Inflammatory response in gastrointestinal cancers: Overview of six transmembrane epithelial antigens of the prostate in pathophysiology and clinical implications

Figure 2 Molecular structure diagram of six transmembrane epithelial antigens of the prostate 1-4. The six transmembrane epithelial antigens of the prostate (STEAP) family is composed of a group of cell surface transmembrane proteins with six potential transmembrane domains, one intracellular amino terminus, and a carboxyl terminus that exert physiological functions by acting as oxidoreductases. STEAP1-4 consist of 339, 490, 488, and 459 amino acid residues, respectively. Except STEAP1, the N-terminus of the STEAP2-4 proteins contains the F420H2:NADP+ oxidoreductase binding protein domain. TM: Transmembrane domain; STEAP: Six transmembrane epithelial antigen of the prostate.