Figure 2.

A Model of Carcinogenesis, adapted from Gillies & Gatenby (2007). Carcinogenesis is presented with tumorigenic barriers and proposed timing of hallmark events.^2,4 The specific order of occurrence for each carcinogenic hallmark may differ from cancer to cancer. Although not originally listed as a hallmark event, diminished DNA repair is included here because it can be considered a necessary step for subsequent carcinogenesis.