Low nuclear ErbB3 predicts biochemical recurrence in patients with prostate cancer.
OBJECTIVE
To further evaluate the association between the cytoplasmic or nuclear localization of ErbB3 with biochemical recurrence (BCR) in patients with prostate cancer and positive surgical margins, as there is a greater risk of BCR for such patients after radical prostatectomy (RP).


METHODS
We recently noted that ErbB3, which is normally associated with the plasma membrane, can translocate to the nucleus, an event which appears to be associated with disease progression. We evaluated ErbB3 expression and localization using immunohistochemistry on tissue samples from 55 patients with positive surgical margins after RP; 30 of these 55 (55%) had BCR after 3 years of follow-up. The relationship between ErbB3 nuclear localization and BCR (prostate-specific antigen, PSA, >0.3 ng/mL) after RP was analysed by Kaplan-Meier survival analysis and Cox regression models.


RESULTS
The BCR-free survival probability at 3 years was 0.65 and 0.35 for positive and negative nuclear ErbB3, respectively (Kaplan-Meier, P = 0.029). Patients negative for nuclear ErbB3 had a 2.47-fold increase in BCR frequency in a univariate Cox model (P = 0.008) and it remained an independent prognostic marker when combined with clinical prognostic variables in a multivariate model (P = 0.023).


CONCLUSIONS
Low nuclear localization of ErbB3 is a predictor of BCR in patients with prostate cancer and positive surgical margins after RP.
Koumakpayi
Ismaël H
IH
Centre de recherche du Centre Hospitalier de l'Université de Montréal and Institut du cancer de Montréal, Montreal, Quebec, Canada.
Diallo
Jean-Simon
JS
Le Page
Cécile
C
Lessard
Laurent
L
Filali-Mouhim
Abdelali
A
Bégin
Louis R
LR
Mes-Masson
Anne-Marie
AM
Saad
Fred
F
D000368:Aged; D015153:Blotting, Western; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000378:metabolism* / Q000401:mortality; D020893:Receptor, ErbB-3 / Q000378:metabolism*; D012044:Regression Analysis; D016019:Survival Analysis
D020893:Receptor, ErbB-3; D017430:Prostate-Specific Antigen