Molecular Assessment of Minimal Residual Disease in Iranian Pediatric Acute Lymphoblastic Leukemia Patients

Acute lymphoblastic leukemia (ALL) is the most common hematologic malignancy in children. TAL1 dysregulation drives 40–60% of T-ALL cases, but its utility as a minimal residual disease (MRD) biomarker remains controversial. We evaluated TAL1 expression in pediatric T-ALL patients. This case-control study analyzed TAL1 expression via RT-PCR in 50 T-ALL patients (new diagnosis, post-induction, relapse, aged 0–14 years) and 30 controls. SIL-TAL1 fusion status was assessed by using real-time polymerase chain reaction (RT-PCR). The study also assessed correlations between TAL1 expression and the patients’ demographic and laboratory characteristics. GAPDH served as the internal control gene. TAL1 was overexpressed in new diagnoses (5.2-fold vs. controls; p<0.001) and relapse (3.1-fold vs. post-induction; p<0.005). SIL-TAL1+ patients had higher relapse rates (HR=2.3; 95% CI:1.1–4.8). TAL1 overexpression correlates with disease activity in T-ALL, but SIL-TAL1 fusion may better predict relapse. Larger validation studies are needed. Or (These findings suggest that TAL1 overexpression is associated with disease burden and relapse, supporting its potential as a genetic MRD biomarker in Iranian pediatric ALL patients).