title: Oncogenic function of SCCRO5/DCUN1D5 requires its Neddylation E3 activity and nuclear localization.
abstract: OBJECTIVE
  To determine mechanisms by which SCCRO5 (aka DCUN1D5) promotes oncogenesis.
  
  
  METHODS
  SCCRO5 mRNA and protein expression were assessed in 203 randomly selected primary cancer tissue samples, matched histologically normal tissues, and cell lines by use of real-time PCR and Western blot analysis. SCCRO5 overexpression was correlated with survival. The effect of SCCRO5 knockdown on viability was assessed in selected cancer cell lines. Structure-function studies were performed to determine the SCCRO5 residues required for binding to the neddylation components, for neddylation-promoting activity, and for transformation.
  
  
  RESULTS
  In oral and lung squamous cell carcinomas, SCCRO5 mRNA levels corresponded with protein levels and overexpression correlated with decreased disease-specific survival. Knockdown of SCCRO5 by RNAi resulted in a selective decrease in the viability of cancer cells with high endogenous levels, suggesting the presence of oncogene addiction. SCCRO5 promoted cullin neddylation while maintaining conserved reaction processivity paradigms involved in ubiquitin and ubiquitin-like protein conjugation, establishing it as a component of the neddylation E3. Neddylation activities in vitro required the potentiating of neddylation (PONY) domain but not the nuclear localization sequence (NLS) domain. In contrast, both the NLS domain and the PONY domain were required for transformation of NIH-3T3 cells.
  
  
  CONCLUSIONS
  Our data suggest that SCCRO5 has oncogenic potential that requires its function as a component of the neddylation E3. Neddylation activity and nuclear localization of SCCRO5 are important for its in vivo function.
authors.affiliation: Authors' Affiliations: Department of Surgery, Laboratory of Epithelial Cancer Biology and Departments of Epidemiology and Biostatistics and Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York.
authors.forename: Claire C
authors.initials: CC
authors.lastname: Bommeljé
authors.forename: Víola B
authors.initials: VB
authors.lastname: Weeda
authors.forename: Guochang
authors.initials: G
authors.lastname: Huang
authors.forename: Kushyup
authors.initials: K
authors.lastname: Shah
authors.forename: Sarina
authors.initials: S
authors.lastname: Bains
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Buss
authors.forename: Manish
authors.initials: M
authors.lastname: Shaha
authors.forename: Mithat
authors.initials: M
authors.lastname: Gönen
authors.forename: Ronald
authors.initials: R
authors.lastname: Ghossein
authors.forename: Suresh Y
authors.initials: SY
authors.lastname: Ramanathan
authors.forename: Bhuvanesh
authors.initials: B
authors.lastname: Singh
mesh_terms: D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000378:metabolism*; D044842:Cullin Proteins / Q000378:metabolism; D018450:Disease Progression; D015870:Gene Expression; D006801:Humans; D051379:Mice; D009369:Neoplasms / Q000235:genetics / Q000378:metabolism / Q000401:mortality; D015513:Oncogene Proteins / Q000235:genetics* / Q000378:metabolism*; D010453:Peptide Synthases / Q000235:genetics* / Q000378:metabolism*; D010641:Phenotype; D011485:Protein Binding; D021381:Protein Transport; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D014452:Ubiquitins / Q000378:metabolism
chemical_list: D044842:Cullin Proteins; D015513:Oncogene Proteins; D014452:Ubiquitins; D044767:Ubiquitin-Protein Ligases; C000591617:DCUN1D5 protein, human; D010453:Peptide Synthases