Relationship Between Cytotoxic T-Lymphocyte-associated Antigen-4: Programmed Death-1 Genes Polymorphisms and Susceptibility to Pediatric B-Cell Acute Lymphoblastic Leukemia.

Programmed death-1 (PD1) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) have a vital role in immune checkpoint pathways. Single nucleotide polymorphisms (SNPs) of PD1 and CTLA4 have been reported to be associated with susceptibility to certain autoimmune diseases and cancers. The potential association between SNPs in these immune checkpoint genes and risk of acute lymphoblastic leukemia (ALL) still unclear. The aim of this study is to clarify the effect of PD1 and CTLA4 SNPs on the risk of developing ALL and the prognosis of the disease. The study was performed on 100 pediatric B-ALL patients and 100 controls. The PD1 and CTLA4 SNPs were examined by RFLP technique. The study revealed that CTLA4 (rs11571316) was associated with high risk of B-ALL developments OR 1.492 (CI: 1157 to 1924) ( P =0.002). PD1 (rs36084323) GA genotype was significantly associated with protective effect against nonremission ( P =0.007). PD1 (rs36084323) A allele were associated with protective effect against relapse ( P =0.008). CTLA4 and PD1 genotypes did not have significant impact on B-ALL patients outcome. The current study displayed for the first time that genetic variations of the CTLA-4, was associated with susceptibility to B-ALL and that PD1 (rs36084323) GA genotype was significantly associated with protective effect against nonremission, while PD1 (rs36084323) A allele was associated with protective effect against relapse.