecular understanding for BIRC6-mediated caspase inhibition and its release by SMAC. The architecture of BIRC6, together with near-irreversible binding of SMAC, elucidates how the IAP inhibitor SMAC can effectively control a processive ubiquitin ligase to respond to apoptotic stimuli.
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Affiliation(s)
- Moritz Hunkeler
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Cyrus Y Jin
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Eric S Fischer
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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4
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Tavakoli S, Firoozpour L, Davoodi J. The synergistic effect of chimeras consisting of N-terminal smac and modified KLA peptides in inducing apoptosis in breast cancer cell lines. Biochem Biophys Res Commun 2023; 655:138-144. [PMID: 36934589 DOI: 10.1016/j.bbrc.2023.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 02/26/2023] [Accepted: 03/05/2023] [Indexed: 03/08/2023]
Abstract
Drug resistance is one of the most important obstacles in effective cancer therapy triggered through various mechanisms. One of these mechanisms is caused by the upregulation of Inhibitor of Apoptosis Proteins (IAPs). IAPs, inhibit apoptosis through direct and/or indirect caspase inhibition, which themselves are antagonized by an endogenous protein called Second Mitochondrial-derived Activator of Caspases, Smac/Diablo, mediated by the presence of a tetrapeptide IAP binding motif at its N-terminus. Accordingly, Smac-based peptides are under intense investigation as anti-cancer drugs and have reached Phase 2 clinical trials, although, Smac based peptides or mimetics alone have not been effective as anti-cancer agents. On the other hand, KLA peptide has shown major toxicity against cancer cells through the induction of apoptosis. Consequently, we designed an anti-cancer chimera by fusing an octa-peptide from the N-terminus of mature Smac protein to a modified proapoptotic KLA peptide (KLAKLCKKLAKLCK) to be called Smac-KLA. This chimera, therefore, possesses both proapoptotic and anti-IAP activities. In addition, we dimerized this chimera via intermolecular disulfide bonds in order to enhance their cellular permeability. Both the Smac-KLA monomeric and dimeric peptides exhibited cytotoxic activity against both MCF-7 and MDA-MB231 breast cancer cell lines at low micromolar concentrations. Importantly, the dimerization of the chimeras enhanced their potency 2-4- fold due to higher cellular uptake.
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Affiliation(s)
- Somayeh Tavakoli
- Institute of Biochemistry and Biophysics, University of Tehran, Postal code: 1417614335, Tehran, Iran
| | - Loghman Firoozpour
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Jamshid Davoodi
- Institute of Biochemistry and Biophysics, University of Tehran, Postal code: 1417614335, Tehran, Iran.
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5
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Campbell GR, Spector SA. Current strategies to induce selective killing of HIV-1-infected cells. J Leukoc Biol 2022; 112:1273-1284. [PMID: 35707952 PMCID: PMC9613504 DOI: 10.1002/jlb.4mr0422-636r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 04/24/2022] [Indexed: 01/02/2023] Open
Abstract
Although combination antiretroviral therapy (ART) has led to significant HIV-1 suppression and improvement in immune function, persistent viral reservoirs remain that are refractory to intensified ART. ART poses many challenges such as adherence to drug regimens, the emergence of resistant virus, and cumulative toxicity resulting from long-term therapy. Moreover, latent HIV-1 reservoir cells can be stochastically activated to produce viral particles despite effective ART and contribute to the rapid viral rebound that typically occurs within 2 weeks of ART interruption; thus, lifelong ART is required for continued viral suppression. Several strategies have been proposed to address the HIV-1 reservoir such as reactivation of HIV-1 transcription using latency reactivating agents with a combination of ART, host immune clearance and HIV-1-cytotoxicity to purge the infected cells-a "shock and kill" strategy. However, these approaches do not take into account the multiple transcriptional and translational blocks that contribute to HIV-1 latency or the complex heterogeneity of the HIV-1 reservoir, and clinical trials have thus far failed to produce the desired results. Here, we describe alternative strategies being pursued that are designed to kill selectively HIV-1-infected cells while sparing uninfected cells in the absence of enhanced humoral or adaptive immune responses.
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Affiliation(s)
- Grant R. Campbell
- Department of PediatricsDivision of Infectious DiseasesUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Stephen A. Spector
- Department of PediatricsDivision of Infectious DiseasesUniversity of California San DiegoLa JollaCaliforniaUSA,Division of Infectious DiseasesRady Children's HospitalSan DiegoCaliforniaUSA
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6
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Cellular Concentration of Survivin and Caspase 3 in Habitual Tobacco Chewers with and without Oral Squamous Cell Carcinoma in South Indian Rural Population-A Case Control Study. Diagnostics (Basel) 2022; 12:diagnostics12092249. [PMID: 36140650 PMCID: PMC9497477 DOI: 10.3390/diagnostics12092249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/02/2022] [Accepted: 09/05/2022] [Indexed: 12/02/2022] Open
Abstract
Background: There is paucity of data on tissue levels of Survivin and Caspase 3 in south Indian tobacco chewers with oral Squamous cell carcinoma (OSCC). Oral cancer is a rapidly growing, highly prevalent head and neck malignancy; it involves a mucosal epithelium of a buccal cavity exposed to tobacco and other carcinogens. The basis of the survival of a tumor cell or transformed normal cell into a neoplastic cell is by the suppression of apoptosis regulation. Recently, researchers have focused on Survivin, an inhibitor of apoptosis family of proteins (IAP), involved in apoptosis regulation in cancer cells targeting the executioner Caspase 3. The current study aims to quantify the cellular levels of Survivin and Caspase 3 in tobacco chewers with OSCC and in habitual tobacco chewers without OSCC, in comparison to controls. Methods: A single centric case control study included 186 study subjects, categorized into: Group I (n = 63), habitual tobacco chewers with OSCC; Group 2 (n = 63), habitual tobacco chewers without OSCC; and Group 3 (n = 63), the controls. Resected tumor tissue from Group 1 and buccal cell samples from Groups 2 and 3 were collected into phosphate buffer saline (PBS) and assayed for Survivin and Caspase 3 levels by the ELISA sandwich method. Results: The mean ± SD of the Survivin protein in Group 1 was (1670.9 ± 796.21 pg/mL); in Group 2, it was (1096.02 ± 346.17 pg/mL); and in Group 3, it was (397.5 ± 96.1 pg/mL) with a significance of p < 0.001. Similarly, the level of Caspase 3 in Group 1 was (7.48 ± 2.67 ng/mL); in Group 2, it was (8.85 ± 2.41 ng/mL); and in Group 3, it was (2.27 ± 2.24 ng/mL) with a significance of p < 0.001. Conclusion: The progressive transformation of buccal cells to neoplastic cells is evident; in the case of OSCC, this indicates that the over-expression of Survivin compared to Caspase 3 confirms the suppression and dysregulation of apoptosis.
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7
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Flierl A, Schriner SE, Hancock S, Coskun PE, Wallace DC. The mitochondrial adenine nucleotide transporters in myogenesis. Free Radic Biol Med 2022; 188:312-327. [PMID: 35714845 DOI: 10.1016/j.freeradbiomed.2022.05.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 05/21/2022] [Accepted: 05/25/2022] [Indexed: 01/06/2023]
Abstract
Adenine Nucleotide Translocator isoforms (ANTs) exchange ADP/ATP across the inner mitochondrial membrane, are also voltage-activated proton channels and regulate mitophagy and apoptosis. The ANT1 isoform predominates in heart and muscle while ANT2 is systemic. Here, we report the creation of Ant mutant mouse myoblast cell lines with normal Ant1 and Ant2 genes, deficient in either Ant1 or Ant2, and deficient in both the Ant1 and Ant2 genes. These cell lines are immortal under permissive conditions (IFN-γ + serum at 32 °C) permitting expansion but return to normal myoblasts that can be differentiated into myotubes at 37 °C. With this system we were able to complement our Ant1 mutant studies by demonstrating that ANT2 is important for myoblast to myotube differentiation and myotube mitochondrial respiration. ANT2 is also important in the regulation of mitochondrial biogenesis and antioxidant defenses. ANT2 is also associated with increased oxidative stress response and modulation for Ca++ sequestration and activation of the mitochondrial permeability transition (mtPTP) pore during cell differentiation.
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Affiliation(s)
- Adrian Flierl
- Center for Molecular and Mitochondrial Medicine and Genetics and the Department of Biological Chemistry, University of California, Irvine, CA, USA
| | - Samuel E Schriner
- Center for Molecular and Mitochondrial Medicine and Genetics and the Department of Biological Chemistry, University of California, Irvine, CA, USA
| | - Saege Hancock
- Center for Molecular and Mitochondrial Medicine and Genetics and the Department of Biological Chemistry, University of California, Irvine, CA, USA; Center for Mitochondrial and Epigenomic Medicine, Department of Pediatrics, Division of Human Genetics, Children's Hospital of Philadelphia and The Perelman School of Medicine, University of Pennsylvania, PA, USA
| | - Pinar E Coskun
- Center for Molecular and Mitochondrial Medicine and Genetics and the Department of Biological Chemistry, University of California, Irvine, CA, USA
| | - Douglas C Wallace
- Center for Molecular and Mitochondrial Medicine and Genetics and the Department of Biological Chemistry, University of California, Irvine, CA, USA; Center for Mitochondrial and Epigenomic Medicine, Department of Pediatrics, Division of Human Genetics, Children's Hospital of Philadelphia and The Perelman School of Medicine, University of Pennsylvania, PA, USA.
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Tsai YT, Huang HC, Kao ST, Chang TT, Cheng CY. Neuroprotective Effects of Alpinia oxyphylla Miq against Mitochondria-Related Apoptosis by the Interactions between Upregulated p38 MAPK Signaling and Downregulated JNK Signaling in the Subacute Phase of Cerebral Ischemia-Reperfusion in Rats. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2022; 50:2057-2083. [DOI: 10.1142/s0192415x22500884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Apoptosis in the penumbra region is the major cell death mechanism occurring during ischemia–reperfusion injury’s early phase. Here, we evaluated how the Alpinia oxyphylla Miq (AOM) affects mitochondria-related apoptosis 3 days after transient middle cerebral artery occlusion (MCAo) and examined the mechanisms underlying the regulation of MAPK-mediated mitochondria-related apoptotic signaling in the peri-infarct cortex in rats. The rats were administered the AOM extract intraperitoneally at doses of 0.2[Formula: see text]g/kg (AOM-0.2[Formula: see text]g), 0.4[Formula: see text]g/kg (AOM-0.4[Formula: see text]g), or 0.8[Formula: see text]g/kg (AOM-0.8[Formula: see text]g) at MCAo initiation. The AOM-0.4[Formula: see text]g and AOM-0.8[Formula: see text]g significantly ameliorated apoptotic cell death and considerably downregulated cytochrome c (cyto c) and cleaved caspase-3 immunoreactivity 3 days after reperfusion. Simultaneously, they significantly downregulated cytosolic p-JNK/JNK, cathepsin B/actin, cyto c/actin, Smac/DIABLO/actin, cleaved caspase-3/actin, and AIF/actin and mitochondrial p53/HSP60 and Bax/HSP60 fractions but upregulated cytosolic p-p38 MAPK/p38 MAPK, p-p90RSK/actin, p-Bad/Bad, p-CREB/actin, and XIAP/actin and cytosolic and mitochondrial Bcl-2/Bax and Bcl-xL/Bax fractions in the peri-infarct cortex. Pretreatment with SB203580 — a p38 MAPK inhibitor — completely abrogated the effects of AOM-0.8[Formula: see text]g on the aforementioned protein expression, whereas treatment with SP600125 — a JNK inhibitor — exerted protective effects similar to those of AOM-0.8[Formula: see text]g. Treatment with 0.4 or 0.8[Formula: see text]g/kg AOM has neuroprotective effects against mitochondria-related apoptosis by suppressing cyto c, Smac/DIABLO, and AIF release from the mitochondria to cytosol. The anti-mitochondria related apoptotic effects of the AOM extract are attributable to the interactions between upregulated p38 MAPK/p90RSK-mediated p-Bad and CREB signaling and downregulated JNK/cathepsin B-mediated Bax and p53 signaling in the peri-infarct cortex 3 days after transient MCAo.
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Affiliation(s)
- Yueh-Ting Tsai
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University Taichung 40402, Taiwan
- Department of Traditional Chinese Medicine, Kuang Tien General Hospital, Taichung, Taiwan
| | - Hui-Chi Huang
- Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Chinese Medicine, China Medical University Taichung 40402, Taiwan
| | - Shung-Te Kao
- School of Chinese Medicine, College of Chinese Medicine, China Medical University Taichung 40402, Taiwan
| | - Tung-Ti Chang
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University Taichung 40402, Taiwan
| | - Chin-Yi Cheng
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University Taichung 40402, Taiwan
- Department of Chinese Medicine, Hui-Sheng Hospital, Taichung 42056, Taiwan
- Department of Chinese Medicine, China Medical University Hospital, Taichung 42056, Taiwan
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Chang Z, Dang T, Meng X, Chai J. The Role of CCN1 in Esophageal Adenocarcinoma: What We Have Learned From the Lab. Cancer Control 2022; 29:10732748221074734. [PMID: 35291889 PMCID: PMC8935545 DOI: 10.1177/10732748221074734] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background: Esophageal cancer is one of the most common and deadliest cancers in the world, particularly esophageal adenocarcinoma. There has never been a special drug to treat it.Purpose: This article summarizes the work that we have done in our laboratory about the role of CCN1 in esophageal cancer and gives a new perspective of CCN1 biology.Research Design: This is a review article. Study Sample: The work was done using validated cell lines and fixed human tissue slides.Data Collection and Analysis: This is a review article, therefore, no data collection or analysis was involved.Results: CCN1 is a matricellular protein supporting adhesion, migration, and survival in normal cells, but in the esophageal cancer cells, it induces TRAIL-mediated apoptosis. CCN1 promotes TRAIL and its death receptor expression but downregulates the decoy receptors and survivin in a p53-dependant manner. It was thought that CCN1 relies on TNF to induce apoptosis, but our study found that these two molecules antagonize each other. CCN1 promotes TNFR1 cleavage and uses the soluble product to block TNF signaling, while TNF upregulates PGLYRP1 to overcome this obstacle because PGLYRP1 is a secreted protein that competes with TNF for TNFR1 binding. As a result, when CCN1 and TNF are present together in the vicinity of esophageal tumors, they cancel each other out.Conclusions: Based on our laboratory study, CCN1 has much potential to be a candidate for the treatment of esophageal cancer.
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Affiliation(s)
- Zhiheng Chang
- Inner Mongolia Institute of Digestive Diseases, Inner Mongolia Engineering Research Center for Prevention and Treatment of Digestive Diseases, Inner Mongolia University of Science and Technology, 74506The Second Affiliated Hospital of Baotou Medical College, Baotou, China
| | - Tong Dang
- Inner Mongolia Institute of Digestive Diseases, Inner Mongolia Engineering Research Center for Prevention and Treatment of Digestive Diseases, Inner Mongolia University of Science and Technology, 74506The Second Affiliated Hospital of Baotou Medical College, Baotou, China
| | - Xianmei Meng
- Inner Mongolia Institute of Digestive Diseases, Inner Mongolia Engineering Research Center for Prevention and Treatment of Digestive Diseases, Inner Mongolia University of Science and Technology, 74506The Second Affiliated Hospital of Baotou Medical College, Baotou, China
| | - Jianyuan Chai
- Inner Mongolia Institute of Digestive Diseases, Inner Mongolia Engineering Research Center for Prevention and Treatment of Digestive Diseases, Inner Mongolia University of Science and Technology, 74506The Second Affiliated Hospital of Baotou Medical College, Baotou, China.,Laboratory of Gastrointestinal Injury and Cancer, VA Long Beach Healthcare System, Long Beach, CA, USA.,College of Medicine, University of California, Irvine, CA, USA
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10
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Campbell GR, Zhuang J, Zhang G, Landa I, Kubiatowicz LJ, Dehaini D, Fang RH, Zhang L, Spector SA. CD4+ T cell-mimicking nanoparticles encapsulating DIABLO/SMAC mimetics broadly neutralize HIV-1 and selectively kill HIV-1-infected cells. Theranostics 2021; 11:9009-9021. [PMID: 34522224 PMCID: PMC8419049 DOI: 10.7150/thno.59728] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 07/22/2021] [Indexed: 12/16/2022] Open
Abstract
HIV-1 is a major global health challenge. The development of an effective vaccine and a therapeutic cure are top priorities. The creation of vaccines that focus an antibody response toward a particular epitope of a protein has shown promise, but the genetic diversity of HIV-1 stymies this progress. Therapeutic strategies that provide effective and broad‐spectrum neutralization against HIV-1 infection are highly desirable. Methods: We investigated the potential of nanoengineered CD4+ T cell membrane-coated nanoparticles (TNP) encapsulating the DIABLO/SMAC mimetics LCL-161 or AT-406 (also known as SM-406 or Debio 1143) to both neutralize HIV-1 and selectively kill HIV-1-infected resting CD4+ T cells and macrophages. Results: DIABLO/SMAC mimetic-loaded TNP displayed outstanding neutralizing breadth and potency, and selectively kill HIV-1-infected cells via autophagy-dependent apoptosis while having no drug-induced off-target or cytotoxic effects on bystander cells. Genetic inhibition of early stages of autophagy abolishes this effect. Conclusion: DIABLO/SMAC mimetic loaded TNP have the potential to be used as therapeutic agents to neutralize cell-free HIV-1 and to kill specifically HIV-1-infected cells as part of an HIV-1 cure strategy.
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Wynen H, Heyland A. Hormonal Regulation of Programmed Cell Death in Sea Urchin Metamorphosis. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.733787] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Programmed cell death (PCD) has been identified as a key process in the metamorphic transition of indirectly developing organisms such as frogs and insects. Many marine invertebrate species with indirect development and biphasic life cycles face the challenge of completing the metamorphic transition of the larval body into a juvenile when they settle into the benthic habitat. Some key characteristics stand out during this transition in comparison to frogs and insects: (1) the transition is often remarkably fast and (2) the larval body is largely abandoned and few structures transition into the juvenile stage. In sea urchins, a group with a drastic and fast metamorphosis, development and destruction of the larval body is regulated by endocrine signals. Here we provide a brief review of the basic regulatory mechanisms of PCD in animals. We then narrow our discussion to metamorphosis with a specific emphasis on sea urchins with indirect life histories and discuss the function of thyroid hormones and histamine in larval development, metamorphosis and settlement of the sea urchin Strongylocentrotus purpuratus. We were able to annotate the large majority of PCD related genes in the sea urchin S. purpuratus and ongoing studies on sea urchin metamorphosis will shed light on the regulatory architecture underlying this dramatic life history transition. While we find overwhelming evidence for hormonal regulation of PCD in animals, especially in the context of metamorphosis, the mechanisms in many marine invertebrate groups with indirect life histories requires more work. Hence, we propose that studies of PCD in animals requires functional studies in whole organisms rather than isolated cells. We predict that future work, targeting a broader array of organisms will not only help to reveal important new functions of PCD but provide a fundamentally new perspective on its use in a diversity of taxonomic, developmental, and ecological contexts.
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12
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Campbell GR, Spector SA. Induction of Autophagy to Achieve a Human Immunodeficiency Virus Type 1 Cure. Cells 2021; 10:cells10071798. [PMID: 34359967 PMCID: PMC8307643 DOI: 10.3390/cells10071798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/13/2021] [Accepted: 07/13/2021] [Indexed: 02/06/2023] Open
Abstract
Effective antiretroviral therapy has led to significant human immunodeficiency virus type 1 (HIV-1) suppression and improvement in immune function. However, the persistence of integrated proviral DNA in latently infected reservoir cells, which drive viral rebound post-interruption of antiretroviral therapy, remains the major roadblock to a cure. Therefore, the targeted elimination or permanent silencing of this latently infected reservoir is a major focus of HIV-1 research. The most studied approach in the development of a cure is the activation of HIV-1 expression to expose latently infected cells for immune clearance while inducing HIV-1 cytotoxicity—the “kick and kill” approach. However, the complex and highly heterogeneous nature of the latent reservoir, combined with the failure of clinical trials to reduce the reservoir size casts doubt on the feasibility of this approach. This concern that total elimination of HIV-1 from the body may not be possible has led to increased emphasis on a “functional cure” where the virus remains but is unable to reactivate which presents the challenge of permanently silencing transcription of HIV-1 for prolonged drug-free remission—a “block and lock” approach. In this review, we discuss the interaction of HIV-1 and autophagy, and the exploitation of autophagy to kill selectively HIV-1 latently infected cells as part of a cure strategy. The cure strategy proposed has the advantage of significantly decreasing the size of the HIV-1 reservoir that can contribute to a functional cure and when optimised has the potential to eradicate completely HIV-1.
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Affiliation(s)
- Grant R. Campbell
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA;
- Correspondence: ; Tel.: +1-858-534-7477
| | - Stephen A. Spector
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA;
- Rady Children’s Hospital, San Diego, CA 92123, USA
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13
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Ahmad I, Dera A, Irfan S, Rajagopalan P, Ali Beg M, Alshahrani M, Mir M, Abohashrh M, Alam M, Wahab S, Verma A, Srivastava S. BV6 enhances apoptosis in Lung cancer cells by ameliorating caspase expressions through attenuation of XIAP, cIAP-1, and cIAP-2 proteins. J Cancer Res Ther 2021; 18:1651-1657. [PMID: 36412426 DOI: 10.4103/jcrt.jcrt_1281_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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14
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Hayes AML. Future approaches to clearing the latent human immunodeficiency virus reservoir: Beyond latency reversal. South Afr J HIV Med 2020; 21:1089. [PMID: 32934831 PMCID: PMC7479387 DOI: 10.4102/sajhivmed.v21i1.1089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 05/12/2020] [Indexed: 11/01/2022] Open
Abstract
Background While combined antiretroviral therapy (cART) allows near-normal life expectancy for people living with human immunodeficiency virus (HIV), it is unable to cure the infection and so life long treatment is required. Objectives The main barrier to curing HIV is the latent reservoir of cells, which is stable and resistant to cART. Method Current approaches under investigation for clearing this reservoir propose a 'Shock and Kill' mechanism, in which active replication is induced in latent cells by latency reversal agents, theoretically allowing killing of the newly active cells. Results However, previous studies have failed to achieve depletion of the T central memory cell reservoir, are unable to target other latent reservoirs and may be causing neurological damage to participants. Conclusion Future approaches to clearing the latent reservoir may bypass latency reversal through the use of drugs that selectively induce apoptosis in infected cells. Several classes of these pro-apoptotic drugs have shown promise in in vitro and ex vivo studies, and may represent the basis of a future functional cure for HIV.
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Affiliation(s)
- Alexander M L Hayes
- Medical Sciences Division, Faculty of Clinical Medicine, University of Oxford, Oxford, United Kingdom
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15
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Campbell GR, To RK, Zhang G, Spector SA. SMAC mimetics induce autophagy-dependent apoptosis of HIV-1-infected macrophages. Cell Death Dis 2020; 11:590. [PMID: 32719312 PMCID: PMC7385130 DOI: 10.1038/s41419-020-02761-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 06/29/2020] [Accepted: 07/06/2020] [Indexed: 12/18/2022]
Abstract
Human immunodeficiency type 1 (HIV)-infected macrophages (HIV-Mφ) are a reservoir for latent HIV infection and a barrier to HIV eradication. In contrast to CD4+ T cells, HIV-Mφ are resistant to the cytopathic effects of acute HIV infection and have increased expression of cell survival factors, including X-linked inhibitor of apoptosis (XIAP), baculoviral IAP repeat containing (BIRC) 2/cIAP1, beclin-1, BCL2, BCL-xl, triggering receptor expressed on myeloid cells 1, mitofusin (MFN) 1, and MFN2. DIABLO/SMAC mimetics are therapeutic agents that affect cancer cell survival and induce cell death. We found that DIABLO/SMAC mimetics (LCL-161, AT-406 (also known as SM-406 or Debio 1143), and birinapant) selectively kill HIV-Mφ without increasing bystander cell death. DIABLO/SMAC mimetic treatment of HIV-Mφ-induced XIAP and BIRC2 degradation, leading to the induction of autophagy and the formation of a death-inducing signaling complex on phagophore membranes that includes both pro-apoptotic or necroptotic (FADD, receptor-interacting protein kinase (RIPK) 1, RIPK3, caspase 8, and MLKL) and autophagy (ATG5, ATG7, and SQSTM1) proteins. Genetic or pharmacologic inhibition of early stages of autophagy, but not late stages of autophagy, ablated this interaction and inhibited apoptosis. Furthermore, DIABLO/SMAC mimetic-mediated apoptosis of HIV-Mφ is dependent upon tumor necrosis factor signaling. Our findings thus demonstrate that DIABLO/SMAC mimetics selectively induce autophagy-dependent apoptosis in HIV-Mφ.
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Affiliation(s)
- Grant R Campbell
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA, USA.
| | - Rachel K To
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Gang Zhang
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
- Gladstone Center for HIV Cure Research, Gladstone Institute of Virology and Immunology, San Francisco, CA, USA
| | - Stephen A Spector
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA, USA.
- Rady Children's Hospital, San Diego, CA, USA.
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16
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Vaidya A, Jain S, Sahu S, Jain PK, Pathak K, Pathak D, Kumar R, Jain SK. Anticancer Agents Based on Vulnerable Components in a Signalling Pathway. Mini Rev Med Chem 2020; 20:886-907. [DOI: 10.2174/1389557520666200212105417] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 12/05/2019] [Accepted: 01/30/2020] [Indexed: 02/07/2023]
Abstract
Traditional cancer treatment includes surgery, chemotherapy, radiotherapy and immunotherapy
that are clinically beneficial, but are associated with drawbacks such as drug resistance and side
effects. In quest for better treatment, many new molecular targets have been introduced in the last few
decades. Finding new molecular mechanisms encourages researchers to discover new anticancer agents.
Exploring the mechanism of action also facilitates anticipation of potential resistance mechanisms and
optimization of rational combination therapies. The write up describes the leading molecular mechanisms
for cancer therapy, including mTOR, tyrosine Wee1 kinase (WEE1), Janus kinases, PI3K/mTOR
signaling pathway, serine/threonine protein kinase AKT, checkpoint kinase 1 (Chk1), maternal embryonic
leucine-zipper kinase (MELK), DNA methyltransferase I (DNMT1), poly (ADP-ribose) polymerase
(PARP)-1/-2, sphingosine kinase-2 (SK2), pan-FGFR, inhibitor of apoptosis (IAP), murine double minute
2 (MDM2), Bcl-2 family protein and reactive oxygen species 1 (ROS1). Additionally, the manuscript
reviews the anticancer drugs currently under clinical trials.
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Affiliation(s)
- Ankur Vaidya
- Pharmacy College Saifai, Uttar Pradesh University of Medical Sciences, Saifai, Etawah (U.P.), India
| | - Shweta Jain
- Sir MadanLal Institute of Pharmacy, Etawah (U.P.), India
| | - Sanjeev Sahu
- Department of Pharmaceutical Sciences, Lovely Professional University, Jalandhar, India
| | - Pankaj Kumar Jain
- Community Medicine, Uttar Pradesh University of Medical Sciences, Saifai, Etawah (U.P.), India
| | - Kamla Pathak
- Pharmacy College Saifai, Uttar Pradesh University of Medical Sciences, Saifai, Etawah (U.P.), India
| | - Devender Pathak
- Pharmacy College Saifai, Uttar Pradesh University of Medical Sciences, Saifai, Etawah (U.P.), India
| | - Raj Kumar
- Department of Neurosurgery, Uttar Pradesh University of Medical Sciences, Saifai, Etawah (U.P.), India
| | - Sanjay Kumar Jain
- Department of Pharmaceutical Sciences, Dr. Hari Singh Gour Vishwavidyalaya, Sagar, Madhya Pradesh, India
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Dietz A, Dalda N, Zielke S, Dittmann J, van Wijk SJL, Vogler M, Fulda S. Proteasome inhibitors and Smac mimetics cooperate to induce cell death in diffuse large B-cell lymphoma by stabilizing NOXA and triggering mitochondrial apoptosis. Int J Cancer 2020; 147:1485-1498. [PMID: 32170726 DOI: 10.1002/ijc.32976] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 03/03/2020] [Accepted: 03/10/2020] [Indexed: 12/12/2022]
Abstract
Copy number gains and increased expression levels of cellular Inhibitor of Apoptosis protein (cIAP)1 and cIAP2 have been identified in primary diffuse large B-cell lymphoma (DLBCL) tissues. Second mitochondria-derived activator of caspases (Smac) mimetics were designed to antagonize IAP proteins. However, since their effect as single agents is limited, combination treatment represents a strategy for their clinical development. Therefore, we investigated the Smac mimetic BV6 in combination with proteasome inhibitors and analyzed the molecular mechanisms of action. We discovered that BV6 treatment sensitizes DLBCL cells to proteasome inhibition. We show a synergistic decrease in cell viability and induction of apoptosis by BV6/Carfilzomib (CFZ) treatment, which was confirmed by calculation of combination index (CI) and Bliss score. BV6 and CFZ acted together to trigger activation of BAX and BAK, which facilitated cell death, as knockdown of BAX and BAK significantly reduced BV6/CFZ-mediated cell death. Activation of BAX and BAK was accompanied by loss of mitochondrial membrane potential (MMP) and activation of caspases. Pretreatment with the caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (zVAD.fmk) rescued BV6/CFZ-induced cell death, confirming caspase dependency. Treatment with CFZ alone or in combination with BV6 caused accumulation of NOXA, which was required for cell death, as gene silencing by siRNA or Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9-mediated NOXA inactivation inhibited BV6/CFZ-induced cell death. Together, these experiments indicate that BV6 and CFZ cooperatively induce apoptotic cell death via the mitochondrial pathway. These findings emphasize the role of Smac mimetics for sensitizing DLBCL cells to proteasome inhibition with important implications for further (pre)clinical studies.
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Affiliation(s)
- Anna Dietz
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Frankfurt, Frankfurt, Germany
| | - Nahide Dalda
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Frankfurt, Frankfurt, Germany
| | - Svenja Zielke
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Frankfurt, Frankfurt, Germany
| | - Jessica Dittmann
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Frankfurt, Frankfurt, Germany
| | - Sjoerd J L van Wijk
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Frankfurt, Frankfurt, Germany
| | - Meike Vogler
- Institute for Experimental Cancer Research in Pediatrics, Goethe University Frankfurt, Frankfurt, Germany
| | - 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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18
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Blaquiere N, Villemure E, Staben ST. Medicinal Chemistry of Inhibiting RING-Type E3 Ubiquitin Ligases. J Med Chem 2020; 63:7957-7985. [PMID: 32142281 DOI: 10.1021/acs.jmedchem.9b01451] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The ubiquitin proteasome system (UPS) presents many opportunities for pharmacological intervention. Key players in the UPS are E3 ubiquitin ligases, responsible for conjugation of ubiquitin to specific cognate substrates. Numbering more than 600 members, these ligases represent the most selective way to intervene within this physiologically important system. This Perspective highlights some of the dedicated medicinal chemistry efforts directed at inhibiting the function of specific single-protein and multicomponent RING-type E3 ubiquitin ligases. We present opportunities and challenges associated with targeting this important class of enzymes.
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Affiliation(s)
- Nicole Blaquiere
- Discovery Chemistry, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Elisia Villemure
- Discovery Chemistry, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Steven T Staben
- Discovery Chemistry, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
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19
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Abbas R, Larisch S. Targeting XIAP for Promoting Cancer Cell Death-The Story of ARTS and SMAC. Cells 2020; 9:E663. [PMID: 32182843 PMCID: PMC7140716 DOI: 10.3390/cells9030663] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/04/2020] [Accepted: 03/06/2020] [Indexed: 12/18/2022] Open
Abstract
Inhibitors of apoptosis (IAPs) are a family of proteins that regulate cell death and inflammation. XIAP (X-linked IAP) is the only family member that suppresses apoptosis by directly binding to and inhibiting caspases. On the other hand, cIAPs suppress the activation of the extrinsic apoptotic pathway by preventing the formation of pro-apoptotic signaling complexes. IAPs are negatively regulated by IAP-antagonist proteins such as Smac/Diablo and ARTS. ARTS can promote apoptosis by binding and degrading XIAP via the ubiquitin proteasome-system (UPS). Smac can induce the degradation of cIAPs but not XIAP. Many types of cancer overexpress IAPs, thus enabling tumor cells to evade apoptosis. Therefore, IAPs, and in particular XIAP, have become attractive targets for cancer therapy. In this review, we describe the differences in the mechanisms of action between Smac and ARTS, and we summarize efforts to develop cancer therapies based on mimicking Smac and ARTS. Several Smac-mimetic small molecules are currently under evaluation in clinical trials. Initial efforts to develop ARTS-mimetics resulted in a novel class of compounds, which bind and degrade XIAP but not cIAPs. Smac-mimetics can target tumors with high levels of cIAPs, whereas ARTS-mimetics are expected to be effective for cancers with high levels of XIAP.
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Affiliation(s)
| | - Sarit Larisch
- Laboratory of Cell Death and Cancer Research, Biology& Human Biology Departments, Faculty of Natural Sciences, University of Haifa, Haifa 3498838, Israel;
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20
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Jensen S, Seidelin JB, LaCasse EC, Nielsen OH. SMAC mimetics and RIPK inhibitors as therapeutics for chronic inflammatory diseases. Sci Signal 2020; 13:13/619/eaax8295. [PMID: 32071170 DOI: 10.1126/scisignal.aax8295] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
New therapeutic approaches for chronic inflammatory diseases such as inflammatory bowel disease, rheumatoid arthritis, and psoriasis are needed because current treatments are often suboptimal in terms of both efficacy and the risks of serious adverse events. Inhibitor of apoptosis proteins (IAPs) are E3 ubiquitin ligases that inhibit cell death pathways and are themselves inhibited by second mitochondria-derived activator of caspases (SMAC). SMAC mimetics (SMs), small-molecule antagonists of IAPs, are being evaluated as cancer therapies in clinical trials. IAPs are also crucial regulators of inflammatory pathways because they influence both the activation of inflammatory genes and the induction of cell death through the receptor-interacting serine-threonine protein kinases (RIPKs), nuclear factor κB (NF-κB)-inducing kinase, and mitogen-activated protein kinases (MAPKs). Furthermore, there is an increasing interest in specifically targeting the substrates of IAP-mediated ubiquitylation, especially RIPK1, RIPK2, and RIPK3, as druggable nodes in inflammation control. Several studies have revealed an anti-inflammatory potential of RIPK inhibitors that either block inflammatory signaling or block the form of inflammatory cell death known as necroptosis. Expanding research on innate immune signaling through pattern recognition receptors that stimulate proinflammatory NF-κB and MAPK signaling may further contribute to uncovering the complex molecular roles used by IAPs and downstream RIPKs in inflammatory signaling. This may benefit and guide the development of SMs or selective RIPK inhibitors as anti-inflammatory therapeutics for various chronic inflammatory conditions.
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Affiliation(s)
- Simone Jensen
- Department of Gastroenterology, Medical Section, Herlev Hospital, University of Copenhagen, 1 Borgmester Ib Juuls Vej, DK-2730 Herlev, Denmark
| | - Jakob Benedict Seidelin
- Department of Gastroenterology, Medical Section, Herlev Hospital, University of Copenhagen, 1 Borgmester Ib Juuls Vej, DK-2730 Herlev, Denmark.
| | - Eric Charles LaCasse
- Apoptosis Research Centre, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario K1H 8L1, Canada
| | - Ole Haagen Nielsen
- Department of Gastroenterology, Medical Section, Herlev Hospital, University of Copenhagen, 1 Borgmester Ib Juuls Vej, DK-2730 Herlev, Denmark
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21
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Zhu H, Li Y, Liu Y, Han B. Bivalent SMAC Mimetics for Treating Cancer by Antagonizing Inhibitor of Apoptosis Proteins. ChemMedChem 2019; 14:1951-1962. [DOI: 10.1002/cmdc.201900410] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/10/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Hongping Zhu
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of PharmacyChengdu University of Traditional Chinese Medicine 1166 Liutai Avenue Chengdu 611137 China
- Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of AntibioticsChengdu University 168 Huaguan Road Chengdu 610052 China
| | - Yi Li
- Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of AntibioticsChengdu University 168 Huaguan Road Chengdu 610052 China
| | - Yue Liu
- Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of AntibioticsChengdu University 168 Huaguan Road Chengdu 610052 China
| | - Bo Han
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of PharmacyChengdu University of Traditional Chinese Medicine 1166 Liutai Avenue Chengdu 611137 China
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22
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Wang L, Guo X, Guo X, Zhang X, Ren J. Decitabine promotes apoptosis in mesenchymal stromal cells isolated from patients with myelodysplastic syndromes by inducing reactive oxygen species generation. Eur J Pharmacol 2019; 863:172676. [PMID: 31542488 DOI: 10.1016/j.ejphar.2019.172676] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 09/11/2019] [Accepted: 09/18/2019] [Indexed: 10/26/2022]
Abstract
Myelodysplastic syndromes (MDSs) are a group of clonal disorders of hematopoietic stem cells, resulting in ineffective hematopoiesis. Previous studies have reported that decitabine (DAC) plays an essential role in cell cycle arrest and cell death induction in multiple cell types. Nevertheless, the effect of decitabine on mesenchymal stromal cells derived from bone marrow of patients with MDSs is not completely clarified. Here, we explored the apoptotic and anti-proliferative effect of DAC on MSCs isolated from patients with MDSs. Treatment with DAC inhibited cell growth in a concentration- and time-dependent manner by inducing apoptosis. We found a positive relationship between cell death triggered by DAC in MSCs and the death receptor family members Fas and FasL mRNA and protein levels (***P < 0.00085), cleaved caspase (-3, -8, and -9) activity, and mitochondrial membrane potential reduction. Additionally, DAC-induced apoptosis was inhibited by Kp7-6, a FasL/Fas antagonist, indicating a crucial role of FasL/Fas, a cell death receptor, in mediating the apoptotic effect of DAC. DAC also induced reactive oxygen species (ROS) generation in MSCs derived from MDSs patients (*P = 0.038). Furthermore, N-acetyl-L-cysteine (NAC), a widely accepted ROS scavenger, efficiently reversed DAC-induced apoptosis by inhibiting ROS generation (***P < 0.00051) in mitochondria and restoring mitochondrial membrane potential. Furthermore, ROS production was found to be a consequence of caspase activation via caspases inhibition. Our data imply that DAC triggers ROS production in human MSCs, which serves as a crucial factor for mitochondrial membrane potential reduction, and DAC induces cell death prior to FasL/Fas stimulation.
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Affiliation(s)
- Lihua Wang
- Department of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
| | - Xiaonan Guo
- Department of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
| | - Xiaoling Guo
- Department of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
| | - Xiaolei Zhang
- Department of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
| | - Jinhai Ren
- Department of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
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23
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Kyuno D, Zhao K, Schnölzer M, Provaznik J, Hackert T, Zöller M. Claudin7-dependent exosome-promoted reprogramming of nonmetastasizing tumor cells. Int J Cancer 2019; 145:2182-2200. [PMID: 30945750 DOI: 10.1002/ijc.32312] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 03/10/2019] [Accepted: 03/27/2019] [Indexed: 12/17/2022]
Abstract
Claudin7 (cld7) is a cancer-initiating cell (CIC) marker in gastrointestinal tumors, a cld7-knockdown (kd) being accompanied by loss of tumor progression. Tumor exosomes (TEX) restoring CIC activities, we explored the contribution of cld7. This became particularly interesting, as tight junction (TJ)- and glycolipid-enriched membrane domain (GEM)-derived cld7 is recruited into distinct TEX. TEXs were derived from CIC or cld7kd cells of a rat pancreatic and a human colon cancer line. TEX derived from pancreatic cancer cld7kd cells rescued with palmitoylation site-deficient cld7 (cld7mP) allowed selectively evaluating the contribution of GEM-derived TEX, only palmitoylated cld7 being integrated into GEM. Cld7 CIC-TEX promoted tumor cell dissemination and metastatic growth without a major impact on proliferation, apoptosis resistance and epithelial-mesenchymal transition. Instead, migration, invasion and (lymph)angiogenesis were strongly supported, only migration being selectively fostered by GEM-derived cld7 TEX. CIC-TEX coculture of cld7kd cells uncovered significant changes in the cld7kd cell protein and miRNA profiles. However, changes did not correspond to the CIC-TEX profile, CIC-TEX rather initiating integrin, protease and RTK, particularly lymphangiogenic receptor activation. CIC-TEX preferentially rescuing cld7kd-associated defects in signal transduction was backed up by an RTK inhibitor neutralizing the impact of CIC-TEX on tumor progression. In conclusion, cld7 contributes to selective steps of the metastatic cascade. Defects of cld7kd and cld7mP cells in migration, invasion and (lymph)angiogenesis are effaced by CIC-TEX that act by signaling cascade activation. Accordingly, RTK inhibitors are an efficient therapeutic defeating CIC-TEX.
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Affiliation(s)
- Daisuke Kyuno
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany.,Department of Surgery, Surgical Oncology and Science, Sapporo Medical University, Sapporo, Japan
| | - Kun Zhao
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany
| | - Martina Schnölzer
- Functional Proteome Analysis, German Cancer Research Center, Heidelberg, Germany
| | | | - Thilo Hackert
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany
| | - Margot Zöller
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany
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24
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Huang Q, Peng Y, Peng Y, Wei D, Wei Y, Feng S. The TwistDock workflow for evaluation of bivalent Smac mimetics targeting XIAP. DRUG DESIGN DEVELOPMENT AND THERAPY 2019; 13:1373-1388. [PMID: 31118573 PMCID: PMC6499140 DOI: 10.2147/dddt.s194276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 02/05/2019] [Indexed: 01/13/2023]
Abstract
Purpose: Mimetics based on Smac, the native inhibitor of XIAP, are promising drug-candidates for the treatment of cancer. Bivalent Smac mimetics inhibit XIAP with even higher potency than monovalent mimetics, but how to optimize the linker that tethers the two monovalent binding motifs remains controversial. Methods: To construct an ensemble of bivalent complex structures for evaluating various linkers, we propose herein a workflow, named TwistDock, consisting of steps of monovalent docking and linker twisting, in which the degrees of freedom are sampled focusing on the rotation of single bonds of the linker. Results: The obtained conformations of bivalent complex distribute randomly in the conformational space with respect to two reaction coordinates introduced by the linker, which are the distance of the two binding motifs and the dihedral angle of the two planes through the linker and each of the binding motifs. Molecular dynamics starting from 10 conformations with the lowest enthalpy of every complex shows that the conformational tendency of the complex participated by compound 9, one of the compounds with the largest binding affinity, is distinct from others. By umbrella sampling of the complex, we find its global minimum of the free energy landscape. The structure shows that the linker favors a compact conformation, and the two BIR domains of XIAP encompass the ligand on the opposite sides. Conclusion: TwistDock can be used in fine-tuning of bivalent ligands targeting XIAP and similar receptors dimerized or oligomerized.
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Affiliation(s)
- Qingsheng Huang
- Joint Engineering Research Center for Health Big Data Intelligent Analysis Technology and Center for High Performance Computing, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, People's Republic of China
| | - Yin Peng
- Department of Pathology, Shenzhen University School of Medicine, Shenzhen, Guangdong, People's Republic of China
| | - Yuefeng Peng
- Joint Engineering Research Center for Health Big Data Intelligent Analysis Technology and Center for High Performance Computing, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, People's Republic of China.,Center for Drug Evaluation and Research (CDER), Food and Drug Administration (FDA), Silver Spring, MD 20903, USA
| | - Dan Wei
- School of Computer Science and Technology, Hangzhou Dianzi University, Hangzhou, People's Republic of China
| | - Yanjie Wei
- Joint Engineering Research Center for Health Big Data Intelligent Analysis Technology and Center for High Performance Computing, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, People's Republic of China
| | - Shengzhong Feng
- Joint Engineering Research Center for Health Big Data Intelligent Analysis Technology and Center for High Performance Computing, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, People's Republic of China
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25
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Dang T, Modak C, Meng X, Wu J, Narvaez R, Chai J. CCN1 induces apoptosis in esophageal adenocarcinoma through p53-dependent downregulation of survivin. J Cell Biochem 2019; 120:2070-2077. [PMID: 30318638 DOI: 10.1002/jcb.27515] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 07/27/2018] [Indexed: 01/24/2023]
Abstract
Many cancer drugs have been developed to control tumor growth by inducing cancer cell apoptosis. However, several intracellular barriers could fail this attempt. One of these barrier is high expression of survivin. Survivin can interfere caspase activation and thereby abort apoptosis. In this study, we found that CCN1 suppressed the survivin expression in tumor cells of esophageal adenocarcinoma (EAC) and thus allowed apoptosis to finish. Furthermore, we demonstrated that this downregulation was dependent on p53 phosphorylation at Ser20, and CCN1 induced EAC cell apoptosis through the activation of p53.
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Affiliation(s)
- Tong Dang
- Inner Mongolia Institute of Digestive Diseases, The Second Affiliated Hospital of Baotou Medical College, Inner Mongolia University of Science and Technology, Baotou, Inner Mongolia, China
| | - Cristina Modak
- Laboratory of Gastrointestinal Injury and Cancer, VA Long Beach Healthcare System, Long Beach, California
| | - Xiemei Meng
- Inner Mongolia Institute of Digestive Diseases, The Second Affiliated Hospital of Baotou Medical College, Inner Mongolia University of Science and Technology, Baotou, Inner Mongolia, China
| | - Jinbao Wu
- Inner Mongolia Institute of Digestive Diseases, The Second Affiliated Hospital of Baotou Medical College, Inner Mongolia University of Science and Technology, Baotou, Inner Mongolia, China
| | - Reinier Narvaez
- Laboratory of Gastrointestinal Injury and Cancer, VA Long Beach Healthcare System, Long Beach, California
| | - Jianyuan Chai
- Inner Mongolia Institute of Digestive Diseases, The Second Affiliated Hospital of Baotou Medical College, Inner Mongolia University of Science and Technology, Baotou, Inner Mongolia, China.,Laboratory of Gastrointestinal Injury and Cancer, VA Long Beach Healthcare System, Long Beach, California.,Department of Medicine, College of Medicine, University of California, Irvine, California
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26
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Barrera-Vázquez OS, Cancio-Lonches C, Hernández-González O, Chávez-Munguia B, Villegas-Sepúlveda N, Gutiérrez-Escolano AL. The feline calicivirus leader of the capsid protein causes survivin and XIAP downregulation and apoptosis. Virology 2018; 527:146-158. [PMID: 30529563 DOI: 10.1016/j.virol.2018.11.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/27/2018] [Accepted: 11/27/2018] [Indexed: 01/29/2023]
Abstract
Calicivirus infection causes intrinsic apoptosis, leading to viral propagation in the host. During murine norovirus infection, a reduction in the anti-apoptotic protein survivin has been documented. Here we report that in feline calicivirus infection, a downregulation of the anti-apoptotic proteins survivin and XIAP occur, which correlates with the translocation of the pro-apoptotic protein Smac/DIABLO from the mitochondria to the cytoplasm and the activation of caspase-3. Inhibition of survivin degradation by lactacystin treatment caused a delay in apoptosis progression, reducing virus release, without affecting virus production. However, the overexpression of survivin caused a negative effect in viral progeny production. Overexpression of the leader of the capsid protein (LC), but not of the protease-polymerase NS6/7, results in the downregulation of survivin and XIAP, caspase activation and mitochondrial damage. These results indicate that LC is responsible for the induction of apoptosis in transfected cells and most probably in FCV infection.
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Affiliation(s)
- Oscar Salvador Barrera-Vázquez
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Av. IPN 2508. Col. San Pedro Zacatenco, México, D.F CP 07360, Mexico
| | - Clotilde Cancio-Lonches
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Av. IPN 2508. Col. San Pedro Zacatenco, México, D.F CP 07360, Mexico
| | - Olivia Hernández-González
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Av. IPN 2508. Col. San Pedro Zacatenco, México, D.F CP 07360, Mexico
| | - Bibiana Chávez-Munguia
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Av. IPN 2508. Col. San Pedro Zacatenco, México, D.F CP 07360, Mexico
| | - Nicolás Villegas-Sepúlveda
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del IPN, México City, Mexico
| | - Ana Lorena Gutiérrez-Escolano
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Av. IPN 2508. Col. San Pedro Zacatenco, México, D.F CP 07360, Mexico..
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27
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Nikkhoo A, Rostami N, Hojjat-Farsangi M, Azizi G, Yousefi B, Ghalamfarsa G, Jadidi-Niaragh F. Smac mimetics as novel promising modulators of apoptosis in the treatment of breast cancer. J Cell Biochem 2018; 120:9300-9314. [PMID: 30506843 DOI: 10.1002/jcb.28205] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 11/15/2018] [Indexed: 12/11/2022]
Abstract
Breast cancer is the most prevalent cancer in women. Despite improvements in treatment, the rate of breast cancer-related deaths is still high, and this issue needs further, accurate investigations. Although several treatment options are available, none of them are efficient for complete remission, particularly in advanced stages of the disease. It is known that cancerous cells have dysregulated apoptosis-related pathways, by which they can remain alive for a long time, expand freely, and escape from apoptosis-inducing drugs or antitumor immune responses. Therefore, modulation of apoptosis resistance in cancer cells may be an efficient strategy to overcome current problems faced in the development of immunotherapeutic approaches for the treatment of breast cancer. The inhibitors of apoptosis protein (IAPs) are important targets for cancer therapy because it has been shown that these molecules are overexpressed and highly active in various cancer cells and suppress apoptosis process in malignant cells by blockage of caspase proteins. There is evidence of Smac mimetics efficacy as a single agent; however, recent studies have indicated the efficacy of current anticancer immunotherapeutic approaches when combined with Smac mimetics, which are potent inhibitors of IAPs and synthesized mimicking Smac/Diablo molecules. In this review, we are going to discuss the efficacy of treatment of breast cancer by Smac mimetics alone or in combination with other therapeutics.
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Affiliation(s)
- Afshin Nikkhoo
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Narges Rostami
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Hojjat-Farsangi
- Department of Oncology-Pathology, Immune and Gene therapy Lab, Cancer Center Karolinska (CCK), Karolinska University Hospital Solna and Karolinska Institute, Stockholm, Sweden.,Department of Immunology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
| | - Gholamreza Azizi
- Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Bahman Yousefi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ghasem Ghalamfarsa
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Farhad Jadidi-Niaragh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Immunology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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28
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Campbell GR, Bruckman RS, Chu YL, Trout RN, Spector SA. SMAC Mimetics Induce Autophagy-Dependent Apoptosis of HIV-1-Infected Resting Memory CD4+ T Cells. Cell Host Microbe 2018; 24:689-702.e7. [PMID: 30344003 PMCID: PMC6250054 DOI: 10.1016/j.chom.2018.09.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 06/15/2018] [Accepted: 09/11/2018] [Indexed: 12/18/2022]
Abstract
Long-lived resting memory CD4+ T cells (TCM) are a major reservoir of latent HIV infection. We hypothesized that latent HIV-TCM cells are maintained by aberrant expression of cell survival factors, including XIAP, BIRC2/cIAP1, and beclin-1. DIABLO/SMAC mimetics are therapeutic agents that compromise cell survival by hijacking host apoptotic machinery. We found that DIABLO/SMAC mimetics (birinapant, GDC-0152, and embelin) selectively kill HIV-TCM without increasing virus production or targeting uninfected TCM. Treatment of HIV-TCM with DIABLO/SMAC mimetics promoted XIAP and BIRC2 degradation, which triggered autophagy and the formation of a cell death complex consisting of pro-apoptotic (FADD, RIPK1, RIPK3, and caspase 8) and autophagy (ATG5, ATG7, and SQSTM1) proteins. Genetic or pharmacological inhibition of autophagy induction, but not autophagy-mediated degradation, abrogated this interaction and subsequent cell death. Our findings identify a mechanism whereby DIABLO/SMAC mimetics exploit autophagy and apoptotic machinery to selectively induce killing of HIV-TCM without viral reactivation while sparing uninfected cells.
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Affiliation(s)
- Grant R Campbell
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - Rachel S Bruckman
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - Yen-Lin Chu
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - Rodney N Trout
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - Stephen A Spector
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA; Rady Children's Hospital, San Diego, CA 92123, USA.
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Li BX, Wang HB, Qiu MZ, Luo QY, Yi HJ, Yan XL, Pan WT, Yuan LP, Zhang YX, Xu JH, Zhang L, Yang DJ. Novel smac mimetic APG-1387 elicits ovarian cancer cell killing through TNF-alpha, Ripoptosome and autophagy mediated cell death pathway. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2018. [PMID: 29530056 PMCID: PMC5848599 DOI: 10.1186/s13046-018-0703-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Ovarian cancer is a deadly disease. Inhibitors of apoptosis proteins (IAPs) are key regulators of apoptosis and are frequently dysregulated in ovarian cancer. Overexpression of IAPs proteins has been correlated with tumorigenesis, treatment resistance and poor prognosis. Reinstalling functional cell death machinery by pharmacological inhibition of IAPs proteins may represent an attractive therapeutic strategy for treatment of ovarian cancer. Methods CCK-8 and colony formation assay was performed to examine cytotoxic activity. Apoptosis was analyzed by fluorescence microscopy, flow cytometry and TUNEL assay. Elisa assay was used to determine TNFα protein. Caspase activity assay was used for caspase activation evaluation. Immunoprecipitation and siRNA interference were carried out for functional analysis. Western blotting analysis were carried out to test protein expression. Ovarian cancer cell xenograft nude mice model was used for in vivo efficacy evaluation. Results APG-1387 demonstrated potent inhibitory effect on ovarian cancer cell growth and clonogenic cell survival. APG-1387 induced RIP1- and TNFα-dependent apoptotic cell death in ovarian cancer through downregulation of IAPs proteins and induction of caspase-8/FADD/RIP1 complex, which drives caspase-8 activation. NF-κB signaling pathway was activated upon APG-1387 treatment and RIP1 contributed to NF-κB activation. APG-1387 induced cytoprotective autophagy while triggering apoptosis in ovarian cancer cells and inhibition of autophagy enhanced APG-1387-induced apoptotic cell death. APG-1387 exhibited potent antitumor activity against established human ovarian cancer xenografts. Conclusions Our results demonstrate that APG-1387 targets IAPs proteins to potently elicit apoptotic cell death in vitro and in vivo, and provide mechanistic and applicable rationale for future clinical evaluation of APG-1387 in ovarian cancer.
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Affiliation(s)
- Bao-Xia Li
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Heng-Bang Wang
- Department of Pharmacology, Fujian Provincial Key Laboratory of Natural Medicine Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350108, China.,Ascentage Pharma Group Corp., Ltd., Taizhou, 225309, China
| | - Miao-Zhen Qiu
- Department of Medical Oncology, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, 510060, China
| | - Qiu-Yun Luo
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Han-Jie Yi
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Xiang-Lei Yan
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Wen-Tao Pan
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Lu-Ping Yuan
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Yu-Xin Zhang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Jian-Hua Xu
- Department of Pharmacology, Fujian Provincial Key Laboratory of Natural Medicine Pharmacology, School of Pharmacy, Fujian Medical University, Fuzhou, 350108, China.
| | - Lin Zhang
- Departments of Clinical Laboratory, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, China.
| | - Da-Jun Yang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China. .,Ascentage Pharma Group Corp., Ltd., Taizhou, 225309, China.
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30
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Khan Z, Khan AA, Yadav H, Prasad GBKS, Bisen PS. Survivin, a molecular target for therapeutic interventions in squamous cell carcinoma. Cell Mol Biol Lett 2017; 22:8. [PMID: 28536639 PMCID: PMC5415770 DOI: 10.1186/s11658-017-0038-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 03/27/2017] [Indexed: 12/14/2022] Open
Abstract
Squamous cell carcinoma (SCC) is the most common cancer worldwide. The treatment of locally advanced disease generally requires various combinations of radiotherapy, surgery, and systemic therapy. Despite aggressive multimodal treatment, most of the patients relapse. Identification of molecules that sustain cancer cell growth and survival has made molecular targeting a feasible therapeutic strategy. Survivin is a member of the Inhibitor of Apoptosis Protein (IAP) family, which is overexpressed in most of the malignancies including SCC and totally absent in most of the normal tissues. This feature makes survivin an ideal target for cancer therapy. It orchestrates several important mechanisms to support cancer cell survival including inhibition of apoptosis and regulation of cell division. Overexpression of survivin in tumors is also associated with poor prognosis, aggressive tumor behavior, resistance to therapy, and high tumor recurrence. Various strategies have been developed to target survivin expression in cancer cells, and their effects on apoptosis induction and tumor growth attenuation have been demonstrated. In this review, we discuss recent advances in therapeutic potential of survivin in cancer treatment.
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Affiliation(s)
- Zakir Khan
- School of Studies in Biotechnology, Jiwaji University, Gwalior, 474001 MP India.,Department of Biomedical Sciences, Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
| | - Abdul Arif Khan
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Hariom Yadav
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892 USA
| | | | - Prakash Singh Bisen
- School of Studies in Biotechnology, Jiwaji University, Gwalior, 474001 MP India
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31
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Attaran-Bandarabadi F, Abhari BA, Neishabouri SH, Davoodi J. Integrity of XIAP is essential for effective activity recovery of apoptosome and its downstream caspases by Smac/Diablo. Int J Biol Macromol 2017; 101:283-289. [PMID: 28322955 DOI: 10.1016/j.ijbiomac.2017.03.088] [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] [Received: 12/30/2016] [Revised: 03/15/2017] [Accepted: 03/16/2017] [Indexed: 01/20/2023]
Abstract
Contribution of individual BIR domains to Smac antagonism is investigated. Ammonium citrate was used to activate caspase-9 and pro-caspase-9 (D315, D330/A). However, the presence of citrate resulted in autoproteolysis of pro-caspase-9 and its inhibition by XIAP BIR3, which was not observed for apoptosome activated pro-caspase-9 indicating abnormal behavior of pro-caspase-9 in kosmotropic citrate salt. Thus, we used Apaf-1(residues 1-591) to activate caspase-9 through the formation of mini-apoptosome instead. Inhibition of apoptosome by XIAP BIR-1-2-3 was observed to be similar to that of BIR3 indicating that the cleavage of XIAP does not affect its potency. However, BIR1-2-3 was more prone to Smac antagonism due to simultaneous interaction of two BIR domains from XIAP with two N-terminal binding sites of Smac. Therefore, despite the role in caspase-9 activation, Apaf-1 does not influence caspase-9 inhibition by XIAP. In addition, caspase-3, -7 and -9 activity recovery by Smac protein and peptide were more efficient for BIR1-2-3 than for BIR1-2. Consequently, it can be proposed that the presence of multiple BIR domains for XIAP among different species along with dimeric nature of Smac are evolutionary designed to strengthen the antagonistic activity of Smac culminating in efficient induction of cell death.
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Affiliation(s)
| | | | | | - Jamshid Davoodi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
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32
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Hashim YM, Vangveravong S, Sankpal NV, Binder PS, Liu J, Goedegebuure SP, Mach RH, Spitzer D, Hawkins WG. The Targeted SMAC Mimetic SW IV-134 is a strong enhancer of standard chemotherapy in pancreatic cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2017; 36:14. [PMID: 28095907 PMCID: PMC5240213 DOI: 10.1186/s13046-016-0470-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 12/05/2016] [Indexed: 02/07/2023]
Abstract
Background Pancreatic cancer is a lethal malignancy that frequently acquires resistance to conventional chemotherapies often associated with overexpression of inhibitors of apoptosis proteins (IAPs). We have recently described a novel means to deliver second mitochondria-derived activator of caspases (SMAC) mimetics selectively to cancer cells employing the sigma-2 ligand/receptor interaction. The intrinsic death pathway agonist SMAC offers an excellent opportunity to counteract the anti-apoptotic activity of IAPs. SMAC mimetics have been used to sensitize several cancer types to chemotherapeutic agents but cancer-selective delivery and appropriate cellular localization have not yet been considered. In our current study, we tested the ability of the sigma-2/SMAC drug conjugate SW IV-134 to sensitize pancreatic cancer cells to gemcitabine. Methods Using the targeted SMAC mimetic SW IV-134, inhibition of the X-linked inhibitor of apoptosis proteins (XIAP) was induced pharmacologically and its impact on cell viability was studied alone and in combination with gemcitabine. Pathway analyses were performed by assessing caspase activation, PARP cleavage and membrane blebbing (Annexin-V), key components of apoptotic cell death. Single-agent treatment regimens were compared with combination therapy in a preclinical mouse model of pancreatic cancer. Results The sensitizing effect of XIAP interference toward gemcitabine was confirmed via pharmacological intervention using our recently designed, targeted SMAC mimetic SW IV-134 across a wide range of commonly used pancreatic cancer cell lines at concentrations where the individual drugs showed only minimal activity. On a mechanistic level, we identified involvement of key components of the apoptosis machinery during cell death execution. Furthermore, combination therapy proved superior in decreasing the tumor burden and extending the lives of the animals in a preclinical mouse model of pancreatic cancer. Conclusion We believe that the strong sensitizing capacity of SW IV-134 in combination with clinically relevant doses of gemcitabine represents a promising treatment option that warrants clinical evaluation. Electronic supplementary material The online version of this article (doi:10.1186/s13046-016-0470-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yassar M Hashim
- Department of Surgery, Barnes-Jewish Hospital and Washington University School of Medicine St. Louis, 660 S. Euclid Ave, Box 8109, Saint Louis, MO, 63110, USA.,Present Address: Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd, 8215-NT, Los Angeles, CA, 90048, USA
| | - Suwanna Vangveravong
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Narendra V Sankpal
- Department of Surgery, Barnes-Jewish Hospital and Washington University School of Medicine St. Louis, 660 S. Euclid Ave, Box 8109, Saint Louis, MO, 63110, USA
| | - Pratibha S Binder
- Division of Gynecologic Oncology, Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, USA
| | - Jingxia Liu
- Department of Surgery, Barnes-Jewish Hospital and Washington University School of Medicine St. Louis, 660 S. Euclid Ave, Box 8109, Saint Louis, MO, 63110, USA.,Division of Public Health Sciences, Section of Oncologic Biostatistics, Washington University School of Medicine, St. Louis, MO, USA
| | - S Peter Goedegebuure
- Department of Surgery, Barnes-Jewish Hospital and Washington University School of Medicine St. Louis, 660 S. Euclid Ave, Box 8109, Saint Louis, MO, 63110, USA.,Alvin J. Siteman Cancer Center, St. Louis, MO, USA
| | - Robert H Mach
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Dirk Spitzer
- Department of Surgery, Barnes-Jewish Hospital and Washington University School of Medicine St. Louis, 660 S. Euclid Ave, Box 8109, Saint Louis, MO, 63110, USA.,Alvin J. Siteman Cancer Center, St. Louis, MO, USA
| | - William G Hawkins
- Department of Surgery, Barnes-Jewish Hospital and Washington University School of Medicine St. Louis, 660 S. Euclid Ave, Box 8109, Saint Louis, MO, 63110, USA. .,Alvin J. Siteman Cancer Center, St. Louis, MO, USA.
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Abstract
Inhibitor of Apoptosis (IAP) proteins block programmed cell death and are expressed at high levels in various human cancers, thus making them attractive targets for cancer drug development. Second mitochondrial activator of caspases (Smac) mimetics are small-molecule inhibitors that mimic Smac, an endogenous antagonist of IAP proteins. Preclinical studies have shown that Smac mimetics can directly trigger cancer cell death or, even more importantly, sensitize tumor cells for various cytotoxic therapies, including conventional chemotherapy, radiotherapy, or novel agents. Currently, several Smac mimetics are under evaluation in early clinical trials as monotherapy or in rational combinations (i.e., GDC-0917/CUDC-427, LCL161, AT-406/Debio1143, HGS1029, and TL32711/birinapant). This review discusses the promise as well as some challenges at the translational interface of exploiting Smac mimetics as cancer therapeutics.
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Affiliation(s)
- Simone Fulda
- Institute for Experimental Cancer Research in Pediatrics, Goethe-University, Frankfurt, Germany. German Cancer Consortium (DKTK), Heidelberg, Germany. German Cancer Research Center (DKFZ), Heidelberg, Germany.
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Clarification of the molecular pathway of Taiwan local pomegranate fruit juice underlying the inhibition of urinary bladder urothelial carcinoma cell by proteomics strategy. Altern Ther Health Med 2016; 16:96. [PMID: 26955879 PMCID: PMC4784391 DOI: 10.1186/s12906-016-1071-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 03/02/2016] [Indexed: 02/06/2023]
Abstract
Background Pomegranate fruit has been shown to exhibit the inhibitory activity against prostate cancer and lung cancer in vitro and in vivo, which might be a resource for chemoprevention and chemotherapy of cancer. Our previous documented findings indicated that treatment of urinary bladder urothelial carcinoma cell with the ethanol extract isolated from the juice of pomegranate fruit grown in Taiwan could inhibit tumor cell. In this study we intended to uncover the molecular pathway underlying anti-cancer efficacy of Taiwan pomegranate fruit juice against urinary bladder urothelial carcinoma. Methods We exploited two-dimensional gel electrophoresis coupled with tandem mass spectrometry to find the de-regulated proteins. Western immunoblotting was used to confirm the results collected from proteomics study. Results Comparative proteomics indicated that 20 proteins were differentially expressed in ethanol extract-treated T24 cells with 19 up-regulated and 1 down-regulated proteins. These de-regulated proteins were involved in apoptosis, cytoskeleton regulation, cell proliferation, proteasome activity and aerobic glycolysis. Further studies on signaling pathway demonstrated that ethanol extract treatment might inhibit urinary bladder urothelial carcinoma cell proliferation through restriction of PTEN/AKT/mTORC1 pathway via profilin 1 up-regulation. It also might evoke cell apoptosis through Diablo over-expression. Conclusions The results of this study provide a global picture to further investigate the anticancer molecular mechanism of pomegranate fruit. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1071-7) contains supplementary material, which is available to authorized users.
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35
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The activator of apoptosis Smac-DIABLO acts as a tetramer in solution. Biophys J 2015; 108:714-23. [PMID: 25650938 DOI: 10.1016/j.bpj.2014.11.3471] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 11/24/2014] [Accepted: 11/26/2014] [Indexed: 11/21/2022] Open
Abstract
Smac-DIABLO in its mature form (20.8 kDa) binds to baculoviral IAP repeat (BIR) domains of inhibitor of apoptosis proteins (IAPs) releasing their inhibitory effects on caspases, thus promoting cell death. Despite its apparent molecular mass (∼100 kDa), Smac-DIABLO was held to be a dimer in solution, simultaneously targeting two distinct BIR domains. We report an extensive biophysical characterization of the protein alone and in complex with the X-linked IAP (XIAP)-BIR2-BIR3 domains. Our data show that Smac-DIABLO adopts a tetrameric assembly in solution and that the tetramer is able to bind two BIR2-BIR3 pairs of domains. Our small-angle x-ray scattering-based tetrameric model of Smac-DIABLO/BIR2-BIR3 highlights some conformational freedom of the complex that may be related to optimization of IAPs binding.
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36
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Perez HL, Chaudhry C, Emanuel SL, Fanslau C, Fargnoli J, Gan J, Kim KS, Lei M, Naglich JG, Traeger SC, Vuppugalla R, Wei DD, Vite GD, Talbott RL, Borzilleri RM. Discovery of Potent Heterodimeric Antagonists of Inhibitor of Apoptosis Proteins (IAPs) with Sustained Antitumor Activity. J Med Chem 2015; 58:1556-62. [DOI: 10.1021/jm501482t] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Heidi L. Perez
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Charu Chaudhry
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Stuart L. Emanuel
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Caroline Fanslau
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Joseph Fargnoli
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Jinping Gan
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Kyoung S. Kim
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Ming Lei
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Joseph G. Naglich
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Sarah C. Traeger
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Ragini Vuppugalla
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Donna D. Wei
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Gregory D. Vite
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Randy L. Talbott
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Robert M. Borzilleri
- Bristol-Myers Squibb Research, P.O. Box 4000, Princeton, New Jersey 08543, United States
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Xiong S, Mu T, Wang G, Jiang X. Mitochondria-mediated apoptosis in mammals. Protein Cell 2014; 5:737-49. [PMID: 25073422 PMCID: PMC4180462 DOI: 10.1007/s13238-014-0089-1] [Citation(s) in RCA: 276] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 07/08/2014] [Indexed: 01/06/2023] Open
Abstract
The mitochondria-mediated caspase activation pathway is a major apoptotic pathway characterized by mitochondrial outer membrane permeabilization (MOMP) and subsequent release of cytochrome c into the cytoplasm to activate caspases. MOMP is regulated by the Bcl-2 family of proteins. This pathway plays important roles not only in normal development, maintenance of tissue homeostasis and the regulation of immune system, but also in human diseases such as immune disorders, neurodegeneration and cancer. In the past decades the molecular basis of this pathway and the regulatory mechanism have been comprehensively studied, yet a great deal of new evidence indicates that cytochrome c release from mitochondria does not always lead to irreversible cell death, and that caspase activation can also have non-death functions. Thus, many unsolved questions and new challenges are still remaining. Furthermore, the dysfunction of this pathway involved in cancer development is obvious, and targeting the pathway as a therapeutic strategy has been extensively explored, but the efficacy of the targeted therapies is still under development. In this review we will discuss the mitochondria-mediated apoptosis pathway and its physiological roles and therapeutic implications.
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Affiliation(s)
- Shunbin Xiong
- Department of Genetics, The University of Texas, M.D. Anderson Cancer Center, Houston, TX, 77030, USA
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Sau S, Banerjee R. Cationic lipid-conjugated dexamethasone as a selective antitumor agent. Eur J Med Chem 2014; 83:433-47. [PMID: 24992071 DOI: 10.1016/j.ejmech.2014.06.051] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 06/23/2014] [Accepted: 06/24/2014] [Indexed: 01/07/2023]
Abstract
Dexamethasone (Dex) is one of the highly potent synthetic glucocorticoids. It exhibits prominent anti-inflammatory but moderate anti-proliferative activities. It is widely used along side chemotherapy to alleviate toxic side effects. Additionally, Dex is also a potent inducer of gluconeogenesis. However, its overuse critically desensitizes cells against chemotherapy. Herein, we report on the development of a new class of cationic lipid-Dex conjugates in which the C-8 carbon chain analogue (DX8) exhibited glucocorticoid receptor (GR)-mediated, caspase-3-assisted, cancer cell-selective anti-proliferative activity. Melanoma tumors in DX8-treated mice exhibited significantly reduced tumor aggressiveness with respect to tumors in Dex-treated mice. Tumor lysates prepared from DX8-treated group showed elevated levels of p53. DX8-treated cancer cells showed clear degradation of kinase JAK3/STAT3 protein levels. Additionally, DX8-treatment decreased the level of VEGFR2 in tumor-endothelial cells implying DX8's anti-proliferative roles in both tumor cells and tumor neovascular cells. Collectively, our results demonstrate potent anti-angiogenic, and selective JAK3/STAT3 down-regulating anticancer characteristics of DX8, a new dexamethasone-based antitumor molecule.
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Affiliation(s)
- Samaresh Sau
- Biomaterials Group, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Tarnaka, Uppal Road, Hyderabad, Andhra Pradesh 500007, India
| | - Rajkumar Banerjee
- Biomaterials Group, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Tarnaka, Uppal Road, Hyderabad, Andhra Pradesh 500007, India; Academy of Scientific and Innovative Research (AcSIR), 2 Rafi Marg, New Delhi 110 001, India.
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Guicciardi ME, Werneburg NW, Bronk SF, Franke A, Yagita H, Thomas G, Gores GJ. Cellular inhibitor of apoptosis (cIAP)-mediated ubiquitination of phosphofurin acidic cluster sorting protein 2 (PACS-2) negatively regulates tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) cytotoxicity. PLoS One 2014; 9:e92124. [PMID: 24633224 PMCID: PMC3954888 DOI: 10.1371/journal.pone.0092124] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 02/18/2014] [Indexed: 01/24/2023] Open
Abstract
Lysosomal membrane permeabilization is an essential step in TRAIL-induced apoptosis of liver cancer cell lines. TRAIL-induced lysosomal membrane permeabilization is mediated by the multifunctional sorting protein PACS-2 and repressed by the E3 ligases cIAP-1 and cIAP-2. Despite the opposing roles for PACS-2 and cIAPs in TRAIL-induced apoptosis, an interaction between these proteins has yet to be examined. Herein, we report that cIAP-1 and cIAP-2 confer TRAIL resistance to hepatobiliary cancer cell lines by reducing PACS-2 levels. Under basal conditions, PACS-2 underwent K48-linked poly-ubiquitination, resulting in PACS-2 proteasomal degradation. Biochemical assays showed cIAP-1 and cIAP-2 interacted with PACS-2 in vitro and co-immunoprecipitation studies demonstrated that the two cIAPs bound PACS-2 in vivo. More importantly, both cIAP-1 and cIAP-2 directly mediated PACS-2 ubiquitination in a cell-free assay. Single c-Iap-1 or c-Iap-2 gene knock-outs in mouse hepatocytes did not lead to PACS-2 accumulation. However, deletion of both cIAP-1 and cIAP-2 reduced PACS-2 ubiquitination, which increased PACS-2 levels and sensitized HuH-7 cells to TRAIL-induced lysosomal membrane permeabilization and apoptosis. Correspondingly, deletion of cIAPs sensitized wild-type, but not PACS-2-deficient hepatocarcinoma cells or Pacs-2−/− mouse hepatocytes to TRAIL-induced apoptosis. Together, these data suggest cIAPs constitutively downregulate PACS-2 by polyubiquitination and proteasomal degradation, thereby restraining TRAIL-induced killing of liver cancer cells.
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Affiliation(s)
- Maria Eugenia Guicciardi
- Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Nathan W. Werneburg
- Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Steven F. Bronk
- Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Adrian Franke
- Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Hideo Yagita
- Department of Immunology, School of Medicine, Juntendo University, Tokyo, Japan
| | - Gary Thomas
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Gregory J. Gores
- Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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Abstract
Inhibitor of apoptosis (IAP) proteins interface with, and regulate a large number of, cell signaling pathways. If there is a common theme to these pathways, it is that they are involved in the development of the immune system, immune responses, and unsurprisingly, given their name, cell death. Beyond that it is difficult to discover an underlying logic because sometimes IAPs are required to inhibit or prevent signaling, whereas in other cases they are required for signaling to take place. In whatever role they play, they are recruited into signaling complexes and function as ubiquitin E3 ligases, via their RING domains. This review discusses IAP regulation of signaling pathways and focuses on the mammalian IAPs, XIAP, c-IAP1, and c-IAP2, with a particular emphasis on techniques and methods that were used to uncover their roles. We also provide a perspective on targeting IAP proteins for therapeutic intervention and methods used to define the clinical relevance of IAP proteins.
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Affiliation(s)
- John Silke
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia.
| | - Domagoj Vucic
- Department of Early Discovery Biochemistry, Genentech, Inc., South San Francisco, California, USA.
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41
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Fulda S. Molecular pathways: targeting inhibitor of apoptosis proteins in cancer--from molecular mechanism to therapeutic application. Clin Cancer Res 2013; 20:289-95. [PMID: 24270683 DOI: 10.1158/1078-0432.ccr-13-0227] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Inhibitor of apoptosis (IAP) proteins play a critical role in the control of survival and cell death by regulating key signaling events such as caspase activation and NF-κB signaling. Because aberrantly high expression of IAP proteins represents a frequent oncogenic event in human cancers, therapeutic targeting of IAP proteins is considered as a promising approach. Several small-molecule pharmacologic inhibitors of IAP proteins that mimic the binding domain of the endogenous IAP antagonist second mitochondrial activator of caspases (Smac) to IAP proteins have been developed over the past few years. IAP antagonists have been shown in various preclinical cancer models to either directly initiate cell death or, alternatively, to prime cancer cells for cytotoxic therapies by lowering the threshold for cell death induction. IAP antagonists (i.e., GDC-0917/CUDC-427, LCL161, AT-406, HGS1029, and TL32711) are currently under evaluation in early clinical trials alone or in combination regimens. Thus, the concept to therapeutically target IAP proteins in human cancer has in principle been successfully transferred into a clinical setting and warrants further evaluation as a treatment approach.
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Affiliation(s)
- Simone Fulda
- Author's Affiliation: Institute for Experimental Cancer Research in Pediatrics, Goethe-University, Frankfurt, Germany
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KO YUJIN, JEONG JINWOO, CHOI YUNGHYUN, RYU CHUNGHO. Soy soluble polysaccharide induces apoptosis in HCT-116 human colon cancer cells via reactive oxygen species generation. Mol Med Rep 2013; 8:1767-72. [DOI: 10.3892/mmr.2013.1725] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 09/26/2013] [Indexed: 11/05/2022] Open
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Jeong CH, Chun KS, Kundu J, Park B. Phosphorylation of Smac by Akt promotes the caspase-3 activation during etoposide-induced apoptosis in HeLa cells. Mol Carcinog 2013; 54:83-92. [DOI: 10.1002/mc.22075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 07/01/2013] [Accepted: 07/08/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Chul-Ho Jeong
- College of Pharmacy; Keimyung University; Daegu Republic of Korea
| | - Kyung-Soo Chun
- College of Pharmacy; Keimyung University; Daegu Republic of Korea
| | - Juthika Kundu
- College of Pharmacy; Keimyung University; Daegu Republic of Korea
| | - Byoungduck Park
- College of Pharmacy; Keimyung University; Daegu Republic of Korea
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Lin YF, Lai TC, Chang CK, Chen CL, Huang MS, Yang CJ, Liu HG, Dong JJ, Chou YA, Teng KH, Chen SH, Tian WT, Jan YH, Hsiao M, Liang PH. Targeting the XIAP/caspase-7 complex selectively kills caspase-3-deficient malignancies. J Clin Invest 2013; 123:3861-75. [PMID: 23979166 DOI: 10.1172/jci67951] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 06/21/2013] [Indexed: 01/06/2023] Open
Abstract
Caspase-3 downregulation (CASP3/DR) in tumors frequently confers resistance to cancer therapy and is significantly correlated with a poor prognosis in cancer patients. Because CASP3/DR cancer cells rely heavily on the activity of caspase-7 (CASP7) to initiate apoptosis, inhibition of activated CASP7 (p19/p12-CASP7) by X-linked inhibitor of apoptosis protein (XIAP) is a potential mechanism by which apoptosis is prevented in those cancer cells. Here, we identify the pocket surrounding the Cys246 residue of p19/p12-CASP7 as a target for the development of a protein-protein interaction (PPI) inhibitor of the XIAP:p19/p12-CASP7 complex. Interrupting this PPI directly triggered CASP7-dependent apoptotic signaling that bypassed the activation of the apical caspases and selectively killed CASP3/DR malignancies in vitro and in vivo without adverse side effects in nontumor cells. Importantly, CASP3/DR combined with p19/p12-CASP7 accumulation correlated with the aggressive evolution of clinical malignancies and a poor prognosis in cancer patients. Moreover, targeting of this PPI effectively killed cancer cells with multidrug resistance due to microRNA let-7a-1-mediated CASP3/DR and resensitized cancer cells to chemotherapy-induced apoptosis. These findings not only provide an opportunity to treat CASP3/DR malignancies by targeting the XIAP:p19/p12-CASP7 complex, but also elucidate the molecular mechanism underlying CASP3/DR in cancers.
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Affiliation(s)
- Yuan-Feng Lin
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
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Liu BH, Chen L, Li SR, Wang ZX, Cheng WG. Smac/DIABLO regulates the apoptosis of hypertrophic scar fibroblasts. Int J Mol Med 2013; 32:615-22. [PMID: 23857156 DOI: 10.3892/ijmm.2013.1442] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 06/10/2013] [Indexed: 11/06/2022] Open
Abstract
In abnormal skin wound healing, hypertrophic scars (HS) are characterized by excessive fibroblast hypercellularity and an overproduction of collagen, leading to atypical extracellular matrix (ECM) remodeling. Although the exact mechanisms of HS remain unclear, decreased HS fibroblast (HSFB) apoptosis and increased proliferation are evident in the development of HS. In this study, the contribution of the second mitochondria-derived activator of caspases/direct inhibitor of apoptosis protein (IAP)-binding protein with a low isoelectric point (pI) (Smac/DIABLO), an apoptosis-promoting protein released from the mitochondria, was investigated in human normal skin and HSFB cultures. The expression of Smac/DIABLO is usually decreased in many malignant tumors compared with normal tissues. Immunohistochemical analysis of skin tissues and the western blot analyses of fibroblasts revealed that the expression of Smac/DIABLO was lower in HS tissues compared with normal skin tissues. Of note, adenovirus-mediated Smac/DIABLO overexpression in the cultured HSFBs significantly reduced cell proliferation, as detected by the cell counting kit-8, and increased caspase-3 and -9 activity, as detected by spectrofluorimetry. In addition, it increased apoptosis, as detected by fluorescence-activated cell sorting (FACS). Furthermore, we found that the silencing of Smac with siRNA in the HSFBs induced a noticeable decrease in caspase-3 and -9 activity, leading to a significant reduction in apoptosis. In addition, the mRNA expression of type I and III pro-collagen detected in the HSFBs was significantly increased following the silencing of Smac with siRNA and was inhibited following Smac/DIABLO overexpression, as shown by real-time RT-PCR. In conclusion, Smac/DIABLO decreases the proliferation and increases the apoptosis of HSFBs. To our knowledge, the data from our study suggest for the first time that Smac/DIABLO is a novel therapeutic target for HS.
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Affiliation(s)
- Bao-Heng Liu
- Department of Plastic and Reconstructive Surgery, Southwest Hospital, The Third Military Medical University, Chongqing 400038, P.R. China
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Hu Q, Wu D, Chen W, Yan Z, Shi Y. Proteolytic processing of the caspase-9 zymogen is required for apoptosome-mediated activation of caspase-9. J Biol Chem 2013; 288:15142-7. [PMID: 23572523 DOI: 10.1074/jbc.m112.441568] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Maturation of the single-chain caspase-9 zymogen through autoproteolytic processing is mediated by the Apaf-1 apoptosome at the onset of apoptosis. Processed caspase-9 and the apoptosome form a holoenzyme with robust proteolytic activity that is 2-3 orders of magnitude higher than that of free processed caspase-9. An unresolved important question is the role of caspase-9 processing, with some experimental data suggesting its dispensability. In this study, we demonstrate that, in contrast to wild-type caspase-9, the unprocessed single-chain caspase-9 triple mutant E306A/D315A/D330A (Casp9-TM) could no longer be adequately activated by the apoptosome. Compared with the protease activity of wild-type caspase-9, that of Casp9-TM in the presence of the apoptosome was drastically reduced. The crippled protease activity of Casp9-TM in the presence of the apoptosome is likely attributable to a markedly reduced ability of Casp9-TM to form homodimers. These data identify an essential role for the autoproteolytic processing of caspase-9 in its activation.
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Affiliation(s)
- Qi Hu
- Ministry of Education Key Laboratory for Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences, and School of Medicine, Tsinghua University, Beijing 100084, USA
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5-Phenylselenyl- and 5-methylselenyl-methyl-2'-deoxyuridine induce oxidative stress, DNA damage, and caspase-2-dependent apoptosis in cancer cells. Apoptosis 2012; 17:200-16. [PMID: 22002103 DOI: 10.1007/s10495-011-0665-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In the present study, we investigated the signaling pathways implicated in the induction of apoptosis by two modified nucleosides, 5-phenylselenyl-methyl-2'-deoxyuridine (PhSe-T) and 5-methylselenyl-methyl-2'-deoxyuridine (MeSe-T), using human cancer cell lines. The induction of apoptosis was associated with proteolytic activation of caspase-3 and -9, PARP cleavage, and decreased levels of IAP family members, including c-IAP-1 and c-IAP-2, but had no effect on XIAP and survivin. PhSe-T and MeSe-T also enhanced the activities of caspase-2 and -8, Bid cleavage, and the conformational activation of Bax. Additionally, nucleoside derivative-induced apoptosis was inhibited by the selective inhibitors of caspase-2, -3, -8, and -9 and also by si-RNAs against caspase-2, -3, -8, and -9; however, inhibition of caspase-2 and -3 was more effective at preventing apoptosis than inhibition of caspase-8 and -9. Moreover, the inhibition of caspase-2 activation by the pharmacological inhibitor z-VDVAD-fmk or by the knockdown of protein expression using siRNA suppressed nucleoside derivative-induced caspase-3 activation, but not vice versa. PhSe-T and MeSe-T also induced a Δψ(m) loss via a CsA-insensitive mechanism, ROS production, and DNA damage, including strand breaks. Moreover, ROS scavengers such as NAC, tiron, and quercetin inhibited nucleoside derivative-induced ROS generation and apoptosis by blocking the sequential activation of caspase-2 and -3, indicating the role of ROS in caspase-2-mediated apoptosis. Taken together, these results indicate that caspase-2 acts upstream of caspase-3 and that caspase-2 functions in response to DNA damage in both PhSe-T- and MeSe-T-induced apoptosis. Our results also suggest that ROS are critical regulators of the sequential activation of caspase-2 and -3 in nucleoside derivative-treated cancer cells.
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Phillipps HR, Hurst PR. XIAP: a potential determinant of ovarian follicular fate. Reproduction 2012; 144:165-76. [DOI: 10.1530/rep-12-0142] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
X-linked inhibitor of apoptosis protein (XIAP), a member of the inhibitor of apoptosis protein family, is involved in regulating a number of functions including receptor-mediated intracellular signalling and early development. Its role as an endogenous caspase inhibitor, however, is the most highly characterised. Consequently, this protein has been implicated as an anti-apoptotic factor in the ovary.In vitroandin vivostudies have begun dissecting the stimuli and signalling networks that lead to XIAP upregulation in granulosa cells. The objective of this review is to briefly summarise the current knowledge concerning XIAP and its interactions with different caspases. Furthermore, XIAP's emerging role in the mammalian ovary will be explored and comparison is made with its functions in the mammary gland. Finally, the idea that XIAP may act as a molecular signalling switch in granulosa cells following detachment from underlying layers to promote follicular atresia will be introduced.
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SHIN DONGYEOK, PARK YOUSOO, YANG KWANGMO, KIM GIYOUNG, KIM WUNJAE, HAN MINHO, KANG HOSUNG, CHOI YUNGHYUN. Decitabine, a DNA methyltransferase inhibitor, induces apoptosis in human leukemia cells through intracellular reactive oxygen species generation. Int J Oncol 2012; 41:910-8. [DOI: 10.3892/ijo.2012.1546] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Accepted: 05/16/2012] [Indexed: 11/05/2022] Open
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Icariside II induces apoptosis in U937 acute myeloid leukemia cells: role of inactivation of STAT3-related signaling. PLoS One 2012; 7:e28706. [PMID: 22493659 PMCID: PMC3320887 DOI: 10.1371/journal.pone.0028706] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 11/14/2011] [Indexed: 11/19/2022] Open
Abstract
Background The aim of this study is to determine anti-cancer effect of Icariside II purified from the root of Epimedium koreanum Nakai on human acute myeloid leukemia (AML) cell line U937. Methodology/Principal Findings Icariside II blocked the growth U937 cells in a dose- and time-dependent manner. In this anti-proliferation process, this herb compound rendered the cells susceptible to apoptosis, manifested by enhanced accumulation of sub-G1 cell population and increased the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells. Icariside II was able to activate caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP) in a time-dependent manner. Concurrently, the anti-apoptotic proteins, such as bcl-xL and survivin in U937 cells, were downregulated by Icariside II. In addition, Icariside II could inhibit STAT3 phosphorylation and function and subsequently suppress the activation of Janus activated kinase 2 (JAK2), the upstream activators of STAT3, in a dose- and time-dependent manner. Icariside II also enhanced the expression of protein tyrosine phosphatase (PTP) SH2 domain-containing phosphatase (SHP)-1, and the addition of sodium pervanadate (a PTP inhibitor) prevented Icariside II-induced apoptosis as well as STAT3 inactivation in STAT3 positive U937 cells. Furthermore, silencing SHP-1 using its specific siRNA significantly blocked STAT3 inactivation and apoptosis induced by Icariside II in U937 cells. Conclusions/Significance Our results demonstrated that via targeting STAT3-related signaling, Icariside II sensitizes U937 cells to apoptosis and perhaps serves as a potent chemotherapeutic agent for AML.
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