[Relation between single Nucleotide Polymorphisms of CYP3A5 Gene and MDR1 Gene Loci and Risk of CML Cytogenetic Relapse].

Objective: To analyze the relation between the signle nucleotide polymorphisms (SNP) of CYP3A5 gene and MDR1 gene loci and the risk of cytogenetic relapse in chronic myeloid leukemia (CML).

Methods: The clinical data of 90 patients with CML treated with imatinib in our hospital were collected.The patients were divided into 2 groups: non-relapse and relapse according to relapse and non-relapse, then the relation between the SNP of CYP3A5 gene and MRD1 gene loci and the risk of cytogenetic relapse in CML patients.

Results: The grouping result showed that the patients with non cytogenetic relapse accounted for 41 cases those were enrolled in non-relapse group, and patient-with cytogenetic relapse accounted for 49 cases those were enrolled in relapse group. The follow-up time was 36 months. The detection showed that the incidence of cytogenetic relapse in the patients with CC genotype was significantly higher than that in the patients with TT+CT genotype of C3435T and C1236T at MDR1 gene loci (P<0.05).Compared with the patients with CT+CC genotype in C3435T locus of MDR1 gene, the rate of cytogenetic relapse in the patients with TT genotype decreased significantly (P<0.05). Compared with patients with CT+CC phemotype of C3435T in MDR1 gene locus, the non-relapse survival time of TT genotypes was significantly prolonged (P<0.05). Compared with non-relapse group, the incidence of neutropenia (29.27% vs 71.43%) and blood toxicity (39.02% vs 61.22%) in the relapse group increased significantly (P<0.05). The imatinib dose (OR=2 95, 95% CI:1.37~7.76) and the C3435T genotype in MDR1 genes (OR=0.09, 95% CI:0.05~0.72) were the factors affecting the cytogenetic relapse of the patients with CML (both P<0.05).

Conclusion: The therapeutic dose of imatinib and the C3435T and C1236T genotypes in MDR1 gene have a certain effect on the cytogenetic relapse of CML patients. C3435T genotypes in the.MDR1 gene showed a certain predictive value for evaluating the risk of cytogenetic relapse, which can be used as a clinical biomarker.