Mechanistically, 5-HTR2A and/or 5-HTR2C signaling promotes BC pathogenesis through two metabolic pathways: the JAK1/STAT3 pathway that promotes glycolysis through upregulation of pyruvate kinase M2 (PKM2) and the cAMP/PKA pathway that promotes the expression of peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC1α) leading to enhanced mitochondrial biogenesis 115. This evidence concerns the gene STAT3 and breast cancer.