Immunohistochemical results from our cohort showed that C3AR1 expression was higher in the ovarian cancer group than in the normal group (Figure S1A).In the TCGA OC HumanMethylation450K cohort, transcription levels of C3AR1 in OC patients were negatively correlated with its DNA methylation levels (cg09238677, r=-0.186, p < 0.05; cg23205183, r=-0.112, p < 0.05). This evidence concerns the gene C3AR1 and ovarian cancer.