免疫细胞化学技术检测P－糖蛋白在人膀胱癌MDR细胞亚株中的表达

为探讨肿瘤细胞耐药性，以人膀胱癌细胞株ＢＩＵ－８７为亲本，以递增阿霉素剂量的方法，历时８个月，成功地诱导建立了一株耐药细胞亚株ＢＩＵ－８７／ＡＤＭ。通过生物学鉴定发现此细胞对阿霉素的相对时受度较亲本细胞提高了６．３倍，对阿霉素类似物柔红霉素、表阿霉素及天然生物碱类抗癌药长春新碱、鬼臼乙叉甙有明显的交叉耐药性，对顺铂、丝裂霉素则无交叉耐药性。为进一步阐明其耐药机理，应用链霉亲和素－生物素免疫细胞化学技术对其耐药性进行研究发现，约７５％的ＢＩＵ－８７／ＡＤＭ细胞Ｐ－ｇｐ过表达，而亲本细胞均为阴性。由此结果表明，ＢＩＵ－８７／ＡＤＭ耐药性的产生主要是由于Ｐ－ｇｐ膜泵功能增强介导产生细胞内药物外溢增多所致，是其产生耐药性的主要原因，ＢＩＵ－８７／ＡＤＭ的建立为进一步针对Ｐ－ｇｐ药泵功能逆转其抗药性的研究奠定了实验基础。

Detection of P-glycoprotein expression with immunocytochemistry in adriamycin-resistant human bladder cancer cell line

A human bladder tumor cell line resistant to adriamycin,BIU-87/ADM,has been established in vitro by the stepwise exposure of BIU-87 human bl adder cancer cell to increasing concentrations of the drug over a period of 8 months.BIU-87/ADM cell showed 6.3-fold higher resistance to adriamycin than BIU-87 parent cell.BIU-87/ADM cell line was shown to significantly cross-resistant to adriamycin derivatives(epirubicin,daunoubicin),vincristine and etoposide, but not to cisplatin and mitomycin C. Anti-p-glycoprotein monoclonal antibody JSB-1 and labelled streptaoavidin biotin(LSAB )immunocytochemical staining technique were used to study the relation between p-gp expression and MDR in BIU-87/ADM cell line.Unlike BIU-87 parent cell, about 75%of the BIU-87/ADM cell showed a positive reaction. The result indicated that there was a close association between the p-gp expression and the resistance to chemotherapeutic drug in BIU 87/ADM cell line. BIU-87/ADM may be a useful model for the development of new chemotherapeutic strategies in covercoming drug resistance in the treatment of bladder cancer.