靶向TEM1蛋白促进细胞毒性药物Sap 对TEM1高表达子宫肉瘤的杀伤作用

TEM1 antibody-conjugated Sap inhibits TEM1-positive human sarcoma cells in vitro and in vivo

关键词:  肉瘤  肿瘤内皮标记物1  皂草毒蛋白  免疫毒性  子宫肉瘤细胞  骨肉瘤细胞  纤维肉瘤细胞HT1080子宫腺癌细胞

Key words:  sarcoma  tumor endothelicial marker  Sap  immunotoxin

摘要:

目的 探讨靶向肿瘤内皮标记物1(tumor endothelial marker 1, TEM1)蛋白的细胞毒性物质皂草毒蛋白(Sap)对TEM1高表达的肉瘤细胞的杀伤作用。方法 流式细胞术检测肉瘤细胞SJSA-1、A673、SAOS-2、HOS、MES-SA、U2OS、SKUT-1、HT1080以及子宫腺癌细胞RL95-2、AN3CA、KLE中TEM1的表达水平；将TEM1抗体与细胞毒性物质Sap的复合物anti-TEM1-Sap以及未结合TEM1抗体的Sap按照浓度梯度作用于细胞,观察对细胞的杀伤作用；建立TEM1阳性的皮下肉瘤动物模型,当肿瘤长至100mm³时,将anti-TEM1-Sap与未结合T1M1抗体的Sap通过尾静脉注射至小鼠,观察两组肿瘤生长情况。结果 4种肉瘤细胞(SJSA-1、A673、HOS和MES-SA)的TEM1 mRNA和蛋白表达为阳性,4种肉瘤细胞HT1080、SAOS-2、U2OS、SKUT-1)和所有腺癌细胞(AN3CA、RL95-2、KLE)均为TEM1表达阴性。TEM1阳性的细胞中,低剂量的anti-TEM1-Sap(20~200nmol/L)能有效地杀死肉瘤细胞。在TEM1阳性的肉瘤动物模型中,抗体浓度为100nmol/L的anti-TEM1-Sap处理的小鼠与Sap单独处理的小鼠相比,其抑制肿瘤生长的作用显著增强(P<0.01)。结论 TEM1蛋白在多种肉瘤细胞系中高表达,靶向TEM1的细胞毒性物质比单独使用细胞毒性物质更能促进肉瘤细胞的凋亡,为肉瘤的诊断及精准治疗提供了新思路。

Abstract:

Objective To investigate the inhibitory effect of tumor endothelial marker 1 (TEM1) antibody-conjungated Sap on human sarcoma cells in vitro and in vivo. Methods Cytotoxic agent Sap was chemically conjugated to TEM1-antibody (anti-TEM1-Sap). The expression of TEM1 was detected by qPCR and flow cytomety in uterine sarcoma MES-SA, SKUT-1 cells, osteosarcoma HOS, SJSA-1, A673, U2OS, SAOS-2 cells, human fibrosacoma HT1080 cells and uterine carcinoma AN3CA, RL95-2 and KLE cells. Human uterine sarcoma MES-SA cells were subcutaneous inoculated in nude mice. The tumor bearing mice were injected with anti-TEM1-Sap, and its inhibitory effect was analyzed. ResultsTEM was highly expressed in SJSA-1, A673, MES-SA and HOS cells. Anti-TEM1-Sap at dose of 100nmol/L significantly inhibited the tumor growth in uterine sarcoma-bearing nude mice. Conclusion TEM1-targeted immunotoxin can effectively inhibit TEM1-positive sarcoma in vitro and in vivo, which may have the potential for clinical application.