GDF15 and ovarian carcinoma: As shown in Fig. 1A–H, serum levels of B7-H3, IL-6, PLA2G7, GDF-15, SDC1, and VCAM-1 were significantly increased in ovarian cancer patients compared to healthy controls (B7-H3, IL-6, and GDF-15 at P < 0.0001; SDC1 at P < 0.01; PLA2G7 and VCAM-1 at P < 0.05), while ovarian cancer patients had significant lower serum IL-6 R alpha levels than healthy controls (P < 0.05).