CTLA-4 polymorphisms and haplotype correlate with survival in ALL after allogeneic stem cell transplantation from related HLA-haplotype-mismatched donor

Background

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been established as an effective treatment for patients with hematological malignancies. Disease relapse remains a major cause of transplant failure. T cell homeostasis is critical to determine the potency of the GVT effect. Recent studies have shown the association of the CTLA-4 polymorphisms with the outcome after HLA-identical sibling allogeneic HSCT.

Methods

In this study, we focused on four CTLA-4 polymorphisms, and analyzed the impact of donor genotypes and haplotypes on the conditions of 152 acute leukemia patients (ALL 83) after related HLA-haplotype- mismatched transplantation. The four SNP genotypes (−1661, −318, CT60 and +49) were determined by TaqMan SNP genotyping assays.

Results

ALL recipients of donors with +49 GG showed significantly lower OS (67.7 vs. 90.3 %, P = 0.015) than those with GA+AA. Multivariate analyses showed that +49 GG was an independent risk factor for OS (HR: 0.306, 95 % CI 0.111–0.842, P = 0.022) .23 ALL patients receiving mDLI showed significantly lower OS with +49 GG donor than those with GA+AA (30.0 vs. 83.1 %, P = 0.003). The haplotype analysis revealed only three haplotypes in the donor population −1661/−318/CT60/+49 i.e., ACGG, ACAA and GTGA, the frequencies were 64.1, 19.4 and 16.5 %, respectively. Donors with and without the ACGG/ACGG haplotype had the same effect on transplant outcomes as those with +49 GG and +49 GA+AA.

Conclusion

In summary, the CTLA-4 +49 GG and the haplotype ACGG/ACGG reduced the overall survival in ALL after allo-HSCT from the related HLA-haplotype-mismatched donor, knowledge of the CTLA-4 polymorphism and haplotype may provide useful information for donor selection and individual application of immunosuppressive agents and immunotherapy.

A meta-analysis of association between cytotoxic T lymphocyte associated antigen-4 polymorphisms and gastric cancer risk

AIM: To investigate the correlation between cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) gene polymorphisms and gastric cancer risk.

METHODS: Two reviewers independently searched PubMed, FMRS, CNKI, VIP and WanFang Data from January 1, 1990 to May 1, 2014 for case-control studies on the correlation between CTLA-4 gene polymorphisms and gastric cancer risk. According to inclusion and exclusion criteria, two reviewers independently screened the literature, extracted the data, and assessed the methodological quality. A meta-analysis was then performed using RevMan 5.2 software.

RESULTS: A total of 10 case-control studies concerning the CTLA-4 +49 A/G, CTLA-4 -1661A/G, CTLA-4 -1722T/C and CTLA-4 -318 T/C polymorphisms were included in the meta-analysis. The CTLA-4 +49 and CTLA-4 -318 alleles were not associated with genetic susceptibility to gastric cancer. The CTLA-4 -1661 A/G polymorphism was significantly associated with an increased gastric cancer risk (AG vs AA: OR = 2.04, 95%CI: 1.60-2.61, P < 0.00001; AG/GG vs AA: OR = 1.79, 95%CI: 1.43-2.25, P < 0.00001). The CTLA-4 -1722T/C polymorphism was also significantly associated with an increased gastric cancer risk (TT vs CC, OR = 1.66, 95%CI: 1.05-2.62, P = 0.03; TC vs CC, OR = 2.11, 95%CI: 1.05-4.24, P = 0.04; TT/TC vs CC, OR = 1.84, 95%CI: 1.20-2.82, P = 0.04).

CONCLUSION: The CTLA-4 +49 and CTLA-4 -318 alleles are not associated with genetic susceptibility to gastric cancer. The CTLA-4 -1661A/G and -1772T/C polymorphisms are associated with an increased risk of gastric cancer. CTLA-4 -1661 AG and GG allele carrying individuals may have increased incidence of gastric cancer. CTLA-4 -1772 allele carrying TT and TC may increase the incidence of gastric cancer in individuals.