STK26 (serine/threonine kinase 26) is a serine/threonine protein kinase that functions as a key regulator of cell migration, autophagy, and tumor progression. The protein acts as a mediator of cell growth and modulates apoptosis through its kinase activity 1. STK26 negatively regulates Golgi reorientation during polarized cell migration upon RHO activation, working in association with STK24 2. A critical mechanism involves STK26's phosphorylation of ATG4B at Ser-383, which increases autophagic flux and promotes tumor cell survival 1. The kinase is part of STRIPAK (striatin-interacting phosphatase and kinase) complexes that regulate multiple signaling pathways including Hippo, MAPK, and cytoskeleton remodeling 1. In cancer contexts, STK26 demonstrates oncogenic properties by promoting colorectal cancer cell growth, proliferation, and migration through stabilization of ATF6 protein 3. The protein also shows prognostic significance in melanoma, where its expression correlates with patient outcomes 4. Additionally, STK26 expression is upregulated in pediatric acute myeloid leukemia stem cells and correlates with improved relapse-free survival 5. Structural variations in STK26 have been identified as potential predisposition factors for severe COVID-19 6.