CCND2 and central nervous system cancer: For example, SP1 binds to the MDK gene promoter and directly promotes MDK expression, showing the SP1‐MDK axis cooperated in glioma tumourigenesis.25 More and more lncRNAs have been identified to participate in the gliomagenesis with increasing evidence,26, 27 such as, lncRNA FOXD2‐AS1 is up‐regulated in glioma tissue/cells and CCND2 is also up‐regulated.