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Query: UNIPROT:P42574 (
caspase-3
)
45,978
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Testicular germ cell cancer is one of the very few cancers that are highly sensitive to and curable by cisplatin-based chemotherapy even in an advanced stage. However, in a few cases resistance to cisplatin occurs and patients subsequently die from progressive disease. The molecular basis for this resistance remains to be determined. Using two cisplatin-sensitive (2102EP and H12.1) and one cisplatin-resistant human testicular germ cell cancer cell line (1411HP), we investigated molecular mechanisms in the induction of apoptosis after cisplatin-treatment focusing on the cleavage and activation of
caspase-2
,
caspase-3
, caspase-7, caspase-8, and caspase-9. The cell line 1411HP showed a 3.3-fold cisplatin resistance when compared with the sensitive cell lines 2102EP and H12.1 by IC(90)s, which was treatment schedule independent (2- or 24-h incubation). Cisplatin resistance was associated with substantially decreased apoptosis in vitro and in derived nude mice xenografts as determined by Apo 2.7 detection, DNA-laddering, immunohistochemistry of active
caspase-3
, and terminal deoxynucleotidyl transferase-mediated nick end labeling assay. Total DNA platination as assessed by ELISA after cisplatin treatment in equimolar doses did not differ between cisplatin-resistant or -sensitive cells. In separate analysis of cells of early and late apoptotic stages, initiation of cisplatin-induced apoptosis appeared to be rather mediated by caspase-9 than by caspase-8. Resistant 1411HP cells failed to activate caspase-9 during the induction of apoptosis after cisplatin treatment at the IC(90) dose. Interestingly, inhibition of caspase-9 in sensitive H12.1 almost completely blocked apoptosis and induced cisplatin resistance to the same extent as in 1411HP so that apoptosis could only be induced by 3.3-fold higher cisplatin doses. Furthermore, in caspase-9 blocked cells, initiation of apoptosis occurred in a caspase-9 independent manner accompanied by activation of
caspase-2
and
caspase-3
, which are intrinsic characteristics of resistant 1411HP cells. Failure of caspase-9 activation and cisplatin resistance was independent of the expression of p53, Bcl-2 family proteins, Fas receptor, and Fas ligand. In conclusion, failure of activation of the caspase-9 pathway induces a higher cellular threshold for cisplatin-mediated induction of apoptosis in testicular cancer cells. However, this higher threshold can be overcome by higher cisplatin doses, conceivably by using an alternate, caspase-9-independent apoptotic pathway. This supports the current clinical strategy of high-dose chemotherapy in patients with chemorefractory germ cell tumors. However, additional defining and eventually targeting the exact molecular mechanism blocking caspase-9 activation might lead to more selective therapeutic approaches to overcome cisplatin resistance in germ cell cancer.
...
PMID:Failure of activation of caspase-9 induces a higher threshold for apoptosis and cisplatin resistance in testicular cancer. 1254 10
Histone deacetylase activity is potently inhibited by hydroaximc acid derivatives such as suberoylanilide hydroxamic acid (SAHA) and trichostatin-A (TSA). These inhibitors specifically induce differentiation/apoptosis of transformed cells in vitro and suppress tumor growth in vivo. Because of its low toxicity, SAHA is currently evaluated in clinical trials for the treatment of cancer. SAHA and TSA induce apoptosis, which is characterized by mitochondrial stress, but so far, the critical elements of this apoptotic program remain poorly defined. To characterize in more detail this apoptotic program, we used human cell lines containing alterations in important elements of apoptotic response such as: p53, Bcl-2, caspase-9, and
caspase-3
. We demonstrate that caspase-9 is critical for apoptosis induced by SAHA and TSA and that efficient proteolytic activation of
caspase-2
, caspase-8, and caspase-7 strictly depends on caspase-9. Bcl-2 efficiently antagonizes cytochrome c release and apoptosis in response to both histone deacetylase inhibitors. We provide evidences that translocation into the mitochondria of the Bcl-2 family member Bid depends on caspase-9 and that this translocation is a late event during TSA-induced apoptosis. We also demonstrate that the susceptibility to TSA- and SAHA-induced cell death is regulated by p53.
...
PMID:Role of caspases, Bid, and p53 in the apoptotic response triggered by histone deacetylase inhibitors trichostatin-A (TSA) and suberoylanilide hydroxamic acid (SAHA). 1255 48
Reactive oxygen species (ROS) have been implicated in the pathophysiology of many neurologic disorders and brain dysfunction. In the same pathological settings evidence has been provided in favour of a participation of intracellular Ca(2+) concentration altered homeostasis in the chain of events leading to neuronal apoptosis. In the present review literature reports and experimental data on the relationship between caspase activation and alteration of intracellular calcium concentrations in the mechanisms triggering neuronal apoptosis are discussed. The data gathered support the conclusion that during oxidative stress in neuronal cells the production of ROS triggers a mechanism that, through the release of cytochrome c from mitochondria and
caspase-3
activation, leads to apoptosis; the concomitant ROS-mediated elevation of intracellular Ca(2+) concentration triggers
caspase-2
activation but both events do not seem to be involved in cell death.
...
PMID:Apoptosis induced in neuronal cells by oxidative stress: role played by caspases and intracellular calcium ions. 1262 48
It has been difficult to assign
caspase-2
to the effector or initiator caspase groups. It bears sequence homology to initiators (caspase-9 and CED-3), but its cleavage specificity is closer to the effectors (
caspase-3
and -7). Interest in
caspase-2
was dampened by the lack of a dramatic phenotype in the
caspase-2
null mouse. Studies have been inhibited by the lack of knowledge about its mechanism of activation and the lack of specific methods to assay its activity. Molecular studies have defined a unique role for
caspase-2
in apoptosis initiated by beta-amyloid toxicity or by trophic factor deprivation. Recently, a role for
caspase-2
as an upstream initiator of mitochondrial permeabilization has been proposed. Thus, while much remains to be deciphered about
caspase-2
, most critically the mode of activation, it is clear that
caspase-2
plays critical and singular roles in the control of programmed cell death.
...
PMID:Caspase-2 redux. 1265 98
Lesions in the parkin gene cause early onset Parkinson's disease by a loss of dopaminergic neurons, thus demonstrating a vital role for parkin in the survival of these neurons. Parkin is inactivated by caspase cleavage, and the major cleavage site is after Asp126. Caspases responsible for parkin cleavage were identified by several experimental paradigms. Transient coexpression of caspases and wild type parkin in HEK-293 cells identified caspase-1, -3, and -8 as efficient inducers of parkin cleavage whereas
caspase-2
, -7, -9, and -11 did not induce cleavage. A D126A parkin mutation abrogates cleavage induced by caspase-1 and -8, but not by
caspase-3
. In anti-Fas-treated Jurkat T cells, parkin cleavage was inhibited by caspase inhibitors hFlip and CrmA (but not by X-linked inhibitor of apoptosis (XIAP)), indicating that caspase-8 (but not
caspase-3
) is responsible for the parkin cleavage in this model. Moreover, induction of apoptosis in
caspase-3
-deficient MCF7 cells, either by caspase-1 or -8 overexpression or by tumor necrosis factor-alpha treatment, led to parkin cleavage. These results demonstrate that caspase-1 and -8 can directly cleave parkin and suggest that death receptor activation and inflammatory stress can cause loss of the ubiquitin ligase activity of parkin, thus causing accumulation of toxic parkin substrates and triggering dopaminergic cell death.
...
PMID:Caspase-1 and caspase-8 cleave and inactivate cellular parkin. 1269 30
Programmed cell death (PCD) is a fundamental process regulating immune homeostasis. During acute viral infections PCD of lymphocytes by apoptosis is necessary for removing the excess of activated antigen-reactive T cells and down-regulation of the immune response. On the other hand, apoptosis is the key mechanism of elimination of viral-infected cells. At the present time there is virtually no data on mechanisms of immune regulation during human hantavirus infections. In this study we examined the dynamic of PBL Fas and FasL expression, the first-step dead caspase-8, -2, -9 and effector
caspase-3
, -7 and -10 activity in freshly isolated PBL lysates, and anti-CD3-induced PBL mitogenic response and apoptosis in patients with Puumala virus (PUUV) associated hemorrhagic fever with the renal syndrome (HFRS). Data reported summarize the initial demonstration of increased Fas/FasL and activation of the initializing (
caspase-2
, -8 and -9) and the effector
caspase-3
, -7 and -10 in PBML during acute and convalescent phases of the hantavirus infection. The suppressed anti-CD3 mitogenic response and increased anti-CD3-induced apoptosis were also observed. Although more study needs to be done to determine the role of hantavirus and hantavirus induced pathways in PBML apoptosis, our data suggests that the immune system reacts to hantavirus infection, as to many other virus infections, by activation of apoptosis. These reactions of the immune system could be directed to preserve immune homeostasis, developing the most effective immune protection, and to eliminate cells infected with virus.
...
PMID:Lymphocyte Apoptosis during Hemorragic Fever with Renal Syndrome. 1271 53
Both the anticancer agent 2-chloro-2'-deoxy-adenosine (Cladribine) and its derivative 2-chloro-adenosine induce apoptosis of human astrocytoma cells (J Neurosci Res 60:388-400, 2000). In this study, we have analyzed the involvement of caspases in these effects. Both compounds produced a gradual and time-dependent activation of "effector"
caspase-3
, which preceded the appearance of the nuclear signs of apoptosis, suggesting a temporal correlation between these two events. Moreover, the caspase inhibitor N-benzyloxycarbonyl-Val-Ala-dl-Asp-fluoromethylketone (fmk) suppressed both
caspase-3
activation and apoptosis induction. "Initiator" caspase-9 and caspase-8 were only marginally activated at later times in the apoptotic process. Accordingly, at concentrations that selectively inhibit these caspases, neither N-benzyloxycarbonyl-Leu-Glu-His-Asp-fmk nor N-benzyloxycarbonyl-Ile-Glu-Thr-Asp-fmk could prevent adenosine analog-induced cell death. To definitively rule out a role for the caspase-9/cytochrome c-dependent mitochondrial pathway of cell death, neither adenosine analog had any effect on mitochondrial membrane potential, which was instead markedly reduced by other apoptotic stimuli (e.g., deoxyribose, NaCN, and betulinic acid). Consistently, although the latter triggered translocation of mitochondrial cytochrome c to the cytoplasm, no cytosolic accumulation of cytochrome c was detected with adenosine analogs. Conversely, 1 to 7 h after addition of either adenosine analog (i.e., before the appearance of
caspase-3
activation),
caspase-2
activity was surprisingly and markedly increased. The selective
caspase-2
inhibitor N-benzyloxy carbonyl-Val-Asp-Val-Ala-Asp-fmk significantly reduced both adenosine analogs-induced
caspase-2
activation and the associated cell death. We conclude that adenosine analogs induce the apoptosis of human astrocytoma cells by activating an atypical apoptotic cascade involving
caspase-2
as an initiator caspase, and effector
caspase-3
. Therefore, these compounds could be effectively used in the pharmacological manipulation of tumors characterized by resistance to cell death via either the mitochondrial or caspase-8/death receptor pathways.
...
PMID:A key role for caspase-2 and caspase-3 in the apoptosis induced by 2-chloro-2'-deoxy-adenosine (cladribine) and 2-chloro-adenosine in human astrocytoma cells. 1276 55
During reproductive life, only a selected few ovarian follicles mature and ovulate, while the vast majority of follicles undergo a degenerative process called atresia. Recent studies have indicated that follicular atresia is mediated through apoptosis of follicular granulosa cells. The objectives of the present study were to determine the time of onset of apoptosis in granulosa cells of preovulatory follicles and to evaluate the consequences of gonadotropin withdrawal on mitogen-activated protein (MAP) kinase activities. Bonnet monkeys (Macaca radiata) undergoing controlled ovarian stimulation cycles were utilized for stimulation of multiple follicles, and granulosa cells were retrieved from preovulatory follicles at 24, 48, 72, and 96 h after stopping gonadotropin treatment. Serum and follicular fluid estradiol concentrations were highest at 24 h but declined precipitously (P < 0.05) to reach the lowest concentrations at 96 h; however, progesterone concentrations during this period did not increase, indicating the absence of luteinization. Quantitative analysis of genomic DNA by 3'-end labeling revealed the presence of low-molecular-weight fragments from 48 h onward, but by agarose gel electrophoresis, DNA laddering could be visualized only after 72 h. Messenger RNA expression for Bax,
caspase-2
, and
caspase-3
increased with the onset of apoptosis. Immunoblot analysis of MAP kinases in lysates of granulosa cells (48-72 h) indicated increased (P < 0.05) levels of phosphorylated extracellular response kinase-1 and -2, Jun N-terminal kinase (JNK)-1 and -2, and p38. However, in vitro kinase assay data indicated that only phospho-JNK and -p38 activities were higher at 72 h compared to 24 h. These results demonstrate that granulosa cells of preovulatory follicles undergo apoptosis and that increased activities of phospho-JNK and -p38 are correlated with apoptosis in the primate.
...
PMID:Determination of onset of apoptosis in granulosa cells of the preovulatory follicles in the bonnet monkey (Macaca radiata): correlation with mitogen-activated protein kinase activities. 1280 82
DBM (dibenzoylmethane) is a minor constituent of licorice that has antimutagenic activity. However, its other biological activities are not well-known. The structurally related beta-diketones hydroxydibenzoylmethane (HDB) and hydroxymethyldibenzoylmethane (HMDB) were able to induce apoptosis in colorectal carcinoma COLO 205 cells. Thus, the effect of structurally related beta-diketones on cell viability, DNA fragmentation, and caspase activity was assessed. The potency of these compounds on these features of apoptosis were in the order of HDB > HMDB > DBM in colorectal carcinoma COLO 205 cells. Here, we found that HDB-induced apoptotic cell death was accompanied by upregulation of cyclin D3, Bax, and p21 and down-regulation of Bcl-X(L), while HDB had no effect on the levels of Bcl-2 and Bad protein. These results indicate that HDB allows caspase-activated deoxyribonuclease to enter the nucleus and degrade chromosomal DNA and induces DFF-45 degradation. It is suggested that HDB-induced apoptosis is triggered by the release of cytochrome c into cytosol, procaspase-9 processing, activation of
caspase-3
and
caspase-2
, degradation of PARP, and DNA fragmentation caused by the caspase-activated deoxyribonuclease through the digestion of DFF-45. The induction of apoptosis by HDB may provide a pivotal mechanism for its cancer chemopreventive action.
...
PMID:Induction of apoptosis by hydroxydibenzoylmethane through coordinative modulation of cyclin D3, Bcl-X(L), and Bax, release of cytochrome c, and sequential activation of caspases in human colorectal carcinoma cells. 1282 33
We demonstrate here that selective activation of endogenous members of the caspase family and cleavage of substrates responsible for the maintenance of nuclear functional and structural integrity are major effectors of antigen receptor (AgR)- and ionomycin-triggered apoptosis in Ramos-Burkitt lymphoma (Ramos-BL) B cells. Ramos-BL B cells express significant proenzyme levels of
caspase-2
, -3, -7 and -8, low levels of caspase-6 and are caspase-1-negative. However, while anti-IgM and ionomycin trigger for significant activation of
caspase-3
, -7 and -8 at 12-16 h and at 4 h post-stimulation respectively, both anti-IgM and ionomycin fail to activate
caspase-2
indicating that AgR- and ionomycin-triggered Ramos-BL B cell apoptosis is mediated by the selective activation of, at least,
caspase-3
, -7 and -8. Anti-IgM triggers for cleavage of the resident nuclear proteins poly(ADP-ribose) polymerase (PARP) at 8 h, lamins B1 and B2 from 12 to 16 h; likewise, ionomycin triggers for degradation of PARP at 2 h, lamins B1 and B2 at 4 h. Signal transduction through CD40 rescues Ramos-BL B cells from AgR- and ionomycin-triggered apoptosis at a very early stage of the apoptotic process by inhibiting both the early cleavage of PARP as well as the activation of
caspase-3
, -7 and -8 and cleavage of lamin B1; CD40-mediated rescue occurs upstream of CD40-induced expression of Bcl-2 and increased expression of Bcl-xL. In such cellular populations subject to regulation through apoptosis, dysregulation of the apoptotic mechanisms can have devastating consequences by contributing to the pathogenesis of malignancy as well as to lymphoproliferative and autoantibody disorders. An understanding of the role played by caspases in the execution of apoptosis may provide insight into the pathogenesis of these disease states and thereby provide targets for novel therapeutic strategy.
...
PMID:Temporal ordering of caspase activation and substrate cleavage during antigen receptor-triggered apoptosis in Ramos-Burkitt lymphoma B cells. 1285 74
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