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)

Identification and characterization of p53 target genes would lead to a better understanding of p53 functions and p53-mediated signaling pathways. Two putative p53 binding sites were identified in the promoter of a gene encoding PTGF-beta, a type beta transforming growth factor (TGF-beta) superfamily member. Gel shift assay showed that p53 bound to both sites. Luciferase-coupled transactivation assay revealed that the gene promoter was activated in a p53 dose- as well as p53 binding site-dependent manner by wild-type p53 but not by several p53 mutants. The p53 binding and transactivation of the PTGF-beta promoter was enhanced by etoposide, a p53 activator, and was largely blocked by a dominant negative p53 mutant. Furthermore, expression of endogenous PTGF-beta was remarkably induced by etoposide in p53-positive, but not in p53-negative, cell lines. Finally, the conditioned medium collected from PTGF-beta-overexpressing cells, but not from the control cells, suppressed tumor cell growth. Growth suppression was not, however, seen in cells that lack functional TGF-beta receptors or Smad4, suggesting that PTGF-beta acts through the TGF-beta signaling pathway. Thus, PTGF-beta, a secretory protein, is a p53 target that could mediate p53-induced growth suppression in autocrinal as well as paracrinal fashions. The finding made a vertical connection between p53 and TGF-beta signaling pathways in controlling cell growth and implied a potential important role of p53 in inflammation regulation via PTGF-beta.
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PMID:PTGF-beta, a type beta transforming growth factor (TGF-beta) superfamily member, is a p53 target gene that inhibits tumor cell growth via TGF-beta signaling pathway. 1061 79

The transcription regulatory function of p53 was analyzed by using two inducible p53 systems in the human lung cancer cell line H1299. cDNA probes derived from RNA harvested 12 h after p53 induction were used to probe filters containing cDNA arrays. Over 20 genes were found to be significantly induced or suppressed by p53. The induced genes can be classified mainly as cell cycle inhibitors like p21waf, GADD45, apoptosis-related genes like Fas/APO1 and PIG3 or DNA repair genes like DDB2, DNA ligase and G/T mismatch DNA glycosylase. The suppressed genes include mainly cell cycle regulators like cyclin B1, cyclin H and kinases like c-abl, CLK1 and others. The most notable induced gene was MIC-1, encoding a TGF-beta-related secretory protein, suggesting a potential paracrine component for p53 growth suppression.
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PMID:Profile of gene expression regulated by induced p53: connection to the TGF-beta family. 1072 49

Apoptosis (programmed cell death) is a genetically programmed active cell death process for maintaining homeostasis under physiological conditions and for responding to various stimuli. Many human diseases have been associated with either increased apoptosis (such as AIDS and neurodegenerative disorders) or decreased apoptosis (such as cancer and autoimmune disorders). In an attempt to understand apoptosis signaling pathway and genes associated with apoptosis, we established two cell model systems on which apoptosis is induced either by DNA damaging agent, etoposide or by redox agent, 1,10-phenanthroline (OP). DNA chip profiling or mRNA differential display (DD) was utilized to identify genes responsive to apoptosis induced by these two agents. In etoposide model with chip hybridization, we defined signaling pathways that mediate apoptosis in p53 dependent manner (through activation of p53 target genes such as Waf-1/p21, PCNA, GPX, S100A2 and PTGF-beta) as well as in p53-independent manner (through activation of ODC and TGF-beta receptor, among others). In OP model with DD screening, we cloned and characterized two genes: glutathione synthetase, encoding an enzyme involved in glutathione synthesis and Sensitive to Apoptosis Gene (SAG), a novel evolutionarily conserved gene encoding a zinc RING finger protein. Both genes appear to protect cells from apoptosis induced by redox agents. Further characterization of SAG revealed that it is a growth essential gene in yeast and belongs to a newly identified gene family that promotes protein ubiquitination and degradation. Through this activity, SAG regulates cell cycle progression and many other key biological processes. Thus, SAG could be a valid drug target for anti-cancer and anti-inflammation therapies.
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PMID:Identification and characterization of genes responsive to apoptosis: application of DNA chip technology and mRNA differential display. 1100 51

Dietary phenolic substances including resveratrol, a stillbene compound, are found in several fruits and vegetables, and these compounds have been reported to have anti-oxidant, anti-inflammatory and antitumorigenic activities. However, the molecular mechanisms underlying the antitumorigenic or chemopreventive activities of these compounds remain largely unknown. The expression of NAG-1 [non-steroidal anti-inflammatory (NSAID) drug-activated gene-1], a member of the transforming growth factor-beta (TGF-beta) superfamily, has been shown to be associated with pro-apoptotic and antitumorigenic activities. Here, we have demonstrated that resveratrol induces NAG-1 expression and apoptosis in a concentration-dependent manner. Resveratrol increases the expression of p53, tumor suppressor protein, prior to NAG-1 induction, indicating that NAG-1 expression by resveratrol is mediated by p53 expression. We also show that the p53 binding sites within the promoter region of NAG-1 play a pivotal role to control NAG-1 expression by resveratrol. Derivatives of resveratrol were examined for NAG-1 induction, and the data suggest that resveratrol-induced NAG-1 and p53 induction is not dependent on its anti-oxidant activity. The data may provide linkage between p53, NAG-1 and resveratrol, and in part, a new clue to the molecular mechanism of the antitumorigenic activity of natural polyphenolic compounds.
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PMID:Resveratrol enhances the expression of non-steroidal anti-inflammatory drug-activated gene (NAG-1) by increasing the expression of p53. 1189 57

Garlic is appealing as an anti-carcinogenic agent due to its ability to induce apoptosis in vitro and inhibit the formation and growth of tumors in animals in vivo. Diallyl disulfide (DADS) is a constituent of garlic that suppresses neoplastic cell growth and induces apoptosis. We examined the effects of DADS on various cancer cell lines to better understand its effect on apoptosis and apoptosis-related genes. The nonsteroidal anti-inflammatory drug (NSAID)-activated gene (NAG-1) has proapoptotic and antitumorigenic activities and is upregulated by anticancer agents such as NSAIDs. In this study, human colorectal HCT-116 (wild-type p53), HCT-15 (p53 mutant) and human prostate PC-3 (p53 mutant) cells were exposed to DADS. DADS inhibited cell proliferation in all cell lines albeit to a lesser extent in HCT-15 and PC-3 cells at 11.5 and 23 micromol/L. In HCT-116 cells, DADS induced p53 and NAG-1 in a dose-dependent manner and the induction of p53 preceded that of NAG-1. In HCT-116 cells, NAG-1 protein expression was increased 2.4-fold +/- 0.6 at 4.6 micromol/L and 6.1-fold +/- 1.7 at 23 micromol/L DADS, whereas p53 was induced 1.5-fold +/- 0.1 and 2.3-fold +/- 0.4. DADS did not induce NAG-1 or p53 in p53 mutant cell lines; however, NAG-1 expression was induced by sulindac sulfide. HCT-116 cells treated with 4.6 and 23 micromol/L DADS resulted in a 1.9- and 2.9-fold increase in apoptosis, respectively. In contrast, 23 micromol/L DADS induced apoptosis only 1.8-fold in HCT-15 cells and not at all in PC-3 cells. Thus, DADS-induced apoptosis and NAG-1 protein expression appear to occur via p53.
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PMID:Diallyl disulfide (DADS) induces the antitumorigenic NSAID-activated gene (NAG-1) by a p53-dependent mechanism in human colorectal HCT 116 cells. 1192 76

Human astrocytic brain tumors select for mutations in the p53 tumor suppressor gene early in malignant progression. p53 is activated upon various kinds of cellular stress leading to apoptosis or cell cycle arrest, but is also implicated in complex biological processes such as inhibition of angiogenesis and metastasis. In an effort to shed light on consequences mediated by p53 inactivation in gliomas, we established the Tet-On system for p53 in the LN-Z308 glioblastoma cell line. The macrophage inhibitory cytokine-1 (MIC-1) gene was identified as a most prominent p53 target gene upon gene expression profiling. Oxygen deprivation, an important cellular stress, revealed MIC-1 as an anoxia responsive gene in glioblastoma cell lines. MIC-1 up-regulation by anoxia is mediated through an alternative, p53 and hypoxia inducible factor 1 (HIF-1) independent pathway. Furthermore, ectopic expression of MIC-1 in LN-Z308 cell line completely abolished its inherent tumorigenicity in nude mice, while proliferation in vitro was not affected. In the present experimental model MIC-1 may exert its anti-tumorigenic properties via a paracrine mechanism mediated by host cells in vivo. Taken together, these data suggest that MIC-1 is an important downstream mediator of p53 function, while acting itself as an intercessor of cellular stress signaling and exerting anti-tumorigenic activities.
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PMID:Anoxia induces macrophage inhibitory cytokine-1 (MIC-1) in glioblastoma cells independently of p53 and HIF-1. 1208 8

In this study, we analyze the effect of several retinoids on the expression of nonsteroidal anti-inflammatory drug-activated gene (NAG-1) in normal human tracheobronchial epithelial (HTBE) cells and several lung carcinoma cell lines. The retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (AHPN) greatly enhances the expression of NAG-1 mRNA and protein in a time- and dose-dependent manner in human lung adenocarcinoma H460 cells and several other carcinoma cell lines. This induction was specific for AHPN because retinoic acid, a retinoic acid receptor-, and a retinoid X receptor pan-agonist were unable to induce NAG-1, suggesting that this induction is not mediated through activation of retinoid receptors. Although NAG-1 is a p53-responsive gene, AHPN-induced NAG-1 expression does not require p53. The induction of NAG-1 expression by AHPN is caused at least in part by an 8-fold increase in the stability of NAG-1 mRNA. In contrast to carcinoma cells, NAG-1 expression is effectively induced by retinoic acid and the RAR-selective pan-agonist in normal HTBE cells and accompanies the inhibition of squamous differentiation and the initiation of normal differentiation. In vivo, NAG-1 expression was observed in the normal tracheobronchial epithelium, whereas no expression was found in either squamous metaplastic tracheal epithelium or in sections of human lung tumors. Our results suggest that the induction of NAG-1 expression by retinoids in normal HTBE and lung carcinoma cells is regulated by distinct mechanisms and is associated with different biological processes. The linkage between AHPN treatment and NAG-1 expression revealed in this study provides a new mechanism for the antitumorigenic activity of AHPN.
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PMID:Differential regulation of nonsteroidal anti-inflammatory drug-activated gene in normal human tracheobronchial epithelial and lung carcinoma cells by retinoids. 1260 62

A candidate antitumor agent, 2-(4-amino-3-methylphenyl)-5-fluorobenzothiazole (5F-203), was empirically discovered through the National Cancer Institute's Anticancer Drug Screen from a unique growth inhibitory-response profile, indicating a novel mechanism of action. 5F-203 activates the CYP1 family of cytochrome P450, involving aryl hydrocarbon receptor translocation into the nucleus. To characterize more completely the pathways involved in 5F-203 toxicity, cDNA microarrays were used to determine gene expression changes in MCF-7, a 5F-203-sensitive breast cancer cell line, after treatment with 1 microM 5F-203. The mRNA expression of CYP1A1 and CYP1B1 were both increased approximately 20-fold after 24 h, but less after 6 h of treatment, confirming previous results. However, the most pronounced drug-induced change was in the PLAB gene, encoding one of the bone morphogenic proteins in the transforming growth factor-beta (TGF-beta) superfamily. Other induced gene expressions included the apoptosis-initiating receptor TNFRSF6 (CD95/FAS), the DNA-damage response genes CDKN1A (p21/Cip1), p53-induced gene-3, and DNA binding protein 2. In contrast, the transcription factor c-Myc showed reduced expression. Western blot analysis also showed induction of p53 protein expression in response to 5F-203 treatment. In contrast to the MCF-7 data, MDA-MB-435, a cancer cell line resistant to 5F-203, showed no change in expression of any of these genes or the p53 protein under the same conditions of 5F-203 treatment. These data are consistent with the idea that CYP1A1 and CYP1B1 activation leads to 5F-203 toxicity through DNA damage-induced apoptosis, as well as signaling through a variant member of the TGF-beta superfamily.
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PMID:Genotoxic profiling of MCF-7 breast cancer cell line elucidates gene expression modifications underlying toxicity of the anticancer drug 2-(4-amino-3-methylphenyl)-5-fluorobenzothiazole. 1260 87

The p53 tumor suppressor protein plays a key function in the cellular response to stress by activating a subset of genes responsible for cell cycle arrest and apoptosis. Activation of the p53 pathway in tumor cells has been proposed as a novel approach to cancer therapy and substantial efforts have been dedicated to the discovery of pharmacological p53 activators. Here, we show that the transforming growth factor-beta superfamily cytokine, macrophage inhibitory cytokine-1 (MIC-1), can serve as a secreted biomarker for activation of p53 in both cellular and xenograft models of human cancer. Using doxorubicin treatment in the HCT116 colon cancer cell line, we have shown that MIC-1 secretion into culture media is correlated with p53 pathway activation as measured by the up-regulation of its downstream transcriptional target p21. When transplanted into nude mice, HCT116 cells continued to secret human MIC-1 and mouse plasma levels correlated well with tumor volume. Treatment of these animals with a single dose of doxorubicin led to activation of the p53 pathway and a nearly 4-fold elevation of the plasma MIC-1 level, which was paralleled by p21 induction in the tumor xenografts. Estimation of MIC-1 concentration, both in vivo and in vitro, represents a novel tool for the study of p53 pathway and development of p53-activating therapeutics.
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PMID:Macrophage inhibitory cytokine-1: a novel biomarker for p53 pathway activation. 1457 67

There is persuasive epidemiological and experimental evidence that dietary polyphenolic plant-derived compounds have anticancer activity. Many laboratories, including ours, have reported such an effect in cancers of the gastrointestinal tract, lung, skin, prostate and breast. The catechins are a group of polyphenols found in green tea, which is one of the most commonly consumed beverages in the world. While the preponderance of the data strongly indicates significant antitumorigenic benefits from the green tea catechins, the potential molecular mechanisms involved remain obscure. We found that green tea components induce apoptosis via a TGF-beta superfamily protein, NAG-1 (Non-steroidal anti-inflammatory drug Activated Gene). In this report, we show that ECG is the strongest NAG-1 inducer among the tested catechins and that treatment of HCT-116 cells results in an increasing G(1) sub-population, and cleavage of poly (ADP-ribose) polymerase (PARP), consistent with apoptosis. In contrast, other catechins do not significantly induce NAG-1 expression, PARP cleavage or morphological changes at up to a 50-microM concentration. Furthermore, we provide evidence that ECG induces the ATF3 transcription factor, followed by NAG-1 induction at the transcriptional level in a p53-independent manner. The data generated by this study will help elucidate mechanisms of action for components in green tea and this information may lead to the design of more effective anticancer agents and informed clinical trials.
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PMID:Epicatechin gallate-induced expression of NAG-1 is associated with growth inhibition and apoptosis in colon cancer cells. 1530 87


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