Induction of cIAP-2 in Human Colon Cancer Cells through PKCδ/NF-κBстатья из журнала
Аннотация: Activation of protein kinase C (PKC) prevents apoptosis in certain cells; however, the mechanisms are largely unknown. Inhibitors of apoptosis (IAP) family members, including NAIP, cIAP-1, cIAP-2, XIAP/hILP, survivin, and BRUCE, block apoptosis by binding and potently inhibiting caspases. Activation of NF-κB contributes to cIAP-2 induction; however, the cellular mechanisms regulating cIAP-2 expression have not been entirely defined. In this study, we examined the role of the PKC and NF-κB pathways in the regulation of cIAP-2 in human colon cancers. We found that cIAP-2 mRNA levels were markedly increased in human colon cancer cells by treatment with the phorbol ester, phorbol-12-myristate-13-acetate (PMA), or bryostatin 1. Inhibitors of the Ca2+-independent, novel PKC isoforms, but not inhibitors of MAPK, PI3-kinase, or PKA, blocked PMA-stimulated cIAP-2 mRNA expression, suggesting a role of PKC in PMA-mediated cIAP-2 induction. Pretreatment with the PKCδ-selective inhibitor rottlerin or transfection with an antisense PKCδ oligonucleotide inhibited PMA-induced cIAP-2 expression, whereas cotransfection with a PKCδ plasmid induced cIAP-2 promoter activity, which, taken together, identifies a role for PKCδ in cIAP-2 induction. Treatment with the proteasome inhibitor, MG132 or inhibitors of NF-κB (e.g. PDTC and gliotoxin), decreased PMA-induced up-regulation of cIAP-2. PMA-induced NF-κB activation was blocked by either GF109203x, MG132, PDTC, or gliotoxin. Moreover, overexpression of PKCδ-induced cIAP-2 promoter activity and increased NF-κB transactivation, suggesting regulation of cIAP-2 expression by a PKCδ/NF-κB pathway. In conclusion, our findings demonstrate a role for a PKC/NF-κB-dependent pathway in the regulation of cIAP-2 expression in human colon cancer cells. These data suggest a novel mechanism for the anti-apoptotic function mediated by the PKCδ/NF-κB/cIAP-2 pathway in certain cancers. Activation of protein kinase C (PKC) prevents apoptosis in certain cells; however, the mechanisms are largely unknown. Inhibitors of apoptosis (IAP) family members, including NAIP, cIAP-1, cIAP-2, XIAP/hILP, survivin, and BRUCE, block apoptosis by binding and potently inhibiting caspases. Activation of NF-κB contributes to cIAP-2 induction; however, the cellular mechanisms regulating cIAP-2 expression have not been entirely defined. In this study, we examined the role of the PKC and NF-κB pathways in the regulation of cIAP-2 in human colon cancers. We found that cIAP-2 mRNA levels were markedly increased in human colon cancer cells by treatment with the phorbol ester, phorbol-12-myristate-13-acetate (PMA), or bryostatin 1. Inhibitors of the Ca2+-independent, novel PKC isoforms, but not inhibitors of MAPK, PI3-kinase, or PKA, blocked PMA-stimulated cIAP-2 mRNA expression, suggesting a role of PKC in PMA-mediated cIAP-2 induction. Pretreatment with the PKCδ-selective inhibitor rottlerin or transfection with an antisense PKCδ oligonucleotide inhibited PMA-induced cIAP-2 expression, whereas cotransfection with a PKCδ plasmid induced cIAP-2 promoter activity, which, taken together, identifies a role for PKCδ in cIAP-2 induction. Treatment with the proteasome inhibitor, MG132 or inhibitors of NF-κB (e.g. PDTC and gliotoxin), decreased PMA-induced up-regulation of cIAP-2. PMA-induced NF-κB activation was blocked by either GF109203x, MG132, PDTC, or gliotoxin. Moreover, overexpression of PKCδ-induced cIAP-2 promoter activity and increased NF-κB transactivation, suggesting regulation of cIAP-2 expression by a PKCδ/NF-κB pathway. In conclusion, our findings demonstrate a role for a PKC/NF-κB-dependent pathway in the regulation of cIAP-2 expression in human colon cancer cells. These data suggest a novel mechanism for the anti-apoptotic function mediated by the PKCδ/NF-κB/cIAP-2 pathway in certain cancers. Colorectal cancer is the third leading cause of cancer-related deaths in the United States with ∼130,000 new cases diagnosed per year (1Jemal A. Murray T. Samuels A. Ghafoor A. Ward E. Thun M.J. CA Cancer J. Clin. 2003; 53: 5-26Crossref PubMed Scopus (3374) Google Scholar). Despite advances in surgical management and multimodality therapy, ∼50% of patients with cancers of the colon and rectum die from their disease (2Declan Fleming R.Y. Surg. Oncol. 1998; 7: 125-137Crossref PubMed Scopus (15) Google Scholar). A significant obstacle for the successful management of patients with colorectal cancer is intrinsic drug resistance or, in patients who initially respond to chemotherapy, acquired drug resistance (3Gorlick R. Bertino J.R. Semin. Oncol. 1999; 26: 606-611PubMed Google Scholar). Alterations in genes that confer a survival and anti-apoptotic advantage and the related signaling transduction pathways involved in the regulation of the cell cycle or in DNA damage repair may result in the resistance of populations of cancer cells to chemotherapy (3Gorlick R. Bertino J.R. Semin. Oncol. 1999; 26: 606-611PubMed Google Scholar). Programmed cell death, often referred to as apoptosis, is a physiological cell suicide program that is critical for the development and maintenance of healthy tissues. Caspases are synthesized initially as single polypeptide chains representing latent precursors that undergo proteolytic processing at specific aspartic acid residues to produce subunits that form the active heterotetrameric protease (4Deveraux Q.L. Reed J.C. Genes Dev. 1999; 13: 239-252Crossref PubMed Scopus (2281) Google Scholar, 5Patel T. Gores G.J. Kaufmann S.H. FASEB J. 1996; 10: 587-597Crossref PubMed Scopus (538) Google Scholar, 6Cohen G.M. Biochem. 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IAPs have been shown to be involved in the resistance of certain tumor cells to chemotherapeutic drugs or other apoptotic agents (12Cheng J.Q. Jiang X. Fraser M. Li M. Dan H.C. Sun M. Tsang B.K. Drug Resist. Updat. 2002; 5: 131-146Crossref PubMed Scopus (127) Google Scholar). For example, overexpression of cIAP-2 appears to be responsible for sustained neutrophilia in some cases of chronic neutrophilic leukemia (13Hasegawa T. Suzuki K. Sakamoto C. Ohta K. Nishiki S. Hino M. Tatsumi N. Kitagawa S. Blood. 2003; 101: 1164-1171Crossref PubMed Scopus (109) Google Scholar). cIAP-2 has been functionally implicated in TNF induction of the ubiquitous transcription factor, NF-κB, and protection from apoptosis (10Chu Z.L. McKinsey T.A. Liu L. Gentry J.J. Malim M.H. Ballard D.W. Proc. Natl. Acad. Sci. U. S. A. 1997; 94: 10057-10062Crossref PubMed Scopus (825) Google Scholar, 14Mitsiades N. Mitsiades C.S. Poulaki V. Chauhan D. Richardson P.G. Hideshima T. Munshi N. Treon S.P. Anderson K.C. Blood. 2002; 99: 4079-4086Crossref PubMed Scopus (370) Google Scholar). inhibitors of apoptosis protein kinase C phosphatidylinositol glyceraldehyde-3-phosphate dehydrogenase phorbol-12-myristate-13-acetate pyrrolidine dithiocarbamate fetal calf serum electrophoretic mobility shift assays cAMP-dependent protein kinase mitogen-activated protein kinase extracellular signal-regulated kinase hemagglutinin RNase Protection Assay. The protein kinase C (PKC) family, some isoforms of which are stimulated by phorbol esters such as phorbol-12-myristate-13-acetate (PMA), is responsible for transducing many cellular signals during a variety of cellular processes such as mitogenesis, cellular metabolism, differentiation, tumor promotion, and apoptosis (15Blobe G.C. Obeid L.M. Hannun Y.A. Cancer Metastasis Rev. 1994; 13: 411-431Crossref PubMed Scopus (259) Google Scholar, 16Liu W.S. Heckman C.A. Cell Signal. 1998; 10: 529-542Crossref PubMed Scopus (444) Google Scholar, 17Deszo E.L. Brake D.K. 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Our laboratory is interested in the regulation of proteins and signaling pathways which can contribute to the inhibition of cell death in resistant cancer cells. Previously, we have shown that inhibition of NF-κB or PI 3-kinase sensitizes colon cancer cells to TRAIL-induced apoptosis (35Thomas R.P. Farrow B.J. Kim S. May M.J. Hellmich M.R. Evers B.M. Surgery. 2002; 132: 127-134Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar, 36Wang Q. Li N. Wang X. Kim M.M. Evers B.M. Clin. Cancer Res. 2002; 8: 1940-1947PubMed Google Scholar). The purpose of our present study was to better define the cellular mechanisms regulating the expression of the IAP family members in human colon cancer cells. Here, we show that expression of one of the IAP family member, cIAP-2, is preferentially induced in human colon cancer cells following PMA treatment; inhibition of Ca2+-independent, novel PKC isoforms, but not inhibition of MAPK, PI3-kinase and PKA, blocked PMA-stimulated cIAP-2 mRNA expression, suggesting a role for PKC in PMA-mediated cIAP-2 induction. Further studies utilizing complementary approaches identified PKCδ as a critical isoform mediating these effects. Finally, a role for NF-κB activation, mediated through PKC, acts ultimately to induce cIAP-2 expression. Thus, these results demonstrate that the PKCδ/NF-κB pathway plays an important role in the regulation of the anti-apoptosis protein cIAP-2 in human colon cancer cells. Materials—PMA, wortmannin, and actinomycin D were purchased from Sigma Chemical Company. Bryostatin 1 was from Biomol Research Laboratories Inc. (Plymouth meeting, PA). Bis-indolylmaleimide (GF109203x), PD98059, Gö6983, Gö-6976, rottlerin, H89, MG132, pyrrolidine dithiocarbamate (PDTC), and gliotoxin were from Calbiochem (San Diego, CA). The NF-κB oligonucleotide was purchased from Promega (Madison, WI). Anti-cIAP-2 antibody was purchased from R&D Systems (Minneapolis, MN). Antibodies against p50, p65 and PKC isoforms α, βI, βII, γ, δ, ϵ, η, θ, ι, ζ, μ and myelin basic protein (MBP) were obtained from Santa Cruz Biotechnology (Santa Cruz, CA). The anti-actin antibody was purchased from Sigma. The rat monoclonal anti-hemagglutinin (HA) antibody (clone 3F10) was from Roche Applied Science. The pNF-κB-luc was from Clontech (Palo Alto, CA) and the pRL-Tk-luc reporter plasmid was purchased from Promega (Madison, WI). The cIAP-2 promoter-luciferase construct was a gift from Tae H. Lee (Yonsei University, Seoul 120-749, South Korea) (37Hong S.Y. Yoon W.H. Park J.H. Kang S.G. Ahn J.H. Lee T.H. J. Biol. Chem. 2000; 275: 18022-18028Abstract Full Text Full Text PDF PubMed Scopus (107) Google Scholar). The PKCδ expression plasmid (pTB701-HA-PKCδ) and the control plasmid (pTB701-HA) were kindly provided by Dr. Yoshitaka Ono (Kobe University, Japan). RiboQuant MultiProbe RNase Protection Assay System was from BD Pharmingen (San Diego, CA). [γ-32P]ATP (3,000 Ci/mmol) was from Amersham Biosciences. The antisense and sense PKCδ oligonucleotides were synthesized as phosphorothioate derivatives from Invitrogen (Carlsbad, CA). Total RNA was isolated using Ultraspec RNA (Biotecx Laboratories, Houston, TX). Tissue culture media and reagents were obtained from Invitrogen. LipofectAMINE was purchased from Invitrogen. Polyvinylidene difluoride (PVDF) membranes for Western blots were from Millipore Corp. (Bedford, MA). The enhanced chemiluminescence (ECL) system for Western immunoblot analysis was purchased from Amersham Biosciences. Cell Culture—The human colon cancer cell lines Caco-2, LoVo, DLD1, SW480, and HCT116 were purchased from ATCC. The human colon cancer cell lines, KM20 and KM12C, were obtained from Dr. Isaiah Fidler (M. D. Anderson, Houston, TX). Caco-2, KM20, KM12C, LoVo, and DLD1 cells were incubated in MEM supplemented with either 15% (Caco-2) or 10% (LoVo, DLD1, KM20, KM12C) fetal calf serum (FCS), respectively. The human colon cancer cell line SW480 was grown in RPMI 1640 supplemented 10% FCS. The human colon cancer cell line HCT116 was maintained in McCoy's 5A supplemented with 10% FCS. PMA, and inhibitors were initially dissolved in dimethyl sulfoxide (Me2SO) and compared with cells treated with Me2SO at the same final concentration. RNA Isolation and RNase Protection Assays—RNA was isolated from cells using Ultraspec RNA according to the manufacturer's protocol. RiboQuant MultiProbe RNase Protection Assay (RPA) System was used for the detection of multiple, specific mRNA species as we have previously described (38Wang Q. Wang X. Hernandez A. Hellmich M.R. Gatalica Z. Evers B.M. J. Biol. Chem. 2002; 277: 36602-36610Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar). 32P-labeled antisense RNA probes were prepared using the Human Apoptosis hAPO-5 Template Set and hybridization performed according to the manufacturer's protocol. Protein Preparation and Western Immunoblot—Western immunoblot analyses were performed as described previously (39Wang Q. Ding Q. Dong Z. Ehlers R.A. Evers B.M. Anticancer Res. 2000; 20: 75-83PubMed Google Scholar). Cells were lysed with TNN buffer (50 mm Tris-HCl, pH 7.5, 150 mm NaCl, 0.5 mm Nonidet P-40, 50 mm NaF, 1 mm sodium orthovanadate, 1 mm dithiothreitol, and 1 mm phenylmethylsulfonyl fluoride, and 25 μg/ml each of aprotinin, leupeptin, and pepstatin A) at 4 °C for 30 min. Lysates were clarified by centrifugation (10,000 × g for 30 min at 4 °C) and protein concentrations determined using the method of Bradford (40Bradford M.M. Anal. Biochem. 1976; 72: 248-254Crossref PubMed Scopus (216391) Google Scholar). Briefly, total protein was resolved on a 10% polyacrylamide gel and transferred to polyvinylidene difluoride membranes. Filters were incubated overnight at 4 °C in blotting solution (Tris-buffered saline containing 5% nonfat dried milk and 0.1% Tween 20). Protein expression was detected with antibodies to various PKC isoforms, cIAP-2, HA, or to β-actin following blotting with a horseradish peroxidase-conjugated secondary antibody and visualized using ECL detection. PKCδ Kinase Assay—PKCδ activity was determined in cell extracts as described (41Brandt D.T. Goerke A. Heuer M. Gimona M. Leitges M. Kremmer E. Lammers R. Haller H. Mischak H. J. Biol. Chem. 2003; 278: 34073-34078Abstract Full Text Full Text PDF PubMed Scopus (80) Google Scholar). Briefly, total PKCδ was determined by measuring the incorporation of 32P into MBP. Extracts from Caco-2 cells treatment with or without PMA were incubated with PKCδ antibody overnight and with protein A beads for 3 h at 4 °C by gentle rocking. Immunocomplexed beads were washed twice with cell lysis buffer and twice with kinase buffer (25 mm Tris, pH 7.4; 2 mm dithiothreitol; 0.1 mm Na3 VO4; 10 mm MgCl2; and 5 μCi of [γ-32P]ATP). Immunocomplexes were resuspended in 40 μl of kinase buffer supplemented with 10 μm ATP and 5 μg of MBP and incubated for 30 min at 30 °C. Kinase reactions were terminated with SDS sample buffer. Samples were size-fractionated by SDS-PAGE and 32P-labeled MBP was quantified autoradiographically after fixing and drying the gel. Preparation of Nuclear Extracts and Electrophoretic Mobility Shift Assays (EMSAs)—The nuclear extracts were prepared from Caco-2 cells according to the procedure described by Han et al. (42Han Y. Meng T. Murray N.R. Fields A.P. Brasier A.R. J. Biol. Chem. 1999; 274: 939-947Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar). EMSAs were performed as described previously (43Wang Q. Kim S. Wang X. Evers B.M. Biochem. Biophys. Res. Commun. 2000; 273: 853-858Crossref PubMed Scopus (20) Google Scholar) with minor modifications. Nuclear extracts (10 μg) were incubated with 40,000 cpm of 32P-labeled NF-κB consensus oligonucleotide (5′-AGTTGAGGGGACTTTCCCAGG-3′) and 2 μg of poly(dA·dT) in a buffer containing 8% glycerol, 100 mm NaCl, 5 mm MgCl2, 5 mm dithiothreitol, and 0.1 μg/ml phenylmethylsulfonyl fluoride in a final volume of 20 μl, for 15 min at room temperature. For supershift studies, 2 μl of antiserum was added to the nuclear protein for 20 min at room temperature prior to the addition of labeled probe. The complexes were fractionated on 6% native polyacrylamide gels run in 1× TBE buffer (89 mm Tris, 89 mm boric acid, and 2.0 mm EDTA), dried, and exposed to Kodak X-AR film at -70 °C. Competition binding experiments were performed by the addition of the nonradioactive oligonucleotide, in 100-fold molar excess, at the time of addition of radioactive probe. Transient Transfections, Luciferase Assays—Caco-2 cells (0.1 × 106/well) were seeded in 6-well plates 24 h prior to transfection. Cells were then transfected with 1 μg of pTB701-HA vector or pTB701-HA-PKCδ and 0.3 μg of the cIAP-2 promoter-luciferase construct or pNF-κB-luc construct using LipofectAMINE following the supplier's instructions. The pRL-Tk-luc plasmid (0.05 μg per well) was co-transfected to normalize for variation in transfection efficiency. After 12 h, the cells were washed with phosphate-buffered saline and then maintained in fresh medium for 36 h prior to harvest. In each experiment, the pGL2 plasmid was also transfected in separate wells to compare the specific activity of promoter-reporter constructs with the basic activity of the promoterless plasmid. Luciferase assays were performed as described previously (43Wang Q. Kim S. Wang X. Evers B.M. Biochem. Biophys. Res. Commun. 2000; 273: 853-858Crossref PubMed Scopus (20) Google Scholar). Briefly, 48 h after transfection, the cells were rinsed with phosphate-buffered saline, harvested and lysed with 1× cell culture lysis reagent. Luciferase activity in 20 μl of extract was assayed with the dual luciferase assay system. Light emissions were integrated for the initial 10 s of emission by using a Monolight 2010 luminometer (Analytical Luminescence Laboratory). Transient transfection of cells with PKCδ oligonucleotides was performed using antisense (5′-CCCACCATGGCGCCGTTC-3′) and sense oligonucleotide sequences to the translation start site of PKCδ (44Shih S.C. Mullen A. Abrams K. Mukhopadhyay D. Claffey K.P. J. Biol. Chem. 1999; 274: 15407-15414Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar). Oligonucleotides were dissolved in sterile deionized water to a final concentration of 1 mm, aliquoted, and stored at -20 °C until use. Antisense and sense oligonucleotides to PKCδ (1 μm) were transfected into Caco-2 cells using LipofectAMINE. After transfection, cells were incubated 48 h before treatment. PMA Treatment Induces cIAP-2 mRNA and Protein Expression in Caco-2 Cells—PKC isoforms are involved in the regulation of certain anti-apoptotic proteins (23Nishizuka Y. FASEB J. 1995; 9: 484-496Crossref PubMed Scopus (2365) Google Scholar, 24Hug H. Sarre T.F. Biochem. J. 1993; 291: 329-343Crossref PubMed Scopus (1219) Google Scholar). The expression of cIAP-2, a member of the IAP family of anti-apoptotic proteins (4Deveraux Q.L. Reed J.C. Genes Dev. 1999; 13: 239-252Crossref PubMed Scopus (2281) Google Scholar), can be induced by NF-κB resulting in the protection of certain cells from apoptosis (10Chu Z.L. McKinsey T.A. Liu L. Gentry J.J. Malim M.H. Ballard D.W. Proc. Natl. Acad. Sci. U. S. A. 1997; 94: 10057-10062Crossref PubMed Scopus (825) Google Scholar, 14Mitsiades N. Mitsiades C.S. Poulaki V. Chauhan D. Richardson P.G. Hideshima T. Munshi N. Treon S.P. Anderson K.C. Blood. 2002; 99: 4079-4086Crossref PubMed Scopus (370) Google Scholar, 37Hong S.Y. Yoon W.H. Park J.H. Kang S.G. Ahn J.H. Lee T.H. J. Biol. Chem. 2000; 275: 18022-18028Abstract Full Text Full Text PDF PubMed Scopus (107) Google Scholar). To better delineate upstream signaling pathways responsible for cIAP-2 induction, the human colon cancer cell line Caco-2 was treated with the phorbol ester PMA, and RNA extracted for RPA using a multiprobe (hAPO-5; BD Pharmingen) containing cDNAs for a number of anti-apoptotic genes as well as the housekeeping genes L32 and GAPDH (Fig. 1). Treatment with PMA (100 nm) markedly induced cIAP-2 mRNA expression over a time course with maximal induction occurring 4 h after treatment (Fig. 1A). In contrast, xIAP, another IAP family member, was not affected by PMA treatment. The expression of TRAF-4, a member of the tumor necrosis factor (TNF) receptor-associated factor (TRAF) family of putative signal-transducing proteins, and cIAP-1 was slightly increased with PMA. The remainder of the apoptosis-related genes in this multiprobe template were either not expressed in Caco-2 cells or the level was not affected by PMA. The expression of L32 and GAPDH remained constant thus demonstrating equal loading. Caco-2 cells were then treated with varying concentrations of PMA and harvested at 4 h (Fig. 1B). Induction of cIAP-2 was noted with the lowest concentration (5 nm); maximal expression occurred with dosages between 20 and 50 nm. Once again, expression of TRAF-4 was minimally affected and expression of L32 and GAPDH remained constant. Steady-state mRNA levels may be modulated by transcriptional or post-transcriptional mechanisms. To assess whether the induction of cIAP-2 was due to an increase in transcription, Caco-2 cells were treated with PMA (100 nm) for 4 h in the presence or absence of actinomycin D (10 μg/ml), which inhibits transcription by inhibiting DNA-primed RNA polymerase (45Shi M.M. Kugelman A. Iwamoto T. Tian L. Forman H.J. J. Biol. Chem. 1994; 269: 26512-26517Abstract Full Text PDF PubMed Google Scholar), and assessed by RPA (Fig. 1C). As expected, treatment with PMA alone induced cIAP-2 expression; this induction was blocked by actinomycin D suggesting that PMA increases cIAP-2 expression levels by increasing transcription. There was no effect of either PMA or actinomycin D on the expression of TRPM-2 (testosterone repressed prostate message 2), an apoptotic gene, or the housekeeping genes L32 and GAPDH. We next determined whether the induction of cIAP-2 mRNA levels by PMA also resulted in the corresponding induction of cIAP-2 protein expression (Fig. 1D). Treatment with PMA (100 nm) increased cIAP-2 protein expression. The blot was stripped and reprobed with β-actin to ensure equal protein loading. Taken together, these results identify induction of cIAP-2 mRNA and protein levels with PMA treatment. Regulation of PMA-stimulated cIAP-2 Expression Through the PKC Pathway—To better delineate the signaling pathway leading to PMA-mediated cIAP-2 induction, Caco-2 cells were pretreated for 30 min with inhibitors to PKC (GF109203x), MEK (PD98059), PI 3-kinase (wortmannin), or PKA (H89) prior to addition of PMA (100 nm). Cells were harvested 4 h later and RNA extracted for RPA (Fig. 2A). As expected, PMA increased cIAP-2 expression (lane 2); this induction was completely blocked by treatment with GF109203x (lane 3). In contrast, treatment with PD98059, wortmannin, or H89 did not block cIAP-2 induction by PMA (lanes 4-6). Treatment with the inhibitors alone had no effect on cIAP-2 expression (lanes 7-10). Similar to PMA, the non-phorbol ester PKC agonist bryostatin-1, induced cIAP-2 expression; this induction was completely blocked by GF109203x treatment (Fig. 2B). Minimal to no effect on xIAP or TRAF-4 expression was noted with either PMA, bryostatin 1 or the inhibitors. In a similar fashion, L32 and GAPDH expression remained constant indicating equal loading. Bryostatin stimulates various PKC isoforms in certain cell lines (46Yoo J. Nichols A. Song J.C. Mammen J. Calvo I. Worrell R.T. Cuppoletti J. Matlin K. Matthews J.B. Am. J. Physiol. Gastrointest Liver Physiol. 2003; 284: G703-G712Crossref PubMed Scopus (25) Google Scholar, 47Brodie C. Bogi K. Acs P. Lorenzo P.S. Baskin L. Blumberg P.M. J. Bi
Год издания: 2003
Авторы: Qingding Wang, Xiaofu Wang, B. Mark Evers
Издательство: Elsevier BV
Источник: Journal of Biological Chemistry
Ключевые слова: NF-κB Signaling Pathways, Signaling Pathways in Disease, Immune Response and Inflammation
Другие ссылки: Journal of Biological Chemistry (PDF)
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Открытый доступ: hybrid
Том: 278
Выпуск: 51
Страницы: 51091–51099