[重组转化生长因子α-绿脓杆菌外毒素40对人膀胱癌细胞增殖的抑制作用]

[Inhibitory effect of recombinant transforming growth factor alpha-pseudomonas exotoxin 40 on human bladder cancer cell proliferation].

作者信息

Yan Xiang, Ding Qiang, Zhang Yuan-fang, Xu Yong-hua

机构信息

Department of Urology, Huashan Hospital of Fudan University, Shanghai 200040, China.

出版信息

Zhonghua Wai Ke Za Zhi. 2004 Dec 7;42(23):1457-9.

PMID:15733465

Abstract

OBJECTIVE

To study inhibitory effect of recombinant transforming growth factor alpha-Pseudomonas exotoxin fusion protein (TP40) on proliferation of the human bladder cancer T24 cells.

METHODS

Expression of epidermal growth factor receptor (EGFR) in cultured T24 cells was analyzed with Western blot assay. Human bladder cancer T24 cells were exposed to TP40 at 5 - 1 000 microg/L. Methyl thiazolyl tetrazolium assay was applied to evaluate the cell proliferation by measuring the absorbance (A) at 570 nm with a microplate reader. Tritium labeled thymine deoxyriboside ([(3)H]-TdR) uptake was measured to observe DNA synthesis. Competition assays were performed by the EGF at 1 - 7 500 microg/L.

RESULTS

Expression of EGFR was high in human bladder cancer T24 cells. Cell growth was suppressed by 10%, 19%, 27%, 41%, 47%, 53% and 61% after 96 h treatment with TP40 at 5, 50, 100, 250, 500, 750 and 1 000 microg/L, respectively. [(3)H]-TdR incorporation was 80%, 69%, 48% and 51% after 24 h, 48 h, 72 h, 96 h treatment with TP40 at 750 microg/L, respectively. When the concentration was 1 - 7 500 microg/L, EGF could block the inhibitory effect of TP40 to some extent.

CONCLUSIONS

Human bladder cancer T24 cells express EGFR at a high level. TP40 could inhibit the growth of T24 cells effectively in a dose- and time-dependent manner. The cytotoxic effects of TP40 were specifically mediated by EGFR.

摘要

目的

研究重组转化生长因子α-绿脓杆菌外毒素融合蛋白（TP40）对人膀胱癌T24细胞增殖的抑制作用。

方法

采用蛋白质免疫印迹法分析培养的T24细胞中表皮生长因子受体（EGFR）的表达。将人膀胱癌T24细胞暴露于浓度为5 - 1000μg/L的TP40中。采用甲基噻唑基四氮唑法，通过酶标仪测量570nm处的吸光度（A）来评估细胞增殖。测量氚标记胸腺嘧啶脱氧核苷（[³H]-TdR）摄取量以观察DNA合成。用浓度为1 - 7500μg/L的表皮生长因子（EGF）进行竞争试验。

结果

人膀胱癌T24细胞中EGFR表达较高。用5、50、100、250、500、750和1000μg/L的TP40处理96小时后，细胞生长分别被抑制10%、19%、27%、41%、47%、53%和61%。用750μg/L的TP40处理24小时、48小时、72小时、96小时后，[³H]-TdR掺入率分别为80%、69%、48%和51%。当浓度为1 - 7500μg/L时，EGF可在一定程度上阻断TP40的抑制作用。