Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.22 (cdc2)
 8,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Resveratrol (3,5,4'-trihydroxystilbene) is a naturally occurring phytoalexin, found in grapes and wine, which has been reported to exert a variety of important pharmacological effects. We have investigated the activity of resveratrol on proliferation and differentiation of the promyelocitic cell line HL-60. A concentration as low as 30 microM causes a complete arrest of proliferation and a rapid induction of differentiation towards a myelo-monocytic phenotype. Analyses by flow cytometry showed the absence of the G2/M peak and the accumulation of cells in G1 and S phases. Moreover, at the concentrations employed, a very low amount of apoptotic cells was evidenced. A detailed biochemical analysis demonstrated that the G1 phase of the cell division cycle engine was completely unmodified by resveratrol addition, thus indicating that the G1 --> S transition occurs normally. Conversely, after only 24 h treatment, a significant increase of cyclins A and E could be observed along with the accumulation of cdc2 in the inactive phosphorylated form. These data demonstrate that resveratrol causes a complete and reversible cell cycle arrest at the S phase checkpoint.
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PMID:Resveratrol arrests the cell division cycle at S/G2 phase transition. 973 30

Resveratrol (trans-3,4',5,-trihydroxystilbene), a phytoalexin found in grapes, nuts, fruits, and red wine, is a potent antioxidant with cancer-preventive properties. The mechanism by which resveratrol imparts cancer chemopreventive effects is not clearly defined. Here, we demonstrate that resveratrol, via modulations in cyclin-dependent kinase (cdk) inhibitor-cyclin-cdk machinery, results in a G(1)-phase arrest of the cell cycle followed by apoptosis of human epidermoid carcinoma (A431) cells. Resveratrol treatment (1-50 microM for 24 h) of A431 cells resulted in a dose-dependent (a) inhibition of cell growth as shown by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, (b) G(1)-phase arrest of the cell cycle as shown by DNA cell cycle analysis, and (c) induction of apoptosis as assessed by ELISA. The immunoblot analysis revealed that resveratrol treatment causes a dose- and time-dependent (a) induction of WAF1/p21; (b) decrease in the protein expressions of cyclin D1, cyclin D2, and cyclin E; and (c) decrease in the protein expressions of cdk2, cdk4, and cdk6. Resveratrol treatment was also found to result in a dose- and time-dependent decrease in kinase activities associated with all of the cdks examined. Taken together, our study suggests that resveratrol treatment of the cells causes an induction of WAF1/p21 that inhibits cyclin D1/D2-cdk6, cyclin D1/D2-cdk4, and cyclin E-cdk2 complexes, thereby imposing an artificial checkpoint at the G(1)-->S transition of the cell cycle. This series of events results in a G(1)-phase arrest of the cell cycle, which is an irreversible process that ultimately results in the apoptotic death of cancer cells. To our knowledge, this is the first systematic study showing the involvement of each component of cdk inhibitor-cyclin-cdk machinery during cell cycle arrest and apoptosis of cancer cells by resveratrol.
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PMID:Resveratrol causes WAF-1/p21-mediated G(1)-phase arrest of cell cycle and induction of apoptosis in human epidermoid carcinoma A431 cells. 1135 Sep 19

Resveratrol is a naturally occurring polyphenol with cancer chemopreventive properties. The objective of the current study was to investigate the effect of resveratrol on the human colonic adenocarcinoma cell line Caco-2. The compound inhibited cell growth and proliferation of Caco-2 cells in a dose-dependent manner (12.5-200 micromol/L) as assessed by crystal violet assay, [(3)H]thymidine and [(14)C]leucine incorporation. Furthermore, apoptosis was determined by measuring caspase-3 activity, which increased significantly after 24 and 48 h of treatment with 200 micromol/L resveratrol. Perturbed cell cycle progression from the S to G2 phase was observed for concentrations up to 50 micromol/L, whereas higher concentrations led to reversal of the S phase arrest. These effects were specific for resveratrol; they were not observed after incubation with the stilbene analogs stilbenemethanol and rhapontin. Levels of cyclin D1 and cyclin-dependent kinase (cdk) 4 proteins were decreased, as revealed by immunoblotting. In addition, resveratrol enhanced the expression of cyclin E and cyclin A. The protein levels of cdk2, cdk6 and proliferating cell nuclear antigen were unaffected. Similar results were obtained for the colon carcinoma cell line HCT-116, indicating that cell cycle inhibition by resveratrol is independent of cyclooxygenase inhibition. The phosphorylation state of the retinoblastoma protein in Caco-2 cells was shifted from hyperphosphorylated to hypophosphorylated at 200 micromol/L, which may account for reversal of the S phase block at concentrations exceeding 50 micromol/L. These findings suggest that resveratrol exerts chemopreventive effects on colonic cancer cells by inhibition of the cell cycle.
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PMID:Downregulation of the cyclin D1/Cdk4 complex occurs during resveratrol-induced cell cycle arrest in colon cancer cell lines. 1148 17

Resveratrol (trans-3,4',5-trihydroxystilbene), a polyphenolic phytoalexin found in grapes, nuts, many other fruits, and red wine, is a potent antioxidant with anti-inflammatory and cancer-preventive properties. The mechanism(s) by which resveratrol imparts cancer chemopreventive effects has not been clearly defined. Earlier, we have shown that resveratrol treatment results in an induction of the cyclin kinase inhibitor WAF1/CIP1/p21 which, by inhibiting cyclin (E, D1, and D2) and cyclin-dependent kinases (cdk2, cdk4, and cdk6), results in a G0/G1-phase arrest followed by apoptosis of A431 human epidermoid carcinoma cells (Ahmad et al., Clin. Cancer Res. 7, 1466-1473, 2001). Retinoblastoma (pRb) and the E2F family of transcription factors are important proteins, which regulate the progression of the cell cycle at and near the G1-->S phase transition. Here we provide evidence for the involvement of the pRb-E2F/DP pathway as an important contributor of resveratrol-mediated cell cycle arrest and apoptosis. Immunoblot analysis demonstrated that resveratrol treatment of A431 cells results in a dose- as well as time-dependent decrease in the hyperphosphorylated form of pRb with a relative increase in hypophosphorylated pRb. This response was accompanied by downregulation of protein expression of all five E2F ( 1 - 5 ) family members of transcription factors studied and their heterodimeric partners DP1 and DP2. This suggests that resveratrol causes a downregulation of hyperphosphorylated pRb protein with a relative increase in hypophosphorylated pRb that, in turn, compromises with the availability of free E2F. We suggest that this series of events results in a stoppage of the cell cycle progression at the G1-->S phase transition thereby leading to a G0/G1 arrest and subsequent apoptotic cell death. To our knowledge, this is the first study showing the involvement of the pRb-E2F/DP pathway as a mechanism of the cancer-chemopreventive effects of resveratrol.
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PMID:Involvement of the retinoblastoma (pRb)-E2F/DP pathway during antiproliferative effects of resveratrol in human epidermoid carcinoma (A431) cells. 1167 82

Resveratrol has an apoptotic effect on a variety of cancer cells. Changes in cell cycle regulatory processes contributing to the antiproliferative effect of resveratrol remain largely unknown. Our studies revealed that, in androgen-sensitive LNCaP cells, the effect of resveratrol on DNA synthesis varied dramatically depending on the concentration and the duration of treatment. In 1-h-treated cells, resveratrol showed only an inhibitory effect on DNA synthesis, which increased with increasing concentration (IC50 = 20 microM). However, when treatment duration was extended to 24 h, we observed a dual effect of resveratrol on DNA synthesis. At 5 to 10 microM it caused a 2- to 3-fold increase in DNA synthesis, and at > or =15 microM, it inhibited DNA synthesis. The increase in DNA synthesis was seen only in LNCaP cells, but not in androgen-independent DU145 prostate cancer cells or in NIH3T3 fibroblast cells. The resveratrol-induced increase in DNA synthesis was associated with enrichment of LNCaP cells in S phase, and a concurrent decrease in nuclear p21Cipl and p27Kip1 levels. Furthermore, consistent with the entry of LNCaP cells into S phase, there was a dramatic increase in nuclear Cdk2 activity associated with both cyclin A and cyclin E. Taken together, our observations indicate that LNCaP cells, treated with resveratrol, are induced to enter into S phase, but subsequent progression through S phase is limited by the inhibitory effect of resveratrol on DNA synthesis, particularly at concentrations above 15 microM. Therefore, this unique ability of resveratrol to exert opposing effects on two important processes in cell cycle progression, induction of S phase and inhibition of DNA synthesis, may be responsible for its apoptotic and antiproliferative effects.
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PMID:Resveratrol induces prostate cancer cell entry into s phase and inhibits DNA synthesis. 1198 Jun 38

Resveratrol is a natural polyphenolic compound produced by a number of plants and found in high amount in peanuts, seeds, grapes or berries as source of human nutrition. Epidemiological studies strongly suggest that resveratrol may act as a cancer chemopreventive compound. The mechanism by which resveratrol inhibits cell proliferation was studied in human colorectal tumor SW480 cell line. The results show that resveratrol strongly inhibits cell proliferation at the micromolar range in a time- and dose-dependent manner. Resveratrol appears to block the cell cycle at the transition --> G2/M since inhibition of [(3)H]-thymidine incorporation is not observed, while there is an increase of the cell number in S phase. During this inhibition process, resveratrol increases the content of cyclins A and B1 as well as cyclin-dependent kinases Cdk1 and Cdk2. Moreover, resveratrol promotes Cdk1 phosphorylation. In conclusion, resveratrol exerts a strong inhibition of SW480 human colorectal tumor cell proliferation at least by modulating cyclin and cyclin-dependent kinase activities.
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PMID:Resveratrol, a chemopreventive agent, disrupts the cell cycle control of human SW480 colorectal tumor cells. 1211 58

Resveratrol, a polyphenolic phytoalexin found in grapes, may have potential for the prevention and treatment of human cancer. We report here that resveratrol inhibits the growth of human prostate carcinoma DU145 cells and provide a molecular explanation of the effect. Resveratrol treatment in DU145 cells resulted in a dose-dependent inhibition of cell growth and induced apoptotic cell death. The antiproliferative effect of resveratrol was associated with the inhibition of D-type cyclins and cyclin-dependent kinase (Cdk) 4 expression, and the induction of tumor suppressor p53 and Cdk inhibitor p21. Moreover, the kinase activities of cyclin E and Cdk2 were inhibited by resveratrol without alteration of their protein levels. Resveratrol treatment also up-regulated the Bax protein and mRNA expression in a dose-dependent manner; however, Bcl-2 and Bcl-xL levels were not significantly affected. These effects were found to correlate with an activation of caspase-3 and caspase-9. Taken together, our study suggests that resveratrol has a strong potential for development as an agent for the prevention of human prostate cancer.
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PMID:Antiproliferative effect of resveratrol in human prostate carcinoma cells. 1497 34

Recent evidence suggests that inflammatory cytokines and growth factors contribute to arsenite (As)-induced human carcinogenesis. We investigated the expression of inflammatory cytokine mRNAs during the transformation process induced by chronic As exposure in non-tumorigenic human osteogenic sarcoma (N-HOS) cells using gene arrays, and results were confirmed by RT-PCR and protein arrays. Caffeic acid phenethyl ester (CAPE), a naturally occurring immunomodulating agent, was used to evaluate the role of inflammatory factors in the process of As-mediated N-HOS cell transformation and in As-transformed HOS (AsT-HOS) cells. We found that an 8-week continuous exposure of N-HOS to 0.3 microM arsenite resulted in HOS cell transformation. That exposure also caused substantial decreases in inflammatory cytokine mRNAs, such as interleukin (IL) IL-1alpha, IL-2, IL-8, IL-18, MCP-1, TGF-beta2, and TNF-alpha, while it increased c-jun mRNA in a time-dependent manner. Co-incubation of N-HOS with As and CAPE (0.5-2.5 microM) prevented As-mediated declines in cytokine mRNAs in the co-treated cells, as well as their transformation to anchorage independence, while it caused decreases in c-jun mRNA. CAPE (up to 10 microM) had no effect on growth of N-HOS cells. However, CAPE (1-10 microM) treatment of AsT-HOS cells inhibited cell growth, induced cell cycle G2/M arrest, and triggered apoptosis, accompanied by changes in cytokine gene expression, as well as decreases in cyclin B1 and cdc2 abundance. Resveratrol (RV) and (-)(.) epigallocatechin gallate (EGCG), preventive agents present in grapes and green tea, respectively, induced similar changes in AsT-HOS cell growth but required much higher doses than CAPE to cause 50% growth arrest (<2.5 microM CAPE versus 25 microM RV or 50 microM EGCG). Overall, our findings suggest that inflammatory cytokines play an important role in the suppressive effects of CAPE on As-induced cell transformation and in the selective cytotoxicity of CAPE to As-transformed HOS cells.
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PMID:Caffeic acid phenethyl ester (CAPE) prevents transformation of human cells by arsenite (As) and suppresses growth of As-transformed cells. 1608 47

Resveratrol, a polyphenol found in numerous plant species, including mulberries, peanuts and grapes, has shown to possess chemopreventive properties against several cancers, and cardiovascular diseases. Recently, resveratrol has been shown to have positive effects on age longevity, lipid levels and a preventative quality against certain cancers and viral infections. Resveratrol induces apoptosis by up-regulating the expression of Bax, Bak, PUMA, Noxa, Bim, p53, TRAIL, TRAIL-R1/DR4 and TRAIL-R2/DR5 and simultaneously down-regulating the expression of Bcl-2, Bcl-XL, Mcl-1 and survivin. Resveratrol causes growth arrest at G1 and G1/S phases of cell cycle by inducing the expression of CDK inhibitors p21/WAF1/CIP1 and p27/KIP1. Resveratrol has also been shown to reduce inflammation via inhibition of prostaglandin production, cyclooxygenase-2 activity, and nuclear factor-kappaB activity. Modulation of cell signaling pathway by resveratrol explains its diverse bioactivities related with human health. Resveratrol also potentiates the apoptotic effects of cytokines, chemotherapeutic agents and gamma-radiation. Pharmacokinetic and pharmacodynamic studies demonstrated that the main target organs of resveratrol are liver and kidney, and it is metabolized by hydroxylation, glucuronidation, sulfation and hydrogenation. As a chemoprevention agent, resveratrol has been shown to inhibit tumor initiation, promotion, and progression. There is growing evidence that resveratrol can prevent or delay the onset of various cancers, heart diseases, ischemic and chemically induced injuries, pathological inflammation and viral infections. This review summarizes the molecular mechanisms of resveratrol and its clinical benefits for human diseases.
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PMID:Chemoprevention by resveratrol: molecular mechanisms and therapeutic potential. 1756 14

Mesangioproliferative glomerulonephritis is associated with overactive PDGF receptor signal transduction. We show that the phytoalexin resveratrol dose dependently inhibits PDGF-induced DNA synthesis in mesangial cells with an IC(50) of 10 microM without inducing apoptosis. Remarkably, the increased SIRT1 deacetylase activity induced by resveratrol was not necessary for this inhibitory effect. Resveratrol significantly blocked PDGF-stimulated c-Src and Akt kinase activation, resulting in reduced cyclin D1 expression and attenuated pRb phosphorylation and cyclin-dependent kinase-2 (CDK2) activity. Furthermore, resveratrol inhibited PDGFR phosphorylation at the PI 3 kinase and Grb-2 binding sites tyrosine-751 and tyrosine-716, respectively. This deficiency in PDGFR phosphorylation resulted in significant inhibition of PI 3 kinase and Erk1/2 MAPK activity. Interestingly, resveratrol increased the activity of protein tyrosine phosphatase PTP1B, which dephosphorylates PDGF-stimulated phosphorylation at tyrosine-751 and tyrosine-716 on PDGFR with concomitant reduction in Akt and Erk1/2 kinase activity. PTP1B significantly inhibited PDGF-induced DNA synthesis without inducing apoptosis. These results for the first time provide evidence that the stilbene resveratrol targets PTP1B to inhibit PDGFR mitogenic signaling.
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PMID:Resveratrol inhibits PDGF receptor mitogenic signaling in mesangial cells: role of PTP1B. 1856 37


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