COL18A1 and central nervous system cancer: In our study, we confirm that miR-9 can directly bind to the 3’-UTR of COL18A1, THBS2, PTCH1 and PHD3, promote the degradation of these mRNAs and initiate HIF-1α/VEGF signal transduction, thus markedly enhancing tumorigenesis and angiogenesis during the glioma progression.