UNIPROT:P10415 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Target Concepts:

Query: UNIPROT:P10415 (Bcl-2)
33,771 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Curcumin (diferuloylmethane), the yellow pigment in turmeric (Curcuma longa), is known to inhibit proliferation of cancer cells by arresting them at various phases of the cell cycle and to induce apoptosis in tumor cells. Curcumin-induced apoptosis mainly involves the activation of caspase-3 and mitochondria-mediated pathway in various cancer cells of different tissue origin. In the present study, the induction of apoptosis and cytotoxicity by curcumin in colon cancer colo 205 cells was investigated by using flow cytometry. The results demonstrated that curcumin induced cytotoxicity and apoptosis dose- and time-depedently. Curcumin induced the production of reactive oxygen species (ROS) and Ca+2, decreased the levels of mitochondria membrane potential and induced caspase-3 activity. Curcumin also promoted the expression of Bax, cytochrome C, p53 and p21 but inhibited the expression of Bcl-2. These observations suggest that curcumin may have a possible therapeutic potential in colon cancer patients.
...
PMID:Curcumin-induced apoptosis of human colon cancer colo 205 cells through the production of ROS, Ca2+ and the activation of caspase-3. 1720 Nov 58

Curcumin, an active ingredient of turmeric (Curcuma longa), inhibits proliferation and induces apoptosis in cancer cells, but the sequence of events leading to cell death is poorly defined. The objective of this study was to examine the molecular mechanisms by which multidomain pro-apoptotic Bcl-2 family members Bax and Bak regulate curcumin-induced apoptosis using mouse embryonic fibroblasts (MEFs) deficient in Bax, Bak or both genes. Curcumin treatment resulted an increase in the protein levels of both Bax and Bak, and mitochondrial translocation and activation of Bax in MEFs to trigger drop in mitochondrial membrane potential, cytosolic release of apoptogenic molecules [cytochrome c and second mitochondria-derived activator of caspases (Smac)/direct inhibitor of apoptosis protein-binding protein with low isoelectric point], activation of caspase-9 and caspase-3 and ultimately apoptosis. Furthermore, MEFs derived from Bax and Bak double-knockout (DKO) mice exhibited even greater protection against curcumin-induced release of cytochrome c and Smac, activation of caspase-3 and caspase-9 and induction of apoptosis compared with wild-type MEFs or single-knockout Bax(-/-) or Bak(-/-) MEFs. Interestingly, curcumin treatment also caused an increase in the protein level of apoptosis protease-activating factor-1 in wild-type MEFs. Smac N7 peptide enhanced curcumin-induced apoptosis, whereas Smac siRNA inhibited the effects of curcumin on apoptosis. Mature form of Smac sensitized Bax and Bak DKO MEFs to undergo apoptosis by acting downstream of mitochondria. The present study demonstrates the role of Bax and Bak as a critical regulator of curcumin-induced apoptosis and over-expression of Smac as interventional approaches to deal with Bax- and/or Bak-deficient chemoresistant cancers for curcumin-based therapy.
...
PMID:Bax and Bak genes are essential for maximum apoptotic response by curcumin, a polyphenolic compound and cancer chemopreventive agent derived from turmeric, Curcuma longa. 1727 31

Our previous studies have shown that dietary pigment curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1-6-heptadine-3,5-dione; C21H20O6] sensitizes human prostate cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L)-induced apoptosis by inhibiting nuclear factor (NF)-kappaB. In the present study, we demonstrate that activated (phosphorylated) Akt kinase plays a pivotal role in regulation of NF-kappaB and sensitization of LNCaP and PC3 prostate cancer cells to TRAIL by curcumin. Curcumin inhibited the expression of phospho-Akt (p-Akt), which was not due to activation of phosphatase and tensin homolog deleted on chromosome 10 phosphatase activity by curcumin. Because NF-kappaB is a downstream target of Akt, we investigated whether inhibition of NF-kappaB by curcumin is mediated through suppression of p-Akt. Data demonstrate that treatment of PC3 cells with SH-6 (JAm Chem Soc 125:1144-1145, 2003), a specific inhibitor of Akt, or transfection with small inhibitory RNA (siRNA)-Akt not only inhibited p-Akt but also abrogated the expression and transcriptional activity of NF-kappaB. Furthermore, overexpression of constitutively active Akt1 in cancer cells prevented the inhibition of NF-kappaB by curcumin. In addition, treatment with SH-6 or transfection with siRNA-Akt sensitized PC3 cells to TRAIL-induced cytotoxicity. On the other hand, SH-6 does not inhibit NF-kappaB or sensitize DU145 cancer cells to TRAIL because these cells do not express p-Akt. Because expression of antiapoptotic Bcl-2, Bcl-xL, and X-chromosome-linked inhibitor of apoptosis protein (XIAP) is regulated by NF-kappaB, both curcumin and SH-6 decreased the levels of these proteins in PC3 cells through inhibition of NF-kappaB. Furthermore, gene silencing of Bcl-2 with siRNA-Bcl-2 sensitized PC3 cells to TRAIL. Collectively, these data define a pathway whereby curcumin sensitizes prostate cancer cells to TRAIL by inhibiting Akt-regulated NF-kappaB and NF-kappaB-dependent antiapoptotic Bcl-2, Bcl-xL, and XIAP.
...
PMID:Curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1-6-heptadine-3,5-dione; C21H20O6] sensitizes human prostate cancer cells to tumor necrosis factor-related apoptosis-inducing ligand/Apo2L-induced apoptosis by suppressing nuclear factor-kappaB via inhibition of the prosurvival Akt signaling pathway. 1728 36

Curcumin (diferulolylmethane), an active ingredient derived from the rhizome of the plant Curcuma longa, has anticancer activity in vitro and in vivo. Although curcumin possesses chemopreventive properties against several types of cancer, the molecular mechanisms by which it inhibits cell growth and induces apoptosis are not clearly understood. Our data revealed that curcumin inhibited growth and induced apoptosis in androgen-dependent and -independent prostate cancer cells, but had no effect on normal human prostate epithelial cells. Curcumin downregulated the expression of Bcl-2, and Bcl-XL and upregulated the expression of p53, Bax, Bak, PUMA, Noxa, and Bim. Curcumin upregulated the expression of p53 as well as its phosphorylation at serine 15, and acetylation in a concentration-dependent manner. Acetylation of histone H3 and H4 was increased in cells treated with curcumin, suggesting histone modification may regulate gene expression. Treatment of LNCaP cells with curcumin resulted in translocation of Bax and p53 to mitochondria, production of reactive oxygen species, drop in mitochondrial membrane potential, release of mitochondrial proteins (cytochrome c, Smac/DIABLO and Omi/HtrA2), activation of caspase-3 and induction of apoptosis. Furthermore, curcumin inhibited expression of phosphatidyl-inositol-3 kinase (PI3K) p110 and p85 subunits, and phosphorylation of Ser 473 AKT/PKB. Downregulation of AKT by inhibitors of PI3K (Wortmannin and LY294002) and AKT, or by dominant negative AKT increased curcumin-induced apoptosis, whereas transfection of constitutively active AKT attenuated this effect. Similarly, wild-type phosphatase and tensin homolog deleted from chromosome 10 (PTEN) enhanced curcumin-induced apoptosis and, in contrast, inactive PTEN (G129E and G129R) inhibited curcumin-induced apoptosis. Overexpression of constitutively active AKT inhibited curcumin-induced p53 translocation to mitochondria, and Smac release to cytoplasm, whereas inhibition of AKT by dominant negative AKT enhanced curcumin-induced p53 translocation to mitochondria and Smac release. Our study establishes a role for AKT in modulating the direct action of p53 on the caspase-dependent mitochondrial death pathway and suggests that these important biological molecules interact at the level of the mitochondria to influence curcumin sensitivity. These properties of curcumin strongly suggest that it could be used as a cancer chemopreventive agent.
...
PMID:Involvement of Bcl-2 family members, phosphatidylinositol 3'-kinase/AKT and mitochondrial p53 in curcumin (diferulolylmethane)-induced apoptosis in prostate cancer. 1733 30

Patients with advanced cancer exhibit multifaceted defects in their immune capacity, which are likely to contribute to an increased susceptibility to infections and disease progression. We demonstrated earlier that curcumin inhibits tumor growth and prevents immune cell death in tumor-bearing hosts. Here we report that tumor-induced immunodepletion involves apoptosis of thymic CD4+/CD8+ single/double positive cells as well as loss of circulating CD4+/CD8+ T cells. Administration of curcumin to tumor-bearing animals resulted in restoration of progenitor, effecter, and circulating T cells. In fact, tumor burden decreased the expression level of the pro-proliferative protein Bcl-2 while increasing the pro-apoptotic protein Bax in T cells. Curcumin down-regulated the Bax level while augmenting Bcl-2 expression in these cells, thereby protecting the immunocytes from tumor-induced apoptosis. A search for the upstream mechanism revealed down-regulation of the common cytokine receptor gamma chain (gammac) expression in T cells by tumor-secreted prostaglandin E2. As a result, Jak-3 and Stat-5a phosphorylation and to a lesser extent Stat-5b phosphorylation were also decreased in T cells. These entire phenomena could be reverted back by curcumin, indicating that this phytochemical restored the cytokine-dependent Jak-3/Stat-5a signaling pathway in T cells of tumor bearers. Overexpressed Stat-5a/constitutively active Stat-5a1*6 but not Stat-5b could efficiently elevate Bcl-2 levels and protect T cells from tumor-induced death, whereas C-terminal truncated Stat-5a713 overexpression failed to do so, indicating the importance of Stat-5a signaling in T cell survival. Thus, these results raise the possibility of inclusion of curcumin in successful therapeutic regimens against cancer.
...
PMID:Curcumin prevents tumor-induced T cell apoptosis through Stat-5a-mediated Bcl-2 induction. 1739 82

Gemcitabine is currently the best treatment available for pancreatic cancer, but the disease develops resistance to the drug over time. Agents that can either enhance the effects of gemcitabine or overcome chemoresistance to the drug are needed for the treatment of pancreatic cancer. Curcumin, a component of turmeric (Curcuma longa), is one such agent that has been shown to suppress the transcription factor nuclear factor-kappaB (NF-kappaB), which is implicated in proliferation, survival, angiogenesis, and chemoresistance. In this study, we investigated whether curcumin can sensitize pancreatic cancer to gemcitabine in vitro and in vivo. In vitro, curcumin inhibited the proliferation of various pancreatic cancer cell lines, potentiated the apoptosis induced by gemcitabine, and inhibited constitutive NF-kappaB activation in the cells. In vivo, tumors from nude mice injected with pancreatic cancer cells and treated with a combination of curcumin and gemcitabine showed significant reductions in volume (P = 0.008 versus control; P = 0.036 versus gemcitabine alone), Ki-67 proliferation index (P = 0.030 versus control), NF-kappaB activation, and expression of NF-kappaB-regulated gene products (cyclin D1, c-myc, Bcl-2, Bcl-xL, cellular inhibitor of apoptosis protein-1, cyclooxygenase-2, matrix metalloproteinase, and vascular endothelial growth factor) compared with tumors from control mice treated with olive oil only. The combination treatment was also highly effective in suppressing angiogenesis as indicated by a decrease in CD31(+) microvessel density (P = 0.018 versus control). Overall, our results suggest that curcumin potentiates the antitumor effects of gemcitabine in pancreatic cancer by suppressing proliferation, angiogenesis, NF-kappaB, and NF-kappaB-regulated gene products.
...
PMID:Curcumin potentiates antitumor activity of gemcitabine in an orthotopic model of pancreatic cancer through suppression of proliferation, angiogenesis, and inhibition of nuclear factor-kappaB-regulated gene products. 1744 Jan

Xanthorrhizol is a sesquiterpenoid compound extracted from the rhizome of Curcuma xanthorrhiza. This study investigated the antiproliferative effect and the mechanism of action of xanthorrhizol on human hepatoma cells, HepG2, and the mode of cell death. An antiproliferative assay using methylene blue staining revealed that xanthorrhizol inhibited the proliferation of the HepG2 cells with a 50% inhibition of cell growth (IC50) value of 4.17 +/- 0.053 microg/ml. The antiproliferative activity of xanthorrhizol was due to apoptosis induced in the HepG2 cells and not necrosis, which was confirmed by the Tdt-mediated dUTP nick end labeling (TUNEL) assay. The xanthorrhizol-treated HepG2 cells showed typical apoptotic morphology such as DNA fragmentation, cell shrinkage and elongated lamellipodia. The apoptosis mediated by xanthorrhizol in the HepG2 cells was associated with the activation of tumor suppressor p53 and down-regulation of antiapoptotic Bcl-2 protein expression, but not Bax. The levels of Bcl-2 protein expression decreased 24-h after treatment with xanthorrhizol and remained lower than controls throughout the experiment, resulting in a shift in the Bax to Bcl-2 ratio thus favouring apoptosis. The processing of the initiator procaspase-9 was detected. Caspase-3 was also found to be activated, but not caspase-7. Xanthorrhizol exerts antiproliferative effects on HepG2 cells by inducing apoptosis via the mitochondrial pathway.
...
PMID:Regulation of p53-, Bcl-2- and caspase-dependent signaling pathway in xanthorrhizol-induced apoptosis of HepG2 hepatoma cells. 1746 28

Glioblastoma is the most malignant human brain tumor that shows poor response to existing therapeutic agents. Search continues for an effective therapy for controlling this deadliest brain tumor. Curcumin (CCM), a polyphenolic compound from Curcuma longa, possesses anti-cancer properties in both in vitro and in vivo. In the present investigation, we evaluated the therapeutic efficacy of CCM against human malignant glioblastoma U87MG cells. Trypan blue dye exclusion test showed decreased viability of U87MG cells with increasing dose of CCM. Wright staining and ApopTag assay, respectively, showed the morphological and biochemical features of apoptosis in U87MG cells treated with 25 microM and 50 microM of CCM for 24 h. Western blotting showed activation of caspase-8, cleavage of Bid to tBid, increase in Bax:Bcl-2 ratio, and release of cytochrome c from mitochondria followed by activation of caspase-9 and caspase-3 for apoptosis. Also, CCM treatments increased cytosolic level of Smac/Diablo to suppress the inhibitor-of-apoptosis proteins and down regulated anti-apoptotic nuclear factor kappa B (NFkappaB), favoring the apoptosis. Increased activities of calpain and caspase-3 cleaved 270 kDa alpha-spectrin at specific sites generating 145 kDa spectrin break down product (SBDP) and 120 kDa SBDP, respectively, leading to apoptosis in U87MG cells. Results show that CCM is an effective therapeutic agent for suppression of anti-apoptotic factors and activation of calpain and caspase proteolytic cascades for apoptosis in human malignant glioblastoma cells.
...
PMID:Curcumin suppressed anti-apoptotic signals and activated cysteine proteases for apoptosis in human malignant glioblastoma U87MG cells. 1756 68

Curcumin was found to be cytotoxic in nature to a wide variety of tumor cell lines of different tissue origin. The action of curcumin is dependent on with the cell type, the concentration of curcumin (IC50: 2-40 microg/mL), and the time of the treatment. The major mechanism by which curcumin induces cytotoxicity is the induction of apoptosis. Curcumin decreased the expression of antiapoptotic members of the Bcl-2 family and elevated the expression of p53, Bax, procaspases 3, 8, and 9. Curcumin prevents the entry of nuclear factor KB (NF-KB) into the nucleus there by decreasing the expression of cell cycle regulatory proteins and survival factors such as Bcl-2 and survivin. Curcumin arrested the cell cycle by preventing the expression of cyclin D1, cdk-1 and cdc-25. Curcumin inhibited the growth of transplantable tumors in different animal models and increased the life span of tumor-harboring animals. Curcumin inhibits metastasis of tumor cells as shown in in vitro as well as in vivo models, and the possible mechanism is the inhibition of matrix metalloproteases. Curcumin was found to suppress the expression of cyclooxygenase-2, vascular endothelial growth factor, and intercellular adhesion molecule- and elevated the expression of antimetastatic proteins, the tissue inhibitor of metalloproteases-2, nonmetastatic gene 23, and Ecadherin. These results indicate that curcumin acts at various stages of tumor cell progression.
...
PMID:Antitumor, anti-invasion, and antimetastatic effects of curcumin. 1756 10

An integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of these agents that can inhibit tumour progression and reduce the risk of metastasis. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclooxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. The herbs that are traditionally used for anticancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose-response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as adaptogens, potentially enhancing the efficacy of the conventional therapies.
...
PMID:Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer-Part 1. 1757 37

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