¹¹C-Labeled Pictilisib (GDC-0941) as a Molecular Tracer Targeting Phosphatidylinositol 3-Kinase (PI3K) for Breast Cancer Imaging

Table 2

Biodistribution of [¹¹C]-pictilisib in BALB/C nude mice bearing MCF-7 and MDA-MB-231 xenografts (%ID/g mean ± SD).

Organ (%ID/g)	MCF-7 (n = 3)			MDA-MB-231 (n = 3)
	10 min	30 min	60 min	10 min	30 min	60 min
Blood	2.99 ± 0.32	1.69 ± 0.28	1.40 ± 0.22	3.66 ± 1.40	1.09 ± 0.58	1.15 ± 0.18
Brain	0.70 ± 0.10	0.57 ± 0.04	0.23 ± 0.22	1.06 ± 0.29	0.44 ± 0.03	0.35 ± 0.03
Liver	38.49 ± 5.71	27.98 ± 1.61	23.42 ± 0.93	45.28 ± 10.99	25.37 ± 5.35	16.19 ± 2.33
Spleen	8.20 ± 1.94	3.43 ± 0.46	2.26 ± 0.26	6.15 ± 0.91	3.14 ± 0.54	1.92 ± 0.27
Kidney	9.82 ± 0.82	5.41 ± 0.22	4.56 ± 0.25	12.59 ± 3.73	5.19 ± 0.87	3.25 ± 0.45
Stomach	5.22 ± 1.33	5.71 ± 0.83	4.12 ± 1.25	5.46 ± 2.01	4.11 ± 1.55	2.45 ± 0.32
Sm. int	12.32 ± 2.09	13.93 ± 1.05	29.59 ± 4.98	15.57 ± 9.66	22.37 ± 9.50	23.81 ± 1.77
Colon	4.15 ± 0.91	3.65 ± 1.31	2.79 ± 0.29	5.89 ± 2.3	2.51 ± 0.20	3.14 ± 1.18
Muscle	1.35 ± 0.10	1.10 ± 0.37	0.74 ± 0.04	1.74 ± 0.35	1.35 ± 0.48	1.00 ± 0.15
Bone	2.33 ± 0.35	0.98 ± 0.81	0.73 ± 0.27	3.86 ± 0.66	1.41 ± 0.26	0.89 ± 0.21
Tumor	1.72 ± 0.38	2.31 ± 0.12	2.88 ± 0.07	1.90 ± 0.62	0.98 ± 0.32	1.15 ± 0.26
Uptake ratio
Tumor-to-blood	0.59 ± 0.18	1.41 ± 0.28	2.11 ± 0.34	0.60 ± 0.31	1.17 ± 0.52	1.01 ± 0.21
Tumor-to-muscle	1.30 ± 0.36	2.41 ± 0.91	3.87 ± 0.20	0.83 ± 0.05	0.74 ± 0.09	1.15 ± 0.15