Expression of telomeric repeat binding factor 2 (TERF2) in childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most frequent cancer among children. Regardless of the advances in disease treatments, approximately 10-20 % of childhood ALL (cALL) have an incidence of relapse. Therefore, identification of additional prognostic variables is essential to provide specific therapeutic intervention for each patient. TERF2 is one of the main components of the shelterin complex (telosome) that plays a crucial role in the protective activity of telomeres. This research aims to investigate the expression level of TERF2 and its potential as a prognostic marker in cALL patients. 88 bone marrow samples and 6 peripheral blood were used to isolated cDNA samples. Real time PCR were used to study the gene expression of TERF2 in cALL. Results were standardized using B2M transcripts as an internal control. Relative quantification of the gene expression was calculated by using the delta-delta Ct method. TERF2 was up-regulated significantly in cALL patients compared to control samples of which p-value=0.002859, (p<0.05). Over-expression of TERF2 was observed in TEL-AML1 subgroup of which p-value=0.0002, (p<0.05). In contrast, under-expression of TERF2 was found in those having BCR-ABL1 fusion transcripts of which p-value=0.0221, (p<0.05). TERF2 also have found to have a better survival advantages for cALL patients. Over-expression of TERF2 is associated with good prognosis in cALL whilst under-expression is associated with poor prognosis in cALL patients. Measurement of TERF2 gene expression allows proper stratification of cALL subtypes into its respective prognostic indicator classification.