title: Evaluation of kallikrein-related peptidase 5 expression and its significance for breast cancer patients: association with kallikrein-related peptidase 7 expression.
abstract: BACKGROUND
  Kallikrein-related peptidases (KLKs) have been proposed as potential cancer biomarkers. Contradictions in literature led us to clarify the role of KLK5 as a breast cancer predictor, as well as its association with KLK7 expression.
  
  
  METHODS
  Semi-quantitative RT-PCR detected KLKs 5 and 7 in 80 breast tissues, 74 neoplastic and 6 normal. Steroid hormone receptors were quantified in all samples. Associations between KLK5 status and clinicopathological variables, as well as disease-free survival (DFS) and overall survival (OS) of patients were analyzed.
  
  
  RESULTS
  Forty tumor tissues showed high KLK5 expression, which was significantly associated with estrogen receptor status. Significant co-expression of KLKs 5 and 7 was observed in the same cancer samples (p=0.02). Increased KLK5 expression was a statistically significant independent prognostic factor for DFS (p=0.009 univariate analysis and p=0.028 multivariate analysis) and OS of patients (p=0.014, univariate analysis).
  
  
  CONCLUSIONS
  Increased KLK5 expression can contribute to the prognosis of DFS and OS of breast cancer patients. KLKs 5 and 7 are co-expressed in breast cancer.
authors.affiliation: Department of Cellular Physiology, "G. Papanicolaou" Research Center of Oncology, Saint Savvas Hospital, 171 Alexandras Avenue, Athens 11522, Greece. talieri@agsavvas-hosp.gr
authors.forename: Maroulio
authors.initials: M
authors.lastname: Talieri
authors.forename: Marina
authors.initials: M
authors.lastname: Devetzi
authors.forename: Andreas
authors.initials: A
authors.lastname: Scorilas
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Prezas
authors.forename: Alexandros
authors.initials: A
authors.lastname: Ardavanis
authors.forename: Aikaterini
authors.initials: A
authors.lastname: Apostolaki
authors.forename: Andreas
authors.initials: A
authors.lastname: Karameris
mesh_terms: D000368:Aged; D001483:Base Sequence; D001943:Breast Neoplasms / Q000201:enzymology* / Q000473:pathology; D017931:DNA Primers; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D007610:Kallikreins / Q000378:metabolism*; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis
chemical_list: D017931:DNA Primers; D007527:Isoenzymes; D007610:Kallikreins