The alteration of the sarco/endoplasmic reticulum Ca2+ ATPase 3 (SERCA3) – a SERCA-type Ca2+ pump – during tumorigenesis was confirmed in several different cancer types such as breast, lung, brain, colon, gastric carcinomas or leukemias, using either cancer cell lines or tissues [11–16]. The gene discussed is ATP2A3; the disease is cancer.