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Fareed MR, Shoman ME, Hamed MIA, Badr M, Bogari HA, Elhady SS, Ibrahim TS, Abuo-Rahma GEDA, Ali TFS. New Multi-Targeted Antiproliferative Agents: Design and Synthesis of IC261-Based Oxindoles as Potential Tubulin, CK1 and EGFR Inhibitors. Pharmaceuticals (Basel) 2021; 14:1114. [PMID: 34832895 PMCID: PMC8620390 DOI: 10.3390/ph14111114] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/22/2022] Open
Abstract
A series of 3-benzylideneindolin-2-one compounds was designed and synthesized based on combretastatin A-4 and compound IC261, a dual casein kinase (CK1)/tubulin polymerization inhibitor, taking into consideration the pharmacophore required for EGFR-tyrosine kinase inhibition. The new molecular entities provoked significant growth inhibition against PC-3, MCF-7 and COLO-205 at a 10 μM dose. Compounds 6-chloro-3-(2,4,6-trimethoxybenzylidene) indolin-2-one, 4b, and 5-methoxy-3-(2,4,6-trimethoxybenzylidene)indolin-2-one, 4e, showed potent activity against the colon cancer COLO-205 cell line with an IC50 value of 0.2 and 0.3 μM. A mechanistic study demonstrated 4b's efficacy in inhibiting microtubule assembly (IC50 = 1.66 ± 0.08 μM) with potential binding to the colchicine binding site (docking study). With an IC50 of 1.92 ± 0.09 μg/mL, 4b inhibited CK1 almost as well as IC261. Additionally, 4b and 4e were effective inhibitors of EGFR-TK with IC50s of 0.19 μg/mL and 0.40 μg/mL compared to Gifitinib (IC50 = 0.05 μg/mL). Apoptosis was induced in COLO-205 cells treated with 4b, with apoptotic markers dysregulated. Caspase 3 levels were elevated to more than three-fold, while Cytochrome C levels were doubled. The cell cycle was arrested in the pre-G1 phase with extensive cellular accumulation in the pre-G1 phase, confirming apoptosis induction. Levels of cell cycle regulating proteins BAX and Bcl-2 were also defective. The binding interaction patterns of these compounds at the colchicine binding site of tubulin and the Gifitinib binding site of EGFR were verified by molecular docking, which adequately matched the reported experimental result. Hence, 4b and 4e are considered promising potent multitarget agents against colon cancer that require optimization.
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Affiliation(s)
- Momen R. Fareed
- Department of Medicinal Chemistry, Faculty of Pharmacy, Minia University, Minia 61519, Egypt; (M.R.F.); (T.F.S.A.); (G.E.-D.A.A.-R.)
| | - Mai E. Shoman
- Department of Medicinal Chemistry, Faculty of Pharmacy, Minia University, Minia 61519, Egypt; (M.R.F.); (T.F.S.A.); (G.E.-D.A.A.-R.)
| | - Mohammed I. A. Hamed
- Department of Organic and Medicinal Chemistry, Faculty of Pharmacy, Fayoum University, Fayoum 63514, Egypt;
| | - Mohamed Badr
- Department of Biochemistry, Faculty of Pharmacy, Menoufia University, Shibin el Kom 32511, Egypt;
| | - Hanin A. Bogari
- Department of Pharmacy Practice, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
| | - Sameh S. Elhady
- Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
| | - Tarek S. Ibrahim
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt
| | - Gamal El-Din A. Abuo-Rahma
- Department of Medicinal Chemistry, Faculty of Pharmacy, Minia University, Minia 61519, Egypt; (M.R.F.); (T.F.S.A.); (G.E.-D.A.A.-R.)
- Department of Pharmaceutical Medicinal Chemistry, Faculty of Pharmacy, Deraya University, New Minia 61111, Egypt
| | - Taha F. S. Ali
- Department of Medicinal Chemistry, Faculty of Pharmacy, Minia University, Minia 61519, Egypt; (M.R.F.); (T.F.S.A.); (G.E.-D.A.A.-R.)
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Wang T, Zhan Q, Peng X, Qiu Z, Zhao T. CCL2 influences the sensitivity of lung cancer A549 cells to docetaxel. Oncol Lett 2018; 16:1267-1274. [PMID: 30061946 PMCID: PMC6063033 DOI: 10.3892/ol.2018.8769] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 03/09/2018] [Indexed: 01/09/2023] Open
Abstract
Lung cancer is one of the most common malignant tumor types globally. Acquisition of chemoresistance in lung cancer cells is the primary cause of chemotherapy failure. Inflammatory chemokine C-C motif chemokine ligand 2 (CCL2) has been reported to be involved in the progression of cancer and drug resistance. However, its function in docetaxel (DTX) resistance of lung cancer remains unclear. In the present study, the mechanism underlying DTX-induced drug resistance was investigated. Reverse transcription-quantitative polymerase chain reaction and western blot analysis revealed that DTX treatment increased the mRNA and protein expression of CCL2 in lung cancer A549 cells. CCL2 was knocked down by small interfering RNA or was overexpressed by recombinant CCL2 lentivirus, and cell viability was determined. An MTT assay indicated that CCL2 downregulation decreased the viability of A549 cells and augmented the DTX-induced cytotoxicity, whereas CCL2 upregulation protected A549 cells from DTX-induced cytotoxicity. Additionally, it was revealed that CCL2 overexpression activated phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling and inhibited apoptosis-associated protein caspase-3 activation and B-cell lymphoma 2 (Bcl-2) phosphorylation at Ser70 induced by DTX, and enhanced DTX-induced Bcl-2-associated death promoter phosphorylation at Ser112. PI3K/AKT inhibitor LY294002 restored DTX-induced caspase-3 activation and Bcl-2 phosphorylation, reversed the effect of CCL2 on the viability of A549 cells and enhanced DTX-induced cytotoxicity. These results demonstrated that chemoresistance may be mediated by cell stress responses involving CCL2 expression, suggesting that CCL2 may be a potential target for enhancing the therapeutic effect of DTX in lung cancer.
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Affiliation(s)
- Ting Wang
- Department of Oncology, The People's Hospital of Nanchang County, Nanchang, Jiangxi 330200, P.R. China
| | - Qingyuan Zhan
- Department of Internal Medicine 2, Tumor Hospital of Jiangxi Province, Nanchang, Jiangxi 330006, P.R. China
| | - Xiaodong Peng
- Department of Oncology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Zhimin Qiu
- Department of Internal Medicine 6, Tumor Hospital of Jiangxi Province, Nanchang, Jiangxi 330006, P.R. China
| | - Tiantian Zhao
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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Bates D, Eastman A. Microtubule destabilising agents: far more than just antimitotic anticancer drugs. Br J Clin Pharmacol 2016; 83:255-268. [PMID: 27620987 DOI: 10.1111/bcp.13126] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 08/11/2016] [Accepted: 09/07/2016] [Indexed: 02/06/2023] Open
Abstract
Vinca alkaloids have been approved as anticancer drugs for more than 50 years. They have been classified as cytotoxic chemotherapy drugs that act during cellular mitosis, enabling them to target fast growing cancer cells. With the evolution of cancer drug development there has been a shift towards new "targeted" therapies to avoid the side effects and general toxicities of "cytotoxic chemotherapies" such as the vinca alkaloids. Due to their original classification, many have overlooked the fact that vinca alkaloids, taxanes and related drugs do have a specific molecular target: tubulin. They continue to be some of the most effective anticancer drugs, perhaps because their actions upon the microtubule network extend far beyond the ability to halt cells in mitosis, and include the induction of apoptosis at all phases of the cell cycle. In this review, we highlight the numerous cellular consequences of disrupting microtubule dynamics, expanding the textbook knowledge of microtubule destabilising agents and providing novel opportunities for their use in cancer therapy.
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Affiliation(s)
- Darcy Bates
- Department of Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Alan Eastman
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
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Song T, Chai G, Liu Y, Yu X, Wang Z, Zhang Z. Bcl-2 phosphorylation confers resistance on chronic lymphocytic leukaemia cells to the BH3 mimetics ABT-737, ABT-263 and ABT-199 by impeding direct binding. Br J Pharmacol 2016; 173:471-83. [PMID: 26493374 PMCID: PMC4728412 DOI: 10.1111/bph.13370] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 10/08/2015] [Accepted: 10/14/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND AND PURPOSE Although the ongoing clinical trials of ABT-263 and ABT-199 in chronic lymphocytic leukaemia (CLL) have indicated that BH3 mimetics hold considerable promise, understanding the mechanism of CLL resistance to BH3 mimetics remains a challenge. EXPERIMENTAL APPROACH The LD50 values of ABT-737, ABT-263 and ABT-199 in a number of primary CLL cells from 40 patients, were determined. The levels of Bcl-2 family proteins, including phosphorylated Bcl-2 (pBcl-2) and their interactions were measured by immunoblotting and co-immunoprecipitation. In vitro binding assays were performed by isothermal titration calorimetry and ELISA. BH3 profiling in isolated mitochondria was analysed. KEY RESULTS The ratio of (Mcl-1 + pBcl-2) to Bcl-2 expression provided the most significant predictive marker for the cytotoxic potential of ABT-737, ABT-263 and ABT-199 in the panel of CLL samples. Mechanistically, pBcl-2 inhibited the effects of the ABT compounds on the displacement of Bax and Bim from Bcl-2, thereby suppressing mitochondrial apoptosis. The ABT compounds exhibited 100-300-fold lower binding affinity to the glutamic acid, phosphomimetic, mutant of Bcl-2 (T69E, S70E and S87E; EEE-Bcl-2). BH3 peptides exhibited different rank orders of binding affinities to full-length WT-Bcl-2 and full-length EEE-Bcl-2. CONCLUSIONS AND IMPLICATIONS Our study suggested that a structural alteration in the BH3-binding groove was induced by phosphorylation of Bcl-2. Our data also provided a framework to overcome resistance of CLL cells to the ABT compounds by combining pBcl-2 kinase inhibitors with the ABT compounds.
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Affiliation(s)
- Ting Song
- State Key Laboratory of Fine Chemicals, School of ChemistryDalian University of TechnologyDalianChina
| | - Gaobo Chai
- School of Life Science and TechnologyDalian University of TechnologyDalianChina
| | - Yubo Liu
- School of Life Science and TechnologyDalian University of TechnologyDalianChina
| | - Xiaoyan Yu
- School of Life Science and TechnologyDalian University of TechnologyDalianChina
| | - Ziqian Wang
- State Key Laboratory of Fine Chemicals, School of ChemistryDalian University of TechnologyDalianChina
| | - Zhichao Zhang
- State Key Laboratory of Fine Chemicals, School of ChemistryDalian University of TechnologyDalianChina
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Naseri MH, Mahdavi M, Davoodi J, Tackallou SH, Goudarzvand M, Neishabouri SH. Up regulation of Bax and down regulation of Bcl2 during 3-NC mediated apoptosis in human cancer cells. Cancer Cell Int 2015; 15:55. [PMID: 26074734 PMCID: PMC4464715 DOI: 10.1186/s12935-015-0204-2] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 05/11/2015] [Indexed: 01/04/2023] Open
Abstract
Background Recently, we have reported the induction of apoptosis by 2-amino-4-(3-nitrophenyl)-3-cyano-7-(dimethylamino)-4H-chromene (3-NC) in HepG2, T47D and HCT116 cells with low nano molar IC50 values. In this study, anti-proliferative effects of modified 4-aryle-4H-chromenes derivatives; 2-amino-4-(3-bromophenyl)-3-cyano-7-(dimethylamino)-4H-chromene (3-BC), 2-amino-4-(3-trifluoromethylphenyl)-3-cyano-7-(dimethylamino)-4H-chromene (3-TFC) and 2-amino-4-(4,5-methylenedioxyphenyl)-3-cyano-7-(dimethylamino)-4H-chromene (4, 5-MC) were investigated in three human cancer cell lines. Compared to 3-NC none of the compounds displayed better anti-proliferative effect, although 3-BC appeared somewhat similar. Therefore 3-NC was selected for further studies. Methods and results Treatment of HepG2, T47D and HCT116 cells with this compound induced apoptosis as visualized by fluorescence microscopic study of Hoechst 33258 stained cells. Induction of apoptosis was quantified by Annexin V/PI staining using flow cytometry. Western blot analysis also revealed that 3-NC down-regulated the expression of anti-apoptotic protein Bcl2 and up-regulated pro-apoptotic protein Bax, in all of the cell lines. Nonetheless, HepG2 cell line was the most responsive to 3-NC as Bax and Bcl2 showed the most dramatic up and down regulation. Conclusion Our previous finding that 3-NC down regulates Inhibitor of Apoptosis Proteins (IAPs) and the present observation that Bax is upregulated and Bcl2 is down regulated upon 3-NC treatment, this chromene derivative has the potential to overcome chemotherapy resistance caused by up regulation of these proteins.
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Affiliation(s)
- Mohammad Hassan Naseri
- Alborz University of Medical Sciences, Karaj, Iran ; Baqiyatallah University of Medical Sciences (BMSU), Tehran, Iran
| | - Majid Mahdavi
- Department of Biology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran
| | - Jamshid Davoodi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
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Choi BH, Chattopadhaya S, Thanh LN, Feng L, Nguyen QT, Lim CB, Harikishore A, Nanga RPR, Bharatham N, Zhao Y, Liu X, Yoon HS. Suprafenacine, an indazole-hydrazide agent, targets cancer cells through microtubule destabilization. PLoS One 2014; 9:e110955. [PMID: 25354194 PMCID: PMC4212991 DOI: 10.1371/journal.pone.0110955] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 09/26/2014] [Indexed: 12/11/2022] Open
Abstract
Microtubules are a highly validated target in cancer therapy. However, the clinical development of tubulin binding agents (TBA) has been hampered by toxicity and chemoresistance issues and has necessitated the search for new TBAs. Here, we report the identification of a novel cell permeable, tubulin-destabilizing molecule - 4,5,6,7-tetrahydro-1H-indazole-3-carboxylic acid [1p-tolyl-meth-(E)-ylidene]-hydrazide (termed as Suprafenacine, SRF). SRF, identified by in silico screening of annotated chemical libraries, was shown to bind microtubules at the colchicine-binding site and inhibit polymerization. This led to G2/M cell cycle arrest and cell death via a mitochondria-mediated apoptotic pathway. Cell death was preceded by loss of mitochondrial membrane potential, JNK - mediated phosphorylation of Bcl-2 and Bad, and activation of caspase-3. Intriguingly, SRF was found to selectively inhibit cancer cell proliferation and was effective against drug-resistant cancer cells by virtue of its ability to bypass the multidrug resistance transporter P-glycoprotein. Taken together, our results suggest that SRF has potential as a chemotherapeutic agent for cancer treatment and provides an alternate scaffold for the development of improved anti-cancer agents.
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Affiliation(s)
- Bo-Hwa Choi
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Souvik Chattopadhaya
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Le Nguyen Thanh
- Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Lin Feng
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Quoc Toan Nguyen
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Chuan Bian Lim
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Amaravadhi Harikishore
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Ravi Prakash Reddy Nanga
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Nagakumar Bharatham
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Yan Zhao
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Xuewei Liu
- Division of Chemistry and Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Ho Sup Yoon
- Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Department of Genetic Engineering, College of Life Sciences, Kyung Hee University, Yongin-si, Gyeonggi-do, Republic of Korea
- * E-mail:
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Wang J, Beauchemin M, Bertrand R. Phospho-Bcl-xL(Ser62) influences spindle assembly and chromosome segregation during mitosis. Cell Cycle 2014; 13:1313-26. [PMID: 24621501 PMCID: PMC4014433 DOI: 10.4161/cc.28293] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 02/13/2014] [Accepted: 02/19/2014] [Indexed: 01/16/2023] Open
Abstract
Functional analysis of a series of phosphorylation mutants reveals that Bcl-xL(Ser62Ala) influences cell entry into anaphase and mitotic exit in taxol-exposed cells compared with cells expressing wild-type Bcl-xL or a series of other phosphorylation mutants, an effect that appears to be independent of its anti-apoptotic activity. During normal mitosis progression, Bcl-xL(Ser62) is strongly phosphorylated by PLK1 and MAPK14/SAPKp38α at the prometaphase, metaphase, and the anaphase boundaries, while it is de-phosphorylated at telophase and cytokinesis. Phospho-Bcl-xL(Ser62) localizes in centrosomes with γ-tubulin and in the mitotic cytosol with some spindle-assembly checkpoint signaling components, including PLK1, BubR1, and Mad2. In taxol- and nocodazole-exposed cells, phospho-Bcl-xL(Ser62) also binds to Cdc20- Mad2-, BubR1-, and Bub3-bound complexes, while Bcl-xL(Ser62Ala) does not. Silencing Bcl-xL expression and expressing the phosphorylation mutant Bcl-xL(Ser62Ala) lead to an increased number of cells harboring mitotic spindle defects including multipolar spindle, chromosome lagging and bridging, aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h. Together, the data indicate that during mitosis, Bcl-xL(Ser62) phosphorylation impacts on spindle assembly and chromosome segregation, influencing chromosome stability. Observations of mitotic cells harboring aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h were also made with cells expressing the phosphorylation mutant Bcl-xL(Ser49Ala) and dual mutant Bcl-xL(Ser49/62Ala).
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Affiliation(s)
- Jianfang Wang
- Centre de recherche; Centre hospitalier de l’Université de Montréal (CRCHUM) and Institut du Cancer de Montréal; Montréal, Québec, Canada
| | - Myriam Beauchemin
- Centre de recherche; Centre hospitalier de l’Université de Montréal (CRCHUM) and Institut du Cancer de Montréal; Montréal, Québec, Canada
| | - Richard Bertrand
- Centre de recherche; Centre hospitalier de l’Université de Montréal (CRCHUM) and Institut du Cancer de Montréal; Montréal, Québec, Canada
- Département de médecine; Université de Montréal; Montréal, Québec, Canada
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Choi BH, Chakraborty G, Baek K, Yoon HS. Aspirin-induced Bcl-2 translocation and its phosphorylation in the nucleus trigger apoptosis in breast cancer cells. Exp Mol Med 2013; 45:e47. [PMID: 24113271 PMCID: PMC3809363 DOI: 10.1038/emm.2013.91] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 05/14/2013] [Accepted: 06/24/2013] [Indexed: 12/21/2022] Open
Abstract
Here, we report that B-cell lymphoma 2 (Bcl-2) is a novel target molecule of aspirin in breast cancer cells. Aspirin influenced the formation of a complex by Bcl-2 and FKBP38 and induced the nuclear translocation of Bcl-2 and its phosphorylation. These events inhibited cancer cell proliferation and subsequently enhanced MCF-7 breast cancer cell apoptosis. Bcl-2 knockdown using small interfering RNA (siRNA) delayed apoptotic cell death, which correlated with increased proliferation following aspirin exposure. In contrast, Bcl-2 overexpression enhanced the onset of aspirin-induced apoptosis, which was also associated with a significant increase in Bcl-2 phosphorylation in the nucleus. Therefore, this study may provide novel insight into the molecular mechanism of aspirin, particularly its anticancer effects in Bcl-2- and estrogen receptor-positive breast cancer cells.
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Affiliation(s)
- Bo-Hwa Choi
- 1] School of Biological Science, Nanyang Technological University, Singapore, Singapore [2] Pohang Center for Evaluation of Biomaterials, Pohang Technopark, Pohang, South Korea
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Geng F, Tang L, Li Y, Yang L, Choi KS, Kazim AL, Zhang Y. Allyl isothiocyanate arrests cancer cells in mitosis, and mitotic arrest in turn leads to apoptosis via Bcl-2 protein phosphorylation. J Biol Chem 2011; 286:32259-67. [PMID: 21778226 DOI: 10.1074/jbc.m111.278127] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Allyl isothiocyanate (AITC) occurs in many commonly consumed cruciferous vegetables and exhibits significant anti-cancer activities. Available data suggest that it is particularly promising for bladder cancer prevention and/or treatment. Here, we show that AITC arrests human bladder cancer cells in mitosis and also induces apoptosis. Mitotic arrest by AITC was associated with increased ubiquitination and degradation of α- and β-tubulin. AITC directly binds to multiple cysteine residues of the tubulins. AITC induced mitochondrion-mediated apoptosis, as shown by cytochrome c release from mitochondria to cytoplasm, activation of caspase-9 and caspase-3, and formation of TUNEL-positive cells. Inhibition of caspase-9 blocked AITC-induced apoptosis. Moreover, we found that apoptosis induction by AITC depended entirely on mitotic arrest and was mediated via Bcl-2 phosphorylation at Ser-70. Pre-arresting cells in G(1) phase by hydroxyurea abrogated both AITC-induced mitotic arrest and Bcl-2 phosphorylation. Overexpression of a Bcl-2 mutant prevented AITC from inducing apoptosis. We further showed that AITC-induced Bcl-2 phosphorylation was caused by c-Jun N-terminal kinase (JNK), and AITC activates JNK. Taken together, this study has revealed a novel anticancer mechanism of a phytochemical that is commonly present in human diet.
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Affiliation(s)
- Feng Geng
- Department of Cancer Prevention and Control, California Institute of Technology, Pasadena, California 91125, USA
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Geng H, Rademacher BL, Pittsenbarger J, Huang CY, Harvey CT, Lafortune MC, Myrthue A, Garzotto M, Nelson PS, Beer TM, Qian DZ. ID1 enhances docetaxel cytotoxicity in prostate cancer cells through inhibition of p21. Cancer Res 2010; 70:3239-48. [PMID: 20388787 DOI: 10.1158/0008-5472.can-09-3186] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
To identify potential mechanisms underlying prostate cancer chemotherapy response and resistance, we compared the gene expression profiles in high-risk human prostate cancer specimens before and after neoadjuvant chemotherapy and radical prostatectomy. Among the molecular signatures associated with chemotherapy, transcripts encoding inhibitor of DNA binding 1 (ID1) were significantly upregulated. The patient biochemical relapse status was monitored in a long-term follow-up. Patients with ID1 upregulation were found to be associated with longer relapse-free survival than patients without ID1 increase. This in vivo clinical association was mechanistically investigated. The chemotherapy-induced ID1 upregulation was recapitulated in the prostate cancer cell line LNCaP. Docetaxel dose-dependently induced ID1 transcription, which was mediated by ID1 promoter E-box chromatin modification and c-Myc binding. Stable ID1 overexpression in LNCaP increased cell proliferation, promoted G(1) cell cycle progression, and enhanced docetaxel-induced cytotoxicity. These changes were accompanied by a decrease in cellular mitochondria content, an increase in BCL2 phosphorylation at serine 70, caspase-3 activation, and poly(ADP-ribose) polymerase cleavage. In contrast, ID1 siRNA in the LNCaP and C42B cell lines reduced cell proliferation and decreased docetaxel-induced cytotoxicity by inhibiting cell death. ID1-mediated chemosensitivity enhancement was in part due to ID1 suppression of p21. Overexpression of p21 in LNCaP-ID1-overexpressing cells restored the p21 level and reversed ID1-enhanced chemosensitivity. These molecular data provide a mechanistic rationale for the observed in vivo clinical association between ID1 upregulation and relapse-free survival. Taken together, it shows that ID1 expression has a novel therapeutic role in prostate cancer chemotherapy and prognosis.
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Affiliation(s)
- Hao Geng
- Division of Hematology and Medical Oncology, Oregon Health & Science University, Portland, Oregon 97239, USA
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Qian DZ, Rademacher BL, Pittsenbarger J, Huang CY, Myrthue A, Higano CS, Garzotto M, Nelson PS, Beer TM. CCL2 is induced by chemotherapy and protects prostate cancer cells from docetaxel-induced cytotoxicity. Prostate 2010; 70:433-42. [PMID: 19866475 PMCID: PMC2931415 DOI: 10.1002/pros.21077] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Metastatic prostate cancer is either inherently resistant to chemotherapy or rapidly acquires this phenotype after chemotherapy exposure. In this study, we identified a docetaxel-induced resistance mechanism centered on CCL2. METHODS We compared the gene expression profiles in individual human prostate cancer specimens before and after exposure to chemotherapy collected from previously untreated patients who participated in a clinical trial of preoperative chemotherapy. Subsequently, we used the gain- and loss-of-function approach in vitro to identify a potential mechanism underlying chemotherapy resistance. RESULTS Among the molecular signatures associated with treatment, several genes that regulate the inflammatory response and chemokine activity were upregulated including a significant increase in transcripts encoding the CC chemokine CCL2. Docetaxel increased CCL2 expression in prostate cancer cell lines in vitro. CCL2-specific siRNA inhibited LNCaP and LAPC4 cell proliferation and enhanced the growth inhibitory effect of low-dose docetaxel. In contrast, overexpression of CCL2 or recombinant CCL2 protein stimulated prostate cancer cell proliferation and rescued cells from docetaxel-induced cytotoxicity. This protective effect of CCL2 was associated with activation of the ERK/MAP kinase and PI3K/AKT, inhibition of docetaxel-induced Bcl2 phosphorylation at serine 70, phosphorylation of Bad, and activation of caspase-3. The addition of a PI3K/AKT inhibitor Ly294002 reversed the CCL2 protection and was additive to docetaxel-induced toxicity. CONCLUSION These results support a mechanism of chemotherapy resistance mediated by cellular stress responses involving the induction of CCL2 expression and suggest that inhibiting CCL2 activity could enhance therapeutic responses to taxane-based therapy.
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Affiliation(s)
- David Z. Qian
- Division of Hematology and Medical Oncology, Oregon Health & Science University, Portland, OR
| | - Brooks L.S. Rademacher
- Division of Hematology and Medical Oncology, Oregon Health & Science University, Portland, OR
| | - Janet Pittsenbarger
- Division of Hematology and Medical Oncology, Oregon Health & Science University, Portland, OR
| | - Chung-Ying Huang
- Divisions of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Anne Myrthue
- Division of Hematology and Medical Oncology, Oregon Health & Science University, Portland, OR
| | | | - Mark Garzotto
- Division of Urology, Oregon Health & Science University and Portland VA Medical Center, Portland, OR, USA
| | - Peter S. Nelson
- Divisions of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA
- Division of Medical Oncology, University of Washington, Seattle, WA
| | - Tomasz M. Beer
- Division of Hematology and Medical Oncology, Oregon Health & Science University, Portland, OR
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Aquilano K, Vigilanza P, Filomeni G, Rotilio G, Ciriolo MR. Tau dephosphorylation and microfilaments disruption are upstream events of the anti-proliferative effects of DADS in SH-SY5Y cells. J Cell Mol Med 2008; 14:564-77. [PMID: 19040422 PMCID: PMC3823456 DOI: 10.1111/j.1582-4934.2008.00588.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Garlic organosulphur compounds have been successfully used as redox anti-proliferative agents. In this work, we dissect the effects of diallyl disulphide (DADS) focusing on the events upstream of cell cycle arrest and apoptosis induced in neuroblastoma SH-SY5Y cells. We demonstrate that DADS is able to cause early morphological changes, cytoskeleton oxidation, microfilaments reduction and depolymerization of microtubules. These events are attenuated in cells stably overexpressing the antioxidant enzyme SOD1, suggesting that superoxide plays a crucial role in destabilizing cytoskeleton. Moreover, we evidence that the main microtubules-associated protein Tau undergoes PP1-mediated dephosphorylation as demonstrated by treatment with okadaic acid as well as by immunoreaction with anti-Tau-1 antibody, which specifically recognizes its dephosphorylated forms. Tau dephosphorylation is inhibited by the two-electron reductants NAC and GSH ester but not by SOD1. The inability of DADS to induce apoptosis in neuroblastoma-differentiated cells gives emphasis to the anti-proliferative activity of DADS, which can be regarded as a promising potent anti-neuroblastoma drug by virtue of its widespread cytoskeleton disrupting action on proliferating cells.
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Affiliation(s)
- Katia Aquilano
- Department of Biology, University of Rome Tor Vergata, Via della Ricerca Scientifica, 00133, Rome, Italy
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13
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McCubrey JA, Steelman LS, Chappell WH, Abrams SL, Wong EWT, Chang F, Lehmann B, Terrian DM, Milella M, Tafuri A, Stivala F, Libra M, Basecke J, Evangelisti C, Martelli AM, Franklin RA. Roles of the Raf/MEK/ERK pathway in cell growth, malignant transformation and drug resistance. BIOCHIMICA ET BIOPHYSICA ACTA 2007; 1773:1263-84. [PMID: 17126425 PMCID: PMC2696318 DOI: 10.1016/j.bbamcr.2006.10.001] [Citation(s) in RCA: 1669] [Impact Index Per Article: 98.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Revised: 10/02/2006] [Accepted: 10/03/2006] [Indexed: 02/07/2023]
Abstract
Growth factors and mitogens use the Ras/Raf/MEK/ERK signaling cascade to transmit signals from their receptors to regulate gene expression and prevent apoptosis. Some components of these pathways are mutated or aberrantly expressed in human cancer (e.g., Ras, B-Raf). Mutations also occur at genes encoding upstream receptors (e.g., EGFR and Flt-3) and chimeric chromosomal translocations (e.g., BCR-ABL) which transmit their signals through these cascades. Even in the absence of obvious genetic mutations, this pathway has been reported to be activated in over 50% of acute myelogenous leukemia and acute lymphocytic leukemia and is also frequently activated in other cancer types (e.g., breast and prostate cancers). Importantly, this increased expression is associated with a poor prognosis. The Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt pathways interact with each other to regulate growth and in some cases tumorigenesis. For example, in some cells, PTEN mutation may contribute to suppression of the Raf/MEK/ERK cascade due to the ability of activated Akt to phosphorylate and inactivate different Rafs. Although both of these pathways are commonly thought to have anti-apoptotic and drug resistance effects on cells, they display different cell lineage specific effects. For example, Raf/MEK/ERK is usually associated with proliferation and drug resistance of hematopoietic cells, while activation of the Raf/MEK/ERK cascade is suppressed in some prostate cancer cell lines which have mutations at PTEN and express high levels of activated Akt. Furthermore the Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt pathways also interact with the p53 pathway. Some of these interactions can result in controlling the activity and subcellular localization of Bim, Bak, Bax, Puma and Noxa. Raf/MEK/ERK may promote cell cycle arrest in prostate cells and this may be regulated by p53 as restoration of wild-type p53 in p53 deficient prostate cancer cells results in their enhanced sensitivity to chemotherapeutic drugs and increased expression of Raf/MEK/ERK pathway. Thus in advanced prostate cancer, it may be advantageous to induce Raf/MEK/ERK expression to promote cell cycle arrest, while in hematopoietic cancers it may be beneficial to inhibit Raf/MEK/ERK induced proliferation and drug resistance. Thus the Raf/MEK/ERK pathway has different effects on growth, prevention of apoptosis, cell cycle arrest and induction of drug resistance in cells of various lineages which may be due to the presence of functional p53 and PTEN and the expression of lineage specific factors.
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Affiliation(s)
- James A McCubrey
- Department of Microbiology and Immunology, Leo Jenkins Cancer Center, Brody School of Medicine at East Carolina University, Greenville, NC 27858, USA.
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14
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Gururaja TL, Goff D, Kinoshita T, Goldstein E, Yung S, McLaughlin J, Pali E, Huang J, Singh R, Daniel-Issakani S, Hitoshi Y, Cooper RDG, Payan DG. R-253 disrupts microtubule networks in multiple tumor cell lines. Clin Cancer Res 2006; 12:3831-42. [PMID: 16778111 DOI: 10.1158/1078-0432.ccr-06-0168] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The design and development of synthetic small molecules to disrupt microtubule dynamics is an attractive therapeutic strategy for anticancer drug discovery research. Loss of clinical efficacy of many useful drugs due to drug resistance in tumor cells seems to be a major hurdle in this endeavor. Thus, a search for new chemical entities that bind tubulin, but neither are a substrate of efflux pump, P-glycoprotein 170/MDR1, nor cause undesired side effects, would potentially increase the therapeutic index in certain cancer treatments. EXPERIMENTAL DESIGN A high-content cell-based screen of a compound library led to the identification of a new class of compounds belonging to a thienopyrimidine series, which exhibited significant antitumor activities. On structure-activity relationship analysis, R-253 [N-cyclopropyl-2-(6-(3,5-dimethylphenyl)thieno[3,2-d]pyrimidin-4-yl)hydrazine carbothioamide] emerged as a potent antiproliferative agent (average EC(50), 20 nmol/L) when examined in a spectrum of tumor cell lines. RESULTS R-253 is structurally unique and destabilizes microtubules both in vivo and in vitro. Standard fluorescence-activated cell sorting and Western analyses revealed that the effect of R-253 on cell growth was associated with cell cycle arrest in mitosis, increased select G(2)-M checkpoint proteins, and apoptosis. On-target activity of R-253 on microtubules was further substantiated by immunofluorescence studies and selected counter assays. R-253 competed with fluorescent-labeled colchicine for binding to tubulin, indicating that its binding site on tubulin could be similar to that of colchicine. R-253 neither is a substrate of P-glycoprotein 170/MDR1 nor is cytotoxic to nondividing human hepatocytes. CONCLUSION Both biochemical and cellular mechanistic studies indicate that R-253 could become a promising new tubulin-binding drug candidate for treating various malignancies.
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Tang Y, Khan MA, Goloubeva O, Lee DI, Jelovac D, Brodie AM, Hussain A. Docetaxel followed by castration improves outcomes in LNCaP prostate cancer-bearing severe combined immunodeficient mice. Clin Cancer Res 2006; 12:169-74. [PMID: 16397039 DOI: 10.1158/1078-0432.ccr-05-1388] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Androgen ablation is the standard initial treatment for advanced prostate cancer; however, tumors eventually develop androgen independence and become incurable. Chemotherapy is commonly used after hormone treatment fails but has not shown significant survival benefit. Studies suggest that androgen ablation can select for a population of hormone-independent cells that are also relatively chemotherapy resistant. Thus, it may be therapeutically advantageous to target prostate cancer with chemotherapy before hormone ablation. This study was undertaken to determine the relative efficacy of such an approach in a preclinical model of prostate cancer. EXPERIMENTAL DESIGN Severe combined immunodeficient mice bearing human LNCaP prostate tumors were treated with docetaxel and/or surgical castration applied singly, concurrently, or in different sequences. Treatment efficacy was determined by tumor volume and growth delay measurements. The extent of apoptosis in tumors in response to treatments was assessed via terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assays. In addition, Western blots were done to study the relative expression of Bcl-2 and Bax in the tumors. RESULTS Docetaxel followed by castration showed the most potent antitumor effects. In contrast, with the exception of castration alone, castration followed by docetaxel produced the least antitumor activity. TUNEL assays confirmed that the density of apoptotic tumor cells was significantly greater for docetaxel followed by castration than for any other treatment. In tumors of mice treated with single modality therapies, Bax to Bcl-2 ratios decreased significantly after castration, whereas this ratio remained high after docetaxel treatment. CONCLUSION A treatment sequence of docetaxel followed by hormone ablation may be more effective in treating prostate cancer than concurrent docetaxel/hormone therapy or hormone ablation followed by docetaxel.
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Affiliation(s)
- Yao Tang
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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16
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Kondo E, Miyake T, Shibata M, Kimura T, Iwagaki H, Nakamura SI, Tanaka T, Ohara N, Ichimura K, Oka T, Yanai H, Shibasaki F, Yoshino T. Expression of Phosphorylated Ser70of Bcl-2 Correlates with Malignancy in Human Colorectal Neoplasms. Clin Cancer Res 2005; 11:7255-63. [PMID: 16243795 DOI: 10.1158/1078-0432.ccr-05-0274] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Bcl-2 is a model apoptosis suppressor postulated to promote tumorigenesis. Recently, it has been reported that Bcl-2 undergoes phosphoregulation of its Ser70 to substantially alter its molecular function. Previous studies further suggest that such phospho-Bcl-2 regulation may influence tumor progression in colorectal and other cancers; however, phosphorylation status of the Ser70 of Bcl-2 (pSer70) in vivo in tumors remains obscure. To elucidate this question that may suggest the biological role, we molecularly screened a panel of human colorectal adenomas and adenocarcinomas for endogenous expression of pSer70 Bcl-2. EXPERIMENTAL DESIGN An antibody specific against pSer70 Bcl-2 was generated for thorough immunohistochemical examination of paraffin-embedded tumor specimens, allowing detection of the endogenously expressed antigen among a range of Bcl-2-positive colorectal neoplasms, including 75 tubular adenomas, 114 adenocarcinomas, and 15 cases of cancer in adenomas. RESULTS Loss of pSer70 Bcl-2 expression was observed in adenocarcinomas in a differentiation-dependent manner (positivities: well differentiated 63%, moderately differentiated 52%, and poorly differentiated 12%), whereas tubular adenomas maintained their expression (positivity 88%). Interestingly, an inverse correlation was found between expression of pSer70 Bcl-2 and Ki-67 antigen in those cases of cancer in adenoma (P < 0.01). It was further observed that loss of pSer70 Bcl-2 expression was associated with significantly shorter survival (P < 0.05) and correlated with clinical stages and lymph node metastasis (P < 0.05 and P < 0.05, respectively). CONCLUSIONS Loss of pSer70 Bcl-2 expression is closely linked to biological aggressiveness in colorectal tumors and represents a statistically significant molecular index for prognosis of patients with these tumors.
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Affiliation(s)
- Eisaku Kondo
- Department of Pathology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan.
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Teraishi F, Wu S, Sasaki J, Zhang L, Davis JJ, Guo W, Dong F, Fang B. JNK1-dependent antimitotic activity of thiazolidin compounds in human non-small-cell lung and colon cancer cells. Cell Mol Life Sci 2005; 62:2382-9. [PMID: 16179969 PMCID: PMC1351099 DOI: 10.1007/s00018-005-5365-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We recently identified two thiazolidin compounds, 5-[(4-methylphenyl)methylene]-2-(phenylamino)-4(5H)-thiazolone (MMPT) and 5-(2,4-dihydroxybenzylidene)-2-(phenylimino)-1,3-thiazolidin (DBPT), that inhibit the growth of human non-small-cell lung and colon cancer cells independent of P-glycoprotein and p53 status. Here we further investigated the mechanism by which these thiazolidin compounds mediate their anticancer effects. Treatment of cancer cells with MMPT and DBPT led to a time-dependent accumulation of cells arrested in the G2/M phase with modulation of the expression of proteins such as cyclin B1, cdc25C, and phosphorylated histone H3. Moreover, treatment with MMPT and DBPT increased M-phase arrest with abnormal spindle formation. DBPT-mediated G2/M phase arrest and phosphorylation of cdc25C and histone H3 were abrogated when JNK activation was blocked either with SP600125, a specific JNK inhibitor, or a dominant-negative JNK1 gene. Moreover, DBPT-mediated microtubule disruption was also blocked by SP600125 treatment. Our results demonstrate that thiazolidin compounds can effectively induce G2/M arrest in cancer cells and that this G2/M arrest requires JNK activation.
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Affiliation(s)
- F. Teraishi
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - S. Wu
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - J. Sasaki
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - L. Zhang
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - J. J. Davis
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - W. Guo
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - F. Dong
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
| | - B. Fang
- Department of Thoracic and Cardiovascular Surgery, Unit 445, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, Texas 77030 (USA), FAX: +1713 794 4901, e-mail:
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Kasibhatla S, Gourdeau H, Meerovitch K, Drewe J, Reddy S, Qiu L, Zhang H, Bergeron F, Bouffard D, Yang Q, Herich J, Lamothe S, Cai SX, Tseng B. Discovery and mechanism of action of a novel series of apoptosis inducers with potential vascular targeting activity. Mol Cancer Ther 2004. [DOI: 10.1158/1535-7163.1365.3.11] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
A novel series of 2-amino-4-(3-bromo-4,5-dimethoxy-phenyl)-3-cyano-4H-chromenes was identified as apoptosis-inducing agents through our cell-based apoptosis screening assay. Several analogues from this series, MX-58151, MX-58276, MX-76747, MX-116214, MX-126303, and MX-116407, were synthesized and further characterized. MX-116407, a lead compound from this series, induced apoptosis with an EC50 of 50 nmol/L and inhibited cell growth with a GI50 of 37 nmol/L in T47D breast cancer cells. Treatment of cells with these analogues led to G2-M arrest, cleavage of essential proapoptotic caspase substrates, and induction of nuclear fragmentation. We identified these compounds as tubulin destabilizers with binding site at or close to the colchicine binding site. Compounds in this series were also active in drug-resistant cancer cell lines with a GI50 value for one of the analogues (MX-58151) of 2.5 nmol/L in paclitaxel-resistant, multidrug-resistant MES-SA/DX5 tumor cells. This series of compounds displayed high selectivity against proliferating versus resting cells. Interestingly, these compounds were shown to disrupt preformed endothelial cell capillary tubules in vitro and affect functional vasculature to induce tumor necrosis in vivo and are thus likely to work as tumor vasculature targeting agents. Among these compounds, MX-116407 showed capillary tubule disruption activity in vitro at concentrations well below the cytotoxic dose. In a separate study, we further characterized the antitumor efficacy and pharmacokinetic profile of this series of compounds and identified MX-116407 as a potent apoptosis-inducing agent with apparent activity as tumor vasculature targeting agent.
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Affiliation(s)
| | | | | | - John Drewe
- 1Maxim Pharmaceuticals, Inc., San Diego, California and
| | | | - Ling Qiu
- 1Maxim Pharmaceuticals, Inc., San Diego, California and
| | - Hong Zhang
- 1Maxim Pharmaceuticals, Inc., San Diego, California and
| | | | | | - Quan Yang
- 2Shire BioChem, Inc., Laval, Quebec, Canada
| | - John Herich
- 1Maxim Pharmaceuticals, Inc., San Diego, California and
| | | | - Sui Xiong Cai
- 1Maxim Pharmaceuticals, Inc., San Diego, California and
| | - Ben Tseng
- 1Maxim Pharmaceuticals, Inc., San Diego, California and
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19
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Masuda A, Maeno K, Nakagawa T, Saito H, Takahashi T. Association between mitotic spindle checkpoint impairment and susceptibility to the induction of apoptosis by anti-microtubule agents in human lung cancers. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 163:1109-16. [PMID: 12937152 PMCID: PMC1868274 DOI: 10.1016/s0002-9440(10)63470-0] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Anti-microtubule agents such as vinorelbine and paclitaxel, which are extensively used in the treatment of lung cancers, activate mitotic spindle checkpoint. Although defects of the mitotic spindle checkpoint are thought to play a role in the genesis of chromosome instability, we previously reported its frequent impairment in human lung cancer cell lines. In this study, we examined a panel of 13 human cancer cell lines comprising 11 lung and 2 other cancers and found a significant difference in the resistance to apoptosis induced by anti-microtubule agents between mitotic spindle checkpoint-impaired and -proficient cancer cell lines. This finding was in marked contrast to a lack of such correlation with a DNA damaging agent, cis-platin. Interestingly, anti-microtubule agent-induced apoptosis in mitotic spindle checkpoint-proficient cell lines, NCI-H460 and A549, was shown to be markedly reduced by staurosporine treatment in association with the shortened mitotic arrest, whereas various inhibitors of caspases seemed to have very modest effects. Taken together, these findings suggest the potential involvement of mitotic spindle checkpoint in the induction of apoptosis by anti-microtubule agents in human lung cancers, warranting further studies on the underlying mechanisms.
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Affiliation(s)
- Akira Masuda
- Division of Molecular Oncology, Aichi Cancer Center Research Institute, 1-1 Kanoko-den, Chikusa-ku, Nagoya 464-8681, Japan
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20
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Basu A, Das M, Qanungo S, Fan XJ, DuBois G, Haldar S. Proteasomal degradation of human peptidyl prolyl isomerase pin1-pointing phospho Bcl2 toward dephosphorylation. Neoplasia 2002; 4:218-27. [PMID: 11988841 PMCID: PMC1531695 DOI: 10.1038/sj.neo.7900233] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2001] [Accepted: 12/17/2001] [Indexed: 11/09/2022]
Abstract
Microtubule inhibitor-induced Bcl2 phosphorylation is detrimental to its antiapoptotic function. Phosphorylation of Bcl2 predominantly occurs on two serine residues (70 and 87) in cells arrested at G2-M phase by microtubule disarraying agents. Phospho Bcl2 can associate with a cis-trans peptidyl prolyl isomerase, Pin1. Pin1 and its homologues are known to target the proline residue carboxyl terminal to the phosphorylated threonine or serine residue of mitotic phosphoproteins, such as Bcl2. However, it was not clear how an extranuclear protein could associate with nuclear Pin1. The confocal images of the immunofluorescence studies employing phospho Bcl2-specific antibody developed in the laboratory demonstrated the translocation of phospho Bcl2 inside the nucleus. Interestingly, proteasomal degradation of Pin1 facilitates dephosphorylation of phospho Bcl2 due to longer exposure of Taxol. Here we show for the first time that proteasomal degradation of Pin1 is the key factor to determine the fate of phosphoforms of Bcl2. When Pin1 is degraded by proteasomes, phospho Bcl2 is converted to its native form. Thus, transient conformational change of Bcl2 due to association with peptidyl prolyl isomerase can contribute to irreversible apoptotic signaling.
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Affiliation(s)
- Aruna Basu
- Department of Research, Pharmacology, Ireland Cancer Center, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
| | - Madhusudan Das
- Department of Research, Pharmacology, Ireland Cancer Center, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
| | - Suparna Qanungo
- Department of Research, Pharmacology, Ireland Cancer Center, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
| | - Xue-Jun Fan
- Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Garrett DuBois
- Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Subrata Haldar
- Department of Research, Pharmacology, Ireland Cancer Center, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
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Kruczynski A, Etiévant C, Perrin D, Chansard N, Duflos A, Hill BT. Characterization of cell death induced by vinflunine, the most recent Vinca alkaloid in clinical development. Br J Cancer 2002; 86:143-50. [PMID: 11857026 PMCID: PMC2746541 DOI: 10.1038/sj.bjc.6600025] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2001] [Revised: 10/10/2001] [Accepted: 10/17/2001] [Indexed: 11/15/2022] Open
Abstract
Vinflunine, the most recent Vinca alkaloid in clinical development, demonstrated superior antitumour activity to other Vincas in preclinical tumour models. This study aimed to define its molecular mechanisms of cell killing in both parental sensitive and vinflunine-resistant P388 leukaemia cells. Vinflunine treatment of these cells resulted in apoptosis characterized by DNA fragmentation and proteolytic cleavage of poly-(ADP-ribose) polymerase. Apoptosis-inducing concentrations of vinflunine caused c-Jun N-terminal kinase 1 stimulation, as well as caspases-3/7 activation. This activation of caspases and the induction of apoptosis could be inhibited by the caspase inhibitor acetyl-Asp-Glu-Val-Asp-aldehyde. Interestingly, the apoptosis signal triggered by vinflunine in these P388 cells was not mediated through Bcl-2 phosphorylation. In addition, when vinflunine resistance was developed in P388 cells, it was associated with resistance to vinflunine-induced apoptosis, as reflected by a loss of capacity to induce DNA fragmentation and PARP degradation, and characterized by increased levels of Bcl-2 and Bfl-1/A1. Therefore, these data indirectly implicate Bcl-2 and Bfl-1/A1 in vinflunine-induced cell death mechanisms.
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Affiliation(s)
- A Kruczynski
- Division of Experimental Cancer Research, Centre de Recherche Pierre Fabre, 17 avenue Jean Moulin, 81106 Castres, Cedex 06, France.
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22
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Pathan N, Aime-Sempe C, Kitada S, Basu A, Haldar S, Reed JC. Microtubule-targeting drugs induce bcl-2 phosphorylation and association with Pin1. Neoplasia 2001; 3:550-9. [PMID: 11774038 PMCID: PMC1506558 DOI: 10.1038/sj.neo.7900213] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2000] [Accepted: 12/18/2000] [Indexed: 12/20/2022] Open
Abstract
Bcl-2 is a critical suppressor of apoptosis that is overproduced in many types of cancer. Phosphorylation of the Bcl-2 protein is induced on serine residues in tumor cells arrested by microtubule-targeting drugs (paclitaxel, vincristine, nocodazole) and has been associated with inactivation of antiapoptotic function through an unknown mechanism. Comparison of a variety of pharmacological inhibitors of serine/threonine-specific protein kinases demonstrated that the cyclin-dependent kinase inhibitor, flavopiridol, selectively blocks Bcl-2 phosphorylation induced by antimicrotubule drugs. Bcl-2 could also be coimmunoprecipitated with the kinase Cdc2 in M-phase-arrested cells, suggesting that Cdc2 may be responsible for phosphorylation of Bcl-2 in cells treated with microtubule-targeting drugs. Examination of several serine-->alanine substitution mutants of Bcl-2 suggested that serine 70 and serine 87 represent major sites of Bcl-2 phosphorylation induced in response to microtubule-targeting drugs. Both these serines are within sequence contexts suitable for proline-directed kinases such as Cdc2. Phosphorylated Bcl-2 protein was discovered to associate in M-phase-arrested cells with Pin1, a mitotic peptidyl prolyl isomerase (PPIase) known to interact with substrates of Cdc2 during mitosis. In contrast, phosphorylation of Bcl-2 induced by microtubule-targeting drugs did not alter its ability to associate with Bcl-2 (homodimerization), Bax, BAG1, or other Bcl-2-binding proteins. Since the region in Bcl-2 containing serine 70 and serine 87 represents a proline-rich loop that has been associated with autorepression of its antiapoptotic activity, the discovery of Pin1 interactions with phosphorylated Bcl-2 raises the possibility that Pin1 alters the conformation of Bcl-2 and thereby modulates its function in cells arrested with antimicrotubule drugs.
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Affiliation(s)
- N Pathan
- The Burnham Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
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23
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Liu XM, Wang LG, Kreis W, Budman DR, Adams LM. Differential effect of vinorelbine versus paclitaxel on ERK2 kinase activity during apoptosis in MCF-7 cells. Br J Cancer 2001; 85:1403-11. [PMID: 11720482 PMCID: PMC2375254 DOI: 10.1054/bjoc.2001.2107] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The effects of vinorelbine and paclitaxel on the activity of extracellular signal-regulated protein kinase2 (ERK2), a member of MAP kinase, and its role in the induction of bcl-2 phosphorylation and apoptosis were evaluated in MCF-7 cells. We demonstrated that ERK2 was activated rapidly by vinorelbine, and was inhibited by either paclitaxel or estramustine. A 3-fold increase of ERK2 kinase activity was observed within 30 min when MCF-7 cells were treated with 0.1 microM vinorelbine. In contrast, the same treatment with paclitaxel resulted in a significant decrease of ERK2 kinase activity. We also demonstrated that elevated bcl-2 phosphorylation induced by vinorelbine is paralleled by decrease of a complex formation between bcl-2 and bax, cleavage of poly (ADP) ribose polymerase (PARP) protein, activation of caspase-7, and apoptosis. The levels of bcl-2 phosphorylation, bax, and PARP were not significantly affected by 2'-amino-3'-methoxyflavone (PD 98059), an ERK kinase specific inhibitor. Thus, our data suggest that the apoptosis induced by vinorelbine in MCF-7 cells is mediated through the bcl-2 phosphorylation/bax/caspases pathways, and that activation of ERK2 by vinorelbine does not directly lead to the drug-mediated apoptosis. Since decrease of PARP occurred quickly following the treatment of MCF-7 cells with either 0.1 microM of vinorelbine or paclitaxel, this protein may serve as an early indicator of apoptosis induced not only by DNA damaging agents, but also by antimicrotubule drugs.
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Affiliation(s)
- X M Liu
- Don Monti Division of Medical Oncology, North Shore University Hospital, NYU School of Medicine, Manhasset, New York 11030, USA
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24
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Abstract
Bcl-2, an antiapoptotic protein, protects cells against many but not all forms of apoptosis. For example, Bcl-2 does not protect non-neuronal cells against taxol, a microtubule-stabilizing agent. The underlying mechanism for the ineffectiveness of Bcl-2 against taxol has been the subject of intense interest. Data from non-neuronal cells indicate that taxol-induced apoptosis requires activation of N-terminal c-Jun protein kinase (JNK) that phosphorylates and inactivates Bcl-2. This suggests the interesting possibility that the apoptotic activity of JNK may be caused by phosphorylation of Bcl-2 and inhibition of the antiapoptotic activity of Bcl-2. Here we report that taxol induces apoptosis in cortical neurons but by a mechanism significantly different from that in non-neuronal cells. In contrast to human embryonic kidney 293 cells, expression of wild-type Bcl-2 in cortical neurons protected against taxol-induced apoptosis, and taxol did not induce Bcl-2 phosphorylation. Furthermore, cortical neurons express high basal JNK activity, and taxol did not stimulate total JNK activity. However, taxol activated a subpool of JNK in the nucleus and stimulated c-Jun phosphorylation. JNK inhibition or expression of a dominant-negative c-Jun abrogated taxol-induced apoptosis in cortical neurons, suggesting a role for JNK and JNK-mediated transcription in taxol-stimulated apoptosis. Furthermore, taxol-induced apoptosis in cortical neurons required inhibition of phosphatidylinositol 3-kinase signaling. These data suggest that taxol induces apoptosis in neurons by a mechanism quite distinct from that of non-neuronal cell lines and emphasize the importance of elucidating apoptotic mechanisms specific for neurons in the CNS.
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Pathan N, Aime-Sempe C, Kitada S, Haldar S, Reed JC. Microtubule-targeting drugs induce Bcl-2 phosphorylation and association with Pin1. Neoplasia 2001; 3:70-9. [PMID: 11326318 PMCID: PMC1505024 DOI: 10.1038/sj.neo.7900131] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2000] [Accepted: 12/13/2000] [Indexed: 11/09/2022] Open
Abstract
Bcl-2 is a critical suppressor of apoptosis that is overproduced in many types of cancer. Phosphorylation of the Bcl-2 protein is induced on serine residues in tumor cells arrested by microtubule-targeting drugs (paclitaxel, vincristine, nocodazole) and has been associated with inactivation of antiapoptotic function through an unknown mechanism. Comparison of a variety of pharmacological inhibitors of serine/threonine-specific protein kinases demonstrated that the cyclin-dependent kinase inhibitor, flavopiridol, selectively blocks Bcl-2 phosphorylation induced by antimicrotubule drugs. Bcl-2 could also be coimmunoprecipitated with the kinase Cdc2 in M-phase-arrested cells, suggesting that a Cdc2 may be responsible for phosphorylation of Bcl-2 in cells treated with microtubule-targeting drugs. Examination of several serine-->alanine substitution mutants of Bcl-2 suggested that serine 70 and serine 87 represent major sites of Bcl-2 phosphorylation induced in response to microtubule-targeting drugs. Both these serines are within sequence contexts suitable for proline-directed kinases such as Cdc2. Phosphorylated Bcl-2 protein was discovered to associate in M-phase-arrested cells with Pin1, a mitotic peptidyl prolyl isomerase (PPIase) known to interact with substrates of Cdc2 during mitosis. In contrast, phosphorylation of Bcl-2 induced by microtubule-targeting drugs did not alter its ability to associate with Bcl-2 (homodimerization), Bax, BAG1, or other Bcl-2-binding proteins. Since the region in Bcl-2 containing serine 70 and serine 87 represents a proline-rich loop that has been associated with autorepression of its antiapoptotic activity, the discovery of Pin1 interactions with phosphorylated Bcl-2 raises the possibility that Pin1 alters the conformation of Bcl-2 and thereby modulates its function in cells arrested with antimicrotubule drugs.
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Affiliation(s)
- N Pathan
- The Burnham Institute, 10901 N. Torrey Pines, La Jolla, CA 92037, USA
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Deng X, Ruvolo P, Carr B, May WS. Survival function of ERK1/2 as IL-3-activated, staurosporine-resistant Bcl2 kinases. Proc Natl Acad Sci U S A 2000; 97:1578-83. [PMID: 10677502 PMCID: PMC26477 DOI: 10.1073/pnas.97.4.1578] [Citation(s) in RCA: 191] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bcl2 phosphorylation at Ser-70 may be required for the full and potent suppression of apoptosis in IL-3-dependent myeloid cells and can result from agonist activation of mitochondrial protein kinase C (PKC). Paradoxically, expression of exogenous Bcl2 can protect parental cells from apoptosis induced by the potent PKC inhibitor, staurosporine (stauro). High concentrations of stauro of up to 1 microM only partially inhibit IL-3-stimulated Bcl2 phosphorylation but completely block PKC-mediated Bcl2 phosphorylation in vitro. These data indicate a role for a stauro-resistant Bcl2 kinase (SRK). We show that aurintricarboxylic acid (ATA), a nonpeptide activator of cellular MEK/mitogen-activated protein kinase (MAPK) kinase, can induce Ser-70 phosphorylation of Bcl2 and support survival of cells expressing wild-type but not the phosphorylation-incompetent S70A mutant Bcl2. A role for a MEK/MAPK as a responsible SRK was implicated because the highly specific MEK/MAPK inhibitor, PD98059, also can only partially inhibit IL-3-induced Bcl2 phosphorylation, whereas the combination of PD98059 and stauro completely blocks phosphorylation and synergistically enhances apoptosis. p44MAPK/extracellular signal-regulated kinase 1 (ERK1) and p42 MAPK/ERK2 are activated by IL-3, colocalize with mitochondrial Bcl2, and can directly phosphorylate Bcl2 on Ser-70 in a stauro-resistant manner both in vitro and in vivo. These findings suggest a role for the ERK1/2 kinases as SRKs. Thus, the SRKs can serve to functionally link the IL-3-stimulated proliferative and survival signaling pathways and, in a novel capacity, may explain how Bcl2 can suppress stauro-induced apoptosis. In addition, although the mechanism of regulation of Bcl2 by phosphorylation is not yet clear, our results indicate that phosphorylation may functionally stabilize the Bcl2-Bax heterodimerization.
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Affiliation(s)
- X Deng
- University of Florida Shands Cancer Center, Gainesville, FL 32610-0232, USA
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Srivastava RK, Mi QS, Hardwick JM, Longo DL. Deletion of the loop region of Bcl-2 completely blocks paclitaxel-induced apoptosis. Proc Natl Acad Sci U S A 1999; 96:3775-80. [PMID: 10097113 PMCID: PMC22370 DOI: 10.1073/pnas.96.7.3775] [Citation(s) in RCA: 269] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
At high concentrations, the tubule poison paclitaxel is able to kill cancer cells that express Bcl-2; it inhibits the antiapoptotic activity of Bcl-2 by inducing its phosphorylation. To localize the site on Bcl-2 regulated by phosphorylation, mutant forms of Bcl-2 were constructed. Mutant forms of Bcl-2 with an alteration in serine at amino acid 70 (S70A) or with deletion of a 60-aa loop region between the alpha1 and alpha2 helices (Deltaloop Bcl-2, which also deletes amino acid 70) were unable to be phosphorylated by paclitaxel treatment of MDA-MB-231 cells into which the genes for the mutant proteins were transfected. The Deltaloop mutant completely inhibited paclitaxel-induced apoptosis. In cells expressing the S70A mutant, paclitaxel induced about one-third the level of apoptosis seen with wild-type Bcl-2. To evaluate the role of mitogen-activated protein kinases (MAPKs) in Bcl-2 phosphorylation, the activation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38 was examined. Paclitaxel-induced apoptosis was associated with phosphorylation of Bcl-2 and activation of ERK and JNK MAPKs. If JNK activation was blocked by transfections with either a stress-activated protein kinase kinase dominant-negative (K-->R) gene (which prevents the activation of a kinase upstream of JNK) or MAPK phosphatase-1 gene (which dephosphorylates and inactivates JNK), Bcl-2 phosphorylation did not occur, and the cells were not killed by paclitaxel. By contrast, neither an ERK inhibitor (PD098059) nor p38 inhibitors (SB203580 and SB202190) had an effect on Bcl-2 phosphorylation. Thus, our data show that the antiapoptotic effects of Bcl-2 can be overcome by phosphorylation of Ser-70; forms of Bcl-2 lacking the loop region are much more effective at preventing apoptosis than wild-type Bcl-2 because they cannot be phosphorylated. JNK, but not ERK or p38 MAPK, appear to be involved in the phosphorylation of Bcl-2 induced by paclitaxel.
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Affiliation(s)
- R K Srivastava
- Laboratory of Immunology, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224-6825, USA
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