GGH intronic variant rs3780130 is associated with methotrexate levels in children with brain tumors

Pediatric brain tumors (PBTs) are the leading type of solid tumors in children, profoundly affecting both survival rates and quality of life. Methotrexate (MTX) is an essential chemotherapy drug for treating these tumors; however, its efficacy and toxicity vary among patients due to genetic factors.

This study examined the impact of the intronic rs3780130 polymorphism in the gamma-glutamyl hydrolase (GGH) gene on MTX concentrations and related toxicities in patients with PBTs.

The GGH rs3780130 T > A polymorphism was genotyped using the Sequenom MassARRAY iPLEX platform in a cohort of 73 PBT patients.

We found that children with the AA genotype had significantly higher MTX concentrations compared to those with TT and TA genotypes (P < 0.05). Additionally, the AA genotype was significantly associated with a higher incidence of hepatotoxicity relative to the TT genotype (P < 0.05). It showed a significantly lower occurrence of gastrointestinal toxicities when compared to the TA genotype (P < 0.05). Bioinformatics analysis revealed that the rs3780130 polymorphism had a significant effect on GGH expression across various tissues, suggesting a potential mechanism by which this variant modulated MTX metabolism.

Our findings highlight the importance of GGH polymorphisms in personalizing MTX therapy for PBT patients and emphasize the necessity for further research to explore the clinical implications of GGH genotypes in larger cohorts, ultimately aiming for more precise therapeutic strategies.