(1) Multipathway regulation: For example, SCFAs concurrently activate both MAPK and PI3K pathways in prostate cancer models; DCA bidirectionally modulates MAPK/PI3K/Wnt signaling in CRC; KYNA suppresses MAPK/PI3K activity while exerting complex regulation on β-catenin expression in HT-29 cells. The gene discussed is PIK3CA; the disease is Familial prostate cancer.