Overexpression of CD73 in prostate cancer is associated with lymph node metastasis

Prostate cancer is the most common malignancy in men in Europe and North America. At present, it is becoming an increasingly common cancer in China. CD73 (ecto-5'-nucleotidase) is a glycosylphosphatidylinositol (GPI)-linked 70-kDa cell surface enzyme. It is also broadly expressed in many types of tissues. Recent studies have showed that CD73 is widely expressed on malignancies and is up-regulated in cancerous tissues. Consequently, we analyzed the expression of CD73 in prostate cancer tissue. The expression of the CD73 protein was evaluated by Immunohistochemistry staining in 116 tissue specimens. The expression was further examined by quantitative real-time PCR (qRT-PCR) and Western blot in the same set of patients. The intense cell membrane staining for the CD73 protein was observed. The expression of CD73 in lymph node non-metastasizing prostate cancer tissues can be seen at low levels, and is generally undetectable. RT-PCR and Western blot showed that the expression of CD73 in lymph node metastasizing prostate cancer was higher compared with non-metastasizing ones. These results suggest that CD73 could be considered as a relevant-specific target for molecular therapy of prostate cancer metastasis.