Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.22.36 (caspase-1)
 6,285 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ninety-seven patients with refractory or relapsed acute myelogenous leukemia (AML), median age 37 years, received as salvage therapy a single course of idarubicin 6 mg/m2 as an intravenous (i.v.) bolus daily for 5 days, cytarabine (Ara-C) 600 mg/m2 i.v. for a period of 2 hours daily for 5 days and etoposide (VP-16) 150 mg/m2 for a period of 2 hours daily for 3 days (ICE protocol). Thirty-six patients were primarily resistant to standard inductive therapy with daunorubicin and Ara-C; 50 patients were in first relapse, three patients in second or third relapse, and eight patients in relapse after transplants. Forty-two (43%) out of 97 patients achieved complete remission, 11 patients died of infection or hemorrhage during induction, and 44 patients (45%) had resistant disease. Of the various variables examined, only disease status (i.e. refractory versus relapsed AML) was predictive for a significantly lower response rate. The median remission duration was 16 weeks; the overall median survival was 10 weeks. Nausea, vomiting, and oral mucositis were common but were rarely severe. No patient experienced treatment-related cardiac toxicity. In conclusion, the ICE protocol is a tolerable regimen providing effective antileukemic activity in patients with advanced AML. The evolution of this protocol in previously untreated patients with AML appears indicated.
Leukemia 1993 Feb
PMID:Idarubicin in combination with intermediate-dose cytarabine and VP-16 in the treatment of refractory or rapidly relapsed patients with acute myeloid leukemia. The GIMEMA Cooperative Group. 842 73

Bcl-2 expression is able to confer drug resistance to chemotherapy-induced programmed cell death. Bax, a partner protein of bcl-2 with extensive aminoacid homology, is a promoter of apoptosis. Apparently the equilibrium of bcl-2 and bax hetero- and homodimers is important for the susceptibility of cells for stimuli inducing apoptosis. In this study we determined the role of bcl-2 to bax expression ratio, bcl-xL and ICE expression level for predicting clinical response to chemotherapy in acute myelold leukemia (AML). Bone marrow samples from 14 patients with AML were examined using an immunophosphatase staining method. Initial bone marrow blast portion was over 80% in all cases. Clinical response was defined by bone marrow aspiration 4 weeks after treatment initiation. There was a significant correlation between bcl-2 to bax expression ratio and clinical response (P < 0.005). No patients with a bcl-2/bax ratio >1.0 achieved complete remission after induction therapy. No significant correlation between bcl-2- and p-glycoprotein-expression was observed in this group. Conversely a high expression of ICE indicated a good clinical response (P < 0.01), whereas expression of bcl-xL had no influence on therapeutic success in this group.
Leukemia 1996 Jul
PMID:Association of bcl-2, bax, bcl-xL and interleukin-1 beta-converting enzyme expression with initial response to chemotherapy in acute myeloid leukemia. 865 95

The proto-oncogene bcl-2 and a bcl-2-related gene bcl-x prevent apoptotic cell death induced by various treatments. Although a mechanism has been proposed that involves Bcl-2 activity on reactive oxygen species (ROS), we find that expression of Bcl-2 or Bcl-xL prevents cell death induced by withdrawal of oxygen (hypoxia) and that the cell death does not involve ROS, suggesting that Bcl-2 or Bcl-xL exerts an anti-cell death function by a mechanism other than through regulation of ROS activity. Using electron microscopy, and confocal and non-confocal fluorescence microscopy, we show that hypoxia induces both necrosis and apoptosis. Overexpression of Bcl-2 or Bcl-xL blocks hypoxia-induced apoptosis and, although to a lesser extent, necrosis. The anti-apoptotic proteins Bcl-2 and Bcl-xL effectively inhibit KCN-induced cell death which is characterized by necrotic features including apparently intact chromatin, remarkable mitochondrial swelling with loss of crista structure and loss of plasma membrane integrity. The necrotic cell death is also inhibited by inhibitors of ICE (interleukin-1 beta converting enzyme)(-like) proteases, the common mediators of apoptosis. These results indicate that Bcl-2/Bcl-xL and ICE(-like) proteases modulate both apoptotic and at least some forms of necrotic cell death, suggesting that both cell death pathways involve some common mediators.
Leukemia 1997 Apr
PMID:Bcl-2 and Bcl-xL block apoptosis as well as necrosis: possible involvement of common mediators in apoptotic and necrotic signal transduction pathways. 920 97

The human leukemia cell line, HL60 is very sensitive to various apoptotic stimuli and p53-null. The death-related cysteine proteases of the caspases family play a central role in the execution phase of apoptosis, and we recently reported the importance of serine protease activation in camptothecin-induced apoptotic endonuclease activation in HL60 cells. In the present study, we investigated the role of caspases (ICE/CED-3-related cysteine proteases) and serine proteases in cell death induced by the topoisomerase I inhibitor, camptothecin, in HL60 cells and in a cell-free system. We found that CPP32 is activated during camptothecin-induced apoptosis, and that N-benzyloxycarbony-Val-Ala-Asp (O-methyl) -fluoromethyketone (Z-VAD-fmk), a cell permeable caspase inhibitor blocks all features of apoptosis: morphological changes, cleavage of caspase 3 (CPP32/Yama/Apopain) and poly(ADP-ribose) polymerase, lamin B degradation and DNA fragmentation. However, Z-VAD-fmk and two other ICE/CED-3 inhibitors, YVAD-CHO and DEVD-CHO, were inactive in a cell-free system reconstituted from nuclei of untreated HL60 cells and cytosol from camptothecin-treated cells, suggesting that caspases are not required for endonuclease activation or lamin B cleavage in the cell-free system. By contrast, the serine protease inhibitors, 3,4-dichloroisocoumarin (DCI) and L-1-chloro-3-(4-tosylamido)-4-phenyl-2-butanone tosyl-L-phenylalanine chloromethyl ketone (TPCK), abolished the apoptosis-associated biochemical changes induced by camptothecin both in whole cells and in a cell-free system. DCI also inhibited CPP32 cleavage. Taken together, these results suggest that in HL60 cells, both CPP32 and serine proteases are activated in camptothecin-induced apoptosis.
Leukemia 1997 Aug
PMID:Camptothecin-induced apoptosis in p53-null human leukemia HL60 cells and their isolated nuclei: effects of the protease inhibitors Z-VAD-fmk and dichloroisocoumarin suggest an involvement of both caspases and serine proteases. 926 76

CD95 (Fas/APO-1) is a cell surface receptor able to trigger apoptosis in a variety of cell types. The expression and function of the CD95 antigen on leukemic blasts from 42 patients with B lineage and 53 patients with T lineage acute lymphoblastic leukemia (ALL) were investigated using immunofluorescence staining and apoptosis assays. The CD95 surface antigen was expressed in most ALL cases, with the T lineage ALL usually showing a higher intensity of surface CD95 expression as compared with the B lineage ALL cells (relative fluorescence intensity, RFI: 4.8 +/- 0.47 vs 2.2 +/- 0.23, respectively, P < 0.01). Functional studies disclosed that upon oligomerization by anti-CD95 monoclonal antibodies the CD95 protein was either not able to initiate apoptosis of leukemic cells (75% of cases) or induced low rates of apoptosis (20% of cases). Only in 5% of cases did the apoptosis rate exceed the 20% level of the CD95-specific apoptosis. Most of the CD95-sensitive cases were found among T lineage ALLs (38% of T lineage vs 10% of B lineage ALLs). Overall, the extent of CD95-induced apoptosis did not correlate with the expression level of CD95. Similarly, no significant correlation between expression level and functionality of CD95 in human leukemia cell lines of B and T cell origin could be observed. Bcl-2 protein has been associated with prolonged cell survival and has been shown to block partially CD95-mediated apoptosis, but for ALL cells no correlation between bcl-2 expression and spontaneous or CD95-mediated apoptosis could be found. The results obtained in this study indicate that, despite constitutive expression of CD95, the ALL cells are mainly resistant to CD95-triggering. More detailed investigations of the molecular mechanisms involved in the intracellular apoptotic signal transduction, such as interactions of the bcl-2 and the other members of the bcl-2 family, and functionality of the interleukin-1beta converting enzyme (ICE) like-proteases, may give new insights into key events responsible for the resistance or sensitivity to the induction of apoptosis in acute leukemia.
Leukemia 1997 Aug
PMID:Differential CD95 expression and function in T and B lineage acute lymphoblastic leukemia cells. 926 77

Proteases that are members of the caspase (or interleukin-1beta converting enzyme (ICE)) protease family have been shown to be important mediators of apoptosis induced by Fas activation, neurotrophic factor withdrawal, and detachment from extracellular matrix. In this report we have investigated the potential importance of caspase proteases in apoptosis induced by multiple chemotherapeutic agents. Human T leukemic cells engineered to overexpress the cowpox virus CrmA protein, a direct and specific inhibitor of caspase proteases, were studied for their resistance to 1-beta-D-arabinofurasosyl-cytosine (Ara-C), etoposide (VP-16), doxorubicin (DOX), and cis-dichlorodiammine platinum (CP). Overexpression of CrmA dramatically inhibited drug-induced activation of caspases, as measured by processing of the inactive precursor form of caspase-3 and cleavage of caspase substrate proteins poly(ADP-ribose) polymerase (PARP) and lamin B. CrmA also significantly inhibited the kinetics of cell death induced by each of the four drugs. Moreover, when examined several days or weeks after initial exposure to drug, cultures of CrmA-expressing cells were found to have recovered and repopulated, whereas vector-transfected control cells did not. These studies demonstrate that caspase proteases play an important role in conferring sensitivity to multiple chemotherapy drugs, and that constitutive downmodulation of caspase activities can enhance chemoresistance.
Leukemia 1997 Oct
PMID:Inhibition of caspase proteases by CrmA enhances the resistance of human leukemic cells to multiple chemotherapeutic agents. 932 87

The molecular mechanisms for sensitivity and resistance of tumor cells towards chemotherapy are only partially understood. In chemosensitive leukemias and solid tumors, anticancer drugs have been shown to induce apoptosis. We previously identified activation of the CD95 (APO-1/Fas) receptor/CD95 ligand (CD95/CD95-L) system as a key mechanism for drug-induced apoptosis. Here, we show that therapeutic concentrations of doxorubicin, methotrexate and cytarabine also induce apoptosis via activation of the CD95 system in primary leukemia cells in vivo. CD95-resistant and doxorubicin-resistant leukemia and neuroblastoma cells display cross-resistance for induction of cell death. Down-regulation of CD95 expression was found in drug-resistant and CD95-resistant cell lines. Furthermore, up-regulation of CD95-L, previously shown to mediate drug-induced apoptosis in a variety of tumor cells, was completely blocked in doxorubicin-resistant cells. The prototype caspase (ICE/Ced-3 protease) substrate, poly(ADP-ribose)polymerase (PARP), was cleaved in sensitive, but not in resistant tumor cells following CD95 triggering or drug treatment. Since failure to activate CD95-L was not due to decreased drug uptake or increased drug efflux, non-multi-drug resistance (non-MDR) mechanisms are involved in this type of resistance. These findings suggested that an intact CD95 system plays a key role in determining sensitivity or resistance towards anticancer therapy.
Leukemia 1997 Nov
PMID:Deficient activation of the CD95 (APO-1/Fas) system in drug-resistant cells. 936 15

Coexistence of Philadelphia chromosome (Ph)-negative, primitive hematopoietic progenitor cells with their malignant counterparts in chronic myelogenous leukemia (CML) has been reported. As most of the Ph-negative progenitor cells do not express the HLA-DR antigen, selection of them might be possible. Peripheral blood progenitor cells (PBPC) from eight early chronic phase (CML) patients were mobilized by ICE chemotherapy followed by simultaneous administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and recombinant human interleukin 3 (rhIL-3). PBPCs were collected by leukapheresis in the early phase of hematopoietic recovery after chemotherapy, CD34 selected and cultured in vitro. The content of Ph chromosome-positive cells in leukapheresis products as well as after CD34 enrichment and after in vitro culture was analyzed by interphase fluorescence in situ hybridization (FISH) and RT-PCR. The percentage of Ph chromosome-positive PBPC was reduced after each purification step in almost all samples. A substantial number of PBPC samples were negative for the bcr/abl mRNA rearrangement as analyzed by RT-PCR. The present study demonstrates the feasibility of mobilizing Ph-negative PBPC during the early phase of hematopoietic recovery after ICE chemotherapy and simultaneous administration of rhIL-3 and rhG-CSF.
Leukemia 1998 Mar
PMID:Quality of IL-3 and G-CSF-mobilized peripheral blood stem cells in patients with early chronic phase CML. 952 27

The bcl-2 protein plays an essential role in preventing cell death. Its activity is regulated through association with bcl-2 homologous and nonhomologous proteins and also by serine phosphorylation. We now report that bcl-2 can be proteolytically cleaved towards its N-terminus by a cysteine proteinase present in RL-7 lymphoma cell lysates, yielding a major product of apparent MW 20 kDa, different from the products of bcl-2 cleavage by HIV protease. Moreover, bcl-2 proteins mutated for Asp residues at positions 31 and 34 were efficiently cleaved by RL-7 cell lysates, indicating that this proteolytic activity is distinct from the caspase-3 that cleaves bcl-2 at Asp 34. This bcl-2 cleaving activity is inhibited by E-64 and is therefore distinct from the proteinases of the ICE/Ced-3 family (caspases), whereas reciprocally, ICE (caspase-1) is unable to cleave bcl-2. It is optimally active at pH 5, a feature distinguishing it from calpain, another non-ICE cysteine proteinase which has been associated with apoptosis. This novel bcl-2 cleaving protease, although constitutively present in RL-7 cells and resting peripheral blood lymphocytes (PBL) was upregulated following induction of apoptosis in RL-7 cells or mitogen activation in PBL. The N-terminus of bcl-2 which contains the BH4 domain that binds the kinase Raf-1 and the phosphatase calcineurin is essential for anti-apoptotic activity. Its cleavage might provide a novel post-translational mechanism for regulating bcl-2 function and could amplify ongoing programmed cell death.
Leukemia 1998 Sep
PMID:N-terminus cleavage of bcl-2 by a novel cellular non-ICE cysteine proteinase. 973 98

Myelodysplastic syndromes (MDS) are characterized by abnormal growth of committed progenitors in clonogenic assay, with reduced number of colonies and decreased colony/cluster ratio. It has been suggested that excessive apoptosis is the cause of marrow failure in MDS. We studied the expression of caspase-1 (interleukin-1beta-converting enzyme, ICE) and caspase-3 (CPP32/apopain) in marrow mononuclear cells, and the growth pattern of committed progenitors in a series of 83 MDS cases. The percentage of apoptotic cells as detected by TUNEL technique, and the percentage of caspase-3-positive cells were significantly higher in refractory anemia (RA) and RA with ringed sideroblasts (RAS) than in chronic myelomonocytic leukemia (CMML), refractory anemia with excess of blasts (RAEB) and RAEB in transformation (RAEB-T). Spontaneous growth of CFU-GM was associated with a higher percentage of blasts, and with a lower expression of caspase-3 and caspase-1. The yield of CFU-E, BFU-E, and CFU-GM (in the presence of growth factors) was decreased by comparison to normal marrow, but large individual differences were observed in all cytological categories. Inhibition of caspase-1 and caspase-3 activities by specific inhibitors resulted in a significant increase of the production of all types of colonies (up to 50-fold of control). In the presence of caspase-3 inhibitor, the number of BFU-E and CFU-E was in the range of normal values in most cases of RA and RAS. In addition, caspase-1 and -3 protease activities were detectable by fluorogenic assay in all cases studied. Western blot analysis confirmed the expression of caspase-3, including the cleaved (activated)-p17 form in most cases of RA/RAS analyzed. It is concluded that caspase-3 is implicated in the increased apoptosis observed in MDS and that inhibition of its activity can restore at least partially the growth of committed progenitors.
Leukemia 2000 Dec
PMID:Expression and activity of caspases 1 and 3 in myelodysplastic syndromes. 1118 88


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