Tumor-Derived Extracellular Mutations of PTPRT/PTPρ Are Defective in Cell Adhesion

摘要: Receptor protein tyrosine phosphatase T (PTPRT/PTPrho) is frequently mutated in human cancers including colon, lung, gastric, and skin cancers. More than half of the identified tumor-derived mutations are located extracellular part PTPrho. However, functional significance those domain remains to be defined. Here we report that PTPrho mediates homophilic cell-cell aggregation. This interaction very specific because does not interact with its closest homologue, PTPmu, a cell aggregation assay. We further showed all five NH(2)-terminal MAM immunoglobulin domains impair, varying extents, their ability form aggregates, indicating loss-of-function mutations. Our results suggest may play an important role adhesion mutational inactivation this could promote tumor migration metastasis.