Cholesterol homeostasis modulates platinum sensitivity in human ovarian cancer

Here we show that platinum-resistant ovarian cancer cells also show reduced cholesterol biosynthesis, and mostly rely on uptake of exogenous cholesterol for their needs. Expression of FDPS and OSC, enzymes involved in cholesterol synthesis, are decreased both in drug-resistant cells and upon TRAP1 silencing, whereas the expression of LDL receptor, the main mediator of extracellular cholesterol uptake, is increased. Strikingly, treatment with different statins to inhibit cholesterol synthesis reduces cisplatin-induced apoptosis, whereas silencing of LIPG, an enzyme involved in lipid metabolism, increases sensitivity to the drug. Evaluation of differentially expressed transcripts in PEA1 ovarian cancer cells following transfection with TRAP1-directed siRNA or control siRNA