Figure 5.

PNKP represents a therapeutic target in pediatric pHGG. (A) Proliferation assays in patient-derived pHGG cell lines harboring wild-type or mutant H3.3 and transfected with siRNAs against Luciferase (siLUC, control) or PNKP (siPNKP_1 and siPNKP_2). Mean ± SEM from n independent experiments. The western blots show siRNA efficiencies (Tubulin or total protein stain, loading control). (B) Proliferation assays in U2OS H3.3 G34R transfected with an siRNA against PNKP 3′UTR (siLUC, control) and expressing the indicated GFP-tagged constructs. Mean ± SEM from n independent experiments. The western blots show PNKP knock-down efficiency and the expression levels of each construct (Tubulin, loading control). (C) Current model depicting PNKP-mediated misrepair of S phase DNA damage in H3.3 K27M and G34R mutant cells (left) and the consequences of PNKP targeting in these cells (right). Statistical significance is calculated by a polynomial quadratic model (A, B). *P< 0.05; **P< 0.01; ***P< 0.001; ns: P> 0.05.