Differential Expression of Apolipoprotein-D and Prostate Specific Antigen in Benign and Malignant Prostate Tissues

Abstract
To investigate Apolipoprotein-D (Apo-D) and prostate specific antigen (PSA) immunohistochemical staining of nonmalignant and malignant human prostate tissues. Apolipoprotein-D and PSA immunoreactivity were evaluated by video image analysis in nonmalignant prostates and in 30 stage D sub 2 prostate cancers. Apolipoprotein-D was detected in all 30 tumors, and the level of staining was elevated in comparison to age-matched nonmalignant prostates (p less than 0.05). In contrast, the level of PSA staining in tumors was less than that detected in nonmalignant prostates. Apolipoprotein-D is expressed in normal human prostate. Elevated Apo-D staining is associated with advanced prostate cancer.