We hypothesized that CCDKN2A/B rs1063192 and rs4977756 and also the long noncoding RNA (lncRNA) CDKN2BAS rs2157719 glioma susceptibility polymorphisms identified by genome-wide association studies may contribute to medulloblastoma predisposition.
In order to test the candidacy of p16beta as a glioma suppressor, we replaced p16(INK4a), p15(INK4b) and p16beta wild-type as well as a series of seven glioma-derived p16beta alleles (R87H, A112V, R120H, A121V, G125R, A128A and A128V), into glioma cell lines that had either CDKN2A-/RB+ (U-87MG and U-251MG) or CDKN2A+/RB- (LN-319) endogenous backgrounds and demonstrated that p16beta can act as a functional glioma cell growth suppressor.