Metastasized malignant melanoma has a poor prognosis because of its intrinsic resistance to chemotherapy and radiotherapy. The central role in the melanoma transcriptional network has the transcription factor MITF (microphthalmia-associated transcription factor). It has been shown recently that the expression of MITF and some of its target genes require the SWI/SNF chromatin remodeling complex. Here we demonstrate that survival of melanoma cells requires functional SWI/SNF complex not only by supporting expression of MITF and its targets and but also by activating expression of prosurvival proteins not directly regulated by MITF. Microarray analysis revealed that besides the MITF-driven genes, expression of proteins like osteopontin, IGF1, TGFß2 and survivin, the factors known to be generally associated with progression of tumors and the antiapoptotic properties, were reduced in acute BRG1-depleted 501mel cells. Western blots and RT-PCR confirmed the microarray findings. These proteins have been verified to be expressed independently of MITF, because MITF depletion did not impair their expression. Because these genes are not regulated by MITF, the data suggests that loss of BRG1-based SWI/SNF complexes negatively affects survival pathways beyond the MITF cascade. Immunohistochemistry showed high expression of both BRM and BRG1 in primary melanomas. Exogenous CDK2, osteopontin, or IGF1 each alone partly relieved the block of proliferation imposed by BRG1 depletion, implicating that more factors, besides the MITF target genes, are involved in melanoma cell survival. Together these results demonstrate an essential role of SWI/SNF for the expression of MITF-dependent and MITF-independent prosurvival factors in melanoma cells and suggest that SWI/SNF may be a potential and effective target in melanoma therapy.

Laboratory of Transcription and Cell Signaling Institute of Medical Biochemistry and Laboratory Diagnostics 1st Faculty of Medicine Charles University Prague Prague Czech Republic

Zobrazit více v PubMed

Chin L, Garraway LA, Fisher DE (2006) Malignant melanoma: genetics and therapeutics in the genomic era. Genes Dev 20: 2149–2182. PubMed

Miller AJ, Mihm MC Jr (2006) Melanoma. N Engl J Med 355: 51–65. PubMed

Goding CR (2000) Mitf from neural crest to melanoma: signal transduction and transcription in the melanocyte lineage. Genes Dev 14: 1712–1728. PubMed

Levy C, Khaled M, Fisher DE (2006) MITF: master regulator of melanocyte development and melanoma oncogene. Trends Mol Med 12: 406–414. PubMed

Vachtenheim J, Borovansky J (2010) “Transcription physiology” of pigment formation in melanocytes: central role of MITF. Exp Dermatol 19: 617–627. PubMed

Du J, Widlund HR, Horstmann MA, Ramaswamy S, Ross K, et al. (2004) Critical role of CDK2 for melanoma growth linked to its melanocyte-specific transcriptional regulation by MITF. Cancer Cell 6: 565–576. PubMed

Carreira S, Goodall J, Aksan I, La Rocca SA, Galibert MD, et al. (2005) Mitf cooperates with Rb1 and activates p21Cip1 expression to regulate cell cycle progression. Nature 433: 764–769. PubMed

McGill GG, Horstmann M, Widlund HR, Du J, Motyckova G, et al. (2002) Bcl2 regulation by the melanocyte master regulator Mitf modulates lineage survival and melanoma cell viability. Cell 109: 707–718. PubMed

Dynek JN, Chan SM, Liu J, Zha J, Fairbrother WJ, et al. (2008) Microphthalmia-associated transcription factor is a critical transcriptional regulator of melanoma inhibitor of apoptosis in melanomas. Cancer Res 68: 3124–3132. PubMed

Carreira S, Goodall J, Denat L, Rodriguez M, Nuciforo P, et al. (2006) Mitf regulation of Dia1 controls melanoma proliferation and invasiveness. Genes Dev 20: 3426–3439. PubMed PMC

Goodall J, Carreira S, Denat L, Kobi D, Davidson I, et al. (2008) Brn-2 represses microphthalmia-associated transcription factor expression and marks a distinct subpopulation of microphthalmia-associated transcription factor-negative melanoma cells. Cancer Res 68: 7788–7794. PubMed

Roberts CW, Orkin SH (2004) The SWI/SNF complex–chromatin and cancer. Nat Rev Cancer 4: 133–142. PubMed

Halliday GM, Bock VL, Moloney FJ, Lyons JG (2009) SWI/SNF: a chromatin-remodelling complex with a role in carcinogenesis. Int J Biochem Cell Biol 41: 725–728. PubMed

Reisman D, Glaros S, Thompson EA (2009) The SWI/SNF complex and cancer. Oncogene 28: 1653–1668. PubMed

Versteege I, Sevenet N, Lange J, Rousseau-Merck MF, Ambros P, et al. (1998) Truncating mutations of hSNF5/INI1 in aggressive paediatric cancer. Nature 394: 203–206. PubMed

Medina PP, Romero OA, Kohno T, Montuenga LM, Pio R, et al. (2008) Frequent BRG1/SMARCA4-inactivating mutations in human lung cancer cell lines. Hum Mutat 29: 617–622. PubMed

Glaros S, Cirrincione GM, Muchardt C, Kleer CG, Michael CW, et al. (2007) The reversible epigenetic silencing of BRM: implications for clinical targeted therapy. Oncogene 26: 7058–7066. PubMed

Reisman DN, Sciarrotta J, Wang W, Funkhouser WK, Weissman BE (2003) Loss of BRG1/BRM in human lung cancer cell lines and primary lung cancers: correlation with poor prognosis. Cancer Res 63: 560–566. PubMed

Fukuoka J, Fujii T, Shih JH, Dracheva T, Meerzaman D, et al. (2004) Chromatin remodeling factors and BRM/BRG1 expression as prognostic indicators in non-small cell lung cancer. Clin Cancer Res 10: 4314–4324. PubMed

Dunaief JL, Strober BE, Guha S, Khavari PA, Alin K, et al. (1994) The retinoblastoma protein and BRG1 form a complex and cooperate to induce cell cycle arrest. Cell 79: 119–130. PubMed

Bartlett C, Orvis TJ, Rosson GS, Weissman BE (2011) BRG1 mutations found in human cancer cell lines inactivate Rb-mediated cell-cycle arrest. J Cell Physiol 226: 1989–1997. PubMed PMC

Sentani K, Oue N, Kondo H, Kuraoka K, Motoshita J, et al. (2001) Increased expression but not genetic alteration of BRG1, a component of the SWI/SNF complex, is associated with the advanced stage of human gastric carcinomas. Pathobiology 69: 315–320. PubMed

Sun A, Tawfik O, Gayed B, Thrasher JB, Hoestje S, et al. (2007) Aberrant expression of SWI/SNF catalytic subunits BRG1/BRM is associated with tumor development and increased invasiveness in prostate cancers. Prostate 67: 203–213. PubMed

de la Serna I, Ohkawa Y, Higashi C, Dutta C, Osias J, et al. (2006) The microphthalmia-associated transcription factor requires SWI/SNF enzymes to activate melanocyte-specific genes. J Biol Chem 281: 20233–20241. PubMed

Keenen B, Qi H, Saladi SV, Yeung M, de lS I (2010) Heterogeneous SWI/SNF chromatin remodeling complexes promote expression of microphthalmia-associated transcription factor target genes in melanoma. Oncogene 29: 81–92. PubMed PMC

Vachtenheim J, Ondrusova L, Borovansky J (2010) SWI/SNF chromatin remodeling complex is critical for the expression of microphthalmia-associated transcription factor in melanoma cells. Biochem Biophys Res Commun 392: 454–459. PubMed

Saladi SV, Marathe H, de lS I (2010) SWItching on the transcriptional circuitry in melanoma. Epigenetics 5: 469–475. PubMed PMC

Lin H, Wong RP, Martinka M, Li G (2010) BRG1 expression is increased in human cutaneous melanoma. Br J Dermatol 163: 502–510. PubMed

Saladi SV, Keenen B, Marathe HG, Qi H, Chin KV, et al. (2010) Modulation of extracellular matrix/adhesion molecule expression by BRG1 is associated with increased melanoma invasiveness. Mol Cancer 9: 280. PubMed PMC

Liu T, Brouha B, Grossman D (2004) Rapid induction of mitochondrial events and caspase-independent apoptosis in Survivin-targeted melanoma cells. Oncogene 23: 39–48. PubMed PMC

Busca R, Berra E, Gaggioli C, Khaled M, Bille K, et al. (2005) Hypoxia-inducible factor 1{alpha} is a new target of microphthalmia-associated transcription factor (MITF) in melanoma cells. J Cell Biol 170: 49–59. PubMed PMC

McGill GG, Haq R, Nishimura EK, Fisher DE (2006) c-Met expression is regulated by Mitf in the melanocyte lineage. J Biol Chem 281: 10365–10373. PubMed

Vachtenheim J, Novotna H, Ghanem G (2001) Transcriptional repression of the microphthalmia gene in melanoma cells correlates with the unresponsiveness of target genes to ectopic microphthalmia-associated transcription factor. J Invest Dermatol 117: 1505–1511. PubMed

Zhou Y, Dai DL, Martinka M, Su M, Zhang Y, et al. (2005) Osteopontin expression correlates with melanoma invasion. J Invest Dermatol 124: 1044–1052. PubMed

Hilmi C, Larribere L, Giuliano S, Bille K, Ortonne JP, et al. (2008) IGF1 promotes resistance to apoptosis in melanoma cells through an increased expression of BCL2, BCL-X(L), and survivin. J Invest Dermatol 128: 1499–1505. PubMed

Javelaud D, Alexaki VI, Mauviel A (2008) Transforming growth factor-beta in cutaneous melanoma. Pigment Cell Melanoma Res 21: 123–132. PubMed

Pierrat MJ, Marsaud V, Mauviel A, Javelaud D (2012) Expression of Microphtalmia-Associated Transcription Factor (MITF), which is Critical for Melanoma Progression, is Inhibited by both Transcription Factor GLI2 and Transforming Growth Factor-beta. J Biol Chem. PubMed PMC

Zhang C, Zhang F, Tsan R, Fidler IJ (2009) Transforming growth factor-beta2 is a molecular determinant for site-specific melanoma metastasis in the brain. Cancer Res 69: 828–835. PubMed PMC

Peltonen S, Hentula M, Hagg P, Yla-Outinen H, Tuukkanen J, et al. (1999) A novel component of epidermal cell-matrix and cell-cell contacts: transmembrane protein type XIII collagen. J Invest Dermatol 113: 635–642. PubMed

Das S, Harris LG, Metge BJ, Liu S, Riker AI, et al.. (2009) The hedgehog pathway transcription factor, GLI1 promotes malignant behavior of cancer cells by upregulating osteopontin. J Biol Chem. PubMed PMC

Vachtenheim J, Drdova B (2004) A dominant negative mutant of microphthalmia transcription factor (MITF) lacking two transactivation domains suppresses transcription mediated by wild type MITF and a hyperactive MITF derivative. Pigment Cell Res 17: 43–50. PubMed

Xu Y, Zhang J, Chen X (2007) The activity of p53 is differentially regulated by Brm- and Brg1-containing SWI/SNF chromatin remodeling complexes. J Biol Chem 282: 37429–37435. PubMed

Flowers S, Nagl NG Jr, Beck GR Jr, Moran E (2009) Antagonistic roles for BRM and BRG1 SWI/SNF complexes in differentiation. J Biol Chem 284: 10067–10075. PubMed PMC

Bourgo RJ, Siddiqui H, Fox S, Solomon D, Sansam CG, et al. (2009) SWI/SNF deficiency results in aberrant chromatin organization, mitotic failure, and diminished proliferative capacity. Mol Biol Cell 20 3192–3199. PubMed PMC

Strobeck MW, Reisman DN, Gunawardena RW, Betz BL, Angus SP, et al. (2002) Compensation of BRG-1 function by Brm: insight into the role of the core SWI-SNF subunits in retinoblastoma tumor suppressor signaling. J Biol Chem 277: 4782–4789. PubMed

Bandyopadhyay D, Curry JL, Lin Q, Richards HW, Chen D, et al. (2007) Dynamic assembly of chromatin complexes during cellular senescence: implications for the growth arrest of human melanocytic nevi. Aging Cell 6: 577–591. PubMed PMC

Shen H, Powers N, Saini N, Comstock CE, Sharma A, et al. (2008) The SWI/SNF ATPase Brm is a gatekeeper of proliferative control in prostate cancer. Cancer Res 68: 10154–10162. PubMed PMC

Yamamichi N, Inada K, Ichinose M, Yamamichi-Nishina M, Mizutani T, et al. (2007) Frequent loss of Brm expression in gastric cancer correlates with histologic features and differentiation state. Cancer Res 67: 10727–10735. PubMed

Becker TM, Haferkamp S, Dijkstra MK, Scurr LL, Frausto M, et al. (2009) The chromatin remodelling factor BRG1 is a novel binding partner of the tumor suppressor p16INK4a. Mol Cancer 8: 4. PubMed PMC

Kido K, Sumimoto H, Asada S, Okada SM, Yaguchi T, et al. (2009) Simultaneous suppression of MITF and BRAF V600E enhanced inhibition of melanoma cell proliferation. Cancer Sci 100: 1863–1869. PubMed PMC

Vaisanen T, Vaisanen MR, Autio-Harmainen H, Pihlajaniemi T (2005) Type XIII collagen expression is induced during malignant transformation in various epithelial and mesenchymal tumours. J Pathol 207: 324–335. PubMed

Ohanna M, Giuliano S, Bonet C, Imbert V, Hofman V, et al. (2011) Senescent cells develop a PARP-1 and nuclear factor-{kappa}B-associated secretome (PNAS). Genes Dev 25: 1245–1261. PubMed PMC

Giuliano S, Cheli Y, Ohanna M, Bonet C, Beuret L, et al. (2010) Microphthalmia-associated transcription factor controls the DNA damage response and a lineage-specific senescence program in melanomas. Cancer Res 70: 3813–3822. PubMed

Stecca B, Mas C, Clement V, Zbinden M, Correa R, et al. (2007) Melanomas require HEDGEHOG-GLI signaling regulated by interactions between GLI1 and the RAS-MEK/AKT pathways. Proc Natl Acad Sci U S A 104: 5895–5900. PubMed PMC

Hodis E, Watson IR, Kryukov GV, Arold ST, Imielinski M, et al. (2012) A landscape of driver mutations in melanoma. Cell 150: 251–263. PubMed PMC

Watanabe H, Mizutani T, Haraguchi T, Yamamichi N, Minoguchi S, et al. (2006) SWI/SNF complex is essential for NRSF-mediated suppression of neuronal genes in human nonsmall cell lung carcinoma cell lines. Oncogene 25: 470–479. PubMed

Inducibly decreased MITF levels do not affect proliferation and phenotype switching but reduce differentiation of melanoma cells

Survivin, a novel target of the Hedgehog/GLI signaling pathway in human tumor cells