The levels of MGMT autoantibodies decreased on the 30th day after operation, reaching preoperative levels, similar to those when tumor recurrence developed.
This meta-analysis suggests that MGMT expression may be associated with PA tumor recurrence, but not be related to invasiveness or other clinicopathological indicators.
We also observed the expression of stemness-related genes in G1 recurrent tumors and the altered expression of DNA-repair genes (i.e., AURK, HOX, MGMT, and MSH6) in the G2 recurrent tumors, which might be responsible for the acquisition of drug resistance mechanism during tumor recurrence in a subtype-specific manner.
Promoter hypermethylation in the O(6)-methylguanine-deoxyribonucleic acid methyltransferase (MGMT) genes was detected and MGMT protein expression was negative in the recurrent tumor, so temozolomide (TMZ) salvage chemotherapy was given, and follow-up MR imaging showed tumor reduction.
The promoter methylation status of the DNA repair gene MGMT and the tumor suppressor genes CDKN2A and RASSF1 were evaluated by methylation-specific PCR in 88 primary oral and pharyngeal tumors and correlated with survival and tumor recurrence.