ATP2A3 and Familial prostate cancer: Although TG, a sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) inhibitor, induced endoplasmic reticulum (ER) Ca2+ store release was lower (Fig. S1A), SOCE activity was significantly greater in the prostate cancer cell lines than in the BPH-1 cells (Fig. 2B,C), which is consistent with the expression of STIM1 in these cell lines.