Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P42574 (
caspase-3
)
45,978
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The proteolytic cleavage pathways of
E-cadherin
endogenously expressed in MDCK (Madin-Darby canine kidney) cells were characterized in cells treated with antimycin A and deoxyglucose to examine transmembrane protein processing under cellular stress.
E-cadherin
is a type I transmembrane protein which operates as the cell adhesion molecule component of the adherens junction, a complex of proteins involved in epithelial tissue development and integrity. We now demonstrate that treatment of MDCK cells with antimycin A and deoxyglucose activates caspase mediated pathways that cleave
E-cadherin
.
E-cadherin
is cleaved into two major fragments, with the sizes predicted by the location of a
caspase-3
cleavage consensus sequence. Cleavage of
E-cadherin
and deposition of the C-terminal fragment into the cytoplasm are inhibited by the caspase inhibitor DEVD-CHO. Thus, a major mechanism for
E-cadherin
cleavage and dissolution of the adherens junction under antimycin/deoxyglucose treatment is caspase mediated, initiated by activation of an apoptosis pathway.
...
PMID:Biochemical processing of E-cadherin under cellular stress. 1285 42
It is well known that inflammatory conditions of the intestinal mucosa result in compromised barrier function. Inflammation is characterized by an influx into the mucosa of immune cells that influence epithelial function by releasing proinflammatory cytokines such as IFN-gamma and TNF-alpha. Mucosal barrier function is regulated by the epithelial apical junctional complex (AJC) consisting of the tight junction and the adherens junction. Since the AJC regulates barrier function, we analyzed the influence of IFN-gamma and TNF-alpha on its structure/function and determined the contribution of apoptosis to this process using a model intestinal epithelial cell line, T84, and IFN-gamma and TNF-alpha. AJC structure/function was analyzed by confocal microscopy, biochemical analysis, and physiologic measurement of epithelial gate/fence function. Apoptosis was monitored by determining cytokeratin 18 cleavage and
caspase-3
activation. IFN-gamma induced time-dependent disruptions in epithelial gate function that were potentiated by coincubation with TNF-alpha. Tight junction fence function was somewhat disrupted. Cytokine treatment was associated with internalization of AJC transmembrane proteins, junction adhesion molecule 1, occludin, and claudin-1/4 with minimal effects on the cytoplasmic plaque protein zonula occludens 1. Detergent solubility profiles of junction adhesion molecule 1 and
E-cadherin
and their affiliation with "raft-like" membrane microdomains were modified by these cytokines. Inhibition of cytokine-induced apoptosis did not block induced permeability defects; further emphasizing their primary influence on the epithelial AJC structure and barrier function. Our findings for the first time clearly separate the proapoptotic effects of IFN-gamma and TNF-alpha from their abilities to disrupt barrier function.
...
PMID:Proinflammatory cytokines disrupt epithelial barrier function by apoptosis-independent mechanisms. 1463 32
Cisplatin is a commonly used antitumor agent in the treatment of various human cancers, with nephrotoxicity as a major side effect. Cisplatin causes the loss of cell-cell contacts of renal proximal tubular epithelial cells prior to the onset of apoptosis. We studied the involvement of protein kinase C in these events in the renal epithelial cell line LLC-PK1. Cisplatin caused apoptosis in LLC-PK1 cells, which was directly related to the activation of
caspase-3
and DNA fragmentation. Apoptosis was almost completely inhibited by the protein kinase C inhibitors bisindolylmaleimide (Bis) I and Go6983 [2-[1-(3-dimethylaminopropyl)-5-methoxyindol-3-yl]-3-(1H-indol-3-yl) maleimide], but not by Go6976 [12-(2-cyanoethyl)-6,7,12,13-tetrahydro-13-methyl-5-oxo-5H-indolo(2,3-a)pyrrolo(3,4-c)-carbazole]. Also, in primary cultured rat renal proximal tubular cells, inhibition of protein kinase C (PKC) inhibited apoptosis. Cisplatin also caused the early loss of cell-cell adhesions, which was associated with the altered localization of the adherens junction-associated protein beta-catenin in association with PKC-mediated phosphorylation of the actincapping protein adducin. These events preceded and were independent of caspase activation. beta-Catenin did not dissociate from
E-cadherin
. Cisplatin-induced loss of cell-cell contacts was associated with the increased formation of F-actin stress fibers, which was inhibited by Bis I and Go6983 as well as dominant-negative PKC-epsilon. Also, the loss of cell-cell adhesions by cisplatin was prevented by Bis I and Go6983. Activation of protein kinase C with phorbol esters promoted cisplatin-induced loss of cell-cell adhesions as well as apoptosis. In conclusion, the combined data fit a model whereby protein kinase C mediates the cisplatin-induced loss of cellular interactions. Such a loss of these interactions has a role in the onset of apoptosis.
...
PMID:Protein kinase C mediates cisplatin-induced loss of adherens junctions followed by apoptosis of renal proximal tubular epithelial cells. 1538 33
The RON (recepteur d'origine nantais) receptor belongs to the MET proto-oncogene family that is implicated in the oncogenesis of the gastrointestinal epithelium. The present study aimed to determine the role of RON in regulating epithelial phenotypes in response to transforming growth factor (TGF)-beta1. Expression and activation of RON in SV40-immortalized mouse intestinal epithelial MODE-K cells result in reduction of cellular sensitivities towards apoptotic signals elicited by TGF-beta1. This effect is dependent on RON expression and phosphorylation that inhibit the TGF-beta1-induced activation of
caspase-3
and truncation of BAD. Among cellular signaling components, the activation of MAP kinase is critical in the RON-mediated inhibitory effect. PD98059, a specific MAP kinase inhibitor, prevented RON-mediated anti-apoptotic activities. PD98059 also prevented the inhibitory effect of RON on TGF-beta1-induced cleavage of
caspase-3
and BAD. By protecting cells from apoptotic death, activated RON collaborates with TGF-beta1 in the induction of cell morphological changes with decreased
E-cadherin
expression and increased migration and morphogenesis. Thus, RON expression and activation modulate phenotypes of gastrointestinal epithelial cells in response to TGF-beta1 with reduced sensitivity to apoptosis and increased migration. These activities might represent a mechanism by which RON activation increases tumorigenic activities and facilitates the progression of transformed epithelial cells towards malignancy.
...
PMID:Activation of the RON receptor tyrosine kinase attenuates transforming growth factor-beta1-induced apoptotic death and promotes phenotypic changes in mouse intestinal epithelial cells. 1544 77
Although ischemia has been shown to disrupt cell adhesion, the underlying molecular mechanism is unknown. In these studies, we adapted a model of ischemia-reperfusion to normal rat kidney (NRK) cells, examined disruption of the cadherin/catenin complex, and identified a role for matrix metalloproteinases (MMPs) in ischemia-induced cleavage of cadherins. In NRK cells, ischemia was induced by applying a thin layer of PBS solution supplemented with calcium and magnesium and a layer of mineral oil, which restricts exposure to oxygen. NRK cells exhibited extracellular 80-kDa and intracellular 40-kDa
E-cadherin
fragments after 4 h of ischemia, and at 6 h the expression of full-length
E-cadherin
decreased. While no fragments of N-cadherin, alpha-catenin, and gamma-catenin were observed at any time point, the detectable levels of these proteins decreased during ischemia. Ischemia was detected by an increase in pimonidazole adducts, as well as an increase in glucose transporter-1 protein expression. Ischemia did not decrease cell number, but there was a decrease in ATP levels. In addition, there was no evidence of cleaved
caspase 3
or 9 during 6 h of ischemia. The MMP inhibitors GM-6001 and TAPI-O inhibited cleavage and/or loss of E- and N-cadherin protein expression. Tissue inhibitors of metalloproteinases (TIMP)-3 and to a lesser extent TIMP-2, but not TIMP-1, inhibit ischemic cleavage and/or loss of E- and N-cadherin. These results demonstrate that ischemia induces a selective metalloproteinase-dependent cleavage of
E-cadherin
and decrease in N-cadherin that are associated with a disruption of junctional contacts.
...
PMID:Ischemia-induced cleavage of cadherins in NRK cells: evidence for a role of metalloproteinases. 1576 36
Beta-catenin functions both as a regulator of cadherin-mediated cell-cell adhesion and a mediator of Wnt signaling. Recently,
caspase-3
-dependent cleavage of beta-catenin was demonstrated to occur during apoptosis. Here, we show that beta-catenin is proteolytically cleaved in G401 Wilms' tumor cells that were detached from the culture dish. Beta-catenin cleavage products of the same electrophoretic mobility were detected in G401 cells after induction of apoptosis with staurosporine and cell cycle arrest by aphidicolin. The detached cells show no sign of anoikis and approximately 90% of the floating cells were able to reattach to new dishes. Furthermore, beta-catenin was not cleaved in cells cultured on dishes coated with poly(2-hydroxyethylmethacrylate), which inhibits cellular attachment on the dishes, with approximately 90% of cells viable under these conditions. All beta-catenin cleavage products lost N-terminal and C-terminal regions and were unable to associate with alpha-catenin, which is responsible for actin filament binding and organization. However, they were still able to associate with
E-cadherin
. Aggregation assays revealed that the floating cells had weak aggregation compared with the attached cells. These results suggest that the cleavage of beta-catenin during cell detachment functions at least in part to remove the alpha-catenin-binding domain, thereby reducing cell adhesion activity.
...
PMID:Beta-catenin cleavage in non-apoptotic cells with reduced cell adhesion activity. 1587 Sep 2
Photodynamic treatment with different photosensitizers (PSs) can result in the specific induction of apoptosis in many cell types. It is commonly accepted that this apoptotic response depends on the mitochondrial accumulation of the PS. Accumulation in other cellular organelles, such as lysosomes or the Golgi complex, and subsequent photodamage resulting in an apoptotic process has been also described. However, the role played by cell adhesion in apoptosis induced in epithelial cells after photodynamic treatment is not well characterized. Here, we have used a murine keratinocyte line, showing a strong dependence on
E-cadherin
for cell-cell adhesion and survival, to analyze the relevance of this adhesion complex in the context of zinc(II)-phthalocyanine (ZnPc) photodynamic treatment. We report that under apoptotic conditions, ZnPc phototreatment induces a rapid disorganization of the
E-cadherin
mediated cell-cell adhesion, which largely preceded both the detachment of cells from the substrate, via beta-1 integrins and the induction of apoptotic mitochondrial markers. Therefore, the alteration in
E-cadherin
, alpha- and beta-catenins adhesion proteins preceded the release of cytochrome c (cyt c) from mitochondria to the cytosol and the activation of
caspase 3
. In addition, blocking
E-cadherin
function with a specific antibody (Decma-1) induced apoptosis in this cell system. These results strongly suggest that the
E-cadherin
adhesion complex could be the primary target of ZnPc phototreatment, and that loss of
E-cadherin
mediated cell adhesion after early photodamage triggers an apoptotic response.
...
PMID:Loss of E-cadherin mediated cell-cell adhesion as an early trigger of apoptosis induced by photodynamic treatment. 1588 Jun 54
FTY720, a derivative of fungus, has demonstrated dramatic anticancer effect in several malignancies recently. Our study evaluates the therapeutic potential of FTY720 in the treatment of androgen-independent prostate cancer using a human prostate cancer xenograft in nude mice. CWR22R, an androgen-independent human prostate tumor xenograft was inoculated into castrated nude mice and the animals were administrated with either normal saline or FTY720 (10 mg/kg) through intraperitoneal (i.p.) injection for 20 days. Body weight and tumor volume were recorded every 2 days, and serum prostate specific antigen (PSA) levels were also measured before and after the treatment. The effect of FTY720 on tumor cell proliferation was examined using antibodies against PCNA and Ki-67 by immunohistochemical staining, MTT assay and colony forming assay, whereas apoptotic effect of FTY720 was evaluated by TUNEL assay and immunostaining using antibodies against cleaved
caspase 3
and Bcl-2. In addition, the potential inhibitory effect of FTY720 on prostate cancer angiogenesis and metastasis was investigated by immunostaining of CD31, VEGF,
E-cadherin
and beta-catenin. Our results showed that FTY720 treatment led to suppression of CWR22R tumor growth without causing any detectable side effects in nude mice. The FTY720-induced tumor suppression was correlated with decreased serum PSA level as well as reduced proliferation rate, suppression of angiogenic factors, and restoration of
E-cadherin
and beta-catenin expression. In addition, the FTY720-treated tumors showed increased apoptosis rate demonstrated by increased TUNEL- and cleaved
caspase 3
-positive cells, and decreased Bcl-2 expression. Our results suggest a potential novel agent in the suppression of androgen-independent prostate cancer.
...
PMID:FTY720, a fungus metabolite, inhibits in vivo growth of androgen-independent prostate cancer. 1598 40
The aim of the current study was to evaluate the protein expression involved in the progression from dysplasia to invasive esophageal squamous cell carcinomas and to analyze the prognostic value of markers. Immunohistochemistry was performed for cell cycle regulators [p53, p21, p27, p16, cyclin D1, Rb], apoptosis-related proteins [Fas, Fas-L, FADD, TRAIL, DR4, DR5, caspase-8,
caspase-3
, bcl-2, Bax], tumor suppressor proteins [beta-catenin,
E-cadherin
, FHIT, Smad 4, VHL, PTEN, KAI-1], and oncoproteins [c-myc, COX-2, EGFR].
Caspase-3
, TRAIL, Fas-L, Fas, Smad 4, VHL,
E-cadherin
, and EGFR revealed significant differences between dysplasia and their corresponding invasive cancer portion in 25 cases. In a total of 118 cases of invasive cancer, proteins with frequent (> or = 60% of the cases) alterations were p53 (overexpression in 64% of SCCs), p27 (loss in 91%), p16 (loss in 81%), and FHIT (loss in 75%). Early clinical stage and bcl-2 immunopositivity were related to the survival rate of patients. In conclusion,
caspase-3
, TRAIL, Fas-L, Fas, Smad 4, VHL,
E-cadherin
, and EGFR may be involved in the progression from dysplasia to invasive esophageal SCCs. Clinical stage and bcl-2 are independent prognostic factors throughout the multivariate analysis.
...
PMID:Differential protein expression between esophageal squamous cell carcinoma and dysplasia, and prognostic significance of protein markers. 1613 47
To investigate the role of nuclear encoded genes in mitochondrial function during oocyte maturation and early embryogenesis we examined the expression pattern and function of the cytochrome oxidase (Cox) subunits, Cox5a, 5b, and 6b1 during oocyte maturation and early embryo development. Transcription of Cox5a, 5b, or 6b1 was observed in oocytes and during early development; their expression levels were abundant in mature oocytes (MII) and zygotes (1C), and lowest at the 2-cell stage (2C), gradually increasing from 4-cell to blastocyst stage. Immunocytochemical studies revealed that COX5A, 5B, or 6B1 proteins were expressed in all blastomeres of the blastocyst. Silencing of mRNA expression by RNA interference (siRNA) did not inhibit oocyte maturation or developmental events up to the morula and blastocyst stages, but disrupted mitochondrial distribution. Significantly higher apoptosis and lower cell numbers were observed in siRNA-treated blastocysts. Real time RT-PCR revealed that silencing of Cox5a, 5b, or 6b1 did not alter mRNA levels of Bcl-xL (Bcl2l1), but increased transcription levels of proapoptotic genes, Bax and
caspase 3
(Casp3). Furthermore, mRNA and protein levels of
E-cadherin
(CDH1) were decreased in siRNA microinjected blastocysts. These results suggest that gene expression of the Cox subunits, Cox5a, 5b, and 6b1 is not required for embryo developmental events up to the blastocyst stage. The loss of these genes leads to mitochondrial dysfunction that results in apoptosis of the blastocyst stage embryos.
...
PMID:Gene expression of cox5a, 5b, or 6b1 and their roles in preimplantation mouse embryos. 1629 27
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>