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

CD95 ligand (CD95L)-induced apoptosis is a novel immunotherapeutic approach to malignant glioma. Here, we report that interferon-alpha (IFN-alpha) sensitizes LN-229 and T98G human malignant glioma cells to CD95L-induced apoptosis. In contrast to the effects of IFN-gamma and TNF-alpha which sensitize glioma cells to CD95 antibody-induced apoptosis in part by enhancing CD95 expression, IFN-alpha has no effect on CD95 expression at the cell surface of LN-229 and T98G cells. To confirm that changes in CD95 expression are not required for the effects of IFN-alpha, we show that IFN-alpha enhances CD95L-induced apoptosis even in CD95-transfected LN-308 glioma cells. These LN-308 cells have little endogenous CD95 expression but express high levels of CD95 from a stably integrated CD95 expression plasmid. The sensitizing effects of IFN-alpha appear to be independent of cell cycle effects of IFN-alpha and are unaffected by ectopic expression of the bcl-2 proto-oncogene. IFN-alpha enhances CD95L-induced activation of caspase-3, a critical mediator of CD95L-induced cell death. IFN-alpha also increases the cytotoxic effects of BCNU, teniposide and cytarabine in both cell lines, and of vincristine in LN-229 cells. Doxorubicin and 5-fluorouracil toxicity are unaffected by IFN-alpha. IFN-alpha may be a useful adjunct to novel strategies of immunochemotherapy for malignant gliomas that target CD95-mediated apoptosis.
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PMID:Interferon-alpha enhances CD95L-induced apoptosis of human malignant glioma cells. 967 Aug 53

Antineoplasic agents such as cisplatin and adriamycin execute their pharmacological role by triggering apoptosis. We have studied the mechanism of apoptosis induction by cisplatin and adriamycin. Both drugs activated JNK with slow and persistent kinetics. Adriamycin activated caspase-3 before the rise in JNK activity, while the response to cisplatin occurs hours after JNK activation. The increase in JNK activity was necessary for cisplatin-mediated apoptosis but it was dispensable for adriamycin-induced cell death. Cells derived from c-jun knock out mice were more resistant to cisplatin cell death than normal cells, but no difference was observed in response to adriamycin. Activation of JNK and cell death by cisplatin is mediated by the MEKK1/SEK1 cascade, since expression of dominant negative expression vectors of these kinases blocked both processes. p38 was also activated by cisplatin with similar kinetics as JNK. AP-1 complexes were activated by cisplatin including mainly c-jun/ATF-2 heterodimers suggesting that AP-1-dependent transcription partially mediated cisplatin-induced apoptosis.
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PMID:Lack of c-Jun activity increases survival to cisplatin. 1040 93

Ewing's sarcoma family of tumors (ESFTs) affects patients between the ages of 3 and 40 years, with most cases occurring in the second decade of life. These tumors contain a characteristic translocation, t(11;22), that produces a unique fusion protein, EWS/FLI-1. EWS/FLI-1 transforms mouse fibroblasts; this transformation requires intact EWS and FLI-1 domains as well as the insulin-like growth factor-I receptor (IGF-IR). The IGF-IR is a well-described transmembrane tyrosine kinase receptor that modulates transformation, cell growth, and survival. IGF-IR survival signaling is mediated through the downstream activation of phosphoinositide 3-OH kinase (PI 3-K) and Akt. Apoptosis, programmed cell death, progresses from a central death signal to a caspase cascade, including activation of caspase-3. Because the IGF-IR has been shown to play a role in the transformation and growth of ESFTs, we wanted to determine the role of downstream molecules in the cellular response to doxorubicin treatment. Doxorubicin increased caspase-3 activity in two ESFT cell lines, TC-32 and TC-71. Concomitant treatment of the doxorubicin-treated cells with IGF-I reduced caspase-3 activity 8-fold in TC-32 and 4-fold in TC-71. To determine whether PI 3-K has a role in IGF-I-mediated survival in ESFTs, PI 3-K was then inhibited with wortmannin and LY294002. Doxorubicin treatment reduced cell number and enhanced apoptosis in PI 3-K inhibited cells compared with noninhibited cells. Akt, a serine/threonine kinase activated downstream of PI 3-K, was investigated to determine whether its constitutive activation would render ESFT cells more resistant to doxorubicin. A constitutively activated Akt was stably transfected into ESFT and those cells with high levels of expression demonstrated increased resistance to doxorubicin-induced caspase-3 activation. These results indicate that ESFT cell lines use an IGF-IR initiated signaling pathway through PI 3-K and Akt for survival when treated with doxorubicin.
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PMID:Phosphoinositide 3-hydroxide kinase blockade enhances apoptosis in the Ewing's sarcoma family of tumors. 1058 94

The second most prevalent urological malignancy in middle aged and elderly men is bladder cancer, with 90% of the cases being transitional cell carcinomas. The success of current systemic and intravesical therapeutic agents, such as cisplatin, thiotepa, Adriamycin, mitomycin C, and bacillus Calmette-Guerin, is limited with recurrence rates reduced to 17-44%. In addition, most of these agents require instrumentation of the urinary tract and are delivered at a significant cost and potential morbidity to the patient. Fluroquinolone antibiotics such as ciprofloxacin, which can be administered p.o., may have a profound effect in bladder cancer management. This is primarily based on limited in vitro studies on tumor cells derived from transitional cell carcinoma of the bladder that revealed a dose- and time-dependent inhibition of cell growth by ciprofloxacin at concentrations that are easily attainable in the urine of patients. However, the mechanism(s) by which ciprofloxacin elicits its biological effects on bladder cancer cells is not well documented. Our experimental data confirm previous studies showing the in vitro cell growth inhibition of the transitional cell carcinoma of the bladder cell line HTB9 and further showed the induction of cell cycle arrest at the S/G2-M checkpoints. In addition, we found down-regulation of cyclin B, cyclin E, and dephosphorylation of cdk2 in ciprofloxacin-treated bladder tumor cells. There was also an up-regulation of Bax, which altered the Bax:Bcl-2 ratio, which may be responsible for mitochondrial depolarization reported to be involved prior to the induction of apoptosis. The cyclin-dependent kinase inhibitor p21WAF1 level was found to be decreased within 12 h of ciprofloxacin treatment and disappeared completely when HTB9 cells were treated with 200 microg/ml ciprofloxacin for 24 h. The down-regulation of p21WAF1 closely correlated with poly(ADP-ribose) polymerase cleavage and CPP32 activation. Recent studies revealed that p21WAF1 protects cells from apoptosis by arresting them in G1 and further binds to pro-caspase-3, preventing its activation and thus, inhibiting the apoptotic cascade. Hence, the down-regulation of p21WAF1, together with the alterations in Bax and cdk2 as observed in our studies, may define a novel mechanism by which ciprofloxacin inhibits tumor cell growth and induces apoptotic cell death. The results of our current studies provide strong experimental evidence for the use of ciprofloxacin as a potential preventive and/or therapeutic agent for the management of transitional cell carcinoma of the bladder.
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PMID:Ciprofloxacin mediated cell growth inhibition, S/G2-M cell cycle arrest, and apoptosis in a human transitional cell carcinoma of the bladder cell line. 1074 13

Anti-Fas monoclonal antibody (mAb) kills Fas-expressing cells by apoptosis. Several anticancer agents also mediate apoptosis and may share common intracellular pathways leading to apoptosis with Fas. Thus, we reasoned that combination treatment of drug-resistant cells with anti-Fas mAb and drugs might overcome their resistance. We investigated whether anticancer agents enhance Fas-mediated apoptosis and cytotoxicity against renal cell carcinoma (RCC) cells. Treatment of ACHN RCC cells with anti-Fas mAb in combination with 5-fluorouracil, vinblastine, IFN-alpha, or IFN-gamma did not overcome resistance to these agents. However, combination treatment with anti-Fas mAb and Adriamycin (ADR) resulted in a synergistic cytotoxic effect. Furthermore, synergy was also obtained even when the exposure time was shortened from 24 h to 8 or 2 h. Synergy was also achieved in four other RCC cell lines and five freshly derived human RCC cells. Treatment with anti-Fas mAb in combination with epirubicin or pirarubicin also resulted in a synergistic cytotoxic effect on ACHN cells. Similar results were achieved with a combination of humanized anti-Fas mAb and ADR. Incubation of ACHN cells with ADR augmented the expression of Fas and p53, but not Bcl-2, Bax, or caspase-3. However, the activity of caspase-3 itself was apparently enhanced after treatment with ADR alone or combined treatment with anti-Fas mAb. The synergy obtained in cytotoxicity with anti-Fas mAb and ADR was also achieved in apoptosis. Exposure of ACHN cells and freshly derived RCC cells to ADR enhanced their susceptibility to lysis by peripheral blood lymphocytes and tumor-infiltrating lymphocytes. This study demonstrates that combination treatment of RCC cells with anti-Fas mAb and ADR might overcome their resistance. The sensitization required a low concentration of ADR and a short exposure time, thus supporting the potential in vivo application of a combination of ADR and anti-Fas mAb or immunotherapy in the treatment of ADR- and/or immunotherapy-resistant RCC.
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PMID:Enhancement of Fas-mediated apoptosis in renal cell carcinoma cells by adriamycin. 1085 Apr 37

Doxorubicin (DOX) is a broad spectrum anthracycline antibiotic used to treat a variety of cancers. Redox activation of DOX to form reactive oxygen species has been implicated in DOX-induced cardiotoxicity. In this work we investigated DOX-induced apoptosis in cultured bovine aortic endothelial cells and cardiomyocytes isolated from adult rat heart. Exposure of bovine aortic endothelial cells or myocytes to submicromolar levels of DOX induced significant apoptosis as measured by DNA fragmentation and terminal deoxynucleotidyltransferase-mediated nick-end labeling assays. Pretreatment of cells with 100 microm nitrone spin traps, N-tert-butyl-alpha-phenylnitrone (PBN) or alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (POBN) dramatically inhibited DOX-induced apoptosis. Ebselen (20-50 microm), a glutathione peroxidase mimetic, also significantly inhibited apoptosis. DOX (0.5-1 microm) inactivated mitochondrial complex I by a superoxide-dependent mechanism. PBN (100 microm), POBN (100 microm), and ebselen (50 microm) restored complex I activity. These compounds also inhibited DOX-induced caspase-3 activation and cytochrome c release. PBN and ebselen also restored glutathione levels in DOX-treated cells. We conclude that nitrone spin traps and ebselen inhibit the DOX-induced apoptotic signaling mechanism and that this antiapoptotic mechanism may be linked in part to the inhibition in formation or scavenging of hydrogen peroxide. Therapeutic strategies to mitigate DOX cardiotoxicity should be reexamined in light of these emerging antiapoptotic mechanisms of antioxidants.
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PMID:Doxorubicin-induced apoptosis in endothelial cells and cardiomyocytes is ameliorated by nitrone spin traps and ebselen. Role of reactive oxygen and nitrogen species. 1089 61

Doxorubicin induces caspase-3 activation and apoptosis in Jurkat cells but inhibition of this enzyme did not prevent cell death, suggesting that another caspase(s) is critically implicated. Western blot analysis of cell extracts indicated that caspases 2, 3, 4, 6, 7, 8, 9, and 10 were activated by doxorubicin. Cotreatment of cells with the caspase inhibitors Ac-DEVD-CHO, Z-VDVAD-fmk, Z-IETD-fmk, and Z-LEHD-fmk alone or in combination, or overexpression of CrmA, prevented many morphological features of apoptosis but not loss of mitochondrial membrane potential (delta(psi)m), phospatidilserine exposure, and cell death. Western blot analysis of cells treated with doxorubicin in the presence of inhibitors allowed elucidation of the sequential order of caspase activation. Z-IETD-fmk or Z-LEHD-fmk, which inhibit caspase-9 activity, blocked the activation of all caspases studied, lamin B degradation, and the development of apoptotic morphology, but not cell death. All morphological and biochemical features of apoptosis, as well as cell death, were prevented by cotreatment of cells with the general caspase inhibitor Z-VAD-fmk or by overexpression of Bcl-2. Doxorubicin cytotoxicity was also blocked by the protein synthesis inhibitor cycloheximide. Delayed addition of Z-VAD-fmk after doxorubicin treatment, but prior to the appearance of cells displaying a low delta(psi)m, prevented cell death. These results, taken together, suggest that the key mediator of doxorubicin-induced apoptosis in Jurkat cells may be an inducible, Z-VAD-sensitive caspase (caspase-X), which would cause delta(psi)m loss, release of apoptogenic factors from mitochondria, and cell death.
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PMID:Doxorubicin treatment activates a Z-VAD-sensitive caspase, which causes deltapsim loss, caspase-9 activity, and apoptosis in Jurkat cells. 1091 4

Phosphorylated tau protein is the major component of paired helical filaments in Alzheimer disease (AD). We have previously shown that abnormal tau phosphorylation was induced in neuroblastoma SK-N-SH cells by the anticancer drug, paclitaxel, during apoptosis [Guise et al., 1999: Apoptosis 4:47-58]. In the present study, we first demonstrated a shift from fetal tau to hyperphosphorylated tau after incubation with paclitaxel, that showed some similarities with the hyperphosphorylated tau in AD, by using several tau antibodies, N-Term, Tau-1 and AT-8. Tau phosphorylation occurred independently of caspase-3 activation. We next showed that a sustained activation of ERK (extracellular signal-regulated kinase) induced both tau phosphorylation and apoptosis during paclitaxel treatment (1 microM). The inhibition of ERK activation by using the pharmacological MEK1/2 inhibitor, PD98059 (50 microM), or an antisense strategy, reduced tau phosphorylation and neuronal apoptosis (P < 0.001), indicating a link between ERK activation, tau phosphorylation and apoptosis. Doxorubicin (0.2 microM), an anticancer drug whose mechanism of action is independent of microtubules, also induced ERK activation, tau phosphorylation and apoptosis. Moreover, doxorubicin induced some morphological features of neurodegeneration such as loss of neurites and disorganization of the cytoskeleton in apoptotic neuroblastoma cells. Altogether, our results suggest that tau phosphorylation plays a significant role in apoptosis enhancing disruption of microtubules that in turn leads to formation of apoptotic bodies, suggesting that neurodegeneration and apoptosis are related.
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PMID:Hyperphosphorylation of tau is mediated by ERK activation during anticancer drug-induced apoptosis in neuroblastoma cells. 1117 Jan 75

There is growing evidence which suggests that dysregulation of apoptosis may lead to several disease states including cancer. To investigate the mechanism controlling the induction of cell death, apoptosis defective/resistant (Apt-) mutants were isolated and characterized in this study. FDC-P1, a mouse myeloid cell line that depends upon IL-3 for survival and growth but undergoes apoptosis when deprived of growth factor, was mutagenized by treatment with ethyl methane sulfonate. We selected cells that survived the growth factor deprivation but did not grow without the factor. Surviving cells were cloned by limiting dilution and four clones that showed the least morphological characteristics and biochemical changes of apoptosis were chosen. Unlike the parent FDC-P1, these mutants were cross resistant to apoptosis induced by a variety of antitumor drugs such as Adriamycin, Dexamethasone, VP-16, as well as reactive oxygen species (ROS) generated by xanthine/xanthine oxidase (X/XO). We used one of these Apt- mutant to test candidate death genes. Our findings suggest that the preferential increase in Bax/Bcl-2 ratio, p53, c-Myc, Caspase-3 and decrease in AP-1 on treatment with various anticancer drugs may contribute to the preferential apoptotic response in FDC-P1 cells but to varying degrees. Whereas, the higher constitutive level of antioxidant enzymes superoxide dismutase and catalase in the Apt- mutant may contribute at least in part to its resistance.
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PMID:Differential sensitivity of murine myeloid FDC-P1 cells and apoptosis resistant mutant(s) to anticancer drugs. 1123 67

The dose-dependent cardiomyopathy and heart failure due to adriamycin have been shown to be due to increased oxidative stress and loss of myocytes. We examined the incidence of myocardial apoptosis as well as changes in the expression of apoptotic regulatory gene products in an established animal model of adriamycin cardiomyopathy. Rats were treated with adriamycin (cumulative dose, 15 mg/kg), and the hearts were examined for apoptosis as well as expression of Bax, caspase 3, and Bcl-2 at 0, 4, 10, 16, and 21 days after the treatment. A significant increase in the incidence of apoptosis was seen at 4 days, followed by a decline at 10 and 16 days of posttreatment. At 21 days, the number of apoptotic cells increased again and included cells of the conducting system. Expression of Bax corresponded to these biphasic changes, whereas the converse was true for the expression of Bcl-2. The latter peaked at 10 days followed by a decline at 16 and 21 days. The Bax/Bcl-2 ratio also correlated with the incidence of apoptosis. Expression of caspase 3 correlated with increased apoptosis, but only at early time points. Probucol (cumulative dose, 120 mg/kg), a known antioxidant as well as promoter of endogenous antioxidants, significantly reduced the incidence of apoptosis as well as expression of Bax. Adriamycin-induced hemodynamic changes were also prevented by probucol. These data suggest that adriamycin-induced apoptosis is mediated by oxidative stress and may play a role in the development of heart failure.
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PMID:Apoptosis in adriamycin cardiomyopathy and its modulation by probucol. 1129 92


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