Abstract: Objective To explore the function and molecular mechanism of HOXA transcript antisense RNA (myeloid-specific 1, HOTAIRM1) in glioma stem cells. Methods Real-time PCR detected the expression profile of HOTAIRM1 in glioma stem cells; Tumor spheroid formation assay and limiting dilution assay were used to detect the ability of self-renewal of tumor stem cells after HOTAIRM1 overexpression or knockdown; Real time PCR and Western blot were used to detect the expression of stemness markers; Dual-luciferase reporter gene assay was used to detect the effect of HOTAIRM1 on the activity of OCT4 promoter; All-trans retinoic acid (ATRA) was used to treat NB4 acute promyelocytic leukemia cells and glioma stem cells GSC2. Results Compared with the control group, the self-renewal ability of glioma stem cells overexpressing HOTAIRM1 was significantly enhanced (P<0.05); Western blot showed up-regulation of the stemness markers(P<0.05). The results of knocking down HOTAIRM1 were opposite. Overexpression of HOTAIRM1 promoted the transcriptional activity of the OCT4 promoter. The expression of HOTAIRM1 was down-regulated after ATRA treatment of GSC2. Conclusions HOTAIRM1 maintains self-renewal of glioma stem cells by modulating OCT4 expression.

Key words: Glioma stem cells, HOTAIRM1, OCT4, Self-renewal