Figure 4.

Differential dynamics of a cell cycle ODE model [41] in normal and cancer states. a) List of the cell cycle models that involve the cyclin D, which is often over-expressed in breast cancer cells; the model chosen for the simulation is indicated by the blue arrow. I) Normal cell cycle dynamics are characterised by a timed activation of the transcription factor E2F and the following activation of cyclin E in its active form (CycEa). c) Breast cancer state: according to the breast cancer associated up-regulation of cyclin D, its synthesis rate is increased, determining an earlier entrance into the S phase, with the early activation of the transcription factor E2F from which the cyclin E synthesis depends; such events determine a faster cell cycle progression allowing a more efficient tumour proliferation.