ABSTRACT
Objective To investigate the value of molecular probe USPIO-PEG-sLeX in metastasis model of nasopharyngeal carcinoma. Methods According to the pathological results of transplanted tumors of nude mice with nasopharyngeal carcinoma,the tumor-bearing mice were divided into metastatic group and non-metastatic group.T2 ? values of the transplanted tumors at four different time points were measured before and after the injection of USPIO-PEG-sLeX(t0＝plain scan,t1＝scan immediately after enhancement,t2＝1 hour post-enhancement scan,t3＝2 hours post-enhancement scan).ΔT2 ? and enhancing rates at t1 ,t2,t3 were calculated.Results The plain T2 ? values of the metastatic group and the non-metastatic group were 22.25±8.08 and 27.01±9.45,respectively.There was no significant difference between the two groups at t0 (P＞0.05).The T2 ? values at t1,t2 and t3 were 11.57±4.02 and 24.82±7.84,10.09±4.88 and 24.15±8.74,12.46±5.63,23.42±7.12 respectively in the metastatic and non-metastatic groups,differences were statistically significant (P values were 0.005,0.008 and 0.01 9,respectively).ΔT2 ? values at time t1 ,t2 and t3 in nude mice in the metastatic and non-metastatic groups were 10.69±6.23,3.86±2.20,12.1 7±8.67 and 2.87±1.37,9.80±3.03,4.32±2.28 respectively.The differences were statistically significant (P values were 0.027,0.048 and 0.043,respectively).The enhancement rates at t1,t2 and t3 in nude mice in metastatic and non-metastatic groups were 45.98±14.03,7.10±5.18,5 1.1 5±22.70 and 1 1.04±6.01 ,44.05 ±13.92,12.09 ±7.54,respectively,with statistically significant differences (P values were 0.001,0.005 and 0.007,respectively).After two-way repeated-measures analysis of variance,there was a statistically significant difference in T2 ? values between the metastatic and non-metastatic groups (P＝0.02＜0.05).There was a statistically significant difference in T2 ? values at different times (P＝0.001＜0.05).There was an interaction between the metastatic and non-metastatic groups and the scan time (P＝0.043＜0.05).Conclusion USPIO-PEG-sLeX molecular probe can non- invasively monitor E-selectin expression,and has a good application prospect in monitoring the metastasis of nasopharyngeal carcino-ma xenograft models.
ABSTRACT
Objective To trace human umbilical cord mesenchymal stem cells (MSCs)labelled by USPIO-PLL which were transplanted into mouse subcutaneous xenotransplanted lung cancer by using 3.0T MR,to investigate the relationship between MSCs and VEGF expression and tumor angiogenesis by using SABC immunohistochemical method and to comprehensively analyze the effect of MSCs transplantation on lung cancer.Methods Cultured MSCs and poly lysine (PLL)was as a transfection agent which was magnetically labeled by USPIO and implanted into mice with subcutaneous xenotransplanted lung cancer through the tail vein.MRI was performed at pre-transplantation, 1 d and 10 d after transplantation and the tissues were performed by immunohistochemistry respectively.Results (1)MSCs could reach the tumor area at the first day after the transplantation and be monitored by MRI.MSCs increased at the 10th day.MRI signal intensity was reducedand the difference was statistically significant (P <0.05).The inhibitory rate of the 1st day and 10th day was positive;(2)At the 10th day after the transplantation,the rate of the VEGF positive expression in MSCs group was 86.67％,the value of MVD was 44 .22 ± 12 .36 ,and the rate of the VEGF positive expression in NS group was 26 .67 ％ ,the value of MVD was 20 .29 ±8.47 (P <0.05).Conclusion Tracing stem cell transplantation in vivo can be proceeded effectively by using 3.0T MR.Stem cell has bidirectional effect on lung cancer which inhibites the tumor growth by directional chemotaxis and differentiation,and also enhances expression of VEGF and angiogenesis at a certain extent.
ABSTRACT
Objective To trace human umbilical cord mesenchymal stem cells (MSCs)labelled by USPIO-PLL which were transplanted into mouse subcutaneous xenotransplanted lung cancer by using 3.0T MR,to investigate the relationship between MSCs and VEGF expression and tumor angiogenesis by using SABC immunohistochemical method and to comprehensively analyze the effect of MSCs transplantation on lung cancer.Methods Cultured MSCs and poly lysine (PLL)was as a transfection agent which was magnetically labeled by USPIO and implanted into mice with subcutaneous xenotransplanted lung cancer through the tail vein.MRI was performed at pre-transplantation, 1 d and 10 d after transplantation and the tissues were performed by immunohistochemistry respectively.Results (1)MSCs could reach the tumor area at the first day after the transplantation and be monitored by MRI.MSCs increased at the 10th day.MRI signal intensity was reducedand the difference was statistically significant (P <0.05).The inhibitory rate of the 1st day and 10th day was positive;(2)At the 10th day after the transplantation,the rate of the VEGF positive expression in MSCs group was 86.67％,the value of MVD was 44 .22 ± 12 .36 ,and the rate of the VEGF positive expression in NS group was 26 .67 ％ ,the value of MVD was 20 .29 ±8.47 (P <0.05).Conclusion Tracing stem cell transplantation in vivo can be proceeded effectively by using 3.0T MR.Stem cell has bidirectional effect on lung cancer which inhibites the tumor growth by directional chemotaxis and differentiation,and also enhances expression of VEGF and angiogenesis at a certain extent.
ABSTRACT
Objective To investigate the imaging characteristics of USPIO-enhanced and Gd-enhanced MRI in atherosclerosis and to compare the detection rate of atherosclerotic plaque between them. Methods Thirty-five healthy male rabbits were assigned to experimental group (n=30) to establish a model of atherosclerosis by damaging aortic tunica intima with Foley′s tube in combination with a high fat diet and 5 to control group without any intervention. At week 12, USPIO-enhanced and Gd-enhanced MRI scanning were conducted to compare the signal changes of atherosclerotic plaque before and after enhancement with the 2 contrast media. Ninety seven pictures were randomly selected respectively from the pictures enhanced by the 2 contrast media to compare the detection rate plaque between them. Pthology examination was used for detection standard. For the control group , pictures were randomly selected. Results In the experimental group, 7 rabbits died of Foley′s tube damaging, 2 died of raising and 1 died of anesthesia. All 5 rabbits in control group survived. A total of 172 pathological sections were made with 134 plaques and 72 vulnerable plaques pathologically confirmed. In pictures enhanced by USPIO , 84 plaques were confirmed by HE staining with a detection rate of 86.6%. In pictures enhanced by Gd, 72 plaques were confirmed by HE staining with a detection rate of 74.2%. Detection rate of USPIO-enhanced MRI in atherosclerosis plaque was significantly higher than that of Gd-enhanced MRI (X2=3.96, P=0.046). Conclusion USPIO shows its superiority as a new contrast medium in detection of atherosclerosis plaque.