Affiliations: University Department of Surgery, Division of Cancer
Sciences and Molecular Pathology, Glasgow Royal Infirmary, Glasgow, UK | Endocrine cancer group, Edinburgh Cancer Research
Centre, Western General Hospital, Crew Road South, Edinburgh, UK
Note: [] Corresponding author: Dr. Joanne Edwards, Section of Surgical
and Translational Research, Division of Cancer Sciences and Molecular
Pathology, University Department of Surgery, Level 2, Queen Elizabeth Building,
Glasgow Royal Infirmary, Glasgow, G31 2ER, UK. Tel.: +44 141 211 5441; Fax: +44
141 211 5432; E-mail: Je10b@clinmed.gla.ac.uk
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.
