miR-122 Regulates p53/Akt Signalling and the Chemotherapy-Induced Apoptosis in Cutaneous T-Cell Lymphoma

Advanced cutaneous T-cell lymphoma (CTCL) is resistant to chemotherapy and presents a major area of medical need. In view of the known role of microRNAs (miRNAs) in the regulation of cellular signalling, we aimed to identify the functionally important miRNA species, which regulate apoptosis in CTCL. Using a recently established model in which apoptosis of CTCL cell lines is induced by Notch-1 inhibition by γ-secretase inhibitors (GSIs), we found that miR-122 was significantly increased in the apoptotic cells. miR-122 up-regulation was not specific for GSI-1 but was also seen during apoptosis induced by chemotherapies including doxorubicin and proteasome blockers (bortezomib, MG132). miR-122 was not expressed in quiescent T-cells, but was detectable in CTCL: in lesional skin in mycosis fungoides and in Sézary cells purified from peripheral blood. In situ hybridization results showed that miR-122 was expressed in the malignant T-cell infiltrate and increased in the advanced stage mycosis fungoides. Surprisingly, miR-122 overexpression decreased the sensitivity to the chemotherapy-induced apoptosis via a signaling circuit involving the activation of Akt and inhibition of p53. We have also shown that induction of miR-122 occurred via p53 and that p53 post-transcriptionally up-regulated miR-122. miR-122 is thus an amplifier of the antiapoptotic Akt/p53 circuit and it is conceivable that a pharmacological intervention in this pathway may provide basis for novel therapies for CTCL.

[1]  M. Ikawa,et al.  Cyclin G1 is involved in G2/M arrest in response to DNA damage and in growth control after damage recovery , 2001, Oncogene.

[2]  Nicola Pimpinelli,et al.  WHO-EORTC classification for cutaneous lymphomas. , 2005, Blood.

[3]  H. Macdonald,et al.  Notch signaling in the immune system. , 2010, Immunity.

[4]  J. Stenvang,et al.  The utility of LNA in microRNA-based cancer diagnostics and therapeutics. , 2008, Seminars in cancer biology.

[5]  A. Marrogi,et al.  p53 tumor suppressor gene mutations in transformed cutaneous T‐cell lymphoma: A study of 12 cases , 1999, Journal of cutaneous pathology.

[6]  K. Bhatia,et al.  Inhibition of Phosphatidylinositol 3′-Kinase/AKT Signaling Promotes Apoptosis of Primary Effusion Lymphoma Cells , 2005, Clinical Cancer Research.

[7]  Adam A. Margolin,et al.  NOTCH1 directly regulates c-MYC and activates a feed-forward-loop transcriptional network promoting leukemic cell growth , 2006, Proceedings of the National Academy of Sciences.

[8]  Heidi J. Peltier,et al.  Normalization of microRNA expression levels in quantitative RT-PCR assays: identification of suitable reference RNA targets in normal and cancerous human solid tissues. , 2008, RNA.

[9]  C. Croce,et al.  MiR-122/cyclin G1 interaction modulates p53 activity and affects doxorubicin sensitivity of human hepatocarcinoma cells. , 2009, Cancer research.

[10]  K. Thomsen,et al.  A continuous T-cell line from a patient with Sézary syndrome , 2004, Archives of Dermatological Research.

[11]  C. Felix,et al.  Overexpression of p53 protein in cutaneous T cell lymphoma: relationship to large cell transformation and disease progression. , 1998, The Journal of investigative dermatology.

[12]  Victoria Bolós,et al.  Notch signaling in development and cancer. , 2007, Endocrine reviews.

[13]  J. Sklar,et al.  TAN-1, the human homolog of the Drosophila Notch gene, is broken by chromosomal translocations in T lymphoblastic neoplasms , 1991, Cell.

[14]  S. Iida,et al.  Bortezomib‐induced apoptosis in mature T‐cell lymphoma cells partially depends on upregulation of Noxa and functional repression of Mcl‐1 , 2009, Cancer science.

[15]  Govind Bhagat,et al.  Mutational loss of PTEN induces resistance to NOTCH1 inhibition in T-cell leukemia , 2007, Nature Medicine.

[16]  Taous Khan,et al.  MicroRNAs: synthesis, mechanism, function, and recent clinical trials. , 2010, Biochimica et biophysica acta.

[17]  K. Somasundaram,et al.  Activated Notch1 Inhibits p53-Induced Apoptosis and Sustains Transformation by Human Papillomavirus Type 16 E6 and E7 Oncogenes through a PI3K-PKB/Akt-Dependent Pathway , 2003, Journal of Virology.

[18]  C. Korgaonkar,et al.  Cyclin G1 has growth inhibitory activity linked to the ARF-Mdm2-p53 and pRb tumor suppressor pathways. , 2003, Molecular cancer research : MCR.

[19]  H. Wulf,et al.  Bone marrow precursor of extranodal T-cell lymphoma. , 2003, Blood.

[20]  Ling Yin,et al.  Notch signaling: emerging molecular targets for cancer therapy. , 2010, Biochemical pharmacology.

[21]  R. Gniadecki,et al.  Potential involvement of Notch1 signalling in the pathogenesis of primary cutaneous CD30‐positive lymphoproliferative disorders , 2008, The British journal of dermatology.

[22]  Raphael Kopan,et al.  Notch-1 signalling requires ligand-induced proteolytic release of intracellular domain , 1998, Nature.

[23]  S. Kauppinen,et al.  Therapeutic Silencing of MicroRNA-122 in Primates with Chronic Hepatitis C Virus Infection , 2010, Science.

[24]  B. Nielsen,et al.  Robust one-day in situ hybridization protocol for detection of microRNAs in paraffin samples using LNA probes. , 2010, Methods.

[25]  D. Carvajal,et al.  Preclinical profile of a potent gamma-secretase inhibitor targeting notch signaling with in vivo efficacy and pharmacodynamic properties. , 2009, Cancer research.

[26]  A. Hauschild,et al.  Multicenter study of pegylated liposomal doxorubicin in patients with cutaneous T‐cell lymphoma , 2003, Cancer.

[27]  S. Thorgeirsson,et al.  Loss of miR-122 expression in liver cancer correlates with suppression of the hepatic phenotype and gain of metastatic properties , 2009, Oncogene.

[28]  S. Pileri,et al.  Gemcitabine treatment in pretreated cutaneous T-cell lymphoma: experience in 44 patients. , 2000, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[29]  V. Seshan,et al.  Pralatrexate Is Synergistic with the Proteasome Inhibitor Bortezomib in In vitro and In vivo Models of T-Cell Lymphoid Malignancies , 2010, Clinical Cancer Research.

[30]  R. Gniadecki,et al.  Notch1 as a potential therapeutic target in cutaneous T-cell lymphoma. , 2010, Blood.

[31]  E. Sontheimer,et al.  Origins and Mechanisms of miRNAs and siRNAs , 2009, Cell.

[32]  C. Croce,et al.  MicroRNA signatures in human cancers , 2006, Nature Reviews Cancer.

[33]  C. Croce,et al.  microRNAs: Master regulators as potential therapeutics in cancer. , 2011, Annual review of pharmacology and toxicology.

[34]  T. Shinohara,et al.  [In-vivo activation of the p53 pathway by small-molecule antagonists of MDM2]. , 2007, Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme.

[35]  Andrew P. Weng,et al.  Activating Mutations of NOTCH1 in Human T Cell Acute Lymphoblastic Leukemia , 2004, Science.

[36]  B. Kaczkowski,et al.  Reproducible pattern of microRNA in normal human skin , 2010, Experimental dermatology.

[37]  V. Ambros,et al.  An Extensive Class of Small RNAs in Caenorhabditis elegans , 2001, Science.

[38]  Chang-Zheng Chen,et al.  MicroRNAs as oncogenes and tumor suppressors. , 2005, The New England journal of medicine.

[39]  S. Kauppinen,et al.  LNA-mediated microRNA silencing in non-human primates , 2008, Nature.

[40]  B. Osborne,et al.  Notch signaling as a therapeutic target in cancer: a new approach to the development of cell fate modifying agents , 2003, Oncogene.

[41]  A. Gazdar,et al.  Human cutaneous T cell lymphoma and leukemia cell lines produce and respond to T cell growth factor , 1981, The Journal of experimental medicine.

[42]  V. Ambros.  The functions of animal microRNAs , 2004, Nature.

[43]  G. Courtois,et al.  Down-regulating constitutive activation of the NF-kappaB canonical pathway overcomes the resistance of cutaneous T-cell lymphoma to apoptosis. , 2006, Blood.

[44]  E. Robertson,et al.  IL-2- and IL-15-induced activation of the rapamycin-sensitive mTORC1 pathway in malignant CD4+ T lymphocytes. , 2008, Blood.

[45]  G. Dotto,et al.  Crosstalk of Notch with p53 and p63 in cancer growth control , 2009, Nature Reviews Cancer.

[46]  E. Jaffe,et al.  Mitogen requirements for the in vitro propagation of cutaneous T-cell lymphomas. , 1980, Blood.

[47]  C. Cho,et al.  Increased expression of cyclin G1 in leiomyoma compared with normal myometrium. , 2003, American journal of obstetrics and gynecology.

[48]  H. Macdonald,et al.  Deficient T cell fate specification in mice with an induced inactivation of Notch1. , 1999, Immunity.

[49]  A. Rademaker,et al.  The selective protein kinase C beta inhibitor enzastaurin induces apoptosis in cutaneous T-cell lymphoma cell lines through the AKT pathway. , 2006, The Journal of investigative dermatology.

[50]  B. Kaczkowski,et al.  Changes in oncomiR expression in CTCL cell lines during apoptosis induced by Notch inhibition. , 2010, Leukemia research.

[51]  Nicola Pimpinelli,et al.  Revisions to the staging and classification of mycosis fungoides and Sezary syndrome: a proposal of the International Society for Cutaneous Lymphomas (ISCL) and the cutaneous lymphoma task force of the European Organization of Research and Treatment of Cancer (EORTC). , 2007, Blood.