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)

We examined the effect of apogossypolone (ApoG2), a new derivative from gossypol on cell cycle regulation in U937 human leukemic monocyte lymphoma cells in vitro. ApoG2 decreased the viability of U937 cells by inducing G1 arrest followed by apoptosis in a dose-dependent manner. The G0/G1 phase of the cell cycle is regulated by cyclin-dependent kinases (Cdk), cyclins and cyclin-dependent kinase inhibitors (Cdki). We show by western blot analysis, that the ApoG2-induced G1 arrest was mediated through the increased expression of Cdki proteins (p21cip1/waf1) with a simultaneous decrease in cdk2, cdk4, cyclin D1 and cyclin E expression. The induction of apoptosis after treatment with ApoG2 for 12, 24 and 48 h was demonstrated by flow cytometry analysis. ApoG2 also induced cytochrome c release and activation of caspase-3. To our knowledge, this is the first time that ApoG2 has been reported to potently inhibit the proliferation of human monocytic lymphoma U937 cells through G1 arrest. These findings suggest that ApoG2 may be a potential chemotherapeutic agent for the treatment of cancer.
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PMID:Apogossypolone inhibits cell growth by inducing cell cycle arrest in U937 cells. 1951 23

Increased expression and activity of proteins driving cell cycle progression as well as inactivation of endogenous inhibitors of cyclin-dependent kinases (CDKs) enhance the proliferative potential of cells. Escape of cells during malignant transformation from the proper cell cycle control rendering them independent from growth factors provides rationale for therapeutic targeting of CDKs. Exposure of rapidly growing human MCF-7 breast cancer and HeLa cervix cancer cells to roscovitine (ROSC), a selective inhibitor of CDKs, inhibits their proliferation by induction of cell cycle arrest and/or apoptosis. The outcome strongly depends on the intrinsic traits of the tumor cells, on their cell cycle status prior to the onset of treatment and also on ROSC concentration. At lower dose ROSC primarily inhibits the cell cycle-related CDKs resulting in a strong cell cycle arrest. Interestingly, ROSC arrests asynchronously growing cells at the G(2)/M transition irrespective of the status of their restriction checkpoint. However, the exposure of cancer cells synchronized after serum starvation in the late G(1) phase results in a transient G(1) arrest only in cells displaying the intact G(1)/S checkpoint. At higher dosage ROSC triggers apoptosis. In HeLa cells inhibition of the activity of CDK7 and, in consequence, that of RNA polymerase II is a major event that facilitates the initiation of caspase-dependent apoptosis. In contrast, in the caspase-3-deficient MCF-7 breast cancer cells ROSC induces apoptosis by a p53-dependent pathway. HIPK2-mediated activation of the p53 transcription factor by phosphorylation at Ser46 results in upregulation of p53AIP1 protein. This protein after de novo synthesis and translocation into the mitochondria promotes depolarization of the mitochondrial membrane.
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PMID:Impact of roscovitine, a selective CDK inhibitor, on cancer cells: bi-functionality increases its therapeutic potential. 1972 78

Naphtho[1,2-b]furan-4,5-dione (NFD), prepared from 2-hydroxy-1,4-naphthoquinone and chloroacetaldehyde in an efficient one-pot reaction, exhibits anti-carcinogenic effect. The results of present study showed that NFD inhibited the proliferation of breast cancer MDA-MB-231 cells through the induction of S-phase arrest and apoptosis. NFD-induced S-phase arrest was associated with a marked decrease in the protein expression of cyclin A, cyclin B, and cyclin-dependent kinase (Cdk)2. NFD-induced apoptosis was characterized by increase of sub-G1 population, phosphatidylserine (PS) externalization, and activation of caspases. Moreover, up-regulation of Bad and down-regulation of Bcl-2, Bcl-X(L), and survivin led to the loss of mitochondrial membrane potential (DeltaPsim), the release of cytochrome c and sequential activation of caspase-9 and caspase-3. NFD activated c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-regulated kinase (ERK) in MDA-MB-231 cells. Inhibitors of JNK (SP600125) and ERK (PD98059), but not p38 MAPK (SB203580) suppressed NFD-induced S-phase arrest and apoptosis in MDA-MB-231 cells. Both SP600125 and PD98059 attenuated Bad up-regulation, and reversed down-regulation of Bcl-2, Bcl-X(L), survivin, cyclin A, cyclin B, and Cdk2 in NFD-treated cells. Taken together, our data show that JNK and ERK-signaling pathways play important roles in NFD-mediated S-phase arrest and apoptosis of MDA-MB-231 cells.
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PMID:Naphtho[1,2-b]furan-4,5-dione induces apoptosis and S-phase arrest of MDA-MB-231 cells through JNK and ERK signaling activation. 1974 39

The cycle inhibiting factor (Cif) belongs to a family of bacterial toxins, the cyclomodulins, which modulate the host cell cycle. Upon injection into the host cell by the type III secretion system of enteropathogenic Escherichia coli (EPEC), Cif induces both G(2) and G(1) cell cycle arrests. The cell cycle arrests correlate with the accumulation of p21(waf1) and p27(kip1) proteins that inhibit CDK-cyclin complexes, whose activation is required for G(1)/S and G(2)/M transitions. Increases of p21 and p27 levels are independent of p53 transcriptional induction and result from protein stabilization through inhibition of the ubiquitin/proteasome degradation pathway. In this study, we show that Cif not only induces cell cycle arrest but also eventually provokes a delayed cell death. Indeed, 48 h after infection with EPEC expressing Cif, cultured IEC-6 intestinal cells were positive for extracellular binding of annexin V and exhibited high levels of cleaved caspase-3 and lactate dehydrogenase release, indicating evidence of apoptosis. Cif was necessary and sufficient for inducing this late apoptosis, and the cysteine residue of the catalytic site was required for Cif activity. These results highlight a more complex role of Cif than previously thought, as a cyclomodulin but also as an apoptosis inducer.
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PMID:The enteropathogenic Escherichia coli effector Cif induces delayed apoptosis in epithelial cells. 1978 59

Glioma still remains a major health problem in the world. Celastrol has been proved to be an effective natural proteasome inhibitor and was used for treatment of autoimmune disease, chronic inflammation and neurodegenerative disease. However, its effect on glioma is unclear. In this study, we investigated the therapeutic effects of celastrol on C6 glioma cells. The results demonstrated that celastrol inhibited cell proliferation in a time- and dose-dependent manner, suppressed proteasome chymotrypsin-like activity and induced apoptosis and cell cycle arrest at G2/M phase in C6 cells. Proapoptosis proteins bax and caspase-3 were up-regulated, as well as cell cycle G2/M-related proteins cyclin B(1), p21 and p27. Conversely, anti-apoptosis proteins bcl-2 and XIAP and cell cycle regulator cyclin-dependent kinase 2 were down-regulated. Taken together, our data suggest that celastrol can suppress proteasome activity and induce apoptosis and cell cycle arrest in C6 glioma cells, which make it be a potential drug for glioma.
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PMID:Celastrol causes apoptosis and cell cycle arrest in rat glioma cells. 1990 82

Roscovitine, a cyclin-dependent kinases (CDKs) inhibitor, has been reported to have anti-tumor effects in some cancer cell lines by inducing apoptosis. However, the exact underlying mechanisms are not fully understood. Here, we report that roscovitine induces expression and cleavage of the universal CDK inhibitor p21Waf1/Cip1 in non-small cell lung cancer (NSCLC) A549 cells in a dose-dependent manner. Western blots of roscovitine-treated cells undergoing apoptosis consistently demonstrated a 15 kDa band that was not detected in control cultures. CDK2 activity and PCNA expression were repressed with increasing dose of roscovitine. Accompanying these molecular changes was a progressive arrest of G2 phase and decreasing of 5-bromo-2-deoxyuridine (Brdu) incorporation of S phase cells. Caspase-3 inhibitor z-DEVD-fmk almost completely abolished roscovitine-induced apoptosis, as well as the appearance of 15 kDa band, indicating that p21Waf1/Cip1 cleavage was mediated by caspase-3 activity. Furthermore, this band was predominant in the floating apoptotic cells, while weakened in the adherent cells which were vital and pre-apoptotic. We also showed that roscovitine induced an enhanced expression of gamma-H2AX, which was blocked by caspase-3 inhibition, suggesting that p21Waf1/Cip1 cleavage may interfere with DNA repair, leading to increased frequency of double strand breaks (DSBs) and enhanced apoptosis. Here we show, for the first time, that p21Waf1/Cip1 cleavage, which is mediated by caspase-3 activity, is involved in roscovitine-induced apoptosis.
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PMID:Involvement of p21Waf1/Cip1 cleavage during roscovitine-induced apoptosis in non-small cell lung cancer cells. 1995 88

Ginsenoside Rg3 has been a subject of interest for use as a cancer preventive or therapeutic agent. Nuclear factor-kappa (NF-kappaB) is constitutively activated in prostate cancer, and gives cancer cells resistance to chemotherapeutic agents. To investigate whether Rg3 can suppress the activation of NF-kappaB, and thus increase susceptibility of prostate (LNCaP and PC-3, DU145) cells against chemotherapeutics, prostate cancer cell growth as well as activation of NF-kappaB was examined. We found that a combination treatment of Rg3 (50 microM) with a conventional agent docetaxel (5 nM) was more effective in the inhibition of prostate cancer cell growth and induction of apoptosis as well as G(0)/G(1) arrest accompanied with the significant inhibition of NF-kappaB activity than those by treatment of Rg3 or docetaxel alone. It was also found that NF-kappaB target gene expression of Bax, caspase-3, and caspase-9 was much more significantly enhanced, but the expression of Bcl-2, inhibitor of apoptosis protein (IAP-1) and X chromosome IAP (XIAP), and the expression of cell cycle regulatory proteins cyclin B, D1 and E, and cyclin dependent kinases 2 and 4 was also much more significantly inhibited by the combination treatment. The combination of Rg3 (50 microM) with cisplatin (10 microM) and doxorubicin (2 microM) was also more effective in the inhibition of prostate cancer cell growth and NF-kappaB activity than those by the treatment of Rg3 or chemotherapeutics alone. These results indicate that ginsenoside Rg3 inhibits NF-kappaB, and enhances the susceptibility of prostate cancer cells to docetaxel and other chemotherapeutics. Thus, ginsenoside Rg3 could be useful as an anti-cancer agent.
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PMID:Combination of ginsenoside Rg3 with docetaxel enhances the susceptibility of prostate cancer cells via inhibition of NF-kappaB. 2005 15

Nitric oxide (NO), a multifaceted signaling molecule, regulates a wide array of cell functions, including proliferation, differentiation, cytostasis, and apoptosis, which depend on the cell type and redox status. This study systematically explores the effects of NO donors on promyelocytic HL-60 cell proliferation and apoptosis. The NO donor DETA-NO modulated the HL-60 cell cycle in a biphasic manner. DETA-NO in lower concentrations (1-100 microM) had a proliferative effect as investigated by [(3)H]thymidine incorporation, BrdU labeling, and cell cycle analysis, whereas cells treated with higher concentrations (250 microM-1 mM) showed cytostasis, apoptosis, mitochondrial membrane potential loss, caspase-3 activity, and dUTP nick-end labeling. The proliferative effect of DETA-NO was NO dependent and redox sensitive, as the effect was abolished by cPTIO and DTT pretreatment, respectively. Expression of various cell cycle regulators such as Cdk2, cyclin B, and cyclin E was significantly augmented in cells treated with 10-50 microM DETA-NO. The proliferative effect of NO was blocked by roscovitine, a Cdk2 inhibitor. S-nitrosylation of Cdk2 and an increase in the Cdk2-associated kinase activity was observed for the first time in DETA-NO-treated cells. This study demonstrates that the DETA-NO-mediated biphasic effect was dependent on Cdk2 nitrosylation/activation and the loss of mitochondrial potential at low and high concentrations, respectively.
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PMID:Cdk2 nitrosylation and loss of mitochondrial potential mediate NO-dependent biphasic effect on HL-60 cell cycle. 2007 29

Deregulation of cell-cycle control is a hallmark of cancer. Thus, cyclin-dependent kinases (Cdks) are an attractive target for the development of anti-cancer drugs. Here, we report the biological characterization of a highly potent pan-Cdk inhibitor with a macrocycle-quinoxalinone structure. Compound M inhibited Cdk1, 2, 4, 5, 6, and 9 with equal potency in the nM range and was selective against kinases other than Cdks. This compound inhibited multiple events in the cell cycle in vitro, including retinoblastoma protein (pRb) phosphorylation, E2F-dependent transcription, DNA replication (determined by bromodeoxyuridine incorporation), and mitosis completion (assayed by flow cytometry) in the 10 nM range. Moreover, this compound induced cell death, as determined by induction of the subG1 fraction, activated caspase-3, and anexin V. In vivo, Compound M showed anti-tumor efficacy at a tolerated dose. In a nude rat xenograft tumor model, an 8-h constant infusion of Compound M inhibited pRb phosphorylation and induced apoptosis in tumor cells at ~ 30 nM, which led to the inhibition of tumor growth. Immunosuppression was the only liability observed at this dose, but immune function returned to normal after 10 days. Suppression of pRb phosphorylation in tumor cells was clearly correlated with tumor cell growth inhibition and cell death in vitro and in vivo. In vivo, Compound M inhibited pRb phosphorylation in both tumor and gut crypt cells. Rb phosphorylation may be a suitable pharmacodynamic biomarker in both tumors and normal tissues for monitoring target engagement and predicting the efficacy of Compound M.
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PMID:Potent anti-tumor activity of a macrocycle-quinoxalinone class pan-Cdk inhibitor in vitro and in vivo. 2008 24

The antiproliferative and apoptotic effects of cucurbitacin E, a natural product isolated from Cucurbitaceae, were determined in human leukemia HL-60 cells. Cucurbitacin E at low concentrations (3-50 nmol/l) inhibited the growth of HL-60 cells, which was associated with G2/M cell-cycle arrest, decrease in the levels of cyclin-dependent kinase1, and increase in the levels of p21. Cucurbitacin E at high concentrations (1-10 mol/l) induced apoptosis of HL-60 cells and activation of caspase-3, caspase-8, and caspase-9. Jurkat leukemia cells with or without caspase-8 expression were nearly equally sensitive to cucurbitacin E-induced apoptosis. Cucurbitacin E did not increase the levels of reactive oxygen species and antioxidants, N-acetylcysteine and catalase, did not block cucurbitacin E-induced apoptosis. Cucurbitacin E decreased the levels of the antiapoptotic proteins XIAP, survivin, and Mcl-1, but increased the level of the proapoptotic protein, Bax. The levels of phosphorylated eukaryotic translation initiation factor 2 subunit (eIF2) were induced in cells undergoing both apoptosis and cell-cycle arrest. As phosphorylated eIF2 is an inhibitor of protein translation initiation, our data suggest that cucurbitacin E induces cell growth arrest and apoptosis through the induction of eIF2 phosphorylation, which leads to the inhibition of cyclin-dependent kinase 1, Mcl-1, survivin, and/or XIAP protein synthesis and that cucurbitacin E induces apoptosis mainly through a mitochondrial-mediated pathway.
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PMID:The induction of G2/M cell-cycle arrest and apoptosis by cucurbitacin E is associated with increased phosphorylation of eIF2alpha in leukemia cells. 2011 Aug 7


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