The FAT1 gene deficiency in breast cancer affects resistance to CDk4/6 inhibitor therapy22; FAT1 mutations are associated with poor survival in head and neck squamous cell carcinoma (HNSCC)23,24; Some studies suggest that FAT1 may be an immune response regulator involved in different inflammatory processes, as has been argued in gliomas and T-cell lymphomas25,26. The gene discussed is CDK4; the disease is head and neck squamous cell carcinoma.