To explore the interaction between long non-coding RNA growth arrest-specific 5 (GAS5) and miR-135b-5p/adenomatous polyposis coli (APC) axis, and to elucidate its biological function in the proliferation, metastasis and invasion of glioma.

The relationship of GAS5 expression level with survival rate of glioma patients was analyzed based on CGGA database. qRT-PCR was used to detect the expression level of GAS5 in glioma tissues and cell lines. Human glioma T98 and A172 cell lines were subjected for overexpression and knockdown of GAS5, miR-135b-5p and APC by transfection. Western blotting and qRT-PCR were applied to measure the expression of related genes in glioma tissues or cell lines. CCK-8, Transwell and wound healing assays was conducted to determine the effect of GAS5 on the viability and motility of glioma cells. Moreover, dual luciferase reporter analysis were utilized to elucidate the regulatory mechanisms of GAS5 and miR-135b-5p/APC.

‍Analysis on CGGA database showed that the survival rate of glioma patients with low GAS5 expression was significantly decreased (P<0.001). Western blotting and qRT-PCR indicated that GAS5 was down-regulated in the glioma cell lines and tissues than human normal astrocytes and para-cancer tissues (P<0.01). The results of CCK-8, Transwell and wound healing assays revealed that overexpression of GAS5 significantly inhibited the viability, invasion and migration abilities in T98 cells when compared with the cells of the vector group (P<0.01). Dual luciferase reporter analysis displayed that there were binding sites between GAS5 and miR-135b-5p, and the expression of the two was negatively correlated (P=0.019). Further studies suggested that the effect of GAS5 on biological function in glioma cells was through targetingmiR-135b-5p, and overexpression of APC reversed the promoting effect of miR-135b-5p on glioma cells (P<0.01). Western blotting displayed that enhancing miR-135b-5p expression inhibited the expression of APC (P<0.001), and GAS5 upregulated the expression of APC by targeting miR-135b-5p (P<0.01).

GAS5 inhibits the progression of glioma via miR-135b-5p/APC axis, which revealing the molecular regulatory mechanism of GAS5/miR-135b-5p/APC.