Based on % injected dose/g, tumour uptake of 18F-ICMT-11 was 2.2-fold higher after doxycycline-induced caspase-3 activation compared with respective controls, which was significant (p < 0.01, Student’s t test; p = 0.02, two-way ANOVA and Sidak’s multiple comparisons tests (Fig. 4a), whereas the tumour uptake of 18F-ML-10 was not significantly altered after doxycycline administration (Fig. 4b). This evidence concerns the gene CASP3 and neoplasm.