Additionally, three proteins were under-expressed in samples of bladder cancer patients in this study: human leukocyte antigen class II histocompatibility antigen alpha chain (HLA-DMA), Na(+)/H(+) exchange regulatory cofactor 1 (NHE-RF1, SLC9A3R1) and uncharacterized protein C11orf52 (C11orf52). This evidence concerns the gene PROS1 and urinary bladder cancer.