| Objective:To explore the value of 99Tcm-3PRGD2 in accessing response to rh-endostatin in Lewis lung carcinoma tumor bearing mice.Methods: 1 Cell culture and animal building The lewis lung carcinoma?LLC?cells were incubated largely by standing andherent.LLC cells were harvested and trypsinezed,a single suspension containing 1.0×107 cells was prepared in a total volume of 1ml.LLC mice model was established by subcutaneous injection of 2.0 × 106 LLC cells into the right rear legs of C57BL/6J mice.The mice with tumor size of 1.0cm were chosed for study.2 The experimental group and intervention After about 2 weeks,LLC tumor bearing mice with the tumor size of 1.0cm were randomly assigned to two groups?n=36 per group?:treatment group and control group.Then treatment group or control group were randomly assigned to two groups:treatment 99Tcm-3PRGD2 imaging group?TRGD group?,treatment 99Tcm-MIBI imaging group?TMIBI group?,control 99Tcm-3PRGD2 imaging group?CRGD group?,control 99Tcm-MIBI imaging group?CMIBI group?.TRGD group and CRGD group were difined RGD group,TMIBI group and CMIBI group were defined MIBI group.The mice in treatment group were injected with Endostar intraperitoneally,Endostar to give a dose of 8 ?g/g?0.008ml/g?,and 0.9% saline was used in the control group.The body weight of mice were measured everyday with digital calipers.3 SPECT scan and image analyses SPECT scan and image analyses were performed at 1h after 99Tcm-3PRGD2 or 2h after 99Tcm-MIBI injection in the tail vein on the 3th,7thand 14 th of Endostar treatment.Regions of interests?ROI?were drawn over the tumor and the contralateral areas for comparing T/NT five times,and the average value was defined as the result.4 Immunohistochmical staining After scan,heart perfusion were performed,the tumors were taken out from the mice,measured by the diameter.The morphology of xenografts were observed by HE staining,Integrin ???3 and Ki67 expression of the tumors was analyzed by immunohistochmical staining?IHC?.5 Data analysis SPSS21.0 were used for data analysis.Quantitative data were expressed as the mean ± SD or median?quartile range?.Date between groups were compared using t-test or wilcoxon rank sum test,date in each group were analized using One-Way ANOVA.T/NT ratio correlation with the expression of ???3?Ki67 were analized using Spearman correlation analysis,P values <0.05 were considered statistically significant.Results: 1 The rate of tumor formation was 100%.2 The weight of the mice in the treatment group and the control group during the treatment were increased to varying degrees,the difference was not statistically significant?t=-0.868,P=0.389?.3 During treatment,tumor volumes of mice gradually increased in each group,but the growth rate of the treatment group is lower than the control group.There was statistical difference between treatment group and control group in the tumor volumes.?Z=-1.995,P =0.046?.4 The imaging of 99Tcm-3PRGD2 or 99Tcm-MIBI in the tumor bearing mice the CRGD group showed obvious radioactivity concentration in the tumor site.On the third and seventh day of the TRGD group,the radioactivity of the tumor site was stronger than that of the contralateral tissue,and the tumor site was sparse on fourteenth day.The radioactivity in the soft tissues of the chestwere uniform,and the radioactivity of the kidney and the bladder is radioactive.The tumor sites showed radioactive defectsin TMIBI group and CMIBI group.In the later period,with the increase of tumor,the area of radioactivity defect increased.The soft tissue of the background can be uniformly absorbed with the imaging agent,and the gastrointestinal tract of the abdominal cavity appears to be radioactive concentrated.5 The change of T/NT ratio in 99Tcm-3PRGD2 or 99Tcm-MIBI imaging The T/NT ratio in TRGD group on the 3th?7th?14th day?2.25±0.15?1.75±0.09?0.85±0.25?were lower than that in CRGD group?2.32±0.12?3.17±0.14?3.30±0.05?,there was no statistical difference in T/NT ratio on the 3th day of treatment?t=-0.943,P =0.368?,but there were significant statistical on 7th?14th?t?t'?=-20.705?-43.797,P=0.000,0.000?;In the TRGD group,there were significant statistical difference in the T/NT ratio of the 3th?7th?14th day?P=0.000,0.000,0.000?.In the CRGD group,there were significant statistical difference between the 3th day and the 7th or 14 th day?P=0.0003-7,0.0003-14?,there was no significant statistical difference between the7 th day and the 14th?P=0.0967-14?.The T/NT ratio of TMIBI group on the 3th?7th?14th day?1.01±0.04?0.82±0.06?0.52±0.08?were similar with that in CMIBI group?1.0±0.04?0.84±0.08?0.53±0.09?,there was no statistical difference?P>0.05?.In the TMIBI group,there were significant statistical difference in the T/NT ratio of the 3th?7th?14th day?P=0.000,0.000,0.000?.In the CMIBI group,there were significant statistical difference in the T/NT ratio of the 3th?7th?14th day?P=0.0203-7,0.0007-14,0.0003-14?.6 The expression of HE and integrin receptor ?v?3,proliferating cell nuclear antigen Ki67 were observed under microscope HE staining revealed that the high density of tumor cells and atypia in control group,the treatment group showed different degrees of tissue necrosis with inflammatory cell infiltration.Immunohistochemical staining showed thatthe intergrin ?v?3 and Ki67 were expressed both in two groups.With the increase of treatment days,the proportion of positive cells in the treatment group decreased gradually,while the proportion of positive cells increased in the control group.7 The positive expression of integrin receptor ?v?3 and proliferating nuclear antigen Ki67 The percents of Ki67 proliferation index on the 3th?7th?14th day were 0.680±0.050 ? 0.420?0.385-0.445?? 0.360?0.310-0.378?in treatment group;While the Ki67 proliferation index on the 3th?7th?14th day were 0.740±0.040?0.735?0.675-0.780??0.710?0.660-0.720?in control group.There were significant difference in two groups?Z=-5.449,P<0.010?.The percents of ?v?3 positive cells on the 3th?7th?14th day were 0.540±0.025?0.410±0.040?0.330?0.305-0.375?in treatment group,While the percents of ?v?3 positive cells on the 3th ? 7th ? 14 th day were 0.600?0.580-0.630??0.680?0.623-0.700??0.730?0.700-0.770?.There were significant difference in two groups?Z=-6.189,P<0.01?.8 The Correlation Analysis between the T/NT ratio and the expression of ?v?3?Ki67 The T/NT ratio and the expression of ?v?3?Ki67 showed positively correlated in the RGD group?r=0.934,P=0.000;r=0.721,P=0.000?;While there were no significant correlation in the MIBI group?r=0.048,P=0.783;r=0.307,P=0.068?.Conclusions: 1 99Tcm-3PRGD2 imaging in tumor bearing mice showed higher target / non target ratio comparing with nonspecific tumor imaging agent 99Tcm-MIBI,and it can be used to monitor tumor early response to antiangiogenic therapy.2 99Tcm-MIBI SPECT imaging in tumor bearing mice showed radioactivity defect,there were some limitations in the diagnosis andevaluation of some chest tumors,which can be supplemented by 99Tcm-3PRGD2 SPECT imaging. |
PDF Full Text Request