In humans every minute millions of cells die by programmed cell death and by the end of their life almost 99.9% of all cells once made have undergone this fate [1]. The functionality of cell death is different during development and adult life. During development apoptosis serves three major functions: deleting vestigial structures, i.e. phylogenetic cell death; controlling cell numbers, i.e. histogenetic cell death, and remodeling structures, i.e. morphogenetic cell death [2]. In adult life, apoptosis mainly serves to maintain homeostasis by counterbalancing mitosis and deleting cells, which are potentially autoimmunoreactive, malignant, or virus infected [3,4].