The FBP1-MV4-11 cell line was found to have significantly increased gene expression of fibroblast growth factor 21 (FGF21, 2.95-fold increase) and growth differentiation factor 15 (GDF15, 1.66-fold increase) (Figure 4B), which are biomarkers of mitochondrial dysfunction and OXPHOS deficiency [25,26]. The gene discussed is FGF21; the disease is hyperinsulinemic hypoglycemia, familial, 4.