Lipid Storage and Autophagy in Melanoma Cancer Cells
AbstractCancer stem cells (CSC) represent a key cellular subpopulation controlling biological features such as cancer progression in all cancer types. By using melanospheres established from human melanoma patients, we compared less differentiated melanosphere-derived CSC to differentiating melanosphere-derived cells. Increased lipid uptake was found in melanosphere-derived CSC vs. differentiating melanosphere-derived cells, paralleled by strong expression of lipogenic factors Sterol Regulatory Element-Binding Protein-1 (SREBP-1) and Peroxisome Proliferator-Activated Receptor-γ (PPAR-γ). An inverse relation between lipid-storing phenotype and autophagy was also found, since microtubule-associated protein 1A/1B-Light Chain 3 (LC3) lipidation is reduced in melanosphere-derived CSC. To investigate upstream autophagy regulators, Phospho-AMP activated Protein Kinase (P-AMPK) and Phospho-mammalian Target of Rapamycin (P-mTOR) were analyzed; lower P-AMPK and higher P-mTOR expression in melanosphere-derived CSC were found, thus explaining, at least in part, their lower autophagic activity. In addition, co-localization of LC3-stained autophagosome spots and perilipin-stained lipid droplets was demonstrated mainly in differentiating melanosphere-derived cells, further supporting the role of autophagy in lipid droplets clearance. The present manuscript demonstrates an inverse relationship between lipid-storing phenotype and melanoma stem cells differentiation, providing novel indications involving autophagy in melanoma stem cells biology. View Full-Text
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Giampietri, C.; Petrungaro, S.; Cordella, M.; Tabolacci, C.; Tomaipitinca, L.; Facchiano, A.; Eramo, A.; Filippini, A.; Facchiano, F.; Ziparo, E. Lipid Storage and Autophagy in Melanoma Cancer Cells. Int. J. Mol. Sci. 2017, 18, 1271.
Giampietri C, Petrungaro S, Cordella M, Tabolacci C, Tomaipitinca L, Facchiano A, Eramo A, Filippini A, Facchiano F, Ziparo E. Lipid Storage and Autophagy in Melanoma Cancer Cells. International Journal of Molecular Sciences. 2017; 18(6):1271.Chicago/Turabian Style
Giampietri, Claudia; Petrungaro, Simonetta; Cordella, Martina; Tabolacci, Claudio; Tomaipitinca, Luana; Facchiano, Antonio; Eramo, Adriana; Filippini, Antonio; Facchiano, Francesco; Ziparo, Elio. 2017. "Lipid Storage and Autophagy in Melanoma Cancer Cells." Int. J. Mol. Sci. 18, no. 6: 1271.
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