OCT4 is up-regulated by DNA hypomethylation of promoter in recurrent gliomas
Abstract:
OCT4, a marker of embryonic stem cells, is also a key transcription factor that plays a regulatory role in the self-renewal, proliferation and differentiation of stem cells. Previous studies showed that DNA methylation is involved in the regulation of OCT4 expression during the development and differentiation of embryonic stem cells. However, DNA methylation in the promoter region of OCT4 has not yet been discussed in human recurrent glioma. In this study, we assessed the specimens from 24 cases of recurrent glioma for OCT4 expression and methylation status, and commenced analyzing the correlation between the two by treating glioma cells with a demethylating agent in vitro. The results demonstrated that for the same cases, the expression of OCT4 in specimens of recurrent glioma was significant higher than that in primary glioma (P DNA methylation levels in recurrent glioma decreased obviously compared with that in primary glioma (t=9.800, P=0.008). In vitro study indicated, following demethylation treatment, glioma cells had an increased OCT4 expression. These results suggest that DNA hypomethylation may be a key mechanism underlying the up-regulation of OCT4 in the recurrence of glioma, which facilitates the understanding of the role of stem cells and the exploration of novel strategies for the treatment of recurrent glioma.