Figure 6 from PPARδ Orchestrates a Prometastatic Metabolic Response to Microenvironmental Cues in Pancreatic Cancer

PPARδ rewires cellular metabolism regulating MYC/PGC1A balance. A, Expression of MYC, PGC1A, and MYC/PGC1A ratio in PDX-354 after mitochondrial energy deprivation during 48 to 72 hours (n = 4–7). B,MYC and PGC1A reporter assay. Promoter activity was estimated as luciferase bioluminescence at the indicated times following treatment with PPARδ agonist GW0742 or PPARD overexpression (PPARD OE; n = 3–5). C, PDAC-354 cells were transduced with inducible lentiviral vectors expressing either a nontargeting short hairpin RNA (NT shRNA) or two different shRNAs against MYC (sh#1 and sh#2) or the complete cDNA of PGC1A. Effect of MYC knockdown (shMYC, pooled data for sh#1 and sh#2) or PGC1A overexpression (PGC1A OE) on invasiveness in response to treatment with 5 μmol/L PPARδ agonist L-165 for 48 hours (n = 6–8). D, CUT&Tag analysis of MYC protein binding at the CCNE, PGC1A, SNAI2, and VIM loci. WashU Epigenome Browser tracks showing CUT&TAG signals at the mentioned loci with the indicated transcription start site (TSS). Blue signals represent MYC binding in control (Ctrl) conditions, and red signals represent MYC binding upon 24 hours of etomoxir (Eto) treatment in PDAC-002 cells. E–H, PDAC-215 and 354 cells were transduced as in A, pretreated with doxycycline for 48 hours, and then incubated with MCM or etomoxir. E, OCR changes for maximal respiration (Max resp; left) and ATP-linked respiration (n = 4; right). F, Glycolytic (Glyco) capacity (left) and reserve (n = 4; right). G,ZEB1 gene expression. H, Invasive capacity (n = 10). I, PDAC-354 cells were treated with MCM or 20 μmol/L etomoxir for 48 hours in the presence or absence of the MYC/Max interaction inhibitor Mycro3 (25 μmol/L). Cells were then seeded in modified Boyden invasion chambers containing 20% FBS in the lower compartment. The number of invasive cells was assessed after 16 hours (n = 5). In E, F, and H, the bars represent pooled data from PDAC-215 and 354, showing individual data points corresponding to each PDX. All data are represented as the mean ± SEM. #, P < 0.05; ##, P < 0.01; ###, P < 0.001 vs. unstimulated control. *, P < 0.05; **, P < 0.01; ***, P < 0.001 vs. NT. See also Supplemenatry Figs. S10–S13.