Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of p53 function and caspase 3 activity on the capacity of the antifolate, methotrexate, to promote senescence arrest and apoptotic cell death was investigated in breast tumor cells. In p53 wild-type, but caspase 3 deficient MCF-7 breast tumor cells, death of approximately 40% of the cell population was observed immediately after acute exposure to 10 microM methotrexate (the IC80 value for a 2 h drug exposure). There was no evidence of either DNA fragmentation, a sub G0 population or morphological alterations indicative of apoptosis; however, PARP cleavage was detected. Cell death was succeeded by growth arrest for at least 72 h--where arrest was characterized by expression of the senescence marker, beta-galactosidase. The response to methotrexate in MCF-7/E6 cells with attenuated p53 function was also primarily growth arrest--but lacking characteristics of senescence. In contrast, MCF-7 cells which expressed caspase 3 demonstrated a gradual and continuous loss of cell viability and unequivocal morphological evidence of apoptosis. DNA fragmentation indicative of apoptosis was also detected after exposure to methotrexate in p53 mutant MDA-MB231 breast tumor cells which also express caspase 3. Methotrexate-induced both p53 and p21waf1/cip1 in MCF-7 cells within 6 h; however, no significant DNA strand breakage was evident before 18 h, suggesting that the induction of p53 reflects a response to cellular stress other than DNA damage, such as nucleotide depletion. Overall, these studies suggest that the nature of the cellular response to methotrexate depends, in large part, on p53 and caspase function. p53 appears to be required for methotrexate-induced senescence, but not apoptosis, caspase 3 is required for DNA fragmentation and the morphological changes associated with apoptosis, while neither p53 nor caspase 3 are required for methotrexate-induced growth arrest. Furthermore, the senescence phenotype may occur in the absence of direct DNA damage.
 ...
PMID:Influence of p53 and caspase 3 activity on cell death and senescence in response to methotrexate in the breast tumor cell. 1545 Sep 35

Most brain tumors consist of transformed glia cells and are highly vascularized by capillary endothelial cells. The aim of the present study therefore was to deliver pro-apoptotic caspase-3 into malignant C6 glioma and immortalized rBCEC4 brain endothelial cells to induce cell death. Both cell lines were transfected with a reporter protein (beta-galactosidase) using lipid-mediated gene transfer (FuGENE6) or using the novel protein delivery reagent BioPORTER. beta-Galactosidase protein was successfully delivered into both cells, the protein expression peaked around day 2 and was transient. Delivery of caspase-3 induced TUNEL-positive cell death of both cell types. As a control, caspase-3 was also delivered to non-neoplastic primary astrocytes and endothelial cells and induced cell death. In conclusion BioPORTER-protein delivery of pro-apoptotic molecules may provide a potent tool to cause death of the cells in brain tumors, however, this method is limited due to its toxicity to non-malignant cells.
 ...
PMID:Protein delivery of caspase-3 induces cell death in malignant C6 glioma, primary astrocytes and immortalized and primary brain capillary endothelial cells. 1569 Jan 27

Gene therapy may be a promising approach for treatment of brain ischemia. In this study, we examined the effect of postischemic gene transfer of midkine, a heparin-binding neurotrophic factor, using a focal brain ischemia model with the photothrombotic occlusion method. At 90 min after induction of brain ischemia in spontaneously hypertensive rats, a replication-deficient recombinant adenovirus encoding mouse midkine (AdMK, n=7) or a control vector encoding beta-galactosidase (Adbetagal, n=7) was injected into the lateral ventricle ipsilateral to ischemia. At 2 days after ischemia, we determined infarct volume by 2,3,5-triphenyltetrazolium chloride staining. There were no significant differences in cerebral blood flow 1 h after ischemia between AdMK and Adbetagal groups. Infarct volume of AdMK group was 51+/-27 mm3, which was significantly smaller than that of Adbetagal group (86+/-27 mm3, P<0.05). TUNEL-positive and cleaved caspase-3-positive cells in the periischemic area of AdMK-treated rats were significantly fewer than those in Adbetagal-treated rats, suggesting that the reduction of infarct volume by midkine was partly mediated by its antiapoptotic action. Thus, gene transfer of midkine to the ischemic brain may be effective in the treatment of brain ischemia.
 ...
PMID:Postischemic gene transfer of midkine, a neurotrophic factor, protects against focal brain ischemia. 1570 67

Pretreatment of HepG2 and H1299 cells with chloramphenicol rendered the cells resistant to mitomycin-induced apoptosis. Both mitomycin-induced caspase 3 activity and PARP activation were also inhibited. The mitochondrial DNA-encoded Cox I protein, but not nuclear-encoded proteins, was down-regulated in chloramphenicol-treated cells. Cellular levels of the p21(waf1/cip1) protein and p21(waf1/cip1) mRNA were increased through a p53-independent pathway, possibly because of the stabilization of p21(waf1/cip1) mRNA in chloramphenicol-treated cells. The p21(waf1/cip1) was redistributed from the perinuclear region to the cytoplasm and co-localized with mitochondrial marker protein. Several morphological changes and activation of the senescence-associated biomarker, SA beta-galactosidase, were observed in these cells. Both p21(waf1/cip1) antisense and small interfering RNA could restore apoptotic-associated caspase 3 activity, PARP activation, and sensitivity to mitomycin-induced apoptosis. Similar effects were seen with other antibiotics that inhibit mitochondrial translation, including minocycline, doxycycline, and clindamycin. These findings suggested that mitochondrial stress causes resistance to apoptosis through a p21-dependent pathway.
 ...
PMID:Chloramphenicol-induced mitochondrial stress increases p21 expression and prevents cell apoptosis through a p21-dependent pathway. 1590 68

This study investigated the anticancer activity and related mechanisms of neolignans, especially threo, erythro-manassantin A (compound 2), which are isolated from Saururus chinensis, in PC-3 cells. Compound 2 strongly inhibited the proliferation of PC-3 cells in a dose-dependent manner. Different cell morphologies were observed depending on the concentration of compound 2, which suggested different growth inhibitory mechanisms. DNA flow cytometry indicated that both low and high concentrations of compound 2 induced the arrest of PC-3 cells in G1 phase. Western blot analyses showed that hyperphosphorylated Rb and E2F-1 were decreased, whereas hypophosphorylated Rb was increased. The cells treated with compound 2 at 200 ng/ml showed shrinkage morphologically, and the staining of annexin V-FITC revealed apoptotic cell death of these cells. The induction of apoptosis was accompanied by the cleavage of caspase-3, -8, and -9, as well as the downregulation of the Bcl-2 and the upregulation of Bax. By contrast, at low compound 2 concentration (1 ng/ml), the cells arrested in G1 showed characteristic changes in morphology, such as an enlarged, flattened cell shape; the majority strongly expressed SA-beta-galactosidase activity. The number of cells undergoing apoptosis was negligible, and no poly(ADP-ribose) polymerase (PARP) cleavage was observed. The increase of p21 was noticed. However, it appeared to be transient rather than sustained. The protein p27 may be important for maintaining the senescence machinery induced by compound 2 because p27 expression was increased at low concentration compared with that at high concentration. In conclusion, compound 2 showed a significant growth inhibitory effect in PC-3 cells via two different mechanisms, i.e., apoptosis at high concentration and senescence at low concentration.
 ...
PMID:Neolignans from Saururus chinensis inhibit PC-3 prostate cancer cell growth via apoptosis and senescence-like mechanisms. 1614 81

Activation of nuclear factor-kappaB (NF-kappaB) can promote or inhibit apoptosis. Oxidative stress is an important mechanism by which certain anticancer drugs kill cancer cells, and is also one of the mechanisms that activate NF-kappaB. We therefore examined hepatic expression of the NF-kappaB monomer p65 in human hepatocellular carcinoma (HCC) tissue samples from eight patients and compared it with their respective samples of surrounding liver tissues. We also studied the effect of NF-kappaB inhibition in human HCC cells exposed to oxidative stress, by infecting HuH7 cells with a recombinant adenovirus carrying mutant IkappaBalpha (mIkappaBalpha). Cultured HuH7 cells were infected with mIkappaBalpha or beta-galactosidase (beta-Gal) for 24 hr followed by treatment with increasing concentrations of H2O2. Cytotoxicity, NF-kappaB translocation, NF-kappaB DNA binding, cell proliferation, and apoptosis were determined. The monomer p65 was overexpressed in six of eight human HCC tissues. In HuH7 cells, introduction of mIkappaBalpha potently inhibited the translocation, activation, and DNA binding of NF- kappaB. In control (beta-Gal-infected) HuH7 cells, exposure to H2O2 produced a dose-dependent increase in apoptosis, regardless of NF-kappaB status. mIkappaBalpha-mediated inhibition of NF-kappaB activation sensitized HuH7 cells to H2O2-induced inhibition of cell growth, and further promoted cell death. Addition of H2O2 (200-500 microM) to control or mIkappaBalpha-infected HuH7 cells enhanced caspase-3 activity and cleavage. Adenovirus-mediated transfer of mIkappaBalpha potently inhibits NF-kappaB activity in HuH7 cells, and this enhances oxidative stress-induced cell killing.
 ...
PMID:Constitutive activation of NF-kappaB in human hepatocellular carcinoma: evidence of a cytoprotective role. 1654 77

Apoptosis plays an important role in maintaining the normal function of various tissues and organs in different species. Caspase-3 is a terminal caspases which plays an important role in the execution of apoptosis in all vertebrates. It was cloned from zebra fish embryos and its properties were identified through Western blotting and biological activity. In the cells over-expressing caspase-3, Western blotting with an anti-His-tag antibody confirmed the presence of caspase-3 in the three bands that were proposed to correspond to the precursor form (33 kDa), the mature forms processed at the prodomain alone (29 kDa, large subunit) and small sub unit (13 kD). Fish kidney cells were transiently co-transfected with the beta-galactosidase reporter gene and either vector alone (mock), pZCASP3His (caspase-3) or pZCASP3His mutant (caspase-3 mutant). After 72 h following transfection of fish kidney cells, 35% of cells transfected with the zebra fish caspase-3 construct, pZCASP3His, showed apoptotic morphology when compared with cells transfected with the mock vector or an expression construct (pZCASP3His mutant) encoding the caspase-3 mutant lacking Cys. The fusion proteins were expressed in Escherichia coli, isolated from cell lysates by nickel-affinity column chromatography, and cleaved with thrombin. A thrombin cleavage recognition site was positioned at the fusion junction to release the caspase-3 from the fusion protein. Phylogenetic analysis showed that the cloned zebra fish caspase was a member of the caspase-3 subfamily with approximately 60% identity with caspase-3 from Xenopus, chicken and mammals. We have obtained structural information by X-ray crystallography. Orthorhombic crystals of the caspase-3 that diffracted to 1.8 A were obtained in a mixture of 0.1 M imidazole (pH 6.0) and 0.4 M NaOAc (pH 7.0 -7.5), containing 30% glycerol. The space group is C222 with cell dimensions of a = 36.07 A, b = 38.80 A, c = 135.20 A.
 ...
PMID:Zebrafish caspase-3: molecular cloning, characterization, crystallization and phylogenetic analysis. 2289 63

West Nile virus (WNV) is a member of the Flavivirus family and induces febrile illness, sporadic encephalitis, and paralysis. The capsid (Cp) of WNV is thought to play a role in inducing these symptoms through caspase-3- and caspase-9-dependent apoptosis. Using WNVCp as bait for a yeast two-hybrid assay, we identified that Hsp70 interacted with WNVCp. The interaction between Hsp70 and WNVCp was further substantiated using purified proteins. Deletion analysis of Hsp70 indicated that WNVCp could bind to the substrate binding domain of Hsp70. The presence of WNVCp in the Hsp70-dependent folding system inhibited the refolding of beta-galactosidase (beta-gal), which showed that WNVCp might function as a negative regulator of Hsp70. Finally, the cytotoxic effect of WNVCp in 293T cells was prevented by ectopic Hsp70, suggesting a negative regulatory role of Hsp70 on WNVCp. Our findings suggest a possible negative regulatory role of Hps70 in the pathway of WNV infection.
 ...
PMID:Hsp70 functions as a negative regulator of West Nile virus capsid protein through direct interaction. 1685 74

A number of studies, mostly performed ex vivo, suggest that lysosomes are involved in apoptosis as a result of a release of their cathepsins into the cytosol. These enzymes could then contribute to the permeabilization of the outer mitochondrial membrane; they could also activate effector caspases. The present study aims at testing whether the membrane of liver lysosomes is disrupted during Fas-mediated cell death of hepatocytes in vivo, a process implicated in several liver pathologies. Apoptosis was induced by injecting mice with aFas (anti-Fas antibody). The state of lysosomes was assessed by determining the proportion of lysosomal enzymes (beta-galactosidase, beta-glucuronidase, cathepsin C and cathepsin B) present in homogenate supernatants, devoid of intact lysosomes, and by analysing the behaviour in differential and isopycnic centrifugation of beta-galactosidase. Apoptosis was monitored by measuring caspase 3 activity (DEVDase) and the release of sulfite cytochrome c reductase, an enzyme located in the mitochondrial intermembrane space. Results show that an injection of 10 microg of aFas causes a rapid and large increase in DEVDase activity and in unsedimentable sulfite cytochrome c reductase. This modifies neither the proportion of unsedimentable lysosomal enzyme in the homogenates nor the behaviour of lysosomes in centrifugation. Experiments performed with a lower dose of aFas (5 microg) indicate that unsedimentable lysosomal hydrolase activity increases in the homogenate after injection but with a marked delay with respect to the increase in DEVDase activity and in unsedimentable sulfite cytochrome c reductase. Comparative experiments ex vivo performed with Jurkat cells show an increase in unsedimentable lysosomal hydrolases, but much later than caspase 3 activation, and a release of dipeptidyl peptidase III and DEVDase into culture medium. It is proposed that the weakening of lysosomes observed after aFas treatment in vivo and ex vivo results from a necrotic process that takes place late after initiation of apoptosis.
 ...
PMID:Lysosomes and Fas-mediated liver cell death. 1712 11

Apoptosis signal-regulating kinase-1 (ASK-1) is an important molecule for the pro-apoptotic signaling. ASK-1 also contributes to the cellular survival for many types of cells. Thus, ASK-1 has a broad range of biological activities depending on the cell type. The present study assessed the role(s) of ASK-1 in colorectal cancer cells (HT-29) by using adenovirus vectors expressing wild-type (WT)-ASK-1 or dominant-negative (DN) mutant of ASK-1 and recombinant adenovirus containing the bacterial beta-galactosidase gene (Ad-LacZ), a negative control for Ad-DN-ASK-1. Selective phosphorylation of ASK-1 at Thr 845, a kinase domain site, but not Ser 83 nor 967 sites was induced by serum stimulation in a time-dependent manner. Transfection with Ad-DN-ASK-1 inhibited the serum-induced phosphorylation of p38 mitogen-activated protein kinase, a downstream molecule of ASK-1. Transfection with Ad-DN-ASK-1 diminished the serum-induced cell proliferation in a dose-dependent manner, whereas WT-ASK-1 increased it. Apoptosis assessed by Hoechst staining was induced in the Ad-DN-ASK-1 treated cells. In vivo transfection of Ad-DN-ASK-1 into tumor xenografts of HT-29 cells in nude mice significantly decreased the tumor volume on day 29. Cleaved caspase-3 was found in the tumors of DN-ASK-1 treated mice. We obtained the first evidence that DN-ASK-1 transfection exerted significant antitumor effects on colon cancer mediated by apoptosis.
 ...
PMID:Growth inhibition of colon cancer cells by transfection of dominant-negative apoptosis signal-regulating kinase-1. 1734 15


<< Previous 1 2 3 4 5 Next >>