To determine the effect of combined inhibition of Src and IGF-1R in a direct xenograft of human PCa cells growing in mouse models, we first treated mice bearing the primary human xenograft MDA PCa 133 tumors (castrate-resistant, AR positive) with dasatinib and BMS-754807 alone and in combination(n = 4 for each group). This evidence concerns the gene SRC and posterior cortical atrophy.