Our data obtained in GBM biopsies and U87MG GBM cell line showed that circSMARCA5: (i) is significantly downregulated in GBM biopsies, as compared to normal brain parenchyma; (ii) acts as a decoy for the oncogenic Serine and Arginine Rich Splicing Factor 1 (SRSF1); (iii) shows a negative correlation between its expression and the number of blood vascular microvessel density; (iv) acts as a regulator of the SRSF1-mediated splicing activity; and (v) shows a positive correlation between its expression and both overall patient survival and progression free survival [8,18]. Here, SRSF1 is linked to glioblastoma.