In our study, the high expression of PTGDS protein was correlated with worse prognosis in PTCL patients, and targeting PTGDS by gene knockdown and AT56 treatment could suppress tumor growth in vitro and in vivo through regulating cell proliferation, cell cycle, cell apoptosis and invasion. The gene discussed is PTGDS; the disease is mature T-cell and NK-cell non-Hodgkin lymphoma.