THBS1 and oligodendroglioma: Other genes hypermethylated in oligodendrogliomas include the tumor suppressors CDKN2A, CDKN2B and RB1, as well as DAPK1 (death-associated protein kinase 1), ESR1 (estrogen receptor 1), THBS (thrombospondin 1) and TIMP3 (tissue inhibitor of metalloproteinase 3) [81–83].