p53上调凋亡调控因子增强胶质瘤干细胞对替莫唑胺化疗敏感性的研究

 目的　探讨不同CD133免疫原型的胶质瘤细胞对替莫唑胺（TMZ）耐药性的差异以及p53上调凋亡调控因子（PUMA）改变胶质瘤细胞对TMZ敏感性的影响。方法　利用免疫磁珠细胞分选法筛选出CD+133和CD-133的胶质瘤细胞U87MG，分别传代培养，转染Ad-PUMA，并用TMZ干预。四甲基偶氮唑蓝比色法（MTT法）检测细胞增殖情况及对TMZ的半数抑制浓度（IC50），流式细胞术观察外源性PUMA、TMZ干预前后CD+133和CD-133细胞的凋亡情况。结果　CD+133免疫磁珠分选出胶质瘤干细胞，CD+133胶质瘤细胞IC50较CD-133胶质瘤细胞高[（200±10）μmol／L比（80±11）μmol／L]，转染Ad-PUMA后，两组细胞IC50均降低[（100±8）μmol／L比 （20±7）μmol／L]，两组转染前后IC50差异均有统计学意义（P < 0.05）。TMZ联合PUMA组CD+133细胞凋亡率为68.05 %，对照组、TMZ组及PUMA组分别为6.05 %、32.91 %和40.61 %，联合组与其他组比较差异均有统计学意义（均P＜0.05）。结论　PUMA联合TMZ可以促进耐药的胶质瘤干细胞凋亡，从而增强胶质瘤对化疗的敏感性。

PUMA enhanced chemotherapeutic sensitivity of human glioma stem cells against temozolomide

Objective To explore differences of drug resistance of temozolomide（TMZ） on different CD133 immune prototype of glioma cells and study on the changes of their sensitivity to TMZ through increased PUMA. Methods CD,;3-U87MG cells sorted by CD133 magnetic beads were cultured in serum-free stem cell medium respectively. The cells were infected with recombinant adenovirus, Ad-PUMA, diluted in cell culture medium with or without TMZ intervention. The inhibitory rate of cell proliferation was detected by MTr assay and 50 % inhibition concentration of TMZ was calculated. Apoptosis rates of CD133-U87MG cells were assessed by flow cytometry （FCM） before and after intervention of exogenous PUMA and TMZ. Results The TMZ IC50 values of CD133glioma cells were higher than that of CD133 glioma cells. There were significant differences in apoptosis rate between CD133 glioma cell and CD133 glioma cell （all P〈0.05）. Conclusion Ad- PUMA joint TMZ can promote glioma stem cells apoptosis, thus improve the sensitivity to chemotherapy of glioma.