In humans, the PTN gene is involved in carcinogenesis including mitogenesis, metastasis and angiogenesis, and it is expressed in a variety of cancers, such as lung [10], [62], colon [63], prostate [8], breast [7] and pancreas [64] as well as melanomas [9], neuroblastomas [65] and many carcinoma cell lines. Here, PTN is linked to melanoma.