TK1 and cancer: TK-1 overexpression is similarly observed in cancer models,30,31 and its association with the Ki67 proliferation index has been demonstrated in various cancers.32-34 Interestingly, AAA [18F]FLT uptake was observed after 14 days of AngII infusion, when aneurysms expand, but this effect was weaker after 28 days, when the growth phase begins to plateau, suggesting decreased cell proliferation in late-stage AAA.