Upon 5‐aza treatment, a down‐regulated expression of two tumour suppressors, THBS4 and PTPRG were restored,9 as well as a potential epigenetic diagnostic marker CMTM28 and miR200c involved in activation of Notch pathways in CTCL.17 Here, PTPRG is linked to primary cutaneous T-cell non-Hodgkin lymphoma.