According to the Human Protein Atlas database, six proteins (ATE1, AZGP1, ITIH4, PTGDS, VMO1, MASP2) are expressed in normal as well as tumor prostate tissue by immunohistochemical staining with two additional proteins (AMBP, CD59), localized only in normal prostate tissue and five (TF, HP, HBB, APCS, RBP4) found only in tumor tissue. Here, RBP4 is linked to neoplasm.