Association of IL4, IL13, and IL4R polymorphisms with gastrointestinal cancer risk: A meta-analysis

The genetic polymorphisms of immune-related genes contribute to the susceptibility and survival of lymphoma

BACKGROUND

Though immunological abnormalities have been proven involved in the pathogenesis of lymphoma, the underlying mechanism remains unclear.

METHODS

We investigated 25 single nucleotide polymorphisms (SNPs) of 21 immune-related genes and explored their roles in lymphoma. The genotyping assay of the selected SNPs was used by the Massarray platform. Logistic regression and Cox proportional hazards models were used to analyze the associations of SNPs and the susceptibility of lymphoma or clinical characteristics of lymphoma patients. In addition, Least Absolute Shrinkage and Selection Operator regression was used to further analyze the relationships with the survival of lymphoma patients and candidate SNPs, and the significant difference between genotypes was verified by the expression of RNA.

RESULTS

By comparing 245 lymphoma patients with 213 healthy controls, we found eight important SNPs related to the susceptibility of lymphoma, which were involved in JAK-STAT, NF-κB and other functional pathways. We further analyzed the relationships between SNPs and clinical characteristics. Our results showed that both IL6R (rs2228145) and STAT5B (rs6503691) significantly contributed to the Ann Arbor stages of lymphoma. And the STAT3 (rs744166), IL2 (rs2069762), IL10 (rs1800871), and PARP1 (rs907187) manifested a significant relationship with the peripheral blood counts in lymphoma patients. More importantly, the IFNG (rs2069718) and IL12A (rs6887695) were associated with the overall survival (OS) of lymphoma patients remarkably, and the adverse effects of GC genotypes could not be offset by Bonferroni correction for multiple comparison in rs6887695 especially. Moreover, we determined that the mRNA expression levels of IFNG and IL12A were significantly decreased in patients with shorter-OS genotypes.

CONCLUSIONS

We used multiple methods of analysis to predict the correlations between lymphoma susceptibility, clinical characteristics or OS with SNPs. Our findings reveal that immune-related genetic polymorphisms contribute to the prognosis and treatment of lymphoma, which may serve as promising predictive targets.

Interleukins (Cytokines) as Biomarkers in Colorectal Cancer: Progression, Detection, and Monitoring

Cancer is the primary cause of death in economically developed countries and the second leading cause in developing countries. Colorectal cancer (CRC) is the third most common cause of cancer-related deaths worldwide. Risk factors for CRC include obesity, a diet low in fruits and vegetables, physical inactivity, and smoking. CRC has a poor prognosis, and there is a critical need for new diagnostic and prognostic biomarkers to reduce related deaths. Recently, studies have focused more on molecular testing to guide targeted treatments for CRC patients. The most crucial feature of activated immune cells is the production and release of growth factors and cytokines that modulate the inflammatory conditions in tumor tissues. The cytokine network is valuable for the prognosis and pathogenesis of colorectal cancer as they can aid in the cost-effective and non-invasive detection of cancer. A large number of interleukins (IL) released by the immune system at various stages of CRC can act as "biomarkers". They play diverse functions in colorectal cancer, and include IL-4, IL-6, IL-8, IL-11, IL-17A, IL-22, IL-23, IL-33, TNF, TGF-β, and vascular endothelial growth factor (VEGF), which are pro-tumorigenic genes. However, there are an inadequate number of studies in this area considering its correlation with cytokine profiles that are clinically useful in diagnosing cancer. A better understanding of cytokine levels to establish diagnostic pathways entails an understanding of cytokine interactions and the regulation of their various biochemical signaling pathways in healthy individuals. This review provides a comprehensive summary of some interleukins as immunological biomarkers of CRC.

SMAD4 rs10502913 is Significantly Associated with Chronic Obstructive Pulmonary Disease in a Chinese Han Population: A Case-Control Study

Background

COPD is a respiratory disease caused by a combination of genetic and environmental factors. Polymorphism, as a genetic factor, can affect the susceptibility of the disease of COPD. In this study, we assessed the relationship between the polymorphisms of three genes and COPD risk in a Chinese Han population.

Patients and Methods

A total of 376 patients diagnosed with COPD and 284 control subjects were enrolled in this study. Multivariate logistic regression analysis was used to analyze the association between three polymorphisms (SMAD4 rs10502913, IL-4 rs2070874, HSPA1L rs2227956) and COPD susceptibility.

Results

The SMAD4 rs10502913 GG and AG genotype significantly increased COPD risk (adjusted OR = 2.235, 95% CI 1.198–4.104; adjusted OR = 2.218, 95% CI 1.204–4.151, respectively) compared with the AA genotype. In the stratification analyses, the GG genotype significantly increased the risk of COPD in subjects aged 60 and over (adjusted OR = 2.519, 95% CI 1.266–5.015) and with a smoking history of less than 30 years (p=0.009; adjusted OR = 3.751; 95% CI 1.398–10.062). This increased risk was more pronounced in the group of GOLD I and GOLD II (adjusted OR = 3.628, 95% CI 1.022–12.885; adjusted OR = 2.394, 95% CI 1.004–5.710, respectively). In addition, AG genotype was associated with an increased COPD risk in subjects aged 60 and over (adjusted OR = 2.599, 95% CI 1.304–5.176) and in smokers (p=0.021; adjusted OR = 2.269; 95% CI 1.132–4.548). This increased risk was more obvious in the group of GOLD III COPD (p=0.047; adjusted OR = 2.532; 95% CI 1.012–6.336).

Conclusion

Our present study indicated that the genotype GG and AG of SMAD4 rs10502913 are associated with an increased risk of COPD in a Chinese Han population. Further validation studies with large-scale populations are needed to confirm our findings.

Associations of IL-4, IL-4R, IL-17A, and IL-17F Polymorphisms with Colorectal Cancer Risk: A Meta-Analysis, Meta-Regression, and Trial Sequential Analysis

Both interleukin (IL)-4 and IL-17 polymorphisms may be involved in the pathogenesis and progression of colorectal cancer (CRC). Herein, we designed a meta-analysis to assess the associations between IL-4, IL-4R, IL-17A, and IL-17F polymorphisms and CRC risk. Scopus, Web of Science, Cochrane Library, and PubMed databases were searched to retrieve articles published until October 21, 2021. We used crude odds ratio (OR) and 95% confidence interval assessing the association of the polymorphisms and CRC risk in 5 genetic models. Trial sequential analysis for the primary analyses was used to control random errors. Twenty-three studies (8: IL-4 rs2243250, 4: IL-4R rs1801275, 5: IL-17A rs2275913, and 6: IL-17F rs763780) were involved in the meta-analysis. The pooled OR (P-value) for the association between IL-4 rs2243250 polymorphism and the CRC risk was 1.11 (0.08), 1.27 (0.12), 1.07 (0.37), 1.09 (0.17), and 1.22 (0.12), for IL-4R rs1801275 polymorphism was 0.71 (0.18), 1.05 (0.76), 0.86 (0.37), 0.87 (0.41), and 0.69 (0.39), for IL-17A rs2275913 polymorphism was 1.83 (0.0003), 1.73 (0.06), 1.47 (<0.001), 1.61 (0.001), and 1.42 (0.15), and for IL-17F rs763780 polymorphism was 1.07 (0.48), 5.33 (0.02), 1.08 (0.49), 1.08 (0.47), and 8.42 (0.002) in allelic, homozygous, heterozygous, recessive, and dominant models, respectively. The G allele and GA genotype of IL-17A rs2275913 polymorphism and the CC genotype of IL-17F rs763780 polymorphism had an elevated risk in CRC cases. The ethnicity and genotyping method, sample size, control, and publication year were effective factors on the pooled results.

IL13Pred: A method for predicting immunoregulatory cytokine IL-13 inducing peptides

BACKGROUND

Interleukin 13 (IL-13) is an immunoregulatory cytokine, primarily released by activated T-helper 2 cells. IL-13 induces the pathogenesis of many allergic diseases, such as airway hyperresponsiveness, glycoprotein hypersecretion, and goblet cell hyperplasia. In addition, IL-13 inhibits tumor immunosurveillance, leading to carcinogenesis. Since elevated IL-13 serum levels are severe in COVID-19 patients, predicting IL-13 inducing peptides or regions in a protein is vital to designing safe protein therapeutics particularly immunotherapeutic.

OBJECTIVE

The present study describes a method to develop, predict, design, and scan IL-13 inducing peptides.

METHODS

The dataset experimentally validated 313 IL-13 inducing peptides, and 2908 non-inducing homo-sapiens peptides extracted from the immune epitope database (IEDB). A total of 95 key features using the linear support vector classifier with the L1 penalty (SVC-L1) technique was extracted from the originally generated 9165 features using Pfeature. These key features were ranked based on their prediction ability, and the top 10 features were used to build machine learning prediction models. Various machine learning techniques were deployed to develop models for predicting IL-13 inducing peptides. These models were trained, tested, and evaluated using five-fold cross-validation techniques; the best model was evaluated on an independent dataset.

RESULTS

Our best model based on XGBoost achieves a maximum AUC of 0.83 and 0.80 on the training and independent dataset, respectively. Our analysis indicates that certain SARS-COV2 variants are more prone to induce IL-13 in COVID-19 patients.

CONCLUSION

The best performing model was incorporated in web-server and standalone package named 'IL-13Pred' for precise prediction of IL-13 inducing peptides. For large dataset analysis standalone package of IL-13Pred is available at (https://webs.iiitd.edu.in/raghava/il13pred/) webserver and over GitHub link: https://github.com/raghavagps/il13pred.

Effect of genotype on the disease course in idiopathic pulmonary fibrosis despite antifibrotic treatment

A genetic predisposition has been identified in 30% of idiopathic pulmonary fibrosis (IPF) cases. Although it is highly probable that the genotype affects the disease susceptibility and course in almost all patients, the specific genotype goes undetected. The aim of the present study was to explore the effects of variants of the genes encoding interleukin-4 (IL-4), mucin 5B (MUC5B), toll interacting protein (TOLLIP), surfactant protein A (SFPTA), transforming growth factor-β (TGF-β) and transporters associated with antigen processing (TAP1 and TAP2) on the course of IPF. A total of 50 patients with IPF were enrolled, and variants of these genes were assessed. Lung function at the time of diagnosis and after 6, 12 and 18 months, and the number of acute exacerbations and deaths in each observation period were measured. ANOVA was used to test the association between gene polymorphisms and the decrease in lung function. There was no significant effect of the gene polymorphisms on the outcomes of patients up to 6 months during the observation period. After 12 months, an effect of an IL-4 single nucleotide polymorphism (SNP) (rs 2070874) on patient outcomes was observed [relative risk (RR) for T allele: 5.6; 95% confidence interval (CI), 0.79-39.0; P=0.053]. The RR of progression in patients with the IL-4 SNP (rs 2243250) and the CT and TT genotypes was 4.3 (95% CI, 1.1-17.5; P=0.046). A total of 18 months after the diagnosis of IPF, an effect of the TOLLIP polymorphism on patient outcome was detected (rs 111521887; risk allele GC; RR: 7.2; 95% CI, 0.97-53.6; P=0.052). Thus, IL-4 and TOLLIP gene polymorphisms may represent disease course-modifying factors, but not drivers of IPF.

The correlation between IL-4 polymorphisms and colorectal cancer risk in a population in Northwest China

Our aim was to investigate whether polymorphisms in the interleukin-4 (IL-4) gene are associated with the risk of colorectal cancer (CRC) in a Chinese Han population. Six single-nucleotide polymorphisms (SNPs) in the IL-4 were genotyped by Agena MassARRAY in 248 CRC patients and 463 healthy controls. The association of IL-4 polymorphisms with CRC risk was assessed by genetic models, linkage disequilibrium, and haplotype analyses. The results suggested that the CC genotype of rs2243250 confers a lower risk of CRC in the recessive model [odds ratio (OR) =  0.42, 95% confidence interval (CI): 0.19-0.92, P = 0.020]. Similarly, rs2227284 GG was associated with a reduced risk of CRC in the codominant (OR = 0.18, 95% CI: 0.04-0.82, P = 0.027) and recessive (OR = 0.19, 95% CI: 0.04-0.83, P = 0.008) models adjusted for age. Our findings suggested that rs2243250 and rs2227284 in IL-4 are associated significantly with reduced CRC risk, which may facilitate the identification of CRC patients in Chinese populations.

Associations of interleukin-4 and interleukin-4 receptor loci with esophageal squamous cell carcinoma susceptibility

Some functional polymorphisms in immune-regulating genes could affect the development of esophageal squamous cell carcinoma (ESCC). We enrolled 721 patients with ESCC and 1,208 healthy controls to explore the roles of rs2227282 (C > G) and rs2243283 (C > G) loci in the interleukin-4 (IL4) gene and rs1801275 loci in the interleukin-4 receptor (IL4R) gene for the occurrence of ESCC. As for IL4, the single nucleotide polymorphism rs2227282 (C > G) conferred an overall decreased risk for ESCC (adjusted P = 0.005, power = 0.816 in GG vs. CC genetic models). A stratification analysis of IL4 rs2227282 (C > G) and rs2243283 (C > G) and IL4R rs1801275 (A > G) loci with the ESCC risk revealed that the IL4 rs2243283 (C > G) polymorphism was a protective factor for the susceptibility to ESCC in some subgroups (women: power = 0.932 in CG vs. CC and 0.956 in CG/GG vs. CC; subjects aged ≥63 years: power = 0.844 in CG/GG vs. CC; never-smokers: power = 0.893 in CG vs. CC and 0.882 in CG/GG vs. CC; never-drinkers: power = 0.904 in CG vs. CC and 0.862 in CG/GG vs. CC). We also investigated the association of IL4 rs2227282 and rs2243283 and IL4R rs1801275 loci with the lymph node status. However, a null relationship was found. In conclusion, the present study highlighted that IL4 rs2227282 (C > G) and rs2243283 (C > G) loci are protective factors for the occurrence of ESCC.

Investigation of IL-4, IL-10, and HVEM polymorphisms with esophageal squamous cell carcinoma: a case-control study involving 1929 participants

It is believed that an individual’s hereditary factors may be involved in the development of esophageal cancer (EC). The present study recruited 721 esophageal squamous cell carcinoma (ESCC) cases and 1208 controls and explored the roles of single nucleotide polymorphisms (SNPs) in the interleukin-4 (IL-4), IL-10, and herpesvirus entry mediator (HVEM) genes in contributing to ESCC risk. IL-4, IL-10, and HVEM SNPs were analyzed by employing an SNPscan method. After adjustment for body mass index (BMI), smoking, drinking, age and gender, we identified that the rs2070874 T>C locus in IL-4 gene decreased the risk of ESCC (CC vs. TT: P=0.008; CC vs. TT/TC: P=0.010). After a stratified analysis, we suggested that the IL-4 rs2070874 T>C variants might be a protective factor for ESCC in male, ≥63 years old, never smoking, drinking and BMI < 24 kg/m² subgroups. In addition, we identified that the rs2243263 G>C polymorphism in IL-4 gene was a risk factor for ESCC development in the BMI ≥ 24 kg/m² subgroup (GC vs. GG: P=0.030 and GC/CC vs. GG: P=0.018). We identified an association of the IL-4 rs2070874 T>C SNP with the decreased susceptibility of ESCC in stage I/II subgroup. Finally, we found an association of the IL-10 rs1800872 T>G SNP with a worse differentiation (TG vs. TT: P=0.048 and GG/TG vs. TT: P=0.032). In conclusion, the findings indicate a potential importance of IL-4 rs2070874 T>C, IL-4 rs2243263 G>C and IL-10 rs1800872 T>G SNPs in the development of ESCC.

A Novel Nine Apoptosis-Related Genes Signature Predicting Overall Survival for Kidney Renal Clear Cell Carcinoma and its Associations with Immune Infiltration

Background: This study was designed to establish a sensitive prognostic model based on apoptosis-related genes to predict overall survival (OS) in patients with clear cell renal cell carcinoma (ccRCC). Methods: Obtaining the expression of apoptosis-related genes and associated clinical parameters from online datasets (The Cancer Genome Atlas, TCGA), their biological function analyses were performed through differently expressed genes. By means of LASSO, unadjusted and adjusted Cox regression analyses, this predictive signature was constructed and validated by internal and external databases (both TCGA and ArrayExpress). Results: A total of nine apoptosis-related genes (SLC27A2, TNFAIP2, IFI44, CSF2, IL4, MDK, DOCK8, WNT5A, APP) were ultimately screened as associated hub genes and utilized to construct a prognosis model. Then our constructed riskScore model significantly passed the validation in both the internal and external datasets of OS (all p < 0.05) and verified their expressions by qRT-PCR. Moreover, we conducted the Receiver Operating Characteristic (ROC), finding the area under the ROC curves (AUCs) were all above 0.70 which indicated that riskScore was a stable independent prognostic factor (p < 0.05). Furthermore, prognostic nomograms were established to figure out the relationship between 1-, 3- and 5-year OS and individual parameters for ccRCC patients. Additionally, survival analyses indicated that our riskScore worked well in predicting OS in subgroups of age, gender, grade, stage, T, M, N0, White (all p < 0.05), except for African, Asian and N1 (p > 0.05). We also explored its association with immune infiltration and applied cMap database to seek out highly correlated small molecule drugs. Conclusion: Our study successfully constructed a prognostic model containing nine hub apoptosis-related genes for ccRCC, helping clinicians predict patients' OS and making the prognostic assessment more standardized. Future prospective studies are required to validate our findings.

Possible Roles of Interleukin-4 and -13 and Their Receptors in Gastric and Colon Cancer

Interleukin (IL)-4 and -13 are structurally and functionally related cytokines sharing common receptor subunits. They regulate immune responses and, moreover, are involved in the pathogenesis of a variety of human neoplasms. Three different receptors have been described for IL-4, but only IL-4 receptor type II (IL-4Rα/IL-13Rα1) is expressed in solid tumors. While IL-13 can also bind to three different receptors, IL-13 receptor type I (IL-4Rα/IL-13Rα1/IL-13Rα2) and type II (IL-4Rα/IL-13Rα1) are expressed in solid tumors. After receptor binding, IL-4 and IL-13 can mediate tumor cell proliferation, survival, and metastasis in gastric or colon cancer. This review summarizes the results about the role of IL-4/IL-13 and their receptors in gastric and colon cancer.

Interleukin4Rα (IL4Rα) and IL13Rα1 Are Associated with the Progress of Renal Cell Carcinoma through Janus Kinase 2 (JAK2)/Forkhead Box O3 (FOXO3) Pathways

Specific kinds of interleukin (IL) receptors are known to mediate lymphocyte proliferation and survival. However, recent reports have suggested that the high expression of IL4Rα and IL13Rα1 in tumor tissue might be associated with tumorigenesis in several kinds of tumor. We found that a significant association between mRNA level of IL4Rα or IL13Rα1 and the poor prognosis of renal cell carcinoma (RCC) from the public database (http://www.oncolnc.org/). Then, we evaluated the clinicopathological significance of the immunohistochemical expression of IL4Rα and IL13Rα1 in 199 clear cell RCC (CCRCC) patients. The individual and co-expression patterns of IL4Rα and IL13Rα1 were significantly associated with cancer-specific survival (CSS) and relapse-free survival (RFS) in univariate analysis. Multivariate analysis indicated IL4Rα-positivity and co-expression of IL4Rα and IL13Rα1 as the independent indicators of shorter CSS and RFS of CCRCC patients. For the in vitro evaluation of the oncogenic role of IL4Rα and IL13Rα1 in RCC, we knock-downed IL4Rα or IL13Rα1 and observed that the cell proliferation rate was decreased, and the apoptosis rate was increased in A498 and ACHN cells. Furthermore, we examined the possible role of Janus kinase 2 (JAK2), well-known down-stream tyrosine kinase under the heterodimeric receptor complex of IL4Rα and IL13Rα1. Interestingly, JAK2 interacted with Forkhead box O3 (FOXO3) to cause tyrosine-phosphorylation of FOXO3. Silencing IL4Rα or JAK2 in A498 and ACHN cells reduced the interaction between JAK2 and FOXO3. Moreover, pharmacological inhibition of JAK2 induced the nuclear localization of FOXO3, leading to increase apoptosis and decrease cell proliferation rate in A498 and ACHN cells. Taken together, these results suggest that IL4Rα and IL13Rα1 might be involved in the progression of RCC through JAK2/FOXO3 pathway, and their expression might be used as the novel prognostic factor and therapeutic target for RCC patients.

IL-4/IL-4R and IL-6/IL-6R genetic variations and gastric cancer risk in the Chinese population

The IL-4/IL-4R and IL-6/IL-6R signaling pathways are involved in immune response and play roles in gastric carcinogenesis. To investigate the association between IL-4/IL-4R and IL-6/IL-6R genetic variations and gastric cancer risk, and their prognostic values, we performed a case-control study. The genotypes of the genetic variations were detected using a Mass-array platform. The Helicobacter pylori infection status was determined using a commercial H. pylori immunogold testing kit. We found that the IL-6 rs1800796 G allele was associated with an increased risk of gastric cancer (GG vs. CC: OR_adjusted = 2.20, 95% CI = 1.33-3.63; GG/CG vs. CC: OR_adjusted = 1.41, 95% CI = 1.09-1.82). The stratified analysis showed that rs1800796 G allele carriers (GG/CG) were associated with an increased risk of gastric cancer in the following subgroups: age >64 years old (OR_adjusted = 1.67, 95% CI = 1.17-2.39), female (OR_adjusted = 1.82, 95% CI = 1.09-3.05), positive for H. pylori infection (OR_adjusted = 1.54, 95% CI = 1.07-2.22), non-cardiac gastric cancer (OR_adjusted = 1.53, 95% CI = 1.15-2.04), stage T3-T4 tumor (OR_adjusted = 1.41, 95% CI = 1.06-1.88), and gastric cancer with median to high differentiation (OR_adjusted = 1.45, 95% CI = 1.08-1.96). None of the genetic variations were associated with overall survival. In short, we concluded that the IL-6 rs1800796 GG genotype is a risk factor for gastric cancer and that rs1800796 G allele carriers have an increased risk of gastric cancer; this association was stronger in individuals that were >64 years old, female, or positive for H. pylori infection. None of the genetic variations were associated with gastric cancer prognosis.

Circulating inflammation-related markers and advanced gastric premalignant lesions

BACKGROUND AND AIM

Chronic Helicobacter pylori infection causes gastric mucosal inflammation as an important antecedent of gastric cancer. We aimed to evaluate associations of blood markers of inflammation with gastric intestinal metaplasia and dysplasia in H. pylori-infected individuals.

METHODS

We compared pre-treatment serum levels of immune-related and inflammation-related markers between 99 individuals with intestinal metaplasia or dysplasia and 75 control individuals with non-atrophic gastritis within an H. pylori eradication trial in Mexico. Serum levels of 28 markers measured with Luminex bead-based assays were categorized in tertiles as low (T1), middle (T2), and high (T3). Logistic regression models were used to calculate age-adjusted and sex-adjusted odds ratios and 95% confidence intervals. All statistical tests were two-sided, and significance values were adjusted for multiple comparisons using false discovery rate methods.

RESULTS

Five markers were nominally associated (P_trend  < 0.05) with the presence of advanced premalignant gastric lesions. Adjusted odds ratios (95% confidence interval) of T2 and T3 versus T1 were 4.09 (1.65-10.17) and 3.08 (1.23-7.68) for CCL3/MIP1A, 3.21 (1.33-7.75) and 2.69 (1.10-6.57) for CCL20/MIP3A levels, 1.79 (0.77-4.18) and 2.39 (1.02-5.60) for IL-1β, 1.34 (0.56-3.19) and 3.02 (1.29-7.12) for IL-4, and 1.07 (0.44-2.59) and 3.07 (1.32-7.14) for IL-5, respectively. Two (IL-4 and IL-5) of the five markers had false discovery rate adjusted P_trend  < 0.2.

CONCLUSIONS

Our results suggest that certain Th2 and other cytokines may have a role in promoting carcinogenesis in the setting of H. pylori infection. Additional research is needed to replicate these findings, extend to pre-diagnostic samples, and elucidate the underlying mechanisms.

Genetic Association between Interleukin-4 Receptor Polymorphisms and Cancer Susceptibility: A Meta-Analysis Based on 53 Case-Control Studies

Polymorphisms in interleukin-4 receptor (IL-4R) gene have been reported susceptible to a variety of cancer types, nevertheless, data from these publications remained inconsistent and controversial. We further performed a comprehensive meta-analysis to present a precise estimation of its relationship. Extensive retrieve was performed in PubMed, Google Scholar and Web of Science up to May 25, 2018. Odds ratios (ORs) and 95% confidence intervals (CIs) were conducted to evaluate the overall strength of the associations in five genetic models, as well as in subgroup analyses, stratified by ethnicity, cancer type or source of control. Q-test, Egger's test and Begg's funnel plot were applied to evaluate the heterogeneity and publication bias. In-silico analysis was managed to demonstrate the relationship of IL-4R expression correlated with cancer tissues. Finally, 31 publications including 53 case-control studies were enrolled, with 24,452 cases and 24,971 controls. After a comprehensive analysis, no significant evidence was revealed for the association between four IL-4R polymorphisms (rs1801275, rs1805010, rs1805015, rs2057768) and cancer susceptibility in the overall population, as well as the subgroup analysis stratified by ethnicity, cancer type, the genotyping method or the source of control. To sum up, no evidence was identified between IL-4R polymorphisms and overall cancer susceptibility. Further well-designed studies with large sample sizes will be continued on this issue of interest.

Polymorphism rs4787951 in IL-4R contributes to the increased risk of renal cell carcinoma in a Chinese population

OBJECTIVE

Interleukins are important molecules involved in tumor formation. In this study, the association between renal cell carcinoma (RCC) risk and single nucleotide polymorphisms (SNPs) on IL-4/IL-13/IL-4R was assessed.

METHODS

We recruited 620/623 cases/controls and conducted a case-control study. Five tagSNPs (i.e., IL-4R rs8832, IL-4R rs4787951, IL-13 rs1881457, IL-13 rs2066960 and IL-13 rs2069744) were selected. Odds ratios (ORs) with their 95% confidence intervals (CIs) were obtained to appraise the association between SNPs and RCC susceptibility. Luciferase report assay and EMSA were conducted to investigate whether SNPs could affect binding affinity of transcription factors to target genes.

RESULTS

IL-4R rs4787951T>C was significantly associated with RCC susceptibility. Individuals carrying CC genotypes had a significant increment in RCC risk compared with TT genotype carriers (adjusted OR = 1.57, 95% CI = 1.07-2.28, P = 0.020). By stratified analyses, more pronounced association was found in the female, diabetic or without smoking, drinking and hypertension group. Besides, SNP rs4787951 could influence the binding affinity of IL-4R to transcription factors. Sequence surrounding allele T was prone to bind transcription factor NFATc.

CONCLUSIONS

This study revealed that IL-4R rs4787951T>C was associated with susceptibility of RCC and could be a predictive biomarker for RCC risk.

Role of polymorphisms in genes that encode cytokines and Helicobacter pylori virulence factors in gastric carcinogenesis

The Helicobacter pylori (H. pylori) infection is a determinant factor in gastric cancer (GC) development. However, the infection outcomes are variable and depend on both host and bacterial characteristics. Some host cytokines such as interleukin (IL)-1β, IL-1Ra, IL-8, IL-10 and tumor necrosis factor-α play important roles in the host immune system response to the pathogen, in the development of gastric mucosal lesions and in cell malignant transformation. Therefore, these host factors are crucial in neoplastic processes. Certain polymorphisms in genes that encode these cytokines have been associated with an increased risk of GC. On the other hand, various virulence factors found in distinct H. pylori bacterial strains, including cytotoxin-associated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and blood group antigen binding adhesin, have been associated with the pathogenesis of different gastric diseases. The virulent factors mentioned above allow the successful infection by the bacterium and play crucial roles in gastric mucosa lesions, including malignant transformation. Moreover, the role of host polymorphisms and bacterial virulence factors in gastric carcinogenesis seems to vary among different countries and populations. The identification of host and bacterium factors that are associated with an increased risk of GC development may be useful in determining the prognosis of infection in patients, what could help in clinical decision-making and in providing of an optimized clinical approach.

TGFβ C-509T, TGFβ T869C, XRCC1 Arg194Trp, IKBα C642T, IL4 C-590T Genetic polymorphisms combined with socio-economic, lifestyle, diet factors and gastric cancer risk: A case control study in South Indian population

BACKGROUND

Gastric cancer is worldwide the third major cause of cancer related death. Risk factors for gastric cancer includes Helicobacter pylori infection, gastric ulcer, less hygienic condition, use of tobacco, alcohol consumption, use of salted, smoked food, genetic alterations etc. In order to identify the risk factors associated with gastric cancer in South Indian population a case-control study involving 200 proven gastric cancer cases and 400 controls was conducted.

METHODS

A structured questionnaire was used to interview all the subjects who participated in our study. Genotyping assay was performed using Taqman allelic discrimination assay for 5 Single Nucleotide Polymorphisms (SNPs)-TGFβ C-509T, TGFβ T869C, XRCC1 Arg194Trp, IkBα C642T and IL4C-590T.

RESULTS

Odds Ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Statistical analysis on socio-economic factors, lifestyle factors had showed that subjects from low socio economic status, use of tobacco and consumption of non-vegetarian food had increased risk of developing gastric cancer. Multi-factorial analysis for the SNPs adjusting for the risk factors obtained in this study showed that TGFΒ C-509T TT genotypes had four fold increased risk of gastric cancer (OR = 4.11, CI = 1.02-16.56) and TGFβ T869C CC genotype had a decreased risk of gastric cancer (OR = 0.21, CI = 0.05-0.85).

CONCLUSION

Economic status, tobacco use and food habits play a significant role in gastric cancer development. TT genotype for TGFβ C-509T had an increased risk and CC genotype for TGFβ T869C had a decreased risk of gastric cancer in south Indian population after adjusting for socio-economic factors and lifestyle factors.

PKN2 in colon cancer cells inhibits M2 phenotype polarization of tumor-associated macrophages via regulating DUSP6-Erk1/2 pathway

BACKGROUND

Protein kinase N2 (PKN2) is a PKC-related serine/threonine-protein kinase. PKN2 is required for tumor cell migration, invasion and apoptosis. However, the functional role of PKN2 in regulating tumor associated macrophages (TAMs) polarization in colon cancer has never been reported.

METHODS

PKN2 expression in human colon cancer tissues was examined with immunohistochemistry (IHC). M1/M2 macrophage signatures were evaluated by RT-PCR, IHC and flow cytometry. The effects of PKN2 on tumor growth and TAM polarization were investigated both in vitro and in vivo. PKN2 targeted cytokines/pathway were analyzed by gene expression analysis and further confirmed by PCR, luciferase assay or western blot. Correlations between PKN2 and transcriptional factors for IL4 and IL10 were confirmed by ChIP-qPCR. The catalytic activities of PKN2 and DUSP6 were determined by kinase activity assay. Interactions between PKN2 and DUSP6 were confirmed by Co-IP.

RESULTS

The expression of PKN2 in colon cancer cells predicted a favorable prognosis and was associated with low M2 macrophage content in human colon cancer tissues. PKN2 inhibited tumor growth in mice xenograft model and inhibited M2 phenotype polarization both in vitro and in vivo. Mechanistically, PKN2 suppresses the expression of IL4 and IL10 from colon cancer cells by inhibiting Erk1/2 phosphorylation, which is required for phosphorylation and binding of CREB and Elk-1 to the promoters of IL4 and IL10. DUSP6, which is phosphorylated and activated through direct association with PKN2, suppresses Erk1/2 activation.

CONCLUSIONS

The expression of PKN2 in colon cancer cells suppresses tumor associated M2 macrophage polarization and tumor growth. Targeting PKN2 signaling pathway may provide a potential therapeutic strategy for colon cancer.