AP1S2 and urinary bladder cancer: Wang et al. discovered adaptor-related protein complex 2 subunit sigma 1 (AP2S1), prolyl-3 hydroxylase family member 4 (P3H4), and rac family small GPTase 3 (RAC3) as potential tumor-specific antigens (TSAs) for bladder cancer on the basis of their expression levels and associations with prognoses when analyzing 165 primary bladder cancer tissue samples across four stages I-IV (103 superficial and 62 invasive) [35].