CDK4 and tuberous sclerosis: Canonical WNT signalling induces tumour stem cell (TSC) proliferation through direct upregulation of CCND1 and MYC and secondary upregulation of CCNA2, CCNB1, CCND2, CCND3, CCNE2 and CDK4, whereas noncanonical WNT signalling induces a dormant TSC mode through inhibition of canonical WNT signalling and cross-talk with TGFβ signalling [6].