Taking into consideration the preclinical studies that have demonstrated an increased tumoral uptake of 64CuCl2 in PCa cell lines and tumor xenografts expressing hCTR1 [18,26], we next investigated whether the increased 64CuCl2 uptake observed in the tumoral cell lines (Figure 1A) could be correlated with higher levels of copper transporters, using western blot followed by densitometry analysis. This evidence concerns the gene SLC31A1 and neoplasm.