The Expression of Vitamin D Associated Markers in High Grade Prostatic Intraepithelial Neoplasia (HGPIN)
S Sasturkar, A Blutreich, TW He, M Nagar, J Small, L Chiriboga, R Hayes, J Melamed, J Ahn. NYU School of Medicine, New York, NY
Background: There has been increasing evidence that vitamin D may participate in early prostate cancer carcinogenesis. We have examined tissue protein expression of vitamin D activating (CYP27A1) and deactivating (CYP24) enzymes of 1,25-dihydroxy vitamin D, an active vitamin D metabolite and the vitamin D receptor (VDR) in high grade prostate intraepithelial neoplasia (HGPIN) compared to adjacent normal prostate tissue.
Design: HGPIN tissue microarrays were constructed from radical prostatectomy specimens (n=46 cases) to include foci of HGPIN (4 cores/case) and of non-neoplastic peripheral zone. Immunohistochemical studies using commercially available antibodies against CYP24 (Goat Polyclonal C-18; Santa Cruz), CYP-27A1(Goat Polyclonal P-17; Santa Cruz) and VDR (Rabbit Polyclonal C-20; Santa Cruz) were performed on an automated immunostainer (Benchmark; Ventana Medical Systems, Tucson, AZ). Tissue microarray stained slides were scored manually using an intensity + proportion score (range: 0-8). The mean expression level difference between HGPIN and non-neoplastic prostate tissue was tested by t-test.
Results: The cohort studied included 46 male, mean age 61 (range 46-74), mean Gleason score 6.6 (range 6-7), tumor stage pT2-pT3. The expression of these markers was as follows:
|Marker||HGPIN||Non neoplastic Prostate tissue||significance by t-test|
|CYP-27A1||5.7||6.1||P < 0.05|
|VDR||6.1||6.4||P < 0.05|