When compared to the control P1 glioma cells treated with lentiviral scramble control shRNA plus the CRISPR/Cas9 control construct (“shC+Cas9-C”), the expression of ORC6 mRNA (Fig. 4A) and protein (Fig. 4B) was significantly reduced in shORC6-s1/s2 P1 glioma cells and koORC6 P1 glioma cells. This evidence concerns the gene ORC6 and central nervous system cancer.