STIM2 and Familial prostate cancer: Other isoforms of STIM and ORAI, such as STIM2, ORAI2 and ORAI3 and some transient receptor potential (TRP) family members that involved in the regulation of SOCE activity might also be differently expressed in prostate cancer cells, which may account for the phenomenon observed in Fig. 2A that although DU145 and PC3 showed more STIM1 expression and almost similar or slight increase of ORAI1 when compared with those of LNCaP, their SOCE activity obviously decreased.