These results suggest that ABCG2 and XIAP proteins may be useful indicators of patient survival and that inhibition of ABCG2 may be a promising therapeutic strategy in GBMs.
To study the mechanisms of human glioblastoma cell resistance to methyl ester pyropheophorbide-a-mediated photodynamic therapy (MPPa-PDT) and the relationship between the cells and adenosine triphosphate-binding cassette superfamily G member 2 (ABCG2).
The mRNA levels of stemness genes such as Nanog, CD133, and ABCG2 were much higher in the SP cells, and so was E-cadherin, which was reported to correlate with the aggressiveness of glioblastoma multiforme.
We used genetically engineered spontaneous glioblastoma mouse models and allograft models that were orthotopically transplanted into wild-type (WT) and Abcb1/Abcg2-deficient (KO) recipients.
To study a correlation between promoter methylation and gene expression, we analyzed MGMT, ABCB1 and ABCG2 expression in 20 glioblastoma and 7 non-neoplastic brain samples.
In addition, GSAA predicted novel pathway associations, for example, differential genetic and expression characteristics in genes from the ABC transporter family in glioblastoma and from the HLA system in Crohn's disease.
Thus, we hypothesize that modulating ABCG2 expression by targeting miRNA-328 in glioblastoma cancer stem cells could represent a promising strategy for therapeutic manipulation to increase the efficacy of chemotherapeutic agents for glioblastoma, a highly lethal type of cancer.
These studies suggest a role for brain endothelial ABCG2 transporter in modulating drug delivery to the brain and in conferring drug resistance to glioblastomas.