小剂量维甲酸诱导对神经母细胞瘤耐药的影响

Effects of retinoic acid on chemotherapy resistance in neuroblastoma

目的探讨小剂量维甲酸诱导对神经母细胞瘤(NB)化疗耐药的影响。方法选择人NB细胞株SH SY5Y,用RT PCR方法检测小剂量全反式维甲酸(ATRA)作用下TrkB mRNA水平;通过四甲基偶氮蓝比色(MTT)法及流式细胞仪(FCM)检测ATRA诱导前后顺铂对人NB细胞株SH SY5Y的生长及凋亡的影响。结果SH SY5Y中未检测到TrkB mRNA表达,用1、10、100nM/LATRA诱导5d后可检测到TrkB mRNA表达,且随ATRA浓度增加TrkB mRNA水平逐渐升高。100nM/LATRA诱导7d,TrkB mRNA的相对比值与诱导5d比差异无显著性意义(P>0.05);MTT分析显示:BDNF+顺铂组(无TrkB表达)、ATRA+顺铂组(无BDNF刺激)细胞存活率同单用顺铂组比较无显著性差异(P>0.05);10nM/LATRA+BDNF+顺铂组NB细胞存活率明显高于单用顺铂组(P<0.01);FCM分析显示:ATRA+BDNF+顺铂组NB细胞凋亡率明显低于单用顺铂组(P<0.01)。结论存在BDNF的条件下,小剂量ATRA能阻断顺铂对SH SY5Y的细胞毒性作用,从而使SY5Y细胞对化疗耐药。

Objective To assess the effects of retinoic acid on the chemotherapy resistance in neuroblastoma (NB). Methods Using human neuroblastoma cell line, TrkB expressions before and after all-trans retinoic acid (ATRA) treatment of were examined by reverse-transcriptase-polymerase chain reaction (RT-PCR). Effect of ATRA on cell proliferation and apoptosis after cisplatin treatment on the human NB cell line were assessed with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry . Results TrkB-mRNA was not detectable in SH-SY5Y cell lines. After induction with 1、10、 100nM/L ATRA for five days , TrkB-mRNA was detected at a level which positively correlates with the concentrations of ATRA. No further increase of TrkB was found after administering 100nM/L ATRA for seven days. MTT analysis showed that there was no difference in cell survival rate between the BDNF+Cisplatin group and ATRA+Cisplatin group (P >(0.05)). The cell survival rate of 10nM/L ATRA+BDNF+cisplatin group was significantly higher than that of the cisplatin alone group. Flow cytometry analysis showed that the apoptosis rate of ATRA+BDNF+cisplatin group was significantly lower than that of the cisplatin alone group(P <(0.01)). Conclusions In the condition of existing BDNF,ATRA minimizes the cisplatin cytotoxicity on SH-SY5Y and renders the SY5Y cell line resistant to the chemotherapy