Influence of methylenetetrahydrofolate reductase gene polymorphisms on the outcome of pediatric patients with non-Hodgkin lymphoma treated with high-dose methotrexate

Involvement of the ABCB1 C3435T Variant but Not the MTHFR C677T or MTHFR A1298C Variant in High-Dose Methotrexate-Induced Toxicity in Pediatric Acute Lymphoblastic Leukemia Patients in China

Purpose

It remains unclear whether the MTHFR C677T, MTHFR A1298C and ABCB1 C3435T genetic variants are associated with methotrexate (MTX) elimination delay and high-dose MTX (HD-MTX) toxicities in the treatment of pediatric acute lymphoblastic leukemia (ALL). The aim of our study was to analyze the potential predictive role of MTHFR C677T, MTHFR A1298C and ABCB1 C3435T in toxicities and the relationship between these variants and MTX elimination delay during HD-MTX therapy in pediatric ALL patients.

Patients and Methods

We conducted a retrospective study on ALL patients receiving HD-MTX treatment with available MTHFR C677T, MTHFR A1298C and ABCB1 C3435T genotype and 44-h plasma MTX levels. Logistic regression analyses and chi-square tests were used to assess the relationship between the variants and HD-MTX toxicities and MTX elimination delay.

Results

Genotype frequencies were in Hardy-Weinberg equilibrium. MTX elimination delay did not significantly differ between MTHFR C677T and MTHFR A1298C or ABCB1 C3435T. Leukopenia (P=0.028), neutropenia (P=0.034) and oral mucositis (P=0.023) were 6.444-fold, 4.978-fold and 9.643-fold increased, respectively, in ABCB1 C3435T homozygous genotype (TT) patients compared to wild-type (CC) patients. No significant association was found between the toxicities investigated and MTHFR C677T or MTHFR A1298C.

Conclusion

This study showed that the ABCB1 C3435T homozygous allele genotype (TT) is associated with increased MTX-related toxicities (leukopenia, neutropenia and oral mucositis). These results may help to distinguish pediatric ALL patients with a relatively high risk of MTX-related toxicities before HD-MTX infusion and optimize MTX treatment.

Influence of MTHFR C677T and A1298C polymorphisms on the survival of pediatric patients with non-Hodgkin lymphoma

This study evaluated the influence of MTHFR C677T/A1298C polymorphisms on the survival of pediatric NHL. We enrolled 374 patients including 283 males and 91 females between 2014 and 2020. The median age was 9 years. The tumor types included Burkitt lymphoma (n = 180), lymphoblastic lymphoma (n = 95), anaplastic large cell lymphoma (n = 64), and diffuse large B cell lymphoma (n = 35). A subgroup of 158 patients were genotyped concerning C677T/A1298C polymorphisms. Neither C677T nor A1298C polymorphism was a significant factor in multivariate analysis. However, Kaplan-Meier analysis revealed that patients carrying 677 T allele had a significantly higher 5-year EFS rate in the whole group (n = 158), and higher 5-year EFS/OS rates in the subgroup of BL/DLBCL than those with wild type. In conclusion, the C677T polymorphism could be used for survival prediction and potential risk stratification for further treatment protocols for Chinese pediatric NHL, especially for BL/DLBCL.

Influence of Methylenetetrahydrofolate Reductase C677T and A1298C Polymorphism on High-Dose Methotrexate-Related Toxicities in Pediatric Non-Hodgkin Lymphoma Patients

Purpose

This retrospective study aimed to investigate the relationships between the methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C and high-dose methotrexate (HD-MTX)-related toxicities in pediatric non-Hodgkin lymphoma (NHL) patients.

Patients and Methods

We reviewed the medical records of 93 NHL patients aged under 18 years who received HD-MTX therapy at the dose of 5 g/m² with 24-h infusion at Sun Yat-sen University Cancer Center between 2014 and 2019.

Results

There were 61 males and 32 females, with a median age of 8.8 years (0.9–15.8 years). The tumor types included lymphoblastic lymphoma (n = 38), Burkitt’s lymphoma (n = 31), anaplastic large cell lymphoma (n = 18), diffuse large B-cell lymphoma (n = 6). Overall, 355 courses of HD-MTX therapy were prescribed. All patients were rescued with calcium folinate 12 h after the end of MTX infusion. We found that plasma MTX levels > 0.2 μmol/L at 48 h post-infusion increased the risk of developing oral mucositis (2.4% VS. 9.5%, P = 0.018). Also, patients carrying the C677T and T677T genotypes had tendencies to be more susceptible to oral mucositis (P = 0.034). Patients harboring mutant 677T allele were more likely to develop leucopenia (38.5 vs. 50.3%, P = 0.025) and thrombocytopenia (22.0 vs. 32.4%, P = 0.028). For polymorphism A1298C, the mutant genotype played a protective role in vomiting (11.1 vs. 4.3%, P = 0.018) but increased the risk of anemia (23.8 vs. 41.7%, P < 0.001) and leucopenia (38.1 vs. 50.3%, P = 0.021).

Conclusion

Childhood NHL patients harboring C677T genotype were more vulnerable to oral mucositis, leucopenia, and thrombocytopenia, while those with A1298C genotype were at a decreased risk of vomiting and more likely to develop anemia and leucopenia.

Systematic review of pharmacogenomics and adverse drug reactions in paediatric oncology patients

Many paediatric patients with cancer experience significant chemotherapy side effects. Predisposition to drug reactions is governed by single nucleotide polymorphisms (SNPs). We performed a systematic review of the literature from 2006 through 2016. Outcomes of interest included patient characteristics, cancer type drug of interest, genes investigated, toxicity identified and genetic polymorphisms implicated. The primary toxicities studied were neurotoxicity cardiotoxicity, osteonecrosis, and thromboembolism and hypersensitivity reactions. The retrieved studies were grouped according to toxicity reported and SNP associations. This review highlights the discoveries to date in pharmacogenomics and paediatric oncology along with highlighting some of the important limitations in the area.

Pharmacogenomics in Pediatric Oncology: Review of Gene-Drug Associations for Clinical Use

During the 3rd congress of the European Society of Pharmacogenomics and Personalised Therapy (ESPT) in Budapest in 2015, a preliminary meeting was held aimed at establishing a pediatric individualized treatment in oncology and hematology committees. The main purpose was to facilitate the transfer and harmonization of pharmacogenetic testing from research into clinics, to bring together basic and translational research and to educate health professionals throughout Europe. The objective of this review was to provide the attendees of the meeting as well as the larger scientific community an insight into the compiled evidence regarding current pharmacogenomics knowledge in pediatric oncology. This preliminary evaluation will help steer the committee’s work and should give the reader an idea at which stage researchers and clinicians are, in terms of personalizing medicine for children with cancer. From the evidence presented here, future recommendations to achieve this goal will also be suggested.

Effect of folate status and methylenetetrahydrofolate reductase genotypes on the complications and outcome of high dose methotrexate chemotherapy in north Indian children with acute lymphoblastic leukemia

Purpose:

The genes of the folate metabolic pathway have been associated with toxicities during high dose methotrexate therapy for childhood ALL, however, the importance of intrinsic folate status in this regard is unclear.

Methods:

In the present study the effect of precourse folate levels and MTHFR genotypes on the complications during high dose methotrexate chemotherapy in children with ALL were examined.

Results:

Twenty-one children were studied. Folate deficiency was associated with higher incidence of neutropenia (P = 0.03) and longer duration of chemotherapy interruption (P = 0.009). Children with MTHFR1298 mutations needed more red cell transfusion (P = 0.03). All 3 deaths encountered were seen in folate deficient children.

Conclusions:

Folate deficiency was associated with higher complications during high dose methotrexate therapy, the implications of which are important especially in resource poor settings with high prevalence of folate deficiency.

Association of MTHFR C677T and A1298C polymorphisms with non-Hodgkin lymphoma susceptibility: evidence from a meta-analysis

Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism and DNA synthesis. A number of studies have examined the association of MTHFR C677T and A1298C polymorphisms with non-Hodgkin lymphoma (NHL) susceptibility; however, the conclusions were contradictory. We searched available publications assessing the polymorphisms of MTHFR and NHL susceptibility from MEDLINE, EMBASE and CBM. Genotype-based mRNA expression analysis was performed using data from 270 individuals with three different ethnicities. Ultimately, a total of 7448 cases and 11146 controls from 25 studies were included for the C677T polymorphism, 6173 cases and 9725 controls from 19 studies for the A1298C polymorphism. Pooled results indicated that neither C677T nor A1298C polymorphism was associated with NHL susceptibility. However, C677T polymorphism showed a statistically significantly increased risk for Caucasians, but a decreased risk for Asians in the subgroup analysis by ethnicity. The same variants may confer increased susceptibility to develop follicular lymphoma (FL). Moreover, A1298C polymorphism was associated with increased NHL risk for Asians. This meta-analysis indicated that C677T polymorphism was associated with altered NHL susceptibility for Caucasians, Asians and FL. Increased NHL risk was also shown for A1298C among Asians. These findings warrant validation in large and well-designed prospective studies.