Among such efforts, induction of ER stress by targeting SERCA might be a potential therapeutic strategy to treat apoptosis-resistant cancer cells.27, 28 Our previous study identified that SBF-1, a synthetic steroidal glycoside, had a very strong antitumor activity in various cancer types.29, 30 Herein, we report a new property of SBF-1 for characterizing its anticancer activity as a SERCA inhibitor that directly binds to SERCA2. The gene discussed is ATP2A2; the disease is cancer.