To improve the selection of patients who would benefit from this cytotoxic regimen and avoid unnecessary toxicity due to treatment failure, predictive biomarkers need to be identified.7 Potential predictive biomarkers, such as MGMT expression, tumor grade and serum alanine aminotransferase (ALT) activation, have been investigated; however, the results have been controversial. The gene discussed is GPT; the disease is neoplasm.