MED15–HIF–CPT1A axis maintains lipid homeostasis and promotes tumor progression. The proposed model suggests that MED15 promotes cancer progression during hypoxia. In hypoxia, stabilized HIFα forms a dimeric complex with HIFβ and binds to the HRE of MED15. MED15 acts as a transcriptional coactivator of HIF, facilitating its binding to the promoter of CPT1A. Due to its role as a HIF-repressed gene, CPT1A protein levels decrease, leading to increased storage of fatty acids in the cytoplasm as LD, thereby promoting tumor progression. CPT1A, carnitine O-palmitoyltransferase 1; HIF, hypoxia-inducible factor; MED15, Mediator complex subunit 15.
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