Determination of different T(9;22) transcripts and investigation of their relationship with treatment response in chronic myeloid leukemia patients

Chronic myeloid leukemia (CML) is a stem cell disease which develops with abnormal proliferation of myeloid cells. In CML, Philadelphia chromosome(Ph) is formed by translocation between q11 band of 22nd chromosome (BCR gene) and q34 band of 9th chromosome (ABL1 gene). Ph(+) cell induces clone proliferation and leucocytosis. In CML, fractures maybe occurred at different points of chromosomes and fusions of different fractures conclude different oncogenic products.Translation of each RNA transcripts from different BCR::ABL1 fusions results in different protein tyrosine kinases(PTKs). These PTKs can potentially affect biological features of disease and response to therapy.This study aimed to determine effects of different transcripts on diagnosis, treatment, course of disease and recurrence.Our study involved 182 samples which included different time points samples of 125 patients with CML. 111 of blood/bone marrow samples were Ph(+) diagnosis/follow up samples and 72 of 182 samples were collected during therapy resistance. All samples was evaluted by using RT-PCR in terms of p210(e14a2,e13a2,e14a3,e13a3), p190(e1a2,e1a3) and p230(e19a2,e19a3) fusions. In first admission samples, e14a2 %48,6, e13a2 %35,1, e14a2/e13a2 coexpression %15,3, and e13a2/atypical %0,9 were determined. In resistant samples, e14a2 %59,2, e13a2 %22,5, e14a2/e13a2 %8,4, e14a2/e1a2 %1,4 e13a2/e1a2 %1,4, e14a2/e19a2 %4,2, e14a2/e13a2/e1a2/e19a2 %1,4 ve e13a2/e18a2 %1,4 was detected.When primary samples compared with resistant samples; in resistant samples, the frequency of e13a2 and e14a2/e13a2 decreased, the frequency of e14a2 fusion increased, and the presence of atypical rare transcripts was observed. Accordingly, e14a2 fusion and atypical rare transcripts may be associated with resistance and low treatment response in CML.