冬凌草甲素对卵巢癌细胞紫杉醇耐药性的拮抗作用及其机制研究

目的探讨冬凌草甲素体内外对卵巢癌细胞紫杉醇耐药性的拮抗作用及其机制。方法通过大剂量冲击法,诱导制备耐紫杉醇的人卵巢癌HO-8910PM细胞株(HO-8910PM/PIX),用不同浓度冬凌草甲素处理HO-8910PM/PIX细胞;或在冬凌草甲素作用HO-8910PM/PIX细胞前以NF-κB激活剂TPA进行预处理。给药后,细胞经DAPI染色,荧光显微镜下观察细胞形态变化;CCK-8法检测细胞增殖;流式细胞仪检测细胞凋亡情况;Western blotting检测卵巢癌细胞中NF-κB蛋白的表达。建立裸鼠卵巢癌皮下移植瘤模型。接种后8周,观察冬凌草甲素对裸鼠皮下移植瘤生长的影响;免疫组织化学法检测肿瘤组织中NF-κB的阳性表达。结果与对照组相比,冬凌草甲素呈浓度相关性抑制卵巢癌HO-8910PM/PIX细胞增殖,显著诱导细胞凋亡,而TPA可显著削弱冬凌草甲素诱导细胞凋亡的作用。与HO-8910PM细胞相比,NF-κB在HO-8910PM/PIX细胞中表达显著上调,冬凌草甲素可抑制HO-8910PM/PIX细胞中NF-κB的表达。冬凌草甲素可显著抑制裸鼠卵巢癌皮下移植瘤生长,明显减弱移植瘤组织中NF-κB的阳性表达。结论冬凌草甲素体内外对卵巢癌细胞紫杉醇耐药性具有拮抗作用,该作用可能通过抑制NF-κB的表达而实现。

Antagonistic effect of oridonin on paclitaxel-resistance of ovarian cancer cells and its mechanism

Objective To investigate the antagonistic effect of oridonin on paclitaxel-resistance of human ovarian cancinoma cells and its mechanism.Methods Paclitaxel-resistant human ovarian cancer cell line(HO-8910PM/PIX) was established with HO-8910PM cells.HO-8910PM/PIX cells were treated with different concentrations of oridonin,or pretreated with NF-κB activator TPA,then followed by the treatment of oridonin.HO-8910PM/PIX cells morphological changes were observed under the fluorescence microscopy after DAPI staining,the cellular proliferation was detected by CCK-8 assay.The flow cytometry was used to determine the apoptosis.Western blotting was used to detect the protein expression of NF-κB in ovarian cancer cells.HO-8910PM/PIX cells were sc injected into nude mice to establish ovarian xenograft tumor model.Eight weeks after implantation,the inhibitory effect on growth of xenograft tumor in nude mice was observed.Immunohistochemistry was used to detect the positive expression of NF-κB in the tumor tissues.Results The proliferation of HO-8910PM/PIX cells was significantly inhibited by oridonin with a concentration correlation.Apoptotic rate induced by oridonin was markedly higher than that in the control group.However,pretreated with TPA,the apoptosis induced by oridonin was significantly attenuated.Compared to HO-8910PM cells,NF-κB protein expression in HO-8910PM/PIX cells was obversly up-regulated,which could be inhibited by oridonin.Oridonin could significantly inhibit the growth of xenograft tumor in nude mice and weaken the positive expression of NF-κB in xenograft tumor tissues.Conclusion Oridonin has antagonistic effect on paclitaxel-resistance of human ovarian cancer cells both in vivo and in vitro,which may be related to the down-regulation of NF-κB expression.