Application of Dynamic Contrast-Enhanced MRI in the Therapeutic Evaluation of the Chinese Medicine Kanglaite in Treating Colorectal Cancer

Abstract

Background: Magnetic resonance imaging (MRI) can provide a reference for tumor treatment and its quantitative parameters can serve as imaging indicators that reflect tumor angiogenesis and vascularity. Kanglaite (KLT) has therapeutic effects on cancers. In this study, DCE-MRI was used to investigate its application in evaluating KLT anti-colorectal cancer. Objectives: Evaluating the efficacy of Kanglaite (KLT) injection for treatment of colorectal cancer with dynamic contrast-enhanced MRI (DCE-MRI) parameters. Methods: This study was an experimental study. The 20 successfully modeled nude mice were randomly assigned to 2 groups: blank control group (n = 10) and the KLT injection group (n = 10). The research protocol was approved by the ethics committee of the second affiliated hospital of Xinjiang medical university (protocol NO: 20140216-12) in 2015. A subcutaneous xenograft colorectal tumor model was subjected to KLT treatment. DCE-MRI obtain the parameters including Ktrans, Ve, Kep, Vp, immunohistochemical staining measure microvascular density (MVD), levels of vascular endothelial growth factor (VEGF), and proliferating cell nuclear antigen (PCNA). Results: Compared to the blank control, the volume of tumor in the KLT group markedly reduced by 49%. 48 hours after, compared to the blank control, the Ktrans (0.028 ± 0.009 vs 0.012 ± 0.006), Ve (0.312 ± 0.089 vs 0.287 ± 0.037), and Kep values (0.321 ± 0.056 vs 0.577 ± 0.033) decreased in KLT group (P < 0.05). In contrast, the Vp value (0.094 ± 0.037 vs 0.043 ± 0.017) was significantly elevated in the KLT group (P < 0.05). There is a correlation between Ktrans, Kep and VEGF score, MVD count, and PCNA score. Conclusions: The parameters of DCE-MRI may be used as imaging biomarkers for assessing the status of tumor-bearing vasculatures and provide a basis for evaluating the efficacy of anti-tumor drugs.