EGFR and glioblastoma: Hypermethylation patterns have also been observed at the BCL2L11 promoter, the gene responsible for producing the pro-apoptotic protein BIM.306 Interestingly, EGFR inhibitor-resistant glioblastoma has decreased BIM expression in vitro and in vivo.307 Thus, DNMTs play a critical role in the aberrant methylation patterns that contribute to downregulation of tumour suppressor genes.