XRCC4 and central nervous system cancer: The authors also suggested that exosomal SBF2-AS1 secreted by TMZ-resistant cells might spread TMZ resistance to nearby glioma cells and that SBF2-AS1 might downregulate miR-151a-3p in a ceRNA network manner, upregulate X-ray repair cross-complementing protein 4 (XRCC4) and promote the repair of TMZ-induced DNA damage [49].