Synthesis and biological characterisation of 18 F-SIG343 and 18 F-SIG353, novel and high selectivity σ 2 radiotracers, for tumour imaging properties

EJNMMI Research

Table 3 Biodistribution of ¹⁸ F-SIG343 and ¹⁸ F-SIG353 in representative tissues (decay corrected)

Compound	Time (min)	Brain	Liver	Spleen	Kidneys	Femur	Lungs	Heart	Blood	Pancreas	Ovaries	Tumour
¹⁸F-SIG343	15	9.6 ± 0.2^***	16.0 ± 0.9^**	14.6 ± 1.2	26.1 ± 0.6	4.5 ± 0.4	30.3 ± 1.2^***	5.5 ± 0.4	0.9 ± 0.1	42.9 ± 2.8^*	10.8 ± 1.8	3.1 ± 0.5
	30	8.8 ± 0.6^***	21.9 ± 0.8^***	15.2 ± 1.1^*	19.8 ± 0.9^***	4.3 ± 0.2	17.4 ± 0.7^***	3.5 ± 0.2^**	0.7 ± 0.04	50.2 ± 2.0^***	14.0 ± 2.2	3.0 ± 0.1^*
	60	7.1 ± 0.4^***	15.2 ± 1.1^***	12.8 ± 0.9^***	12.0 ± 0.6^**	3.8 ± 0.1	9.9 ± 0.3^***	1.9 ± 0.04^**	0.6 ± 0.1	64.4 ± 3.5^***	13.5 ± 2.2	3.5 ± 0.3^*
	120	5.2 ± 0.7^***	19.8 ± 0.9^*	8.5 ± 0.2^***	7.5 ± 0.4	3.2 ± 0.1	5.0 ± 0.3	1.1 ± 0.1	0.4 ± 0.01	61.7 ± 3.4^***	11.5 ± 1.4	3.9 ± 0.2
¹⁸F-SIG353	15	4.4 ± 0.2	23.5 ± 2.0	15.7 ± 1.1	23.4 ± 2.0	5.3 ± 0.3	17.4 ± 0.5	4.5 ± 0.2	1.2 ± 0.03	56.4 ± 4.7	10.0 ± 0.9	3.8 ± 0.3
	30	2.3 ± 0.1	33.0 ± 1.8	12.0 ± 0.6	13.3 ± 0.8	4.7 ± 0.2	8.6 ± 0.4	2.5 ± 0.1	1.0 ± 0.1	72.8 ± 2.4	11.8 ± 1.5	3.8 ± 0.3
	60	1.3 ± 0.01	32.6 ± 1.0	7.7 ± 0.4	8.7 ± 0.3	3.8 ± 0.2	6.1 ± 0.1	1.7 ± 0.02	0.7 ± 0.02	94.3 ± 4.2	9.6 ± 1.5	4.6 ± 0.2
	120	0.8 ± 0.02	24.1 ± 1.4	5.5 ± 0.2	7.1 ± 0.2	3.9 ± 0.1	4.7 ± 0.2	1.3 ± 0.1	0.7 ± 0.03	119.2 ± 1.6	12.2 ± 3.1	4.8 ± 0.4

Data are presented as the means of percentage of injected dose per g of tissue (%ID/g ± SEM, n = 5). Comparisons of ¹⁸F-SIG343 vs. ¹⁸F-SIG353, unpaired two-tailed Student's t test, matched organ and time point. SEM scanning electron microscopy *0.01 < P < 0.05 (significant); **0.001 < P < 0.01 (very significant); ***P < 0.001 (extremely significant).