Pigment epithelium-derived factor as a new diagnostic marker for melanocytic tumors.

Pigment epithelium-derived factor (PEDF), a potent antiangiogenetic factor, has been lately known to correlate well with angiogenic and metastatic potentials of tumor cells. We investigated the expression of PEDF protein in various types of human tumor cells by an immunohistochemical technique using a monoclonal antibody. Consequently, we found the significantly frequent and intense expression of PEDF in human melanocytic tumor cells including malignant melanoma as compared to non-melanocytic ones.