Genetic analysis of the 2q33 region containing CD28-CTLA4-ICOS genes: association with non-Hodgkin's lymphoma

Association of CTLA-4 polymorphisms with hematologic malignancy susceptibility: a meta-analysis

Background

Recent studies have reported an association between Cytotoxic T-lymphocyte antigen-4 (CTLA-4) polymorphisms and hematologic malignancy susceptibility, while the results remain inconsistent. Hence, we performed a meta-analysis to investigate the association between CTLA-4 polymorphisms with hematologic malignancy susceptibility.

Methods

A comprehensive and systematic search of Cochrane Library, PubMed, Embase databases was performed up to Sep. 20, 2024. The pooled odds ratio (OR) and its 95% confidence interval (CI) were used to determine the strength of the association between CTLA-4 polymorphisms and hematologic malignancy susceptibility. Statistical analysis was performed in STATA 12.0.

Results

A total of 13 studies concerning the CTLA-4 49A/G, CTLA-4 60A/G, CTLA-4 318T/C, CTLA-4 1661A/G, and CTLA-4 319C/T polymorphisms were included in the meta-analysis. The pooled results suggested the CTLA-4 49A/G polymorphism was significantly associated with an increased hematologic malignancy risk (AA vs. GA+GG: OR = 1.77, 95% CI = 1.56-2.02), especially in NHL, multiple myeloma, and leukemia. Similarly, CTLA-4 319C/T polymorphism was found to be associated with decreased chronic lymphocytic leukemia risk. There was no significant association between the CTLA-4 60A/G, 318T/C, and 1661A/G polymorphism and hematologic malignancy risk.

Conclusion

CTLA-4 49A/G and 319C/T polymorphisms were associated with hematologic malignancy susceptibility.

Impact of the cytotoxic T-lymphocyte associated antigen-4 rs231775 A/G polymorphism on cancer risk

Background

Cytotoxic T-lymphocyte associated antigen-4 (CTLA-4) is an immunosuppressive checkpoint that is involved in the development and metastasis of cancers. Several studies revealed that CTLA-4 rs231775A/G polymorphism may be associated with the risk of cancer in some populations, but the conclusions of these studies are not consistent.

Methods

We conducted a pooled analysis with eligible studies to explore the association between the CTLA-4 rs231775 variant and cancer risk. Additionally, we used in silico tools to evaluated the expression of CTLA-4 on urinary system cancer. Moreover, we adopted the enzyme-linked immunosorbent assay (ELISA), and Gene Set Enrichment Analysis (GSEA) to investigate the effects of CTLA-4 on bladder cancer (BLCA).

Results

In total, 92 case-control studies involving 29,987 patients with cancer and 36,484 healthy individuals (controls) were included in the pooled analysis. In the stratified analysis based on cancer type, the rs231775 A/G polymorphism was associated with increased bladder cancer risk in the heterozygote contrast model (OR = 1.23, 95% CI = 1.01-1.51, P = 0.040). The race-stratified analysis revealed that East Asians with the GG genotype had a 12% lower risk of developing cancer than those with the GA + AA genotype (95% CI = 0.81-0.95, P = 0.001). The in silico analysis showed that CTLA-4 expression was augmented in patients with BLCA. The ELISA results revealed that CTLA-4 expression was reduced in patients with BLCA carrying the AA genotype. Several signaling pathways, including cytokine-cytokine receptor interactions and T-cell receptor signaling, were associated with CTLA-4 expression.

Conclusion

The CTLA-4 rs231775 A/G polymorphism is associated with cancer risk in East Asian population. This polymorphism is especially associated with BLCA.

Genetic variants of CTLA4 are associated with clinical outcome of patients with multiple myeloma

Immune dysfunction in patients with multiple myeloma (MM) affects both the innate and adaptive immune system. Molecules involved in the immune checkpoint pathways are essential to determine the ability of cancer cells to escape from the immune system surveillance. However, few data are available concerning the role of these molecules in predicting the kinetics of progression of MM. We retrospectively analysed polymorphisms of CTLA4 (rs231775 and rs733618), BTLA (rs9288953), CD28 (rs3116496), PD-1 (rs36084323 and rs11568821) and LAG-3 (rs870849) genes in 239 patients with newly diagnosed MM. Patients with a CTLA4 rs231775 AA/AG genotype showed a median progression-free survival (PFS) significantly lower than those with GG genotype (32.3 months versus 96.8 months respectively; p: 0.008). The 5-year PFS rate was 25% for patients with grouped AA and AG genotype vs 55.4% for patients with GG genotype. Multivariate analysis confirmed the CTLA4 rs231775 genotype as an independent risk factor for PFS (Hazard Ratio (HR): 2.05; 95% CI: 1.0-6.2; p: 0.047). Our results suggest that the CTLA4 genotype may identify patients with earlier progression of MM. This polymorphism could potentially be used as a prognostic biomarker.

Comprehensive Analysis of 29,464 Cancer Cases and 35,858 Controls to Investigate the Effect of the Cytotoxic T-Lymphocyte Antigen 4 Gene rs231775 A/G Polymorphism on Cancer Risk

In our previous studies, we found that the rs231775 polymorphism of cytotoxic T-lymphocyte antigen 4 (CTLA-4) is associated with risks of different cancer types; however, the association remains controversial and ambiguous, so we conducted an in-depth meta-analysis to verify the association. A complete search of the PubMed, Google Scholar, Embase, Chinese databases, and Web of Science was conducted without regard to language limitations, covering all publications since November 20, 2021. The search criteria for cancer susceptibility associated with the polymorphism in the CTLA-4 gene rs231775 resulted in 87 case-control studies with 29,464 cases and 35,858 controls. The association strength was analyzed using odds ratios and 95% confidence intervals. Overall, we found that the CTLA-4 rs231775 polymorphism may reduce cancer risk. A stratified cancer type analysis showed that CTLA-4 rs231775 polymorphism was a risk factor for colorectal cancer and thyroid cancer; on the other hand, it was a protective factor for breast cancer, liver cancer, cervical cancer, bone cancer, head and neck, and pancreatic cancer. We also classified cancer into five systems and observed an increased association with digestive tract cancer, decreased associations with orthopedic tumors, tumors of the urinary system, and gynecological tumors. In the subgroup based on race, decreased relationships were observed in both Asians and Caucasians. The same decreased association was also shown in the analysis of the source of control analysis. Our present study indicates that the CTLA-4 rs231775 polymorphism contributes to cancer development and aggression.

Immune Checkpoint Molecules-Inherited Variations as Markers for Cancer Risk

In recent years, immunotherapy has been revolutionized by a new approach that works by blocking receptors called immune checkpoints (IC). These molecules play a key role in maintaining immune homeostasis, mainly by suppressing the immune response and by preventing its overactivation. Since inhibition of the immune response by IC can be used by cancer to avoid recognition and destruction by immune system, blocking them enhances the anti-tumor response. This therapeutic approach has brought spectacular clinical effects. The ICs present heterogeneous expression patterns on immune cells, which may affect the effectiveness of immunotherapy. The inherited genetic variants in regulatory regions of ICs genes can be considered as potential factors responsible for observed inter-individual differences in ICs expression levels on immune cells. Additionally, polymorphism located in exons may introduce changes to ICs amino acid sequences with potential impact on functional properties of these molecules. Since genetic variants may affect both expression and structure of ICs, they are considered as risk factors of cancer development. Inherited genetic markers such as SNPs may also be useful in stratification patients into groups which will benefit from particular immunotherapy. In this review, we have comprehensively summarized the current understanding of the relationship between inherited variations of CTLA-4, PDCD1, PD-L1, BTLA, TIM-3, and LAG-3 genes in order to select SNPs which can be used as predictive biomarkers in personalized evaluation of cancer risk development and outcomes as well as possible response to immunotherapy.

Subclonal mutation selection in mouse lymphomagenesis identifies known cancer loci and suggests novel candidates

Determining whether recurrent but rare cancer mutations are bona fide driver mutations remains a bottleneck in cancer research. Here we present the most comprehensive analysis of murine leukemia virus-driven lymphomagenesis produced to date, sequencing 700,000 mutations from >500 malignancies collected at time points throughout tumor development. This scale of data allows novel statistical approaches for identifying selected mutations and yields a high-resolution, genome-wide map of the selective forces surrounding cancer gene loci. We also demonstrate negative selection of mutations that may be deleterious to tumor development indicating novel avenues for therapy. Screening of two BCL2 transgenic models confirmed known drivers of human non-Hodgkin lymphoma, and implicates novel candidates including modifiers of immunosurveillance and MHC loci. Correlating mutations with genotypic and phenotypic features independently of local variance in mutation density also provides support for weakly evidenced cancer genes. An online resource http://mulvdb.org allows customized queries of the entire dataset.

Evidence implicating cancer drivers can be sparse when limited to clonal events. Here, the authors present a retrovirus driven in vivo lymphomagenesis time course including hundreds of thousands of subclonal mutations and demonstrate the utility of these in mapping the selective forces affecting cancer gene loci, including negatively selected mutations.

Biomarkers for checkpoint inhibition in hematologic malignancies

In the past few years we have seen remarkable paradigm shifts in the treatment of many solid tumors due to the introduction of inhibitors targeting immune checkpoints such as PD-1/PD-L1 and CTLA-4. Recent results indicate that checkpoint inhibition also represents a very promising approach for certain types of hematologic malignancies. Unfortunately, treatment with checkpoint inhibitors is also associated with substantial toxicities and high costs and only a subset of patients appears to derive clinical benefit from these treatments. This demonstrates the urgent need for biomarkers for the identification of patient populations that are likely to respond to this type of therapy and/or have fewer side effects. Here, we have reviewed available information on the prognostic and predictive value of biomarkers for anti-CTLA-4 and anti-PD-1/PD-L1 as the most commonly used checkpoint inhibitors. There are currently no reliable biomarkers capable of predicting responses to anti-CTLA-4 agents, such as ipilimumab, in hematologic malignancies. Certain polymorphisms in the CTLA-4 gene, however, seem to have an impact on the patients' outcome, especially in the case of chronic lymphocytic leukemia (CLL). There is now sufficient data supporting PD-L1 expression levels in the tumor tissue as an independent prognostic factor in B cell lymphomas such as diffuse large B-cell lymphoma (DLBCL). Overexpression of PD-L1 in the tumor tissue and elevated serum levels of soluble PD-L1 may also represent adverse prognostic factors in certain subtypes of T cell lymphomas. Finally, expression levels of PD-L1 also seem to predict responses to anti-PD-1/PD-L1 approaches in patients with Hodgkin lymphoma. Future studies will have to further delineate the prognostic/predictive role of PD-L1 expression as a biomarker in hematologic malignancies and may be able to identify confounding variables, which will hopefully to some extent be generalizable to other types of anti-tumor immunotherapies.

Genetic Variation of Costimulatory Molecules, Including Cytotoxic T-Lymphocyte Antigen 4, Inducible T-Cell Costimulator, Cluster Differentiation 28, and Programmed Cell Death 1 Genes, in Iranian Patients With Leukemia

OBJECTIVES

There are limited studies about the possible relationship between genetic variations of costimulatory genes and susceptibility to hematologic malignancies like leukemia and lymphoma.

MATERIALS AND METHODS

This cross-sectional study included 59 leukemia patients. The polymorphisms of costimulatory molecules, including the CTLA-4 gene (-318 C/T, -1722 T/C, -1661 A/G, +49 A/G), PD-1 gene (1.3 A/G, 1.9 C/T), ICOS gene (1720 C/T), and CD28 gene (17 C/T), were analyzed by polymerase chain reaction-restriction fragment length polymorphism methods.

RESULTS

Our results showed that the TT genotype and T allele of the CTLA-4 -318 T/C polymorphism, the AA genotype of CTLA-4 +49 A/G polymorphism, and the CT genotype of PD-1 1.9 C/T polymorphism were significantly higher in healthy controls (P < .05). However, the AG genotype of the CTLA-4 +49 A/G, the CC genotype of the PD-1 1.9 C/T, and the CT genotype of the CD28 +17C/T polymorphism were significantly increased in patients with leukemia (P < .05). When the genotype frequency of costimulatory genes was compared between different leukemia groups, we observed that the A allele of the CTLA-4 +49 A/G and the CC genotype and C allele of the CD28 +17 C/T polymorphism were significantly higher in patients with acute leukemia than in those with chronic leukemia (P < .05). Among leukemia patients, the AA genotype of CTLA-4 +49A/G polymorphism was significantly increased in patients with acute myeloid leukemia, whereas the AG genotype was more prevalent in patients with acute lymphoblastic leukemia (P < .05).

CONCLUSIONS

We show for the first time that genetic variations of costimulatory molecules CTLA-4, CD28, and PD-1 may be associated with susceptibility of Iranian patients to leukemia.

Is the Genetic Background of Co-Stimulatory CD28/CTLA-4 Pathway the Risk Factor for Prostate Cancer?

The impairment of immunological surveillance caused by aberrant T cell activation can lead to an inadequate anti-tumor response. Therefore, deregulation in co-stimulatory pathway might be associated with cancer susceptibility. Here we undertook a prospective study to investigate whether genetic variations in gene encoding molecule CD28 and CTLA-4 playing pivotal role in regulating adoptive immune response can influence susceptibility to prostate cancer. Single nucleotide polymorphisms (SNPs) in CTLA-4 and CD28 genes were genotyped in 301 prostate cancer (PCa) patients and 301 controls. The distributions of the genotypes and haplotypes in the CTLA-4/CD28 SNPs were similar in both studied groups. However, the overrepresentation of carriers of CTLA-4c.49A>G[A] allele and carriers of CTLA-4g.319C>T[T] allele in PCa as compared to controls was observed (p = 0.082 and p = 0.13, respectively). The risk of disease was higher (OR 1.78) for carriers of both susceptibility alleles as compared to carriers of protective genotypes (p = 0.03). The CTLA-4c.49A>G and CTLA-4g.319C>T SNPs might be considered as low risk susceptibility locus for PCa.

Lack of association between cytotoxic T-lymphocyte antigen-4 gene polymorphisms and lymphoid malignancy risk: evidence from a meta-analysis

Cytotoxic T-lymphocyte antigen-4 (CTLA-4) polymorphisms have been associated with susceptibility to lymphoid malignancies. However, results from the published single studies are inconsistent. Therefore, the present meta-analysis was conducted to get a more accurate estimation of the relationship between CTLA-4 gene polymorphisms and the lymphoid malignancy risk. We identified nine independent studies accounting for 3090 subjects up to January 30, 2016. Summary odds ratios (OR) and 95 % confidence intervals (CI) were used to evaluate the risk of lymphoid malignancies. Overall, no significant association was found between +49A/G (rs231775), -318C/T (rs5742909), and +6230A/G (rs3087243) CTLA-4 gene polymorphisms and lymphoid malignancies. Furthermore, ethnicity (Asian and Caucasian) and histopathology subgroup analyses (non-Hodgkin's lymphoma) also failed to detect an association between the studied polymorphisms and lymphoid malignancy risk. Our study shows that common CTLA-4 gene polymorphisms may not contribute to lymphoid malignancy susceptibility based on the current evidence.

Association between cytotoxic T lymphocyte antigen-4 +49A/G, -1722T/C, and -1661A/G polymorphisms and cancer risk: a meta-analysis

Cytotoxic T lymphocyte antigen-4 (CTLA-4), a key gene that contributes to the susceptibility and clinical course of cancer, is an important down-regulator of T cell activation and proliferation. The +49A/G polymorphism is commonly studied because of its association with cancer risks. However, other polymorphisms, such as -1722T/C and -1661A/G, have not been studied in detail. We performed a meta-analysis using 43 eligible case-control studies with a total of 19,089 patients and 21,388 controls to examine the association between CTLA-4 +49A/G, -1722T/C, and -1661A/G polymorphisms and cancer risk. We searched the PubMed and EMBASE databases for all articles published up to July 17, 2013. Individuals with the +49 A allele (AA/AG vs. GG, odds ratio (OR) = 1.21, 95% confidence interval (95% CI) = 1.16-1.27) and -1661 G allele (AG/GG vs. AA, OR = 1.52, 95% CI = 1.34-1.73) had increased cancer risk. However, no significant association between cancer risk and the -1722T/C polymorphism was found (CC/CT vs. TT, OR = 1.04, 95% CI = 0.92-1.16). In subgroup analysis for the +49A/G polymorphism, increased cancer risk remained in the subgroups of Asians (OR = 1.25, 95 % CI = 1.18-1.31), patients with breast cancer (OR = 1.28, 95% CI = 1.15-1.42), and patients with lung cancer (OR = 1.20, 95 % CI = 1.07-1.35). For the -1661A/G polymorphism, increased cancer risk remained in the subgroups of Asians (OR = 1.52, 95% CI = 1.34-1.73), patients with breast cancer (OR = 1.48, 95% CI = 1.07-2.03), and patients with oral cancer (OR = 3.16, 95% CI = 1.84-5.45). However, no significant increase in cancer risk was found in the subgroups for the -1722T/C polymorphism. In conclusion, the results suggest that +49A/G and -1661A/G polymorphisms in CTLA-4 are risk factors for cancers, whereas the -1722T/C polymorphism is not associated with an increased risk of cancer.

Genetic variations in CTLA-4, TNF-α, and LTA and susceptibility to T-cell lymphoma in a Chinese population

OBJECTIVE

T-cell lymphoma is a highly aggressive malignant lymphoma that is rare in Caucasians but relatively common in Asian populations. Factors regulating T-cell proliferation and function may play an important role in the pathogenesis of T-cell lymphoma.

METHODS

A total of 8 single nucleotide polymorphisms in cytotoxic T lymphocyte antigen-4 (CTLA-4), tumor necrosis factor-α (TNF-α), and lymphotoxin-α (LTA) genes were detected by polymerase chain reaction-ligation detection reaction analysis in a Chinese population of 291 patients with T-cell lymphoma and 300 healthy controls. Logistic regression was used to determine the odds ratios (ORs) and 95% confidence intervals for the associations of genotypes and haplotypes with T-cell lymphoma risk.

RESULTS

Among these polymorphisms, the LTA +252AA genotype was significantly associated with T-cell lymphoma risk (OR, 2.3; P=0.002). Furthermore, the TNF-α/LTA haplotype C-G-G-A (TNF-α -857C, -308G, and -238G and LTA +252A) showed a significantly increased risk for T-cell lymphoma (OR, 1.6; P=0.001).

CONCLUSION

Our study suggested that the LTA +252G>A polymorphism may influence susceptibility to T-cell lymphoma in the Chinese population.

Association of cytotoxic T-lymphocyte antigen 4 genetic polymorphism, hepatitis C viral infection and B-cell non-Hodgkin lymphoma: an Egyptian study

Abstract Genetic and environmental factors are involved in the pathogenesis of non-Hodgkin lymphoma (NHL). The present study aimed to investigate the association between cytotoxic T-lymphocyte antigen 4 (CTLA-4) genetic polymorphism, hepatitis C virus (HCV) infection and B-cell NHL risk in Egypt. Genotyping of CTLA-4 single nucleotide polymorphisms (SNPs) was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay for 181 adult patients with B-NHL and 200 controls. Our study revealed that CTLA-4 + 49 A/G polymorphism conferred increased risk of B-NHL (odds ratio [OR] = 1.7, 95% confidence interval [CI] = 1.36-2.565). The prevalence of HCV infection in individuals harboring the mutant genotype + 49 A/G and - 318 C/T SNPs was higher in patients with B-NHL and was associated with increased risk of B-NHL (OR = 2.79, 95% CI = 1.24-6.93 for + 49 A/G and OR = 3.9, 95% CI = 1.01-15.98 for - 318 C/T). In conclusion, some SNPs of CTLA-4 are genetic risk factors for B-NHL. Moreover, this study identified an association of CTLA-4 + 49 A/G and - 318 C/T promoter polymorphisms with HCV infection.

The expression, function, and clinical relevance of B7 family members in cancer

The modulation and suppression of anti-tumor immune responses is a characteristic feature of tumor cells to escape immune surveillance. Members of the B7 family are involved in this process, since the level of activation of the anti-tumor immune response depends on the balance between co-stimulatory and co-inhibitory signals. Some molecules are often overexpressed in tumors, which has been associated with the pathogenesis and progression of malignancies as well as their immunological and non-immunological functions. The B7 homologs play a key role in the maintenance of self-tolerance and the regulation of both innate and adaptive immunity in tumor-bearing hosts. Furthermore, the blockade of negative signals mediated by the interaction of co-inhibitory ligands and counter-receptors of the B7 family is currently being studied as a potential immunotherapeutic strategy for the treatment of cancer in humans.

Variations in suppressor molecule ctla-4 gene are related to susceptibility to multiple myeloma in a polish population

Various phenotype and functional T-cell abnormalities are observed in multiple myeloma (MM) patients. The aim of this study was to investigate the association between polymorphisms in the gene encoding cytotoxic T-lymphocyte antigen-4 (CTLA-4), a negative regulator of the T-lymphocyte immune response and susceptibility to multiple myeloma in a Polish population. Two hundred MM patients and 380 healthy subjects were genotyped for the following polymorphisms: CTLA-4c.49A>G, CTLA-4g.319C>T, CTLA-4g.*642AT(8_33), CT60 (CTLA-4g.*6230G>A), Jo31 (CTLA-4g.*10223G>T). Our study is the largest and most comprehensive evaluation to date of the association between genetic polymorphisms in the CTLA-4 molecule and multiple myeloma. It was found that CTLA-4c.49A>G[G], CT60[G], and Jo31[G] alleles were more frequently observed in MM patients than in controls (0.50 vs. 0.44, p = 0.03, 0.65 vs. 0.58, p = 0.04, and 0.63 vs. 0.57, p = 0.03, respectively). Moreover, the haplotype CTLA-4c.49A>G[G], CTLA-4g.319C>T[C], CTLA-4g.*642AT(8_33) [8], CT60[G], Jo31[G] including all susceptibility alleles increases the risk of MM about fourfold (OR: 3.79, 95%CI: 2.08–6.89, p = 0.00001). These findings indicate that genetic variations in the CTLA-4 gene play role in susceptibility to multiple myeloma and warrant further investigation through replication studies.

CTLA-4, CD28, and ICOS gene polymorphism associations with non-small-cell lung cancer

Polymorphisms in genes encoding CD28, ICOS, and CTLA-4 were demonstrated to be associated with susceptibility to malignancies. To the best of our knowledge, no study on this association has been performed in a Caucasian population for non-small-cell lung cancer (NSCLC). In the present work, we investigated the polymorphisms CTLA-4c.49A>G (rs231775), CTLA-4g.319C>T (rs5742909), CTLA-4g.*642AT(8_33), CTLA-4g.*6230G>A (CT60) (rs3087243), CTLA-4g.*10223G>T (Jo31) (rs11571302), CD28c.17+3T>C (rs3116496), and ICOSc.1554+4GT(8_15) in 208 NSCLC patients and 326 controls. The distributions of the allele and genotype were similar in both groups for CTLA-4, CD28, and ICOS gene polymorphisms. However, we noted a tendency toward overrepresentation of individuals possessing the CTLA-4c.49A>G[A] allele in NSCLC patients compared with controls (0.84 vs 0.79, p = 0.09). The association became significant compared with controls in women for the CTLA-4c.49A>G[A] allele and CTLA-4c.49A>G[AA] genotype (0.67 vs 0.54, p = 0.01, and 0.47 vs 0.30, p = 0.02; respectively). Moreover, the constellation of alleles CTLA-4c.49A>G[A]/CT60[G]/CD28c.17+3T>C[T]/ICOSc.1554+4GT(8_15)[>10] increased the risk of NSCLC about 2-fold (p = 0.002). The same constellation of alleles combined with smoking, CTLA-4g.319C>T[T], and ICOSc.1554+4GT(8_15)[>10] was associated with a decreased overall survival rate. In conclusion, the constellation of specific alleles in CTLA-4, CD28, and ICOS genes contributes to the susceptibility and clinical course of NSCLC.

Polymorphisms in the CD28/CTLA4/ICOS genes: role in malignant melanoma susceptibility and prognosis?

The appearance of vitiligo and spontaneous regression of the primary lesion in melanoma patients illustrate a relationship between tumor immunity and autoimmunity. T lymphocytes play a major role both in tumor immunity and autoimmunity. CD28, Cytotoxic T lymphocyte antigen 4 (CTLA4) and inducible costimulator (ICOS) molecules are important secondary signal molecules in the T lymphocyte activation. Single nucleotide polymorphisms (SNPs) in the CD28/CTLA4/ICOS gene region were reported to be associated with several autoimmune diseases including, type-1 diabetes, SLE, autoimmune thyroid diseases and celiac disease. In this study, we investigated the association of SNPs in the CD28, CTLA4 and ICOS genes with the risk of melanoma. We also assessed the prognostic effect of the different polymorphisms in melanoma patients. Twenty-four tagging SNPs across the three genes and four additional SNPs were genotyped in a cohort of 763 German melanoma patients and 734 healthy German controls. Influence on prognosis was determined in 587 melanoma cases belonging to stage I or II of the disease. In general, no differences in genotype or allele frequencies were detected between melanoma patients and controls. However, the variant alleles for two polymorphisms in the CD28 gene were differentially distributed in cases and controls. Similarly no association of any polymorphism with prognosis, except for the rs3181098 polymorphism in the CD28 gene, was observed. In addition, individuals with AA genotype for rs11571323 polymorphism in the ICOS gene showed reduced overall survival. However, keeping in view the correction for multiple hypothesis testing our results suggest that the polymorphisms in the CD28, CTLA4 and ICOS genes at least do not modulate risk of melanoma and nor do those influence the disease prognosis in the investigated population.

Association of T-cell regulatory gene polymorphisms with oral squamous cell carcinoma

Costimulatory molecules have complementary effects on T-cell activation and their balance may control the development of oral cancer. The aim of this study was to determine the relevance of cytotoxic T-lymphocyte antigen 4 (CTLA-4), CD28 and inducible costimulator (ICOS) polymorphisms in oral squamous cell carcinoma (OSCC). Genotyping for CTLA-4 (-1661 A/G and +49 A/G), CD28 (0 C/G and +3160 G/T) and ICOS (+637 A/C and +1599 C/T) was performed in the 83 patients with OSCC, compared to the 40 unrelated healthy volunteers as controls. The genotype CTLA-4 -1661 was significantly different between the patient group and the control group. The allele CTLA-4 -1661 G was significantly found more frequent in patients with OSCC (p=0.001). In bivariate analysis, noticeable differences between OSCC and controls were seen. The combinations CTLA-4 -1661 G/G and CTLA-4 +49 A/G, ICOS +1559 C/T and ICOS +1559 C/C each with CTLA-4 -1661 G/G, ICOS +637 C/C and ICOS +637 A/C each with CTLA-4 -1661, CTLA-4 -1661 A/G and ICOS +637 C/C, CD28 +3160 G/T and CTLA-4 -1661 A/A and CD28 +3160 G/T and CTLA-4 -1661 A/G were seen in the patient group only. Especially the polymorphisms of the CTLA-4 -1661-genotype - alone and in combination with other T cell regulator polymorphisms - seem to be possible predisposing factors for OSCC. Therefore, they might be future targets for a primary prophylaxis or an individualised therapy.

Polymorphisms in the cytotoxic T-lymphocyte antigen 4 gene and cancer risk: a meta-analysis

BACKGROUND

Polymorphisms in the cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene have been implicated in susceptibility to cancer, but the many published studies have reported inconclusive results. The objective of the current study was to conduct a meta-analysis investigating the association between polymorphisms in the CTLA-4 gene and the risk of cancer.

METHODS

The PubMed and EMBASE databases were searched for all articles published up to September 19, 2010 that addressed cancer and polymorphisms, variants, or mutations of CTLA-4. A statistical analysis was performed using proprietary statistical software.

RESULTS

Three polymorphisms (+49 adenine/guanine [+49A/G], -318 cytosine/thymine [-318C/T], and the +6230G/A polymorphism [CT60]) in 48 case-control studies from 27 articles were analyzed. The results indicated that individuals who carried the +49 G allele (AG + GG) had a 16% decreased risk of cancer compared with homozygotes (+49AA; odds ratio [OR], 0.84; 95% confidence interval [CI], 0.74-0.95). However, there was no significant association between the risk of cancer and the -318C/T polymorphism or the CT60 polymorphism (-318C/T: OR, 1.23; 95% CI, 0.99-1.54 for TT + TC vs CC; CT60: OR, 1.02; 95% CI, 0.80-1.29 for AA + AG vs GG). In further stratified analyses for the +49A/G and -318C/T polymorphisms, the decreased risk of cancer remained in subgroups of Europeans, patients with breast cancer, and patients with lung cancer for the +49A/G polymorphism; whereas an increased risk of cancer was observed among Europeans for the -318C/T polymorphism.

CONCLUSIONS

Results from the current meta-analysis suggested that the +49A/G and -318C/T polymorphisms in CTLA-4 are risk factors for cancer. To further evaluate gene-gene and gene-environment interactions between CTLA-4 polymorphisms and the risk of cancer, more studies with larger groups of patients will be required.

Association between the Cytotoxic T-lymphocyte antigen 4 +49G > A polymorphism and cancer risk: a meta-analysis

Background

As a key gene in the immunosurveillance of cell malignancy, Cytotoxic T-lymphocyte antigen 4 (CTLA-4 is an important negative regulator of T cell activation and proliferation. The CTLA-4 +49G > A polymorphism is one of the most commonly studied polymorphisms in this gene due to its association with cancer risks, but previous results have been conflicting.

Methods

We preformed a meta-analysis using 22 eligible case-control studies (including 32 datasets) with a total of 11,273 patients and 13,179 controls to summarize the existing data on the association between the CTLA-4 +49G > A polymorphism and cancer risk.

Results

Compared with the common CTLA-4 +49G > A GG genotype, the carriers of variant genotypes (CTLA-4 +49 GC/CC) had a 1.24-fold elevated risk of cancer (95% CI = 1.18-1.32, P < 0.05) under the dominant genetic model, as estimated using a fixed effect model. The effect of the CTLA-4 +49G > A polymorphism was further evaluated using stratification analysis. In four breast cancer studies, patients with the variant genotypes had a significantly increased risk of breast cancer (OR = 1.31, 95% CI = 1.17-1.48, P < 0.00001). A similar result was found in three skin cancer studies (OR = 1.30, 95% CI = 1.10-1.52, P = 0.001). In 26 solid tumor studies, subjects with the variant genotypes had a significantly higher risk of developing solid tumors (OR = 1.25, 95% CI = 1.18-1.33, P < 0.00001) compared with the 6 non-solid tumor studies (OR = 1.08, 95% CI = 0.79-1.48, P = 0.62). Patients with variant genotypes had significantly increased risk of non-epithelial tumors and epithelial tumors, with ORs of 1.23 (95% CI = 1.14-1.32, P < 0.00001) and 1.29 (95% CI = 1.17-1.41, P < 0.00001), respectively. It was also demonstrated that the increased risk of cancer associated with CTLA-4 +49G > A variant genotypes was more pronounced in Caucasians (OR = 1.29, 95% CI = 1.13-1.47, P = 0.0002), Asians (OR = 1.23, 95% CI = 1.16-1.32, P < 0.00001) and Chinese (OR = 1.23, 95% CI = 1.15-1.31, P < 0.00001).

Conclusion

Our meta-analysis suggests that the CTLA-4 +49G > A polymorphism genotypes (GA + AA) might be associated with an increased risk of cancer, especially in Caucasians and Chinese.

CTLA-4 +49A>G polymorphism is associated with the risk but not with the progression of colorectal cancer in Chinese

PURPOSE

Colorectal cancer (CRC) is one of the most common malignancies in the world and a multipathway disease. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is a potent immunoregulatory molecule that suppresses antitumor response by down-regulating T-cell activation. The most studied +49A>G polymorphism of CTLA-4 gene has been associated with several autoimmune or cancer diseases. Our aim was to investigate the association between this genetic variant and the risk as well as progression of colorectal cancer in Chinese.

METHODS

We conducted a case-control study of 124 colorectal cancer cases and 407 healthy controls. DNA was extracted from blood specimens, and +49A>G polymorphism in the CTLA-4 gene was genotyped by polymerase chain reaction-ligation detection reaction (PCR-LDR).

RESULTS

In our study group, the frequency of AG or GG or carrying at least one G allele at position +49 was significantly different in colorectal cancer patients and the control group, indicating that the risk of CRC was significantly higher among subjects with the AG or GG genotype or carrying at least one G allele at position +49 than among the subjects with the AA genotype. However, we observed no association between CTLA-4 +49A>G polymorphism and the progression of CRC. Interestingly, the CTLA-4 +49A allele was in non-significantly higher numbers in CRC patients with distant metastasis.

CONCLUSIONS

Our results suggested that CTLA-4 +49A>G polymorphism was associated with an increased risk of colorectal cancer, but this polymorphism did not play an important role in the progression of CRC in Chinese.

Investigation of CTLA-4 and CD28 gene polymorphisms in a group of Turkish patients with colorectal cancer

Colorectal cancer (CRC), also called colon cancer or bowel cancer, includes cancerous growths in the colon, rectum and appendix. The immune system is an important defence mechanism against cancer and is often dysfunctional in patients with malignancies. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and CD28 genes encode receptors that provide negative and positive signals, respectively. Polymorphisms in these genes can affect their functions. In this study, we aimed to investigate the association of cancer with the frequencies and roles of CTLA-4/+49A > G (exon 1) and -318C > T (promoter), and CD28/IVS3 + 17T > C (intron 3 position + 17). These polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 218 Turkish subjects (56 patients with CRC and 162 healthy controls). No statistically significant differences in the genotype distributions of CTLA-4/+49GG (1.8% vs. 6.8%, odds ratio (OR) = 0.250, P = 0.305) and CTLA-4/-318TT (0% vs. 0.6%, OR = 1.006, P = 1.000), and CD28/IVS3 + 17CC (8.9% vs. 3.7%, OR = 0.2411, P = 0.155) between patients with CRC and healthy controls, were observed. We also found that there were no significant differences in the frequencies of CTLA-4/+49G (18.8% vs. 20.1%, OR = 0.920, P = 0.891) and CTLA-4/-318T (7.1% vs. 4.3%, OR = 1.653, P = 0.314), and CD28/IVS3 + 17C alleles (25.9% vs. 19.1%, OR = 1.353, P = 0.139) between two study groups. Present results suggested that CTLA-4 and CD28 gene polymorphisms did not play an important role in Turkish patients with CRC.

Association between CTLA-4 gene promoter (49 A/G) in exon 1 polymorphisms and inflammatory bowel disease in the Tunisian population

BACKGROUND/AIM

To investigate the possible association between the polymorphism of the CTLA-4 exon 1 +49 A/G and susceptibility to Crohn's disease (CD) and ulcerative colitis (UC) in the Tunisian population.

METHODS

The +49 A/G dimorphism was analyzed in 119 patients with CD, 65 patients with UC, and 100 controls by the polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

Significantly higher frequencies of the CTLA-4 +49A allele and A/A homozygous individuals were observed in patients with CD when compared with controls (pc = 0.0023 and pc = 0.0003, respectively). Analysis of CTLA-4 A/G polymorphism with respect to sex in CD showed a significant difference in A/A genotypes between female patients and controls (pc = 0.0001 and pc = 0.038, respectively). There were no differences in the subgroups of patients with CD.

CONCLUSIONS

Forty-nine A alleles and AA genotype are associated with CD susceptibility in Tunisians. Other genes involved in the T-cell regulation remain strong candidates for IBD susceptibility and require further investigation.

Genetic variants in T helper cell type 1, 2 and 3 pathways and gastric cancer risk in a Polish population

Host immune responses are known determinants of gastric cancer susceptibility. We previously reported an increased gastric cancer risk associated with common variants of several T helper type 1 (Th1) cytokine genes in a population-based case-control study in Warsaw, Poland. In the present study, we augmented our investigation to include additional Th1 genes as well as key genes in the Th2 and Th3 pathways. Analysis of 378 cases and 435 age- and sex-matched controls revealed associations for polymorphisms in the Th1 IL7R gene and one polymorphism in the Th2 IL5 gene. The odd ratios (ORs) for IL7R rs1494555 were 1.4 [95% confidence interval (CI), 1.0-1.9] for A/G and 1.5 (95% CI, 1.0-2.4) for G/G carriers relative to A/A carriers (P = 0.04). The ORs for IL5 rs2069812 were 0.9 (95% CI, 0.7-1.3) for C/T and 0.6 (95% CI, 0.3-1.0) T/T carriers compared with C/C carriers (P = 0.03). These results suggest that IL5 rs2069812 and IL7R rs1389832, rs1494556 and rs1494555 polymorphisms may contribute to gastric cancer etiology.

Genetic susceptibility to lymphoma

Genetic susceptibility studies of lymphoma may serve to identify at risk populations and clarify important disease mechanisms. This review considered all studies published through October 2006 on the contribution of genetic polymorphisms in the risk of lymphoma. Numerous studies implicate the role of genetic variants that promote B-cell survival and growth with increased risk of lymphoma. Several reports including a large pooled study by InterLymph, an international consortium of non-Hodgkin lymphoma (NHL) case-control studies, found positive associations between variant alleles in TNF -308G>A and IL10 -3575T>A genes and risk of diffuse large B-cell lymphoma. Four studies reported positive associations between a GSTT1 deletion and risk of Hodgkin and non-Hodgkin lymphoma. Genetic studies of folate-metabolizing genes implicate folate in NHL risk, but further studies that include folate and alcohol intakes are needed. Links between NHL and genes involved in energy regulation and hormone production and metabolism may provide insights into novel mechanisms implicating neuro- and endocrine-immune cross-talk with lymphomagenesis. However, this links will need replication in larger populations. Numerous studies suggest that common genetic variants with low penetrance influence lymphoma risk, though replication studies will be needed to eliminate false positive associations.

Association of T-cell regulatory gene polymorphisms with susceptibility to gastric mucosa-associated lymphoid tissue lymphoma

PURPOSE

Helicobacter pylori infection and host susceptibility interact to develop gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and activation of specific T cells might play a crucial role in this process. Recent investigations show that the CTLA4, CD28, and ICOS genes are located on chromosome 2q33 and their polymorphisms confer susceptibility to infectious and immune diseases through deregulation of T-cell stimulation. We aimed to determine the role of CTLA4, CD28, and ICOS polymorphisms in gastric MALT lymphoma.

PATIENTS AND METHODS

Genotyping for CTLA4 (49 A/G, -318 C/T, and CT60 A/G), CD28 (IVS3+ 17T/C), and ICOS (c.602 A/C and c.1624C/T) was performed for 62 patients with gastric MALT lymphoma and compared with 250 unrelated healthy controls.

RESULTS

H pylori infection was significantly higher in patients with gastric MALT lymphoma (90.3%) compared with controls (66.4%; P < .001). The CTLA4 -318 C/T genotype was associated with a lower risk of developing gastric MALT lymphoma (odds ratio [OR] = 0.3; P = .022), whereas CTLA4 49 G/G genotype was linked to a higher risk (OR = 4.1; P = .044). In patients with H pylori infection, CTLA4 49 G/G genotype was associated with an even higher risk (OR = 6.4; P = .047). Carriage of the tightly linked -318C -49G haplotype conferred a four-fold higher susceptibility to MALT lymphoma (OR = 4.2; P = .042). Complete remission after H pylori eradication was related to tumor stage but not to genotypes or haplotypes.

CONCLUSION

These results indicate a genetic link of CTLA4 gene polymorphisms to development of gastric MALT lymphoma and indirectly support the crucial role of host activated T cells in the MALT lymphomagenesis.