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1.
Int J Cancer ; 150(6): 1007-1017, 2022 03 15.
Article in English | MEDLINE | ID: mdl-34741530

ABSTRACT

VEGF inhibition in gastric cancer has a proven benefit in the second line setting. Pazopanib, an oral tyrosine kinase inhibitor, selectively inhibits VEGFR-1, -2 and -3, c-kit and PDGF-R resulting in inhibition of angiogenesis. This open-label randomized phase II trial (2:1) investigated the efficacy of combining pazopanib with FLO (5-fluorouracil, oxaliplatin) vs FLO alone (internal control arm) as first-line treatment in patients with advanced adenocarcinoma of the stomach and gastroesophageal junction (GEJ). Eighty-seven patients were randomized and 78 patients were eligible and evaluable (PaFLO arm 51 patients, FLO arm 27 patients). The PFS rate at 6 months (primary endpoint) was 34% in the PaFLO arm vs 30% in the FLO arm. Comparing PaFLO with FLO median PFS was 4.66 months (95% confidence interval [CI] 2.87-6.46) vs 4.47 months (95% CI 1.79-7.14) (95% CI, hazard ratio [HR] 0.96 (0.60-1.55), P = .882 [exploratory]); median OS was 10.19 months (95% CI 5.46-14.92) vs 7.33 months (95% CI 4.93-9.73), (95% CI HR 1.01 [0.62-1.65], P = .953, exploratory), disease control rate was 72% vs 59%. PaFLO was well tolerable, toxicities were slightly higher in the PaFLO arm. Major adverse events were loss of appetite, nausea, fatigue, diarrhea, neutropenia and thrombocytopenia. Adding pazopanib to chemotherapy shows signs of efficacy but no major improvement in this randomized phase 2 trial. The PFS at 6 months in both arms was lower than expected from the literature. Biomarkers identifying subgroups who benefit and novel combinations are needed. ClinicalTrials.gov: NCT01503372.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Stomach Neoplasms/drug therapy , Aged , Esophagogastric Junction/pathology , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Humans , Indazoles/administration & dosage , Indazoles/adverse effects , Male , Middle Aged , Oxaliplatin/administration & dosage , Oxaliplatin/adverse effects , Pyrimidines/administration & dosage , Pyrimidines/adverse effects , Stomach Neoplasms/mortality , Sulfonamides/administration & dosage , Sulfonamides/adverse effects
2.
Oncol Res Treat ; 44 Suppl 1: 1, 2021.
Article in German | MEDLINE | ID: mdl-34344011
3.
Oncol Res Treat ; 43(11): 628-636, 2020.
Article in English | MEDLINE | ID: mdl-33099551

ABSTRACT

BACKGROUND: 5-Fluorouracil (FU) is one of the most commonly used cytostatic drugs in the systemic treatment of cancer. Treatment with FU may cause severe or life-threatening side effects and the treatment-related mortality rate is 0.2-1.0%. SUMMARY: Among other risk factors associated with increased toxicity, a genetic deficiency in dihydropyrimidine dehydrogenase (DPD), an enzyme responsible for the metabolism of FU, is well known. This is due to variants in the DPD gene (DPYD). Up to 9% of European patients carry a DPD gene variant that decreases enzyme activity, and DPD is completely lacking in approximately 0.5% of patients. Here we describe the clinical and genetic background and summarize recommendations for the genetic testing and tailoring of treatment with 5-FU derivatives. The statement was developed as a consensus statement organized by the German Society for Hematology and Medical Oncology in cooperation with 13 medical associations from Austria, Germany, and Switzerland. Key Messages: (i) Patients should be tested for the 4 most common genetic DPYD variants before treatment with drugs containing FU. (ii) Testing forms the basis for a differentiated, risk-adapted algorithm with recommendations for treatment with FU-containing drugs. (iii) Testing may optionally be supplemented by therapeutic drug monitoring.


Subject(s)
Antimetabolites, Antineoplastic/administration & dosage , Dihydrouracil Dehydrogenase (NADP)/genetics , Fluorouracil/administration & dosage , Genetic Testing/methods , Neoplasms/drug therapy , Antimetabolites, Antineoplastic/adverse effects , Austria , Capecitabine/administration & dosage , Capecitabine/adverse effects , Consensus , Female , Fluorouracil/adverse effects , Genetic Testing/standards , Genotype , Germany , Humans , Male , Mutation , Neoplasms/genetics , Phenotype , Practice Guidelines as Topic , Switzerland , Tegafur/administration & dosage , Tegafur/adverse effects
4.
Nucleic Acids Res ; 37(11): e82, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19443447

ABSTRACT

The prediction of transcription factor binding sites in genomic sequences is in principle very useful to identify upstream regulatory factors. However, when applying this concept to genomes of multicellular organisms such as mammals, one has to deal with a large number of false positive predictions since many transcription factor genes are only expressed in specific tissues or cell types. We developed TS-REX, a database/software system that supports the analysis of tissue and cell type-specific transcription factor-gene networks based on expressed sequence tag abundance of transcription factor-encoding genes in UniGene EST libraries. The use of expression levels of transcription factor-encoding genes according to hierarchical anatomical classifications covering different tissues and cell types makes it possible to filter out irrelevant binding site predictions and to identify candidates of potential functional importance for further experimental testing. TS-REX covers ESTs from H. sapiens and M. musculus, and allows the characterization of both presence and specificity of transcription factors in user-specified tissues or cell types. The software allows users to interactively visualize transcription factor-gene networks, as well as to export data for further processing. TS-REX was applied to predict regulators of Polycomb group genes in six human tumor tissues and in human embryonic stem cells.


Subject(s)
Databases, Genetic , Gene Regulatory Networks , Software , Transcription Factors/metabolism , Animals , Binding Sites , Cell Line, Tumor , Embryonic Stem Cells/metabolism , Expressed Sequence Tags , Gene Expression Regulation , Gene Library , Humans , Mice , Neoplasms/genetics , Neoplasms/metabolism , Polycomb-Group Proteins , Repressor Proteins/genetics , Repressor Proteins/metabolism , Transcription Factors/genetics
5.
Curr Opin Investig Drugs ; 9(6): 638-46, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18516763

ABSTRACT

Aegera, under license from Idera Pharmaceuticals, is developing AEG-35156, a 19-mer phosphorothioate antisense oligonucleotide targeting the caspase inhibitor X-linked inhibitor of apoptosis protein (XIAP) messenger RNA, for the potential treatment of cancer. Several clinical trials are ongoing and include: two phase I monotherapy clinical trials for the potential treatment of cancer and in patients with solid tumors; a phase I combination clinical trial of AEG-35156 with docetaxel in locally advanced, metastatic, or recurrent solid tumors; four phase I/II combination clinical trials for the potential treatment of pancreatic cancer, advanced breast cancer, advanced NSCLC, and acute myeloid leukemia. Mild to moderate adverse effects were observed in early phase clinical trials. Aegera plans to initiate randomized phase III trials if tolerable side effects and evidence of activity are demonstrated in phase I/II clinical trials.


Subject(s)
Neoplasms/drug therapy , Oligonucleotides, Antisense/therapeutic use , Oligonucleotides/therapeutic use , X-Linked Inhibitor of Apoptosis Protein/antagonists & inhibitors , X-Linked Inhibitor of Apoptosis Protein/genetics , Animals , Clinical Trials, Phase I as Topic , Clinical Trials, Phase II as Topic , Clinical Trials, Phase III as Topic , Contraindications , Drug Evaluation, Preclinical , Humans , Oligonucleotides/adverse effects , Oligonucleotides/metabolism , Oligonucleotides/pharmacokinetics , Oligonucleotides/pharmacology , Oligonucleotides/toxicity , Oligonucleotides, Antisense/adverse effects , Oligonucleotides, Antisense/metabolism , Oligonucleotides, Antisense/pharmacokinetics , Oligonucleotides, Antisense/pharmacology , Oligonucleotides, Antisense/toxicity , Patents as Topic , Randomized Controlled Trials as Topic , Structure-Activity Relationship
6.
Leuk Res ; 32(7): 1054-60, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18206228

ABSTRACT

Survivin, an inhibitor of apoptosis (IAP) protein plays a dual role in regulation of mitosis and inhibition of apoptosis. Survivin is expressed in embryonic and fetal organs as well as in most human cancers, but not in normal differentiated adult tissues. In this study we investigated the molecular mechanism involved in overexpression of survivin in acute myeloid leukemia (AML). We used methylation specific PCR (MSP) and bisulfite sequencing to analyze the methylation status of the survivin promoter in primary AML samples and normal peripheral blood mononuclear cells (PBMCs). Both, in patients with de novo AML and normal control samples an unmethylated survivin promoter was present. Mutational analysis of the proximal survivin promoter revealed three single nucleotide polymorphisms (SNPs), where the frequently occurred polymorphism (G/C) at position -31 was detectable in both, AML blasts and healthy PBMCs and showed no significant impact on prognosis in de novo AML patients. These results suggest that the methylation status of the survivin promoter and occurrence of these SNPs within the promoter region of the survivin gene appear to be of minor importance in leukemogenesis.


Subject(s)
Epigenesis, Genetic , Leukemia, Myeloid, Acute/genetics , Microtubule-Associated Proteins/genetics , Neoplasm Proteins/genetics , Promoter Regions, Genetic , Base Sequence , Cell Line, Tumor , DNA Methylation , DNA Primers , Humans , Inhibitor of Apoptosis Proteins , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Polymorphism, Single-Stranded Conformational , Survivin
7.
Int J Cancer ; 122(6): 1278-87, 2008 Mar 15.
Article in English | MEDLINE | ID: mdl-18027854

ABSTRACT

Survivin, a member of the inhibitor of apoptosis protein family, is involved in both, inhibition of apoptosis and regulation of cell division. Because of the tumor-specific expression of survivin, the reduction of its expression is an important therapeutic option in the treatment of malignant diseases. Thus, we analyzed the transcriptional regulation of survivin in order to establish survivin as a target gene for new therapeutic approaches. Here, we describe a novel regulatory region within the survivin promoter. After treatment with phorbol 12-myristate-13-acetate, the early growth response (Egr)-1 transcription factor binds to the sequence 5'GAGGGGGCG 3' within the human survivin promoter in vitro and in entire cells. In reporter-gene assays and overexpression experiments, survivin is downregulated following exogenous expression of wildtype Egr-1. Using p53 wildtype and mutated cell lines, we show that Egr-1 negatively regulates survivin expression and sensitizes cell lines to TRAIL-induced apoptosis.


Subject(s)
Early Growth Response Protein 1/physiology , Gene Expression Regulation/physiology , Microtubule-Associated Proteins/genetics , Neoplasm Proteins/genetics , Transcription, Genetic/physiology , Apoptosis/physiology , Base Sequence , Binding Sites , Cell Line , Cell Line, Tumor , Chromatin Immunoprecipitation , DNA , Early Growth Response Protein 1/metabolism , Electrophoretic Mobility Shift Assay , Humans , Inhibitor of Apoptosis Proteins , Microtubule-Associated Proteins/metabolism , Molecular Sequence Data , Neoplasm Proteins/metabolism , Promoter Regions, Genetic , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Survivin , TNF-Related Apoptosis-Inducing Ligand/physiology
8.
Prog Brain Res ; 162: 137-52, 2007.
Article in English | MEDLINE | ID: mdl-17645918

ABSTRACT

Therapeutical hyperthermia has been considered for cancer therapy since William Coley observed tumour remission after induction of fever by bacterial toxins at the end of the 19th century. Because fever is associated with a variety of immunological reactions, it has been suspected, that therapeutical hyperthermia might also activate the immune system in a reproducible manner and thereby positively influence the course of the disease. During the last decade, new insight has been gained regarding the immunological changes taking place during therapeutic hyperthermia. In this chapter, we review the most relevant data known about the effect of hyperthermia on the immune system with special focus on alterations induced by therapeutical whole-body hyperthermia (WBH) in cancer patients.


Subject(s)
Hyperthermia, Induced/methods , Immune System/physiology , Animals , Humans , Neoplasms/immunology , Neoplasms/therapy
9.
Mol Biotechnol ; 33(3): 221-38, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16946452

ABSTRACT

Nucleic acid molecules have emerged as versatile tools with promising utility as therapeutics for human diseases. The specificity of hybridization of an antisense oligonucleotide (AS ODN) to the target mRNA makes the AS strategy attractive to selectively modulate the expression of genes involved in the pathogenesis of malignant or non-malignant diseases. One AS drug has been approved for local therapy of cytomegalovirus retinitis, and a number of AS ODN are currently tested in clinical trials including ODN that target bcl-2, survivin, and DNA methyltransferase. The clinical studies indicate that AS ODN are well tolerated and may have therapeutic activity. In this overview, we summarize therapeutic concepts, clinical studies, and new promising molecular targets to treat human cancer with AS ODN.


Subject(s)
Neoplasm Proteins/antagonists & inhibitors , Neoplasms/drug therapy , Oligonucleotides, Antisense/therapeutic use , Clinical Trials as Topic , Cytomegalovirus Retinitis/drug therapy , Cytomegalovirus Retinitis/genetics , Humans , Neoplasm Proteins/genetics , Neoplasms/genetics , Oligonucleotides, Antisense/genetics
10.
Int J Cancer ; 119(6): 1291-7, 2006 Sep 15.
Article in English | MEDLINE | ID: mdl-16619249

ABSTRACT

Survivin, a member of the inhibitor of apoptosis protein family, is expressed in most human cancers, but undetectable in normal differentiated adult tissue in vivo. Because of this cancer-related expression, survivin is a promising target for cancer therapy. To determine the expression and prognostic role of survivin in acute myeloid leukemia (AML), we investigated the mRNA expression pattern of survivin and of the splice variants survivin-2B and survivin-DeltaEx3 in adult (n = 74) and children (n = 31) with de novo AML using RT-PCR. Survivin was the predominant transcript variant in AML cells, whereas significantly lower levels of survivin-2B and survivin-DeltaEx3 were observed (p < or = 0.0001). Neither expression of survivin nor of any splice variant correlated with maturation stage (FAB subtypes, immunophenotype) or cytogenetic risk groups. For AML cases treated according to AMLCG92 (adult) and AML-BFM93 (children) protocols, respectively, expression patterns were correlated with clinical data: in adult AML (n = 51), low expression of survivin-2B correlated with a better overall survival (p = 0.05; mean survival time 19 months vs. 9 months) and a better eventfree survival (p < or = 0.01; 27 months vs. 10 months). In childhood AML (n = 31), high survivin-DeltaEx3 expression was associated with a shorter overall survival (p < or = 0.05; 24 months vs. 43 months). We conclude that certain survivin splice variants have potential prognostic impact for long-term therapy outcome in adult as well as childhood de novo AML.


Subject(s)
Alternative Splicing , Leukemia, Myeloid/metabolism , Microtubule-Associated Proteins/metabolism , Neoplasm Proteins/metabolism , Acute Disease , Adult , Aged , Apoptosis , Case-Control Studies , DNA, Neoplasm/genetics , DNA, Neoplasm/metabolism , Disease-Free Survival , Female , Humans , Immunophenotyping , Inhibitor of Apoptosis Proteins , Leukemia, Myeloid/diagnosis , Leukemia, Myeloid/genetics , Male , Microtubule-Associated Proteins/genetics , Middle Aged , Neoplasm Proteins/genetics , Neoplasm Staging , Prognosis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Survivin
11.
Clin Sci (Lond) ; 110(4): 427-42, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16526947

ABSTRACT

Preclinical and clinical studies indicate a role for AS ODNs (antisense oligonucleotides) as therapeutics for malignant diseases. The principle of antisense technology is the sequence-specific binding of an AS ODN to the target mRNA, resulting in a translational arrest. The specificity of hybridization makes antisense strategy attractive to selectively modulate the expression of genes involved in the pathogenesis of malignant diseases. One antisense drug has been approved for local therapy of CMV (cytomegalovirus) retinitis, and a number of AS ODNs are currently being tested in clinical trials, including AS ODN targeting Bcl-2, XIAP (X-linked inhibitor of apoptosis protein) and TGF-beta-2 (transforming growth factor beta-2). AS ODNs are well tolerated and may have therapeutic activity. In particular, an AS ODN to Bcl-2 has been tested in phase III clinical trials in chronic lymphocytic leukaemia, multiple myeloma and malignant melanoma. In this review, therapeutic concepts, clinical studies and new promising molecular targets to treat malignancies with AS ODNs are summarized.


Subject(s)
Genetic Therapy/methods , Neoplasms/therapy , Clinical Trials as Topic , Forecasting , Genetic Therapy/trends , Humans , Neoplasm Proteins/genetics , Oligonucleotides, Antisense/therapeutic use , Viral Proteins/genetics , Virus Diseases/therapy
13.
Ann Hematol ; 84 Suppl 1: 47-53, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16193303

ABSTRACT

The demethylating effect of 5-aza-2' deoxycytidine (decitabine, DAC) has been well characterized. The molecular events downstream of methylation inhibition are less well known. Here, DAC was shown to induce apoptosis in acute myeloid leukemia (AML) cells (p53 mutant and wild type) but not in epithelial or normal peripheral blood mononuclear cells. Apoptosis was characterized by activation of the mitochondrial but not the receptor death pathway, as demonstrated by the release of cytochrome c and loss of mitochondrial membrane potential. Western blotting and enzyme assays showed that caspase-3, but not caspase-6 or caspase-8, were activated. Decitabine induced expression of the cell cycle inhibitor p21, arresting AML cell lines in G1 of the cell cycle. Expression of p21 was induced irrespective of the methylation status of its promoter, mediated instead via reexpression of the tumor suppressor p73, an upstream regulator of p21. The promoter of p73 was hypermethylated in AML cell lines in vitro and in primary AML cells ex vivo but not in DAC-resistant epithelial cells. In conclusion, DAC acts on leukemic myeloid cells via caspase activation, which may be dependent on demethylation of the hypermethylated p73 promoter and consequent reexpression of p73.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Azacitidine/analogs & derivatives , Caspase 3/drug effects , DNA-Binding Proteins/drug effects , Leukemia, Myeloid, Acute/drug therapy , Nuclear Proteins/drug effects , Promoter Regions, Genetic/drug effects , Tumor Suppressor Proteins/drug effects , Apoptosis/drug effects , Azacitidine/pharmacology , Caspase 3/metabolism , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p21/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , DNA Methylation/drug effects , DNA-Binding Proteins/metabolism , Decitabine , Enzyme Activation , Humans , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Nuclear Proteins/metabolism , Tumor Protein p73 , Tumor Suppressor Proteins/metabolism
15.
Int J Cancer ; 114(5): 683-95, 2005 May 01.
Article in English | MEDLINE | ID: mdl-15609309

ABSTRACT

The DNA methylation inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR) has significant therapeutic value for the treatment of patients with myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). The demethylating effect of 5-Aza-CdR has been well characterized. In contrast, less is known about the molecular events downstream of the methylation inhibition. Here, 5-Aza-CdR induced apoptosis in AML cells (both p53 mutant and wild-type) but not in epithelial or normal PBMCs. Cell death was accompanied by activation of the mitochondrial apoptosis pathway, as shown by release of cytochrome c and AIF and loss of mitochondrial membrane potential (DeltaPsim). Activation of caspase-3 (but not -6 and -8) was detectable using Western blot analysis and measurement of caspase enzymatic activity. 5-Aza-CdR treatment resulted in the induction of p21, which correlated with the arrest of AML cells in the G1 cell cycle phase. Induction of p21 expression was independent of its promoter methylation status but mediated by 5-Aza-CdR-induced reexpression of the tumor-suppressor p73, a known upstream regulator of p21. The p73 promoter was hypermethylated in AML cell lines and in primary AML cells but not in epithelial cells, which were resistant toward 5-Aza-CdR. Therefore, 5-Aza-CdR-mediated specific killing of myeloid cells might be dependent on its ability to revert p73 promoter methylation and to reexpress p73 mRNA. In addition, exogenous expression of p73 rendered epithelial cells sensitive to apoptosis induced by 5-Aza-CdR or other cytostatic drugs. We therefore conclude that p73 is a relevant target for methylation-dependent efficacy of 5-Aza-CdR in AML cells.


Subject(s)
Apoptosis , Azacitidine/analogs & derivatives , Azacitidine/pharmacology , Cell Cycle Proteins/biosynthesis , DNA Methylation , DNA-Binding Proteins/metabolism , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myeloid, Acute/drug therapy , Myelodysplastic Syndromes/drug therapy , Nuclear Proteins/metabolism , Tumor Suppressor Protein p53/metabolism , Blotting, Western , Caspase 3 , Caspases/metabolism , Cell Cycle , Cell Line, Tumor , CpG Islands , Cyclin-Dependent Kinase Inhibitor p21 , Cytochromes c/metabolism , DNA-Binding Proteins/genetics , Decitabine , Epithelial Cells/cytology , Epithelial Cells/metabolism , Flow Cytometry , G1 Phase , Genes, Tumor Suppressor , HL-60 Cells , HeLa Cells , Humans , Leukocytes, Mononuclear/metabolism , Membrane Potentials , Microscopy, Fluorescence , Mitochondria/metabolism , Nuclear Proteins/genetics , Promoter Regions, Genetic , RNA/chemistry , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sulfites/chemistry , Time Factors , Transfection , Tumor Protein p73 , Tumor Suppressor Proteins , U937 Cells , Up-Regulation
16.
Hematol J ; 5(6): 489-95, 2004.
Article in English | MEDLINE | ID: mdl-15570290

ABSTRACT

Antiapoptotic proteins like the inhibitor of apoptosis proteins (IAPs) are molecular markers potentially useful for the characterization of acute myeloid leukemia (AML). We screened 92 adults with de novo AML for the protein expression of various IAPs, Bcl-2 family members and the proform of Caspase-3 using quantitative immunoblot and flow cytometry. XIAP expression correlated with myelomonocytic French-American-British (FAB) subtypes M4/M5 (P < 0.05) and expression of monocytic markers (CD 14, CD 36; P < 0.05; CD 4, HLA-DR; P < 0.01) in AML blasts. In addition, XIAP was overexpressed in normal monocytes but undetectable in granulocytes. In AML, XIAP expression was significantly lower in patients with favorable than intermediate or poor cytogenetics (n = 74; P < 0.05). In total, 62 of the examined patients were treated according to the German AML Cooperative Group (AMLCG) 92 protocol. These patients were analyzed for prognostic significance of apoptosis-related proteins. Patients expressing low levels of XIAP enjoyed better overall survival than patients expressing high amounts of XIAP (mean, 9 (n = 41) versus 19 months (n = 21); P < 0.05). Other IAPs, most importantly Survivin, were of no prognostic value. We conclude that XIAP but not other IAP family members is associated with monocytic differentiation in normal and malignant myelopoiesis, and may be of prognostic significance for overall survival in adult de novo AML.


Subject(s)
Cell Differentiation/immunology , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/metabolism , Monocytes/metabolism , Proteins/metabolism , Adult , Aged , Antigens, Differentiation/analysis , Antigens, Differentiation/biosynthesis , Caspase 3 , Caspases/biosynthesis , Female , Flow Cytometry , Humans , Image Cytometry , Immunophenotyping , Inhibitor of Apoptosis Proteins , Leukemia, Myeloid, Acute/immunology , Male , Microtubule-Associated Proteins/biosynthesis , Middle Aged , Monocytes/immunology , Monocytes/pathology , Neoplasm Proteins , Predictive Value of Tests , Prognosis , Proteins/analysis , Proto-Oncogene Proteins c-bcl-2/biosynthesis , Risk Factors , Survival Analysis , Survivin , X-Linked Inhibitor of Apoptosis Protein
17.
Oncogene ; 23(40): 6743-59, 2004 Sep 02.
Article in English | MEDLINE | ID: mdl-15273737

ABSTRACT

The Hodgkin cell line HD-MyZ is resistant to apoptosis induced by tumor necrosis factor alpha (TNFalpha). In the present work, we show that pretreatment with TNFalpha sensitized the cells to apoptosis induced by antineoplastic agents and ceramide. TNFalpha pretreatment resulted in enhanced cleavage and activity of caspase-3 upon addition of etoposide, epirubicin or ceramide. No caspase-8 activation was detectable, although caspase-8 could be activated in cell-free extracts. Inhibition of caspase-8 by z-IETD-fmk did not block the sensitizing effect of TNFalpha. Furthermore, exogenous ceramide, a mediator of TNFalpha signaling, could not substitute for TNFalpha in sensitization to drug-induced apoptosis. In contrast, we observed mitochondrial changes following cotreatment of cells with TNFalpha and drugs. Mitochondrial permeability transition, cytochrome c release and subsequent processing of caspase-9 preceded the onset of apoptosis, and were enhanced by TNFalpha pretreatment. Interestingly, although transcription factor NF-kappaB protected HD-MyZ cells from drug-induced apoptosis, TNFalpha-mediated sensitization was independent of NF-kappaB, since overexpressing a dominant-negative IkappaB mutant did not alter the TNFalpha effect. Sensitization for drug-induced apoptosis by TNFalpha was abrogated by Bcl-x(L). Thus, the sensitizing effect of TNFalpha is mediated by the mitochondrial pathway and involves processing of caspase-2, -3 and -9, but appears to be independent of caspase-8 processing, Bid cleavage and NF-kappaB signaling. Therefore, sensitization by TNFalpha is mediated at least in part through different pathways, as reported for TRAIL. There, sensitization occurs through a FADD/caspase-8-dependent mechanism. Regarding TNFalpha, the sensitizing effect was also observed in myeloid leukemia cells. Therefore, TNFalpha or alternate molecules activating its pathways might be useful as sensitizers for chemotherapy in hematological malignancies.


Subject(s)
Antineoplastic Agents/toxicity , Apoptosis/drug effects , Caspases/metabolism , Mitochondria/drug effects , NF-kappa B/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Adult , Blotting, Northern , Caspase 8 , Cell Death/drug effects , Cell Line, Tumor , Ceramides/toxicity , Drug Resistance, Neoplasm , Epirubicin/toxicity , Etoposide/toxicity , Hodgkin Disease , Humans , Intracellular Membranes/drug effects , Intracellular Membranes/physiology , Leukemia, Myeloid , Membrane Potentials/drug effects , Membrane Potentials/physiology , Mitochondria/physiology , Proto-Oncogene Proteins c-bcl-2/drug effects , Proto-Oncogene Proteins c-bcl-2/metabolism , Sphingomyelins/metabolism , bcl-X Protein
18.
Clin Cancer Res ; 10(11): 3737-44, 2004 Jun 01.
Article in English | MEDLINE | ID: mdl-15173080

ABSTRACT

PURPOSE: Apoptosis-related proteins are important molecules for predicting chemotherapy response and prognosis in adult acute myeloid leukemia (AML). However, data on the expression and prognostic impact of these molecules in childhood AML are rare. EXPERIMENTAL DESIGN: Using flow cytometry and Western blot analysis, we, therefore, investigated 45 leukemic cell samples from children with de novo AML enrolled and treated within the German AML-BFM93 study for the expression of apoptosis-regulating proteins [CD95, Bcl-2, Bax, Bcl-xL, procaspase-3, X-linked inhibitor of apoptosis protein (XIAP), cellular inhibitor of apoptosis protein-1 (cIAP-1), survivin]. RESULTS: XIAP (P < 0.002) but no other apoptosis regulators showed maturation-dependent expression differences as determined by French-American-British (FAB) morphology with the highest expression levels observed within the immature M0/1 subtypes. XIAP (P < 0.01) and Bcl-xL (P < 0.01) expression was lower in patients with favorable rather than intermediate/poor cytogenetics. After a mean follow-up of 34 months, a shorter overall survival was associated with high expression levels of XIAP [30 (n = 10) versus 41 months (n = 34); P < 0.05] and survivin [27 (n = 10) versus 41 months (n = 34); P < 0.05]. CONCLUSIONS: We conclude that apoptosis-related molecules are associated with maturation stage, cytogenetic risk groups, and therapy outcome in childhood de novo AML. The observed association of XIAP with immature FAB types, intermediate/poor cytogenetics, and poor overall survival should be confirmed within prospective pediatric AML trials.


Subject(s)
Leukemia, Myeloid, Acute/metabolism , Leukemia, Myeloid, Acute/mortality , Microtubule-Associated Proteins/biosynthesis , Proteins/metabolism , Adolescent , Apoptosis , Blotting, Western , Caspase 3 , Caspases/biosynthesis , Child , Child, Preschool , Female , Flow Cytometry , Humans , Immunophenotyping , Infant , Infant, Newborn , Inhibitor of Apoptosis Proteins , Male , Neoplasm Proteins , Proto-Oncogene Proteins c-bcl-2/biosynthesis , Risk , Survivin , Time Factors , Treatment Outcome , X-Linked Inhibitor of Apoptosis Protein , bcl-2-Associated X Protein , fas Receptor/biosynthesis
19.
Haematologica ; 89(3): 363-4, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15020280

ABSTRACT

Distinct expression patterns of pro- and anti-apoptotic proteins may contribute to different prognoses and therapy outcomes in adult versus childhood acute myeloid leukemia (AML). Therefore, we investigated whether expression levels of apoptosis-related proteins CD95, Bcl-2, Bax, Bcl-xL, procaspase-3, XIAP, cIAP-1, and survivin differ between children and adults with de novo AML.


Subject(s)
Apoptosis Regulatory Proteins/blood , Leukemia, Myeloid/blood , Acute Disease , Child , Humans , Leukemia, Myeloid/diagnosis , Leukemia, Myeloid/therapy , Middle Aged , Prognosis , Retrospective Studies
20.
EMBO J ; 22(11): 2729-40, 2003 Jun 02.
Article in English | MEDLINE | ID: mdl-12773388

ABSTRACT

Survivin is an anti-apoptotic protein that is overexpressed in most human cancers. We show that survivin forms complexes with a cellular protein, hepatitis B X-interacting protein (HBXIP), which was originally recognized for its association with the X protein of hepatitis B virus (HBX). Survivin-HBXIP complexes, but neither survivin nor HBXIP individually, bind pro-caspase-9, preventing its recruitment to Apaf1, and thereby selectively suppressing apoptosis initiated via the mitochondria/cytochrome c pathway. Viral HBX protein also interacts with the survivin- HBXIP complex and suppresses caspase activation in a survivin-dependent manner. Thus, HBXIP functions as a cofactor for survivin, and serves as a link between the cellular apoptosis machinery and a viral pathogen involved in hepatocellular carcinogenesis.


Subject(s)
Apoptosis/physiology , Carrier Proteins/physiology , Hepatitis B virus/pathogenicity , Microtubule-Associated Proteins/physiology , Viral Nonstructural Proteins/physiology , Adaptor Proteins, Signal Transducing , Apoptotic Protease-Activating Factor 1 , Base Sequence , Carcinoma, Hepatocellular/etiology , Caspase 9 , Caspases/metabolism , DNA, Complementary/genetics , Enzyme Activation , HeLa Cells , Hepatitis B/complications , Hepatitis B/physiopathology , Hepatitis B virus/physiology , Humans , In Vitro Techniques , Inhibitor of Apoptosis Proteins , Liver Neoplasms/etiology , Neoplasm Proteins , Phosphorylation , Protein Binding , Proteins/metabolism , RNA, Small Interfering/genetics , Recombinant Fusion Proteins/metabolism , Survivin , Trans-Activators/physiology , Viral Regulatory and Accessory Proteins
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