Endogenous Sterol Metabolites Regulate Growth of EGFR/KRAS-Dependent Tumors via LXR

Autor: Gabitova, Linara, Restifo, Diana, Gorin, Andrey, Manocha, Kunal, Handorf, Elizabeth, Yang, Dong-Hua, Cai, Kathy Q., Klein-Szanto, Andres J., Cunningham, David, Kratz, Lisa E., Herman, Gail E., Golemis, Erica A., Astsaturov, Igor
Zdroj: Cell Reports; September 2015, Vol. 12 Issue: 11 p1927-1938, 12p
Abstrakt: Meiosis-activating sterols (MAS) are substrates of SC4MOL and NSDHL in the cholesterol pathway and are important for normal organismal development. Oncogenic transformation by epidermal growth factor receptor (EGFR) or RAS increases the demand for cholesterol, suggesting a possibility for metabolic interference. To test this idea in vivo, we ablated Nsdhlin adult keratinocytes expressing KRASG12D. Strikingly, Nsdhlinactivation antagonized the growth of skin tumors while having little effect on normal skin. Loss of Nsdhlinduced the expression of ATP-binding cassette (ABC) transporters ABCA1 and ABCG1, reduced the expression of low-density lipoprotein receptor (LDLR), decreased intracellular cholesterol, and was dependent on the liver X receptor (LXR) α. Importantly, EGFR signaling opposed LXRα effects on cholesterol homeostasis, whereas an EGFR inhibitor synergized with LXRα agonists in killing cancer cells. Inhibition of SC4MOL or NSDHL, or activation of LXRα by sterol metabolites, can be an effective strategy against carcinomas with activated EGFR-KRAS signaling.
Databáze: Supplemental Index