Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.22.56 (caspase-3)
 35,750 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study, we have synthesized several compounds and examined their cytotoxic effects on human non-small cell lung cancer A549 cells. We found that GO-13 ((E,E)-2,5-bis[4-(3-dimethyl-aminopropoxy)styryl]-1,3,4-thiadiazole) is the most effective one by the MTT assay. Furthermore, the GO-13-induced apoptotic reaction was identified based on several criteria, such as negative release reaction of lactate dehydrogenase and positive labeling of annexin V and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) techniques. GO-13 induced the apoptosis in A549 cells in a concentration- and time-dependent manner. The data demonstrate that the regulations of p38 mitogen-activated protein kinase and protein kinase C was not involved in the GO-13-mediated mechanism. However, GO-13 significantly induced a down-regulation of Bcl-X(L) expression in a short-term treatment (less than 3hr), whereas stimulated up-regulation of Bax expression in a long-term treatment (24hr) indicating their involvement in GO-13 action. GO-13-mediated apoptosis is also positively correlated with the increase in caspase-3 activity. Worth noting is the fact that GO-13 did not modify the phosphorylation level of Akt/protein kinase B (PKB) until a 24-hr exposure was carried out indicating that the inhibition of Akt/PKB activation was involved in the late-phase apoptosis. Besides the anticancer activity, GO-13 also showed equivalent anti-angiogenic activity in the nude mice angiogenesis model. In summary, we conclude that GO-13 is the most effective anticancer compound in our screening tests. It induced the early-phase apoptosis in A549 cells via the Bcl-X(L) down-regulation, and that of the late-phase through up-regulation of Bax expression as well as inhibition of Akt/PKB activation.
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PMID:Investigation of anticancer mechanism of thiadiazole-based compound in human non-small cell lung cancer A549 cells. 1281 71

Fibroblast growth factor-2 (FGF-2) is involved as an autocrine growth factor in the autonomous proliferation of glioma cells. To develop a new strategy for treating patients with glioma, we studied the effect on human glioma cells of a 16-mer oligopeptide with conformational similarity to the putative receptor-binding domain of FGF-2. A synthesized oligonucleotide was assessed its receptor-binding activity by BIAcore instrument. Its biological effect on glioma cell lines was examined in vitro by MTT assay. The peptide suppressed the in vitro growth of human glioma cells U87MG, T98G and U251MG cells, but not of A431 cells whose growth is not dependent on FGF-2. Apoptotic bodies were noted after 24-h incubation in the presence of the peptide; Ac-YVAD-CHO, a caspase-3 inhibitor, suppressed apoptosis. Furthermore, we examined the modulation of the cytotoxic effect of anticancer drugs by the oligopeptide. The addition of this oligopeptide to the chemotherapeutic agents CDDP, ACNU and VP16 had additive effects in vitro. These results suggest that the pathway of the FGF-2 autocrine loop through the FGF receptor plays an important role in the proliferation of glioma cells. New drugs targeting this loop may be highly effective in treating FGF-2-dependent tumors. Our results suggest that its addition to the therapeutic arsenal may lead to improved treatment regimens for patients with FGF-2-dependent tumors.
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PMID:In vitro growth suppression of human glioma cells by a 16-mer oligopeptide: a potential new treatment modality for malignant glioma. 1282 20

The mechanism by which beta-amyloid protein (A beta) causes degeneration in cultured neurons is not completely understood, but several lines of evidence suggest that A beta-mediated neuronal death is associated with an enhanced production of reactive oxygen species (ROS) and oxidative damage. In the present study, we address whether supplementation of glucose-containing culture media with energy substrates, pyruvate plus malate (P/M), protects rat primary neurons from A beta-induced degeneration and death. We found that P/M addition attenuated cell death evoked by beta-amyloid peptides (A beta(25-35) and A beta(1-40)) after 24 hr treatment and that this effect was blocked by alpha-ciano-3-hydroxycinnamate (CIN), suggesting that it requires mitochondrial pyruvate uptake. P/M supply to control and A beta-treated neuronal cultures increases cellular reducing power, as indicated by the ability to reduce the dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The early increases in ROS levels, measured by dichlorofluorescein (DCF) fluorescence, and caspase-3 activity that follow exposure to A beta were notably reduced in the presence of P/M. These results place activation of caspase-3 most likely downstream of oxidative damage to the mitochondria and indicate that mitochondrial NAD(P) redox status plays a central role in the neuroprotective effect of pyruvate. Inhibition of respiratory chain complexes and mitochondrial uncoupling did not block the early increase in ROS levels, suggesting that A beta could initiate oxidative stress by activating a source of ROS that is not accesible to the antioxidant defenses fueled by mitochondrial substrates.
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PMID:Pyruvate protection against beta-amyloid-induced neuronal death: role of mitochondrial redox state. 1283 69

The purpose of this study was to investigate the potential neuroprotective effects of myricetin (flavonoid) and fraxetin (coumarin) on rotenone-induced apoptosis in SH-SY5Y cells, and the possible signal pathway involved in a neuronal cell model of Parkinson's disease. These two compounds were compared to N-acetylcysteine. The viability of cells was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and cytotoxicity was assayed by lactate dehydrogenase (LDH) released into the culture medium. Parameters related to apoptosis, such as caspase-3 activity, the cleavage of poly(ADP-ribose) polymerase and the levels of reactive oxygen species were also determined. Rotenone caused a time- and dose-dependent decrease in cell viability and the degree of LDH release was proportionally to the effects on cell viability. Cells were pretreated with fraxetin, myricetin and N-acetylcysteine at different concentrations for 30 min before exposure to rotenone. Cytotoxicity of rotenone (5 microM) for 16 h was significantly diminished as well as the release of LDH into the medium, by the effect of fraxetin, myricetin and N-acetylcysteine, with fraxetin (100 microM) and N-acetylcysteine (100 microM) being more effective than myricetin (50 microM). Rotenone-induced apoptosis in SH-SY5Y cells was detected by an increase in caspase-3 activity and in the cleavage of poly(ADP-ribose) polymerase. After exposing these cells to rotenone, a significant increase in reactive oxygen species preceded apoptotic events. Fraxetin (100 microM) and N-acetylcysteine (100 microM) not only reduced rotenone-induced reactive oxygen species formation, but also attenuated caspase-3 activity and poly(ADP-ribose) polymerase cleavage at 16 h against rotenone-induced apoptosis. The effect of fraxetin in both experiments was similar to that of N-acetylcysteine. These results demonstrated the protective action of fraxetin and suggest that it can reduce apoptosis, possibly by decreasing free radical generation in SH-SY5Y cells. Myricetin at 100 microM was without any preventive effect.
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PMID:Effect of fraxetin and myricetin on rotenone-induced cytotoxicity in SH-SY5Y cells: comparison with N-acetylcysteine. 1286 Apr 76

Flavonoids were demonstrated to possess several biological effects including antitumor, antioxidant, and anti-inflammatory activities in our previous studies. However, the effect of glycosylation on their biological functions is still undefined. In the present study, the apoptosis-inducing activities of three structure-related flavonoids including aglycone quercetin (QUE), and glycone rutin (RUT; QUE-3-O-rutinoside), and glycone quercitrin (QUI; QUE-3-O-rhamnoside) were studied. Both RUT and QUI are QUE glycosides, and possess rutinose and rhamnose at the C3 position of QUE, respectively. Results of the MTT assay showed that QUE, but not RUT and QUI, exhibits significant cytotoxic effect on HL-60 cells, accompanied by the dose- and time-dependent appearance of characteristics of apoptosis including an increase in DNA ladder intensity, morphological changes, apoptotic bodies, and an increase in hypodiploid cells by flow cytometry analysis. QUE, but not RUT or QUI, caused rapid and transient induction of caspase 3/CPP32 activity, but not caspase 1 activity, according to cleavage of caspase 3 substrates poly(ADP-ribose) polymerase (PARP) and D4-GDI proteins, and the appearance of cleaved caspase 3 fragments being detected in QUE- but not RUT- or QUI-treated HL-60 cells. A decrease in the anti-apoptotic protein, Mcl-1, was detected in QUE-treated HL-60 cells, whereas other Bcl-2 family proteins including Bax, Bcl-2, Bcl-XL, and Bag remained unchanged. The caspase 3 inhibitor, Ac-DEVD-FMK, but not the caspase 1 inhibitor, Ac-YVAD-FMK, attenuated QUE-induced cell death. Results of DCHF-DA assay indicate that no significant increase in intracellular peroxide level was found in QUE-treated cells, and QUE inhibited the H(2)O(2)-induced intracellular peroxide level. Free radical scavengers N-acetyl-cysteine (NAC) and catalase showed no prevention of QUE-induced apoptosis. In addition, QUE did not induce apoptosis in an mature monocytic cell line THP-1, as characterized by a lack of DNA ladders, caspase 3 activation, PARP cleavage, and an Mcl-1 decrease, compared with those in HL-60 cells. Our experiments provide evidence to indicate that the addition of rutinose or rhamnose attenuates the apoptosis-inducing activity of QUE, and that the caspase 3 cascade but not free radical production is involved.
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PMID:Differential apoptosis-inducing effect of quercetin and its glycosides in human promyeloleukemic HL-60 cells by alternative activation of the caspase 3 cascade. 1287 37

In the context of atherogenesis and restenosis, vascular smooth muscle cell (SMC) proliferation and apoptosis play a crucial role. Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (statins) have been shown to inhibit the migration and proliferation of SMC, and to induce apoptosis in different cell types including SMC. However, it is not known whether these agents induce apoptosis in neointimal SMC. We investigated the effects of statin treatment on neointimal SMC as compared to medial cells by using trypan blue counting, MTT test, Annexin V staining, cell cycle analysis and a co-culture model. The incubation of neointimal or medial SMC with lovastatin reduced the MTT activity as well as the total cell number, and increased the amount of trypan blue positive cells, indicative of cell death. We tested by staining with Annexin V/propidium iodide, specific antibodies to active caspase-3, TUNEL reaction, and by the appearance of a sub-G1 peak, whether the observed increase in cell death was due to apoptosis. After treatment with lovastatin, programmed cell death was slightly increased in medial SMC, while neointimal cells showed a pronounced rate of apoptosis. In an attempt to mimic early phases of restenosis in vitro by seeding low density neointimal cells onto high density medial cells, we found that statin treatment induced cell death preferentially in the neointimal SMC. Our results suggest that statins enhance the rate of apoptosis in neointimal SMC, which may be an interesting feature to reduce restenosis after successful angioplasty.
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PMID:HMG-CoA reductase inhibitors induce apoptosis in neointima-derived vascular smooth muscle cells. 1292 76

The protective effect of Acanthopanax senticosus (AS) against ethanol (EtOH)-induced apoptosis of the human neuroblastoma cell line SK-N-MC was investigated via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometric analysis, DNA fragmentation assay, reverse transcription-polymerase chain reaction (RT-PCR), and caspase-3 assay. It was shown that cells treated with EtOH exhibit classical apoptotic features, while cells pre-treated with Acanthopanax senticosus prior to EtOH exposure showed decreased occurrence of apoptotic features. In addition, Acanthopanax senticosus pre-treatment was shown to inhibit EtOH-induced increase in caspase-3 mRNA expression and activity. These results suggest that Acanthopanax senticosus may exert a protective effect against EtOH-induced apoptosis of human neuroblastoma cells.
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PMID:Protective effect of Acanthopanax senticosus against ethanol-induced apoptosis of human neuroblastoma cell line SK-N-MC. 1294 69

To investigate the inhibiting effect of arsenic trioxide (As(2)O(3)) on the telomerase activity of leukemia cell lines NB4 and Jurkat cells, MTT assay, electrophoresis of genomic DNA, protein/DNA dual parameter flow cytometry as well as a semi-quantitative telomeric repeat amplification protocol (TRAP) assay and RT-PCR were used to examine the effect of As(2)O(3) on cell proliferation, telomerase activity and expression of cell cycle regulatory proteins. The results showed that cell proliferation and telomerase activity were significantly inhibited and apoptosis was induced in these cells after exposure to As(2)O(3). Furthermore, the expression of some cell cycle and apoptosis related proteins, such as Bcl-2, Rb, P16, caspase-3, cyclin A and cyclin E, was altered in As(2)O(3) treated NB4 cells. Cell cycle was arrested at G(1) and G(2)/M phases in both cells. It is concluded that the change of cell cycle regulatory proteins plays an important role in decline of the telomerase activity during the proliferation inhibition and apoptosis of NB4 and Jurkat cells induced by As(2)O(3).
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PMID:[Inhibiting effect of arsenic trioxide on telomerase activity of NB4 and Jurkat cell lines]. 1296 62

Rutinoside (rhamnoglucoside; rhamnose+glucose) addition has been examined extensively in the metabolism of flavonoids, however the effect of rutinoside on apoptosis-inducing activity of flavonoids is still unknown. In the present study, the two pairs of flavonoids of hesperetin (HT) and hesperidin (HD; HT-7-rutinose), and naringenin (NE) and naringin (NE-7-rutinose), were used to study their apoptosis-inducing activities in HL-60 cells. Both HD and NI are flavonoids which contain a rutinoside at the C7 of HT and NE, respectively. Results of the MTT assay showed that HT and NE, but not HD and NI, exhibited significant cytotoxic effect in HL-60 cells, accompanied by the dose- and time-dependent appearance of characteristics of apoptosis including an increase in DNA ladder intensity, morphological changes, appearance of apoptotic bodies, and an increase in hypodiploid cells by flow cytometry analysis. HT and NE, but not HD and NI, caused rapid and transient induction of caspase-3/CPP32 activity, but not caspase-1 activity, according to the cleavage of caspase-3 substrates poly(ADP-ribose) polymerase and D4-GDI proteins, the appearance of cleaved caspase-3 fragments detected in HT- or NE-, but not in HD- or NI-treated HL-60 cells. A decrease in the anti-apoptotic protein, Mcl-1, was detected in HT- and NE-treated HL-60 cells, whereas other Bcl-2 family proteins including Bax, Bcl-2, Bcl-XL, and Bag remained unchanged. The caspase-3 inhibitor, Ac-DEVD-FMK, but not the caspase-1 inhibitor, Ac-YVAD-FMK, attenuated HT- and NE-induced cell death. Interestingly, neither HT nor NE induced apoptosis in the mature monocytic cell line THP-1 and primary human polymorphonuclear cells, as characterized by a lack of DNA ladders, caspase-3 activation, poly(ADP-ribose) polymerase cleavage, and Mcl-1 decrease, compared with those in HL-60 cells. In addition, the rutinoside group in HD and NI was removed by hesperidinase and naringinase, accompanied by the production of HT and NE, respectively, according to HPLC analysis. Accordingly, hesperidinase and naringinase digestion recovered the apoptosis-inducing activity of HD and NI in HL-60 cells. Our experiments provide the first evidence to suggest that rutinoside in flavonoids prevents the induction of apoptosis, and that activation of the traditional caspase-3 cascade participates in HT- and NE-induced apoptosis.
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PMID:Rutinoside at C7 attenuates the apoptosis-inducing activity of flavonoids. 1450 93

DNA-dependent protein kinase (DNA-PK) is involved in non-homologous end joining which repairs DNA double-strand breaks introduced by irradiation and radiomimetic agents. DNA-PK interacts with p53 but may also have p53-independent functions. The present study investigated whether disruption of the gene for the catalytic subunit DNA-PKcs affects chemosensitivity in p53-deficient cells. Drug sensitivity of DNA-PKcs(+/+)/p53(+/+), DNA-PKcs(+/+)/p53(-/-), DNA-PKcs(-/-)/p53(+/+), and DNA-PKcs(-/-)/p53(-/-) mouse lung-fibroblasts was determined by the MTT assay, the clonogenic assay, and trypan blue exclusion. Susceptibility to apoptosis was determined by DNA fragmentation (TUNEL) and by caspase-3 cleavage. We show that p53-deficient cells were 2 to 3-fold resistant to treatment with doxorubicin, epirubicin, cisplatin, and docetaxel as compared to wild-type cells. We further demonstrate that the additional loss of DNA-PKcs function in p53-deficient cells resulted in a 2-fold increase in sensitivity to doxorubicin and epirubicin as documented by the MTT assay, clonogenic assay, and trypan blue exclusion. Doxorubicin-induced hypersensitivity in these cells correlated with a transient G2/M checkpoint activation but did not seem to correlate with apoptosis. The data indicate that additional loss of DNA-PKcs in p53-deficient cells reverses anthracycline-resistance imposed by p53-deficiency, and that DNA-PKcs modulates p53-independent pathways responding to DNA damage induced by anthracyclines. They also indicate that processes other than apoptosis may contribute to the increased cytotoxicity to anthracyclines. DNA-PKcs may thus be a potential target for functional inhibition, which might increase the efficacy of some anti-tumour agents in the treatment of cancers mutated in the p53 gene.
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PMID:p53-deficient cells display increased sensitivity to anthracyclines after loss of the catalytic subunit of the DNA-dependent protein kinase. 1453 87


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