The activity of the following pathways varied depending on the status of hematogenous metastasis (p-value < 0.03): pathways associated with focal adhesion; PI3K-Akt-mTOR signaling, MAPK signaling, prostaglandin synthesis and regulation, PI3K-Akt signaling, circadian rhythm genes, adipogenesis, integrated breast cancer, eicosanoid synthesis, calcium regulation in cardiac cells, and an overview of proinflammatory and profibrotic mediators. It is important to note that 30% of these signaling pathways (highlighted in bold) were 100% represented by downregulated genes. The gene discussed is PIK3CA; the disease is breast cancer.