PTPRD and cancer: PTPRD is capable of directly interacting with PTPRS [22], the cytoskeletal remodeling proteins liprin-α-1 and MIM (Missing in Metastasis) [23,24], and STAT3 [26,30,33], which suggests that PTPRD may play a functional role in cancer cell survival, adhesion, and/or migration through the signaling mechanisms mediated by these substrates.