The Prognostic Significance of TET2 Single Nucleotide Polymorphism in Egyptian Chronic Myeloid Leukemia

BACKGROUND: Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm where pathogenesis is based on the oncoprotein termed BCR-ABL1.1 TET2 initiates DNA demethylation and is frequently mutated in hematological malignancies, including CML. The relation between TET2 acquisition and CML transformation and/or imatinib resistance is needed to be investigated.2 AIM: To evaluate Ten Eleven Translocation 2 gene (TET2) single nucleotide polymorphism (SNP) (rs2454206, rs34402524, rs61744960) in chronic myeloid leukemia (CML) in relation to the disease prognostic criteria. MATERIALS & METHOD: The study included 84 subjects; 54 CML in chronic phase and 30 healthy subjects as control group matched for age and sex. Routine investigations, including CBC, bone marrow aspiration, biochemical investigations, and molecular study, were performed in CML patients to identify the disease stage. DNA extraction and SNP assay for TET2 gene polymorphism were done using (Thermo-Fisher predesigned SNP, USA) PCR prism 7500. RESULTS: The mean age was 45.98±15.7 yrs in CML patients and 39.3±6.587 yrs in the control group (p>0.05). TET2 SNP rs 34402524 was either heterozygous or homozygous in CML (48%, 46.2% respectively) but was mainly homozygous among control (80%) group (p=0.012). TET2 SNP rs 2454206 wild type within CML was detected in 65.4% of patients and in controls was 63.3% (p=0.046). TET2 SNP rs 61744960 showed a homozygous pattern among all groups (CML and control) (p=0.528). TET2 SNP in CML cases did not alter the prognostic criteria as no statistical significance was noted (p>0.05) yet, it was significantly related to spleen size in rs 34402524 where the homozygous group had larger spleen size and higher BCR-ABL1 levels six months after starting TKIs (p<0.05). CONCLUSIONS/RECOMMENDATION: TET2 SNP is common among Egyptian chronic myeloid leukemia. TET2 SNP rs 3442524 was associated with larger spleen size and higher BCR-ABL1 levels after six months of starting TKIs suggesting disease progression.