ADAMTS1, a putative anti-angiogenic factor, is decreased in human prostate cancer

Abstract

Objective To investigate the expression of 'ADAM metallopeptidase with thrombospondin type I motif, 1' (ADAMTS1) in human prostate cancer, and to study its relationship to microvessel density (MVD) and metastasis. ADAMTS1 has been described as an anti-angiogenic and antitumour factor, but its function in prostate cancer is unknown. Patients and methods ADAMTS1 expression was evaluated by immunohistochemistry in specimens obtained by transurethral resection of the prostate from patients with hormone-naïve and hormone-refractory prostate tumours, including adjacent benign tissue. A semiquantitative scoring system was used for evaluating the staining. MVD was quantified by counting the number of CD34-positive blood vessels. Results ADAMTS1 was strongly expressed in the luminal epithelial cells in benign prostate glands, whereas expression was significantly lower in prostate cancer cells. There was no obvious difference between hormone-naïve and hormone-refractory tumours, and ADAMTS1 expression did not correlate with Gleason score. However, in hormone-refractory tumours from patients with metastatic disease, the expression of ADAMTS1 was significantly lower than in tumours from patients without metastases. Furthermore, the MVD was higher in hormone-refractory than in hormone-naïve tumours and benign tissue, and MVD correlated with Gleason score. There was no association between ADAMTS1 and MVD in the hormone-naïve tumours, while hormone-refractory tumours with low ADAMTS1 expression had a higher MVD than those with moderate/high expression. CONCLUSION ADAMTS1 expression is decreased in prostate cancer, and might be involved in the early steps of prostate cancer development. Further, ADAMTS1 might have an anti-angiogenic and antimetastatic role in hormone-refractory prostate cancer, where low ADAMTS1 expression is associated with a high MVD and metastasis. © 2009 BJU INTERNATIONAL.