FOLH1 and Familial prostate cancer: We observe decreasing uptake of [99mTcO2(DPX-PSMAt)2]+ (X = Ph, An, MEP) radiotracer analogues in PSMA-positive prostate cancer cells in the order Ph > An > MEP and we note that this corresponds with increasing size and hydrophilicity of the para substituents: H < OCH3 < OCH2CH2OCH3.