MAPK8 and neoplasm: To explore this possibility, we treated three glioma cell lines, SF8628 derived from an H3.3K27M tumor, and SF9402 and SF9427 derived from tumors with wild-type H3.3, with the JNK inhibitor SP600125, using assays that were previously described to test differences between the same K27M-negative and -positive glioma cell lines52.