This correlation was eloquently observed in human tumor samples beyond the convincing in vivo xenograft models, in which tumor cells expressing a non-degradable IP3R3 version or treated with geranylgeranyltransferase inhibitor (that prevents FBXL2 accumulation at ER membranes and activity, which depends on its geranylgeranylation 42) were greatly sensitized towards photodynamic therapy compared to tumor cells expressing wild-type (degradable) IP3R3 or untreated tumors. The gene discussed is ITPR3; the disease is neoplasm.