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)

The molecular events involved in tumor cell death induced by novel photoproducts of merocyanine 540 (pMC540) are poorly understood. Using HL60 leukemia and M14 melanoma cell lines we investigated the role of the apoptotic pathway in pMC540-mediated cell death. Tumor cells exposed to pMC540 showed cell size shrinkage and an increase in the sub-diploid DNA content. A loss of membrane phospholipid asymmetry associated with apoptosis was induced by pMC540 in both tumor cell lines as evidenced by the externalization of phosphatidylserine. A dose-dependent increase in caspase-3 protease activity suppressed by the tetrapeptide inhibitor DEVD-CHO was observed in both cell lines. Western blot analysis of poly (ADP-ribose) polymerase, a caspase substrate, showed the classical cleavage pattern (116 to 89 kDa) associated with apoptosis in pMC540-treated cell lysates. Furthermore, caspase inhibition blocked the externalization of membrane PS, indicating that the loss of membrane phospholipid asymmetry is a downstream event of caspase activation. These findings demonstrate that tumor cell death induced by pMC540 is mediated by caspase proteases.
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PMID:Caspase proteases mediate apoptosis induced by anticancer agent preactivated MC540 in human tumor cell lines. 965 88

Our aim in this work was to define the role of c-Myc in the susceptibility to cisplatin [cis-diamminedichloroplatinum(II) (CDDP)] in human melanoma cells. Two M14 melanoma cell clones obtained by transfection and expressing six to ten times lower c-Myc protein levels than the parental cells and the control clone were employed. Analysis of survival curves demonstrates an increase in CDDP sensitivity in c-Myc low-expressing clones if compared with the control clone and the parental line. The enhanced sensitivity is unrelated to the impairment in enzymatic DNA repair activity. Cell cycle analysis demonstrates that although the control clone is able to completely recover from the CDDP-induced S-G(2)/M block, this arrest is prolonged in c-Myc low-expressing clones and a fraction of cells undergoes apoptosis. Although no changes in P53, Bax, Bcl-2, and Bcl-x(L/S) protein levels are observed, apoptosis is associated with the formation of reactive oxygen species (ROS), activation of caspase-1, caspase-3 and cleavage of the specific caspase substrate poly-ADP-ribose polymerase. The use of the antioxidant N-acetyl cysteine and caspase inhibitors prevents CDDP-induced apoptosis in c-Myc low-expressing clones, demonstrating that ROS, caspase-1, and caspase-3 are required for apoptotic cell death. Moreover, ROS generation depends on caspase-1-like activation because the Ac-YVAD-cho inhibitor abrogates CDDP-induced ROS in the c-Myc low-expressing clones.
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PMID:c-Myc down-regulation increases susceptibility to cisplatin through reactive oxygen species-mediated apoptosis in M14 human melanoma cells. 1140 12

Survivin is a structurally unique member of the inhibitors of apoptosis protein family and is involved in the control of cell division and inhibition of apoptosis. The notion that survivin is overexpressed in most human tumors but absent in normal adult tissues with only a few exceptions has led to the proposal of survivin as a promising therapeutic target for novel anticancer therapies. In this context, we generated a hammerhead ribozyme targeting the 3' end of the CUA110 triplet in the survivin mRNA. Two human melanoma cell lines (JR8 and M14) overexpressing survivin were stably transfected with the pRc/CMV vector carrying the ribozyme sequence. Two polyclonal cell populations proven to endogenously express ribozyme and characterized by a markedly lower survivin protein level (-60% and -50%, respectively) than JR8 and M14 parental cells were selected for the study. Ribozyme-expressing cells showed a significantly (p<0.01) increased sensitivity to gamma-irradiation (as detected by clonogenic cell survival) compared to JR8 and M14 cells. Moreover, in the JR8 cell line, the extent of radiation-induced apoptosis (in terms of percentage of apoptotic nuclei in cells stained with propidium iodide and level of caspase-3 catalytic activity) was markedly greater in ribozyme-expressing cells than in parental cells. These results demonstrate for the first time that attenuation of survivin expression renders human melanoma cells more susceptible to gamma-irradiation.
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PMID:Radiosensitization of human melanoma cells by ribozyme-mediated inhibition of survivin expression. 1264 30

Previous studies showed that long-wave ultraviolet (UVA) radiation induces severe skin damage through the generation of reactive oxygen species and the depletion of endogenous antioxidant systems. Recent results from our laboratory indicate a dramatic increase of both lipid peroxidation products (TBARS) and abnormal L-isoaspartyl residues, marker of protein damage, in UVA-irradiated human melanoma cells. In this study, the effects of hydroxytyrosol (DOPET), the major antioxidant compound present in olive oil, on UVA-induced cell damages, have been investigated, using a human melanoma cell line (M14) as a model system. In UVA-irradiated M14 cells, a protective effect of DOPET in preventing the uprise of typical markers of oxidative stress, such as TBARS and 2'7'-dichlorofluorescein (DCF) fluorescence intensity, was observed. In addition, DOPET prevents the increase of altered L-isoAsp residues induced by UVA irradiation. These protective effects are dose dependent, reaching the maximum at 400 microM DOPET. At higher concentrations, DOPET causes an arrest of M14 cell proliferation and acts as a proapoptotic stimulus by activating caspase-3 activity. In the investigated model system, DOPET is quantitatively converted into its methylated derivative, endowed with a radical scavenging ability comparable to that of its parent compound. These findings are in line with the hypothesis that the oxidative stress plays a major role in mediating the UVA-induced protein damage. Results suggest that DOPET may exerts differential effects on melanoma cells according to the dose employed and this must always be taken into account when olive oil-derived large consumer products, including cosmetics and functional foods, are employed.
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PMID:Hydroxytyrosol, a natural antioxidant from olive oil, prevents protein damage induced by long-wave ultraviolet radiation in melanoma cells. 1574 87

Advanced melanoma is difficult to treat, in part because of greater resistance to therapy compared with other cancer types. The mechanisms underlying this resistance are not well-understood. One factor that is reported to be involved in melanoma cell survival is PAX3, a transcription factor normally expressed during embryonic development, and which is critically required for development of neural crest-derivatives, including skin melanocytes. PAX3 expression is deregulated in primary melanomas and most melanoma cell lines. Here we have investigated whether targeting PAX3 expression in melanoma cell lines together with chemotherapeutic treatment increases susceptibility to therapeutic cell death. Using PAX3-specific antisense oligodeoxynucleotides (PAX3-AS) to treat melanoma cell lines in vitro, we showed dose-dependent reduction of proliferation of melanoma cells, and induction of apoptosis compared with control treatments. Induction of apoptosis was accompanied by the induction of active caspase-3 in UACC62 and M14 cells, and p53 protein in UACC62 cells. Treatment of melanoma cells with cisplatin induces DNA damage and cytotoxicity, which is thought to be via p53-dependent and -independent mechanisms. Treatment of either p53 mutant (M14) or wild-type (UACC62) melanoma cells with cisplatin, and varying doses of PAX3-AS, resulted in percentages of cells undergoing apoptosis equivalent to the sum of the individual treatments, irrespective of mutation status [e.g., UACC62, 43.8% (1 micromol/L PAX3-AS), 30.1% (20 micromol/L cisplatin), 69.6% (PAX3-AS + cisplatin); M14, 12.6% (1 micromol/L PAX3-AS), 41.5% (40 micromol/L cisplatin), 50.2% (PAX3-AS + cisplatin)]. These data suggest that treatment of melanoma cells with PAX3-AS complements cytotoxicity induced by cisplatin.
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PMID:Transfection of melanoma cells with antisense PAX3 oligonucleotides additively complements cisplatin-induced cytotoxicity. 1595 57

GTPase ras-related C3 botulinum toxin substrate 1 (Rac1) plays a role in various cellular processes pertinent to cancer development. In the present study, we investigated the molecular mechanisms underlying apoptosis regulation by Rac1 through functional proteomic analysis of three human melanoma M14 cell lines stably transfected with constitutively active Rac1V12, dominant negative Rac1N17, and empty vector (pIRES), respectively. We found that paclitaxel evoked apoptosis in the melanoma cell lines through the intrinsic (mitochondria) pathway in a caspsae-3-dependent manner. Compared to the Rac1pIRES and Rac1V12 cells, Rac1N17 cells were more resistant to paclitaxel-triggered caspase-3 activation and apoptosis. Protein composition comparisons amongst the three cell lines identified two peptide spots of interest. One was Hsp27, which was upregulated in Rac1N17 cells as assessed in our gel image interpretation, PMF and Western blot analysis. The other was identified as SR-25 protein (also known as the ADP-ribosylation factor-like factor 6-interacting protein 4; ARL6IP4) using PMF, which was separated only from the Rac1N17 cells under the experimental conditions. Moreover, knockdown of the protein level of Hsp27 using small interfering RNA in Rac1N17 cells significantly increased the paclitaxel-elicited caspase-3 activation and apoptosis. In conclusion, our results implicate that Hsp27 and SR-25 are mediators in Rac1 signaling pathway(s). It appears that the dominant negative Rac1N17 reduces the apoptosis sensitivity toward paclitaxel in the melanoma cells through upregulation of Hsp27, which inhibits its down stream drug-elicited caspase-3 activation.
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PMID:Dominant negative Rac1 attenuates paclitaxel-induced apoptosis in human melanoma cells through upregulation of heat shock protein 27: a functional proteomic analysis. 1795 76

In humans both UV-A and UV-B can cause gene mutations and suppress immunity, which leads to skin cancer, including melanoma. Inhibition of reactive oxygen species (ROS) and reactive nitrogen species (RNS) appears particularly promising as ROS and RNS production by both UV-A and UV-B contributes to inflammation, immunosuppression, gene mutation and carcinogenesis. We evaluated the effect of two lichen compounds, sphaerophorin (depside) and pannarin (depsidone) on pBR322 DNA cleavage induced by hydroxyl radicals (()OH), and by nitric oxide (NO), and their superoxide anion (O(2)(-)) scavenging capacity. In addition, we investigated the growth inhibitory activity of these compounds against human melanoma cells (M14 cell line). Sphaerophorin and pannarin showed a protective effect on plasmid DNA and exhibited a superoxide dismutase like effect. The data obtained in cell culture show that these lichen metabolites inhibit the growth of melanoma cells, inducing an apoptotic cell death, demonstrated by the fragmentation of genomic DNA (COMET and TUNEL Assays) and by a significant increase of caspase-3 activity, and correlated, at least in part, to the increase of ROS generation, These results confirm the promising biological properties of sphaerophorin and pannarin and encourage further investigations on their molecular mechanisms.
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PMID:Lichen metabolites prevent UV light and nitric oxide-mediated plasmid DNA damage and induce apoptosis in human melanoma cells. 1872 17

Members of the family Anacardiaceae are known to contain a number of biologically active substances, such as phenolic lipids, alkyl-catechols and alkyl-resorcinols. In the present study, human cancer cell lines, DU-145 cells (androgen-insensitive prostate cancer cells), KB cells (human epidermoid cells), and human melanoma cell line, M14, were treated for 72 h with 0.59-9.5 microM litreol (3-[pentadecyl-10-enyl-catechol]), a alkyl-catechol isolated from Lithraea caustica (Molina) Hook. & Arn. The results showed, for the first time, that litreol inhibited cancer cell viability in a dose-dependent manner. In addition, the treatment with this compound at 0.59-1.18 microM concentrations induced apoptotic cell death, demonstrated by the fragmentation of genomic DNA and by a significant increase of caspase-3 activity. The significant production of reactive oxygen species (ROS) evidenced in these experimental conditions could trigger the apoptosis cascades. Taken together, these results demonstrate that litreol attenuate the growth of human cancer cells, at least in part, triggering an apoptotic process, and they may offer a further impulse to the development of its analogues with more potent efficacy against human cancer cells.
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PMID:Effect of litreol on the viability of human cancer cells. 1900 65

The objective of this study is as follows. Inhibitor of growth (ING) 4 is a novel member of the ING family. It has been thought to play an inhibitory role in several malignancies through its involvment in gene transcription, apoptosis, cell cycle control, and tumor angiogenesis. The involvement of ING4 in melanomagenesis remains unknown. The purpose of this study was to investigate the inhibitory effects of ING4 on melanoma and its mechanisms. The method used was to construct recombinant plasmid pcDNA3.1-ING4 and transfect it into the human melanoma cell line M14. The effects and mechanisms of ING4 on proliferation and apoptosis of M14 cells were analyzed in vitro according to MTT assay, colony formation assay, and TUNEL assay. The detection of the expression of cell cycle or apoptosis regulators in transfected M14 cells was carried out by western blot analysis. Moreover, the level of ING4 in melanoma tissues was examined by immunohistochemistry. The expression of ING4 was markedly reduced in cutaneous melanoma tissues. Overexpression of ING4 could induce growth suppression and apoptosis enhancement in M14 cells, and also induce the upregulation of p27, Bax and Cyt-c, and the downregulation of cyclinD1, SKP2, Bcl-2, and caspase-3. In conclusion, ING4, as a novel tumor suppressor, has a potential role in growth suppression and apoptosis enhancement of melanoma M14 through the activation of the mitochondrial-induced apoptotic pathway and the hindrance of cell cycle progression. The deregulation of ING4 might be involved in melanomagenesis.
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PMID:Inhibitor of growth 4 is involved in melanomagenesis and induces growth suppression and apoptosis in melanoma cell line M14. 1943 Apr 1

Many Genista species (Leguminosae), containing isoflavones as biologically active substances, show interesting biological properties such as hypoglycemic, antiinflammatory, antiulcer, spasmolytic, antioxidant, estrogenic and cytotoxic activity against different human cancer cell lines. In this work, we describe the chemical composition of the methanolic extracts from aerial parts of Genista sessilifolia DC. and Genista tinctoria L., and their biological activity testing the effect on pBR322 DNA cleavage induced by hydroxyl radicals (*OH), generated from UV-photolysis of hydrogen peroxide (H(2)O(2)) and by nitric oxide (NO). In addition, we investigated the growth inhibitory activity of these natural products against human melanoma cell line (M14). The extracts of G. sessilifolia and G. tinctoria, for their isoflavone components, showed a protective effect on UV light and nitric oxide-mediated plasmid DNA damage, and inhibited the growth of melanoma cells. The data of the present study also suggest that these natural products could trigger apoptotic death in M14 cells. In fact, a high DNA fragmentation (COMET assay) and a significant increase of caspase-3 activity, not correlated to LDH release, a marker of membrane breakdown, occurred in melanoma cells exposed to these extracts. The significant production of reactive oxygen species (ROS) evidenced in these experimental conditions could contribute to trigger the apoptosis cascades.
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PMID:Genista sessilifolia DC. and Genista tinctoria L. inhibit UV light and nitric oxide-induced DNA damage and human melanoma cell growth. 1949 19


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