Implication of lncRNA ZBED3-AS1 downregulation in acquired resistance to Temozolomide and glycolysis in glioblastoma

Temozolomide (TMZ) is the recommended drug for glioblastoma (GBM) treatment, but its clinical effect is restricted due to drug resistance. This research studies the effects of long non-coding RNA (lncRNA) ZBED3-AS1 and its related molecules on acquired TMZ resistance in glioblastoma (GBM). ZBED3-AS1 was identified to be downregulated in TMZ-resistant GBM cells by analyzing GSE113510 and GSE100736 datasets. ZBED3-AS1 downregulation was detected in TMZ-resistant GBM tissues and cell lines (U251/TMZ and U87/TMZ). ZBED3-AS1 knockdown promoted, whereas its overexpression suppressed TMZ resistance, viability and mobility, and glycolytic activity of TMZ-resistant cells. ZBED3-AS1 bound to Spi-1 proto-oncogene (SPI1) but did not affect its expression. Instead, it blocked SPI1-mediated transcriptional activation of thrombomodulin (THBD). SPI1 and THBD increased TMZ resistance and glycolysis in TMZ-resistant cells. Either ZBED3-AS1 overexpression or SPI1 knockdown in U87/TMZ cells blocked the growth of orthotopic and subcutaneous xenograft tumors in nude mice. In conclusion, this study demonstrates that ZBED3-AS1 downregulation and THBD activation is linked to increased TMZ resistance and glycolysis in GBM cells.