Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors immunohistochemically studied the expression of the estrogen receptor (ER), 27-kD heat shock protein (HSP27) and pS2 in 118 invasive primary human breast cancers. Positive nuclear staining of the ER was detected in 64% of the cases and was closely correlated with the biochemical assay (p < 0.0001). ER-positive tumors were significantly decreased with tumor size and stage (p < 0.001 each), but not with lymph node status. Positivity of the ER was correlated with the cytoplasmic expression of HSP27 (p < 0.005), pS2 (not significant) and HSP70 (not significant). ER negativity was significantly correlated with the expression of p53, epidermal growth factor receptor (EGFR) and c-erbB-2 (p < 0.05 each). Thus, it was concluded that ER-positive breast carcinomas, relatively small in size, preferentially expressed HSP27, HSP70 and pS2 and that ER-negative tumors, relatively large in size, were predisposed to express p53, EGFR and c-erbB-2.
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PMID:Immunohistochemical detection of estrogen receptor in invasive human breast cancer: correlation with heat shock proteins, pS2 and oncogene products. 763 53

Polyomavirus large T-antigen transgenic mice develop cardiac hypertrophy characterized by an increase in atrial natriuretic factor and beta-myosin heavy chain isoform expression. The aim of this study was to examine changes in proto-oncogene expression in hypertrophied hearts from the transgenic mice. Expression of early growth response-1 (Egr-1) mRNA was detected in hearts from all 15 transgenic mice, but was not detectable in 13 control mice. Reverse transcriptase-polymerase chain reaction experiments using Egr-1-specific primers confirmed the increase in Egr-1 mRNA in enlarged hearts from the transgenic mice. Expression of c-jun, junD and Ha-ras mRNAs was increased in the transgenic hearts 3, 17 and 2.8-fold respectively. Western blots showed an increase in c-myc, c-jun and ras protein in hypertrophied transgenic hearts. Immunofluorescence analyses confirmed an increase in Egr-1 and c-jun protein in transgenic cardiomyocytes. Proliferating cell nuclear antigen, Ki-ras and HSP 90 mRNAs were decreased 22, 2.7 and 3-fold, respectively in the transgenic hearts. Not altered in most hypertrophied hearts was expression of c-fos, junB, p53, c-neu, c-myc, HSP70, HSP27, TGF-beta or IGF 1 mRNAs. Proto-oncogene and growth factor gene expression in hypertrophy induced by PVLT expression is modulated with some proto-oncogenes increased and others decreased in expression.
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PMID:Molecular remodelling in hypertrophied hearts from polyomavirus large T-antigen transgenic mice. 875 Nov 59

A case of carcinosarcoma composed of both adenocarcinoma and sarcomatous elements in the non-trigone region of the urinary bladder is presented. The epithelial element was a well to poorly differentiated adenocarcinoma with focal squamous metaplasia. The sarcomatous elements disclosed spindle cell sarcoma with focal epithelioid pattern and myxoid change in the stroma, together with chondrosarcomatous and rhabdomyosarcomatous elements. By immunohistochemical examination, not only the carcinoma element but also the sarcomatous elements showed a positive immunoreaction for cytokeratin (CK), epithelial membrane antigen (EMA) and carcinoembryonic antigen. Some population of sarcomatous elements expressed smooth muscle actin and muscle specific actin (MSA) and a limited portion of epithelioid area showed a positive immunoreaction for desmin, MSA and myoglobin, indicating leiomyosarcomatous and rhabdomyosarcomatous differentiation, respectively. Unexpectedly, tumor cells in the chondrosarcomatous element revealed a simultaneous positivity of CK and EMA as well as S-100 protein. Both epithelial and sarcomatous elements showed an intensive positive immunoreaction for p53 and heat shock protein (HSP) 70. However, HSP27 and HSP60 were detected in most epithelial elements and only in a small number of tumor cells in the sarcomatous area. These findings indicate that sarcomatous elements, including heterologous elements, may derive from epithelial elements with partial or complete loss of epithelial features, and different factors other than p53 and HSP70 may associate with the morphological alteration of carcinoma.
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PMID:Carcinosarcoma of the urinary bladder: expression of epithelial markers and different expression of heat shock proteins between epithelial and sarcomatous elements. 908 35

Twenty-four specimens of squamous cell carcinoma of the tongue were immunostained for heat shock proteins (HSPs) to reveal differences in stainability among normal epithelium, dysplasia and carcinoma and to clarify the prognostic significance of HSPs in comparison with survival period, clinical stage, lymph node metastasis, histological grade, and p53 immunostaining. Normal epithelium was positively stained in the suprabasal layer for HSP60 and HSP70, but was negative for HSP27 and HSP90. Dysplastic lesions were positive for HSP27, HSP70 and HSP90, but stained variously for HSP60. In squamous cell carcinoma, the cytoplasm of suprabasal tumor cells was often positive for HSP27 and HSP90 (18/24, 17/24, respectively). Although HSP immunohistochemistry has revealed changes in HSP expression during tumorigenesis of squamous epithelium of the tongue, there was no correlation between HSP staining and survival period, stage, lymph node metastasis, histological grade or p53 immunostaining.
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PMID:Expression of heat shock proteins in squamous cell carcinoma of the tongue: an immunohistochemical study. 946 30

Cyclosporin A is a widely used immunosuppressive drug having toxic side effects, in particular on kidneys and liver, as a result of its action on different molecular targets. Here we demonstrate that low doses of CsA are able to induce the expression of the heat shock protein HSP27 and its hyperphosphorylation. It also activates the two heat shock transcription factors, HSF1 and HSF2. Since these factors have been shown to be activated by proteasome inhibition, we tested the hypothesis that the inhibitory action of CsA on the proteasome might be responsible for the activation of HSFs and the subsequent expression of HSP27. The increase in multiubiquitinated proteins as well as the stabilization of p53 following CsA addition argues in favor of this hypothesis. The kidney BSC-1 cells are highly responsive to the addition of CsA: the possible link between HSP27 induction and hyperphosphorylation and nephrotoxicity is discussed.
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PMID:Cyclosporin A induces an atypical heat shock response. 1070 76

The prognosis of osteosarcoma has been improved by chemotherapy. Heat shock proteins (HSPs) assist in folding proteins at posttranslation and degeneration under stress. We investigated the effect of HSPs on survival in osteosarcoma. Conventional osteosarcomas of the extremities from 70 patients aged 30 years or younger were used. Preoperational chemotherapy was performed in all cases. Tissues at surgery and biopsy were immunohistochemically stained with anti-HSP27, HSP47, HSP60, HSP70, HSP90alpha, HSP90beta, and p53 antibodies. We classified the cases in which more than 10% of tumor cells were positive into the overexpressing group. Overall survival was compared between the groups either overexpressing HSPs or not using Wilcoxon's test and Cox's proportional hazard model. The overexpression rate at biopsy was 22% (HSP27), 88% (HSP47), 66% (HSP60), 48% (HSP70(, 47% (HSP90alpha), 31% (HSP90beta), and 17% (p53), respectively. The rate at surgery was 33% (HSP27), 94% (HSP47), 60% (HSP60), 49% (HSP70), 28% (HSP90alpha), 40% (HSP90beta), and 17% (p53), respectively. HSP27 and p53 overexpression at biopsy had a negative prognostic value. HSP27 showed the strongest negative prognostic value in osteosarcoma. It is therefore important to investigate further its function in cellular regulation and drug resistance.
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PMID:Expression of heat shock proteins in osteosarcoma and its relationship to prognosis. 1108 53

The present study was undertaken to determine the expression pattern of the hsp70 and the hsp27 genes in 106 cases of non-small cell lung carcinoma (NSCLC). We have shown that in the majority of cases (95/106) the HSP70 immunoreactivity was localized both in the cytoplasm and the nuclei. We also observed an enhanced nuclear immunoreaction for HSP70 in dysplastic lesions and in stage I tumors. In the case of the HSP27 we found a positive cytoplasmic immunostaining in 70% of cases, with the highest score in squamous cell carcinoma (SCC). We noted a positive correlation between the expression level of HSP27 and HSP70. There was a correlation between Ki-67 proliferation index and nuclear HSP70 staining, but not for HSP27. No association between the HSPs and the expression of pRb p16 and p21WAF1/CIP1 and p53 was found as studied previously. An interesting and statistically significant relationship was found between the expression of cyclin D1 and high intensity of HSP27 and HSP70 immunostaining. The relation of our results concerning the expression pattern of the HSP70 and HSP27 in NSCLC to those obtained by others for different types of primary tumors is discussed.
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PMID:Expression of heat shock proteins HSP70 and HSP27 in primary non-small cell lung carcinomas. An immunohistochemical study. 1139 34

Post-translational modifications (PTMs) are known to regulate biological processes by controlling protein function. The effect of a PTM on protein function depends critically on the position and the number of modifications. While there are convenient methods available to qualitatively examine modifications like phosphorylation, glycosylation, acetylation and methylation, methods available for their quantitative assessment are cumbersome. We have developed a new tool that allows quantitation of the number of phosphorylation events in proteins with ease. The "ProteoMod" tool depends on shifts in the isoelectric points of proteins upon post-translational change. The extent of shift exhibited upon phosphorylation is algorithmically converted into the number of phosphorylations conferred. The validity of ProteoMod was confirmed by examining proteins with previously known number of phosphorylations. The list of proteins examined included HSP27, HSP70 and tumor suppressor p53. The approach can also be applied to estimate modifications like acetylation, methylation and sialylation in proteins. We analyzed shifts in isoelectric points due to sialylation events in N-glycoproteins. Using influenza hemagglutinin we show that shifts in isoelectric points correlate with intracellular distribution of this model membrane protein. In addition to extending the application of two dimensional gel electrophoresis to quantitate modifications, our study also highlights its potential use in cell biology.
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PMID:ProteoMod: A new tool to quantitate protein post-translational modifications. 1517 36

Cellular senescence can result from short, dysfunctional telomeres, oxidative stress, or oncogene expression, and may contribute to aging. To investigate the role of cellular senescence in aging it is necessary to define the time-dependent molecular events by which it is characterized. Here we investigated changes in levels of key proteins involved in cell cycle regulation, DNA replication, and stress resistance in senescing human fibroblasts following oxidative stress. An immediate response in stressed cells was dephosphorylation of retinoblastoma (Rb) and cessation of DNA synthesis. This was followed by sequential induction of p53, p21, and p16. Increase in hypophosphorylated Rb and induction of p53 and p21 by a single stress treatment was transient, whereas sustained induction or dephosphorylation were achieved by a second stress. Down-regulation of the critical DNA replication initiation factor Cdc6 occurred early after stress concurring with p53 induction, and was followed by a decrease in Mcm2 levels. A late event in the stress-induced molecular sequence was the induction of SOD1, catalase, and HSP27 coinciding with development of the fully senescent phenotype. Our data suggest that loss of proliferative capacity in oxidatively stressed cells is a multistep process regulated by time-dependent molecular events that may play differential roles in induction and maintenance of cellular senescence.
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PMID:Loss of proliferative capacity and induction of senescence in oxidatively stressed human fibroblasts. 1537 61

We have previously demonstrated that c-Myc impairs p53-mediated apoptosis in K562 human leukemia cells, which lack ARF. To investigate the mechanisms by which c-Myc protects from p53-mediated apoptosis, we used K562 cells that conditionally express c-Myc and harbor a temperature-sensitive allele of p53. Gene expression profiles of cells expressing wild-type conformation p53 in the presence of either uninduced or induced c-Myc were analysed by cDNA microarrays. The results show that multiple p53 target genes are downregulated when c-Myc is present, including p21WAF1, MDM2, PERP, NOXA, GADD45, DDB2, PIR121 and p53R2. Also, a number of genes that are upregulated by c-Myc in cells expressing wild-type conformation p53 encode chaperones related to cell death protection as HSP105, HSP90 and HSP27. Both downregulation of p53 target genes and upregulation of chaperones could explain the inhibition of apoptosis observed in K562 cells with ectopic c-Myc. Myc-mediated impairment of p53 transactivation was not restricted to K562 cells, but it was reproduced in a panel of human cancer cell lines derived from different tissues. Our data suggest that elevated levels of Myc counteract p53 activity in human tumor cells that lack ARF. This mechanism could contribute to explain the c-Myc deregulation frequently found in cancer.
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PMID:Inhibitory effect of c-Myc on p53-induced apoptosis in leukemia cells. Microarray analysis reveals defective induction of p53 target genes and upregulation of chaperone genes. 1585 24


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