title: Specific expression of k63-linked ubiquitination of calmodulin-like protein 5 in breast cancer of premenopausal patients.
abstract: OBJECTIVE
  Posttranslational modifications such as ubiquitination regulate many functions of proteins by affecting their interaction with other molecules, their activity, and their subcellular localization. In cancer biology, the ubiquitin network has gained major interest. K63-linked ubiquitination has emerged as a posttranslational modification with functional consequences, as it acts in several processes such as protein trafficking, DNA repair, and inflammation. Moreover, k63-linked ubiquitination is involved in the regulation of carcinogenesis. Based on previous findings, the aim of this study was to evaluate the ubiquitination of CALML5 in breast cancer patients.
  
  
  METHODS
  The breast cancer cell lines SkBr3, MCF7, HCC1937, and BT474 as well as 23 tumor samples of patients with primary breast cancer and the normal adjacent breast tissue were analyzed by one-dimensional immunoblot.
  
  
  RESULTS
  Using specific antibodies against CALML5 and k63-linked ubiquitin, we demonstrate a k63-linked ubiquitination in the nuclear fraction of premenopausal breast cancer patients. K63-linked ubiquitination of CALML5 was found in breast cancer tissue, but not found in surrounding healthy tissue.
  
  
  CONCLUSIONS
  Our findings support the concept that ubiquitination of CALML5 in the nucleus is involved in the carcinogenesis of breast cancer in premenopausal women.
authors.affiliation: Department of Obstetrics and Gynecology, Centre for Integrated Oncology, University of Bonn, Bonn, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Debald
authors.forename: Frank Alexander
authors.initials: FA
authors.lastname: Schildberg
authors.forename: Andrea
authors.initials: A
authors.lastname: Linke
authors.forename: Klaus
authors.initials: K
authors.lastname: Walgenbach
authors.forename: Walther
authors.initials: W
authors.lastname: Kuhn
authors.forename: Gunther
authors.initials: G
authors.lastname: Hartmann
authors.forename: Gisela
authors.initials: G
authors.lastname: Walgenbach-Brünagel
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000378:metabolism; D005260:Female; D057809:HEK293 Cells; D006801:Humans; D015151:Immunoblotting; D008239:Lysine / Q000378:metabolism; D008875:Middle Aged; D017697:Premenopause / Q000378:metabolism; D014407:Tumor Cells, Cultured; D054875:Ubiquitination
chemical_list: C408467:CALML5 protein, human; D002135:Calcium-Binding Proteins; D008239:Lysine