Fig. 3
Kaplan–Meier survival curves based on 274 patients with HNSCC according to the methylation status of the nine prostanoid receptor genes. DFS with respect to aPTGDR1, bPTGDR2, cPTGER1, dPTGER2, ePTGER3, fPTGER4, gPTGFR, hPTGIR, and iTBXA2R in the case of methylated (red lines) and unmethylated (blue lines) genes. j Combined analysis of the nine genes. Blue line: patients with 0–4 methylated genes; red line: patients with 5–9 methylated genes. *P < 0.05