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Query: UNIPROT:P42574 (
caspase-3
)
45,978
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Cytotoxic T lymphocytes (CTL) can trigger an apoptotic signal through the Fas receptor or by the exocytosis of
granzyme B
and perforin. Caspase activation is an important component of both pathways.
Granzyme B
, a serine proteinase contained in granules, has been shown to proteolytically process and activate members of the caspase family in vitro. In order to gain an understanding of the contributions of caspases 8 and 3 during granule-induced apoptosis in intact cells, we have used target cells that either stably express the rabbitpox virus-encoded caspase inhibitor SPI-2 or are devoid of
caspase 3
. The overexpression of SPI-2 in target cells significantly inhibited DNA fragmentation, phosphatidylserine externalization, and mitochondrial disruption during Fas-mediated cell death. In contrast, SPI-2 expression in target cells provided no protection against granzyme-mediated apoptosis, mitochondrial collapse, or cytolysis, leading us to conclude that SPI-2-inhibited caspases are not an essential requirement for the granzyme pathway. Caspase 3-deficient MCF-7 cells were found to be resistant to CTL-mediated DNA fragmentation but not to CTL-mediated cytolysis and loss of the mitochondrial inner membrane potential. Furthermore, we demonstrate that
granzyme B
directly cleaves the proapoptotic molecule Bid, bypassing the need for caspase 8 activation of Bid. These results provide evidence for a two-pronged strategy for mediating target cell destruction and provide evidence of a direct link between
granzyme B
activity, Bid cleavage, and
caspase 3
activation in whole cells.
...
PMID:Granzyme B short-circuits the need for caspase 8 activity during granule-mediated cytotoxic T-lymphocyte killing by directly cleaving Bid. 1080 22
In Polymyositis (PM) and sporadic Inclusion Body Myositis (s-IBM), the CD8(+) cytotoxic T cells invade the muscle membrane and release perforin and
granzyme B
to induce cell death. Although
granzyme B
is a direct activator of executioner caspases, there is no convincing evidence of apoptosis in the muscle fibers of these patients. To search for an explanation, we examined the muscle expression of the human IAP-Like Protein (hILP), an evolutionarily conserved cell death suppressor, that exerts major anti-apoptotic effects by inhibiting the executioner caspases. Muscle biopsy specimens from patients with inflammatory myopathies and controls were studied with: (a) immunocytochemistry using antibodies against hILP and
caspase-3
in single and double-labeled confocal laser microscopy; (b) immunoblotting of muscle extracts immunoreacted with anti-hILP antibodies; and (c) subcellular fractionation of muscle lysates immunoreacted with antibodies against hILP. We found that hILP is expressed on the sarcolemmal region and co-localizes with dystrophin.
Caspase-3
is undetectable. Subcellular fractionation of the muscle specimens confirmed that hILP is a membrane-associated protein. By immunoblotting, the 57 kD hILP was abundantly expressed in the normal as well as the diseased muscles. We conclude that in s-IBM and PM the expression of hILP, a major cell death suppressor, on the muscle membrane may prevent the induction of apoptosis by the autoinvasive cytotoxic T cells on the cell surface, by inhibiting the caspase activation.
...
PMID:Expression of human IAP-like protein in skeletal muscle: a possible explanation for the rare incidence of muscle fiber apoptosis in T-cell mediated inflammatory myopathies. 1081 76
Hyperimmune response via Fas/Fas-ligand and perforin/granzyme pathways may be essential in pathogenesis of virus-induced fulminant hepatitis. CrmA inhibits activation of caspases and
granzyme B
, suggesting it may block these pathways. We investigated whether CrmA expression would inhibit Fas-associated lethal hepatitis in mice. We successfully generated AxCALNLCrmA, a recombinant adenovirus expressing CrmA gene with a Cre-mediated switching cassette. We increased CrmA expression level in the liver transfected with AxCALNLCrmA (10(9) pfu) by increasing administration dose (10(7)-10(9) pfu) of AxCANCre, a recombinant, adenovirus-expressing Cre gene. Injection of anti-Fas antibody into the control mice rapidly led to animal death due to massive liver apoptosis, while the apoptosis was dramatically reduced in the CrmA-expressed mice. The animal survival increased with an increase of CrmA expression. The formation of active
caspase-3
was markedly inhibited in the crmA-transfected hepatocytes in vitro. These results suggest that crmA is an effective gene that can inhibit immune-related liver apoptosis.
...
PMID:Inhibition of Fas-mediated fulminant hepatitis in CrmA gene-transfected mice. 1087 71
Granzyme B
(GzmB) is a component of cytotoxic lymphocyte granules that can rapidly initiate apoptosis in target cells. While several procaspases are cleaved and activated by GzmB, the absolute requirement of caspase activation for GzmB-induced apoptosis is controversial. In this report, we demonstrate that GzmB can initiate apoptosis in the absence of
caspase-3
activity by directly cleaving DFF45/ICAD to liberate activated DFF40/CAD. DFF45/ICAD cleavage occurs less efficiently in cells that lack
caspase-3
activity, suggesting that the caspases normally amplify the GzmB death signal. DFF45/ICAD-deficient mouse embryo fibroblasts are partially resistant to GzmB-induced death, demonstrating the biological importance of DFF45/ICAD for GzmB-mediated apoptosis.
...
PMID:DFF45/ICAD can be directly processed by granzyme B during the induction of apoptosis. 1089 62
Induction of potent apoptosis is required in cancer therapy. We examined the combination effect of interleukin-2-activated lymphocytes (LAK cells) and anticancer drugs or gamma (gamma)-rays on the induction of apoptosis in an established oral squamous cell carcinoma cell line (OSC-3 cells). By pretreatment of OSC-3 cells with (137)Cs (5 Gy), 5-fluorouracil (5-FU) (0.5 microg/ml) or cis-dichlorodiammine-platinum (CDDP) (5 microg/ml), the activation of bid and
caspase-3
by LAK cells was strongly increased and associated with an enhanced degradation of poly-(ADP-ribose) polymerase (PARP) and/or nuclear mitotic apparatus protein (NuMA) and the increased fragmentation of DNA. The LAK cell-enhanced
caspase-3
activity in the pretreated OSC-3 cells was decreased to approximately 70% and 40% of the control by the addition of Z-AAD-CMK (a
granzyme B
inhibitor) and neutralising monoclonal antibody to Fas antigen (alphaFas-IgG), respectively. The combined treatment-induced DNA fragmentation was suppressed by approximately 20% and 30% of the control by the addition of Z-AAD-CMK and alpha Fas-IgG, respectively, in the co-culture system. While Ac-DEVD-CHO (a
caspase-3
inhibitor) suppressed the DNA fragmentation levels to approximately half and this was similar to the amount of suppression that was obtained by the addition of both alpha Fas-IgG and Z-AAD-CMK. In addition, LAK cell-activated bid may have increased the intracellular reactive oxygen intermediates (ROI) level and induced a decrease of mitochondrial membrane potential. These influences by LAK cells were enhanced when OSC-3 cells were pretreated with each anticancer drug or (137)Cs. Furthermore, the increase of ROI by LAK cells was suppressed by alpha Fas-IgG and Z-AAD-CMK to approximately half the level of the control. These results indicate that anticancer drugs and gamma-rays prime squamous cell carcinoma cells to be susceptible to apoptosis by LAK cells, that LAK cell-induced apoptosis largely depends on the activation of
caspase-3
by the Fas/Fas-ligand signal and
granzyme B
, and that LAK cells induce ROI in the target cells, which is largely mediated by Fas and
granzyme B
.
...
PMID:Enhanced apoptosis of squamous cell carcinoma cells by interleukin-2-activated cytotoxic lymphocytes combined with radiation and anticancer drugs. 1100 May 84
Cell death induction by cytotoxic T lymphocytes (CTLs) is an important thesis for the understanding of tumor immunotherapy. In the current study we investigated the molecular machinery of CTL-induced cell death in human hepatocellular carcinoma cell lines (HCC lines). CTLs prepared from human peripheral blood induced cell death in all tested HCC lines. As the CTL-induced death system, the effectiveness of Fas ligand/Fas and/or Perforin/
Granzyme B
systems has been suggested, whereas cell death induction by CTLs was shown independently on Fas expression in the current study. Using various tetrapeptide inhibitors for caspase and its associated factor, we additionally demonstrated that inhibitors for
caspase 3
(Ac-DEVD-CHO) and caspase 8/
granzyme B
(Ac-IETD-CHO) suppressed CTL-induced cell death, but an inhibitor for Fas-activated serine proteinase, which acts for the
caspase 3
activator, did not, suggesting that CTL-induced cell death was initiated by the Perforin/
Granzyme B
system, rather than the Fas ligand/Fas system. On the basis of our current results, we report here that the Perforin/
Granzyme B
system acts dominantly for the cell death induction of HCC lines.
...
PMID:Cell death induction by CTL: perforin/granzyme B system dominantly acts for cell death induction in human hepatocellular carcinoma cells. 1104 57
Granzyme B
is the prototypic member of the granzymes, a family of trypsin-like serine proteinases localized in the dense cytoplasmic granules of activated natural killer cells and cytotoxic T lymphocytes.
Granzyme B
directly triggers apoptosis in target cells by activating the caspase pathway, and has been implicated in the etiology of rheumatoid arthritis. Human
granzyme B
expressed in a baculovirus system has been crystallized without inhibitor and its structure has been determined to 3.1 A resolution, after considerably improving the diffraction power of the crystals by controlled humidity changes. The
granzyme B
structure reveals an overall fold similar to that found in cathepsin G and human chymase. The guanidinium group of Arg226, anchored at the back of the S1-specificity pocket, can form a salt bridge with the P1-Asp side chain of a bound peptide substrate. The architecture of the substrate binding site of
granzyme B
appears to be designed to accommodate and cleave hexapeptides such as the sequence Ile-Glu-Thr-Asp-/Ser-Gly present in the activation site of pro-
caspase-3
, a proven physiological substrate of
granzyme B
. These
granzyme B
crystals, with fully accessible active sites, are well suited for soaking with small synthetic inhibitors that might be used for a treatment of chronic inflammatory disorders.
...
PMID:Crystal structure of the caspase activator human granzyme B, a proteinase highly specific for an Asp-P1 residue. 1120 55
Apoptosis was detected in different muscular diseases, including severe dystrophin deficiency, but apoptotic mechanisms are not completely described in adult skeletal muscle. Studying patients affected by Duchenne muscular dystrophy (DMD) and by facio-scapulo-humeral dystrophy (FSHD) we showed an increase of apoptotic myonuclei, bax, and bcl-2-positive myofibers. Positive correlation was detected between apoptotic nuclei and bax expression (p < 0.01). Expression of caspases was analyzed by RNase protection. Caspase transcript was not detected in normal skeletal muscles. DMD muscles expressed caspase 8, 3, 5, 2, 7 and
Granzyme B
mRNAs. Low levels of caspase 6, 3, and
Granzyme B
transcripts were detected in FSHD patients. Tissue levels of
caspase 3
protein significantly correlated with apoptotic myonuclei (p < 0.05) and with bax expression (p < 0.01). In all DMD cases the activity of
caspase 3
was increased, while the FSHD samples were heterogeneous. These data indicate that human skeletal muscle fibers. during the dystrophic process, modulate the expression of caspases and that
caspase 3
is involved in myofiber cell death. opening new perspective in the pharmacological treatments of muscular dystrophies, such as the use of caspase inhibitors.
...
PMID:Caspase 3 expression correlates with skeletal muscle apoptosis in Duchenne and facioscapulo human muscular dystrophy. A potential target for pharmacological treatment? 1124 14
Cytotoxic T lymphocytes kill virus-infected and tumor cell targets through the concerted action of proteins contained in cytolytic granules, primarily
granzyme B
and perforin.
Granzyme B
, a serine proteinase with substrate specificity similar to the caspase family of apoptotic cysteine proteinases, is capable of cleaving and activating a number of death proteins in target cells. Despite the ability to engage the death pathway at multiple entry points, the preferred mechanism for rapid induction of apoptosis by
granzyme B
has yet to be clearly established. Here we use time lapse confocal microscopy to demonstrate that mitochondrial cytochrome c release is the primary mode of
granzyme B
-induced apoptosis and that Bcl-2 is a potent inhibitor of this pivotal event. Caspase activation is not required for cytochrome c release, an activity that correlates with cleavage and activation of Bid, which we have found to be cleaved more readily by
granzyme B
than either
caspase-3
or caspase-8. Bcl-2 blocks the rapid destruction of targets by
granzyme B
by blocking mitochondrial involvement in the process.
...
PMID:Granzyme B-mediated apoptosis proceeds predominantly through a Bcl-2-inhibitable mitochondrial pathway. 1127 59
Our objective is to investigate the involvement of granule-mediated apoptosis in the cyclic changes of the endometrium. We demonstrated the localization of CD56, perforin,
granzyme B
and
caspase-3
in the endometrium by immunohistochemistry. We also confirmed the localization of perforin by immuno-electron microscopy, and demonstrated apoptosis in endometrial glandular cells by TdT-mediated dUTP-biotin nick end labeling (TUNEL) and electron microscopy. Uterine CD56-positive natural killer (NK) cells expressed perforin and
granzyme B
in its cytoplasm. Uterine NK cells increased significantly in the endometrial stroma during the secretory phase, and peaked during the late secretory phase. These cells started decreasing in number during the menstrual period. In endometrial glandular cells,
caspase-3
and TUNEL-positive cells increased significantly from the late secretory phase, with apoptosis reaching a peak during the menstrual period. Using electron microscopy, we observed uterine NK cells with chromatin rich, segmented nuclei and intracytoplasmic granules in the stroma obtained from late secretory phase endometria. These cells extended projections to the lining of endometrial glandular cells and attached to form a cell-to-cell contact. In addition, nuclear chromatin was observed to have already cohered and small cytoplasmic organelles were beginning to disappear, suggesting that these endometrial glandular cells were undergoing apoptosis. Utilizing immuno-electron microscopy, intracytoplasmic granules in uterine NK cells were stained with anti-perforin antibody. The findings of this study suggest that granule-mediated apoptosis in endometrial glandular cells induced by NK cells expressing perforin and
granzyme B
may be associated with the onset of menstruation.
...
PMID:Involvement of granule-mediated apoptosis in the cyclic changes of the normal human endometrium. 1132 Oct 47
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