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

We assessed the ability of cryptophycin 52 (LY355703), a novel antimicrotubule, to induce growth arrest and apoptosis in prostate cancer cell lines and investigated potential molecular mechanisms of death. LNCaP (androgen-dependent) and DU-145 (androgen-independent) cells accumulated in G(2)-M phase of the cell cycle and progressively acquired sub-G(0)-G(1) DNA content after 48 h of exposure to cryptophycin 52 (1-10 pM). Induction of apoptosis was confirmed by DNA ladder formation and detection of cytoplasmic nucleosomes. PC-3 (androgen-independent) cells were less responsive to cryptophycin 52-induced death. Apoptosis was associated with proteolytic processing and activation of the caspase-3-like subfamily proteins caspase-3 and caspase-7 and cleavage of the caspase substrate poly(ADP-ribose) polymerase. The pan-caspase inhibitor BOC-Asp(OMe)-fluoromethylketone effectively reduced cryptophycin 52-induced caspase-3-like protease activity and apoptosis in DU-145 cells. In contrast, BOC-Asp(OMe)-fluoromethylketone did not inhibit apoptosis induction in LNCaP cells by cryptophycin 52, even though both cryptophycin 52-induced caspase-3-like activity and staurosporine-induced death were blocked under identical conditions. Cryptophycin 52 induced phosphorylation of c-raf1 and bcl-2 and/or bcl-x(L) to comparable levels in all cell lines studied, and LNCaP cells overexpressing bcl-2 were more resistant to cryptophycin 52-induced apoptosis. Up-regulation of p53, bax, and p21 expression was induced in wild-type p53-expressing LNCaP cells only after cryptophycin 52 exposure. A sustained increase in c-Jun NH(2)-terminal kinase phosphorylation was also observed, the levels of which strongly correlated with apoptosis. We conclude that apoptosis induced by cryptophycin 52 in prostate cancer cells is androgen status independent, cell type specific for caspase requirement, modulated by the bcl-2 family, linked to but not dependent on p53, and strongly correlated with c-Jun NH(2)-terminal kinase phosphorylation. Cryptophycin 52-induced apoptosis in prostate cancer cells is therefore associated with multiple cell line-specific alterations in apoptosis-associated proteins and pathways.
...
PMID:The novel antimicrotubule agent cryptophycin 52 (LY355703) induces apoptosis via multiple pathways in human prostate cancer cells. 1247 8

Calcitriol [1alpha,25-dihydroxyvitamin D3] is the natural ligand of the vitamin D receptor (VDR). Using cultured prostate cancer (PC) cell lines, LN-CaP and ALVA-31, we studied the effects of 1alpha,25(OH)2-Vitamin D3 (VD3) on expression of several apoptosis-regulating proteins including: (a) Bcl-2 family proteins (Bcl-2, Bcl-X(L), Mcl-1, Bax, and Bak); (b) the heat shock protein 70-binding protein BAG1L; and (c) IAP family proteins (XIAP, cIAP1, and cIAP2). VD3 induced decreases in levels of antiapoptotic proteins Bcl-2, Bcl-X(L), and Mcl-1, BAG1L, XIAP, cIAP1, and cIAP2 (without altering proapoptotic Bax and Bak) in association with increases in apoptosis. In contrast to VDR-expressing LN-CaP and ALVA-31 cells, VDR-deficient prostate cancer line Du-145 demonstrated no changes in apoptosis protein expression after treatment with VD3. In sensitive PC cell lines, VD3 activates downstream effector protease, caspase-3, and upstream initiator protease caspase-9, the apical protease in the mitochondrial ("intrinsic") pathway for apoptosis, but not caspase-8, an initiator caspase linked to an alternative ("extrinsic") apoptosis pathway triggered by cytokine receptors. VD3 induced declines in antiapoptotic proteins and also stimulated cytochrome c release from mitochondria by a caspase-independent mechanism. Moreover, apoptosis induction by VD3 was suppressed by overexpressing Bcl-2, a known blocker of cytochrome c release, whereas the caspase-8 suppressor CrmA afforded little protection. Thus, VD3 is capable of inhibiting expression of multiple antiapoptotic proteins in VDR-expressing prostate cancer cells, leading to activation of the mitochondrial pathway for apoptosis.
...
PMID:Apoptosis induction by 1alpha,25-dihydroxyvitamin D3 in prostate cancer. 1247 63

The terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labelling (TUNEL) technique has been extensively used for the detection and quantification of apoptosis in histological tissue sections. However, the interpretation and specificity of this assay have been controversial. With accumulating knowledge of the molecular mechanisms of cell death and the discovery of the caspases as key mediators of apoptosis, more direct and earlier measurements of apoptosis in tissue sections have emerged. This study, using antibodies that specifically recognize activated caspase-3 and caspase-cleaved cytokeratin (CK) 18, evaluated whether immunohistochemical stains would improve the detection and quantification of apoptosis in tissue sections, compared with the TUNEL assay. Tumour xenografts of the prostate cancer cell line PC-3 were used as an example, since these tissues contain large numbers of cells undergoing apoptosis. Apoptotic cells were quantified and apoptotic indices were calculated by computer-assisted image analysis following identification of apoptotic cells by morphological analysis, the TUNEL assay, activated caspase-3 and cleaved CK18 immunohistochemistry. The results indicated that activated caspase-3 immunohistochemistry was an easy, sensitive, and reliable method for detecting and quantifying apoptosis in this model. An excellent correlation (R = 0.89) between the apoptotic indices obtained using activated caspase-3 and cleaved CK18 immunostaining was observed. A good correlation (R = 0.75) between the apoptotic indices obtained using activated caspase-3 immunostaining and the TUNEL assay was also found. Activated caspase-3 immunohistochemistry is therefore recommended for the detection and quantification of apoptosis in tissue sections.
...
PMID:Comparison of immunohistochemistry for activated caspase-3 and cleaved cytokeratin 18 with the TUNEL method for quantification of apoptosis in histological sections of PC-3 subcutaneous xenografts. 1253 35

To clarify the roles of the X-linked inhibitor of apoptosis protein (XIAP), we investigated the effects of XIAP overexpression on taxol-induced cell growth arrest and apoptosis in the prostate cancer cell line (LNCaP). After the transfection of XIAP cDNA into LNCaP cells, we established clonal cell lines that overexpressed XIAP and examined the taxol effects on growth and apoptosis by 2-(4-lodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt and flow cytometric analysis. The effects of XIAP overexpression on caspase-3 were examined by immunoblot analysis and activity assay. The interaction between XIAP and caspase-3 in LNCaP cells was examined by cotransfection with myc-XIAP and caspase-3-HA cDNAs followed by immunoprecipitation and immunoblot analysis. Large amounts of XIAP were expressed in the established cell lines. Although the growth rates were reduced in a dose- and time-dependent manner by taxol, these effects were significantly decreased in XIAP stably overexpressing cell lines. In addition, we found that taxol treatment induced the cleavage of pro-caspase-3, followed by apoptosis, and that the overexpression of XIAP inhibited apoptosis by attenuating the cleavage of pro-caspase-3 and caspase-3 activity. Interestingly, XIAP bound to pro-caspase-3 in LNCaP cells transiently cotransfected with myc-XIAP and caspase-3-HA cDNAs, and this interaction was inhibited by taxol treatment. These results suggest that the overexpression of XIAP inhibits taxol-induced apoptosis through the decrease of caspase-3 activity and inhibition of the processing of pro-caspase-3.
...
PMID:The X-linked inhibitor of apoptosis protein inhibits taxol-induced apoptosis in LNCaP cells. 1262 62

For hormone resistant prostate cancer (HRPC), chemotherapy is used but the mortality is 100% with a mean survival time of 7-8 months. Our previous studies have shown the chemotherapeutic effect of ciprofloxacin in bladder cancer. At doses 50-400 micro g/ml ciprofloxacin, the concentrations that are normally achieved at doses currently used for the treatment of anti-bacterial infections, inhibited bladder cancer cell growth and induced S/G2M arrest with modulation of key cell cycle regulatory genes and ultimately activated apoptotic processes. In this study, we investigated the effect of ciprofloxacin on androgen independent prostate carcinoma, PC3 cells and compared our results with non-tumorigenic prostate epithelial cells. The main advantage of this fluroquinolone antibiotic is its relative non-toxicity as compared to current chemotherapy, which is not very effective, for the treatment of advanced hormone resistant prostate cancer. PC3 cells as well as normal prostate epithelial cells (MLC8891) were treated with 25-400 micro g/ml ciprofloxacin, and cell counting was done during 3 days of treatment. The cell death was determined using DAPI staining of cell nuclei, 7AAD-staining followed by flow cytometric analysis as well as by activation of caspase-3, a member of the ICE family of enzymes involved in the apoptotic cascade. The cell lysates were analyzed by immunoblotting techniques for the expression of key genes targeted by ciprofloxacin (p21WAF1, Bax and Bcl-2). Translocation of bax was visualized using a fluorescence staining procedure followed by laser confocal microscopic imaging. Treatment of prostate cancer cells with ciprofloxacin resulted in a dose- and time-dependent inhibition of cell growth (70-100% with 50-400 micro g/ml of the drug). There was a concomitant induction of cell cycle arrest at the S and G2/M phases of the cell cycle as well as induction of apoptosis. The CDK inhibitor p21WAF1 was down-regulated as early as 12 h following ciprofloxacin treatment (100-200 micro g/ml for 12-24 h). There was a significant increase in the Bax/Bcl-2 ratio with translocation of Bax, a pro-apoptotic protein, to mitochondria with concomitant activation of caspase 3. These results suggest the potential usefulness of the fluroquinolone, ciprofloxacin as a chemotherapeutic agent for advanced prostate cancer. The fluroquinolone ciprofloxacin showed anti-proliferative and apoptosis inducing activity on prostate cancer cells but not on non-tumorigenic prostate epithelial cells. These effects of ciprofloxacin were mediated by cell cycle arrest at S-G2/M phase of the cell cycle, Bax translocation to mitochondrial membrane and by increasing the Bax/Bcl-2 ratio in PC3 prostate cancer cells. Based on our in vitro results, further in-depth in vivo animal or human investigations are warranted.
...
PMID:Suppression of human prostate cancer cell growth by ciprofloxacin is associated with cell cycle arrest and apoptosis. 1263 69

p202, an interferon (IFN) inducible protein, is a phosphonuclear protein involved in the regulation of cell cycle, apoptosis, and differentiation. E2F1 belongs to the E2F family of proteins that are important cell cycle regulators in promoting cell growth. On the other hand, the deregulated expression of E2F1 also triggers apoptosis independent of p53 status. It has been well documented that p202 is able to inhibit cell growth by binding to E2F1 and abolishing the E2F1-mediated transcriptional activation of S-phase genes. However, it is not known whether E2F1-mediated apoptosis can be counteracted by p202 expression. Here, we show that E2F1-mediated apoptosis induced by the infection of an E2F1-expressing adenoviral vector (Ad-E2F1) was greatly diminished in p202-expressing prostate cancer cells. The E2F1-mediated caspase-3 activation was also reduced in p202-expressing cells infected with Ad-E2F1. Since caspase-3 is one of the E2F1 transcriptional targets, this result is consistent with the ability of p202 to inhibit the transcriptional activity of E2F1. Therefore, our results suggest a possible link between the IFN and E2F pathways in regulating apoptosis.
...
PMID:P202, an interferon-inducible protein, inhibits E2F1-mediated apoptosis in prostate cancer cells. 1264 90

Cancer chemopreventive effects of inositol hexaphosphate (IP6), a dietary constituent, have been demonstrated against a variety of experimental tumors, however, limited studies have been done against prostate cancer (PCA), and molecular mechanisms are not well defined. In the present study, we investigated the growth inhibitory effect and associated mechanisms of IP6 in advanced human PCA cells. Advanced human prostate carcinoma DU145 cells were used to study the anticancer effect of IP6. Flow cytometric analysis was performed for cell cycle progression and apoptosis studies. Western immunoblotting, immunoprecipitation and kinase assay were performed to investigate the involvement of G1 cell cycle regulators and their interplay, and end point markers of apoptosis. A significant dose- as well as time-dependent growth inhibition was observed in IP6-treated cells, which was associated with an increase in G1 arrest. IP6 strongly increased the expression of CDKIs (cyclin-dependent kinase inhibitors), Cip1/p21 and Kip1/p27, without any noticeable changes in G1 CDKs and cyclins, except a slight increase in cyclin D2. IP6 inhibited kinase activities associated with CDK2, 4 and 6, and cyclin E and D1. Further studies showed the increased binding of Kip1/p27 and Cip1/p21 with cyclin D1 and E. In down-stream of CDKI-CDK/cyclin cascade, IP6 increased hypophosphorylated levels of Rb-related proteins, pRb/p107 and pRb2/p130, and moderately decreased E2F4 but increased its binding to both pRb/p107 and pRb2/p130. At higher doses and longer treatment times, IP6 caused a marked increase in apoptosis, which was accompanied by increased levels of cleaved PARP and active caspase 3. IP6 modulates CDKI-CDK-cyclin complex, and decreases CDK-cyclin kinase activity, possibly leading to hypophosphorylation of Rb-related proteins and an increased sequestration of E2F4. Higher doses of IP6 could induce apoptosis and that might involve caspases activation. These molecular alterations provide an insight into IP6-caused growth inhibition, G1 arrest and apoptotic death of human prostate carcinoma DU145 cells.
...
PMID:Inositol hexaphosphate inhibits growth, and induces G1 arrest and apoptotic death of prostate carcinoma DU145 cells: modulation of CDKI-CDK-cyclin and pRb-related protein-E2F complexes. 1266 18

The p53 mutant 143Ala is a human temperature-sensitive mutant with two conformational states. To definitively determine whether the Fas signal transduction pathway and the function of the pathway are dependent on p53 status, we have established stable transfectants of p53 mutant 143Ala in two human cancer cell lines: H1299 (lung cancer line) and PC-3 (prostate cancer line), the native state of which contains null p53 status and can grow at 37 degrees C and 32.5 degrees C. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell cycle analysis showed inhibition of the growth of cells overexpressing p53 mutant 143Ala in the wild-type p53 form at 32.5 degrees C because of induction of G0/G1 arrest. Transfected cells had increased protein expression of p21, Fas, and MDM2 at the wild-type p53 conformation at 32.5 degrees C, but not in the mutant p53 form at 37 degrees C. However, there was no change in protein expression of FADD, FAP-1, Bcl-2, or Bax at 32.5 or 37 degrees C. Assays for apoptosis demonstrated that anti-Fas antibody CH-11 and FasL induced apoptosis only in cells that overexpress p53 mutant 143Ala at 32.5 degrees C with the wild-type p53 form. Both caspase-3 and caspase-8 activities were increased by anti-Fas antibody CH-11 only in cells at 32.5 degrees C with wild-type p53. Our results demonstrated that Fas-mediated apoptosis in H1299 and PC-3 cells expressing p53 mutant 143Ala occurred only with the wild-type p53 phenotype. These results support the hypothesis that Fas-mediated apoptosis is dependent, at least partially, on the presence of a functional wild-type p53 state. This model may be a useful tool for dissecting the specific interactions between wild-type p53 and the Fas signal transduction pathway in human cancer cells.
...
PMID:Fas-mediated apoptosis is dependent on wild-type p53 status in human cancer cells expressing a temperature-sensitive p53 mutant alanine-143. 1267 Sep

Identifying regulators of prostate cancer cell survival may lead to new therapeutic strategies for prostate cancer. We now report prevalent activation of transcription factor Stat5 in human prostate cancer and provide novel evidence that blocking activation of Stat5 in human prostate cancer cells leads to extensive cell death. Specifically, Stat5 was activated in 65% of human prostate cancer specimens examined based on nuclear location of tyrosine phosphorylated Stat5. Adenoviral gene delivery of a dominant-negative Stat5 mutant (DNStat5), but not wild-type Stat5, induced cell death of both the androgen-independent human prostate cancer cell line CWR22Rv and the androgen-sensitive LnCap cell line. Endogenous Stat5 was active in both CWR22Rv and LnCap cells. In contrast, only low levels of inactive Stat5 proteins were detected in the PC-3 cell line, which correlated with resistance to DNStat5-induced cell death. In CWR22Rv and LnCap cells, inhibition of Stat5 by expression of DNStat5 induced apoptotic cell death as judged from morphological changes, DNA fragmentation, and caspase-3 activation with evidence of a caspase-9-dependent mechanism. We propose that blocking Stat5 function may represent a novel therapeutic approach for prostate cancer.
...
PMID:Inhibition of transcription factor Stat5 induces cell death of human prostate cancer cells. 1271 22

Previous studies documented the ability of quinazoline-based alpha1-adrenoceptor antagonists to induce apoptosis in prostate cancer cells via an alpha 1-adrenoceptor-independent mechanism. In this study we investigated the molecular events initiating this apoptotic effect. Since transforming growth factor-beta 1 (TGF-beta 1) mediates prostate epithelial cell apoptosis, we hypothesised that the activation of the TGF-beta 1 pathway underlies the quinazoline-based apoptotic effect in prostate cancer cells. Treatment of the androgen-independent human prostate cancer cells PC-3 with doxazosin resulted in a strong caspase-3 activation within 24 h, whereas tamsulosin, a sulphonamide-based alpha 1-adrenoceptor antagonist, had no significant apoptotic effect against prostate cancer cells. To identify the molecular components involved in this quinazoline-mediated apoptosis, cDNA microarray analysis of PC-3 prostate cancer cells treated with doxazosin (3 h) was performed. Induced expression of several genes was observed including p21(WAF-1) and I kappa B alpha (inhibitor of NF-kappa B alpha). Relative quantitative reverse transcription-polymerase chain reaction analysis revealed induction of several TGF-beta1 signalling effectors: Induction of mRNA for Smad4 and the TGF-beta1-regulated apoptosis-inducing transcription factor TGF-beta1-inducible early gene (TIEG1) was detected within the first 6 h of doxazosin treatment. Upregulation of I kappa B alpha at both the mRNA and protein level was also detected after 6 h of treatment. Furthermore, doxazosin resulted in a considerable elevation in Smad4 and TIEG protein expression (6 h). A 'latent' increase in TGF-beta mRNA expression was detected after 48 h of treatment. These findings suggest that the quinazoline-based doxazosin mediates prostate cancer apoptosis by initially inducing the expression of TGF-beta1 signalling effectors and subsequently I kappa B alpha. The present study provides an initial insight into the molecular targets of the apoptotic action of quinazolines against prostate cancer cells.
...
PMID:Quinazoline-based alpha 1-adrenoceptor antagonists induce prostate cancer cell apoptosis via TGF-beta signalling and I kappa B alpha induction. 1277 31


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>