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Small-Molecule RAS Inhibitors as Anticancer Agents: Discovery, Development, and Mechanistic Studies. Int J Mol Sci 2022; 23:ijms23073706. [PMID: 35409064 PMCID: PMC8999084 DOI: 10.3390/ijms23073706] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/21/2022] [Accepted: 03/24/2022] [Indexed: 12/11/2022] Open
Abstract
Mutations of RAS oncogenes are responsible for about 30% of all human cancer types, including pancreatic, lung, and colorectal cancers. While KRAS1 is a pseudogene, mutation of KRAS2 (commonly known as KRAS oncogene) is directly or indirectly associated with human cancers. Among the RAS family, KRAS is the most abundant oncogene related to uncontrolled cellular proliferation to generate solid tumors in many types of cancer such as pancreatic carcinoma (over 80%), colon carcinoma (40-50%), lung carcinoma (30-50%), and other types of cancer. Once described as 'undruggable', RAS proteins have become 'druggable', at least to a certain extent, due to the continuous efforts made during the past four decades. In this account, we discuss the chemistry and biology (wherever available) of the small-molecule inhibitors (synthetic, semi-synthetic, and natural) of KRAS proteins that were published in the past decades. Commercial drugs, as well as investigational molecules from preliminary stages to clinical trials, are categorized and discussed in this study. In summary, this study presents an in-depth discussion of RAS proteins, classifies the RAS superfamily, and describes the molecular mechanism of small-molecule RAS inhibitors.
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Pandya N, Jain N, Kumar A. Interaction analysis of anti-cancer drug Methotrexate with bcl-2 promoter stabilization and its transcription regulation. GENE REPORTS 2021. [DOI: 10.1016/j.genrep.2021.101155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Gu Y, Lin D, Tang Y, Fei X, Wang C, Zhang B, Zhou J. A light-up probe targeting for Bcl-2 2345 G-quadruplex DNA with carbazole TO. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 191:180-188. [PMID: 29032342 DOI: 10.1016/j.saa.2017.10.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 09/25/2017] [Accepted: 10/03/2017] [Indexed: 06/07/2023]
Abstract
As its significant role, the selective recognition of G-quadruplex with specific structures and functions is important in biological and medicinal chemistry. Carbazole derivatives have been reported as a kind of fluorescent probe with many excellent optical properties. In the present study, the fluorescence of the dye (carbazole TO) increased almost 70 fold in the presence of bcl-2 2345 G4 compared to that alone in aqueous buffer condition with almost no fluorescence and 10-30 fold than those in the presence of other DNAs. The binding study results by activity inhibition of G4/Hemin peroxidase experiment, NMR titration and molecular docking simulation showed the high affinity and selectivity to bcl-2 2345 G4 arises from its end-stacking interaction with G-quartet. It is said that a facile approach with excellent sensitive, good selectivity and quick response for bcl-2 2345 G-quadruplex was developed and may be used for antitumor recognition or antitumor agents.
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Affiliation(s)
- Yingchun Gu
- Institute of Chemistry, Chinese Academy of Sciences (ICCAS), Beijing 100190, China; School of Science, Tianjin Chengjian University, Tianjin 300384, China
| | - Dayong Lin
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yalin Tang
- Institute of Chemistry, Chinese Academy of Sciences (ICCAS), Beijing 100190, China.
| | - Xuening Fei
- School of Science, Tianjin Chengjian University, Tianjin 300384, China; School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
| | - Cuihong Wang
- School of Science, Tianjin Chengjian University, Tianjin 300384, China
| | - Baolian Zhang
- School of Science, Tianjin Chengjian University, Tianjin 300384, China
| | - Jianguo Zhou
- School of Science, Tianjin Chengjian University, Tianjin 300384, China
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Targeting signaling pathways in multiple myeloma: Pathogenesis and implication for treatments. Cancer Lett 2018; 414:214-221. [DOI: 10.1016/j.canlet.2017.11.020] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 12/15/2022]
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Zhou H, Luo W, Zeng C, Zhang Y, Wang L, Yao W, Nie C. PP2A mediates apoptosis or autophagic cell death in multiple myeloma cell lines. Oncotarget 2017; 8:80770-80789. [PMID: 29113343 PMCID: PMC5655238 DOI: 10.18632/oncotarget.20415] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 06/27/2017] [Indexed: 02/05/2023] Open
Abstract
The crosstalk between apoptosis and autophagy contributes to tumorigenesis and cancer therapy. The process by which BetA (betulinic acid), a naturally occurring triterpenoid, regulates apoptosis and autophagy as a cancer therapy is unclear. In this study, we show for the first time that protein phosphatase 2A (PP2A) acts as a switch to regulate apoptosis and autophagic cell death mediated by BetA. Under normal conditions, caspase-3 is activated by the mitochondrial pathway upon BetA treatment. Activated caspase-3 cleaves the A subunit of PP2A (PP2A/A), resulting in the association of PP2A and Akt. This association inactivates Akt to initiate apoptosis. Overexpression of Bcl-2 attenuates the mitochondrial apoptosis pathway, resulting in caspase-3 inactivation and the dissociation of PP2A and Akt. PP2A isolated from Akt binds with DAPK to induce autophagic cell death. Meanwhile, in vivo tumor experiments have demonstrated that BetA initiates different types of cell death in a myeloma xenograft model. Thus, PP2A can shift myeloma cells from apoptosis to autophagic cell death. These findings have important implications for the therapeutic application of BetA, particularly against apoptosis-resistant cancers.
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Affiliation(s)
- Hang Zhou
- Department of Chemotherapy, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Wei Luo
- Department of Pharmacy, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Chao Zeng
- Department of Gastroenterology, the Third People's Hospital of Chengdu, Chengdu, China
| | - Yu Zhang
- Department of Oncology, Guizhou People's Hospital, Guizhou, China
| | - Liyang Wang
- Department of Chemotherapy, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Wenxiu Yao
- Department of Chemotherapy, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Chunlai Nie
- Department of Chemotherapy, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China.,Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu, China
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Apoptosis signaling and BCL-2 pathways provide opportunities for novel targeted therapeutic strategies in hematologic malignances. Blood Rev 2017; 32:8-28. [PMID: 28802908 DOI: 10.1016/j.blre.2017.08.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/05/2017] [Accepted: 08/06/2017] [Indexed: 12/14/2022]
Abstract
Apoptosis is an essential biological process involved in tissue homeostasis and immunity. Aberrations of the two main apoptotic pathways, extrinsic and intrinsic, have been identified in hematological malignancies; many of these aberrations are associated with pathogenesis, prognosis and resistance to standard chemotherapeutic agents. Targeting components of the apoptotic pathways, especially the chief regulatory BCL-2 family in the intrinsic pathway, has proved to be a promising therapeutic approach for patients with hematological malignances, with the expectation of enhanced efficacy and reduced adverse events. Continuous investigations regarding the biological importance of each of the BCL-2 family components and the clinical rationale to achieve optimal therapeutic outcomes, using either monotherapy or in combination with other targeted agents, have generated inspiring progress in the field. Genomic, epigenomic and biological analyses including BH3 profiling facilitate effective evaluation of treatment response, cancer recurrence and drug resistance. In this review, we summarize the biological features of each of the components in the BCL-2 apoptotic pathways, analyze the regulatory mechanisms and the pivotal roles of BCL-2 family members in the pathogenesis of major types of hematologic malignances, and evaluate the potential of apoptosis- and BCL-2-targeted strategies as effective approaches in anti-cancer therapies.
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Co-targeting of Bcl-2 and mTOR pathway triggers synergistic apoptosis in BH3 mimetics resistant acute lymphoblastic leukemia. Oncotarget 2016; 6:32089-103. [PMID: 26392332 PMCID: PMC4741661 DOI: 10.18632/oncotarget.5156] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 09/03/2015] [Indexed: 01/09/2023] Open
Abstract
Several chemo-resistance mechanisms including the Bcl-2 protein family overexpression and constitutive activation of the PI3K/Akt/mTOR signaling have been documented in acute lymphoblastic leukemia (ALL), encouraging targeted approaches to circumvent this clinical problem. Here we analyzed the activity of the BH3 mimetic ABT-737 in ALL, exploring the synergistic effects with the mTOR inhibitor CCI-779 on ABT-737 resistant cells. We showed that a low Mcl-1/Bcl-2 plus Bcl-xL protein ratio determined ABT-737 responsiveness. ABT-737 exposure further decreased Mcl-1, inducing apoptosis on sensitive models and primary samples, while not affecting resistant cells. Co-inhibition of Bcl-2 and the mTOR pathway resulted cytotoxic on ABT-737 resistant models, by downregulating mTORC1 activity and Mcl-1 in a proteasome-independent manner. Although Mcl-1 seemed to be critical, ectopic modulation did not correlate with apoptosis changes. Importantly, dual targeting proved effective on ABT-737 resistant samples, showing additive/synergistic effects. Together, our results show the efficacy of BH3 mimetics as single agent in the majority of the ALL samples and demonstrate that resistance to ABT-737 mostly correlated with Mcl-1 overexpression. Co-targeting of the Bcl-2 protein family and mTOR pathway enhanced drug-induced cytotoxicity by suppressing Mcl-1, providing a novel therapeutic approach to overcome BH3 mimetics resistance in ALL.
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Doi K, Gowda K, Liu Q, Lin JM, Sung SS, Dower C, Claxton D, Loughran TP, Amin S, Wang HG. Pyoluteorin derivatives induce Mcl-1 degradation and apoptosis in hematological cancer cells. Cancer Biol Ther 2015; 15:1688-99. [PMID: 25535900 DOI: 10.4161/15384047.2014.972799] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Mcl-1, a pro-survival member of the Bcl-2 protein family, is an attractive target for cancer therapy. We have recently identified the natural product marinopyrrole A (maritoclax) as a novel small molecule Mcl-1 inhibitor. Here, we describe the structure-activity relationship study of pyoluteorin derivatives based on maritoclax. To date, we synthesized over 30 derivatives of maritoclax and evaluated their inhibitory actions and cytotoxicity toward Mcl-1-dependent cell lines. As a result, several functional groups were identified in the pyoluteorin motif that significantly potentiate biological activity. A number of such derivatives, KS04 and KS18, interacted with Mcl-1 in a conserved fashion according to NMR spectroscopy and molecular modeling. KS04 and KS18 induced apoptosis selectively in Mcl-1-dependent but not Bcl-2-dependent K562 cells through selective Mcl-1 down-regulation, and synergistically enhanced apoptosis in combination with ABT-737. Moreover, the intraperitoneal administration of KS18 (10 mg/kg/d) and ABT-737 (20 mg/kg/d) significantly suppressed the growth of ABT-737-resistant HL-60 xenografts in nude mice without apparent toxicity. Overall, we identified the pharmacophore of pyoluteorin derivatives that act as potent and promising Mcl-1 antagonists against Mcl-1-dependent hematological cancers.
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Key Words
- ABTR, ABT-737 resistant
- AML, Acute Myeloid Leukemia
- AUCinf, area under curve extrapolated to time infinity
- AUClast, area under curve until last observed timepoint
- Apoptosis
- BH3, Bcl-2 homology domain 3
- Bcl-2 family
- Bcl-2, B-cell lymphoma-2
- CHX, Cycloheximide
- CL, rate of plasma clearance
- Cmax, maximal plasma concentration
- EC50, Half maximal effective concentration
- IRES, Internal ribosome entry site
- LD50, median lethal dose
- MTD, Maximal tolerated dose
- Mcl-1
- Mcl-1, Myeloid cell leukemia-1
- NMR, Nuclear magnetic resonance
- PARP, Poly (ADP-ribose) polymerase
- SAR, Structure-activity relationship
- T1/2, plasma half-life
- Tmax, time to maximal plasma concentration
- VD, Volume of distribution
- i.p., Intraperitoneal
- leukemia
- lymphoma
- maritoclax
- multiple myeloma
- pyoluteorin
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Affiliation(s)
- Kenichiro Doi
- a Department of Pediatrics ; Pennsylvania State University College of Medicine ; Hershey , PA USA
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Ailawadhi S, Miecznikowski J, Gaile DP, Wang D, Sher T, Mulligan G, Bryant B, Wilding GE, Mashtare T, Stein L, Masood A, Neuwirth R, Lee KP, Chanan-Khan A. Bortezomib mitigates adverse prognosis conferred by Bcl-2 overexpression in patients with relapsed/refractory multiple myeloma. Leuk Lymphoma 2011; 53:1174-82. [DOI: 10.3109/10428194.2011.637212] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Sikander Ailawadhi
- Division of Hematology, University of Southern California,
Los Angeles, CA, USA
| | | | | | - Dongliang Wang
- Department of Medicine, Roswell Park Cancer Institute,
Buffalo, NY, USA
| | - Taimur Sher
- Department of Public Health and Preventive Medicine, SUNY Upstate Medical University,
Syracuse, NY, USA
| | | | - Barb Bryant
- Millennium Pharmaceuticals,
Cambridge, MA, USA
| | | | | | | | - Aisha Masood
- Department of Public Health and Preventive Medicine, SUNY Upstate Medical University,
Syracuse, NY, USA
| | | | - Kelvin P. Lee
- Department of Public Health and Preventive Medicine, SUNY Upstate Medical University,
Syracuse, NY, USA
| | - Asher Chanan-Khan
- Department of Public Health and Preventive Medicine, SUNY Upstate Medical University,
Syracuse, NY, USA
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10
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Delmore JE, Issa GC, Lemieux ME, Rahl PB, Shi J, Jacobs HM, Kastritis E, Gilpatrick T, Paranal RM, Qi J, Chesi M, Schinzel A, McKeown MR, Heffernan TP, Vakoc CR, Bergsagel PL, Ghobrial IM, Richardson PG, Young RA, Hahn WC, Anderson KC, Kung AL, Bradner JE, Mitsiades CS. BET bromodomain inhibition as a therapeutic strategy to target c-Myc. Cell 2011; 146:904-17. [PMID: 21889194 PMCID: PMC3187920 DOI: 10.1016/j.cell.2011.08.017] [Citation(s) in RCA: 2218] [Impact Index Per Article: 170.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 08/13/2011] [Accepted: 08/15/2011] [Indexed: 02/07/2023]
Abstract
MYC contributes to the pathogenesis of a majority of human cancers, yet strategies to modulate the function of the c-Myc oncoprotein do not exist. Toward this objective, we have targeted MYC transcription by interfering with chromatin-dependent signal transduction to RNA polymerase, specifically by inhibiting the acetyl-lysine recognition domains (bromodomains) of putative coactivator proteins implicated in transcriptional initiation and elongation. Using a selective small-molecule bromodomain inhibitor, JQ1, we identify BET bromodomain proteins as regulatory factors for c-Myc. BET inhibition by JQ1 downregulates MYC transcription, followed by genome-wide downregulation of Myc-dependent target genes. In experimental models of multiple myeloma, a Myc-dependent hematologic malignancy, JQ1 produces a potent antiproliferative effect associated with cell-cycle arrest and cellular senescence. Efficacy of JQ1 in three murine models of multiple myeloma establishes the therapeutic rationale for BET bromodomain inhibition in this disease and other malignancies characterized by pathologic activation of c-Myc.
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Affiliation(s)
- Jake E. Delmore
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Ghayas C. Issa
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Madeleine E. Lemieux
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Children’s Hospital Boston, 450 Brookline Avenue, Boston, MA 02215
| | - Peter B. Rahl
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142
| | - Junwei Shi
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724
| | - Hannah M. Jacobs
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Efstathios Kastritis
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Timothy Gilpatrick
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Ronald M. Paranal
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Jun Qi
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Marta Chesi
- Comprehensive Cancer Center, Mayo Clinic Arizona, Scottsdale, AZ 85259
| | - Anna Schinzel
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Michael R. McKeown
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Timothy P. Heffernan
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
| | - Christopher R. Vakoc
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724
| | - P. Leif Bergsagel
- Comprehensive Cancer Center, Mayo Clinic Arizona, Scottsdale, AZ 85259
| | - Irene M. Ghobrial
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
- Department of Medicine, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115
| | - Paul G. Richardson
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
- Department of Medicine, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115
| | - Richard A. Young
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - William C. Hahn
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
- Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, MA 02142
| | - Kenneth C. Anderson
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
- Department of Medicine, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115
| | - Andrew L. Kung
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Children’s Hospital Boston, 450 Brookline Avenue, Boston, MA 02215
| | - James E. Bradner
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
- Department of Medicine, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115
| | - Constantine S. Mitsiades
- Department of Medical Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215
- Department of Medicine, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115
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Gao J, Cai Q, Lu J, Jha HC, Robertson ES. Upregulation of cellular Bcl-2 by the KSHV encoded RTA promotes virion production. PLoS One 2011; 6:e23892. [PMID: 21901143 PMCID: PMC3162012 DOI: 10.1371/journal.pone.0023892] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 07/27/2011] [Indexed: 11/18/2022] Open
Abstract
Apoptosis of virus infected cells can restrict or dampen full blown virus propagation and this can serve as a protective mechanism against virus infection. Consequently, viruses can also delay programmed cell death by enhancing the expression of anti-apoptotic proteins. Human Bcl-2 is expressed on the surface of the mitochondrial membrane and functions as the regulator of the delicate balance between cell survival and apoptosis. In this report, we showed that the replication and transcription activator (RTA) encoded by KSHV ORF 50, a key regulator for KSHV reactivation from latent to lytic infection, upregulates the mRNA and protein levels of Bcl-2 in 293 cells, and TPA-induced KSHV-infected cells. Further analysis revealed that upregulation of the cellular Bcl-2 promoter by RTA is dose-dependent and acts through targeting of the CCN9GG motifs within the Bcl-2 promoter. The Bcl-2 P2 but not the P1 promoter is primarily responsive to RTA. The results of ChIP confirmed the direct interaction of RTA protein with the CCN9GG motifs. Knockdown of cellular Bcl-2 by lentivirus-delivered small hairpin RNA (shRNA) resulted in increased cell apoptosis and decreased virion production in KSHV-infected cells. These findings provide an insight into another mechanism by which KSHV utilizes the intrinsic apoptosis signaling pathways for prolonging the survival of lytically infected host cells to allow for maximum production of virus progeny.
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Affiliation(s)
- Jianming Gao
- Department of Microbiology and the Tumor Virology Program of the Abramson Cancer Center, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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Straten PT, Andersen MH. The anti-apoptotic members of the Bcl-2 family are attractive tumor-associated antigens. Oncotarget 2011; 1:239-45. [PMID: 21304176 DOI: 10.18632/oncotarget.100804] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Anti-apoptotic members of the Bcl-2 family (Bcl-2, Bcl-X(L) and Mcl-2) are pivotal regulators of apoptotic cell death. They are all highly overexpressed in cancers of different origin in which they enhance the survival of the cancer cells. Consequently, they represent prime candidates for anti-cancer therapy and specific antisense oligonucleotides or small molecule inhibitors have shown broad anti-cancer activities in pre-clinical models and are currently tested in clinical trials. In addition, immune-mediated tumor destruction is emerging as an interesting modality to treat cancer patients. Notably, spontaneous cellular immune responses against the Bcl-2 family proteins have been identified as frequent features in cancer patients underscoring that these proteins are natural targets for the immune system. Thus, Bcl-2 family may serve as an important and widely applicable target for anti-cancer immunotherapeutic strategies, alone or in the combination with conventional therapy. Here, we summarize the current knowledge of Bcl-2 family proteins as T-cell antigens, which has set the stage for the first explorative trial using these antigens in therapeutic vaccinations against cancer, and discuss future opportunities.
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Affiliation(s)
- Per thor Straten
- Center for Cancer Immune Therapy, Department of Hematology, Herlev University Hospital, Denmark
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Thor Straten P, Andersen MH. The anti-apoptotic members of the Bcl-2 family are attractive tumor-associated antigens. Oncotarget 2010; 1:239-245. [PMID: 21304176 PMCID: PMC3248102 DOI: 10.18632/oncotarget.134] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Accepted: 08/09/2010] [Indexed: 11/25/2022] Open
Abstract
Anti-apoptotic members of the Bcl-2 family (Bcl-2, Bcl-X(L) and Mcl-2) are pivotal regulators of apoptotic cell death. They are all highly overexpressed in cancers of different origin in which they enhance the survival of the cancer cells. Consequently, they represent prime candidates for anti-cancer therapy and specific antisense oligonucleotides or small molecule inhibitors have shown broad anti-cancer activities in pre-clinical models and are currently tested in clinical trials. In addition, immune-mediated tumor destruction is emerging as an interesting modality to treat cancer patients. Notably, spontaneous cellular immune responses against the Bcl-2 family proteins have been identified as frequent features in cancer patients underscoring that these proteins are natural targets for the immune system. Thus, Bcl-2 family may serve as an important and widely applicable target for anti-cancer immunotherapeutic strategies, alone or in the combination with conventional therapy. Here, we summarize the current knowledge of Bcl-2 family proteins as T-cell antigens, which has set the stage for the first explorative trial using these antigens in therapeutic vaccinations against cancer, and discuss future opportunities.
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14
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Wang XD, Ou TM, Lu YJ, Li Z, Xu Z, Xi C, Tan JH, Huang SL, An LK, Li D, Gu LQ, Huang ZS. Turning off transcription of the bcl-2 gene by stabilizing the bcl-2 promoter quadruplex with quindoline derivatives. J Med Chem 2010; 53:4390-8. [PMID: 20481493 DOI: 10.1021/jm100445e] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human bcl-2 gene is an apoptosis-related oncogene containing a GC-rich sequence which is located upstream from P1 promoter and has the potential to form G-quadruplex structures. However, the regulatory role of the quadruplex and the effect of its ligands on bcl-2 have not been clarified. Here, we demonstrated that the G-quadruplex structure was disrupted when partial mutation of G --> A was made, resulting in a 2-fold increase in basal transcriptional activity of bcl-2 promoter. Quindoline derivatives, the highly active G-quadruplex ligands developed by our group, could significantly suppress bcl-2 transcriptional activation but had less effect on mutated bcl-2 transcription. These results provided direct evidence that G-quadruplex structure formed in bcl-2 promoter region could function as a transcriptional repressor element, and G-quadruplex specific ligands could regulate the transcription of bcl-2 through stabilization of quadruplex structure. The results further indicated that quindoline derivatives could induce apoptosis of HL-60 tumor cells.
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Affiliation(s)
- Xiao-Dong Wang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
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15
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González-Herrero I, Vicente-Dueñas C, Orfao A, Flores T, Jiménez R, Cobaleda C, Sánchez-García I. Bcl2 is not required for the development and maintenance of leukemia stem cells in mice. Carcinogenesis 2010; 31:1292-7. [PMID: 20299524 DOI: 10.1093/carcin/bgq062] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The existence of leukemia stem cells (LSCs) responsible for tumor maintenance has been firmly established. Therefore, therapeutic targeting of these LSCs may have a profound impact on cancer eradication. The anti-apoptotic protein Bcl2 has been proposed as a therapeutic target, but its role in LSC biology has not been investigated. In order to understand the role of Bcl2 in LSC generation and maintenance, we have taken advantage of our Sca1-BCRABLp210 mouse model of human chronic myeloid leukemia and bcl2 gene-targeted mice. This study provides genetic evidence that the inhibition of Bcl2 is not critical for the generation, selection or maintenance of the tumor initiating and maintaining cells in mice.
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Affiliation(s)
- Inés González-Herrero
- Experimental Therapeutics and Translational Oncology Program, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas/Universidad de Salamanca, Campus Miguel Unamuno sin número, 37007 Salamanca, Spain
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Ackler S, Mitten MJ, Foster K, Oleksijew A, Refici M, Tahir SK, Xiao Y, Tse C, Frost DJ, Fesik SW, Rosenberg SH, Elmore SW, Shoemaker AR. The Bcl-2 inhibitor ABT-263 enhances the response of multiple chemotherapeutic regimens in hematologic tumors in vivo. Cancer Chemother Pharmacol 2010; 66:869-80. [PMID: 20099064 DOI: 10.1007/s00280-009-1232-1] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Accepted: 12/24/2009] [Indexed: 12/01/2022]
Abstract
PURPOSE This study was designed to test the ability of the Bcl-2 family inhibitor ABT-263 to potentiate commonly used chemotherapeutic agents and regimens in hematologic tumor models. METHODS Models of B-cell lymphoma and multiple myeloma were tested in vitro and in vivo with ABT-263 in combination with standard chemotherapeutic regimens, including VAP, CHOP and R-CHOP, as well as single cytotoxic agents including etoposide, rituximab, bortezomib and cyclophosphamide. Alterations in Bcl-2 family member expression patterns were analyzed to define mechanisms of potentiation. RESULTS ABT-263 was additive with etoposide, vincristine and VAP in vitro in the diffuse large B-cell lymphoma line (DLBCL) DoHH-2, while rituximab potentiated its activity in SuDHL-4. Bortezomib strongly synergized with ABT-263 in the mantle cell lymphoma line Granta 519. Treatment of DoHH-2 with etoposide was associated with an increase in Puma expression, while bortezomib upregulated Noxa expression in Granta 519. Combination of ABT-263 with cytotoxic agents demonstrated superior tumor growth inhibition and delay in multiple models versus cytotoxic therapy alone, along with significant improvements in tumor response rates. CONCLUSIONS Inhibition of the Bcl-2 family of proteins by ABT-263 enhances the cytotoxicity of multiple chemotherapeutics in hematologic tumors and represents a promising addition to the therapeutic arsenal for treatment of these diseases.
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Affiliation(s)
- Scott Ackler
- Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, IL, USA.
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17
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Beaupre DM, McCafferty-Grad J, Bahlis NJ, Boise LH, Lichtenheld MG. Farnesyl Transferase Inhibitors Enhance Death Receptor Signals and Induce Apoptosis in Multiple Myeloma Cells. Leuk Lymphoma 2009; 44:2123-34. [PMID: 14959858 DOI: 10.1080/1042819031000116652] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Multiple myeloma is an incurable plasma cell malignancy in which Ras may be constitutively active either via interleukin-6 (IL-6) receptor signaling or by mutation. Inactivation of Ras may be achieved with farnesyl transferase (FTase) inhibitors a class of drugs which have shown promise in clinical trials particularly in patients with acute leukemia. This report investigates the efficacy of two distinct classes of FTase inhibitors in diverse myeloma cell lines and primary isolates. While Ras signaling has traditionally been linked to myeloma cell growth, we found that these compounds also potently triggered cell death. Death induced by perillic acid (PA) was caspase dependent without evidence of death receptor activation. Apoptosis was associated with mitochondrial membrane depolarization and activation of caspase-9 and 3 but proceeded despite over-expression of Bcl-XL a known correlate of relapsed and chemorefractory myeloma. In addition, Fas ligand and TRAIL mediated apoptosis was potentiated in death receptor resistant (U266) and sensitive (RPMI 8226/S) cell lines. Of clinical relevance, the FTase inhibitor R115777 induced cell death in myeloma lines at doses observed in clinical trials. Furthermore, both R115777 and PA induced cell death in primary isolates with relative specificity. Taken together these preclinical data provide evidence that FTase inhibitors may be an effective therapeutic modality for the treatment of multiple myeloma.
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Affiliation(s)
- Darrin M Beaupre
- Division of Hematology and Oncology, Department of Medicine, Sylvester Cancer Center, USA
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18
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Abstract
PURPOSE OF REVIEW This review aims to summarize recent advances in the mechanisms through which the activation of the transcription factor NF-kappaB contributes to the pathogenesis of multiple myeloma. RECENT FINDINGS This transcription factor regulates expression of numerous genes involved in multiple myeloma pathogenesis, including growth, survival, immortalization, angiogenesis and metastasis. Recently, mutations of NF-kappaB signaling molecules have been identified in multiple myeloma cells. In addition, interactions between multiple myeloma cells and the bone marrow environment play critical roles in NF-kappaB activation as well as in multiple myeloma pathogenesis. Moreover, several drugs that are effective against multiple myeloma, including bortezomib, thalidomide, lenalidomide and arsenic trioxide, have been found to block activation of NF-kappaB. The combination of conventional chemotherapeutic drugs and those that block NF-kappaB activation has now proven to be effective in the treatment of multiple myeloma. SUMMARY Recent studies further underscore the critical role of NF-kappaB in multiple myeloma pathogenesis and have provided the rationale for multiple myeloma therapy with NF-kappaB-specific inhibitors combined with conventional chemotherapeutic drugs.
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19
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Sutheesophon K, Kobayashi Y, Takatoku MA, Ozawa K, Kano Y, Ishii H, Furukawa Y. Histone deacetylase inhibitor depsipeptide (FK228) induces apoptosis in leukemic cells by facilitating mitochondrial translocation of Bax, which is enhanced by the proteasome inhibitor bortezomib. Acta Haematol 2006; 115:78-90. [PMID: 16424655 DOI: 10.1159/000089471] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2005] [Accepted: 05/11/2005] [Indexed: 12/13/2022]
Abstract
Histone deacetylase (HDAC) inhibitors are promising candidates for molecular-targeted therapy for leukemia. In this study, we investigated the mechanisms of cytotoxic effects of depsipeptide (FK228), one of the most effective HDAC inhibitors against leukemia, using human myeloid leukemic cell lines HL-60 and K562. We found that FK228 activated caspase-9 and a subsequent caspase cascade by perturbing the mitochondrial membrane to release cytochrome c, which was almost completely blocked by overexpression of Bcl-2. The mitochondrial damage was caused by the translocation of Bax but not other pro-apoptotic Bcl-2 family proteins to the mitochondria. FK228 did not affect the interaction between Bax and Bax adaptor proteins such as 14-3-3theta and Ku70. FK228-induced apoptosis and mitochondrial translocation of Bax were markedly enhanced by the proteasome inhibitor bortezomib. The synergistic action of FK228 and bortezomib was at least partly mediated through conformational changes in Bax, which facilitate its translocation to the mitochondria. These results suggest that the combination of HDAC inhibitors and proteasome inhibitors is useful in the treatment of leukemia especially in the context of molecular-targeted therapy. The status of Bcl-2 and Bax may influence the sensitivity of tumors to this combination and thus can be a target of further therapeutic intervention.
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Affiliation(s)
- Krittaya Sutheesophon
- Division of Stem Cell Regulation, Center for Molecular Medicine, Jichi Medical School, Tochigi, Japan
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20
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Abstract
Apoptosis is deregulated in many cancers, making it difficult to kill tumours. Drugs that restore the normal apoptotic pathways have the potential for effectively treating cancers that depend on aberrations of the apoptotic pathway to stay alive. Apoptosis targets that are currently being explored for cancer drug discovery include the tumour-necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptors, the BCL2 family of anti-apoptotic proteins, inhibitor of apoptosis (IAP) proteins and MDM2.
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Affiliation(s)
- Stephen W Fesik
- Cancer Research, Abbott Laboratories, Department R460, Building AP10-LL, 100 Abbott Park Road, Abbott Park, Illinois 60064, USA.
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21
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Badros AZ, Goloubeva O, Rapoport AP, Ratterree B, Gahres N, Meisenberg B, Takebe N, Heyman M, Zwiebel J, Streicher H, Gocke CD, Tomic D, Flaws JA, Zhang B, Fenton RG. Phase II study of G3139, a Bcl-2 antisense oligonucleotide, in combination with dexamethasone and thalidomide in relapsed multiple myeloma patients. J Clin Oncol 2005; 23:4089-99. [PMID: 15867202 DOI: 10.1200/jco.2005.14.381] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE Bcl-2 regulates the mitochondrial apoptosis pathway that promotes chemotherapy resistance. Bcl-2 antisense oligonucleotide, G3139, targets Bcl-2 mRNA. PATIENTS AND METHODS G3139 was administered (3 to 7 mg/kg/d for 7 days) by continuous intravenous infusion. On day 4, patients started thalidomide (100 to 400 mg as tolerated) and dexamethasone (40 mg daily for 4 days) on 21-day cycles for three cycles. Stable and responding patients continued on 35-day cycles for 2 years. RESULTS Thirty-three patients (median age, 60 years; range, 28 to 76 years) received 220 cycles. Patients received a median of three prior regimens including thalidomide (n = 15) and stem-cell transplantation (n = 31). The regimen was well tolerated; the median number of cycles per patient was eight (range, one to 16+ cycles). Toxicities included reversible increase in creatinine, thrombocytopenia, neutropenia, fatigue, anorexia, constipation, fever, neuropathy, edema, electrolyte disturbances, and hyperglycemia. Fifty-five percent of patients had objective responses, including two complete responses (CRs), four near CRs (positive immunofixation), and 12 partial responses; six patients had minimal responses (MRs). Of patients who received prior thalidomide, seven had objective responses, and three had MRs. The median duration of response was 13 months, and estimated progression-free and overall survival times were 12 and 17.4 months, respectively. Responding patients had significant increase in polyclonal immunoglobulin M (P = .005), indicating innate immune system activation. Western blot analysis of Bcl-2 protein isolated from myeloma cells before and after G3139 demonstrated a decrease of Bcl-2 levels in three of seven patients compared with six of nine patients using reverse transcriptase polymerase chain reaction. CONCLUSION G3139, dexamethasone, and thalidomide are well tolerated and result in encouraging clinical responses in relapsed multiple myeloma patients.
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Affiliation(s)
- Ashraf Z Badros
- Greenebaum Cancer Center, Department of Pathology, University of Maryland, 22 S Greene St, Baltimore, MD 21201, USA.
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22
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Letai A, Sorcinelli MD, Beard C, Korsmeyer SJ. Antiapoptotic BCL-2 is required for maintenance of a model leukemia. Cancer Cell 2004; 6:241-9. [PMID: 15380515 DOI: 10.1016/j.ccr.2004.07.011] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2004] [Revised: 07/02/2004] [Accepted: 07/08/2004] [Indexed: 01/09/2023]
Abstract
Resistance to apoptosis, often achieved by the overexpression of antiapoptotic proteins, is common and perhaps required in the genesis of cancer. However, it remains uncertain whether apoptotic defects are essential for tumor maintenance. To test this, we generated mice expressing a conditional BCL-2 gene and constitutive c-myc that develop lymphoblastic leukemia. Eliminating BCL-2 yielded rapid loss of leukemic cells and significantly prolonged survival, formally validating BCL-2 as a rational target for cancer therapy. Loss of this single molecule resulted in cell death, despite or perhaps attributable to the presence of other oncogenic events. This suggests a generalizable model in which aberrations inherent to cancer generate tonic death signals that would otherwise kill the cell if not opposed by a requisite apoptotic defect(s).
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Affiliation(s)
- Anthony Letai
- Howard Hughes Medical Institute, Department of Pathology, Harvard Medical School, Dana-Farber Cancer Institute, Boston, MA 02115, USA
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23
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van de Donk NWCJ, de Weerdt O, Veth G, Eurelings M, van Stralen E, Frankel SR, Hagenbeek A, Bloem AC, Lokhorst HM. G3139, a Bcl-2 antisense oligodeoxynucleotide, induces clinical responses in VAD refractory myeloma. Leukemia 2004; 18:1078-84. [PMID: 15085157 DOI: 10.1038/sj.leu.2403363] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Expression of Bcl-2 in multiple myeloma is associated with resistance to chemotherapeutic drugs. Conversely, suppression of Bcl-2 enhanced the chemosensitivity of myeloma cells in vitro. G3139 is an antisense oligodeoxynucleotide targeted to the first six codons of the Bcl-2 mRNA open reading frame. In this study, G3139 was delivered as a continuous intravenous infusion for 7 days at a fixed dose of 7 mg/kg/day in combination with VAD (vincristine, adriamycin, and dexamethasone) chemotherapy. In total, 10 heavily pretreated patients with refractory myeloma participated in this trial, including eight patients with VAD refractory disease. The combination of G3139 and VAD was feasible and well tolerated. Seven patients (70%) responded including four patients (40%) with a partial response and three patients (30%) with a minor response. Median progression-free survival was 6 months (range, 2-7+ months) and median overall survival has not been reached. G3139 downregulated Bcl-2 protein levels in peripheral blood circulating myeloma cells, B cells, T cells, and monocytes. These results indicate that G3139 may overcome classical resistance and restore sensitivity of myeloma tumor cells to VAD chemotherapy.
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Affiliation(s)
- N W C J van de Donk
- Department of Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
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24
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Evens AM, Prachand S, Shi B, Paniaqua M, Gordon LI, Gartenhaus RB. Imexon-Induced Apoptosis in Multiple Myeloma Tumor Cells Is Caspase-8 Dependent. Clin Cancer Res 2004; 10:1481-91. [PMID: 14977852 DOI: 10.1158/1078-0432.ccr-1058-03] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Imexon is a 2-cyanoaziridine agent that has been shown to inhibit growth of chemotherapy-sensitive myeloma cells through apoptosis with decreased cellular stores of glutathione and increased reactive oxygen species (ROS). We examined the mechanism of imexon cytotoxicity in a diverse panel of dexamethasone and chemotherapy-sensitive and -resistant myeloma cell lines. EXPERIMENTAL DESIGN We examined cellular cytotoxicity, apoptosis, and changes in redox state in dexamethasone-sensitive (C2E3), dexamethasone-resistant (1-310 and 1-414), chemotherapy-sensitive (RPMI-8226), and chemotherapy-resistant (DOX-1V and DOX-10V) myeloma cell lines. RESULTS We found significant cytotoxicity after 48-h incubation with imexon (80-160 microM) in dexamethasone and chemotherapy-sensitive and -resistant myeloma cell lines in a time- and dose-dependent manner. The mechanism of imexon cytotoxicity in all cell lines was related to induction of apoptosis with the presence of cleaved caspase-3. Moreover, after imexon exposure in C2E3 and 1-414 cell lines, we demonstrated caspase-8-dependent apoptosis. Bcl-2:bax was proapoptotic with imexon in C2E3, whereas bcl-2:bax was independent of steroid resistance, chemotherapy sensitivity, and chemotherapy resistance. Depletion of intracellular glutathione was documented in RPMI-8226 at high imexon concentrations (>or=225 microM) but not in other cell lines. Furthermore, ROS were found in C2E3, RPMI-8226, and 1-310 only at high imexon concentrations, whereas a sensitive marker of oxidative DNA damage, 8-hydroxydeoxyguanosine, was not increased in any cell line. CONCLUSIONS Our results demonstrate that imexon has significant broad antimyeloma activity that is mediated through apoptotic mechanisms that is not dependent on production of ROS. Moreover, we have identified a mechanism of cytotoxicity in dexamethasone-sensitive and -resistant myeloma cells induced by imexon that is caspase-8 dependent.
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Affiliation(s)
- Andrew M Evens
- Departments of Medicine and Pathology, Feinberg School of Medicine and the Robert H Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois 60611, USA
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25
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Beaupre DM, Cepero E, Obeng EA, Boise LH, Lichtenheld MG. R115777 induces Ras-independent apoptosis of myeloma cells via multiple intrinsic pathways. Mol Cancer Ther 2004. [DOI: 10.1158/1535-7163.179.3.2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Ras activation is frequently observed in multiple myeloma either by mutation or through interleukin-6 receptor signaling. Recently, drugs designed to inhibit Ras have shown promise in preclinical myeloma models and in clinical trials. In this report, we characterize the pathways by which the clinically tested farnesyl transferase inhibitor (FTI) R115777 induces apoptosis in multiple myeloma cells. Contrary to the proposed mechanistic action of FTIs, we found that R115777 induces cell death despite Ras prenylation implying participation of Ras-independent mechanism(s). Apoptosis proceeded via an intrinsic cascade and was associated with an increase in the expression and activity of Bax. Bax activation correlated with a loss of mitochondrial membrane integrity and activation of the endoplasmic reticulum (ER) stress response. These pathways activate caspase-9 and consistent with this, cell death was prevented by caspase-9 blockade. Interestingly, cells overexpressing Bcl-XL remained partially sensitive to R115777 despite suppression of mitochondrial membrane dysfunction and ER-related stress. Taken together, these results indicate that R115777 induces apoptosis in a Ras-independent fashion via multiple intrinsic pathways.
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Affiliation(s)
- Darrin M. Beaupre
- 1Department of Medicine, Division of Hematology and Oncology,
- 2Sylvester Cancer Center, and
| | - Enrique Cepero
- 3Department of Microbiology and Immunology, University of Miami School of Medicine, Miami, FL
| | - Esther A. Obeng
- 3Department of Microbiology and Immunology, University of Miami School of Medicine, Miami, FL
| | - Lawrence H. Boise
- 2Sylvester Cancer Center, and
- 3Department of Microbiology and Immunology, University of Miami School of Medicine, Miami, FL
| | - Mathias G. Lichtenheld
- 2Sylvester Cancer Center, and
- 3Department of Microbiology and Immunology, University of Miami School of Medicine, Miami, FL
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26
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Shangary S, Johnson DE. Recent advances in the development of anticancer agents targeting cell death inhibitors in the Bcl-2 protein family. Leukemia 2003; 17:1470-81. [PMID: 12886234 DOI: 10.1038/sj.leu.2403029] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Hematopoietic malignancies frequently are characterized by defects in apoptosis signaling. This renders the malignant cells resistant to endogenous apoptotic stimuli, as well as exogenous stimuli, such as chemotherapy drugs and radiation. The defective apoptosis seen in human cancers often results from overexpression of antiapoptotic proteins in the Bcl-2 protein family, particularly Bcl-2 and Bcl-X(L). A great deal of effort is currently aimed at developing novel agents to inhibit the expression or function of these proteins. Antisense agents directed against Bcl-2 mRNA are showing considerable promise in clinical trials. In addition, detailed knowledge of the structures of Bcl-2 and Bcl-X(L), coupled with high-throughput and computer-assisted screening of chemical libraries, has led to the identification of a number of short peptides and small organic molecules capable of inhibiting Bcl-2 and Bcl-X(L) function. These newly described agents hold considerable promise for enhancing the chemo- and radiation sensitivities of Bcl-2- and Bcl-X(L)-overexpressing cancers. This review will highlight recent advances in the development and testing of agents targeting cell death inhibitors in the Bcl-2 protein family.
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Affiliation(s)
- S Shangary
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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27
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Jourdan M, Veyrune JL, Vos JD, Redal N, Couderc G, Klein B. A major role for Mcl-1 antiapoptotic protein in the IL-6-induced survival of human myeloma cells. Oncogene 2003; 22:2950-9. [PMID: 12771946 PMCID: PMC2396235 DOI: 10.1038/sj.onc.1206423] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Interleukin-6 (IL-6) is a major survival factor for malignant plasma cells involved in multiple myeloma. Using an RNase protection assay, we looked for gene expression of 10 anti- and proapoptotic Bcl-2-family proteins in 12 IL-6-dependent human myeloma cell lines (HMCL). A high Mcl-1 gene expression was found in all HMCLs and the other genes were variably expressed. Out of the 10 Bcl-2-family members, only the Mcl-1 gene was regulated by IL-6. Upon starvation of IL-6, Mcl-1 gene expression decreased in association with myeloma cell apoptosis and was upregulated after adding IL-6 again in association with myeloma cell survival. A constitutive Mcl-1 expression was induced with an Mcl-1-GFP retrovirus in two IL-6-dependent HMCLs. The Mcl-1 HMCLs have a marked reduced apoptosis upon IL-6 starvation compared to HMCLs transduced with control GFP retrovirus and may grow without adding IL-6. These data emphasize the major role of Mcl-1 antiapoptotic protein in the IL-6-induced survival of human myeloma cells.
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Affiliation(s)
| | | | | | | | | | - Bernard Klein
- * Correspondence should be adressed to: Bernard Klein
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28
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Hockenbery DM, Giedt CD, O'Neill JW, Manion MK, Banker DE. Mitochondria and apoptosis: new therapeutic targets. Adv Cancer Res 2003; 85:203-42. [PMID: 12374287 DOI: 10.1016/s0065-230x(02)85007-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- David M Hockenbery
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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29
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van de Donk NWCJ, Kamphuis MMJ, van Dijk M, Borst HPE, Bloem AC, Lokhorst HM. Chemosensitization of myeloma plasma cells by an antisense-mediated downregulation of Bcl-2 protein. Leukemia 2003; 17:211-9. [PMID: 12529680 DOI: 10.1038/sj.leu.2402768] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2002] [Accepted: 08/13/2002] [Indexed: 02/07/2023]
Abstract
An antisense oligodeoxynucleotide (ODN) complementary to the first six codons of the Bcl-2 mRNA, G3139 (oblimersen sodium; Genasense), has been shown to downregulate Bcl-2 and produce responses in a variety of malignancies including drug-resistant lymphoma. Incubation of ex vivo purified plasma cells from patients with multiple myeloma (MM) with carboxyfluorescein (FAM)-labeled antisense ODNs resulted in a time- and dose-dependent uptake in the cytoplasm and nucleus. No major differences in uptake of Bcl-2 antisense ODNs were observed among patients' samples. Incubation of purified myeloma plasma cells with G3139, but not solvent or reverse polarity control ODNs, resulted in a reduction (>75%) of Bcl-2 mRNA levels after 2 and 4 days, as measured by Real-Time PCR. Treatment with G3139 led to a sequence-specific reduction of Bcl-2 protein levels within 4 days of exposure in 10 out of 11 clinical samples from patients with chemosensitive and multidrug-resistant disease, without significant reduction of alpha-Actin, Bax, Bcl-XL, or Mcl-1 proteins. This resulted in a significantly enhanced sensitivity of the myeloma tumor cells to dexamethasone or doxorubicin-induced apoptosis. G3139 can consistently enter myeloma cells, downregulate the expression of Bcl-2, and enhance the efficacy of myeloma therapy. These data support further clinical evaluation of G3139 therapy in multiple myeloma.
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Affiliation(s)
- N W C J van de Donk
- Department of Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
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30
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Gupta D, Hideshima T, Anderson KC. Novel biologically based therapeutic strategies in myeloma. REVIEWS IN CLINICAL AND EXPERIMENTAL HEMATOLOGY 2002; 6:301-24. [PMID: 12616700 DOI: 10.1046/j.1468-0734.2002.00082.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Multiple myeloma remains incurable despite advances in conventional chemotherapy and wider applicability of high dose chemotherapy with single and/or tandem autologous peripheral blood stem cell transplantation. Although a complete remission rate of 41% and an event-free survival of 43 months have been reported after tandem transplantation, it is highly unlikely that further improvements in the outcome of multiple myeloma will be achieved by escalating cytotoxic chemotherapy alone. Novel biologically based therapies are therefore urgently required. Targeted therapeutic approaches based on: identification of genetic abnormalities in malignant plasma cells; interrupting growth of myeloma cells; triggering apoptotic signaling cascades in tumor cells; modulating growth and survival of multiple myeloma cells in the bone marrow microenvironment, i.e. angiogenesis and cytokine networks; enhancing allogeneic and autologous antimyeloma immunity; and characterizing newer myeloma antigens for serotherapy are under development. These therapies offer great promise, used alone/or in combination with conventional treatment approaches, to improve the outcome in this disease in newly diagnosed/refractory or relapsed patients with multiple myeloma.
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Affiliation(s)
- Deepak Gupta
- Jerome Lipper Myeloma Center, Department of Adult Oncology, Dana Farber Cancer Institute, and Department of Medicine, Harvard Medical School, Boston, MA, USA
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31
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Chaidos AI, Bai MC, Kamina SA, Kanavaros PE, Agnantis NJ, Bourantas KL. Incidence of apoptosis and cell proliferation in multiple myeloma: correlation with bcl-2 protein expression and serum levels of interleukin-6 (IL-6) and soluble IL-6 receptor. Eur J Haematol 2002; 69:90-4. [PMID: 12366711 DOI: 10.1034/j.1600-0609.2002.01634.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
UNLABELLED We evaluated the in vivo incidence of apoptosis and cell proliferation in multiple myeloma (MM) and investigated the correlation of both cellular events with histological tumour stage and grade, bcl-2 protein expression, serum IL-6 and sIL-6R. MATERIAL AND METHODS The TUNEL method was used to assess apoptosis and immunohistochemistry to assess the expression of proliferating cell nuclear antigen (PCNA) and bcl-2 protein in 30 bone marrow biopsy specimens. The apoptotic index (AI) and proliferative index (PI) were defined as the percentage of TUNEL and PCNA positive plasma cells, respectively. RESULTS The mean AI was 0.162% and the mean PI 27.44%. A positive correlation between AI and PI was found (r = 0.44, P = 0.017). PI was also correlated with tumour grade (P = 0.015). The mean bcl-2 protein expression was 70% and did not correlate with AI or PI, but was higher in specimens taken at first diagnosis than in specimens taken after response to treatment (P = 0.035). The mean serum IL-6 and sIL-6R values were 9.43 pg mL-1 and 47.27 ng mL-1, respectively. These parameters did not correlate with AI or PI. CONCLUSIONS The results indicate that MM might be among the malignancies with very low incidence of apoptosis. Proliferative activity increased in parallel with tumour histological grade. A positive correlation between apoptosis and proliferation was observed, but the incidence of these two cellular events seems not to be related to the bcl-2 protein expression and the serum levels of IL-6 and sIL-6R.
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Affiliation(s)
- Aristeidis I Chaidos
- Department of Haematology, University of Ioannina Medical School, 45 002 Ioannina, Greece
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32
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Abstract
A cell is a potentially dangerous thing. In unicellular organisms, cells divide and multiply in a manner that is chiefly determined by the availability of nutritional substrates. In a multicellular organism, each cell has a distinct growth potential that is designed to subsume a role in the function of the whole body. Departure from this path to one of uncontrolled cellular proliferation leads to cancer. For this reason, evolution has endowed cells with an elaborate set of systems that cause errant cells to self-destruct. This process of cell suicide is known as apoptosis or programmed cell death and it plays a crucial role in the growth of both normal and malignant cells. In this review, we describe the mechanisms whereby programmed cell death is induced and executed. In particular, we concentrate on how anti-apoptotic signals generated by cytokines promote cell survival and how these signal transduction pathways may be involved in the pathogenesis of neoplasia. Understanding how these processes contribute to tumorigenesis may suggest new therapeutic options.
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Affiliation(s)
- M K White
- Department of Pathology, Anatomy and Cell Biology, The Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA 19107, USA
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33
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Dmoszynska A, Podhorecka M, Khmaj A, Surdacka A, Walter-Croneck A, Rolinski J. Assessment of Apoptosis Regulating Factors BCL-2 and Fas Antigens on Malignant and Normal Plasma Cells. Hematology 2001; 6:255-60. [PMID: 27414844 DOI: 10.1080/10245332.2001.11746578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Multiple myeloma (MM) is characterised by slow proliferation of malignant plasma cells and their accumulation within the bone marrow. The dysregulation of programmed cell death (apoptosis) is a very important mechanism in the pathogenesis of this tumour. It prompted us to investigate the apoptosis regulating factors such as the pro-apoptotic Fas antigen and the anti-apoptotic protein BCL-2 on bone marrow malignant plasma cells in untreated patients with newly diagnosed MM and to compare them with their normal counterparts-plasma cells isolated from bone marrow of healthy individuals. Twenty-nine MM patients and 16 healthy persons were studied. Bone marrow mononuclear cells were isolated, indicated by monoclonal antibodies and analysed using the flow cytometry method. There was no statistically significant difference in BCL-2 expression in plasma cells between patients and control groups. However the percentage of BCL-2 positive cells was significantly related to the clinical stage of the disease. We detected statistically significant lower percentage of Fas positive cells in the patient group than in control. We concluded that in MM at diagnosis the expression of BCL-2 in bone marrow malignant plasma cells was comparable to normal plasma cells but expression of Fas antigen on these cells was lower. It suggests that down regulation of Fas and normal regulation of BCL-2 may be implicated for myeloma cell survival and their escape from apoptosis in vivo.
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Affiliation(s)
- A Dmoszynska
- a Department of Haematology , University School of Medicine , Jaczewskiego 8, 20-950 , Lublin , Poland
| | - M Podhorecka
- b Department of Clinical Immunology , University School of Medicine , Lublin , Poland
| | - A Khmaj
- a Department of Haematology , University School of Medicine , Jaczewskiego 8, 20-950 , Lublin , Poland
| | - A Surdacka
- a Department of Haematology , University School of Medicine , Jaczewskiego 8, 20-950 , Lublin , Poland
| | - A Walter-Croneck
- b Department of Clinical Immunology , University School of Medicine , Lublin , Poland
| | - J Rolinski
- a Department of Haematology , University School of Medicine , Jaczewskiego 8, 20-950 , Lublin , Poland
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Zandecki M, Geneviève F, Jego P, Grosbois B. [Monoclonal gammopathies of undetermined significance]. Rev Med Interne 2000; 21:1060-74. [PMID: 11191674 DOI: 10.1016/s0248-8663(00)00267-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Monoclonal gammopathy of undetermined significance is an asymptomatic disorder associated with serum monoclonal immunoglobulin spike. Its incidence is about 1% in patients of 50 years of age, and rapidly increases in elderly patients. CURRENT KNOWLEDGE AND KEY POINTS Within the 20 years following diagnosis, about 25% of patients will evolve towards either multiple myeloma (for patients with IgG or IgA) or malignant lymphoproliferative disorder (for patients with IgM). Definition, circumstances associated with a transient monoclonal spike, and currently available parameters used for differential diagnosis with either multiple myeloma or malignant lymphoproliferative disorder are successively discussed. One part of the most usual biological parameters is of prognostic value, and is reviewed in more detail. Recent data concerning immunophenotype, cytogenetics and molecular biology of plasma cells reinforce the link between the asymptomatic condition and multiple myeloma. In monoclonal gammopathy of undetermined significance, some plasma cells resemble normal or reactive plasma cells, whereas others mimic those found in multiple myeloma. FUTURE PROSPECTS AND PROJECTS The most recent biological data are also discussed in order to evaluate whether some would help to discriminate those patients who will remain asymptomatic lifelong from those who will evolve towards multiple myeloma.
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Affiliation(s)
- M Zandecki
- Laboratoire d'hématologie, centre hospitalier universitaire, 4, rue Larrey, 49033 Angers, France.
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Jourdan M, De Vos J, Mechti N, Klein B. Regulation of Bcl-2-family proteins in myeloma cells by three myeloma survival factors: interleukin-6, interferon-alpha and insulin-like growth factor 1. Cell Death Differ 2000; 7:1244-52. [PMID: 11175262 PMCID: PMC2423422 DOI: 10.1038/sj.cdd.4400758] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
As survival regulation is a key process in multiple myeloma biology, we have studied the Bcl-2 family proteins that can be regulated by three myeloma cell survival factors: interleukin-6 (IL-6), interferon-alpha (IFN-alpha) and insulin-like growth factor (IGF-1). Eleven myeloma cell lines, whose survival and proliferation are dependent on addition of IL-6, variably expressed 10 anti-apoptotic or pro-apoptotic proteins of the Bcl-2-family. When myeloma cells from four cell lines were IL-6 starved and activated with IL-6 or IFN-alpha, we observed that only Mcl-1 expression was up-regulated with myeloma cell survival induction. Nor was obvious regulation of these 10 pro-apoptotic or anti-apoptotic proteins found with IGF-1, another potent myeloma cell survival factor. Our results indicate that the myeloma cell survival activity of IL-6 linked to Bcl-xL regulation cannot be generalized and emphasize that Mcl-1 is the main target of IL-6 and IFN-alpha stimulation. However, other changes in the activity of the Bcl-2 protein family or other apoptosis regulators must be identified to elucidate the IGF-1 action mechanism. Cell Death and Differentiation (2000) 7, 1244 - 1252.
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Affiliation(s)
| | | | | | - Bernard Klein
- * Correspondence should be adressed to: Bernard Klein
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Kastrinakis NG, Gorgoulis VG, Foukas PG, Dimopoulos MA, Kittas C. Molecular aspects of multiple myeloma. Ann Oncol 2000; 11:1217-28. [PMID: 11106109 DOI: 10.1023/a:1008331714186] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Multiple myeloma (MM) is a B-cell neoplasm characterized by bone marrow infiltration with malignant plasma cells, which synthesize and secrete monoclonal immunoglobulin (Ig) fragments. Despite the considerable progress in the understanding of MM biology, the molecular basis of the disease remains elusive. The initial transformation is thought to occur in a postgerminal center B-lineage cell, carrying a somatically hypermutated Ig heavy chain (IGH) gene. This plasmablastic precursor cell colonizes the bone marrow, propagates clonally and differentiates into a slowly proliferating myeloma cell population, all under the influence of specific cell adhesion molecules and cytokines. Production of interleukin-6 by stromal cells, osteoblasts and, in some cases, neoplastic cells is an essential element of myeloma cell growth, with the cytokine stimulus being delivered intracellularly via the Jack-STAT and ras signaling pathways. While karyotypic changes have been identified in up to 50% of MM patients, recent molecular cytogenetic techniques have revealed chromosomal abnormalities in the vast majority of examined cases. Translocations mostly involve illegal switch rearrangements of the IGH locus with various partner genes (CCND1, FGFR3, c-maf). Such events have been assigned a critical role in MM development. Mutations in coding and regulatory regions, as well as aberrant expression patterns of several oncogenes (c-myc, ras) and tumor suppressor genes (p16, p15) have been reported. Key regulators of programmed cell death (BCL-2, Fas), tumor expansion (metalloproteinases) and drug responsiveness (topoisomerase II alpha) have also been implicated in the pathogenesis of this hematologic malignancy. A tumorigenic role for human herpesvirus 8 (HHV8) was postulated recently, following the detection of viral sequences in bone marrow dendritic cells of MM patients. However, since several research groups were unable to confirm this observation, the role of HHV8 remains unclear. Translation of the advances in MM molecular biology into novel therapeutic strategies is essential in order to improve disease prognosis.
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Affiliation(s)
- N G Kastrinakis
- Department of Histology, School of Medicine, University of Athens, Greece
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Katunuma N, Matsui A, Utsumi K, Qang LT, Ohashi A. A novel procaspase-3 activating cascade in liver lysosomes, and lack of the cascade in hepatoma cells. ADVANCES IN ENZYME REGULATION 2000; 40:427-38. [PMID: 10828361 DOI: 10.1016/s0065-2571(99)00058-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- N Katunuma
- Institute for Health Sciences, Tokushima Bunri University, 770-8514, Tokushima, Japan
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Marschitz I, Tinhofer I, Hittmair A, Egle A, Kos M, Greil R. Analysis of Bcl-2 protein expression in chronic lymphocytic leukemia. A comparison of three semiquantitation techniques. Am J Clin Pathol 2000; 113:219-29. [PMID: 10664624 DOI: 10.1309/491w-l1tn-ufqx-t61b] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
A number of studies revealed that high expression of the proto-oncogene bcl-2 correlated with poor prognosis or resistance to chemotherapy in some tumors but predicted a favorable clinical course in other neoplasias. In these studies, however, different immunologic techniques for Bcl-2 detection were used, raising the question of whether the methods applied were comparable. Using chronic lymphocytic leukemia (CLL) cells, the aims of our study were as follows: (1) to determine the reproducibility of Bcl-2 semiquantitation by immunocytochemistry, flow cytometry, or immunoblotting; (2) to study the agreement between results obtained by these methods; and (3) to examine the association between Bcl-2 expression in tumor cells of 99 patients with CLL and clinical parameters. We found that determination of Bcl-2 expression by immunocytochemistry was reproducible and the results were comparable with those of flow cytometry and immunoblotting. In the patient collective examined, Bcl-2 expression did not reflect the extent of tumor mass, but higher levels were found more often in patients with progressive disease.
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Affiliation(s)
- I Marschitz
- Department of Internal Medicine, University of Innsbruck, Austria
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