title: An increase in N-Ras expression is associated with development of hormone refractory prostate cancer in a subset of patients.
abstract: Protein expression of H, K and N-Ras was assessed in hormone sensitive and hormone refractory prostate tumour pairs from 61 patients by immunohistochemistry. Expression of H-Ras and K- Ras was not associated with any known clinical parameters. In contrast an increase in N-Ras membrane expression in the transition from hormone sensitive to hormone refractory prostate cancer was associated with shorter time to relapse (p=0.01) and shorter disease specific survival (p=0.008). In addition, patients with an increase in N-Ras membrane expression had lower levels of PSA at relapse (p=0.02) and expression correlated with phosphorylated MAP kinase (p=0.010) and proliferation index (Ki67, p=0.02). These results suggest that in a subgroup patients N-Ras expression is associated with development of hormone refractory prostate cancer via activation of the MAP kinase cascade.
authors.affiliation: University Department of Surgery, Division of Cancer Sciences and Molecular Pathology, Glasgow Royal Infirmary, Glasgow, UK.
authors.forename: Pamela
authors.initials: P
authors.lastname: Traynor
authors.forename: Liane M
authors.initials: LM
authors.lastname: McGlynn
authors.forename: Rono
authors.initials: R
authors.lastname: Mukhergee
authors.forename: Samuel J S
authors.initials: SJ
authors.lastname: Grimsley
authors.forename: John M S
authors.initials: JM
authors.lastname: Bartlett
authors.forename: Joanne
authors.initials: J
authors.lastname: Edwards
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015153:Blotting, Western; D006801:Humans; D007150:Immunohistochemistry; D020935:MAP Kinase Signaling System; D008297:Male; D009376:Neoplasms, Hormone-Dependent / Q000201:enzymology / Q000378:metabolism*; D015689:Oncogene Protein p21(ras) / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000201:enzymology / Q000378:metabolism*; D012008:Recurrence
chemical_list: D014408:Biomarkers, Tumor; D015689:Oncogene Protein p21(ras)