PTK7 (Protein Tyrosine Kinase 7), also known as CCK4. is a transmembrane receptor belonging to the receptor tyrosine kinase (RTK) family, though it lacks intrinsic kinase activity due to a modified catalytic domain. Initially identified for its role in embryonic development and cell motility, PTK7 regulates planar cell polarity and non-canonical Wnt signaling pathways. It features an extracellular domain with seven immunoglobulin-like repeats, a transmembrane region, and a cytoplasmic pseudokinase domain. Dysregulation of PTK7 is implicated in cancer progression, including colorectal, lung, and acute myeloid leukemia, where it often exhibits overexpression linked to tumor invasion, metastasis, and poor prognosis.
PTK7 antibodies are essential tools for studying its biological functions and pathological roles. They enable detection of PTK7 expression in tissues or cells via techniques like immunohistochemistry, flow cytometry, and Western blot. Therapeutic PTK7-targeting antibodies are under exploration, particularly in antibody-drug conjugates (ADCs) and CAR-T cell therapies, leveraging its cancer-specific expression for precision targeting. Research also highlights PTK7's potential as a diagnostic or prognostic biomarker. However, its dual roles in tumor suppression and promotion, depending on context, necessitate further mechanistic studies. PTK7 antibodies thus serve as critical reagents in both basic research and translational oncology.