Similarly, we found that the expression of HOXC6, MMP9 and SHOX2 was higher in recurrent glioma tissues compared with primary glioma tissues and the expression of MYOD1 was decreased (Figures 6A,B), while there were no significant changes in WT1 and HOXA2 (Supplementary Figure S1). The gene discussed is MMP9; the disease is central nervous system cancer.