The role of CTLA-4 exon-1 49 A/G polymorphism and soluble CTLA-4 protein level in egyptian patients with Behçet's disease

Genetics in Behcet's Disease: An Update Review

Behcet's disease (BD) is one of the most vision-threatening clinical entities of uveitis. Although the etiopathogenesis of BD remains obscure, accumulating evidence has demonstrated that both genetic and environmental factors may contribute to the development of BD. Genome-wide association studies (GWAS) and candidate association studies have identified several genetic variants strongly associated with BD, including variants in human leukocyte antigen (HLA) -A02, -A03, -A24, -A26, -A31, -B15, -B27, -B35, -B49, -B51, -B57, -B58, -C0704, CIITA, ERAP1, MICA, IL1A-IL1B, IL10, IL12, IL23R, IL-23R/IL-12RB2, IL1RL1-IL18R1, STAT4, TFCP2L1, TRAF5, TNFAIP3, CCR1/CCR3, RIPK2, ADO-ZNF365-EGR2, KLRC4, LACC1, MEFV, IRF8, FUT2, CEBPB-PTPN1, ZMIZ1, RPS6KA4, IL10RA, SIPA1-FIBP-FOSL1, VAMP1, JRKL/CTCN5, IFNGR1 and miRNA-146a. Epigenetic modifications are also reported to play essential roles in the development of BD, including DNA methylation and histone modification. We review here the recent advances in the genetic and epigenetic factors associated with the BD pathogenesis.

Association of CTLA-4 and IL-4 polymorphisms in viral induced liver cancer

Background

Hepatocellular carcinoma (HCC) is one of the most prevalent types of cancer and is responsible for close to one million annual deaths globally. In Pakistan, HCC accounts for 10.7% of cancer incidence. Prior studies indicated an association between interleukin 4 (IL-4) and cytotoxic T lymphocyte protein 4 (CTLA-4) gene polymorphisms in many types of cancers, including HCC that are either hepatitis B virus (HBV)- or hepatitis C Virus (HCV)-induced. The association of IL-4 and CTLA-4 genetic polymorphisms with HCV-induced HCC is not yet determined in the Pakistani population. Therefore, this research is designed to investigate the implication of IL-4 and CTLA-4 gene polymorphisms by determining the association of IL-4 -590 C/T (rs2243250) and CTLA-4 + 49 A/G (rs231775) with HCC in Pakistan.

Methods

Different bioinformatics tools were employed to determine the pathogenicity of these polymorphisms. Samples were collected from HCV-induced HCC patients, followed by DNA extraction and ARMS-PCR analysis.

Results

The SNP analysis results indicated a positive association of IL-4 -590C/T and CTLA-4 + 49A/G gene polymorphisms with HCV-induced HCC in Pakistan. The CTLA-4 polymorphism might enhance therapeutic efficiency of HCC chemotherapy medicines. The IL-4 polymorphism might introduce new transcription factor binding site in IL-4 promoter region.

Conclusion

This study delineated risk factor alleles in CTLA-4 and IL-4 genes associated with HCV-mediated HCC among Pakistani patients that may have application to serve as genetic markers for pre- and early diagnosis and prognosis of HCC in HCV patients.

Meta-analysis of the genetic association between PTPN22, CTLA-4 variants and risk of uveitis

BACKGROUND

Though the risk of PTPN22, CTLA-4 genetic variants with uveitis have been developed, the combined results still remain uncertain and controversial.

OBJECTIVES

To perform a meta-analysis to estimate the precise association of PTPN22 (rs2488457, rs2476601) and CTLA-4 (rs231775, rs5742909, rs4553808, and rs3087243) polymorphisms with uveitis susceptibility.

METHOD

Five electronic databases (PubMed, Embase, Web of Science, CBM, CNKI) were systematically searched for relevant literature up to July 20, 2021. All statistical analysis were evaluated by STATA 12.0 software and R programming language.

RESULTS

Our meta-results indicated that PTPN22 rs2488457 conferred positive susceptibility to uveitis (OR=1.18, 95%CI=1.02-1.38, p=0.029). In stratified analysis by ethnicity, rs2488457 C allele had a growing tendency towards uveitis in Asian region (OR=1.21, 95%CI=1.00-1.45, p=0.046). For CTLA-4 rs231775, subgroup analysis based on ethnicity manifested a negative association among uveitis individuals in Africa region (OR=0.25, 95%CI=0.19-0.33, p<0.001). For CTLA-4 rs4553808, subgroup analysis by disease type revealed that GG genotype was associated with an elevated risk of Behcet's disease (OR=3.22, 95%CI=1.05-9.90, p=0.042).

CONCLUSIONS

Our research revealed that PTPN22 rs2488457 conferred strong susceptibility to uveitis in general, especially in Asian region. CTLA-4 rs231775 conveyed protection against uveitis in African populations and CTLA-4 rs4553808 displayed an increased risk of Behcet's disease.

The potential of genetically guided treatment in Behçet's disease

Continuous identification of specific targets and candidate genes together with novel approaches offers new promises for the future of gene therapy design in Behçet's disease (BD). Personalized medicine based on pharmacogenomics is being developed at the clinical stage to improve treatment response. Screening the whole gene and regulatory regions is important when searching for novel variants associated with such complex diseases. Different host genetic factors play significant roles in susceptibility to BD. Thus, identifying these genes responsible for susceptibility and resistance to BD may offer a notable contribution toward understanding its pathogenesis, and may lead to the development of novel prophylactic and treatment strategies. Evidenced-based treatment strategy is recommended for the management in BD patients. This review sheds light on the immunopathogenesis and pharmacogenetics of BD with special attention to the treatment targeting gene polymorphisms. In conclusion, the potential of genetically guided treatment in BD takes us back to the future for an accurate management strategy of this serious rheumatic disease. The ongoing discovery of pivotal genes related to the susceptibility, manifestations, disease activity and treatment options provide substantial hope to the reduced frequency of BD, effective control and improvement in the prognosis. Targeted gene therapy could be a leading option in the treatment armamentarium of BD.