Fig. 4
Enrichment in lipid and amino acid metabolism enzymes in TumHIGH GBM cells and tissues. a Gene ontology analysis of the 66 metabolism genes identified among genes overexpressed in both GBM TumHIGH cells and tissues. DAVID toolkit. b Schematic representation of the lipid and amino acid metabolic pathways containing genes overexpressed in TumHIGH GBM cells and tissues. Asterisks mark genes coding for components of the glycine, serine and threonine metabolism. LA: linoleic acid; ALA: linolenic acid; ETA: eicosatetraenoic acid; EPA; eicosapentaenoic acid; ADA: docosatetraenoic acid; CA: clupanodonic acid; TTA: tetracosatetraenoic acid; TPA: tetracosapentaenoic acid; THA: tetracosahexaenoic acid. c Modeling interconnections between the 66 metabolism genes highlights ELOVL2 at the most densely connected node of the network. Gene network built on the basis of the gene expression values across all GBM cells using MIIC tool. Line thickness represents the strength of the edge. Arrowheads linking variables in a v-structure of the type x → y ← z denotes the absence of a graphical structure of the type: x → y → z, x ← y ← z and x ← y → z (variable x cannot be reached passing through y, nor y passing through x, nor y is a common parent of the two other variables). These 3 models can be excluded since in a v-structure y does not mediate mutual information between x and z