Application of Multiparametric Magnetic Resonance Imaging to Monitor the Early Antitumor Effect of CuS@GOD Nanoparticles in a 4 T1 Breast Cancer Xenograft Model

Background We have developed hybrid nanoparticles (NPs) by co‐loading copper sulfide (CuS) NPs and glucose oxidase (GOD) (CuS@GOD NPs) to explore their antitumor properties. Purpose To investigate the feasibility of using multiparametric magnetic resonance imaging (MRI) including intravoxel incoherent motion diffusion‐weighted imaging (IVIM‐DWI) and R 2 * mapping to quantitatively assess the early antitumor effect of CuS@GOD NPs. Study type Prospective. Animal model The orthotopic BALB/c mice 4 T1 breast cancer model. The 4 T1 xenografts in group 1 mice received normal saline, group 2 received CuS@GOD NPs, group 3 received CuS NPs plus laser, and group 4 received CuS@GOD NPs plus laser ( n = 28 for each group). Field Strength/Sequence A 3.0 T/IVIM‐DWI MRI single‐shot echo‐planar imaging, R 2 * mapping spoiled gradient recalled echo (SPGR) sequence, T2‐weighted images (T2WI) and T1‐weighted images (T1WI) fast spin echo (FSE) sequence. Assessment The IVIM‐DWI and R 2 * mapping were performed before and after treatment at 0 hour, 0.5 hour, 1 hour, 2 hours, 4 hours, and 24 hours in four groups and the MRI parameters were obtained. Correlation analysis between the MRI parameters and histological analyses was conducted. Statistical Tests One‐way ANOVA, Pearson's correlation analysis, two independent samples t test, intraclass correlation coefficient. P < 0.05 was considered to be statistically significant. Results In group 4, the tumoral D value was significantly higher than that of group 2 at 24 hours (0.541 ± 0.065 vs. 0.492 ± 0.051). The f value of group 4 was significantly lower than that of groups 1 and 2 at 2 hours (10.83 ± 2.16 vs. 14.28 ± 1.86, 16.67 ± 3.53, respectively). The R 2 * value was significantly increased at 0 hour in group 4 compared to that of groups 1 and 2 (64.552 ± 4.663 vs. 42.441 ± 1.516, 43.165 ± 1.709, respectively). D, f, and R 2 * were correlated with the histological staining results ( r = 0.695–0.970). Data Conclusion The IVIM‐DWI‐derived D and f and R 2 * mapping‐derived R 2 * could monitor early response to CuS@GOD NPs treatment in vivo. Evidence Level 2 Technical Efficacy Stage 2