Integrating lipidomic and transcriptomic analyses revealed that Niraparib disrupts sphingolipid metabolism and up-regulates the key kinase SPHK1; database mining further linked high SPHK1 to poor breast-cancer prognosis, and genetic or pharmacologic SPHK1 inhibition potentiated Niraparib-induced ferroptosis. The gene discussed is SPHK1; the disease is breast cancer.