The higher tumor growth inhibition effect of Conj2 over Conj1 where the Dau is connected to the N-terminus, confirms our previous results with Dau-GnRH-III (Glp-His-Trp-Lys(Bu)-His-Asp-Trp-Lys(Dau=Aoa)-Pro-Gly-NH2), suggesting that H-Lys(Dau=Aoa)-OH can release easily from this position by the dipeptidyl-peptidase activity of cathepsin B. Here, CTSB is linked to neoplasm.