摘要
【目的】探讨干扰素是否能增加替莫唑胺(TMZ)对O6甲基鸟嘌呤DNA甲基转移酶(MGMT)阳性胶质瘤干细胞的抗肿瘤作用及其可能机制。【方法】采用"悬浮克隆球形成法"对常规培养条件下MGMT阴性表达的胶质瘤细胞株U251、SKMG-4进行诱导,获得MGMT阳性的胶质瘤干细胞U251G、SKMG-4G;应用CCK-8法检测干扰素-α和干扰素-β联合替莫唑胺对MGMT阳性胶质瘤干细胞的杀伤效应;分别应用逆转录PCR(RT-PCR)、Western-blot检测干扰素-α/β作用后,MGMT阳性胶质瘤干细胞MGMT、NF-κB表达的变化。【结果】应用悬浮克隆球形成法,成功将U251、SKMG-4诱导为具有干细胞特征的胶质瘤干细胞U251G、SKMG-4G,Western-blot检测显示胶质瘤干细胞中MGMT蛋白表达明显增高。对MGMT阳性胶质瘤干细胞生长抑制实验显示,干扰素-α/β作用后提高了替莫唑胺的化疗敏感性,杀伤效应显著增强;RT-PCR、Western-blot检测结果表明,干扰素-α/β作用后,MGMT阳性胶质瘤干细胞NF-κB、MGMT在mRNA及蛋白水平表达均明显降低。【结论】对于MGMT阳性的胶质瘤干细胞,干扰素-α/β能够显著增加替莫唑胺的抗肿瘤效应,其机制可能是干扰素-α/β干预后,下调NF-KB的表达,从而降低了MGMT的转录表达,逆转替莫唑胺的化疗耐药。
[ Objective ] O^6 methylguanine DNA methyhranferase （MGMT） is one of the main mechanisms of chemoresistance for alkylating agents in malignant glioma. Recent studies showed that glioma stem cells （GSC） was the main cause for tumor recurrence and chemoresistance. This study aimed to explore the effects of interferon-α/β against MGMT-positive glioma stem cells, and to investigate whether Interferon-α/β can enhance the efficiency of temozolomide and the possible mechanism. [Methods] Glioma cell line U251 and SKMG-4, MGMT-negative in conventional culture, were induced through serum-free clone culture to get MGMT- positive GSC U251G and SKMG-4G. CCK-8 assay was used to test the growth inhibition effect of temozolomide with interferon-α/β against the MGMT-positive GSC. RT-PCR and Western blot analysis were applied to detect the MGMT and NF-κB expression in MGMT-positive GSC administered by interferon-α/β. [Results] GSC were successfully obtained from two parental glioma cell lines U251 and SKMG-4, and MGMT expression in GSC was significantly increased determined by Western blot analysis. The chemotherapy sensitivity of temozolomide was significantly enhanced by using interferon-α/β in vitro. The expression of NF-κB and MGMT in MGMT-positive GSC decreased significantly in both mRNA and protein levels after using interferon-α/β through RT-PCR and Western-blot tests. [ Conclusion ] As to MGMT-positive GSC, interferon-α/β can enhance the sensitivity of temozolomide, and down- regulate NF-κB expression, lower MGMT transcription expression and reverse the chemoresistance of temozolomide.
出处
《中山大学学报（医学科学版）》
CAS
CSCD
北大核心
2012年第3期368-372,共5页
Journal of Sun Yat-Sen University:Medical Sciences
基金
国家自然科学基金(30772551)
广东省自然科学基金(2011B031800178)
