Interleukin-23 Receptor Gene Variants in Acute Lymphoblastic Leukemia and Their Relation to Prognostic Factors.

BACKGROUND Interleukin (IL)-23 has an important role in tumor immune regulation. OBJECTIVE To investigate the possible association of interleukin-23 receptor (IL23R) gene variants rs1884444, rs10889677 and rs11209026 with development of acute lymphoblastic leukemia (ALL). METHODS The IL23R variants were studied in 164 ALL patients and compared to 175 healthy controls by polymerase chain reaction-restriction fragment length polymorphism. The relationship between these variants and clinical and laboratory features of the patients and response to therapy were evaluated. RESULTS No significant differences in genotype and allele frequencies existed between patients and controls. The rs1884444TG genotype was significantly lower in patients who relapsed (24.2%) compared to those without relapse (55.9%, p=0.006). Fewer patients who relapsed had evidence of the G allele (p=0.034). The TG genotype was associated with a longer complete remission at 1804±116 days compared to other genotypes (<1217 days, p=0.028), however, this result was not significant in multivariate analysis. The rs10889677 AA genotype and A allele were associated with age (p<0.041) and platelet number (p=0.03) in precursor-B cell ALL (B-ALL) patients. Both occurred more frequently in patients aged 2-10 years (63.6% and 66%, respectively) and in those with platelets >100×10ˆ3 μL (68.4% and 52.4%, respectively). CONCLUSION Our findings showed a lack of association of the studied polymorphisms with the risk of ALL. The influence of the rs1884444 polymorphism on relapse rate and association of rs10889677 AA genotype with favorable prognostic factors suggest the effect of the studied polymorphisms on ALL response to therapy and prognosis.