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Tang YQ, Han BM, Yao XQ, Hong Y, Wang Y, Zhao FJ, Yu SQ, Sun XW, Xia SJ. Chimeric molecules facilitate the degradation of androgen receptors and repress the growth of LNCaP cells. Asian J Androl 2009; 11:119-26. [PMID: 19050678 PMCID: PMC3735208 DOI: 10.1038/aja.2008.26] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Accepted: 10/13/2008] [Indexed: 11/09/2022] Open
Abstract
Post-translational degradation of protein plays an important role in cell life. We employed chimeric molecules (dihydrotestosterone-based proteolysis-targeting chimeric molecule [DHT-PROTAC]) to facilitate androgen receptor (AR) degradation via the ubiquitin-proteasome pathway (UPP) and to investigate the role of AR in cell proliferation and viability in androgen-sensitive prostate cancer cells. Western blot analysis and immunohistochemistry were applied to analyse AR levels in LNCaP cells after DHT-PROTAC treatment. Cell counting and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell viability assay were used to evaluate cell proliferation and viability after AR elimination in both LNCaP and PC-3 cells. AR was tagged for elimination via the UPP by DHT-PROTAC, and this could be blocked by proteasome inhibitors. Degradation of AR depended on DHT-PROTAC concentration, and either DHT or an ALAPYIP-(arg)(8) peptide could compete with DHT-PROTAC. Inhibition of cell proliferation and decreased viability were observed in LNCaP cells, but not in PC-3 or 786-O cells after DHT-PROTAC treatment. These data indicate that AR elimination is facilitated via the UPP by DHT-PROTAC, and that the growth of LNCaP cells is repressed after AR degradation.
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Affiliation(s)
- Yue-Qing Tang
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
- Institute of Urology, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Bang-Min Han
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Xin-Quan Yao
- Department of Urology, Wujiang Third People's Hospital, Suzhou 215228, China
| | - Yan Hong
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
- Institute of Urology, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Yan Wang
- Department of Immunology, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Fu-Jun Zhao
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Sheng-Qiang Yu
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
- Institute of Urology, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Xiao-Wen Sun
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Shu-Jie Xia
- Department of Urology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai 200025, China
- Institute of Urology, Shanghai Jiao Tong University, Shanghai 200025, China
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Fukuda H, Irie K, Nakahara A, Ohigashi H, Wender PA. Solid-phase synthesis, mass spectrometric analysis of the zinc-folding, and phorbol ester-binding studies of the 116-mer peptide containing the tandem cysteine-rich C1 domains of protein kinase C gamma. Bioorg Med Chem 1999; 7:1213-21. [PMID: 10428394 DOI: 10.1016/s0968-0896(99)00037-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Tumor-promoting phorbol esters activate protein kinase C (PKC) isozymes by binding to the zinc-finger like cysteine-rich domains in the N-terminal regulatory region. Our recent studies have revealed that only PKCgamma has two high affinity phorbol ester-binding domains, providing a structural blueprint for the rational design of PKCgamma-selective modulators for the treatment of neuropathic pain. To extend this approach, the 116-mer peptide containing the double cysteine-rich motifs of PKCgamma (gamma-C1A-C1B) has been synthesized for the first time using an Fmoc-solid phase strategy with a stepwise chain elongation. This peptide was purified by the reversed phase HPLC to give satisfactory mass data (MALDI-TOF-MS and ESI-TOF-MS). The peptide was successfully folded by zinc treatment and the folded peptide was analyzed intact under neutral conditions by ESI-TOF-MS. The multiple charge mass envelopes shifted to those of the lower mass charge state by addition of 4 molar equiv. ZnCl2, suggesting that gamma-C1A-C1B preserves some higher order structure by the zinc folding. Moreover, the mass spectrum of the zinc-folded peptide in the presence of EDTA clearly showed that gamma-C1A-C1B coordinates exactly four atoms of zinc. This zinc stoichiometry is identical to that of native PKCgamma. Scatchard analysis of the zinc-folded peptide revealed two binding sites of distinctly different affinities (Kd=6.0 +/- 1.5 and 47.0 +/- 6.6 nM) comparable to those reported by Quest and Bell for the GST fusion protein of gamma-C1A-C1B prepared by DNA recombination. These results indicate that gamma-C1A-C1B serves as an effective surrogate for native PKCgamma for the study of the structural characteristics of the binding recognition event and the design, discovery, and development of new PKCgamma-selective modulators.
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Affiliation(s)
- H Fukuda
- Nihon PerSeptive Ltd., Tokyo, Japan
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Slater SJ, Taddeo FJ, Mazurek A, Stagliano BA, Milano SK, Kelly MB, Ho C, Stubbs CD. Inhibition of membrane lipid-independent protein kinase Calpha activity by phorbol esters, diacylglycerols, and bryostatin-1. J Biol Chem 1998; 273:23160-8. [PMID: 9722545 DOI: 10.1074/jbc.273.36.23160] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The activity of membrane-associated protein kinase C (PKC) has previously been shown to be regulated by two discrete high and low affinity binding regions for diacylglycerols and phorbol esters (Slater, S. J., Ho, C., Kelly, M. B., Larkin, J. D., Taddeo, F. J., Yeager, M. D., and Stubbs, C. D. (1996) J. Biol. Chem. 271, 4627-4631). PKC is also known to interact with both cytoskeletal and nuclear proteins; however, less is known concerning the mode of activation of this non-membrane form of PKC. By using the fluorescent phorbol ester, sapintoxin D (SAPD), PKCalpha, alone, was found to possess both low and high affinity phorbol ester-binding sites, showing that interaction with these sites does not require association with the membrane. Importantly, a fusion protein containing the isolated C1A/C1B (C1) domain of PKCalpha also bound SAPD with low and high affinity, indicating that the sites may be confined to this domain rather than residing elsewhere on the enzyme molecule. Both high and low affinity interactions with native PKCalpha were enhanced by protamine sulfate, which activates the enzyme without requiring Ca2+ or membrane lipids. However, this "non-membrane" PKC activity was inhibited by the phorbol ester 4beta-12-O-tetradecanoylphorbol-13-acetate (TPA) and also by the fluorescent analog, SAPD, opposite to its effect on membrane-associated PKCalpha. Bryostatin-1 and the soluble diacylglycerol, 1-oleoyl-2-acetylglycerol, both potent activators of membrane-associated PKC, also competed for both low and high affinity SAPD binding and inhibited protamine sulfate-induced activity. Furthermore, the inactive phorbol ester analog 4alpha-TPA (4alpha-12-O-tetradecanoylphorbol-13-acetate) also inhibited non-membrane-associated PKC. In keeping with these observations, although TPA could displace high affinity SAPD binding from both forms of the enzyme, 4alpha-TPA was only effective at displacing high affinity SAPD binding from non-membrane-associated PKC. 4alpha-TPA also displaced SAPD from the isolated C1 domain. These results show that although high and low affinity phorbol ester-binding sites are found on non-membrane-associated PKC, the phorbol ester binding properties change significantly upon association with membranes.
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Affiliation(s)
- S J Slater
- Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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Irie K, Oie K, Nakahara A, Yanai Y, Ohigashi H, Wender PA, Fukuda H, Konishi H, Kikkawa U. Molecular Basis for Protein Kinase C Isozyme-Selective Binding: The Synthesis, Folding, and Phorbol Ester Binding of the Cysteine-Rich Domains of All Protein Kinase C Isozymes. J Am Chem Soc 1998. [DOI: 10.1021/ja981087f] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kazuhiro Irie
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Kentaro Oie
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Akifumi Nakahara
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Yoshiaki Yanai
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Hajime Ohigashi
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Paul A. Wender
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Hiroyuki Fukuda
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Hiroaki Konishi
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Ushio Kikkawa
- Contribution from Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan, Department of Chemistry, Stanford University, Stanford, California 94305, Nihon PerSeptive Ltd., Roppongi, Minato-ku, Tokyo 106-0032, Japan, and Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
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Irie K, Yanai Y, Oie K, Ishizawa J, Nakagawa Y, Ohigashi H, Wender PA, Kikkawa U. Comparison of chemical characteristics of the first and the second cysteine-rich domains of protein kinase C gamma. Bioorg Med Chem 1997; 5:1725-37. [PMID: 9313873 DOI: 10.1016/s0968-0896(97)00116-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Protein kinase C (PKC) is a key enzyme family involved in cellular signal transduction. The binding of endogenous diacyl glycerol (DAG) to the cysteine-rich domain (CRD) of PKC is associated with normal cell signaling and function. In contrast, the binding of exogenous phorbol esters to the CRD of PKC is considered to be a key initiating event in tumor promotion. Conventional PKC isozymes (PKC alpha, beta I, beta II, and gamma) contain two CRDs, both of which are candidates for the phorbol ester binding site. In order to elucidate the binding requirements of phorbol esters and to obtain information on the phorbol ester binding site in native PKC gamma, several key chemical characteristics of the first and the second CRDs consisting of ca. 50 amino acids of rat PKC gamma (gamma-CRD1 and gamma-CRD2) were examined. In the presence of Zn2+ and phosphatidylserine (PS), both CRDs gave similar Kd values (65.3 nM for gamma-CRD1, 44.1 nM for gamma-CRD2) in phorbol 12,13-dibutyrate (PDBu) binding assays. In comparison, the binding affinity of PDBu for native rat PKC gamma was found to be 6.8 nM. Zn2+ was shown to play an important role in the folding and PDBu binding of both CRDs. A Zn(2+)-induced conformational change was observed for the first time by CD spectroscopic analysis of the complexed and uncomplexed CRDs. Relative to the pronounced Zn2+ effect, most divalent first row transition metal ions along with Ca2+, Mg2+, and Al3+ were ineffective in folding either CRD. Notably, however, Co2+ exhibited a gamma-CRD1-selective effect, suggesting that metal ions, not unlike extensively used organic probes, might also become effective tools for controlling isozyme selective activation of PKC. Moreover, group Ib (Cu2+ and Ag+) and group IIb element ions other than Zn2+ (Cd2+ and Hg2+) were found to abolish PDBu binding of both CRDs. Importantly, these inhibitory effects of Cu2+, Ag+, and Cd2+, and Hg2+ were also observed with native PKC gamma. These results indicate that recent reports on the modulation of conventional PKC by heavy metal ions could be explained by their coordination to the CRDs. While the similar affinities of gamma-CRD1 and gamma-CRD2 for PDBu suggest that either site qualifies as the PDBu binding site, new molecular probes of these CRD3 have now been identified that provide information on the preferred site. These novel ligands (5a and 5b) were synthesized by aza-Claisen rearrangement of (-)-N13-desmethyl-N13-allylindolactam-G (4). These compounds did not significantly affect the specific PDBu binding of gamma-CRD1 but did inhibit that of gamma-CRD2 with similar potency to (-)-indolactam-V. Moreover, these new probes did not significantly inhibit the PDBu binding of native PKC gamma. (-)-Indolactam-V itself bound almost equally to gamma-CRD1, gamma-CRD2, and native PKC gamma. These results suggest that the major PDBu binding site in native PKC gamma is the first CRD, not the second CRD, unlike the novel PKCs.
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Affiliation(s)
- K Irie
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Japan
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