Human Protein Tyrosine Phosphatase Receptor Type H (PTPRH) Protein

Background

PTPRH, also known as stomach cancer-associated protein tyrosine phosphatase-1 (SAP-1), is a receptor-like protein tyrosine phosphatase predominantly expressed in epithelial cells of the gastrointestinal tract. Structurally, PTPRH comprises an extracellular domain with multiple fibronectin type III repeats, a transmembrane region, and two intracellular phosphatase domains. PTPRH plays a role in epithelial cell signaling by regulating the activity of receptor tyrosine kinases, including EGFR (epidermal growth factor receptor). This regulation influences processes such as cell growth, differentiation, and migration. PTPRH is implicated in maintaining epithelial homeostasis and is overexpressed in gastrointestinal cancers, particularly gastric and colorectal cancers. Its dysregulation contributes to abnormal epithelial proliferation and cancer progression, making it a potential therapeutic target in oncology.