Overexpression of the neu oncoprotein has been described in several tu
mor models including breast and prostate cancer. Overexpression of neu
has been reported to have prognostic significance in certain tumors b
ut controversy continues regarding the role and frequency of neu overe
xpression in prostatic cancer. The objectives of the study were twofol
d. First, to characterize nea expression in prostate cancer in compari
son to benign prostatic hyperplasia. Second, to determine whether nea
expression correlates with Gleason grade in prostate cancer. Thirty-ni
ne prostate cancers obtained from radical prostatectomy specimens and
10 benign prostatic hyperplasia specimens were included in the study.
Specimens were formalin fixed and paraffin-embedded. neu expression wa
s studied by immunohistochemical staining using a monoclonal nea speci
fic AB-3 antibody. All 39 specimens (100%) of prostate cancer showed p
ositive immunostaining of variable degree while 2 (20%) benign prostat
ic hyperplasia specimens showed positive staining. Thus, nea oncogene
is overexpressed in localized prostate cancer compared to benign prost
atic hyperplasia. The degree of neu immunostaining did not correlate w
ith Gleason grade and there appeared to be a tendency towards an inver
se relationship. The prognostic significance of the varying overexpres
sion is unknown.