【Objective】 O6 methylguanine DNA methyltranferase (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.