To unveil the underlying signaling pathway, SphK1 knockout PCa cells were treated with exogenous S1P before the addition of specific inhibitors for MAPK (e.g., PD98059 or GSK1120212) or PI3K‐Akt (e.g., LY294002 or BEZ235) or JAK inhibitor (e.g., Ruxolitinib) and the results (Figure 4A and B and Supporting information S4A‐C) indicated the exclusive role of MAPK pathway in S1P‐induced NED of PCa cells. The gene discussed is SPHK1; the disease is posterior cortical atrophy.