DPYD gene polymorphisms are associated with risk and chemotherapy prognosis in pediatric patients with acute lymphoblastic leukemia

We aimed to investigate the association between dihydropyrimidine dehydrogenase (DPYD) gene polymorphisms and the risk of pediatric acute lymphoblastic leukemia (ALL) and its prognosis after chemotherapy. A total of 147 pediatric ALL patients diagnosed by our hospital between January 2011 and December 2014 were included in the case group, and 102 healthy people who received a physical examination during the same time frame in our hospital were included in the control group. DNA sequencing was applied for site determination and genotyping of the DPYD 85T > C, 2194G > A, 1156G > T, and IVS14 + 1G > A polymorphisms. The genotype and allele frequencies of the two groups were compared. A significant difference was found in the comparison of the mutant gene and allele frequencies of the 85T > C polymorphism between the case and control groups (P < 0.05). The CT and CC genotypes in the 85T > C polymorphism were associated with the risk of the disease (OR = 1.592, 95 % CI = 1.010-2.509), suggesting that the recessive gene (85C) was more likely to lead to the occurrence of ALL compared with the dominant gene (85T) (P < 0.05). Patients carrying the C allele of the 85T > C polymorphism presented higher damage of their liver functions and higher infection rates compared with patients carrying the non-C allele (P < 0.05). A higher proportion of liver function damage and a higher infection rate were found in patients with the GA genotype in the IVS14 + 1G > A polymorphism compared with the GG genotype (P < 0.05). The complete remission (CR) rate in patients with the GG genotype in the IVS14 + 1G > A polymorphism was higher than in patients with the GA genotype (P = 0.020). After 5-fluorouracil/calcium folinate (5-FU/CF)-based chemotherapy, the event-free survival (EFS) rate of patients with the TT genotype was higher than patients with the CT and CC genotypes (P < 0.05). Our results revealed that the C allele of the 85T > C polymorphism might be associated with susceptibility to pediatric ALL. Patients carrying the C allele may have an increased risk of ALL. Thus, the 85T > C polymorphism may be a predictor of CR for pediatric ALL patients.