Dysregulated cholesterol homeostasis results in resistance to ferroptosis increasing tumorigenicity and metastasis in cancer

High cholesterol has been associated with increased risk of cancer but the underlying mechanism is not completely understood. Here, the authors show that a cholesterol metabolite induces metabolic reprogramming that generates ferroptosis-resistant cancer cells leading to increased tumour growth and metastasis. Hypercholesterolemia and dyslipidemia are associated with an increased risk for many cancer types and with poor outcomes in patients with established disease. Whereas the mechanisms by which this occurs are multifactorial we determine that chronic exposure of cells to 27-hydroxycholesterol (27HC), an abundant circulating cholesterol metabolite, selects for cells that exhibit increased cellular uptake and/or lipid biosynthesis. These cells exhibit substantially increased tumorigenic and metastatic capacity. Notably, the metabolic stress imposed upon cells by the accumulated lipids requires sustained expression of GPX4, a negative regulator of ferroptotic cell death. We show that resistance to ferroptosis is a feature of metastatic cells and further demonstrate that GPX4 knockdown attenuates the enhanced tumorigenic and metastatic activity of 27HC resistant cells. These findings highlight the general importance of ferroptosis in tumor growth and metastasis and suggest that dyslipidemia/hypercholesterolemia impacts cancer pathogenesis by selecting for cells that are resistant to ferroptotic cell death.

Automated summary

High cholesterol levels have been associated with increased risk of cancer, with cholesterol metabolite 27HC potentially leading to the generation of cancer cells resistant to ferroptosis, thereby promoting tumor growth and metastasis. These findings emphasize the significance of ferroptosis in tumor development and suggest that dyslipidemia/hypercholesterolemia impacts cancer pathogenesis by selecting for cells resistant to ferroptotic cell death.