PTPRK (protein tyrosine phosphatase receptor type K) is a membrane-bound receptor tyrosine phosphatase that functions as a tumor suppressor and regulator of cellular adhesion and metabolism 1. The protein contains an extracellular domain for cell-cell adhesion, a transmembrane region, and two intracellular catalytic domains, and undergoes proteolytic processing by Furin, ADAM10, and γ-secretase to generate functional subunits including an intracellular fragment that regulates β-catenin signaling 1. PTPRK negatively regulates EGFR signaling in keratinocytes and intestinal cells, with its expression cooperatively controlled by Notch and TGF-β pathways 23. In metabolic contexts, PTPRK promotes hepatocyte reprogramming by regulating glycolysis and lipogenesis, targeting fructose-1,6-bisphosphatase 1 to enhance PPARγ-mediated lipogenic signaling 4. Clinically, PTPRK demonstrates tumor suppressor activity in colorectal cancer through both catalytic-dependent and independent mechanisms, promoting intestinal repair and suppressing epithelial-mesenchymal transition 5. Loss of PTPRK expression is associated with celiac disease pathology and contributes to increased intestinal proliferation 3. Additionally, PTPRK variants are associated with Alzheimer's disease risk in Hispanic populations, suggesting roles in neuronal development 6.