As a first step to investigate associations of IGF axis components with immune factors, we analyzed effects of IGF-1 on gene expression in three PCa cell lines: two human, androgen receptor (AR)-positive 22Rv1 cultured from a xenograft established from primary PCa, and AR-negative DU145 derived from metastatic cancer; and one murine, Myc-CaP, derived from primary adenocarcinoma in the Hi-Myc mouse22. The gene discussed is IGF1; the disease is metastatic malignant neoplasm.