On the contrary, Jantas et al. [8] reported that GRM8 overexpression significantly inhibited cell proliferation and enhanced cell chemosensitivity in human neuroblastoma (SH-SY5Y) and glioma (LN229, U87-MG, and LN18) cells, suggesting that GRM8 functions as a tumor-suppressive gene in human neuroblastoma and glioma. Here, GRM8 is linked to central nervous system cancer.