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bioRxiv · 10.1101/479964

A serum-free and insulin-supplemented cell culture medium ensures fatty acid synthesis gene activation in cancer cells

Wu, S.·Naar, A. M.
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Abstract

While investigating the role played by de novo fatty acid biosynthesis (DNFA) in cancer cells, we sought a medium condition that would support cell proliferation without providing any serum lipids. Here we report that a defined serum free cell culture medium condition containing insulin, transferrin and selenium (ITS) supports controlled study of DNFA regulation in melanoma cell lines. This lipid-free ITS medium is able to support proliferation of melanoma cell lines that fulfill their lipid requirements via DNFA. We show that the ITS medium stimulates gene transcription in support of both DNFA and de novo cholesterol synthesis (DNCS), specifically mediated by SREBP1/2 in melanoma cells. We further found that the ITS medium promoted SREBP1 nuclear localization and occupancy on DNFA gene promoters. Our data show clear utility of this serum and lipid-free medium for melanoma cancer cell culture and lipid-related areas of investigation.

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Wu, S., Naar, A. M.. 2018-11-29. A serum-free and insulin-supplemented cell culture medium ensures fatty acid synthesis gene activation in cancer cells. https://doi.org/10.1101/479964

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