Figure 8. Representative images of the HBEC (normal human bronchial epithelial cells) -CDC6 Tet ON cellular model, grown in 3D organotypic conditions and stained for H-E (hematoxylin-eosin). The epithelial origin of HBECs is similar to various other cancer types, and in their un-induced state [(A) “OFF” state], they lack mutations found in cancer cells. This 3D organotypic model allows the precise and reliable detection of amassing DNA alterations during CDC6-induced senescence [(B) “ON” state] (23).