51
|
Romo de Vivar Chavez A, de Vera ME, Liang X, Lotze MT. The biology of interleukin-2 efficacy in the treatment of patients with renal cell carcinoma. Med Oncol 2009; 26 Suppl 1:3-12. [PMID: 19148593 DOI: 10.1007/s12032-008-9162-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Accepted: 12/18/2008] [Indexed: 01/22/2023]
Abstract
Renal cell carcinoma (RCC) is the eighth most common malignancy in adults in the United States. More than 50% of individuals present with metastatic disease and conventional chemotherapeutic strategies have been associated with poor response rates. Immunotherapy with Interleukin (IL)-2, however, induces durable remission, achieving >10 year recurrence free survival in 5-10% of patients with advanced RCC. First described as a T cell growth factor, IL-2 has a wide spectrum of effects in the immune system. Some of the possible mechanisms by which IL-2 carries out its anticancer effects include the augmentation of cytotoxic immune cell functions and reversal of T cell anergy, enabling delivery of immune cells and possibly serum components into tumor. IL-2 indirectly limits tumor escape mechanisms such as defective tumor cell expression of Class I or Class II molecules or expansion of regulatory T cells. Indirect effects on the tumor microenvironment are also likely and associated with rather dramatic T cell infiltration during the global delayed type hypersensitivity response that is associated with systemic IL-2 administration. The IL-2 signaling pathway, its effects on immune cells, and its role in various independent mechanisms of tumor surveillance likely play a role but little substantive data defining a clear phenotype or genotype of IL-2 responders distinguishing them from nonresponders has emerged in the last 25 years since IL-2 therapy was initiated. At best, we can only speculate that the disturbed homeostatic host/tumor interaction is reset in a small subset of patients allowing an antitumor response to recover or ensue.
Collapse
Affiliation(s)
- Antonio Romo de Vivar Chavez
- Department of Surgery, University of Pittsburgh, G.27A Hillman Cancer Center 5117 Centre Avenue, Pittsburgh, PA 15213, USA
| | | | | | | |
Collapse
|
52
|
Affiliation(s)
- Jan D Bos
- Department of Dermatology, Academic Medical Center, University of Amsterdam, 1100 DE, Amsterdam, The Netherlands
| | | |
Collapse
|
53
|
de Bruin EC, Medema JP. Apoptosis and non-apoptotic deaths in cancer development and treatment response. Cancer Treat Rev 2008; 34:737-49. [PMID: 18722718 DOI: 10.1016/j.ctrv.2008.07.001] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Revised: 07/08/2008] [Accepted: 07/11/2008] [Indexed: 01/01/2023]
|
54
|
Chouaib S, Meslin F, Thiery J, Mami-Chouaib F. Tumor resistance to specific lysis: a major hurdle for successful immunotherapy of cancer. Clin Immunol 2008; 130:34-40. [PMID: 19013109 DOI: 10.1016/j.clim.2008.08.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 08/10/2008] [Indexed: 01/22/2023]
Abstract
Research over the past decade in tumor immunology has shown that immune reactivity to tumor antigens can decrease tumor growth in experimental models. These observations have been translated into clinical studies involving both passive and active forms of immunotherapy. Immunotherapy, an alternative treatment for cancer, is confronted to a major hurdle: tumor escape of specific lysis. Cancer antigen-specific cytotoxic T lymphocytes (CTL) are the major effectors used in immunotherapy against cancer cells. However, large established tumors are usually not fully controlled by CTL. These effector cells could indeed have a dual activity, which allow cancer cells to escape destruction. In this review, we will focus on the essential role of the p53 tumor suppressor gene in the dynamic regulation of tumor cell death induced by cytotoxic T lymphocytes and the involving of structural changes of cytoskeleton in the acquisition of tumor resistance.
Collapse
Affiliation(s)
- Salem Chouaib
- INSERM U753 - Immunologie des tumeurs Humaines, Institut Gustave Roussy, 94805 Villejuif, France.
| | | | | | | |
Collapse
|
55
|
Leverkus M, Diessenbacher P, Geserick P. FLIP ing the coin? Death receptor-mediated signals during skin tumorigenesis. Exp Dermatol 2008; 17:614-22. [PMID: 18558995 DOI: 10.1111/j.1600-0625.2008.00728.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Keratinocyte skin cancer is a multi-step process, during which a number of obstacles have to be overcome by the tumor cell to allow the development of a manifest tumor. Beside proliferation and immortality, apoptosis resistance is one additional and critical step during skin carcinogenesis. Over the past two decades, much has been learned about the prototypical membrane-bound inducers of apoptosis, namely the death receptors and their ligands, and the apoptosis signalling pathways activated by death receptors have been elucidated in great detail. In contrast, much less is known about the tissue-specific role of the death receptor/ligands systems during the development of skin cancer. Here, we summarize and discuss the role of this intriguing receptor family and the potential mechanistical impact of the intracellular caspase-8 inhibitor cFLIP for keratinocyte skin cancer. Given more recent data about cFLIP and its isoforms, a more complex regulatory role of cFLIP can be suspected. Indeed, cFLIP may not solely interfere with death receptor-mediated apoptosis signalling pathways, but may positively or negatively influence other, potential harmful signalling pathways such as the production of inflammatory cytokines, tumor cell migration or the activation of transcription factors such as NF-kappaB, considered crucial during skin tumorigenesis. In this respect, cFLIP may act to 'FLIP the coin' during the development of keratinocyte skin cancer.
Collapse
Affiliation(s)
- Martin Leverkus
- Department of Dermatology and Venerology, Laboratory for Experimental Dermatology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
| | | | | |
Collapse
|
56
|
Wang L, Azad N, Kongkaneramit L, Chen F, Lu Y, Jiang BH, Rojanasakul Y. The Fas death signaling pathway connecting reactive oxygen species generation and FLICE inhibitory protein down-regulation. THE JOURNAL OF IMMUNOLOGY 2008; 180:3072-80. [PMID: 18292530 DOI: 10.4049/jimmunol.180.5.3072] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Fas-mediated apoptosis plays an important role in normal tissue homeostasis, and disruption of this death pathway contributes to many human diseases. Induction of apoptosis via Fas activation has been associated with reactive oxygen species (ROS) generation and down-regulation of FLICE inhibitory protein (FLIP); however, the relationship between these two events and their role in Fas-mediated apoptosis are unclear. We show herein that ROS are required for FLIP down-regulation and apoptosis induction by Fas ligand (FasL) in primary lung epithelial cells. ROS mediate the down-regulation of FLIP by ubiquitination and subsequent degradation by proteasome. Inhibition of ROS by antioxidants or by ectopic expression of ROS-scavenging enzymes glutathione peroxidase and superoxide dismutase effectively inhibited FLIP down-regulation and apoptosis induction by FasL. Hydrogen peroxide is a primary oxidative species responsible for FLIP down-regulation, whereas superoxide serves as a source of peroxide and a scavenger of NO, which positively regulates FLIP via S-nitrosylation. NADPH oxidase is a key source of ROS generation induced by FasL, and its inhibition by dominant-negative Rac1 expression or by chemical inhibitor decreased the cell death response to FasL. Taken together, our results indicate a novel pathway of FLIP regulation by an interactive network of reactive oxygen and nitrogen species that provides a key mechanism of apoptosis regulation in Fas-induced cell death and related apoptosis disorders.
Collapse
Affiliation(s)
- Liying Wang
- Pathology and Physiology Research Branch, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | | | | | | | | | | | | |
Collapse
|
57
|
Targeting Bcl-2 family proteins modulates the sensitivity of B-cell lymphoma to rituximab-induced apoptosis. Blood 2008; 112:3312-21. [PMID: 18689543 DOI: 10.1182/blood-2007-11-124487] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The chimeric monoclonal antibody rituximab is the standard of care for patients with B-cell non-Hodgkin lymphoma (B-NHL). Rituximab mediates complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity of CD20-positive human B cells. In addition, rituximab sensitizes B-NHL cells to cytotoxic chemotherapy and has direct apoptotic and antiproliferative effects. Whereas expression of the CD20 antigen is a natural prerequisite for rituximab sensitivity, cell-autonomous factors determining the response of B-NHL to rituximab are less defined. To this end, we have studied rituximab-induced apoptosis in human B-NHL models. We find that rituximab directly triggers apoptosis via the mitochondrial pathway of caspase activation. Expression of antiapoptotic Bcl-xL confers resistance against rituximab-induced apoptosis in vitro and rituximab treatment of xenografted B-NHL in vivo. B-NHL cells insensitive to rituximab-induced apoptosis exhibit increased endogenous expression of multiple antiapoptotic Bcl-2 family proteins, or activation of phosphatidylinositol-3-kinase signaling resulting in up-regulation of Mcl-1. The former resistance pattern is overcome by treatment with the BH3-mimetic ABT-737, the latter by combining rituximab with pharmacologic phosphatidylinositol-3-kinase inhibitors. In conclusion, sensitivity of B-NHL cells to rituximab-induced apoptosis is determined at the level of mitochondria. Pharmacologic modulation of Bcl-2 family proteins or their upstream regulators is a promising strategy to overcome rituximab resistance.
Collapse
|
58
|
Aberrant expression of the Th2 cytokine IL-21 in Hodgkin lymphoma cells regulates STAT3 signaling and attracts Treg cells via regulation of MIP-3alpha. Blood 2008; 112:3339-47. [PMID: 18684866 DOI: 10.1182/blood-2008-01-134783] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The malignant Hodgkin/Reed-Sternberg (HRS) cells of classical Hodgkin lymphoma (HL) are derived from mature B cells, but have lost a considerable part of the B cell-specific gene expression pattern. Consequences of such a lineage infidelity for lymphoma pathogenesis are currently not defined. Here, we report that HRS cells aberrantly express the common cytokine-receptor gamma-chain (gamma(c)) cytokine IL-21, which is usually restricted to a subset of CD4(+) T cells, and the corresponding IL-21 receptor. We demonstrate that IL-21 activates STAT3 in HRS cells, up-regulates STAT3 target genes, and protects HRS cells from CD95 death receptor-induced apoptosis. Furthermore, IL-21 is involved in up-regulation of the CC chemokine macrophage-inflammatory protein-3alpha (MIP-3alpha) in HRS cells. MIP-3alpha in turn attracts CCR6(+)CD4(+)CD25(+)FoxP3(+)CD127(lo) regulatory T cells toward HRS cells, which might favor their immune escape. Together, these data support the concept that aberrant expression of B lineage-inappropriate genes plays an important role for the biology of HL tumor cells.
Collapse
|
59
|
Molecular basis of parthenolide-dependent proapoptotic activity in cancer cells. Folia Histochem Cytobiol 2008; 46:129-35. [PMID: 18519227 DOI: 10.2478/v10042-008-0019-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This review outlines the molecular events that accompany the anti-tumor action of parthenolide (PN). Parthenolide (PN) is naturally derived compound, isolated from plant Tanacetum parthenium. PN has been previously shown to withdraw cells from cell cycle or to promote cell differentiation, and finally to induce programmed cell death. Recent advances in molecular biology indicate that this sesquiterpene lactone might evoke the above-mentioned effects by indirect action on genes. PN was shown to inhibit NF-kappaB- and STATs-mediated antiapoptotic gene transcription. On one hand, the proapoptotic activity of PN includes stimulation of intrinsic apoptotic pathway with the higher level of intracellular ROS and modifications of Bcl-2 family proteins (conformational changes of Bak and Bax, Bid cleavage). On the other hand, PN amplifies the apoptotic signal through the sensitization of cancer cells to extrinsic apoptosis, induced by TNF-alpha. These effects are specific to tumor cells. Unique properties of PN make this agent a promising metabolic inhibitor to retard tumorigenesis and to suppress tumor growth.
Collapse
|
60
|
|
61
|
Mao C, Patterson NM, Cherian MT, Aninye IO, Zhang C, Montoya JB, Cheng J, Putt KS, Hergenrother PJ, Wilson EM, Nardulli AM, Nordeen SK, Shapiro DJ. A new small molecule inhibitor of estrogen receptor alpha binding to estrogen response elements blocks estrogen-dependent growth of cancer cells. J Biol Chem 2008; 283:12819-30. [PMID: 18337247 PMCID: PMC2442351 DOI: 10.1074/jbc.m709936200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 03/12/2008] [Indexed: 12/21/2022] Open
Abstract
Estrogen receptor alpha (ERalpha) plays an important role in several human cancers. Most current ERalpha antagonists bind in the receptor ligand binding pocket and compete for binding with estrogenic ligands. Instead of the traditional approach of targeting estrogen binding to ER, we describe a strategy using a high throughput fluorescence anisotropy microplate assay to identify small molecule inhibitors of ERalpha binding to consensus estrogen response element (cERE) DNA. We identified small molecule inhibitors of ERalpha binding to the fluorescein-labeled (fl)cERE and evaluated their specificity, potency, and efficacy. One small molecule, theophylline, 8-[(benzylthio)methyl]-(7CI,8CI) (TPBM), inhibited ERalpha binding to the flcERE (IC(50) approximately 3 microm) and inhibited ERalpha-mediated transcription of a stably transfected ERE-containing reporter gene. Inhibition by TPBM was ER-specific, because progesterone and glucocorticoid receptor transcriptional activity were not significantly inhibited. In tamoxifen-resistant breast cancer cells that overexpress ERalpha, TPBM inhibited 17beta-estradiol (E(2))-ERalpha (IC(50) 9 microm) and 4-hydroxytamoxifen-ERalpha-mediated gene expression. Chromatin immunoprecipitation showed TPBM reduced E(2).ERalpha recruitment to an endogenous estrogen-responsive gene. TPBM inhibited E(2)-dependent growth of ERalpha-positive cancer cells (IC(50) of 5 microm). TPBM is not toxic to cells and does not affect estrogen-independent cell growth. TPBM acts outside of the ER ligand binding pocket, does not act by chelating the zinc in ER zinc fingers, and differs from known ERalpha inhibitors. Using a simple high throughput screen for inhibitors of ERalpha binding to the cERE, a small molecule inhibitor has been identified that selectively inhibits ERalpha-mediated gene expression and estrogen-dependent growth of cancer cells.
Collapse
Affiliation(s)
- Chengjian Mao
- Department of Biochemistry, and Chemistry, University of Illinois, Urbana, Illinois 61810-3602, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
62
|
Iyer AKV, Azad N, Wang L, Rojanasakul Y. Role of S-nitrosylation in apoptosis resistance and carcinogenesis. Nitric Oxide 2008; 19:146-51. [PMID: 18474261 DOI: 10.1016/j.niox.2008.04.019] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 04/15/2008] [Accepted: 04/16/2008] [Indexed: 12/14/2022]
Abstract
Nitric oxide (NO) has been widely recognized as a positive regulator of tumorigenesis and cancer progression through its ability to regulate important proteins in various signal transduction pathways. S-Nitrosylation, or covalent attachment of NO to protein sulphydryl groups, has gained prominence as an important mechanism by which NO modulates physiologic and pathologic cellular responses. In this article, we discuss S-nitrosylation of two key apoptosis-regulatory proteins of the intrinsic and extrinsic death pathways, namely B-cell lymphoma-2 (Bcl-2) and FLICE-inhibitory protein (FLIP). These proteins have been shown to be upregulated in a variety of tumors and have been implicated with cancer chemoresistance through dysregulation of apoptosis. S-Nitrosylation of these proteins precludes their ubiquitination and subsequent degradation by the proteasome, thus accentuating their anti-apoptotic effect which is critical in the context of tumorigenic potential and cancer progression. We propose that such post-translational modifications of proteins by NO may be a general mechanism that tumor cells exploit to tilt the scales towards survival and proliferation by evading cell death.
Collapse
Affiliation(s)
- Anand Krishnan V Iyer
- Department of Pharmaceutical Sciences, West Virginia University, P.O. Box 9530, Morgantown, WV 26506, USA
| | | | | | | |
Collapse
|
63
|
Iwase M, Takaoka S, Uchida M, Yoshiba S, Kondo G, Watanabe H, Ohashi M, Nagumo M. Epidermal growth factor receptor inhibitors enhance susceptibility to Fas-mediated apoptosis in oral squamous cell carcinoma cells. Oral Oncol 2008; 44:361-8. [PMID: 17689285 DOI: 10.1016/j.oraloncology.2007.04.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 04/25/2007] [Accepted: 04/26/2007] [Indexed: 01/08/2023]
Abstract
Molecular inhibition of epidermal growth factor receptor (EGFR) signaling is a promising cancer treatment strategy. We examined whether inhibition of EGFR signaling would affect the susceptibility of oral squamous cell carcinoma (OSCC) cells to Fas-mediated apoptosis. Treatment of OSCC cells with an anti-EGFR monoclonal antibody, C225, and an EGFR tyrosine kinase inhibitor, AG1478, which target the extracellular and intracellular domains of the receptor, respectively, inhibited phosphorylation of EGFR and its downstream effector molecule Akt and amplified the induction of Fas-mediated apoptosis. In OSCC cells treated with EGFR inhibitors, Fas-mediated apoptosis was accompanied by caspase-8 activation but not Bid cleavage. Caspase-3 and -8 inhibitors reduced the effect of EGFR inhibitors on Fas-mediated apoptosis in OSCC cells, but a caspase-9 inhibitor did not. These results indicate that the pro-apoptotic activity of EGFR inhibitors in OSCC cells depends on the extrinsic pathway of the caspase cascade. Although EGFR inhibitors did not affect the expression of Fas, the Fas-associated death domain protein, or procaspase-8 in OSCC cells, the inhibition downregulated cellular FLICE-inhibitory protein (c-FLIP). Moreover, knockdown of c-FLIP in HSC-2 cells with a small interfering RNA strongly enhanced Fas-mediated apoptosis. These results suggest that the EGFR signaling pathway may, in part, regulate Fas-mediated apoptosis in OSCC cells through c-FLIP expression.
Collapse
Affiliation(s)
- Masayasu Iwase
- Department of Oral and Maxillofacial Surgery, Showa University School of Dentistry, 2-1-1, Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
64
|
Perez LE, Parquet N, Shain K, Nimmanapalli R, Alsina M, Anasetti C, Dalton W. Bone marrow stroma confers resistance to Apo2 ligand/TRAIL in multiple myeloma in part by regulating c-FLIP. THE JOURNAL OF IMMUNOLOGY 2008; 180:1545-55. [PMID: 18209050 DOI: 10.4049/jimmunol.180.3.1545] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Apo2 ligand (Apo2L)/TRAIL induces apoptosis of cancer cells that express the specific receptors while sparing normal cells. Because the tumor microenvironment protects myeloma from chemotherapy, we investigated whether hemopoietic stroma induces resistance to Apo2L/TRAIL apoptosis in this disease. Apo2L/TRAIL-induced death was diminished in myeloma cell lines (RPMI 8226, U266, and MM1s) directly adhered to a human immortalized HS5 stroma cell line but not adhered to fibronectin. In a Transwell assay, with myeloma in the upper well and HS5 cells in the lower well, Apo2L/TRAIL apoptosis was reduced when compared with cells exposed to medium in the lower well. Using HS5 and myeloma patients' stroma-conditioned medium, we determined that soluble factor(s) produced by stroma-myeloma interactions are responsible for a reversible Apo2/TRAIL apoptosis resistance. Soluble factor(s) attenuated procaspase-8, procaspase-3, and poly(ADP-ribose) polymerase cleavage and diminished mitochondrial membrane potential changes without affecting Bcl-2 family proteins and/or Apo2L/TRAIL receptors. Soluble factor(s) increased the baseline levels of the anti-apoptotic protein c-FLIP in all cell lines tested. Inhibition of c-FLIP by means of RNA interference increased Apo2/TRAIL sensitivity in RPMI 8226 cells. Unlike direct adhesion to fibronectin, soluble factor(s) have no impact on c-FLIP redistribution within cellular compartments. Cyclohexamide restored Apo2L/TRAIL sensitivity in association with down-regulation of c-FLIP, suggesting that c-FLIP synthesis, not intracellular traffic, is essential for soluble factor(s) to regulate c-FLIP. Additionally, IL-6 conferred resistance to Apo2L/TRAIL-mediated apoptosis in association with increased c-FLIP levels. In conclusion, the immune cytotoxic effect of Apo2L/TRAIL can be restored at least in part by c-FLIP pathway inhibitors.
Collapse
Affiliation(s)
- Lia Elena Perez
- Blood and Marrow Transplantation Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA.
| | | | | | | | | | | | | |
Collapse
|
65
|
Resistance to FasL and tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis in Sezary syndrome T-cells associated with impaired death receptor and FLICE-inhibitory protein expression. Blood 2008; 111:4780-7. [PMID: 18314443 DOI: 10.1182/blood-2007-08-109074] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Because of the low proliferative potential of tumor cells in patients with Sézary syndrome (SzS), their accumulation has been suggested to be due to defective regulation of apoptosis. We analyzed the sensitivity to soluble Fas-ligand (FasL) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), 2 members of the TNF superfamily in peripheral blood leukocytes (PBL) from patients with SzS. Compared with healthy donors, CD4(+) cells from patients with SzS were completely resistant to FasL in 9 of 16 cases. Of these 9 FasL-resistant cases, 4 revealed a loss in Fas (CD95) expression, whereas the remaining 5 exhibited normal or enhanced Fas expression. In the latter 5 cases, the apoptosis inhibitor cFLIP was overexpressed in CD4(+)/CD26(-) tumor cells compared with CD4(+)/CD26(-) cells from Fas-expressing FasL-sensitive patients and healthy donors. Furthermore, resistance to TRAIL and tumor cell-restricted loss of TRAIL-receptor 2 were observed in 16 of 16 SzS PBLs. It is noteworthy that resistance to FasL could be overcome by the use of a hexameric FasL or upon exposure of SzS cells to interferon-alpha (IFN-alpha) or IFN-gamma, the latter by an increase of Fas expression. Our data on primary SzS lymphocytes reveal frequent resistance to apoptosis induced by FasL and TRAIL, which may contribute to their accumulation in patients with SzS and be relevant at a therapeutic level.
Collapse
|
66
|
Overexpression of cFLIP in head and neck squamous cell carcinoma and its clinicopathologic correlations. J Cancer Res Clin Oncol 2007; 134:609-15. [DOI: 10.1007/s00432-007-0325-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Accepted: 09/27/2007] [Indexed: 10/22/2022]
|
67
|
Yang D, Ud Din N, Browning DD, Abrams SI, Liu K. Targeting lymphotoxin beta receptor with tumor-specific T lymphocytes for tumor regression. Clin Cancer Res 2007; 13:5202-10. [PMID: 17785576 DOI: 10.1158/1078-0432.ccr-07-1161] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE One of the impediments of immunotherapy against cancer is the suppression of tumor-specific CTLs in the tumor microenvironment, partly due to the selective inhibition of the perforin pathway and the emergence of Fas-resistant tumors. Therefore, we sought to identify perforin- and Fas-independent cytotoxic pathways and explored the potential of targeting LTbetaR with tumor-specific CTLs to induce tumor rejection in vivo. EXPERIMENTAL DESIGN Fas-resistant tumors were examined for their susceptibility to perforin-deficient (pfp) CTLs via CTL adoptive transfer in mouse models of experimental lung metastasis. The specificity of LTbetaR, a cell surface death receptor, in causing tumor rejection by CTLs was analyzed by LTbetaR-specific neutralizing monoclonal antibody in vitro. The specificity and efficacy of LTbetaR in the suppression of established tumors was further investigated by silencing LTbetaR in tumor cells in vivo. RESULTS pfp CTLs exhibited significant cytotoxicity against Fas-resistant tumors in vivo. The perforin- and Fas-independent cytotoxicity was directly mediated, at least in part, by the adoptively transferred CTLs. It was observed that LTbetaR was expressed on the tumor cell surface, and LTalpha, LTbeta, and LIGHT, all of which are ligands for LTbetaR, were either constitutively expressed or activated in the tumor-specific CTLs and primary CD8(+) T cells. Blocking LTbetaR with LTbetaR-specific neutralizing monoclonal antibody decreased CTL cytotoxicity in vitro. Silencing LTbetaR using LTbetaR-specific short hairpin RNA reduced the ability of pfp CTLs to induce tumor rejection in vivo. CONCLUSION LTbetaR directly mediates CTL-directed tumor rejection in vivo. Targeting LTbetaR with tumor-specific CTLs is a potential therapeutic approach.
Collapse
Affiliation(s)
- Dafeng Yang
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | |
Collapse
|
68
|
Meslin F, Thiery J, Richon C, Jalil A, Chouaib S. Granzyme B-induced cell death involves induction of p53 tumor suppressor gene and its activation in tumor target cells. J Biol Chem 2007; 282:32991-9. [PMID: 17855337 DOI: 10.1074/jbc.m705290200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this study we investigated the involvement of p53 in cytotoxic T-lymphocyte (CTL)-induced tumor target cell killing mediated by the perforin/granzymes pathway. For this purpose we used a human CTL clone (LT12) that kills its autologous melanoma target cells (T1), harboring a wild type p53. We demonstrated initially that LT12 kills its T1 target in a perforin/granzymes-dependent manner. Confocal microscopy and Western blot analysis indicated that conjugate formed between LT12 and T1 resulted in rapid cytoplasmic accumulation of p53 and its activation in T1 target cells. Cytotoxic assay using recombinant granzyme B (GrB) showed that this serine protease is the predominant factor inducing such accumulation. Furthermore, RNA interference-mediated lowering of the p53 protein in T1 cells or pifithrin-alpha-induced p53-specific inhibition activity significantly decreased CTL-induced target killing mediated by CTL or recombinant GrB. This emphasizes that p53 is an important determinant in granzyme B-induced apoptosis. Our data show furthermore that when T1 cells were treated with streptolysin-O/granzyme B, specific phosphorylation of p53 at Ser-15 and Ser-37 residues was observed subsequent to the activation of the stress kinases ataxia telangiectasia mutated (ATM) and p38K. Treatment of T1 cells with pifithrin-alpha resulted in inhibition of p53 phosphorylation at these residues and in a significant decrease in GrB-induced apoptotic T1 cell death. Furthermore, small interference RNAs targeting p53 was also accompanied by an inhibition of streptolysin-O/granzyme B-induced apoptotic T1 cell death. The present study supports p53 induction after CTL-induced stress in target cells. These findings provide new insight into a potential role of p53 as a component involved in the dynamic regulation of the major pathway of CTL-mediated cell death and may have therapeutic implications.
Collapse
Affiliation(s)
- Franck Meslin
- INSERM U753, Laboratoire d'Immunologie des Tumeurs Humaines, Interaction Effecteurs Cytotoxiques-Système Tumoral, Institut Gustave Roussy PR1, IFR 54,Villejuif Cedex, France
| | | | | | | | | |
Collapse
|
69
|
Berg D, Lehne M, Müller N, Siegmund D, Münkel S, Sebald W, Pfizenmaier K, Wajant H. Enforced covalent trimerization increases the activity of the TNF ligand family members TRAIL and CD95L. Cell Death Differ 2007; 14:2021-34. [PMID: 17703232 DOI: 10.1038/sj.cdd.4402213] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Variants of human TRAIL (hTRAIL) and human CD95L (hCD95L), encompassing the TNF homology domain (THD), interact with the corresponding receptors and stimulate CD95 and TRAILR2 signaling after cross-linking. The murine counterparts (mTRAIL, mCD95L) showed no or only low receptor binding and were inactive/poorly active after cross-linking. The stalk region preceding the THD of mCD95L conferred secondary aggregation and restored CD95 activation in the absence of cross-linking. A corresponding variant of mTRAIL, however, was still not able to activate TRAIL death receptors, but gained good activity after cross-linking. Notably, disulfide-bonded fusion proteins of the THD of mTRAIL and mCD95L with a subdomain of the tenascin-C (TNC) oligomerization domain, which still assembled into trimers, efficiently interacted with their cognate cellular receptors and robustly stimulated CD95 and TRAILR2 signaling after secondary cross-linking. Introduction of the TNC domain also further enhanced the activity of THD encompassing variants of hTRAIL and hCD95L. Thus, spatial fixation of the N-terminus of the THD appears necessary in some TNF ligands to ensure proper receptor binding. This points to yet unanticipated functions of the stalk and/or transmembrane region of TNF ligands for the functionality of these molecules and offers a broadly applicable option to generate recombinant soluble ligands of the TNF family with superior activity.
Collapse
Affiliation(s)
- D Berg
- Department of Molecular Internal Medicine, Medical Clinic and Polyclinic II, University of Wuerzburg, Wuerzburg 97070, Germany
| | | | | | | | | | | | | | | |
Collapse
|
70
|
Nakajima A, Kojima Y, Nakayama M, Yagita H, Okumura K, Nakano H. Downregulation of c-FLIP promotes caspase-dependent JNK activation and reactive oxygen species accumulation in tumor cells. Oncogene 2007; 27:76-84. [PMID: 17599041 DOI: 10.1038/sj.onc.1210624] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Nuclear factor-kappa B (NF-kappaB) inhibits cell death through suppression of the caspase cascade, the c-Jun N-terminal kinase (JNK) pathway, and reactive oxygen species (ROS) accumulation. To suppress this antiapoptotic function of NF-kappaB might be a promising strategy to increase susceptibility of tumor cells to stress-induced cell death. We have recently shown that tumor necrosis factor (TNF)alpha induces caspase-dependent and -independent JNK activation and ROS accumulation in cellular FLICE-inhibitory protein (c-Flip)(-/-) murine embryonic fibroblasts (MEFs). To apply this observation to tumor therapy, we knocked down c-FLIP by RNA interference in various tumor cells. Consistent with the results using c-Flip(-/-) MEFs, we found that TNFalpha stimulation induced caspase-dependent prolonged JNK activation and ROS accumulation, followed by apoptotic and necrotic cell death in various tumor cells. Furthermore, TNFalpha and Fas induced the cleavage of mitogen-activated protein kinase/ERK kinase kinase (MEKK)1, resulting in generation of a constitutive active form of MEKK1 leading to JNK activation in c-FLIP knockdown cells. Given that ROS accumulation and necrotic cell death enhance inflammation followed by compensatory proliferation of tumor cells, selective suppression of caspase-dependent ROS accumulation will be an alternative strategy to protect cells from ROS-dependent DNA damage and compensatory tumor progression.
Collapse
Affiliation(s)
- A Nakajima
- Department of Immunology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo, Japan
| | | | | | | | | | | |
Collapse
|
71
|
Gomez GG, Kruse CA. Cellular and functional characterization of immunoresistant human glioma cell clones selected with alloreactive cytotoxic T lymphocytes reveals their up-regulated synthesis of biologically active TGF-beta. J Immunother 2007; 30:261-73. [PMID: 17414317 PMCID: PMC1894900 DOI: 10.1097/01.cji.0000211339.81211.25] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Two immunoresistant (IR) glioma cell variants, 13-06-IR29 and 13-06-IR30, were cloned from 13-06-MG glioma cell populations after receiving continuous immunoselective pressure from multiple alloreactive cytotoxic T lymphocyte (aCTL) preparations. Reapplication of aCTL immunoselective pressure to the IR clones, displaying a partial regain in sensitivity to aCTL after removal of the selective pressure, restored the resistance. The IR variants exhibited cross-resistance to non-human leukocyte antigen (HLA)-restricted effector cells and gamma-irradiation, but not to carmustine. The IR clones were characterized for factors that might contribute to the immunoresistance. The aCTL adhesion to extracellular matrix extracts derived from either the IR clones or the parental cells was similar and not impaired. Furthermore, aCTL binding to parental cells and IR clones was equal. Down-regulation of the cell recognition molecules, class I HLA or intercellular adhesion molecule-1 (ICAM-1), that would inhibit their recognition by aCTL was not observed on the IR clones. The down-regulation of Fas by the IR clones correlated with their resistance to FasL-induced apoptosis. HLA-G or FasL that might provide an immunotolerant environment or provide a means of counterattack to aCTL, respectively, were not associated with the IR phenotype. The aCTL, coincubated with the IR clones and parental cells, displayed up-regulation of multiple secreted cytokines. A significant up-regulation of bioactive transforming growth factor (TGF)-beta was observed in the IR clones compared with the parental cells. These data suggest that increased secretion of bioactive TGF-beta may inhibit aCTL lysis of the IR clones. Disruption of the TGF-beta signaling pathway may circumvent the resistance.
Collapse
Affiliation(s)
- German G. Gomez
- Department of Pathology, University of Colorado Health Sciences Center, Denver, CO
| | - Carol A. Kruse
- Division of Cancer Biology and Brain Tumor Research Program, The La Jolla Institute for Molecular Medicine, San Diego, CA
| |
Collapse
|
72
|
Wang W, Wang S, Song X, Sima N, Xu X, Luo A, Chen G, Deng D, Xu Q, Meng L, Lu Y, Ma D. The relationship between c-FLIP expression and human papillomavirus E2 gene disruption in cervical carcinogenesis. Gynecol Oncol 2007; 105:571-7. [PMID: 17433827 DOI: 10.1016/j.ygyno.2007.01.051] [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: 11/28/2006] [Revised: 01/09/2007] [Accepted: 01/17/2007] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Human papillomavirus (HPV) is the essential causative factor in cervical carcinogenesis, and apoptosis inhibition is one of the key features of HPV-induced malignant transformation. This study is to investigate the possible cause-effect association between high-risk HPV and cellular FLICE-like inhibitory protein (c-FLIP), an important apoptosis regulator, during cervical carcinogenesis. METHODS A series of 80 archival samples, including 20 squamous cervical carcinomas (SCC) 54 cervical intraepithelial neoplasia (CIN) lesions and 6 normal cervical tissues, were subjected for c-FLIP immunohistochemical staining and HPV HC-II analysis. Typing HPV-16 infection was analyzed by the polymerase chain reaction (PCR), and its status was assessed with the integrity and disruption of the HPV-16 E2 gene, which was amplified in three overlapping fragments. RESULTS The types of HR-HPV infection and E2 disruption were associated closely with cervical lesion severity. There was a significant relationship between lesion grade and c-FLIP expression level. c-FLIP overexpression was also closely associated with HR-HPV infection and its integration status. Multivariate regression analysis revealed c-FLIP as a strong independent predictor for CIN, with 100% PPV, and showed 90.9% PPV in detecting HR-HPV, and remained a significance factor to rule out which case has no HR-HPV integration, with a 94.7% sensitivity and a 90.0% NPV. CONCLUSIONS The present data approved that c-FLIP overexpression is related significantly to the presence of HR-HPV infection and its integration status during progression of cervical squamous cell cancer and confirmed the role of c-FLIP as an early marker of cervical carcinogenesis.
Collapse
Affiliation(s)
- Wei Wang
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
73
|
Abstract
Death receptor ligands (FasL, TRAIL) activate apoptosis in cells expressing the cognate receptors. Evidence suggests that these ligands also deliver pro-inflammatory signals. In the tumor microenvironment, "Fas counterattack" mounted by tumors against immune cells is mediated by tumor-associated FasL. But death ligands crosslinking their receptors also induce inhibition of apoptosis and activation of the transcription factor, NFkappaB, with a subsequent burst of pro-inflammatory cytokine production and tumor growth promotion. NFkappaB, a key link between inflammation and cancer, regulates dual activities of death ligands, depending on molecular signals in the tumor microenvironment. This paper focuses on death ligands as an example of the extensive repertoire of strategies devised by tumors for escape from immune control.
Collapse
Affiliation(s)
- Theresa L Whiteside
- Department of Pathology, Immunology and Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
| |
Collapse
|
74
|
Wieckowski E, Atarashi Y, Stanson J, Sato TA, Whiteside TL. FAP-1-mediated activation of NF-kappaB induces resistance of head and neck cancer to Fas-induced apoptosis. J Cell Biochem 2007; 100:16-28. [PMID: 16888780 DOI: 10.1002/jcb.20922] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Molecular mechanisms responsible for tumor resistance to apoptosis often involve the Fas/FasL pathway. While squamous cell carcinomas of the head and neck (SCCHN) express both Fas and FasL, their resistance to self-induced apoptosis or apoptosis mediated by Fas agonistic antibody (CH-11Ab) was independent of the level of Fas surface expression or the presence of soluble Fas in supernatants of primary or metastatic SCCHN cell lines. By in vitro immunoselection, using PCI-15A cell line treated with successive cycles of CH-11 Ab, Fas-resistant sublines with the parental genotype were selected. Such sublines failed to cleave caspase-8 upon Fas engagement and were resistant to CH-11 Ab, although they remained sensitive to VP-16 or staurosporin. In the presence of cycloheximide, the selected SCCHN sublines become susceptible to CH-11 Ab, and showed cleavage of caspase-8, suggesting that apoptosis resistance was mediated by an inhibitory protein(s) acting upstream of caspase-8. Overexpression of Fas-associated phosphatase 1 (FAP-1), but not cellular FLICE-inhibitory protein (cFLIP) in SCCHN sublines was documented by Western blots and RT-PCR analyses. The FAP-1+ selected sublines also downregulated cell surface Fas. A high phosphorylation level of IkappaB kappa, NFkappaB activation and upregulation of Bcl-2 expression were observed in the FAP-1+ sublines. Treatment with the phosphatase inhibitor, orthovanadate, or silencing of FAP-1 with siRNA abolished their resistance to apoptosis, suggesting that FAP-1 phosphatase activity could be responsible for NF-kappaB activation and resistance of SCCHN cells to Fas-mediated apoptosis.
Collapse
Affiliation(s)
- Eva Wieckowski
- University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15213, USA
| | | | | | | | | |
Collapse
|
75
|
Silbermann K, Grassmann R. Human T cell leukemia virus type 1 Tax-induced signals in cell survival, proliferation, and transformation. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/sita.200600119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
76
|
de Hooge ASK, Berghuis D, Santos SJ, Mooiman E, Romeo S, Kummer JA, Egeler RM, van Tol MJD, Melief CJM, Hogendoorn PCW, Lankester AC. Expression of Cellular FLICE Inhibitory Protein, Caspase-8, and Protease Inhibitor-9 in Ewing Sarcoma and Implications for Susceptibility to Cytotoxic Pathways. Clin Cancer Res 2007; 13:206-14. [PMID: 17200356 DOI: 10.1158/1078-0432.ccr-06-1457] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Ewing sarcoma is a common pediatric bone tumor with an unfavorable prognosis for metastatic or recurrent disease. Cellular immunotherapy may provide new treatment options and depends on the cytolytic death receptor and perforin/granzyme pathways. Expression of death receptor pathway inhibitor cellular FLICE inhibitory protein (cFLIP), initiator caspase-8, and granzyme B inhibitor protease inhibitor-9 (PI-9) have been reported to determine susceptibility to cell- and chemotherapy-mediated killing in several tumor types. Here, we have studied their in vitro and in vivo expression in Ewing sarcoma and the implications for susceptibility to cytotoxicity. EXPERIMENTAL DESIGN Ewing sarcoma cell lines (n = 8) were tested for cFLIP, PI-9, and caspase-8 expression. Functional significance was tested by anti-Fas antibody (death receptor pathway) or natural killer cell (perforin/granzyme pathway) treatment. Immunohistochemistry was done on 28 sections from 18 patients. In half of the cases, sequential material, including metastases, was available. RESULTS Although all tested Ewing sarcoma cell lines expressed cFLIP, resistance to CD95/Fas-mediated apoptosis was only observed in two cell lines lacking caspase-8 expression. PI-9 was expressed at low levels in four of eight Ewing sarcoma cell lines, but positive cell lines remained susceptible to perforin/granzyme-mediated killing. In primary Ewing sarcoma, including metastases, cFLIP was abundantly expressed in 18 of 18 patients. Caspase-8 was expressed in all patients but showed more intertumoral and intratumoral variation in both intensity and heterogeneity of staining. PI-9, in contrast, was undetectable. CONCLUSIONS The expression patterns of cFLIP, caspase-8, and the absence of PI-9 provide a rationale to preferentially exploit the perforin/granzyme pathway in cytotoxic therapies against Ewing sarcoma.
Collapse
Affiliation(s)
- Alfons S K de Hooge
- Department of Pediatrics, Division of Immunology, Haematology, Oncology, Bone Marrow Transplantation and Autoimmune Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
77
|
Abstract
Defects in programmed cell death or apoptosis are major hallmarks of cancer contributing to tumorigenesis, tumor progression, and therapy resistance. In the past decade, many of the pathways leading to apoptosis, as well as the molecular mechanisms blocking the death of tumor cells, have been elucidated. This detailed knowledge of the core apoptosis machinery is now being exploited for translation into novel cancer therapies in order to restore apoptosis induction in tumor cells. Strategies include activation of proapoptotic mediators such as death receptors, tumor protein p53, and second mitochondria-derived activator of caspases (SMAC)/DIABLO as well as inhibition of endogenous apoptosis inhibitors such as IAPs (inhibitor of apoptosis proteins) and BCL-2 (B-cell chronic lymphoid leukemia/lymphoma) proteins. Several approaches employing gene therapy and antisense strategies, recombinant biologics, or classic organic and combinatorial chemistry, have advanced into clinical trials or are already approved. This review looks at recent developments in apoptosis-based cancer therapies and highlights some very promising advances in drug design.
Collapse
Affiliation(s)
- Ute Fischer
- Institute of Molecular Medicine, Heinrich-Heine University, Düsseldorf, Germany.
| | | | | |
Collapse
|
78
|
Wenger T, Mattern J, Penzel R, Gassler N, Haas TL, Sprick MR, Walczak H, Krammer PH, Debatin KM, Herr I. Specific resistance upon lentiviral TRAIL transfer by intracellular retention of TRAIL receptors. Cell Death Differ 2006; 13:1740-1751. [PMID: 16470224 DOI: 10.1038/sj.cdd.4401867] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in many transformed cells, suggesting TRAIL as an ideal candidate for cancer gene therapy. A main obstacle in cancer therapy is intrinsic or acquired therapy resistance of malignant cells. To study induction of resistance against TRAIL, we generated lentiviral vectors allowing efficient TRAIL expression and apoptosis induction in a variety of human cancer cell lines. Within days upon TRAIL overexpression, cells became resistant towards TRAIL, but not to CD95 ligation or DNA damage by cisplatin. Cell surface expression of TRAIL receptors 1 and 2 was completely abrogated in resistant cells due to intracellular retention of the receptors by TRAIL. SiRNA directed against TRAIL resensitized the resistant cells by restoring cell surface expression of TRAIL receptors. These findings represent a novel resistance mechanism towards TRAIL, specifically caused by TRAIL overexpression, and question the use of TRAIL expression in tumor-cell targeting gene therapy.
Collapse
MESH Headings
- Apoptosis
- Apoptosis Regulatory Proteins/antagonists & inhibitors
- Apoptosis Regulatory Proteins/genetics
- Base Sequence
- Cell Line, Tumor
- Cisplatin/pharmacology
- Death Domain Receptor Signaling Adaptor Proteins
- Drug Resistance, Neoplasm
- Endoplasmic Reticulum/metabolism
- Gene Transfer Techniques
- Genetic Therapy/methods
- Genetic Vectors
- Golgi Apparatus/metabolism
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Humans
- Jurkat Cells
- Lentivirus/genetics
- Membrane Glycoproteins/antagonists & inhibitors
- Membrane Glycoproteins/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- RNA, Small Interfering/genetics
- Receptors, TNF-Related Apoptosis-Inducing Ligand
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Signal Transduction
- TNF-Related Apoptosis-Inducing Ligand
- Transduction, Genetic
- Tumor Necrosis Factor Receptor-Associated Peptides and Proteins/metabolism
- Tumor Necrosis Factor-alpha/antagonists & inhibitors
- Tumor Necrosis Factor-alpha/genetics
Collapse
Affiliation(s)
- T Wenger
- Research Group Molecular Urooncology, German Cancer Research Center, Heidelberg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
79
|
Kondo G, Iwase M, Watanabe H, Uchida M, Takaoka S, Ohashi M, Nagumo M. Enhancement of susceptibility to Fas-mediated apoptosis in oral squamous cell carcinoma cells by phosphatidylinositol 3-kinase inhibitor. Oral Oncol 2006; 42:745-52. [PMID: 16527514 DOI: 10.1016/j.oraloncology.2005.11.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 11/24/2005] [Indexed: 10/24/2022]
Abstract
In general, oral squamous cell carcinoma (OSCC) cells are relatively resistant to Fas-mediated apoptosis during in vitro culture. Here, we studied the role of survival/apoptosis associated phosphatidylinositol 3-kinase (PI 3-K)/Akt in this process. We found that both PI 3-K inhibitors, wortmannin and LY294002, markedly suppressed the phosphorylation of Akt and accelerated Fas-mediated apoptosis in OSCC cells. It was found that caspase-3 and -8 inhibitors reduced the accelerative effect of PI 3-K inhibitor on Fas-mediated apoptosis in OSCC cells, but not caspase-9 inhibitor. Although PI 3-K inhibitors did not affect the Fas expression of OSCC cells, cellular FLICE-inhibitory protein (c-FLIP) levels were markedly reduced by PI 3-K inhibitor treatment. Moreover, antisense oligonucleotide to c-FLIP confirmed that the down-regulation of c-FLIP enhanced the sensitization to Fas-mediated apoptosis in OSCC cells. These results suggest that PI 3-K/Akt signaling pathway may, in part, regulate Fas-mediated apoptosis in OSCC cells through c-FLIP expression.
Collapse
Affiliation(s)
- Gen Kondo
- Department of Oral and Maxillofacial Surgery, Showa University School of Dentistry, 2-1-1, Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan
| | | | | | | | | | | | | |
Collapse
|
80
|
Abstract
Apoptosis mediated via extrinsic or intrinsic pathways is essential for maintaining cellular homeostasis in the liver. The extrinsic pathway is triggered from the cell surface by engagement of death receptors as CD95, TRAIL (TNF-related apoptosis inducing ligand) and TNF (tumour necrosis factor) or TGF-beta (transforming growth factor beta) receptors. The intrinsic pathway is initiated from the mitochondria and can be influenced by Bcl-2 family members. Both pathways are intertwined and play a physiological role in the liver. Dysregulation of apoptosis pathways contributes to diseases as hepatocellular carcinoma, viral hepatitis, autoimmune hepatitis, ischaemia-reperfusion injury, iron or copper deposition disorders, toxic liver damage and acute liver failure. The apoptosis defects are often central pathogenetic events; hence molecular mechanisms of apoptosis give not only insight into disease mechanisms but also provide potential corresponding therapeutic candidates in liver disease. The focus of this review is the identification of apoptotic signalling components in the liver as therapeutic targets.
Collapse
Affiliation(s)
- Sören T Eichhorst
- Ludwig-Maximilians-University, University Hospital Grosshadern, Department of Internal Medicine II, Research Lab B 5 E01 308, Marchioninistrasse 15, D-81377 Munich, Germany.
| |
Collapse
|
81
|
Liu K, Caldwell SA, Greeneltch KM, Yang D, Abrams SI. CTL adoptive immunotherapy concurrently mediates tumor regression and tumor escape. THE JOURNAL OF IMMUNOLOGY 2006; 176:3374-82. [PMID: 16517705 DOI: 10.4049/jimmunol.176.6.3374] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Tumor escape and recurrence are major impediments for successful immunotherapy. It is well-documented that the emergence of Ag-loss variants, as well as regulatory mechanisms suppressing T cell function, have been linked to inadequate antitumor activity. However, little is known regarding the role of Fas-mediated cytotoxicity by tumor-specific CD8(+) CTL in causing immune evasion of Fas resistant variants during adoptive immunotherapy. In this study, we made use of an adoptive transfer model of experimental lung metastasis using tumor-specific CTL as a relevant immune-based selective pressure, and wherein the Fas ligand pathway was involved in the antitumor response. Surviving tumor cells were recovered and examined for alterations in antigenic, functional, and biologic properties. We showed that diminished susceptibility to Fas-mediated cytotoxicity in vivo was an important determinant of tumor escape following CTL-based immunotherapy. Tumor escape variants (TEV) recovered from the lungs of CTL-treated mice exhibited more aggressive behavior in vivo. However, these TEV retained relevant MHC class I and tumor Ag expression and sensitivity to CTL via the perforin pathway but reduced susceptibility to Fas-mediated lysis. Moreover, TEV were significantly less responsive to eradication by CTL adoptive immunotherapy paradigms as a consequence of increased Fas resistance. Overall, we identified that Fas(low)-TEV emerged as a direct consequence of CTL-tumor interactions in vivo, and that such an altered neoplastic Fas phenotype compromised immunotherapy efficacy. Together, these findings may have important implications for both tumor progression and the design of immunotherapeutic interventions to confront these selective pressures or escape mechanisms.
Collapse
Affiliation(s)
- Kebin Liu
- Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg. 10, 10 Center Drive, Bethesda, MD 20892, USA.
| | | | | | | | | |
Collapse
|
82
|
Gomez GG, Varella-Garcia M, Kruse CA. Isolation of immunoresistant human glioma cell clones after selection with alloreactive cytotoxic T lymphocytes: cytogenetic and molecular cytogenetic characterization. ACTA ACUST UNITED AC 2006; 165:121-34. [PMID: 16527606 PMCID: PMC1447520 DOI: 10.1016/j.cancergencyto.2005.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 07/26/2005] [Accepted: 08/01/2005] [Indexed: 01/01/2023]
Abstract
Intratumoral heterogeneity and genetic instability within gliomas may allow intrinsically immunoresistant (IR) cells to escape alloreactive cytotoxic T lymphocyte (aCTL) cellular immunotherapy. The potential existence of aCTL-resistant variants prompted us to investigate whether cellular immunotherapy resistant glioma models could be isolated. To generate the models, repeated intermittent or continuous selective pressure (ISP or CSP) with multiple aCTL populations was applied to a low-passage glioblastoma cell explant, 13-06-MG, obtained from a patient at initial diagnosis. IL-6 and IL-8 secretion was greater in coincubates of aCTL cells with 13-06-ISP and 13-06-CSP immunoselected cells than those with 13-06-MG parental cells. Initially, the immunoselected cells were less sensitive to aCTL lysis; however, the reduced aCTL-sensitivity was not maintained upon further selection. We therefore isolated IR clones from continuously immunoselected cells (13-06-CSP). The frequency of IR clones was 1-6 cells per 10,000 immunoselected cells. Two clones selected for further study, 13-06-IR29 and 13-06-IR30, resisted aCTL lysis in the absence of immunoselective pressure. Cytogenetic analyses revealed structural anomalies and genomic imbalances unique to the IR clones. Based on these findings, a hypothetical model is proposed that traces the origin of the IR clones to a clonal variant within the 13-06-CSP and 13-06-MG populations.
Collapse
Affiliation(s)
- German G. Gomez
- Department of Pathology, University of Colorado Health Sciences Center, Denver, CO 80262
| | | | - Carol A. Kruse
- Division of Cancer Biology and Brain Tumor Research Program, La Jolla Institute for Molecular Medicine, 4570 Executive Boulevard, Suite 100, San Diego, CA 92121
- * Corresponding author. Tel.: (858) 587-8788 ext. 142; fax: (858) 587-6742. E-mail address: (C.A. Kruse)
| |
Collapse
|
83
|
Sohn D, Totzke G, Essmann F, Schulze-Osthoff K, Levkau B, Jänicke RU. The proteasome is required for rapid initiation of death receptor-induced apoptosis. Mol Cell Biol 2006; 26:1967-78. [PMID: 16479014 PMCID: PMC1430261 DOI: 10.1128/mcb.26.5.1967-1978.2006] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Due to their tremendous apoptosis-inducing potential, proteasomal inhibitors (PIs) have recently entered clinical trials. Here we show, however, that various PIs rescued proliferating tumor cells from death receptor-induced apoptosis. This protection correlated with the stabilization of X-linked IAP (XIAP) and c-FLIP and the inhibition of caspase activation. Together with the observation that PIs could not protect cells expressing XIAP or c-FLIP short interfering RNAs (siRNAs) from death receptor-induced apoptosis, our results demonstrate that PIs mediate their protective effect via the stabilization of these antiapoptotic proteins. Furthermore, we show that once these proteins were eliminated, either by long-term treatment with death receptor ligands or by siRNA-mediated suppression, active caspases accumulated to an even larger extent in the presence of PIs. Together, our data support a biphasic role for the proteasome in apoptosis, as they show that its constitutive activity is crucial for the rapid initiation of the death program by eliminating antiapoptotic proteins, whereas at later stages, the proteasome acts in an antiapoptotic manner due to the proteolysis of caspases. Thus, for a successful PI-based tumor therapy, it is crucial to carefully evaluate basal proteasomal activity and the status of antiapoptotic proteins, as their PI-mediated prolonged stability might even cause adverse effects, leading to the survival of a tumor.
Collapse
Affiliation(s)
- Dennis Sohn
- Institute of Molecular Medicine, University of Düsseldorf, Building 23.12, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | | | | | | | | | | |
Collapse
|
84
|
Abstract
Cellular caspase-8 (FLICE)-like inhibitory protein (cFLIP) was originally identified as an inhibitor of death-receptor signalling through competition with caspase-8 for recruitment to FAS-associated via death domain (FADD). More recently, it has been determined that both cFLIP and caspase-8 are required for the survival and proliferation of T cells following T-cell-receptor stimulation. This paradoxical finding launched new investigations of how these molecules might connect with signalling pathways that link to cell survival and growth following antigen-receptor activation. As discussed in this Review, insight gained from these studies indicates that cFLIP and caspase-8 form a heterodimer that ultimately links T-cell-receptor signalling to activation of nuclear factor-kappaB through a complex that includes B-cell lymphoma 10 (BCL-10), mucosa-associated-lymphoid-tissue lymphoma-translocation gene 1 (MALT1) and receptor-interacting protein 1 (RIP1).
Collapse
Affiliation(s)
- Ralph C Budd
- Immunobiology Program, Department of Medicine, The University of Vermont College of Medicine, Burlington, Vermont 50405, USA
| | | | | |
Collapse
|
85
|
Salon C, Eymin B, Micheau O, Chaperot L, Plumas J, Brambilla C, Brambilla E, Gazzeri S. E2F1 induces apoptosis and sensitizes human lung adenocarcinoma cells to death-receptor-mediated apoptosis through specific downregulation of c-FLIP(short). Cell Death Differ 2006; 13:260-72. [PMID: 16052233 DOI: 10.1038/sj.cdd.4401739] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
E2F1 is a transcription factor that plays a well-documented role during S phase progression and apoptosis. We had previously postulated that the low level of E2F1 in primary lung adenocarcinoma contributes to their carcinogenesis. Here, we show that E2F1 triggers apoptosis in various lung adenocarcinoma cell lines by a mechanism involving the specific downregulation of the cellular FLICE-inhibitory protein short, leading to caspase-8 activation at the death-inducing signaling complex. Importantly, we also provide evidence that E2F1 sensitizes tumor as well as primary cells to apoptosis mediated by FAS ligand or tumor necrosis factor-related apoptosis-inducing ligand, and enhances the cytotoxic effect of T lymphocytes against tumor cells. Finally, we describe the specific overexpression of c-FLIP(S) in human lung adenocarcinomas with low level of E2F1. Overall, our data identify E2F1 as a critical determinant of the cellular response to death-receptor-mediated apoptosis, and suggest that its downregulation contributes to the immune escape of lung adenocarcinoma tumor cells.
Collapse
Affiliation(s)
- C Salon
- 1Groupe de Recherche sur le Cancer du Poumon, INSERM U578, Institut Albert Bonniot, La Tronche Cedex, France
| | | | | | | | | | | | | | | |
Collapse
|
86
|
Valente G, Manfroi F, Peracchio C, Nicotra G, Castino R, Nicosia G, Kerim S, Isidoro C. cFLIP expression correlates with tumour progression and patient outcome in non-Hodgkin lymphomas of low grade of malignancy. Br J Haematol 2006; 132:560-70. [PMID: 16445828 DOI: 10.1111/j.1365-2141.2005.05898.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The present study investigated whether the expression of cellular Fas-associated death domain-like interleukin-1beta-converting enzyme (FLICE) inhibitory protein (cFLIP) conveys prognostic information in non-Hodgkin lymphomas (NHLs). cFLIP expression was quantified by immunohistochemistry and immunofluorescence in biopsy specimens from 86 NHL patients for whom clinical information was available. NHL malignancy was graded as high/intermediate or low according to the World Health Organization Classification of Lymphoid Neoplasms. cFLIP was positive in 23 of 45 high-/intermediate-grade NHLs and in 25 of 41 low-grade NHLs. Negative expression of cFLIP was associated with the presence of apoptotic cells in the tumour mass, regardless of the histotype and of the malignancy grade. In NHLs positive for cFLIP, 11 of 23 (48%) high-/intermediate-grade cases and 18 of 25 (72%) low-grade cases showed a bad outcome. In NHLs negative for cFLIP, only four of 22 (18%) high-/intermediate-grade patients and 12 of 16 (75%) low-grade patients achieved complete remission. All these correlations were statistically significant. The correlation of cFLIP expression with clinical outcome was independent of therapy, whether or not it included anti-CD20 antibody (Rituximab). The present findings strongly indicate that cFLIP is a reliable predictor of tumour progression and clinical prognosis in NHLs of low grade of malignancy.
Collapse
Affiliation(s)
- Guido Valente
- Laboratorio di Anatomia Patologica, Universitá del Piemonte Orientale 'A. Avogadro', Novara, Italy
| | | | | | | | | | | | | | | |
Collapse
|
87
|
Müerköster SS, Lust J, Arlt A, Häsler R, Witt M, Sebens T, Schreiber S, Fölsch UR, Schäfer H. Acquired chemoresistance in pancreatic carcinoma cells: induced secretion of IL-1beta and NO lead to inactivation of caspases. Oncogene 2006; 25:3973-81. [PMID: 16474845 DOI: 10.1038/sj.onc.1209423] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Pancreatic cancer exhibits profound chemoresistance resulting either from pre-existing (intrinsic) mechanisms, or from anticancer drug treatment itself (acquired chemoresistance). To identify molecular alterations leading to acquired chemoresistance, the chemosensitive pancreatic carcinoma cell line PT45-P1 was exposed to low-dose treatment with etoposide for 6 weeks. Afterwards, these cells (PT45-P1res) were much more resistant to high-dose treatment with anticancer drugs than parental cells. Among several differentially expressed genes in PT45-P1res cells, IL-1beta was most significantly upregulated, a finding in line with our previous observation that IL-1beta accounts for intrinsic chemoresistance of pancreatic carcinoma cells. Elevated IL-1beta expression in PT45-P1res cells was confirmed by real-time PCR and ELISA, and treatment with the IL-1 receptor antagonist restored drug-induced apoptosis. The increased IL-1beta secretion was accompanied by an elevated formation of nitric oxide (NO) and a NO-dependent inhibition of the etoposide-induced caspase-3/-7/-8/-9 activity. Caspase activation was restored either by the iNOS inhibitor 1400W, the reducing agent dithiothreitol or the IL-1 receptor antagonist, resulting in greater sensitivity towards anticancer drug treatment. Conversely, IL-1beta or the NO-donor SNAP decreased caspase activation and apoptosis in etoposide-treated PT45-P1 cells. These data confirm IL-1beta and NO as determinants of chemoresistance in pancreatic cancer, and indicate that the intrinsic and acquired chemoresistance rely to some extent on common molecular targets beneficial for improved therapeutical strategies.
Collapse
Affiliation(s)
- S Sebens Müerköster
- Laboratory of Molecular Gastroenterology & Hepatology, 1st Department of Medicine, UKSH, Campus Kiel, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
88
|
Dutton A, Young LS, Murray PG. The role of cellular flice inhibitory protein (c-FLIP) in the pathogenesis and treatment of cancer. Expert Opin Ther Targets 2006; 10:27-35. [PMID: 16441226 DOI: 10.1517/14728222.10.1.27] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Protection from death receptor (DR)-mediated apoptosis has been proposed as an important step in the development of malignancy, enabling tumour cells not only to survive and escape antitumour immune responses, but also to develop resistance to chemotherapy or other cancer treatments. An important regulator of DR-induced death is the cellular FADD-like IL-1beta-converting enzyme inhibitory protein (c-FLIP) which, when overexpressed, can protect tumour cells from apoptosis. This review focuses on the role of c-FLIP as a tumour progression factor, with particular emphasis on recent work from the authors' laboratory concerning the contribution of c-FLIP to the pathogenesis of Hodgkin's lymphoma. The possibility of targeting c-FLIP as an approach to the treatment of cancer and, in particular, Hodgkin's lymphoma is discussed.
Collapse
Affiliation(s)
- Amanda Dutton
- Cancer Research UK Institute for Cancer Studies, Division of Cancer Studies, Department of Pathology, The Medical School, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | | | | |
Collapse
|
89
|
Malinge S, Monni R, Bernard O, Penard-Lacronique V. Activation of the NF-kappaB pathway by the leukemogenic TEL-Jak2 and TEL-Abl fusion proteins leads to the accumulation of antiapoptotic IAP proteins and involves IKKalpha. Oncogene 2006; 25:3589-97. [PMID: 16434962 DOI: 10.1038/sj.onc.1209390] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abnormal activation of tyrosine kinases and of signaling pathways they control plays a critical role in the neoplastic process of human hematopoietic malignancy. The nuclear factor-kappaB (NF-kappaB) pathway is one of the signalings activated by the TEL-Jak2 and TEL-Abl oncoproteins and required for their antiapoptotic activity. To define the signal relay responsible for this activation, we used mouse embryonic fibroblast (MEF) cells and observed that TEL-Jak2- and TEL-Abl-mediated NF-kappaB induction was abolished in cells lacking the IkappaB kinase (IKK)alpha but not in IKKbeta(-/-) cells. Similar observations were performed with oncogenic forms of the FMS-like tyrosine kinase 3 (Flt-3) involved in the pathogenesis of one-third of acute myeloid leukemias. Rescue of TEL-Jak2-mediated NF-kappaB activation was obtained with a kinase-proficient form of IKKalpha in IKKalpha(-/-) MEF. Hematopoietic cells transformed by TEL-Jak2 and TEL-Abl showed sustained IKKalpha activity without promotion of NF-kappaB2/p100 processing, generally associated to IKKalpha functions. Furthermore, IAP1, IAP2 and XIAP, which are central regulators of the NF-kappaB-mediated survival pathway, were highly expressed in cells transformed by these oncoproteins. Our results indicate that these oncogenic tyrosine kinases preferentially use an IKKalpha-dependent mechanism to induce a persistent NF-kappaB activity and allow the production of antiapoptotic effectors that participate to their leukemogenic properties.
Collapse
Affiliation(s)
- S Malinge
- EMI 0210, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, Paris, France
| | | | | | | |
Collapse
|
90
|
Krueger A, Fas SC, Giaisi M, Bleumink M, Merling A, Stumpf C, Baumann S, Holtkotte D, Bosch V, Krammer PH, Li-Weber M. HTLV-1 Tax protects against CD95-mediated apoptosis by induction of the cellular FLICE-inhibitory protein (c-FLIP). Blood 2006; 107:3933-9. [PMID: 16403915 DOI: 10.1182/blood-2005-06-2567] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The HTLV-1 transactivator protein Tax is essential for malignant transformation of CD4 T cells, ultimately leading to adult T-cell leukemia/lymphoma (ATL). Malignant transformation may involve development of apoptosis resistance. In this study we investigated the molecular mechanisms by which HTLV-1 Tax confers resistance toward CD95-mediated apoptosis. We show that Tax-expressing T-cell lines derived from HTLV-1-infected patients express elevated levels of c-FLIP(L) and c-FLIP(S). The levels of c-FLIP correlated with resistance toward CD95-mediated apoptosis. Using an inducible system we demonstrated that both resistance toward CD95-mediated apoptosis and induction of c-FLIP are dependent on Tax. In addition, analysis of early cleavage of the BH3-only Bcl-2 family member Bid, a direct caspase-8 substrate, revealed that apoptosis is inhibited at a CD95 death receptor proximal level in Tax-expressing cells. Finally, using siRNA we directly showed that c-FLIP confers Tax-mediated resistance toward CD95-mediated apoptosis. In conclusion, our data suggest an important mechanism by which expression of HTLV-1 Tax may lead to immune escape of infected T cells and, thus, to persistent infection and transformation.
Collapse
Affiliation(s)
- Andreas Krueger
- Tumorimmunology Program, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
91
|
Gomez GG, Kruse CA. Mechanisms of malignant glioma immune resistance and sources of immunosuppression. GENE THERAPY & MOLECULAR BIOLOGY 2006; 10:133-146. [PMID: 16810329 PMCID: PMC1474813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
High grade malignant gliomas are genetically unstable, heterogeneous and highly infiltrative; all characteristics that lend glioma cells superior advantages in resisting conventional therapies. Unfortunately, the median survival time for patients with glioblastoma multiforme remains discouraging at 12-15 months from diagnosis. Neuroimmunologists/oncologists have focused their research efforts to harness the power of the immune system to improve brain tumor patient survival. In the past 30 years, small numbers of patients have been enrolled in a plethora of experimental immunotherapy Phase I and II trials. Some remarkable anecdotal responses to immune therapy are evident. Yet, the reasons for the mixed responses remain an enigma. The inability of the devised immunotherapies to consistently increase survival may be due, in part, to intrinsically-resistant glioma cells. It is also probable that the tumor compartment of the tumor-bearing host has mechanisms or produces factors that promote tumor tolerance and immune suppression. Finally, with adoptive immunotherapy of ex vivo activated effector cell preparations, the existence of suppressor T cells within them theoretically may contribute to immunotherapeutic failure. In this review, we will summarize our own studies with immunotherapy resistant glioma cell models, as well as cover other examined immunosuppressive factors in the tumor microenvironment and immune effector cell suppressor populations that may contribute to the overall immune suppression. An in-depth understanding of the obstacles will be necessary to appropriately develop strategies to overcome the resistance and improve survival in this select population of cancer patients.
Collapse
Affiliation(s)
- German G. Gomez
- Department of Pathology, University of Colorado Health Sciences Center, Denver, CO 80262, USA
| | - Carol A. Kruse
- Division of Cancer Biology and Brain Tumor Research Program, La Jolla Institute for Molecular Medicine, San Diego, CA 92121, USA
| |
Collapse
|
92
|
Abstract
The membrane-bound death ligands CD95L/FasL and TRAIL, which activate the corresponding death receptors CD95/Fas, TRAILR1 and TRAILR2, induce apoptosis in many tumour cells, but can also elicit an inflammatory response. This chapter focuses on the relevance of CD95L/FasL and TRAIL for the tumour surveillance function of natural killer cells and cytotoxic T-cells and discuss current concepts of utilizing these ligands in tumour therapy.
Collapse
Affiliation(s)
- Harald Wajant
- Department of Molecular Internal Medicine, Medical Polyclinic, University of Wuerzburg, Roentgenring 11, 97070 Wuerzburg, Germany
| |
Collapse
|
93
|
Horak P, Pils D, Kaider A, Pinter A, Elandt K, Sax C, Zielinski CC, Horvat R, Zeillinger R, Reinthaller A, Krainer M. Perturbation of the Tumor Necrosis Factor–Related Apoptosis-Inducing Ligand Cascade in Ovarian Cancer: Overexpression of FLIPL and Deregulation of the Functional Receptors DR4 and DR5. Clin Cancer Res 2005; 11:8585-91. [PMID: 16361541 DOI: 10.1158/1078-0432.ccr-05-1276] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: Epithelial ovarian cancer is the most common cause of mortality from gynecologic malignancies. Due to advanced stage at diagnosis, most patients need systemic treatment in addition to surgery. Tumor necrosis factor (TNF)–related apoptosis-inducing ligand (TRAIL) is a member of the TNF family with a promising toxicity profile and synergistic activity with chemotherapeutic agents.
Experimental Design: We used an arrayed panel of epithelial ovarian cancer tissue to assess the protein expression of TRAIL and the clinically most relevant members of its pathway death receptors 4 and 5 (DR4 and DR5) and the long form of FLICE inhibitory protein (FLIPL).
Results: We could show that a majority (66.2%) of the tumor tissues displayed either reduced DR4/DR5 expression (20.6%), increased FLIPL expression (39.7%), or both (5.9%) as determined by immunohistochemistry. Furthermore, higher TRAIL expression in the surrounding connective tissue but not in the tumor cells is significantly (P < 0.05) linked with favorable overall survival in advanced-stage patients.
Conclusions: Mechanisms to escape the immune surveillance mediated by TRAIL are developed by ovarian cancer cells in a high percentage. TRAIL expression in the ovarian cancer microenvironment has an effect on overall survival. These findings enhance our understanding of ovarian cancer pathology and might be helpful in guiding TRAIL-based therapy in future.
Collapse
Affiliation(s)
- Peter Horak
- Clinical Division of Oncology, Department of Medicine I, University of Vienna, Austria
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
94
|
Abstract
Apoptosis is a highly regulated process of cell deletion and plays a fundamental role in the maintenance of tissue homeostasis in the adult organism. Numerous studies in recent years have revealed that apoptosis is a constitutive suicide programme expressed in most, if not all cells, and can be triggered by a variety of extrinsic and intrinsic signals. Many human diseases can be attributed directly or indirectly to a derangement of apoptosis, resulting in either cell accumulation, in which cell eradication or cell turnover is impaired, or cell loss, in which the apoptotic programme is inadvertently triggered. In addition, defective macrophage engulfment and degradation of cell corpses may also contribute to a dysregulation of tissue homeostasis. An increased understanding of the signalling pathways that govern the execution of apoptosis and the subsequent clearance of dying cells may thus yield novel targets for therapeutic intervention in a wide range of human maladies.
Collapse
Affiliation(s)
- B Fadeel
- Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
| | | |
Collapse
|
95
|
Kuwashima N, Nishimura F, Eguchi J, Sato H, Hatano M, Tsugawa T, Sakaida T, Dusak JE, Fellows-Mayle WK, Papworth GD, Watkins SC, Gambotto A, Pollack IF, Storkus WJ, Okada H. Delivery of dendritic cells engineered to secrete IFN-alpha into central nervous system tumors enhances the efficacy of peripheral tumor cell vaccines: dependence on apoptotic pathways. THE JOURNAL OF IMMUNOLOGY 2005; 175:2730-40. [PMID: 16081851 DOI: 10.4049/jimmunol.175.4.2730] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We tested whether modulation of the CNS-tumor microenvironment by delivery of IFN-alpha-transduced dendritic cells (DCs: DC-IFN-alpha) would enhance the therapeutic efficacy of peripheral vaccinations with cytokine-gene transduced tumor cells. Mice bearing intracranial GL261 glioma or MCA205 sarcoma received peripheral immunizations with corresponding irradiated tumor cells engineered to express IL-4 or GM-CSFs, respectively, as well as intratumoral delivery of DC-IFN-alpha. This regimen prolonged survival of the animals and induced tumor-specific CTLs that expressed TRAIL, which in concert with perforin and Fas ligand (FasL) was involved in the tumor-specific CTL activity of these cells. The in vivo antitumor activity associated with this approach was abrogated by administration of neutralizing mAbs against TRAIL or FasL and was not observed in perforin-/-, IFN-gamma-/-, or FasL-/- mice. Transduction of the tumor cells with antiapoptotic protein cellular FLIP rendered the gene-modified cells resistant to TRAIL- or FasL-mediated apoptosis and to CTL killing activity in vitro. Furthermore, the combination therapeutic regimen was ineffective in an intracranial cellular FLIP-transduced MCA205 brain tumor model. These results suggest that the combination of intratumoral delivery of DC-IFN-alpha and peripheral immunization with cytokine-gene transduced tumor cells may be an effective therapy for brain tumors that are sensitive to apoptotic signaling pathways.
Collapse
MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/genetics
- Adoptive Transfer
- Animals
- Antineoplastic Combined Chemotherapy Protocols/administration & dosage
- Apoptosis/immunology
- Brain Neoplasms/immunology
- Brain Neoplasms/pathology
- Brain Neoplasms/prevention & control
- Cancer Vaccines/administration & dosage
- Cancer Vaccines/genetics
- Cancer Vaccines/immunology
- Cell Line, Tumor
- Cytokines/biosynthesis
- Cytokines/physiology
- Cytokines/therapeutic use
- Cytotoxicity, Immunologic
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Dendritic Cells/transplantation
- Glioma/immunology
- Glioma/pathology
- Glioma/prevention & control
- Injections, Intralesional
- Injections, Intraventricular
- Interferon-alpha/administration & dosage
- Interferon-alpha/genetics
- Interferon-alpha/metabolism
- Lymph Nodes/immunology
- Lymph Nodes/pathology
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Signal Transduction/immunology
- Transduction, Genetic
Collapse
Affiliation(s)
- Naruo Kuwashima
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, PA 15213, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
96
|
Giampietri C, Petrungaro S, Klinger FG, Coluccia P, Paone A, Vivarelli E, Filippini A, De Cesaris P, De Felici M, Ziparo E. c-Flip expression and function in fetal mouse gonocytes. FASEB J 2005; 20:124-6. [PMID: 16263940 DOI: 10.1096/fj.05-4626fje] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Apoptosis is a key mechanism in spermatogenesis, and in testis, most gonocytes degenerate at fetal and postnatal ages to select a cell subset committed to become germ stem cells. The aim of the present study is to investigate mechanisms controlling the massive apoptosis of fetal gonocytes. We evaluated the expression and function of c-Flip, an apoptosis inhibitor known to interfere with the proapoptotic Fas-signaling pathway in a variety of cell types, but never investigated in fetal testis. Expression of c-Flip long isoform (c-FlipL) within fetal testis was localized in gonocytes at 16.5 and 18.5 days post coitum (dpc), both at the mRNA and protein level, while it was weakly expressed or undetectable at earlier stages. Moreover, Fas protein was found in fetal testes at 13.5, 16.5, and 18.5 dpc. Testes at 18.5 dpc, expressing high levels of c-FlipL, were resistant to Fas-induced apoptosis while they became highly sensitive when c-FlipL was inhibited by antisense c-Flip oligos. In addition, there was an inverse relation between gonocyte spontaneous apoptosis sensitivity and c-FlipL levels. Furthermore, caspase-10 activity was inversely related with c-FlipL expression, suggesting that caspase-10 might be a target of c-FlipL. These data represent the first evidence demonstrating c-Flip expression in fetal testes and its role in protecting gonocytes from Fas-dependent apoptosis.
Collapse
Affiliation(s)
- Claudia Giampietri
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Histology and Medical Embryology, University of Rome La Sapienza, Rome, Italy.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
97
|
Chanvorachote P, Nimmannit U, Wang L, Stehlik C, Lu B, Azad N, Rojanasakul Y. Nitric oxide negatively regulates Fas CD95-induced apoptosis through inhibition of ubiquitin-proteasome-mediated degradation of FLICE inhibitory protein. J Biol Chem 2005; 280:42044-50. [PMID: 16246840 DOI: 10.1074/jbc.m510080200] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Stimulation of cell surface Fas (CD95) results in recruitment of cytoplasmic proteins and activation of caspase-8, which in turn activates downstream effector caspases leading to programmed cell death. Nitric oxide (NO) plays a key role in the regulation of apoptosis, but its role in Fas-induced cell death and the underlying mechanism are largely unknown. Here we show that stimulation of the Fas receptor by its ligand (FasL) results in rapid generation of NO and concomitant decrease in cellular FLICE inhibitory protein (FLIP) expression without significant effect on Fas and Fas-associated death domain (FADD) adapter protein levels. FLIP down-regulation as well as caspase-8 activation and apoptosis induced by FasL were all inhibited by the NO-liberating agent sodium nitroprusside and dipropylenetriamine NONOate, whereas the NO synthase inhibitor aminoguanidine and NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (PTIO) had opposite effects, indicating an anti-apoptotic role of NO in the Fas signaling process. FasL-induced down-regulation of FLIP is mediated by a ubiquitin-proteasome pathway that is negatively regulated by NO. S-nitrosylation of FLIP is an important mechanism rendering FLIP resistant to ubiquitination and proteasomal degradation by FasL. Deletion analysis shows that the caspase-like domain of FLIP is a key target for S-nitrosylation by NO, and mutations of its cysteine 254 and cysteine 259 residues completely inhibit S-nitrosylation, leading to increased ubiquitination and proteasomal degradation of FLIP. These findings indicate a novel pathway for NO regulation of FLIP that provides a key mechanism for apoptosis regulation and a potential new target for intervention in death receptor-associated diseases.
Collapse
Affiliation(s)
- Pithi Chanvorachote
- Department of Pharmaceutical Sciences and Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, West Virginia 26506, USA
| | | | | | | | | | | | | |
Collapse
|
98
|
Chen HX, Liu YJ, Zhou XD, Luo RY. Expression of cellular FLICE/caspase-8 inhibitory protein is associated with malignant potential in endometrial carcinoma. Int J Gynecol Cancer 2005; 15:663-70. [PMID: 16014121 DOI: 10.1111/j.1525-1438.2005.00122.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This study aimed to investigate the expression of cellular Fas-associated death domain-like interleukin-1beta-converting enzyme (FLICE)/caspase-8 inhibitory protein (c-FLIP) in endometrial carcinoma and its possible implications. c-FLIP protein was detected in 42 endometrial carcinoma tissues and in 22 normal proliferative endometrial tissues by immunohistochemistry. In addition, c-FLIP messenger ribonucleic acid (mRNA) was evaluated in 20 endometrial carcinomas and in 18 normal proliferative endometria by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) using SYBR Green I(TM). The relationship between c-FLIP protein level and tumor cell proliferation and that between c-FLIP protein level and clinicopathologic parameters of patients with endometrial carcinoma was analyzed. c-FLIP protein expression was significantly higher in neoplastic tissues than in normal tissues (P < 0.01), and similar result was obtained from RT-PCR analysis of c-FLIP mRNA (P < 0.01). Furthermore, c-FLIP protein was significantly associated with proliferating cell nuclear antigen-labeling index (P < 0.01), clinical stage (P < 0.05), the presence of invasion to > 1/2 myometrium (P < 0.05), and lymph node metastasis (P < 0.01). Multivariate analysis of variance also confirmed the association of c-FLIP with clinical stage (P < 0.05) and with lymph node metastasis (P < 0.05), while its association with myometrial invasion was marginal (P = 0.059). It is concluded that c-FLIP might contribute to the carcinogenesis and aggressiveness of endometrial carcinoma and might be a useful prognostic factor in the tumor.
Collapse
Affiliation(s)
- H-X Chen
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, China
| | | | | | | |
Collapse
|
99
|
Kim K, Ryu K, Ko Y, Park C. Effects of nuclear factor-kappaB inhibitors and its implication on natural killer T-cell lymphoma cells. Br J Haematol 2005; 131:59-66. [PMID: 16173963 DOI: 10.1111/j.1365-2141.2005.05720.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Natural killer/T-cell lymphoma (NKTL) is a highly aggressive disease. Despite the use of various treatment regimens, the prognosis of NKTL is poor, and new treatment strategies need to be determined. Because of the significant survival potential, nuclear factor (NF)-kappaB has become one of the major targets for drug development. In this study, we explored the effect and action mechanism of NF-kappaB inhibitors, BAY 11-7082 and curcumin, on NKTL cell lines (NKL, NK-92 and HANK1). Electrophoretic mobility shift assay showed that NF-kappaB was constitutively active in HANK1, a chemoresistant cell line. BAY 11-7082 and curcumin suppressed NF-kappaB activation in a time- and dose-dependent manner, which finally resulted in cell death. BAY 11-7082- and curcumin-induced cell death was associated with downregulation of Bcl-xL, cyclin D1, XIAP and c-FLIP, followed by caspase-8, poly(ADP-ribose) polymerase cleavage and activation. Given that the chemoresistant NK-92 cells respond to NF-kappaB inhibitors but not to conventional drugs, BAY 11-7082 and curcumin could be potentially useful for achieving improved outcome in chemotherapy-refractory NKTL.
Collapse
Affiliation(s)
- Kihyun Kim
- Department of Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | | | | | | |
Collapse
|
100
|
Boonman ZFHM, van Mierlo GJD, Fransen MF, de Keizer RJW, Jager MJ, Melief CJM, Toes REM. Maintenance of Immune Tolerance Depends on Normal Tissue Homeostasis. THE JOURNAL OF IMMUNOLOGY 2005; 175:4247-54. [PMID: 16177064 DOI: 10.4049/jimmunol.175.7.4247] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ags expressed at immune privileged sites and other peripheral tissues are able to induce T cell tolerance. In this study, we analyzed whether tolerance toward an intraocular tumor expressing a highly immunogenic CTL epitope is maintained, broken, or reverted into immunity in the event the anatomical integrity of the eye is lost. Inoculation of tumor cells into the anterior chamber of the eye of naive B6 mice leads to progressive intraocular tumor growth, an abortive form of CTL activation in the tumor-draining submandibular lymph node, and systemic tolerance as evidenced by the inability of these mice to reject an otherwise benign tumor cell inoculum. Loss of anatomical integrity of the eye as a consequence of phthisis resulted in loss of systemic tolerance and the emergence of effective antitumor immunity against an otherwise lethal tumor challenge. Phthisis was accompanied by dendritic cell maturation and preceded the induction of systemic tumor-specific CTL immunity. Our data show that normal tissue homeostasis and anatomical integrity is required for the maintenance of ocular tolerance and prevention of CTL-mediated immunity. These data also indicate that tissue injury in the absence of viral or microbial infection can act as a switch for the induction of CTL immunity.
Collapse
|