Abstract
The oncogenic transcription factor c-MYC (MYC) is deregulated and often overexpressed in more than 50% of cancers. MYC deregulation is associated with poor prognosis and aggressive disease, suggesting that the development of therapeutic inhibitors targeting MYC would markedly impact patient outcome. MYC is highly regulated, with a protein and mRNA half-life of ~30 min. The most extensively studied pathway regulating MYC protein stability involves ubiquitylation and proteasomal degradation mediated by the E3-ligase, SCFFbxw7. Here we provide evidence for an SCFFbxw7-independent regulatory mechanism centred on the highly conserved lysine-52 (K52) within MYC Box I. This residue has been shown to be post-translationally modified by both ubiquitylation and SUMOylation, hinting at the interplay of post-translational modifications at this site and the importance of this residue. We demonstrate that mutation of K52 to arginine (R) renders the MYC protein more labile. Mechanistically, we show that the degradation pathway regulated by K52 is independent of the Cullin-RING ligase family of E3-ligases, which includes not only the canonical SCFFbxw7 but also other known MYC-targeting E3-ligases, such as SCFSkp2, SCFβTCRP, SCFFbxo28 and DCXTRUSS. Taken together, our data identify a novel regulatory pathway centred on K52 that may be exploited for the development of anti-MYC therapeutics.
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References
Dang CV . MYC on the path to cancer. Cell 2012; 149: 22–35.
Nesbit CE, Tersak JM, Prochownik EV . MYC oncogenes and human neoplastic disease. Oncogene 1999; 18: 3004–3016.
Meyer N, Penn LZ . Reflecting on 25 years with MYC. Nat Rev Cancer 2008; 8: 976–990.
Kalkat M, De Melo J, Hickman KA, Lourenco C, Redel C, Resetca D et al. MYC deregulation in primary human cancers. Genes (Basel) 2017; 8: 151.
Dang CV, O’Donnell KA, Zeller KI, Nguyen T, Osthus RC, Li F . The c-Myc target gene network. Semin Cancer Biol 2006; 16: 253–264.
Wolf E, Lin CY, Eilers M, Levens DL . Taming of the beast: shaping Myc-dependent amplification. Trends Cell Biol 2015; 25: 241–248.
Lin CY, Lovén J, Rahl PB, Paranal RM, Burge CB, Bradner JE et al. Transcriptional amplification in tumor cells with elevated c-Myc. Cell 2012; 151: 56–67.
Kress TR, Sabò A, Amati B . MYC: connecting selective transcriptional control to global RNA production. Nat Rev Cancer 2015; 15: 593–607.
McKeown MR, Bradner JE . Therapeutic strategies to inhibit MYC. Cold Spring Harb Perspect Med 2014; 4: a014266.
Gustafson WC, Weiss WA . Myc proteins as therapeutic targets. Oncogene 2010; 29: 1249–1259.
Prochownik EV, Vogt PK . Therapeutic Targeting of Myc. Genes Cancer 2010; 1: 650–659.
Fletcher S, Prochownik EV . Small-molecule inhibitors of the Myc oncoprotein. Biochim Biophys Acta 2015; 1849: 525–543.
Delmore JE, Issa GC, Lemieux ME, Rahl PB, Shi J, Jacobs HM et al. BET bromodomain inhibition as a therapeutic strategy to target c-Myc. Cell 2011; 146: 904–917.
Zuber J, Shi J, Wang E, Rappaport AR, Herrmann H, Sison EA et al. RNAi screen identifies Brd4 as a therapeutic target in acute myeloid leukaemia. Nature 2011; 478: 524–528.
Shu S, Lin CY, He HH, Witwicki RM, Tabassum DP, Roberts JM et al. Response and resistance to BET bromodomain inhibitors in triple-negative breast cancer. Nature 2016; 529 (7586): 413–417 (advance on: 1–24).
Tu WB, Helander S, Pilstål R, Hickman KA, Lourenco C, Jurisica I et al. Myc and its interactors take shape. Biochim Biophys Acta 2014; 1849: 469–483.
Wasylishen AR, Kalkat M, Kim SS, Pandyra A, Chan P-K, Oliveri S et al. MYC activity is negatively regulated by a C-terminal lysine cluster. Oncogene 2014; 33: 1066–1072.
Wasylishen AR, Chan-Seng-Yue M, Bros C, Dingar D, Tu WB, Kalkat M et al. MYC phosphorylation at novel regulatory regions suppresses transforming activity. Cancer Res 2013; 73: 6504–6515.
Yeh E, Cunningham M, Arnold H, Chasse D, Monteith T, Ivaldi G et al. A signalling pathway controlling c-Myc degradation that impacts oncogenic transformation of human cells. Nat Cell Biol 2004; 6: 308–318.
Grim JE, Gustafson MP, Hirata RK, Hagar AC, Swanger J, Welcker M et al. Isoform- and cell cycle-dependent substrate degradation by the Fbw7 ubiquitin ligase. J Cell Biol 2008; 181: 913–920.
Welcker M, Orian A, Jin J, Grim JE, Grim JA, Harper JW et al. The Fbw7 tumor suppressor regulates glycogen synthase kinase 3 phosphorylation-dependent c-Myc protein degradation. Proc Natl Acad Sci USA 2004; 101: 9085–9090.
Yada M, Hatakeyama S, Kamura T, Nishiyama M, Tsunematsu R, Imaki H et al. Phosphorylation-dependent degradation of c-Myc is mediated by the F-box protein Fbw7. EMBO J 2004; 23: 2116–2125.
Helander S, Montecchio M, Pilstål R, Su Y, Kuruvilla J, Elvén M et al. Pre-anchoring of Pin1 to unphosphorylated c-Myc in a fuzzy complex regulates c-Myc activity. Structure 2015; 23: 2267–2279.
Popov N, Schülein C, Jaenicke LA, Eilers M . Ubiquitylation of the amino terminus of Myc by SCF(β-TrCP) antagonizes SCF(Fbw7)-mediated turnover. Nat Cell Biol 2010; 12: 973–981.
Kim SY, Herbst A, Tworkowski KA, Salghetti SE, Tansey WP . Skp2 regulates Myc protein stability and activity. Mol Cell 2003; 11: 1177–1188.
von der Lehr N, Johansson S, Wu S, Bahram F, Castell A, Cetinkaya C et al. The F-Box protein Skp2 participates in c-Myc proteosomal degradation and acts as a cofactor for c-Myc-regulated transcription. Mol Cell 2003; 11: 1189–1200.
Inoue S, Hao Z, Elia AJ, Cescon D, Zhou L, Silvester J et al. Mule/Huwe1/Arf-BP1 suppresses Ras-driven tumorigenesis by preventing c-Myc/Miz1-mediated down-regulation of p21 and p15. Genes Dev 2013; 27: 1101–1114.
Zhao X, JI-T Heng, Guardavaccaro D, Jiang R, Pagano M, Guillemot F et al. The HECT-domain ubiquitin ligase Huwe1 controls neural differentiation and proliferation by destabilizing the N-Myc oncoprotein. Nat Cell Biol 2008; 10: 643–653.
Adhikary S, Marinoni F, Hock A, Hulleman E, Popov N, Beier R et al. The ubiquitin ligase HectH9 regulates transcriptional activation by Myc and is essential for tumor cell proliferation. Cell 2005; 123: 409–421.
Choi SH, Wright JB, Gerber SA, Cole MD . Myc protein is stabilized by suppression of a novel E3 ligase complex in cancer cells. Genes Dev 2010; 24: 1236–1241.
Hakem A, Bohgaki M, Lemmers B, Tai E, Salmena L, Matysiak-Zablocki E et al. Role of Pirh2 in mediating the regulation of p53 and c-Myc. PLoS Genet 2011; 7: e1002360.
Paul I, Ahmed SF, Bhowmik A, Deb S, Ghosh MK . The ubiquitin ligase CHIP regulates c-Myc stability and transcriptional activity. Oncogene 2013; 32: 1284–1295.
Cepeda D, Ng H-F, Sharifi HR, Mahmoudi S, Cerrato VS, Fredlund E et al. CDK-mediated activation of the SCF(FBXO) (28) ubiquitin ligase promotes MYC-driven transcription and tumourigenesis and predicts poor survival in breast cancer. EMBO Mol Med 2013; 5: 999–1018.
Chen Y, Zhou C, Ji W, Mei Z, Hu B, Zhang W et al. ELL targets c-Myc for proteasomal degradation and suppresses tumour growth. Nat Commun 2016; 7: 11057.
Chakraborty AA, Scuoppo C, Dey S, Thomas LR, Lorey SL, Lowe SW et al. A common functional consequence of tumor-derived mutations within c-MYC. Oncogene 2014; 34: 1–4.
Pulverer BJ, Fisher C, Vousden K, Littlewood T, Evan G, Woodgett JR . Site-specific modulation of c-Myc cotransformation by residues phosphorylated in vivo. Oncogene 1994; 9: 59–70.
Li LH, Nerlov C, Prendergast G, MacGregor D, Ziff EB . c-Myc represses transcription in vivo by a novel mechanism dependent on the initiator element and Myc box II. EMBO J 1994; 13: 4070–4079.
Zhang Q, Spears E, Boone DN, Li Z, Gregory MA, Hann SR . Domain-specific c-Myc ubiquitylation controls c-Myc transcriptional and apoptotic activity. Proc Natl Acad Sci USA 2013; 110: 978–983.
Kalkat M, Chan P-K, Wasylishen AR, Srikumar T, Kim SS, Ponzielli R et al. Identification of c-MYC SUMOylation by mass spectrometry. PLoS One 2014; 9: e115337.
Oster SK, Mao DYL, Kennedy J, Penn LZ . Functional analysis of the N-terminal domain of the Myc oncoprotein. Oncogene 2003; 22: 1998–2010.
Wasylishen AR, Stojanova A, Oliveri S, Rust AC, Schimmer AD, Penn LZ . New model systems provide insights into Myc-induced transformation. Oncogene 2011; 30: 3727–3734.
Topham C, Tighe A, Ly P, Bennett A, Sloss O, Nelson L et al. MYC is a major determinant of mitotic cell fate. Cancer Cell 2015; 28: 129–140.
Herbst A, Hemann MT, Tworkowski KA, Salghetti SE, Lowe SW, Tansey WP . A conserved element in Myc that negatively regulates its proapoptotic activity. EMBO Rep 2005; 6: 177–183.
McMahon SB, Van Buskirk HA, Dugan KA, Copeland TD, Cole MD . The novel ATM-related protein TRRAP is an essential cofactor for the c- Myc and E2F oncoproteins. Cell 1998; 94: 363–374.
Soucy TA, Smith PG, Milhollen MA, Berger AJ, Gavin JM, Adhikari S et al. An inhibitor of NEDD8-activating enzyme as a new approach to treat cancer. Nature 2009; 458: 732–736.
Ran FA, Hsu PD, Wright J, Agarwala V, Scott DA, Zhang F . Genome engineering using the CRISPR-Cas9 system. Nat Protoc 2013; 8: 2281–2308.
Rajagopalan H, Jallepalli PV, Rago C, Velculescu VE, Kinzler KW, Vogelstein B et al. Inactivation of hCDC4 can cause chromosomal instability. Nature 2004; 428: 77–81.
Diefenbacher ME, Chakraborty A, Blake SM, Mitter R, Popov N, Eilers M et al. Usp28 counteracts Fbw7 in intestinal homeostasis and cancer. Cancer Res 2015; 75: 1181–1186.
Rabellino A, Melegari M, Tompkins VS, Chen W, Van Ness BG, Teruya-Feldstein J et al. PIAS1 promotes lymphomagenesis through MYC upregulation. Cell Rep 2016; 15: 2266–2278.
González-Prieto R, Cuijpers S A. GG, Kumar R, Hendriks IA, Vertegaal ACOO . c-Myc is targeted to the proteasome for degradation in a SUMOylation-dependent manner, regulated by PIAS1, SENP7 and RNF4. Cell Cycle 2015; 14: 37–41.
Kim W, Bennett EJ, Huttlin EL, Guo A, Li J, Possemato A et al. Systematic and quantitative assessment of the ubiquitin-modified proteome. Mol Cell 2011; 44: 325–340.
Akhoondi S, Sun D, Von Der Lehr N, Apostolidou S, Klotz K, Maljukova A et al. FBXW7/hCDC4 is a general tumor suppressor in human cancer. Cancer Res 2007; 67: 9006–9012.
Campeau E, Ruhl VE, Rodier F, Smith CL, Rahmberg BL, Fuss JO et al. A versatile viral system for expression and depletion of proteins in mammalian cells. PLoS ONE 2009; 4: e6529.
Acknowledgements
We thank Dr Bert Vogelstein for the HCT116 cells (wt/Fbxw7−/−) and all members of the Penn lab and especially the technical support of Aaliya Tamachi and Natasha Vitkin. LZP holds the Tier 1 Canada Research Chair in Molecular Oncology. This work was also supported by the Canadian Institutes of Health Research (MOP275788).
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De Melo, J., Kim, S., Lourenco, C. et al. Lysine-52 stabilizes the MYC oncoprotein through an SCFFbxw7-independent mechanism. Oncogene 36, 6815–6822 (2017). https://doi.org/10.1038/onc.2017.268
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DOI: https://doi.org/10.1038/onc.2017.268
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