The Tumor Suppressor UCHL1 Forms a Complex with p53/MDM2/ARF to Promote p53 Signaling and Is Frequently Silenced in Nasopharyngeal Carcinoma

Purpose: Nasopharyngeal carcinoma is prevalent in southern China and Southeast Asia, with distinct geographic and ethnic distribution. One candidate susceptibility locus has been identified at 4p11-14, with the associated candidate gene(s) not identified yet. This study investigated the role of ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) in nasopharyngeal carcinoma pathogenesis. Experimental Design: UCHL1 expression and methylation were examined in nasopharyngeal carcinoma. Furthermore, the mechanism of its tumor-suppressive function was elucidated in nasopharyngeal carcinoma cells. Results: Through genomewide expression profiling, we identified UCHL1, a 4p14 gene normally expressed in normal upper respiratory tract tissues, being silenced in all nasopharyngeal carcinoma cell lines. Its silencing is mediated by CpG methylation because UCHL1 promoter methylation was detected in all silenced cell lines, and pharmacologic demethylation reactivated UCHL1 expression along with concomitant promoter demethylation. UCHL1 methylation was also frequently detected in primary tumors but only weakly detected in few normal nasopharyngeal tissues, indicating that the methylation-mediated silencing of UCHL1 is important in nasopharyngeal carcinoma pathogenesis. Ectopic UCHL1 expression dramatically inhibited the growth of nasopharyngeal carcinoma cells through promoting tumor cell apoptosis. We further found that UCHL1 formed a complex with p53/p14ARF/Mdm2 p53 binding protein homolog (mouse), MDM2 and activated the p53 signaling pathway. UCHL1 expression extended p53 and p14ARF protein half-life and shortened MDM2 protein half-life. Conclusions: These results indicate that UCHL1 could deubiquitinate p53 and p14ARF and ubiquitinate MDM2 for p53 stabilization to promote p53 signaling, thus involved in nasopharyngeal carcinoma pathogenesis, whereas it is frequently silenced in this tumor. Clin Cancer Res; 16(11); 2949–58. ©2010 AACR.

[1]  G. Evan,et al.  p53 — a Jack of all trades but master of none , 2009, Nature Reviews Cancer.

[2]  B. Seliger,et al.  Epigenetic control of the ubiquitin carboxyl terminal hydrolase 1 in renal cell carcinoma , 2009, Journal of Translational Medicine.

[3]  M. Kaminishi,et al.  The presence of aberrant DNA methylation in noncancerous esophageal mucosae in association with smoking history , 2009, Cancer.

[4]  M. Lung,et al.  Epigenetic disruption of interferon-γ response through silencing the tumor suppressor interferon regulatory factor 8 in nasopharyngeal, esophageal and multiple other carcinomas , 2008, Oncogene.

[5]  Kenji Hibi,et al.  PGP9.5 methylation as a marker for metastatic colorectal cancer. , 2008, Anticancer research.

[6]  D. Sidransky,et al.  The role of PGP9.5 as a tumor suppressor gene in human cancer , 2008, International journal of cancer.

[7]  Jun Yu,et al.  Epigenetic identification of ubiquitin carboxyl‐terminal hydrolase L1 as a functional tumor suppressor and biomarker for hepatocellular carcinoma and other digestive tumors , 2008, Hepatology.

[8]  N. Seki,et al.  CpG hypermethylation of the UCHL1 gene promoter is associated with pathogenesis and poor prognosis in renal cell carcinoma. , 2008, The Journal of urology.

[9]  H. Puthalakath,et al.  Ubiquitylation and cancer development. , 2008, Current cancer drug targets.

[10]  S. Tsao,et al.  Latent membrane protein 1 of Epstein-Barr virus regulates p53 phosphorylation through MAP kinases. , 2007, Cancer letters.

[11]  YoichiTakami,et al.  Ubiquitin Carboxyl-Terminal Hydrolase L1, a Novel Deubiquitinating Enzyme in the Vasculature, Attenuates NF-κB Activation , 2007 .

[12]  T. Ogihara,et al.  Ubiquitin Carboxyl-Terminal Hydrolase L1, a Novel Deubiquitinating Enzyme in the Vasculature, Attenuates NF-&kgr;B Activation , 2007, Arteriosclerosis, thrombosis, and vascular biology.

[13]  G. Srivastava,et al.  The tumor suppressor Wnt inhibitory factor 1 is frequently methylated in nasopharyngeal and esophageal carcinomas , 2007, Laboratory Investigation.

[14]  C. Mervis,et al.  Rearrangements of the Williams–Beuren syndrome locus: molecular basis and implications for speech and language development , 2007, Expert Reviews in Molecular Medicine.

[15]  Q. Tao,et al.  Nasopharyngeal carcinoma: molecular pathogenesis and therapeutic developments , 2007, Expert Reviews in Molecular Medicine.

[16]  P. Lansbury,et al.  Reversible Monoubiquitination Regulates the Parkinson Disease-associated Ubiquitin Hydrolase UCH-L1*♦ , 2007, Journal of Biological Chemistry.

[17]  Peter A. Jones,et al.  The Epigenomics of Cancer , 2007, Cell.

[18]  J. Califano,et al.  The major 8p22 tumor suppressor DLC1 is frequently silenced by methylation in both endemic and sporadic nasopharyngeal, esophageal, and cervical carcinomas, and inhibits tumor cell colony formation , 2007, Oncogene.

[19]  T. Ushijima,et al.  Silencing of the UCHL1 gene in human colorectal and ovarian cancers , 2006, International journal of cancer.

[20]  Dong Sun Kim,et al.  Hypomethylation of the protein gene product 9.5 promoter region in gallbladder cancer and its relationship with clinicopathological features , 2006, Cancer science.

[21]  D. Sidransky,et al.  PGP9.5 methylation in diffuse-type gastric cancer. , 2006, Cancer research.

[22]  P. Walker,et al.  Oxidative stress regulated expression of Ubiquitin Carboxyl-terminal Hydrolase-L1: Role in cell survival , 2006, Apoptosis.

[23]  T. Putti,et al.  Functional epigenetics identifies a protocadherin PCDH10 as a candidate tumor suppressor for nasopharyngeal, esophageal and multiple other carcinomas with frequent methylation , 2006, Oncogene.

[24]  Wei Gu,et al.  p53 ubiquitination: Mdm2 and beyond. , 2006, Molecular cell.

[25]  H. Qin,et al.  A functional variant in the transcriptional regulatory region of gene LOC344967 cosegregates with disease phenotype in familial nasopharyngeal carcinoma. , 2006, Cancer research.

[26]  K. Wada,et al.  Ubiquitin C-terminal hydrolase L1 regulates the morphology of neural progenitor cells and modulates their differentiation , 2006, Journal of Cell Science.

[27]  Qian Tao,et al.  The Stress-Responsive Gene GADD45G Is a Functional Tumor Suppressor, with Its Response to Environmental Stresses Frequently Disrupted Epigenetically in Multiple Tumors , 2005, Clinical Cancer Research.

[28]  Michael McClelland,et al.  Survey of differentially methylated promoters in prostate cancer cell lines. , 2005, Neoplasia.

[29]  Jun Qin,et al.  ARF-BP1/Mule Is a Critical Mediator of the ARF Tumor Suppressor , 2005, Cell.

[30]  B. Dörken,et al.  Loss of p21 disrupts p14ARF-induced G1 cell cycle arrest but augments p14ARF-induced apoptosis in human carcinoma cells , 2005, Oncogene.

[31]  Yoichi Tanaka,et al.  PGP9.5 promoter methylation is an independent prognostic factor for esophageal squamous cell carcinoma. , 2005, Cancer research.

[32]  Mei-Ling Kuo,et al.  N-terminal polyubiquitination and degradation of the Arf tumor suppressor. , 2004, Genes & development.

[33]  Qian Tao,et al.  The candidate tumor suppressor gene BLU, located at the commonly deleted region 3p21.3, is an E2F-regulated, stress-responsive gene and inactivated by both epigenetic and genetic mechanisms in nasopharyngeal carcinoma , 2004, Oncogene.

[34]  Yili Yang,et al.  Regulating the p53 system through ubiquitination , 2004, Oncogene.

[35]  U. Knippschild,et al.  Posttranslational modification of MDM2. , 2003, Molecular cancer research : MCR.

[36]  Hiroshi Nakayama,et al.  PGP9.5 overexpression in esophageal squamous cell carcinoma. , 2003, Hepato-gastroenterology.

[37]  Yi Zeng,et al.  Familial nasopharyngeal carcinoma. , 2002, Seminars in cancer biology.

[38]  P. Lansbury,et al.  The UCH-L1 Gene Encodes Two Opposing Enzymatic Activities that Affect α-Synuclein Degradation and Parkinson's Disease Susceptibility , 2002, Cell.

[39]  Q. Tao,et al.  Defective de novo methylation of viral and cellular DNA sequences in ICF syndrome cells. , 2002, Human molecular genetics.

[40]  Yan Fang,et al.  Genome-wide scan for familial nasopharyngeal carcinoma reveals evidence of linkage to chromosome 4 , 2002, Nature Genetics.

[41]  S. Tsao,et al.  Establishment of two immortalized nasopharyngeal epithelial cell lines using SV40 large T and HPV16E6/E7 viral oncogenes. , 2002, Biochimica et biophysica acta.

[42]  J. Jen,et al.  Interaction and colocalization of PGP9.5 with JAB1 and p27Kip1 , 2002, Oncogene.

[43]  Matty P. Weijenberg,et al.  A genomic screen for genes upregulated by demethylation and histone deacetylase inhibition in human colorectal cancer , 2002, Nature Genetics.

[44]  A. Bird.  DNA methylation patterns and epigenetic memory. , 2002, Genes & development.

[45]  A. Knudson,et al.  Two genetic hits (more or less) to cancer , 2001, Nature Reviews Cancer.

[46]  A. Nakao,et al.  PGP9.5 as a prognostic factor in pancreatic cancer. , 2000, Clinical cancer research : an official journal of the American Association for Cancer Research.

[47]  D. Lane,et al.  An N-terminal p14ARF peptide blocks Mdm2-dependent ubiquitination in vitro and can activate p53 in vivo , 2000, Oncogene.

[48]  Q. Tao,et al.  Methylation status of the Epstein-Barr virus major latent promoter C in iatrogenic B cell lymphoproliferative disease. Application of PCR-based analysis. , 1999, The American journal of pathology.

[49]  J. Herman,et al.  Synergy of demethylation and histone deacetylase inhibition in the re-expression of genes silenced in cancer , 1999, Nature Genetics.

[50]  Yue Xiong,et al.  ARF Promotes MDM2 Degradation and Stabilizes p53: ARF-INK4a Locus Deletion Impairs Both the Rb and p53 Tumor Suppression Pathways , 1998, Cell.

[51]  N. Colburn,et al.  An infrequent point mutation of the p53 gene in human nasopharyngeal carcinoma. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[52]  Pelayo Vilar,et al.  Nasopharyngeal Carcinoma , 1966 .

[53]  H. Maruyama,et al.  Functional , 2020, Congress of Neurological Surgeons Essent.