Family with sequence similarity 171 member A1 (FAM171A1)

Family with sequence similarity 171 member A1 (FAM171A1), also known as Astroprincin (APCN), is a conserved type I transmembrane glycoprotein approximately 98 kDa in size, with two-thirds of its structure residing within the cytoplasm and a smaller, glycosylated extracellular domain[2][4][6]. FAM171A1 is physiologically expressed in brain astrocytes and various tissues such as placenta, muscle, kidney, and pancreas[2][4]. Functionally, it regulates cytoskeletal dynamics by influencing cell shape and actin stress fiber assembly[1][6]. In cancer biology, FAM171A1 is overexpressed in invasive and aggressive tumors including triple-negative breast cancers, melanomas, and oral tongue squamous cell carcinomas, where it correlates with increased invasiveness, epithelial-mesenchymal transition (EMT) marker expression, and poor prognosis[4][6]. Its expression is negatively regulated by estrogen receptor alpha via miR-590-5p, with higher FAM171A1 levels observed in estrogen receptor-negative cancers[6]. There are currently no approved drugs or known small molecules directly targeting FAM171A1, but it is considered a potential therapeutic and prognostic target in oncology[6][4].

Other names

AstroprincinAPCNC10orf38FLJ12884Protein FAM171A1astroprincin