. Author manuscript; available in PMC: 2020 Jul 1.

Published in final edited form as: NMR Biomed. 2019 May 7;32(7):e4101. doi: 10.1002/nbm.4101

Table 1.

MR parameters (mean ± SEM, unless otherwise specified).

ID	tumor volume (cm³)	R₂ (s⁻¹)	R₁ (s⁻¹)		ΔR₁ (s⁻¹)	BOLD responsive fraction (%)	ΔR₂^* (s⁻¹)		T₁w ΔSI (% baseline)
		air	air	challenge ^c	challenge – air ^d		challenge − air		challenge − air
		air	air	challenge ^c	challenge – air ^d		responsive ^d	nonresponsive ^d	responsive ^d	nonresponsive ^d
small subcutaneous tumors with gbc16 (n = 8)
1	0.2	13.3 ± 0.2	0.525 ± 0.003	0.512 ± 0.003^**	−0.013 ± 0.001^***	62	4.5 ± 0.5^***	0.3 ± 0.1^*	−3.5 ± 0.4^***	−4.5 ± 0.4^***
2	0.4	12.8 ± 0.1	0.496 ± 0.002	0.513 ± 0.002^***	0.017 ± 0.001^***	77	3.7 ± 0.2^***	0.8 ± 0.2^**	−1.3 ± 0.3^***	−2.2 ± 0.3^***
3^a	0.5	13.3 ± 0.1	0.516 ± 0.003	0.520 ± 0.003	0.004 ± 0.002	78	8.0 ± 0.7^***	−0.3 ± 0.2	0.2 ± 0.5	−1.8 ± 0.8
4^b	0.8	11.9 ± 0.1	0.471 ± 0.002	0.489 ± 0.002^***	0.017 ± 0.001^***	65	4.1 ± 0.2^***	0.3 ± 0.1^***	−3.2 ± 0.2^***	−3.2 ± 0.2^***
5^b	1.1	8.7 ± 0.1	0.432 ± 0.020	0.408 ± 0.001	−0.023 ± 0.020	46	3.7 ± 0.3^***	0.3 ± 0.1^**	−0.8 ± 0.2^***	0.4 ± 0.1^**
6^a	1.1	11.4 ± 0.1	0.631 ± 0.052	0.587 ± 0.042	−0.026 ± 0.033	57	1.7 ± 0.2^***	0.4 ± 0.2^*	−0.2 ± 0.1	0.0 ± 0.2
7^a	1.3	13.2 ± 0.1	0.488 ± 0.002	0.487 ± 0.001	−0.002 ± 0.001	75	4.6 ± 0.4^***	0.2 ± 0.2	−0.5 ± 0.3	−0.9 ± 0.3^**
8	1.4	12.2 ± 0.1	0.479 ± 0.001	0.481 ± 0.001	0.002 ± 0.001^**	72	4.7 ± 0.2^***	0.5 ± 0.1^***	0.7 ± 0.2^***	−0.1 ± 0.3
group^e	0.8 ± 0.4	12.1 ± 1.5	0.505 ± 0.059	0.500 ± 0.050	−0.003 ± 0.017	66 ± 11	4.4 ± 1.7	0.3 ± 0.3	−1.1 ± 1.5	−1.5 ± 1.7
large subcutaneous tumors with gbc16 (n = 7)
9^b	2.6	16.2 ± 0.1	0.580 ± 0.021	0.541 ± 0.013	−0.039 ± 0.023	67	5.2 ± 0.4^***	−0.1 ± 0.2	2.1 ± 0.3^***	2.8 ± 0.4^***
10^a	2.7	14.2 ± 0.1	0.482 ± 0.001	0.482 ± 0.001	0.000 ± 0.001	38	4.3 ± 0.2^***	0.3 ± 0.1^***	1.1 ± 0.3^***	1.2 ± 0.1^***
11	2.8	14.7 ± 0.1	0.518 ± 0.001	0.536 ± 0.001^***	0.018 ± 0.001^***	65	4.8 ± 0.3^***	0.5 ± 0.1^***	1.2 ± 0.2^***	0.9 ± 0.2^***
12^a	3.4	16.0 ± 0.1	0.517 ± 0.001	0.508 ± 0.001^***	−0.009 ± 0.001^***	53	3.6 ± 0.4^***	0.1 ± 0.1	−0.6 ± 0.3	0.2 ± 0.2
13^b	3.4	11.7 ± 0.1	0.462 ± 0.002	0.488 ± 0.002^***	0.026 ± 0.002^***	85	5.8 ± 0.2^***	−0.2 ± 0.3	−0.4 ± 0.2	−2.0 ± 0.4^***
14^a	4.0	14.4 ± 0.1	0.511 ± 0.010	0.508 ± 0.010	−0.0032 ± 0.0004^***	61	1.6 ± 0.2^***	0.0 ± 0.1	−0.3 ± 0.2	−0.2 ± 0.1
15	5.1	9.9 ± 0.1	0.430 ± 0.002	0.458 ± 0.002^***	0.027 ± 0.001^***	21	3.4 ± 0.2^***	0.25 ± 0.04^***	6.3 ± 0.4^***	6.9 ± 0.1^***
group^e	3.4 ± 0.9	13.9 ± 2.3	0.500 ± 0.048	0.503 ± 0.030	0.003 ± 0.023	56 ± 21	4.1 ± 1.4	0.1 ± 0.2	1.4 ± 2.4	1.4 ± 2.8
small subcutaneous tumors with gbc100 (n = 3)
3	0.7	13.9 ± 0.1	0.530 ± 0.001	0.535 ± 0.001^*	0.005 ± 0.001^***	63	−4.0 ± 0.2^***	−1.1 ± 0.2^***	2.2 ± 0.2^***	2.0 ± 0.2^***
6	0.8	11.8 ± 0.1	0.484 ± 0.002	0.507 ± 0.002^***	0.022 ± 0.001^***	75	−1.0 ± 0.3^**	−0.1 ± 0.1	5.5 ± 0.2^***	5.7 ± 0.4^***
7	1.1	14.0 ± 0.1	0.497 ± 0.001	0.536 ± 0.002^***	0.039 ± 0.001^***	86	−2.0 ± 0.4^***	−0.1 ± 0.3	5.0 ± 0.4^***	3.3 ± 0.5^***
group^e	0.9 ± 0.2	13.3 ± 1.3	0.504 ± 0.024	0.526 ± 0.017	0.022 ± 0.017	75 ± 11	−2.4 ± 1.5	−0.4 ± 0.6	4.2 ± 1.8	3.6 ± 1.9
large subcutaneous tumors with gbc100 (n = 3)
9	2.7	15.0 ± 0.1	0.517 ± 0.015	0.584 ± 0.022^*	0.067 ± 0.025^**	83	−8.6 ± 0.2^***	−0.2 ± 0.2	11.2 ± 0.3^***	9.9 ± 0.5^***
13	3.0	10.7 ± 0.1	0.480 ± 0.013	0.469 ± 0.003	−0.011 ± 0.012	66	−1.9 ± 0.2^***	−0.4 ± 0.1^**	4.3 ± 0.3^***	3.2 ± 0.2^***
15	4.5	9.0 ± 0.1	0.413 ± 0.008	0.416 ± 0.001	0.004 ± 0.007	33	−2.3 ± 0.1^***	−0.13 ± 0.03^***	3.5 ± 0.1^***	2.2 ± 0.1^***
group^e	3.4 ± 1.0	11.6 ± 3.1	0.470 ± 0.053	0.490 ± 0.086	0.020 ± 0.042	61 ± 25	−4.3 ± 3.8	−0.2 ± 0.2	6.3 ± 4.2	5.1 ± 4.2
orthotopic tumors in lower mammary fat pad with gbc16 (n = 7)
16^a	2.5	22.7 ± 0.3	0.98 ± 0.17	1.28 ± 0.20	0.19 ± 0.17	29	10.5 ± 0.8^***	0.8 ± 0.6	1.0 ± 1.0	−1.9 ± 0.5^***
17	2.9	10.7 ± 0.1	0.95 ± 0.10	1.08 ± 0.12	0.07 ± 0.09	8	13.3 ± 1.8^***	0.2 ± 0.3	1.1 ± 1.7	−2.7 ± 0.4^***
18^a	3.1	22.5 ± 0.4	0.69 ± 0.09	0.65 ± 0.08	−0.04 ± 0.08	12	12.6 ± 2.6^***	0.4 ± 0.4	−6.1 ± 1.5^***	−3.1 ± 0.5^***
19	3.1	14.5 ± 0.2	0.433 ± 0.004	0.470 ± 0.003^***	0.037 ± 0.004^***	20	8.5 ± 1.1^***	1.6 ± 0.2^***	1.3 ± 1.3	−2.7 ± 0.5^***
20^a	4.8	17.2 ± 0.2	1.10 ± 0.14	0.96 ± 0.12	−0.13 ± 0.09	24	7.6 ± 0.9^***	1.6 ± 0.3^***	−0.5 ± 1.0	−0.7 ± 0.5
21	4.8	12.7 ± 0.2	0.53 ± 0.04	0.47 ± 0.01	−0.06 ± 0.04	14	8.2 ± 1.2^***	1.4 ± 0.5^**	−4.3 ± 1.2^**	−0.8 ± 0.6
22^a	5.9	14.8 ± 0.2	0.75 ± 0.08	0.73 ± 0.08	−0.02 ± 0.08	15	10.4 ± 1.7^***	1.0 ± 0.3^***	3.0 ± 1.5^*	−2.0 ± 0.4^***
group^e	3.9 ± 1.3	16.4 ± 4.7	0.78 ± 0.25	0.81 ± 0.31	0.01 ± 0.10	66 ± 12	10.2 ± 2.2^***	1.0 ± 0.5	−0.6 ± 3.3	−2.0 ± 0.9

a & b: Histology and immunohistochemical assessment of hypoxia (using pimonidazole) was conducted within 24 hr post MRI.

: The rat breathed air with respect to pimonidazole injection.

: The rat breathed 16% O₂ with respect to pimonidazole injection.

: Unpaired t-tests (challenge vs. baseline) for each tumor.

: Paired t-tests (challenge vs. baseline) for each tumor.

: Group mean ± SD.

p < 0.05

^**

p < 0.01

^***

p < 0.001.