GTSF1 and primary cutaneous T-cell non-Hodgkin lymphoma: Malignant T cells in the TCyEM group showed upregulated expression of a series of cytotoxic molecules and chemokines, including GZMA, GZMH, NKG7 and CCL4, while the gene signature of the TCM group included several genes previously reported in studies of advanced-stage CTCL, including TOX, KIR3DL2, CD40LG, GTSF1, PTTG1, GAPDH, PPIA and HSPD127–32.