Vinblastine and antihelmintic mebendazole potentiate temozolomide in resistant gliomas

Glioblastoma (GBM) is a very aggressive tumor that has not had substantial therapeutic improvement since the introduction of temozolomide (TMZ) in combination with radiotherapy. Combining TMZ with other chemotherapeutic agents is a strategy that could be further explored for GBM. To search for molecular predictors of TMZ resistance, the TCGA (The Cancer Genome Atlas) database was utilized to assess the impact of specific genes on TMZ response. Patients whose tumors expressed low levels of FGFR3 and AKT2 responded poorly to TMZ. Combination treatment of vinblastine (VBL) plus mebendazole (MBZ) with TMZ was more effective in reducing cell number in most cultures when compared to TMZ alone, especially in cells with low expression levels of FGFR3 and AKT2. Cell cycle distribution and nuclear morphometric analysis indicated that the triple combination of TMZ, VBL and MBZ (TVM) was able to induce polyploidy and senescence, in addition to increasing the Notch3 RNA level in patient-derived gliomas. Thus, this set of data suggests that the triple combination of TMZ, VBL and MBZ may be a considerable therapeutic alternative for the TMZ-tolerant gliomas that harbor low expression of FGFR3/AKT2.