Tyrosine-protein kinase FRK (FRK)

Tyrosine-protein kinase FRK, also known as Fyn-related kinase or protein tyrosine kinase 5, is a member of the TYR family of protein kinases encoded by the *FRK* gene in humans. It is a nuclear-localized enzyme that may function during G1 and S phases of the cell cycle to suppress cellular growth. This protein has been shown to interact with retinoblastoma protein and is predominantly expressed in epithelial tissues. As a non-receptor tyrosine kinase, it plays roles in signal transduction pathways regulating cell proliferation and has been studied as a potential tumor suppressor[3][5][6]. Several approved drugs act on this target by inhibiting its enzymatic activity, making it relevant for cancer therapy research[3].

Other names

Fyn-related kinaseNuclear tyrosine protein kinase RAKProtein-tyrosine kinase 5PTK5RAKGTKfyn-related Src family tyrosine kinase

Drugs targeting this molecule generally act as **kinase inhibitors**, blocking the phosphorylation activity of the enzyme, thereby interfering with downstream signaling pathways involved in cell growth and survival[1][2].