Most importantly, mortalin protein analysis of a matched cell line series derived from ascites or pleural effusions from two patients with HGSOC before and after development of clinical platinum resistance (PEO1 sensitive/PEO4 resistance and PEO14 sensitive/PEO23 resistance) identified significantly higher mortalin expression in platinum-resistant cells compared to platinum-sensitive cells (p < 0.003 and p < 0.04, respectively, Figure S1c), indicating mortalin as an one of the factors that can promote drug resistance in OC. The gene discussed is HSPA9; the disease is Pleural effusion.