Fig. 1: Elevated serum PGD2 and decreased expression of CRTH2 were correlated with DLBCL progression.

A The concentration of serum PGD2 was higher in DLBCL patients (n = 53) than healthy controls (n = 19). B We compared serum PGD2 concentration in DLBCL patients grouped according to IPI score, GCB subtype and B symptom, and found the association between serum PGD2 concentration and clinical features in DLBCL patients (n = 53). C Analysis of GSE56315 dataset showed the decreased mRNA expression level of CRTH2 in DLBCL patients. D To compare the expression of CRTH2 in DLBCL patients grouped according to stage, IPI score and therapeutic efficacy, analysis of GSE31312 dataset found the association between CRTH2 expression and clinical features in DLBCL patients. E, F Kaplan–Meier survival analysis showed the association between CRTH2 expression and OS and EFS in DLBCL patients, respectively. G RT-PCR results showed decreased expression of CRTH2 in DLBCL cell lines, including three GCB cell lines (LY1, LY8, VAL) and four non-GCB cell lines (LY3, LY10, U2932, and SU-DHL-2), in comparison with CD19⁺ B cells from PBMCs of three healthy donors (three time points). The expression of CRTH2 in healthy control (N1) was adjusted to 1. Data are shown as the mean ± SD. *p < 0.05; **p < 0.01; ***p < 0.001. Abbreviations: DLBCL diffuse large B-cell lymphoma, GCB germinal center B-cell-like, IPI international prognostic index, CR complete remission, PR partial remission, SD stable disease, PD progressive disease.