51
|
Chrysis D, Zaman F, Chagin AS, Takigawa M, Sävendahl L. Dexamethasone induces apoptosis in proliferative chondrocytes through activation of caspases and suppression of the Akt-phosphatidylinositol 3'-kinase signaling pathway. Endocrinology 2005; 146:1391-7. [PMID: 15576458 DOI: 10.1210/en.2004-1152] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although glucocorticoids are known to induce apoptosis in chondrocytes, the mechanisms for this effect and the potential antiapoptotic role of IGF-I are unknown. To address this, we studied the effects of dexamethasone (Dexa) on apoptosis in the HCS-2/8 chondrocytic cell line. Dexa (25 microm) increased apoptosis (cell death ELISA) by 39% and 45% after 48 and 72 h, respectively (P < 0.01 and P < 0.05, respectively). IGF-I (100 ng/ml) decreased Dexa-induced apoptosis to levels similar to control cells. Apoptosis was associated with cleavage of poly-ADP-ribose polymerase (PARP) and alpha-fodrin and activation of caspases-8, -9, and -3 (Western), an effect that was counteracted when chondrocytes were cocultured with Dexa + IGF-I. Inhibitors for caspases-8, -9, and -3 (50 microm each) equally suppressed Dexa-induced apoptosis (P < 0.01). Time-response experiments showed that caspase-8 was activated earlier (at 12 h) than caspase-9 (at 36 h). We studied the phosphatidylinositol 3'-kinase (PI3K) pathway to further investigate the mechanisms of Dexa-induced apoptosis. Dexa decreased Akt phosphorylation by 93% (P < 0.001) without affecting total Akt and increased the p85alpha subunit 4-fold. The Akt inhibitor SH-6 (10 microm) increased apoptosis by 54% (P < 0.001). When combining Dexa with SH-6, apoptosis was not further increased, showing that Dexa-induced apoptosis is mediated through inhibition of the PI3K pathway. Addition of IGF-I to SH-6- or Dexa + SH-6-treated cells decreased apoptosis by 21.2% (P < 0.001) and 20.6% (P < 0.001), respectively. We conclude that Dexa-induced apoptosis is caspase dependent with an early activation of caspase-8. IGF-I can rescue chondrocytes from Dexa-induced apoptosis partially through the activation of other pathways than the PI3K signaling pathway. Based on our in vitro data, we speculate that in vivo treatment with glucocorticoids may diminish longitudinal growth by increasing apoptosis of proliferative growth plate chondrocytes.
Collapse
Affiliation(s)
- Dionisios Chrysis
- Department of Woman and Child Health, Pediatric Endocrinology Unit, Astrid Lindgren Childrens Hospital, Karolinska Institutet, SE-17176 Stockholm, Sweden.
| | | | | | | | | |
Collapse
|
52
|
Zhao Z, Leister WH, Robinson RG, Barnett SF, Defeo-Jones D, Jones RE, Hartman GD, Huff JR, Huber HE, Duggan ME, Lindsley CW. Discovery of 2,3,5-trisubstituted pyridine derivatives as potent Akt1 and Akt2 dual inhibitors. Bioorg Med Chem Lett 2005; 15:905-9. [PMID: 15686884 DOI: 10.1016/j.bmcl.2004.12.062] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Revised: 12/16/2004] [Accepted: 12/21/2004] [Indexed: 10/25/2022]
Abstract
This letter describes the discovery of a novel series of dual Akt1/Akt2 kinase inhibitors, based on a 2,3,5-trisubstituted pyridine scaffold. Compounds from this series, which contain a 5-tetrazolyl moiety, exhibit more potent inhibition of Akt2 than Akt1.
Collapse
Affiliation(s)
- Zhijian Zhao
- Department of Medicinal Chemistry, Technology Enabled Synthesis Group, Merck Research Laboratories, Merck & Co., PO Box 4, West Point, PA 19486, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
53
|
Lindsley CW, Zhao Z, Leister WH, Robinson RG, Barnett SF, Defeo-Jones D, Jones RE, Hartman GD, Huff JR, Huber HE, Duggan ME. Allosteric Akt (PKB) inhibitors: discovery and SAR of isozyme selective inhibitors. Bioorg Med Chem Lett 2005; 15:761-4. [PMID: 15664853 DOI: 10.1016/j.bmcl.2004.11.011] [Citation(s) in RCA: 379] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2004] [Revised: 11/02/2004] [Accepted: 11/02/2004] [Indexed: 10/26/2022]
Abstract
This letter describes the development of two series of potent and selective allosteric Akt kinase inhibitors that display an unprecedented level of selectivity for either Akt1, Akt2 or both Akt1/Akt2. An iterative analog library synthesis approach quickly provided a highly selective Akt1/Akt2 inhibitor that induces apoptosis in tumor cells and inhibits Akt phosphorylation in vivo.
Collapse
Affiliation(s)
- Craig W Lindsley
- Department of Medicinal Chemistry, Technology Enabled Synthesis Group, Merck Research Laboratories, Merck and Co., PO Box 4, West Point, PA 19486, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
54
|
Lentzsch S, Chatterjee M, Gries M, Bommert K, Gollasch H, Dörken B, Bargou RC. PI3-K/AKT/FKHR and MAPK signaling cascades are redundantly stimulated by a variety of cytokines and contribute independently to proliferation and survival of multiple myeloma cells. Leukemia 2004; 18:1883-90. [PMID: 15356648 DOI: 10.1038/sj.leu.2403486] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
IL-6 has been reported to play a central role in growth and survival of multiple myeloma (MM) cells. However, recently we have demonstrated that in the presence of bone marrow stromal cells, survival of MM cells becomes independent of the IL-6/gp130/STAT3 pathway questioning the singular role of IL-6 in MM. Therefore, it was the aim of this study to identify additional factors and signaling pathways that might contribute to the growth and survival of MM cells. We found that in addition to IL-6 a number of bone marrow derived cytokines such as LIF, VEGF, bFGF, MIP-1alpha, SDF-1alpha, IL-1beta, SCF and IL-3 activate the MAPK pathway and induce proliferation of MM.1S and RPMI-8226 MM cells. In addition, these cytokines independently phosphorylate the forkhead family member FKHR via PI3-K/AKT and support survival of primary human MM cells. Inhibition of these pathways induces apoptosis in MM cell lines and primary MM cells. Thus, we provide evidence that in addition to IL-6 a number of different factors trigger important growth-promoting pathways to support the proliferation and survival of MM cells. Therefore, blocking such pathways, rather than blocking a single factor, might be a promising approach for the development of novel treatment strategies in MM.
Collapse
Affiliation(s)
- S Lentzsch
- Department of Hematology, Oncology and Tumor immunology, Robert Rössle Cancer Clinic and HELIOS Clinics at the Max Delbrück Center for Molecular Medicine, Humboldt University, Charité, Campus Buch, Berlin, Germany
| | | | | | | | | | | | | |
Collapse
|
55
|
Hsu JH, Shi Y, Frost P, Yan H, Hoang B, Sharma S, Gera J, Lichtenstein A. Interleukin-6 activates phosphoinositol-3' kinase in multiple myeloma tumor cells by signaling through RAS-dependent and, separately, through p85-dependent pathways. Oncogene 2004; 23:3368-75. [PMID: 15021914 DOI: 10.1038/sj.onc.1207459] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The IL-6-induced activation of the phosphatidylinositol-3' kinase (PI3-K)/AKT cascade in multiple myeloma (MM) cells is critical for tumor cell proliferation and viability. Since the IL-6 receptor does not contain binding sites for the p85 regulatory portion of PI3-K, intermediate molecules must play a role. Coimmunoprecipitation studies in MM cell lines demonstrated the IL-6-induced formation of two independent PI3-K-containing complexes: one containing p21 RAS but not STAT-3 and a second containing STAT-3 but not RAS. Both complexes demonstrated IL-6-induced lipid kinase activity. IL-6 also generated kinase activity in a mutant p110 molecule that could not bind p85. Use of dominant-negative (DN) constructs confirmed the presence of two independent pathways of activation: a DN RAS prevented the IL-6-induced generation of lipid kinase activity in the mutant p110 molecule but had no effect on activity generated in the STAT-3-containing complex. In contrast, a DN p85 prevented the generation of kinase activity in the STAT-3-containing complex but had no effect on activity generated in the p110 molecule. Both DN constructs significantly prevented the IL-6-induced activation of AKT. MM cells expressing activating RAS mutations demonstrated enhanced IL-6-independent growth and constitutive PI3-K activity. These data indicate two potential independent pathways of PI3-K/AKT activation in MM cells: one mediated via signaling through RAS which is independent of p85 and a second mediated via p85 and due to a STAT-3-containing complex.
Collapse
Affiliation(s)
- Jung-Hsin Hsu
- Department of Medicine, West LA VA-UCLA Medical Center and Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90073, USA
| | | | | | | | | | | | | | | |
Collapse
|
56
|
Chatterjee M, Stühmer T, Herrmann P, Bommert K, Dörken B, Bargou RC. Combined disruption of both the MEK/ERK and the IL-6R/STAT3 pathways is required to induce apoptosis of multiple myeloma cells in the presence of bone marrow stromal cells. Blood 2004; 104:3712-21. [PMID: 15297310 DOI: 10.1182/blood-2004-04-1670] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The interleukin-6 receptor (IL-6R)/signal transducer and activator of transcription 3 (STAT3) pathway contributes to the pathogenesis of multiple myeloma (MM) and protects MM cells from apoptosis. However, MM cells survive the IL-6R blockade if they are cocultured with bone marrow stromal cells (BMSCs), suggesting that the BM microenvironment stimulates IL-6-independent pathways that exert a pro-survival effect. The goal of this study was to investigate the underlying mechanism. Detailed pathway analysis revealed that BMSCs stimulate STAT3 via the IL-6R, and mitogen-activated protein (MAP) kinases via IL-6R-independent mechanisms. Abolition of MEK1,2 activity with PD98059, or ERK1,2 small interfering RNA knockdown, was insufficient to induce apoptosis. However, the combined disruption of the IL-6R/STAT3 and MEK1,2/ERK1,2 pathways led to strong induction of apoptosis even in the presence of BMSCs. This effect was observed with MM cell lines and with primary MM cells, suggesting that the BMSC-induced activation of MEK1,2/ERK1,2 renders MM cells IL-6R/STAT3 independent. Therefore, in the presence of cells from the BM micro-environment, combined targeting of different (and independently activated) pathways is required to efficiently induce apoptosis of MM cells. This might have direct implications for the development of future therapeutic strategies for MM.
Collapse
Affiliation(s)
- Manik Chatterjee
- Department of Hematology, Oncology, and Tumorimmunology, Robert Rössle Cancer Clinic and HELIOS-Clinics at the Max Delbrück Center for Molecular Medicine, Charité, Humboldt University, Campus Berlin-Buch, Lindenberger Weg 80, 13122 Berlin, Germany
| | | | | | | | | | | |
Collapse
|
57
|
Osadchy A, Drucker L, Radnay J, Shapira H, Lishner M. Microenvironment factors do not afford myeloma cell lines protection from simvastatin. Eur J Haematol 2004; 73:183-90. [PMID: 15287916 DOI: 10.1111/j.1600-0609.2004.00284.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The intensive interactions of myeloma cells (multiple myeloma, MM) with microenvironmental components of the bone marrow contribute significantly to their proliferation and survival. It has been shown that these signals confer drug resistance, delineating their circumvention as a primary objective in disease treatment. This study was designed to assess the effect of some major extracellular factors on the previously established anti-neoplastic response of myeloma cells to simvastatin (Sim). STUDY DESIGN RPMI8226, U266, and ARH77 seeded in culture plates precoated with fibronectin (FN)/agarose/none were treated with Sim, insulin-like growth factor-I (IGF-I), interleukin-6 (IL-6) or combinations for 5 d. Then we assessed cell morphology, viability (WST1), cell cycle (propidium iodide, PI, staining and flow cytometric analysis), total cell count, and cell death (trypan blue exclusion), and DNA fragmentation. RESULTS AND CONCLUSIONS Reduced viability was demonstrated with Sim in all treated cell lines with and without co-administration of IGF-I or IL-6 (P < 0.05). The extent of inhibition did not vary between Sim only and combinations (NS). FN did not influence cell response to Sim alone or combined with IL-6/IGF-I (NS). We conclude that IL-6, IGF-I, and FN do not afford myeloma cell lines protection from Sim modulation.
Collapse
Affiliation(s)
- Alla Osadchy
- Oncogenetic Laboratory, Sapir Medical Center, Meir Hospital, Kfar Sava, Israel
| | | | | | | | | |
Collapse
|
58
|
Panwalkar A, Verstovsek S, Giles FJ. Mammalian target of rapamycin inhibition as therapy for hematologic malignancies. Cancer 2004; 100:657-66. [PMID: 14770419 DOI: 10.1002/cncr.20026] [Citation(s) in RCA: 172] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mammalian target of rapamycin (mTOR) is a downstream effector of the phosphatidylinositol 3-kinase (PI3K)/Akt (protein kinase B) signaling pathway, which mediates cell survival and proliferation. mTOR regulates essential signal-transduction pathways, is involved in the coupling of growth stimuli with cell cycle progression, and initiates mRNA translation in response to favorable nutrient environments. mTOR is involved in regulating many aspects of cell growth, including membrane traffic, protein degradation, protein kinase C signaling, ribosome biogenesis, and transcription. Because mTOR activates both the 40S ribosomal protein S6 kinase (p70s6k) and the eukaryotic initiation factor 4E-binding protein 1, its inhibitors cause G1-phase cell cycle arrest. Inhibitors of mTOR also prevent cyclin dependent kinase (CDK) activation, inhibit retinoblastoma protein phosphorylation, and accelerate the turnover of cyclin D1, leading to a deficiency of active CDK4/cyclin D1 complexes, all of which may help cause G1-phase arrest. It is known that the phosphatase and tensin homologue tumor suppressor gene (PTEN) plays a major role in embryonic development, cell migration, and apoptosis. Malignancies with PTEN mutations, which are associated with constitutive activation of the PI3K/Akt pathway, are relatively resistant to apoptosis and may be particularly sensitive to mTOR inhibitors. Rapamycin analogs with relatively favorable pharmaceutical properties, including CCI-779, RAD001, and AP23573, are under investigation in patients with hematologic malignancies.
Collapse
Affiliation(s)
- Amit Panwalkar
- Section of Developmental Therapeutics, Department of Leukemia, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
| | | | | |
Collapse
|
59
|
Brocke-Heidrich K, Kretzschmar AK, Pfeifer G, Henze C, Löffler D, Koczan D, Thiesen HJ, Burger R, Gramatzki M, Horn F. Interleukin-6-dependent gene expression profiles in multiple myeloma INA-6 cells reveal a Bcl-2 family-independent survival pathway closely associated with Stat3 activation. Blood 2004; 103:242-51. [PMID: 12969979 DOI: 10.1182/blood-2003-04-1048] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Interleukin 6 (IL-6) is a growth and survival factor for multiple myeloma cells. As we report here, the IL-6-dependent human myeloma cell line INA-6 responds with a remarkably rapid and complete apoptosis to cytokine withdrawal. Among the antiapoptotic members of the B-cell lymphoma-2 (Bcl-2) family of apoptosis regulators, only myeloid cell factor-1 (Mcl-1) was slightly induced by IL-6. Overexpression studies demonstrated, however, that IL-6 does not exert its survival effect primarily through this pathway. The IL-6 signal transduction pathways required for survival and the target genes controlled by them were analyzed by using mutated receptor chimeras. The activation of signal transducer and activator of transcription 3 (Stat3) turned out to be obligatory for the survival of INA-6 cells. The same held true for survival and growth of XG-1 myeloma cells. Gene expression profiling of INA-6 cells by using oligonucleotide microarrays revealed many novel IL-6 target genes, among them several genes coding for transcriptional regulators involved in B-lymphocyte differentiation as well as for growth factors and receptors potentially implicated in autocrine or paracrine growth control. Regulation of most IL-6 target genes required the activation of Stat3, underscoring its central role for IL-6 signal transduction. Taken together, our data provide evidence for the existence of an as yet unknown Stat3-dependent survival pathway in myeloma cells.
Collapse
Affiliation(s)
- Katja Brocke-Heidrich
- Institute of Clinical Immunology and Transfusion Medicine, University Hospital Leipzig, Johannisallee 30, 04103 Leipzig, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
60
|
Moreaux J, Legouffe E, Jourdan E, Quittet P, Rème T, Lugagne C, Moine P, Rossi JF, Klein B, Tarte K. BAFF and APRIL protect myeloma cells from apoptosis induced by interleukin 6 deprivation and dexamethasone. Blood 2003; 103:3148-57. [PMID: 15070697 PMCID: PMC2387243 DOI: 10.1182/blood-2003-06-1984] [Citation(s) in RCA: 392] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Identification of growth factors in neoplasias may be a target for future therapies by blocking either growth factor receptor interaction or the induced pathway. Using gene expression profiling, we identified overexpression of 2 receptors for a proliferation-inducing ligand (APRIL) and B-cell activating factor (BAFF) in malignant plasma cells compared with normal plasma cells. APRIL and BAFF are involved in a variety of tumor and autoimmune diseases, including B-cell malignancies. We confirmed the expression of BAFF and APRIL receptors (B-cell maturation antigen [BCMA], transmembrane activator and calcium modulator and cyclophilin ligand interactor [TACI], and BAFF-R) in a majority of 13 myeloma cell lines and in the purified primary myeloma cells of 11 patients. APRIL and BAFF were potent survival factors for exogenous cytokine-dependent myeloma cell lines and were autocrine growth factors for the RPMI8226 and L363 autonomously growing cell lines. These factors activated nuclear factor (NF)-kappaB, phosphatidylinositol-3 (PI-3) kinase/AKT, and mitogen-activated protein kinase (MAPK) kinase pathways and induced a strong up-regulation of the Mcl-1 and Bcl-2 antiapoptotic proteins in myeloma cells. BAFF or APRIL was also involved in the survival of primary myeloma cells cultured with their bone-marrow environment, and protected them from dexamethasone (DEX)-induced apoptosis. Finally, the serum levels of BAFF and APRIL were increased about 5-fold in patients with multiple myeloma (MM) as compared with healthy donors. Altogether, these data suggest that APRIL/BAFF inhibitors may be of clinical value in MM.
Collapse
Affiliation(s)
- Jérôme Moreaux
- Immunopathologie des maladies tumorales et autoimmunes
INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm
99, Rue Puech Villa
34197 MONTPELLIER CEDEX 5,FR
| | - Eric Legouffe
- Clinical Hematology Department
CHRU MontpellierMontpellier 34000,FR
| | - Eric Jourdan
- Service de médecine interne B
CHU Nîmes30900 Nîmes,FR
| | - Philippe Quittet
- Clinical Hematology Department
CHRU MontpellierMontpellier 34000,FR
| | - Thierry Rème
- Immunopathologie des maladies tumorales et autoimmunes
INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm
99, Rue Puech Villa
34197 MONTPELLIER CEDEX 5,FR
| | - Cécile Lugagne
- Immunopathologie des maladies tumorales et autoimmunes
INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm
99, Rue Puech Villa
34197 MONTPELLIER CEDEX 5,FR
| | - Philippe Moine
- Immunopathologie des maladies tumorales et autoimmunes
INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm
99, Rue Puech Villa
34197 MONTPELLIER CEDEX 5,FR
| | | | - Bernard Klein
- Immunopathologie des maladies tumorales et autoimmunes
INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm
99, Rue Puech Villa
34197 MONTPELLIER CEDEX 5,FR
- * Correspondence should be adressed to: Bernard Klein
| | - Karin Tarte
- Immunopathologie des maladies tumorales et autoimmunes
INSERM : U475IFR76Institut de recherche en biothérapieUniversité Montpellier ICentre de Recherche Inserm
99, Rue Puech Villa
34197 MONTPELLIER CEDEX 5,FR
| |
Collapse
|
61
|
Zhang J, Choi Y, Mavromatis B, Lichtenstein A, Li W. Preferential killing of PTEN-null myelomas by PI3K inhibitors through Akt pathway. Oncogene 2003; 22:6289-95. [PMID: 13679867 DOI: 10.1038/sj.onc.1206718] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We recently reported that internal deletion of PTEN tumor suppressor gene in OPM2 and Delta47 myeloma lines led to high Akt activation. Re-expression of PTEN induced strong apoptosis and growth inhibition. To understand the biologic importance of the phosphatidylinositol 3 kinase (PI3K)/Akt activation affected by PTEN deletion, we analysed apoptosis and growth inhibition by applying PI3K inhibitors to myeloma lines and by expressing Akt constructs. The PI3K inhibitors preferentially suppressed PTEN-null myeloma growth to those expressing PTEN, indicating that PI3K activation is more critical for growth and survival of those lines with PTEN mutations than others expressing a functional PTEN gene. Since PTEN-null myeloma lines exhibited much stronger Akt activation than PTEN-expressing cells in response to insulin-like growth factor I stimulation, we determined whether Akt could be responsible for PI3K-mediated cell survival and growth of PTEN-null myeloma lines. Expression of an active Akt, but not its kinase dead mutant, reversed wortmannin- and dexamethasone-induced apoptosis and growth inhibition in PTEN-null myeloma lines, suggesting that Akt lies downstream of PI3K for PTEN-null myeloma survival and dexamethasone resistance. In summary, we have provided evidence that PTEN-null myeloma cells are stringently dependent on the PI3K/Akt activation for cell survival. These results may provide a basis to treat myeloma patients with PI3K and Akt inhibitors.
Collapse
Affiliation(s)
- Jie Zhang
- Lombardi Cancer Center, Georgetown University Medical School, Washington, DC 20057-1469, USA
| | | | | | | | | |
Collapse
|
62
|
Abstract
The IL (interleukin)-6-type cytokines IL-6, IL-11, LIF (leukaemia inhibitory factor), OSM (oncostatin M), ciliary neurotrophic factor, cardiotrophin-1 and cardiotrophin-like cytokine are an important family of mediators involved in the regulation of the acute-phase response to injury and infection. Besides their functions in inflammation and the immune response, these cytokines play also a crucial role in haematopoiesis, liver and neuronal regeneration, embryonal development and fertility. Dysregulation of IL-6-type cytokine signalling contributes to the onset and maintenance of several diseases, such as rheumatoid arthritis, inflammatory bowel disease, osteoporosis, multiple sclerosis and various types of cancer (e.g. multiple myeloma and prostate cancer). IL-6-type cytokines exert their action via the signal transducers gp (glycoprotein) 130, LIF receptor and OSM receptor leading to the activation of the JAK/STAT (Janus kinase/signal transducer and activator of transcription) and MAPK (mitogen-activated protein kinase) cascades. This review focuses on recent progress in the understanding of the molecular mechanisms of IL-6-type cytokine signal transduction. Emphasis is put on the termination and modulation of the JAK/STAT signalling pathway mediated by tyrosine phosphatases, the SOCS (suppressor of cytokine signalling) feedback inhibitors and PIAS (protein inhibitor of activated STAT) proteins. Also the cross-talk between the JAK/STAT pathway with other signalling cascades is discussed.
Collapse
|
63
|
Heinrich PC, Behrmann I, Haan S, Hermanns HM, Müller-Newen G, Schaper F. Principles of interleukin (IL)-6-type cytokine signalling and its regulation. Biochem J 2003; 374:1-20. [PMID: 12773095 PMCID: PMC1223585 DOI: 10.1042/bj20030407] [Citation(s) in RCA: 2309] [Impact Index Per Article: 110.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2003] [Revised: 04/30/2003] [Accepted: 05/29/2003] [Indexed: 12/11/2022]
Abstract
The IL (interleukin)-6-type cytokines IL-6, IL-11, LIF (leukaemia inhibitory factor), OSM (oncostatin M), ciliary neurotrophic factor, cardiotrophin-1 and cardiotrophin-like cytokine are an important family of mediators involved in the regulation of the acute-phase response to injury and infection. Besides their functions in inflammation and the immune response, these cytokines play also a crucial role in haematopoiesis, liver and neuronal regeneration, embryonal development and fertility. Dysregulation of IL-6-type cytokine signalling contributes to the onset and maintenance of several diseases, such as rheumatoid arthritis, inflammatory bowel disease, osteoporosis, multiple sclerosis and various types of cancer (e.g. multiple myeloma and prostate cancer). IL-6-type cytokines exert their action via the signal transducers gp (glycoprotein) 130, LIF receptor and OSM receptor leading to the activation of the JAK/STAT (Janus kinase/signal transducer and activator of transcription) and MAPK (mitogen-activated protein kinase) cascades. This review focuses on recent progress in the understanding of the molecular mechanisms of IL-6-type cytokine signal transduction. Emphasis is put on the termination and modulation of the JAK/STAT signalling pathway mediated by tyrosine phosphatases, the SOCS (suppressor of cytokine signalling) feedback inhibitors and PIAS (protein inhibitor of activated STAT) proteins. Also the cross-talk between the JAK/STAT pathway with other signalling cascades is discussed.
Collapse
Affiliation(s)
- Peter C Heinrich
- Institut für Biochemie, RWTH Aachen, Universitätsklinikum, Pauwelsstrasse 30, D-52074 Aachen, Germany.
| | | | | | | | | | | |
Collapse
|
64
|
Klein B, Tarte K, Jourdan M, Mathouk K, Moreaux J, Jourdan E, Legouffe E, De Vos J, Rossi JF. Survival and proliferation factors of normal and malignant plasma cells. Int J Hematol 2003; 78:106-13. [PMID: 12953803 PMCID: PMC2423421 DOI: 10.1007/bf02983377] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Since the first identification of interleukin (IL)-6 as a myeloma cell growth factor by Dr. Kawano's and Dr. Klein's groups 14 years ago, numerous studies have emphasized its major roles in the emergence of malignant plasma cells in vivo and in the generation of normal plasma cells. Four transcription factors control B-cell differentiation into plasma cells. The B-cell transcription factor pax-5 is mainly responsible for a B-cell phenotype, and bcl-6 represses the plasma cell transcription factor blimp-1 and plasma cell differentiation. bcl-6 expression is triggered by CD40 and IL-4 activation. A lack of CD40 and IL-4 activation yields a down-regulation of bcl-6 expression, and IL-6 stimulation yields an up-regulation of blimp-1, mainly through STAT3 activation. Blimp-1 further down-regulates bcl-6 and pax-5 expression and makes plasma cell differentiation possible. IL-6 as well as IL-10 up-regulate XBP-1. XBP-1 is another transcription factor that is involved in plasma cell differentiation and whose gene expression is shut down by pax-5. The plasma cell transcription factors blimp-1 and XBP-1 are up-regulated, and the B-cell transcription factors bcl-6 and pax-5 are down-regulated, in malignant cells compared to B-cells. Apart from the recent identification of these 4 transcription factors, the factors involved in normal plasma cell generation are mostly unknown. Regarding malignant plasma cells, 3 categories of growth factors have been identified: (1) the IL-6 family cytokines, IL-10, and interferon alpha that activate the Janus kinase-signal transducer and activator of transcription (JAK/STAT) and mitogen-activated protein (MAP) kinase pathways; (2) growth factors activating the phosphatidylinositol (PI)-3 kinase/AKT and MAP kinase pathways, unlike the JAK/STAT pathway (insulin-like growth factor 1, hepatocyte growth factor, and members of the epidermal growth factor family able to bind syndecan-1 proteoglycan); and (3) B-cell-activating factor (BAFF) or proliferation-inducing ligand (APRIL) that activate the nuclear factor KB and PI-3 kinase/AKT pathways. BAFF and APRIL bind to BAFF receptor and TACI and are major B-cell survival factors. Recent data indicate that these various growth factors may cooperate to provide optimum signaling because they are localized together and with cytoplasmic transduction elements in caveolinlinked membrane caveolae. The identification of these myeloma cell growth factors and of the associated transduction pathways should provide novel therapeutic targets in multiple myeloma.
Collapse
Affiliation(s)
- Bernard Klein
- INSERM U475 and Unit for Cellular and Gene Therapy, CHU Montpellier, Montpellier, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
65
|
Hu L, Shi Y, Hsu JH, Gera J, Van Ness B, Lichtenstein A. Downstream effectors of oncogenic ras in multiple myeloma cells. Blood 2003; 101:3126-35. [PMID: 12515720 DOI: 10.1182/blood-2002-08-2640] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ectopic expression of mutated K-ras or N-ras in the interleukin 6 (IL-6)-dependent ANBL6 multiple myeloma cell line induces cytokine-independent growth. To investigate the signaling pathways activated by oncogenic ras that may stimulate IL-6-independent growth, we compared ANBL6 cells stably transfected with mutated K or N-ras genes with wild-type ras-expressing control cells identically transfected with an empty vector. Upon depletion of IL-6, both mutated ras-containing myeloma lines demonstrated constitutive activation of mitogen-activated extracellular kinase 2(MEK)/extracellular signal-regulated kinase (ERK), phosphatidylinositol-3 kinase (PI3-kinase)/AKT, mammalian target of rapamycin (mTOR)/p70S6-kinase, and nuclear factor kappa B (NF-kappa B) pathways. In contrast, signal transducer and activator of transcription-3 (STAT-3) was not constitutively tyrosine phosphorylated in mutant ras-expressing cells. We used several maneuvers in attempts to selectively target these constitutively active pathways. The mTOR inhibitors rapamycin and CCI-779, the PI3-kinase inhibitor LY294002, and the MEK inhibitor PD98059 all significantly curtailed growth of mutant ras-containing cells. Farnesyl transferase inhibitors, used to target ras itself, had modest effects only against mutant N-ras-containing cells. Growth of mutant N-ras-containing myeloma cells was also inhibited by acute expression of the IKB superrepressor gene, which abrogated NF-kappa B activation. These results indicate that several pathways contributing to stimulation of cytokine-independent growth are activated downstream of oncogenic ras in myeloma cells. They also suggest that therapeutic strategies that target these pathways may be particularly efficacious in patients whose myeloma clones contain ras mutations.
Collapse
Affiliation(s)
- Liping Hu
- Hematology-Oncology Division, West Los Angeles Veteran's Administration-University of California Los Angeles Medical Center, Los Angeles, CA 90073, USA
| | | | | | | | | | | |
Collapse
|
66
|
Derksen PWB, de Gorter DJJ, Meijer HP, Bende RJ, van Dijk M, Lokhorst HM, Bloem AC, Spaargaren M, Pals ST. The hepatocyte growth factor/Met pathway controls proliferation and apoptosis in multiple myeloma. Leukemia 2003; 17:764-74. [PMID: 12682635 DOI: 10.1038/sj.leu.2402875] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The evolution of multiple myeloma (MM) depends on complex signals from the bone marrow (BM) microenvironment, supporting the proliferation and survival of malignant plasma cells. An interesting candidate signal is hepatocyte growth factor/scatter factor (HGF), since its receptor Met is expressed on MM cells, while HGF is produced by BM stromal cells and by some MM cell lines, enabling para- or autocrine interaction. To explore this hypothesis, we studied the biological effects of HGF stimulation on MM cell lines and on primary MMs. We observed that Met is expressed by the majority of MM cell lines and by approximately half of the primary plasma cell neoplasms tested. Stimulation of MM cells with HGF led to the activation of the RAS/mitogen-activated protein kinase and phosphatidylinositol 3-kinase/protein kinase B (PI3K/PKB) pathways, signaling routes that have been implicated in the regulation of cell proliferation and survival. Indeed, functional studies demonstrated that HGF has strong proliferative and anti-apoptotic effects on both MM cell lines and primary MM cells. Furthermore, by applying specific signal-transduction inhibitors, we demonstrated that MEK is required for HGF-induced proliferation, whereas activation of PI3K is required for both HGF-induced proliferation and for rescue of MM cells from apoptosis. Taken together, our data indicate that HGF is a potent myeloma growth and survival factor and suggest that the HGF/Met pathway is a potential therapeutic target in MM.
Collapse
Affiliation(s)
- P W B Derksen
- Department of Pathology, Academic Medical Center, University of Amsterdam, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
67
|
Di Sario A, Bendia E, Taffetani S, Marzioni M, Candelaresi C, Pigini P, Schindler U, Kleemann HW, Trozzi L, Macarri G, Benedetti A. Selective Na+/H+ exchange inhibition by cariporide reduces liver fibrosis in the rat. Hepatology 2003; 37:256-66. [PMID: 12540775 DOI: 10.1053/jhep.2003.50028] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aim of this study was to evaluate the effect of cariporide, a selective Na(+)/H(+) exchange inhibitor, on isolated and cultured hepatic stellate cells (HSCs) and in 2 in vivo models of rat liver fibrosis. Platelet-derived growth factor (PDGF)-induced HSC proliferation, evaluated by measuring the percentage of bromodeoxyuridine-positive cells, was significantly inhibited by cariporide, with a maximal effect at 10 micromol/L. Incubation with cariporide did not inhibit PDGF-induced extracellular-regulated kinase 1/2 (ERK1/2), Akt (a downstream component of the phosphatidylinositol [PI]-3 kinase pathway), and protein kinase C (PKC) activation but reduced PDGF-induced activation of the Na(+)/H(+) exchanger, with a maximal effect at 10 micromol/L. Rats treated with dimethylnitrosamine (DMN; 10 mg/kg) for 1 and 5 weeks received a diet with or without 6 ppm cariporide. Treatment with cariporide reduced the degree of liver injury, as determined by alanine aminotransferase (ALT) values, also when administered after the induction of hepatic damage. This was associated with reduced HSC activation and proliferation and reduced collagen deposition, as determined by morphometric evaluation of alpha-smooth muscle actin (SMA)/proliferating cell nuclear antigen-positive cells and percentage of Sirius red-positive parenchyma, respectively. Moreover, cariporide was also able to reduce alpha(1)I procollagen messenger RNA (mRNA) expression. Similar effects were observed in bile duct-ligated (BDL) rats. In conclusion, selective inhibition of the Na(+)/H(+) exchanger by cariporide may represent an effective therapeutic strategy in the treatment of hepatic fibrosis.
Collapse
Affiliation(s)
- Antonio Di Sario
- Department of Gastroenterology, University of Ancona, Italy. a.disario@
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
68
|
Shi Y, Hsu JH, Hu L, Gera J, Lichtenstein A. Signal pathways involved in activation of p70S6K and phosphorylation of 4E-BP1 following exposure of multiple myeloma tumor cells to interleukin-6. J Biol Chem 2002; 277:15712-20. [PMID: 11872747 DOI: 10.1074/jbc.m200043200] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Interleukin-6 (IL-6) is a prominent tumor growth factor for malignant multiple myeloma cells. In addition to its known activation of the Janus tyrosine kinase-STAT and RAS-MEK-ERK pathways, recent work suggests that IL-6 can also activate the phosphatidylinositol 3-kinase (PI3-K)/AKT kinase pathway in myeloma cells. Because activation of the PI3-K/AKT as well as RAS-MEK-ERK pathways may result in downstream stimulation of the p70(S6K) (p70) and phosphorylation of the 4E-BP1 translational repressor, we assessed these potential molecular targets in IL-6-treated myeloma cells. IL-6 rapidly activated p70 kinase activity and p70 phosphorylation. Activation was inhibited by wortmannin, rapamycin, and the ERK inhibitors PD98059 and UO126, as well as by a dominant negative mutant of AKT. The concurrent requirements for both ERK and PI3-K/AKT appeared to be a result of their ability to phosphorylate p70 on different residues. In contrast, IL-6-induced phosphorylation of 4E-BP1 was inhibited by rapamycin, wortmannin, and dominant negative AKT but ERK inhibitors had no effect, indicating ERK function was dispensable. In keeping with these data, a dominant active AKT mutant was sufficient to induce 4E-BP1 phosphorylation but could not by itself activate p70 kinase activity. Prevention of IL-6-induced p70 activation and 4E-BP1 phosphorylation by the mammalian target of rapamycin inhibitors rapamycin and CCI-779 resulted in inhibition of IL-6-induced myeloma cell growth. These results indicate that both ERK and PI3-K/AKT pathways are required for optimal IL-6-induced p70 activity, but PI3-K/AKT is sufficient for 4E-BP1 phosphorylation. Both effects are mediated via mammalian target of rapamycin function, and, furthermore, these effects are critical for IL-6-induced tumor cell growth.
Collapse
Affiliation(s)
- Yijiang Shi
- Department of Medicine, West Los Angeles Veterans Affairs-UCLA Medical Center, Los Angeles, California 90073, USA
| | | | | | | | | |
Collapse
|
69
|
Vose JM, Chiu BCH, Cheson BD, Dancey J, Wright J. Update on epidemiology and therapeutics for non-Hodgkin's lymphoma. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2002; 2002:241-262. [PMID: 12446426 DOI: 10.1182/asheducation-2002.1.241] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This chapter presents updated information on the trends and patterns of non-Hodgkin's lymphoma (NHL) diagnoses as well as new information on chemotherapeutic and immunotherapeutic options for NHL treatment. In Section I, Dr. Brian Chiu summarizes the current knowledge regarding the etiologic factors and patterns of NHL as well as suggests future epidemiologic studies based on these preliminary results. In Section II, Dr. Bruce Cheson and colleagues outline new chemotherapeutic and small molecule antineoplastic agents with unique mechanisms of action such as protease inhibitors, farnesyl transferase or histone deacetylase inhibitors, and antisense oligonucleotides. In Section III, Dr. Julie Vose reviews the anti-lymphoma effects of monoclonal antibodies, radioimmunoconjugates, idiotype vaccines, and immunologic enhancing adjuvants with respect to mechanisms of action, clinical trials, and their potential for patient therapy.
Collapse
Affiliation(s)
- Julie M Vose
- University of Nebraska Medical Center, Nebraska Medical Center, Omaha 68198, USA
| | | | | | | | | |
Collapse
|