低强度超声诱导微泡空化联合血凝酶、恩度靶向协同抑制肿瘤生长的实验研究

Experimental study on synergistic inhibition of tumor growth by microbubble cavitation induced by low intensity ultrasound combined with hemocoagulase and Endostar

目的:采用低强度超声诱导微泡空化联合血凝酶靶向阻断肿瘤微小血管,同时注射靶向药物恩度(重组人血管内皮抑制素注射液)抑制肿瘤新生血管,探讨物理干预和化疗药物治疗协同抑制肿瘤生长的作用。方法:75只荷人源肺腺癌雄性BALB/c-nu/nu小鼠,体重25~30 g,随机分为低强度超声空化+恩度(MEUC+Endostar)组、低强度超声空化+血凝酶+恩度(MEUC+HC+Endostar)组、低强度超声空化(MEUC)组、恩度(Endostar)组和假照组,每组15只。连续给予相应治疗干预4 d后再无菌饲养4 d,干预前、干预后即刻和干预后4 d分别进行二维B超扫描和超声造影(CEUS),随即获取肿瘤组织进行血管内皮生长因子免疫荧光染色,观察微血管密度(MVD)。结果:干预前各组肿瘤体积差异无统计学意义(P>0.05),干预后即刻和干预后4 d,MEUC+HC+Endostar组肿瘤体积明显小于其他各组(P<0.05)。干预前各组肿瘤CEUS灌注良好,PI和AUC差异均无统计学意义(P>0.05),干预后即刻,MEUC+Endostar组、MEUC+HC+Endostar组、MEUC组肿瘤内可见充盈缺损区,Endostar组、假照组充盈良好;干预后4 d,MEUC+Endostar组、MEUC+HC+Endostar组充盈缺损区仍然存在,而MEUC组可见部分血流灌注恢复,PI和AUC在MEUC+HC+Endostar组仍显著低于其他各组(P<0.05)。干预后4 d获取肿瘤组织,MEUC+HC+Endostar组的MVD显著低于其余各组,肿瘤组织MVD差异有统计学意义(P<0.05)。结论:低强度超声诱导微泡空化联合血凝酶、恩度靶向阻断肿瘤微小血管和抑制肿瘤新生血管形成中产生协同作用,可更有效地抑制肿瘤生长。

Objective To investigate the synergistic effect of physical intervention and chemotherapeutic drug therapy on tumor growth by blocking tumor microvessels and injecting chemotherapy drug Endostar(ecombinant human vascular endostatin injection)to inhibit tumor neovascularization by low intensity ultrasound induced microbubble cavitation combined with hemocoagulase.Methods Seventy-five male NU/NU mice bearing human-derived lung adenocarcinoma,weighing 25-30 g,were randomly divided into microbubble-enhanced ultrasonic cavitation+Endostar group(MEUC+Endostar),microbubble-enhanced ultrasonic cavitation+hemocoagulase+Endostar group(MEUC+HC+Endostar),microbubble-enhanced ultrasonic cavitation(MEUC),Endostar group(Endostar)and sham group.Fifteen mice in each group were given the corresponding treatment intervention for 4 consecutive days followed by 4 days of aseptic feeding.Two-dimensional ultrasound and contrast-enhanced ultrasound(CEUS)were performed before intervention,immediately after intervention and 4 days after intervention,respectively.Tumor tissues were obtained for vascular endothelial growth factor immunofluorescence staining,and microvessel density(MVD)was observed.Results There was no difference in tumor volume between the groups before the intervention(P>0.05).Immediately after the intervention,filling defects were observed in MEUC+Endostar group,MEUC+HC+Endostar group and MEUC group,while filling was good in Endostar group and sham group;4 days after the intervention,filling defects were observed in MEUC+Endostar group and MEUC+HC+Endostar group.The filling defect was still present in Endostar group,while partial recovery of perfusion was performed in MEUC group,and PI and AUC were still significantly lower in MEUC+HC+Endostar group than in the other groups(P<0.05).When tumor tissues were obtained 4 days after the intervention,the MVD in MEUC+HC+Endostar group was significantly lower than that in the remaining groups,and the difference of MVD in tumor tissue was statistically significant(P<0.05).Conclusions Low intensity ultrasound induced microbubble cavitation combined with hemocoagulase and Endostar can produce a synergistic effect in blocking tumor microvessels and inhibiting tumor angiogenesis,which can more effectively inhibit tumor growth.