PTGDR2 and diffuse large B-cell lymphoma: Kaplan–Meier survival curve analysis showed that DLBCL patients with high CRTH2 expression displayed worse overall survival (OS) (p < 0.001, Fig. 1E) and event-free survival (EFS) (p < 0.001, Fig. 1F), suggesting the involvement of CRTH2 in DLBCL progression.