Elucidation of adverse events of methotrexate based on genomic and proteomic analysis in childhood leukemia patients

甲氨蝶呤大剂量用于治疗儿童急性淋巴细胞性白血病和恶性淋巴瘤。然而，肝毒性和骨髓抑制往往限制了它的使用。我们试图确定与甲氨蝶呤的肝毒性和消除相关的遗传多态。采用聚合酶链式反应和直接测序法对26例乳腺癌患者谷胱甘肽S转移酶基因(GSTT1阳性/空、GSTM1阳性/空、GSTP1A313G)、还原型叶酸携带者1G80A(Rfc1 G80A)、亚甲基四氢叶酸还原酶C677T(MTHFR C677T)和乳腺癌耐药蛋白C421A(BCRPC421A)基因进行了检测。GSTM1阳性、Rfc1 AA(80)者肝毒性发生率高(P=0.035)，MTFRTT677基因携带者输注后48h血药浓度明显升高(P=0.028)。综上所述，GSTM1阳性/空和Rfc1 G80A基因多态性可作为肝毒性的预测因子，MTHFR C677T基因多态性与甲氨蝶呤的清除有关。此外，天冬酰胺酶所致急性胰腺炎是维持治疗中的一个关键问题。我们试图阐明与胰腺炎相关的基因多态性，但没有发现预测胰腺炎的基因多态性。这些结果可能对儿童急性淋巴细胞白血病和恶性淋巴瘤的治疗提供有用的信息。

Methotrexate is administered in high doses to treat childhood acute lymphoblastic leukemia and malignant lymphoma. Hepatotoxicity and bone marrow suppression often limit its use, however. We tried to determine the genetic polymorphisms associated with the hepatotoxicity and elimination of methotrexate. Genetic polymorphisms of glutathione S-transferase (GST) genes including GSTT1 positive/null, GSTM1 positive/null, and GSTP1 A313G, and genes for reduced folate carrier 1G80A (RFC1 G80A), methylenetetrahydrofolate reductase C677T (MTHFR C677T), and breast cancer resistant protein C421A (BCRP C421A) were determined for 26 patients by the polymerase chain reaction (PCR) method or by direct sequencing. A high frequency of hepatotoxicity (P = 0.035) was observed for patients with GSTM1 positive and RFC1 AA(80), and serum concentrations of methotrexate 48 h after the start of infusion were higher for patients with the TT(677) genotype of MTHFR (P = 0.028). In conclusion, GSTM1 positive/null and RFC1 G80A polymorphisms could be predictors for hepatotoxicity, and the MTHFR C677T polymorphism.is associated with elimination of methotrexate.In addition, asparaginase-induced acute pancreatitis is a critical problem in maintenance therapy. We tried to clarify the genetic polymorphisms associated with pancreatitis, but no polymorphism to predict pancreatitis was found.Theses results could be useful information in treatment for childhood acute lymphoblastic leukemia and malignant lymphoma.