Besides, hsa_circ_0008344 (Zhou et al., 2018), hsa_circ_0029426 (Zhang G. et al., 2019), hsa_circ_0067934 (Xin et al., 2019), circ-SKA3 (Zhou M. et al., 2021), circ-PARP4 (Zhou J. et al., 2021), circ-FLN1 (Sun et al., 2021) and circ-NF1(Liu L. et al., 2021) were also shown to significantly promote the proliferative capacity and tumor growth of GBM cells, but the specific molecular mechanisms remain to be further explored. This evidence concerns the gene PARP4 and glioblastoma.