磁共振弥散成像对耐药与不耐药结肠癌荷瘤鼠检测的观察

Detection of the drug resistance of human colon cancer in mice with magnetic resonance diffusion-weighted imaging

目的 :探索磁共振弥散成像(MR-DWI)活体检测结肠癌耐药性的可能性。方法 :对耐药组与不耐药组人类结肠癌SW480荷瘤裸鼠(各5只)的肿瘤行MR-DWI检查,随后处死荷瘤鼠、切下肿瘤检测肿瘤的PKC、P-gp、MRP1蛋白表达(Western Blot),组织切片观察(HE染色);对比分析两组荷瘤鼠肿瘤MR-DWI的ADC值及蛋白表达和组织切片改变。结果:不耐药人类结肠癌SW480组裸鼠模型肿瘤边缘及中心ADC值均较耐药人类结肠癌SW480/5-FU组裸鼠模型增高,不耐药人类结肠癌SW480组裸鼠模型肿瘤边缘ADC值与耐药人类结肠癌SW480/5-FU组裸鼠模型肿瘤边缘ADC值的差别具有统计学意义(P<0.05),肿瘤中心ADC值差别则无统计学意义(P>0.05);肿瘤的ADC值与耐药性呈负相关。耐药组PKC、P-gp、MRP1蛋白表达明显高于不耐药组,差别有统计学差异(P<0.05)。结论:MR-DWI检测的ADC值变化有可能有助于利用MR活体检测结肠癌耐药性。

Objective： To investigate the possibilities in detecting the drug resistance of human colon cancer with MR diffusion-weighted imaging（MR-DWI）. Methods： SW480（drug response） and SW480/5-FU（5-FU resistance） human colon cancer-bearing nude mice（five each group） were given MR-DWI examinations. Then these mouse models were sacrificed. Their tumors were removed for PKC, P-gp, MRP1 protein expression（Western Blot）, and tissue sections（HE staining） was observed.ADCs of the tumor in tumor-bearing mice of two groups were analyzed in comparison with PKC, P-gp, MRP1 protein expression and changes in tissue sections. Results： The values of apparent diffusion coefficient（ADC） detected in the center and edge of the tumor in SW480 group were higher than those in SW480/5-FU group. There was statistical difference（P〈0.05） of ADC value in the edge of tumor between SW480 group and SW480/5-FU group, and there was no statistical difference（P〉0.05）of ADC value in the center of tumor between two groups. ADC value of tumor was negatively correlated with drug resistance.PKC, P-gp, MRP1 protein expression of SW480/5-FU group were significantly higher than that of SW480 group（P〈0.05）. Conclusions： MR-DWI ADC value change has the potential to help detection of colon cancer drug resistance with MR in vivo.