Activated Cdc42‐associated kinase 1 (ACK1), a widely expressed nonreceptor tyrosine kinase, is often amplified in cancer and has been shown to interact with Cell division cycle 42 (Cdc42), Epidermal growth factor receptor (EGFR), and several other cancer‐relevant molecules, suggesting a possible role for ACK1 in development and tumor formation. This evidence concerns the gene CDC42 and neoplasm.