Multiple cell death programs: Charon's lifts to Hades

Cells use different pathways for active self‐destruction as reflected by different morphology: while in apoptosis (or “type I”) nuclear fragmentation associated with cytoplasmic condensation but preservation of organelles is predominant, autophagic degradation of cytoplasmic structures preceding nuclear collapse is a characteristic of a second type of programmed cell death (PCD). The diverse morphologies can be attributed – at least to some extent – to distinct biochemical and molecular events (e.g. caspase‐dependent and ‐independent death programs; DAP‐kinase activity, Ras‐expression). However, apoptosis and autophagic PCD are not mutually exclusive phenomena. Rather, diverse PCD programs emerged during evolution, the conservation of which apparently allows cells a flexible response to environmental changes, either physiological or pathological.