PTGDS and mature T-cell and NK-cell non-Hodgkin lymphoma: As PTGDS was a kind of secreted protein, we further evaluated the level of serum PTGDS and found that compared with healthy control (n = 31), PTCL patients (n = 76) displayed lower level of serum PTGDS (p < 0.01) (Supplementary Fig. S1D), indicating the reduced secretion of PTGDS protein in PTCL cells.