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Query: UNIPROT:P42574 (
caspase-3
)
45,978
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
UCN-01, a selective inhibitor of protein kinase C, is known to inhibit the growth of cancer cells. Although it is currently undergoing clinical evaluation, information about its effect on human
colon cancer
is limited and the mechanism responsible is lacking. The objective of this study was to examine the cytotoxicity of UCN-01 to human
colon cancer
cells in vitro and its effect on the apoptotic molecules. HT-29, a radiation- and chemotherapy-resistant human
colon cancer
cell, was used in the study. Cell death/apoptosis was determined by the MTT assay and DNA fragmentation measurement. NF-kappaB activity was measured by an enzyme immunoassay method. Western blot was employed to examine the expression of relevant apoptotic molecules. The result showed that UCN-01 could induce apoptosis of human
colon cancer
cells in a time- and dose-dependent manner. It markedly reduced the expression of Bcl-xL, but enhanced the level of p38 MAPK. In addition to Bcl-xL and p38 MAPK, UCN-01 also increased both
caspase-3
and peroxisome proliferator activated receptor gamma protein levels. HT-29 cells transfected with exogenous Bcl-xL showed a significant increase in NF-kappaB activity and prevented apoptosis induced by UCN-01. The overexpression of Bcl-xL also reversed other relevant molecular changes observed in UCN-01-treated cells. In conclusion, UCN-01 exerted an antitumor effect in human
colon cancer
cells by inducing apoptosis. The mechanism responsible appeared to be related to reduction of Bcl-xL and increased p38 MAPK. The overexpression of Bcl-xL can significantly prevent apoptosis induced by UCN-01.
...
PMID:Induction of colon cancer cell death by 7-hydroxystaurosporine (UCN-01) is associated with increased p38 MAPK and decreased Bcl-xL. 1455 11
Since ethacrynic acid (EA), an SH modifier as well as glutathione S-transferase (GST) inhibitor, has been suggested to induce apoptosis in some cell lines, its effects on a human
colon cancer
cell line DLD-1 were examined. EA enhanced cell proliferation at 20-40 microM, while it caused cell death at 60-100 microM. Caspase inhibitors did not block cell death and DNA ladder formation was not detected. Poly(ADP-ribose) polymerase, however, was cleaved into an 82-kDa fragment, different from an 85-kDa fragment that is specific for apoptosisis. The 82-kDa fragment was not recognized by antibody against PARP fragment cleaved by
caspase 3
. N-Acetyl-L-cysteine (NAC) completely inhibited EA-induced cell death, but 3(2)-t-butyl-4-hydroxyanisole or pyrrolidinedithiocarbamate ammonium salt did not. Glutathione (GSH) levels were dose-dependently increased in cells treated with EA and this increase was hardly affected by NAC addition. Mitogen-activated protein kinase (MAPK) kinase (MEK) 1, extracellular signal-regulated kinase (ERK) 1 and GST P1-1 were increased in cells treated with 25-75 microM EA, while c-Jun N-terminal kinase (JNK) 1 and p38 MAPK were markedly decreased by 100 microM EA. NAC repressed EA-induced alterations in these MAPKs and GST P1-1. p38 MAPK inhibitors, SB203580 and FR167653, dose-dependently enhanced EA-induced cell death. An MEK inhibitor, U0126, did not affect EA-induced cell death. These studies revealed that EA induced cell death concomitantly with a novel PARP fragmentation, but without DNA fragmentation. p38 MAPK was suggested to play an inhibitory role in EA-induced cell death.
...
PMID:Characterization of cell death induced by ethacrynic acid in a human colon cancer cell line DLD-1 and suppression by N-acetyl-L-cysteine. 1455 62
Epidemiological and experimental carcinogenesis studies provide evidence that components of garlic (Allium sativum) have anticancer activity. We recently reported that the garlic derivative S-allylmercaptocysteine (SAMC) inhibits growth, arrests cells in G(2)-M, and induces apoptosis in human
colon cancer
cells (Shirin et al., Cancer Res., 61: 725-731, 2001). Because a fraction of the SAMC-treated cells are specifically arrested in mitosis, we examined the mechanism of this effect in the present study. Immunofluorescent microscopy revealed that the treatment of SW480 cells or NIH3T3 fibroblasts with 150 micro M SAMC (the IC(50) concentration) caused rapid microtubule (MT) depolymerization, MT cytoskeleton disruption, centrosome fragmentation and Golgi dispersion in interphase cells. It also induced the formation of monopolar and multipolar spindles in mitotic cells. In vitro turbidity assays indicated that SAMC acted directly on tubulin to cause MT depolymerization, apparently because it interacts with -SH groups on tubulin. To investigate the signaling pathways involved in SAMC-induced apoptosis, we assayed c-Jun NH(2)-terminal kinase (JNK) activity and found that treatment with SAMC caused a rapid and sustained induction of JNK activity. The selective JNK inhibitor SP600125 inhibited the early phase (24 h) but not the late phase (48 h and later) of apoptosis induced by SAMC. Expression of a dominant-negative mutant of JNK1 in SW480 cells inhibited apoptosis induced by SAMC at 24 h but had no protective effect at 48 h. JNK1(-/-) mouse embryonic fibroblasts were resistant to SAMC-induced apoptosis at 24 h but not at 48 h. On the other hand, the inhibition or abrogation of JNK1 activity did not inhibit the G(2)-M arrest induced by SAMC. SAMC also activated
caspase-3
. The general caspase inhibitor z-VAD-fmk inhibited both early and late phases of apoptosis induced by SAMC. We conclude that the garlic-derived compound SAMC exerts antiproliferative effects by binding directly to tubulin and disrupting the MT assembly, thus arresting cells in mitosis and triggering JNK1 and
caspase-3
signaling pathways that lead to apoptosis.
...
PMID:Induction of apoptosis by the garlic-derived compound S-allylmercaptocysteine (SAMC) is associated with microtubule depolymerization and c-Jun NH(2)-terminal kinase 1 activation. 1458 80
Retinoids are natural and synthetic derivatives of vitamin A that have great promise for cancer therapy and chemoprevention. Of the retinoids developed so far, 4-(N-hydroxyphenyl)retinamide (4-HPR or fenretinide) appears to have the best therapeutic potential in vitro and in vivo and is currently being tested in clinical trials for cancer prevention and therapy. To develop other potentially potent antitumor agents, we synthesized 85 retinoid derivatives. In an initial screening of these synthetic retinoids using the HCT116
colon cancer
cell line, we found that 4-amino-2-(butyrylamino)phenyl(2E,4E,6E,8E)-3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexenyl)-2,4,6,8-nonatetraenoate (ABPN or CBG41) induced the greatest growth inhibition, with an IC(50) value of 0.6 microM. Subsequent studies in other cancer cell lines indicated that ABPN was much more growth-inhibitory than all-trans retinoic acid or 4-HPR. Compared to 4-HPR, ABPN induced 5.5- to 70.0-fold more growth inhibition in most cancer cells, with the exception of gynecologic cancer cells. In these cells, the antiproliferative effect was only 1.5- to 2.8-fold more than 4-HPR. We examined the molecular mechanism underlying the difference in growth inhibition between 4-HPR and ABPN. DAPI staining, DNA fragmentation, FACS and Western blotting analyses suggest that ABPN induced apoptosis by activating
caspase-3
and -8, which may result in increased PARP cleavage. Unlike 4-HPR, ABPN activated all 3 RAR isotypes to an extent similar to AtRA. In addition, ABPN significantly inhibited AP-1 transcriptional activity and thus greatly suppressed the expression of the matrix metalloproteinase -1, -2 and -3 genes, which are involved in tumor invasion. These results suggest that ABPN may be a promising retinoid derivative offering not only enhanced cytotoxicity, but also increased inhibition of tumor invasiveness.
...
PMID:Novel retinoic acid derivative ABPN has potent inhibitory activity on cell growth and apoptosis in cancer cells. 1460 Oct 67
beta-sitosterol, a main dietary phytosterol found in plants, may have the potential for prevention and therapy for human cancer. The purpose of the present study was to examine the effect of beta-sitosterol on the growth of HT116 human
colon cancer
cells. Treatment with beta-sitosterol resulted in a dose-dependent growth inhibition coupled with the characteristic morphological features of apoptosis and with the increase of a sub-G1 cell population. Apoptosis-inducing concentrations of beta-sitosterol induced
caspase-3
and caspase-9 activation accompanied by proteolytic cleavage of poly(ADP-ribose)-polymerase. In addition, beta-sitosterol-induced apoptosis in HT116 cells was associated with a decreased expression of the anti-apototic Bcl-2 protein and mRNA and a concomitant increase of the pro-apototic Bax protein and mRNA, and with release of cytochrome c from the mitochondria into the cytosol. beta-sitosterol treatment also inhibited the expression of cIAP-1 without significant changes in the level of cIAP-2. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of beta-sitosterol.
...
PMID:Induction of Bax and activation of caspases during beta-sitosterol-mediated apoptosis in human colon cancer cells. 1461 38
The efficacy of antineoplastic compounds can depend heavily on the genetic background of the cells exposed to the drugs. This becomes evident by the fact that HT-29 human
colon cancer
cells but not primary murine nontransformed colonocytes are efficiently submitted to apoptosis by the flavonoid flavone. By determining
caspase-3
activation, plasma membrane disintegration, and nuclear fragmentation, we show here that flavone also does not promote apoptosis in preneoplastic NCOL-1 colonocytes derived from a nontransformed human biopsy specimen. In clear contrast, the antitumor drug camptothecin potently induces apoptosis in NCOL-1 cells associated with a specific down-regulation of the antiapoptotic factor bcl-XL at the mRNA and protein levels and with the activation of the mitochondrial apoptosis pathway. Confocal microscopy revealed an increased production of superoxide anion radicals in the mitochondria of NCOL-1 cells that preceded the apoptotic events. However, in the case of flavone, the mitochondrial oxygen radicals were effectively scavenged by physiological concentrations of nitric oxide (NO), whereas in the case of camptothecin, the available nitric oxide was rapidly scavenged by the production of large quantities of cytosolic superoxide anions. Increasing the levels of nitric oxide inside NCOL-1 cells by sodium nitroprusside prevented the apoptosis induction by camptothecin. Reducing the levels of nitric oxide by using the NO synthase inhibitor, Nomega-nitro-l-arginine methyl ester in NCOL-1 cells or using HT-29 cells that intrinsically have low NO levels enabled flavone to trigger the apoptosis pathway. In conclusion, our studies demonstrate that the intracellular levels of nitric oxide significantly change the apoptotic response to antineoplastic agents in colonic cells.
...
PMID:Nitric oxide levels in human preneoplastic colonocytes determine their susceptibility toward antineoplastic agents. 1464 80
2'-hydroxycinnamaldehyde (HCA) has been shown to have inhibitory effects on farnesyl protein transferase in vitro, angiogenesis, and tumor cell growth. However, mechanism for these inhibitions remains unknown. As a derivative of HCA, BCA (2'-benzoyl-oxycinnamaldehyde) was synthesized by replacing hydroxyl group with benzoyl-oxyl group. When p53-mutated cancer cell lines (MDA-MB-231 breast cancer cell and SW620
colon cancer
cell) were treated with 10 microM HCA or BCA, it induced growth arrest and apoptosis of tumor cells. Markers of apoptosis such as degradations of chromosomal DNA and poly(ADP-ribose) polymerase and activation of
caspase-3
were detected after HCA or BCA treatment. BCA-induced apoptosis was blocked by pretreatment of cells with anti-oxidants, glutathione, or N-acetyl-cysteine. In addition, BCA-induced activation of
caspase-3
and degradation of poly(ADP-ribose) polymerase were abolished by pretreatment of cells with the anti-oxidants. These results suggest that reactive oxygen species are major regulator of BCA-induced apoptosis. HCA or BCA-induced accumulation of reactive oxygen species was detected by using DCF-DA, an intracellular probe of oxidative stress. Furthermore, when BCA (100 mg/kg) was administrated intraperitoneally or orally into a nude mouse, it inhibited >88 or 41% of tumor growth, respectively, without any detectable weight change. These results suggest that BCA is a good drug candidate for cancer therapy.
...
PMID:2'-benzoyloxycinnamaldehyde induces apoptosis in human carcinoma via reactive oxygen species. 1466 Jun 55
Heparin/heparan sulfate interacting protein (HIP, also known as ribosome protein L29) is involved in cell-cell and cell-extracellular matrix interactions and influences cell proliferation, migration and differentiation. In the present study, we investigated the role of HIP in anticancer drug-induced apoptosis. Both
colon cancer
HCT-116 and HT-29 cells showed dose-dependent down-regulation of HIP expression when treated with sodium butyrate. The down-regulation was negatively correlated with the percentage of apoptotic cells (R = -0.955, P = 0.03 and R = -0.792, P = 0.06 for HCT-116 and HT-29 cells, respectively). The correlation between HIP expression and apoptosis in HCT-116 cells was also evident in the differential expression of HIP in the floating and adherent cell populations. Most apoptotic cells were distributed in the floating population. HIP expression in this population was approximately 30% lower than adherent and untreated control cells. HIP expression in HCT-116 cells was also significantly decreased in parallel with apoptosis after treatment with 50 micro M camptothecin and 20 micro M 5-fluorouracil. This indicates that the down-regulation of HIP may be a general phenomenon in anticancer drug-induced apoptosis. The down-regulation of HIP occurred in the early phase of apoptosis, in parallel with the activation of
caspase-3
and the externalization of phosphatidylserine. The functional significance of HIP in apoptosis was shown by knocking down the expression of HIP using small interfering RNA. A 50% reduction in HIP expression was sufficient to increase the percentage of apoptotic cells (from 11 to 20%) and increase the sensitivity of the cells to apoptosis induced by 1 mM butyrate by 60%. These results indicate that HIP may play an important role in anticancer drug-induced apoptosis.
...
PMID:Heparin/heparan sulfate interacting protein plays a role in apoptosis induced by anticancer drugs. 1472 79
Although a high alimentary intake of antioxidant vitamins such as ascorbic acid may play an important role in cancer prevention, a high level of antioxidants may have quite different effects at different stages of the transformation process. In cancer development, the resistance of cells to apoptosis is one of the most crucial steps. We have tested the effects of ascorbic acid on apoptosis in HT-29 human colon carcinoma cells when induced by two potent apoptosis inducers, the classical antitumor drug camptothecin or the flavonoid flavone. Apoptosis was assessed based on
caspase-3
-like activity, plasma membrane disintegration and finally nuclear fragmentation and chromatin condensation. Ascorbic acid dose-dependently inhibited the apoptotic response of cells to camptothecin and flavone. RT-PCR analysis and western blot analysis revealed that ascorbic acid specifically blocked the decrease of bcl-X(L) by camptothecin or flavone. An increased generation of mitochondrial O(2)(-.) precedes the down-regulation of bcl-X(L) by camptothecin and flavone and ascorbic acid at a concentration of 1 mM prevented the generation of this reactive oxygen species. In conclusion, ascorbic acid functions as a potent antioxidant in mitochondria of human
colon cancer
cells and thereby blocks drug-mediated apoptosis induction allowing cancer cells to become insensitive to chemotherapeutics.
...
PMID:Ascorbic acid suppresses drug-induced apoptosis in human colon cancer cells by scavenging mitochondrial superoxide anions. 1475 75
In a search for new anticancer agents, we identified that 2[[3-(2,3-dichlorophenoxy) propyl]amino]ethanol (2,3-DCPE) induced apoptosis more effectively in various cancer cells than in normal human fibroblasts. We further evaluated the cell-killing effects of this compound in vitro in several human cancer cell lines and normal human fibroblasts. A cell viability assay showed that IC(50)s for human
colon cancer
cell lines LoVo and DLD-1, for human lung cancer cell lines H1299 and A549, and for normal human fibroblasts were 0.89, 1.95, 2.24, 2.69, and 12.6 micro M, respectively. Subsequent studies revealed that 2,3-DCPE could cause cleavage of caspase-8,
caspase-3
, caspase-9, and poly(ADP-ribose) polymerase and release of cytochrome c in cancer cells but not in normal human fibroblasts. Our data also showed that 2,3-DCPE attenuated the protein level of Bcl-XL and that apoptosis induction by 2,3-DCPE could be blocked by enforced overexpression of Bcl-XL. Our results suggest that 2,3-DCPE might be a potential new anticancer agent.
...
PMID:Induction of apoptosis and down-regulation of Bcl-XL in cancer cells by a novel small molecule, 2[[3-(2,3-dichlorophenoxy)propyl]amino]ethanol. 1487 45
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