Fig. 3

MYC expression enhances de novo Fatty Acid synthesis. A-B) Carbon tracing experiments (U-13C) were conducted with labeling under normal culturing conditions. Cells were either treated with doxycycline or vehicle for 8 hours, followed by treatment with either dox, TOFA 3μg/ml or 10μg/ml for 24hrs. Palmitate tracing was conducted as previously described (62). A) Glucose tracing shows that de novo fatty acid synthesis is significantly lower in dox-treated cells, which is further repressed by TOFA treatment. Statistical analysis for m0 used ordinary onewayANOVA, and m+2 through m+16 utilized 2-way ANOVA. B) Total de novo palmitate synthesis levels from labeled Glucose. C-E) Untargeted Lipidomics: Similar experiments on 1712 MYC-dependent cells were subjected to an untargeted lipidomics profiling. C) Upon dox or TOFA (3μg/ml or 10μg/ml) for 24hrs, longer chain DGs are significantly lower compared to vehicle. D-E) Majority of the medium chain TGs and PCs also followed similar trends as observed in DGs which may have resulted from altered status of FASN, ACC and SCD. Statistical significance was determined by 2-way ANOVA