Abstract
Estrogen receptor-α (ERα) is a major therapeutic target of hormonal therapies in breast cancer, and its expression in tumors is predictive of clinical response. Protein levels of ERα are tightly controlled by the 26S proteasome; yet, how the clinical proteasome inhibitor, bortezomib, affects ERα regulation has not been studied. Bortezomib selectively inhibits the chymotrypsin-like activity of the proteasome. Unlike other laboratory proteasome inhibitors, bortezomib failed to stabilize ERα protein at a dose exceeding 90% inhibition of the chymotrypsin-like activity. Unexpectedly, however, chronic bortezomib exposure caused a reduction of ERα levels in multiple ER+ breast cancer cell lines. This response can be explained by the fact that bortezomib induced a dramatic decrease in ERα mRNA because of direct transcriptional inhibition and loss of RNA polymerase II recruitment on the ERα gene promoter. Bortezomib treatment resulted in promoter-specific changes in estrogen-induced gene transcription that related with occupancy of ERα and RNA polymerase II (PolII) on endogenous promoters. In addition, bortezomib inhibited estrogen-dependent growth in soft agar. These results reveal a novel link between proteasome activity and expression of ERα in breast cancer and uncover distinct roles of the chymotrypsin-like activity of the proteasome in the regulation of the ERα pathway.
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References
Adams BD, Furneaux H, White BA . (2007). The micro-ribonucleic acid (miRNA) miR-206 targets the human estrogen receptor-alpha (ERalpha) and represses ERalpha messenger RNA and protein expression in breast cancer cell lines. Mol Endocrinol 21: 1132–1147.
Alarid ET . (2006). Lives and times of nuclear receptors. Mol Endocrinol 20: 1972–1981.
Alarid ET, Bakopoulos N, Solodin N . (1999). Proteasome-mediated proteolysis of estrogen receptor: a novel component in autologous down-regulation. Mol Endocrinol 13: 1522–1534.
Bazzaro M, Lee MK, Zoso A, Stirling WL, Santillan A, Shih Ie M et al. (2006). Ubiquitin-proteasome system stress sensitizes ovarian cancer to proteasome inhibitor-induced apoptosis. Cancer Res 66: 3754–3763.
Bossola M, Muscaritoli M, Costelli P, Grieco G, Bonelli G, Pacelli F et al. (2003). Increased muscle proteasome activity correlates with disease severity in gastric cancer patients. Ann Surg 237: 384–389.
Cardoso F, Durbecq V, Laes JF, Badran B, Lagneaux L, Bex F et al. (2006). Bortezomib (PS-341, Velcade) increases the efficacy of trastuzumab (Herceptin) in HER-2-positive breast cancer cells in a synergistic manner. Mol Cancer Ther 5: 3042–3051.
Chen L, Madura K . (2005). Increased proteasome activity, ubiquitin-conjugating enzymes, and eEF1A translation factor detected in breast cancer tissue. Cancer Res 65: 5599–5606.
Chia S, Gradishar W, Mauriac L, Bines J, Amant F, Federico M et al. (2008). Double-blind, randomized placebo controlled trial of fulvestrant compared with exemestane after prior nonsteroidal aromatase inhibitor therapy in postmenopausal women with hormone receptor-positive, advanced breast cancer: results from EFECT. J Clin Oncol 26: 1664–1670.
Clarke RB, Howell A, Potten CS, Anderson E . (1997). Dissociation between steroid receptor expression and cell proliferation in the human breast. Cancer Res 57: 4987–4991.
Coates AS, Keshaviah A, Thurlimann B, Mouridsen H, Mauriac L, Forbes JF et al. (2007). Five years of letrozole compared with tamoxifen as initial adjuvant therapy for postmenopausal women with endocrine-responsive early breast cancer: update of study BIG 1–98. J Clin Oncol 25: 486–492.
Codony-Servat J, Tapia MA, Bosch M, Oliva C, Domingo-Domenech J, Mellado B et al. (2006). Differential cellular and molecular effects of bortezomib, a proteasome inhibitor, in human breast cancer cells. Mol Cancer Ther 5: 665–675.
Dauvois S, White R, Parker MG . (1993). The antiestrogen ICI 182780 disrupts estrogen receptor nucleocytoplasmic shuttling. J Cell Sci 106 (Pt 4): 1377–1388.
DeFriend DJ, Anderson E, Bell J, Wilks DP, West CM, Mansel RE et al. (1994). Effects of 4-hydroxytamoxifen and a novel pure antioestrogen (ICI 182780) on the clonogenic growth of human breast cancer cells in vitro. Br J Cancer 70: 204–211.
DeNardo DG, Cuba VL, Kim H, Wu K, Lee AV, Brown PH . (2007). Estrogen receptor DNA binding is not required for estrogen-induced breast cell growth. Mol Cell Endocrinol 277: 13–25.
Denger S, Reid G, Kos M, Flouriot G, Parsch D, Brand H et al. (2001). ERalpha gene expression in human primary osteoblasts: evidence for the expression of two receptor proteins. Mol Endocrinol 15: 2064–2077.
Dhasarathy A, Kajita M, Wade PA . (2007). The transcription factor snail mediates epithelial to mesenchymal transitions by repression of estrogen receptor-alpha. Mol Endocrinol 21: 2907–2918.
Dowsett M, Santner SJ, Santen RJ, Jeffcoate SL, Smith IE . (1985). Effective inhibition by low dose aminoglutethimide of peripheral aromatization in postmenopausal breast cancer patients. Br J Cancer 52: 31–35.
El Khissiin A, Leclercq G . (1999). Implication of proteasome in estrogen receptor degradation. FEBS Lett 448: 160–166.
Ellison-Zelski SJ, Solodin NM, Alarid ET . (2009). Repression of ESR1 through actions of estrogen receptor alpha and Sin3A at the proximal promoter. Mol Cell Biol 29: 4949–4958.
Engel RH, Brown JA, Von Roenn JH, O'Regan RM, Bergan R, Badve S et al. (2007). A phase II study of single agent bortezomib in patients with metastatic breast cancer: a single institution experience. Cancer Invest 25: 733–737.
Fabris G, Marchetti E, Marzola A, Bagni A, Querzoli P, Nenci I . (1987). Pathophysiology of estrogen receptors in mammary tissue by monoclonal antibodies. J Steroid Biochem 27: 171–176.
Fan M, Nakshatri H, Nephew KP . (2004). Inhibiting proteasomal proteolysis sustains estrogen receptor-alpha activation. Mol Endocrinol 18: 2603–2615.
Feng Y, Manka D, Wagner KU, Khan SA . (2007). Estrogen receptor-alpha expression in the mammary epithelium is required for ductal and alveolar morphogenesis in mice. Proc Natl Acad Sci USA 104: 14718–14723.
Fowler AM, Solodin NM, Valley CC, Alarid ET . (2006). Altered target gene regulation controlled by estrogen receptor-alpha concentration. Mol Endocrinol 20: 291–301.
Han Y, Yang L, Suarez-Saiz F, San-Marina S, Cui J, Minden MD . (2008). Wilms' tumor 1 suppressor gene mediates antiestrogen resistance via down-regulation of estrogen receptor-alpha expression in breast cancer cells. Mol Cancer Res 6: 1347–1355.
Harrell JC, Dye WW, Harvell DM, Pinto M, Jedlicka P, Sartorius CA et al. (2007). Estrogen insensitivity in a model of estrogen receptor positive breast cancer lymph node metastasis. Cancer Res 67: 10582–10591.
Heinemeyer W, Fischer M, Krimmer T, Stachon U, Wolf DH . (1997). The active sites of the eukaryotic 20 S proteasome and their involvement in subunit precursor processing. J Biol Chem 272: 25200–25209.
Hui R, Finney GL, Carroll JS, Lee CS, Musgrove EA, Sutherland RL . (2002). Constitutive overexpression of cyclin D1 but not cyclin E confers acute resistance to antiestrogens in T-47D breast cancer cells. Cancer Res 62: 6916–6923.
Jordan VC . (1976). Antiestrogenic and antitumor properties of tamoxifen in laboratory animals. Cancer Treat Rep 60: 1409–1419.
Khan SA, Sachdeva A, Naim S, Meguid MM, Marx W, Simon H et al. (1999). The normal breast epithelium of women with breast cancer displays an aberrant response to estradiol. Cancer Epidemiol Biomarkers Prev 8: 867–872.
Kisselev AF, Callard A, Goldberg AL . (2006). Importance of the different proteolytic sites of the proteasome and the efficacy of inhibitors varies with the protein substrate. J Biol Chem 281: 8582–8590.
Kondo N, Toyama T, Sugiura H, Fujii Y, Yamashita H . (2008). miR-206 expression is down-regulated in estrogen receptor alpha-positive human breast cancer. Cancer Res 68: 5004–5008.
Kos M, Reid G, Denger S, Gannon F . (2001). Minireview: genomic organization of the human ERalpha gene promoter region. Mol Endocrinol 15: 2057–2063.
Kumatori A, Tanaka K, Inamura N, Sone S, Ogura T, Matsumoto T et al. (1990). Abnormally high expression of proteasomes in human leukemic cells. Proc Natl Acad Sci USA 87: 7071–7075.
Lee S, Medina D, Tsimelzon A, Mohsin SK, Mao S, Wu Y et al. (2007). Alterations of gene expression in the development of early hyperplastic precursors of breast cancer. Am J Pathol 171: 252–262.
Lee S, Mohsin SK, Mao S, Hilsenbeck SG, Medina D, Allred DC . (2006). Hormones, receptors, and growth in hyperplastic enlarged lobular units: early potential precursors of breast cancer. Breast Cancer Res 8: R6.
Liedtke C, Broglio K, Moulder S, Hsu L, Kau SW, Symmans WF et al. (2009). Prognostic impact of discordance between triple-receptor measurements in primary and recurrent breast cancer. Ann Oncol (e-pub ahead of print).
Livak KJ, Schmittgen TD . (2001). Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) method. Methods 25: 402–408.
Lonard DM, Nawaz Z, Smith CL, O'Malley BW . (2000). The 26S proteasome is required for estrogen receptor-alpha and coactivator turnover and for efficient estrogen receptor-alpha transactivation. Mol Cell 5: 939–948.
Maki CG, Huibregtse JM, Howley PM . (1996). in vivo ubiquitination and proteasome-mediated degradation of p53(1). Cancer Res 56: 2649–2654.
Marx C, Yau C, Banwait S, Zhou Y, Scott GK, Hann B et al. (2007). Proteasome-regulated ERBB2 and estrogen receptor pathways in breast cancer. Mol Pharmacol 71: 1525–1534.
Metivier R, Penot G, Hubner MR, Reid G, Brand H, Kos M et al. (2003). Estrogen receptor-alpha directs ordered, cyclical, and combinatorial recruitment of cofactors on a natural target promoter. Cell 115: 751–763.
Nawaz Z, Lonard DM, Dennis AP, Smith CL, O'Malley BW . (1999). Proteasome-dependent degradation of the human estrogen receptor. Proc Natl Acad Sci USA 96: 1858–1862.
Nomura Y, Tashiro H, Shinozuka K . (1985). Changes of steroid hormone receptor content by chemotherapy and/or endocrine therapy in advanced breast cancer. Cancer 55: 546–551.
O'Donnell AJ, Macleod KG, Burns DJ, Smyth JF, Langdon SP . (2005). Estrogen receptor-alpha mediates gene expression changes and growth response in ovarian cancer cells exposed to estrogen. Endocr Relat Cancer 12: 851–866.
Oesterreich S, Zhang P, Guler RL, Sun X, Curran EM, Welshons WV et al. (2001). Re-expression of estrogen receptor alpha in estrogen receptor alpha-negative MCF-7 cells restores both estrogen and insulin-like growth factor-mediated signaling and growth. Cancer Res 61: 5771–5777.
Orlowski M, Wilk S . (1981). A multicatalytic protease complex from pituitary that forms enkephalin and enkephalin containing peptides. Biochem Biophys Res Commun 101: 814–822.
Pandey DP, Picard D . (2009). miR-22 inhibits estrogen signaling by directly targeting the estrogen receptor alpha mRNA. Mol Cell Biol 29: 3783–3790.
Parker MG . (1993). Action of ‘pure’ antiestrogens in inhibiting estrogen receptor action. Breast Cancer Res Treat 26: 131–137.
Qin C, Nguyen T, Stewart J, Samudio I, Burghardt R, Safe S . (2002). Estrogen up-regulation of p53 gene expression in MCF-7 breast cancer cells is mediated by calmodulin kinase IV-dependent activation of a nuclear factor kappaB/CCAAT-binding transcription factor-1 complex. Mol Endocrinol 16: 1793–1809.
Reid G, Hubner MR, Metivier R, Brand H, Denger S, Manu D et al. (2003). Cyclic, proteasome-mediated turnover of unliganded and liganded ERalpha on responsive promoters is an integral feature of estrogen signaling. Mol Cell 11: 695–707.
Richardson PG, Mitsiades C, Hideshima T, Anderson KC . (2006). Bortezomib: proteasome inhibition as an effective anticancer therapy. Annu Rev Med 57: 33–47.
Robertson JF, Llombart-Cussac A, Rolski J, Feltl D, Dewar J, Macpherson E et al. (2009). Activity of fulvestrant 500 mg versus anastrozole 1 mg as first-line treatment for advanced breast cancer: results from the FIRST study. J Clin Oncol 27: 4530–4535.
Rock KL, Gramm C, Rothstein L, Clark K, Stein R, Dick L et al. (1994). Inhibitors of the proteasome block the degradation of most cell proteins and the generation of peptides presented on MHC class I molecules. Cell 78: 761–771.
Shaaban AM, Sloane JP, West CR, Foster CS . (2002). Breast cancer risk in usual ductal hyperplasia is defined by estrogen receptor-alpha and Ki-67 expression. Am J Pathol 160: 597–604.
Shah MH, Young D, Kindler HL, Webb I, Kleiber B, Wright J et al. (2004). Phase II study of the proteasome inhibitor bortezomib (PS-341) in patients with metastatic neuroendocrine tumors. Clin Cancer Res 10: 6111–6118.
Shoker BS, Jarvis C, Clarke RB, Anderson E, Hewlett J, Davies MP et al. (1999). Estrogen receptor-positive proliferating cells in the normal and precancerous breast. Am J Pathol 155: 1811–1815.
Taggart CC, Greene CM, McElvaney NG, O'Neill S . (2002). Secretory leucoprotease inhibitor prevents lipopolysaccharide-induced IkappaBalpha degradation without affecting phosphorylation or ubiquitination. J Biol Chem 277: 33648–33653.
Teicher BA, Ara G, Herbst R, Palombella VJ, Adams J . (1999). The proteasome inhibitor PS-341 in cancer therapy. Clin Cancer Res 5: 2638–2645.
Valley CC, Metivier R, Solodin NM, Fowler AM, Mashek MT, Hill L et al. (2005). Differential regulation of estrogen-inducible proteolysis and transcription by the estrogen receptor alpha N terminus. Mol Cell Biol 25: 5417–5428.
Valley CC, Solodin NM, Powers GL, Ellison SJ, Alarid ET . (2008). Temporal variation in estrogen receptor-alpha protein turnover in the presence of estrogen. J Mol Endocrinol 40: 23–34.
Viale G, Regan MM, Maiorano E, Mastropasqua MG, Dell'Orto P, Rasmussen BB et al. (2007). Prognostic and predictive value of centrally reviewed expression of estrogen and progesterone receptors in a randomized trial comparing letrozole and tamoxifen adjuvant therapy for postmenopausal early breast cancer: BIG 1–98. J Clin Oncol 25: 3846–3852.
Wakeling AE, Dukes M, Bowler J . (1991). A potent specific pure antiestrogen with clinical potential. Cancer Res 51: 3867–3873.
Wang X, Belguise K, O'Neill CF, Sanchez-Morgan N, Romagnoli M, Eddy SF et al. (2009). RelB NF-kappaB represses estrogen receptor alpha expression via induction of the zinc finger protein Blimp1. Mol Cell Biol 29: 3832–3844.
Wijayaratne AL, McDonnell DP . (2001). The human estrogen receptor-alpha is a ubiquitinated protein whose stability is affected differentially by agonists, antagonists, and selective estrogen receptor modulators. J Biol Chem 276: 35684–35692.
Wong DJ, Nuyten DS, Regev A, Lin M, Adler AS, Segal E et al. (2008). Revealing targeted therapy for human cancer by gene module maps. Cancer Res 68: 369–378.
Xu H, Ju D, Jarois T, Xie Y . (2008). Diminished feedback regulation of proteasome expression and resistance to proteasome inhibitors in breast cancer cells. Breast Cancer Res Treat 107: 267–274.
Yang CH, Gonzalez-Angulo AM, Reuben JM, Booser DJ, Pusztai L, Krishnamurthy S et al. (2006). Bortezomib (VELCADE) in metastatic breast cancer: pharmacodynamics, biological effects, and prediction of clinical benefits. Ann Oncol 17: 813–817.
Yuan JS, Reed A, Chen F, Stewart Jr CN . (2006). Statistical analysis of real-time PCR data. BMC Bioinformatics 7: 85.
Acknowledgements
This work was supported by Grants NIH DK64034 (ETA), DAMD-17-02-1-0286 (AVL), T32CA009135 (GLP), T32GM08688 (GLP) and W81XWH-06-1-0714 (AJC). We thank Drs Shigeki Miyamoto and Michael Fritsch for reagents.
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Powers, G., Ellison-Zelski, S., Casa, A. et al. Proteasome inhibition represses ERα gene expression in ER+ cells: a new link between proteasome activity and estrogen signaling in breast cancer. Oncogene 29, 1509–1518 (2010). https://doi.org/10.1038/onc.2009.434
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DOI: https://doi.org/10.1038/onc.2009.434
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