Heterogeneity of Human Gliomas: Glutathione-S-Transferase Expression Profile During Disease Progression and Under Systemic Therapy

Background/Aim: The glutathione S-transferase pi gene (GSTP1) is a polymorphic gene encoding functionally different Gstp1 isoenzyme proteins. These seem to contribute to xenobiotic metabolism and might also play a role in susceptibility to cancer. The aim of this study was to elucidate the potential role of GSTP1 as a biomarker for disease progression and predictor of chemotherapeutic effect in glioma. Materials and Methods: Using quantitative real time PCR and western blotting analysis, a total of 61 astrocytic tumor samples from WHO grade II-IV were investigated. Results: There were no differences in GSTP1 mRNA expression between diffuse astrocytomas, anaplastic astrocytomas, or GBM. No difference was seen between secondary GBM before and after radio-/chemotherapy. Conclusion: The expression of GSTP was highly heterogeneous within the surgical specimens. No significant differences in gene and protein expression were detected between the different types of gliomas, suggesting that glioma chemoresistance is probably multifactorial and GSTP1-independent