Oncogenes, including Myeloid cell leukemia-1 (Mcl-1), B-cell lymphoma-2 (Bcl-2), serve to inhibit mitochondrial Ca2+ overload and enhance the viability of cancer cells, whereas tumor suppressor genes such as PTEN and Breast cancer susceptibility gene (BRCA2) facilitate ER-mitochondria Ca2+ transfer and trigger apoptosis in cancer cells [168, 176]. This evidence concerns the gene BCL2 and cancer.