Figure 1. Mitochondrial fission and maintenance of the cancer stem cell pool in prostate tumors. (A) Mitochondrial dynamics comprises cycles of organelle fusion and fission ensuring the fitness of the mitochondrial population in a cell. (B) Mitochondrial fission allows removal of dysfunctional organelles by mitophagy and segregation of aged, non-functional mitochondria to non-stem cells during cell division. (C) Blocking mitochondrial fission, as in the case of BRD4 knockdown or treatment with BET inhibitors, impairs correct segregation and clearance of dysfunctional mitochondria during asymmetric cell division with consequent senescent and exhaustion of prostate cancer stem cells.