The level and the activity of PAK1 are increased in myelodysplastic syndrome (MDS) (Pandolfi et al, 2015), and a gain in PAK1 gene copy number was found in cutaneous T cell lymphoma (mycosis fungoides/Sezary syndrome) (Mao et al, 2003). Here, PAK1 is linked to primary cutaneous T-cell non-Hodgkin lymphoma.