Association between IRS-2 G1057D polymorphism and risk of gastric cancer

IL-4 and IL-13 Receptor Signaling From 4PS to Insulin Receptor Substrate 2: There and Back Again, a Historical View

In this historical perspective, written in honor of Dr. William E. Paul, we describe the initial discovery of one of the dominant substrates for tyrosine phosphorylation stimulated by IL-4. We further describe how this “IL-4-induced phosphorylated substrate” (4PS) was characterized as a member of the insulin receptor substrate (IRS) family of large adaptor proteins that link IL-4 and insulin receptors to activation of the phosphatidyl-inositol 3′ kinase pathway as well as other downstream signaling pathways. The relative contribution of the 4PS/IRS pathway to the early models of IL-4-induced proliferation and suppression of apoptosis are compared to our more recent understanding of the complex interplay between positive and negative regulatory pathways emanating from members of the IRS family that impact allergic responses.

A sequence polymorphism on 8q24 is associated with survival in hepatocellular carcinoma patients who received radiation therapy

There is a growing consensus that genetic variation in candidate genes can influence cancer progression and treatment effects. In this study, we genotyped the rs9642880 G > T polymorphism using DNA isolated from blood samples of 271 hepatocellular carcinoma (HCC) patients who received radiotherapy treatment. We found that patients who carried the GT or TT genotypes had significantly shorter median survival times (MSTs) compared to patients with the GG genotype (14.6 vs.21.4 months). The multivariate P value was 0.027, the hazard ratio (HR) was 1.38, and the 95% confidence interval was 1.04–1.84. Further analysis revealed that patients with the variant genotypes had an increased risk of poor tumour response to radiotherapy (P = 0.036 and 0.002 for stable disease and progressive disease, respectively) and higher incidence of multiple intrahepatic lesions (P = 0.026) and BCLC C stage (P = 0.027). Moreover, further stratified survival analyses revealed that at least radioresponse and BCLC stage contributed to the association between the rs9642880 G > T polymorphism and survival of HCC patients in this study (P value, 0.017 vs 0.053 for BCLC C stage vs B stage; 0.011 vs 0.531 for radioresponse SD + PD vs CR + PR). These results illustrate the potential association between rs9642880 G > T and survival in HCC patients who received radiotherapy treatment.

IRS-2 G1057D polymorphism in Turkish patients with colorectal cancer

Introduction

Gene polymorphisms have a broad range of analysis, but are of particular use in molecular medicine due to their potential in revealing the genetic tendency in diseases such as cancer, heart attack etc. These studies basically depend on mutations that can be detected by proper techniques. The genes coding the insulin receptor substrate (IRS) proteins are among the most widely analysed polymorphisms in various cancer types, in which a G1057D mutation is seen.

Aim

To determine the risk of colon cancer by analysing the IRS-2 gene polymorphism in Turkish patients.

Material and methods

A total of 161 newly diagnosed colorectal cancer patients were analysed and compared to 197 unrelated healthy controls. A polymerase chain reaction-based restriction fragment length polymorphism method was carried out.

Results

No differences were observed between the patient and control groups for both allele and genotype frequencies of the IRS-2 G1057D gene.

Conclusions

Our results demonstrated that IRS-2 G1057D polymorphism is not associated with colorectal cancer in the Turkish population. This research is a preliminary and original study in Turkish patients with colorectal cancer. It also provides population-level genetic data on IRS-2 in the Turkish population. Further studies should be performed on larger number of patients and controls for more reliable results about the genetic tendency in colorectal cancer in Turkey. The study is a collaborative work of different universities and scientists.

Impact of insulin-like growth factor 2, insulin-like growth factor receptor 2, insulin receptor substrate 2 genes polymorphisms on susceptibility and clinicopathological features of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death worldwide. Insulin-like growth factor-2 (IGF-2) is an important autocrine and paracrine growth factor which may induce cell proliferation and inhibit cell apoptosis leading to the transformation of normal cells into malignant cells. This study aimed to evaluate the possible roles of IGF-2, insulin-like growth factor-2 receptor (IGF-2R), and insulin receptor substrate (IRS)-2 genes polymorphisms in susceptibility and clinicopathological features of HCC in Egyptian population.

MATERIALS AND METHODS

Four hundred and twenty-six HCC patients and 334 controls were enrolled in the study. Polymorphisms of IGF-2+3580, IGF-2+3123, IGF-2R 1619, and IRS-2 1057 gene were detected using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Serum IGF-2 were determined using ELISA.

RESULTS

Serum IGF-2 levels were significantly lower in HCC patients than in healthy controls. IGF-2+3580 AA genotype, IGF-2+3123 GG genotype or G allele, IRS-2 1057 DD genotype and D allele were significantly associated with HCC risk. The combination of IGF-2+3580 AA homozygosity and IGF-2R 1619 GG homozygosity presented a significant protective effect against HCC (OR=0.16,95% CI=0. 08-0.34, P=0. 005). Serum IGF-2 concentrations were significantly increased in HCC patients with the IGF-2+3580 AA genotype. We also observed that increased alpha-fetoprotein (AFP), Child-Pugh grade, tumor size, and number of malignant lesions were accompanied by a significant increase of serum IGF-2 mean values of in HCC patients.

CONCLUSION

IGF-2, IGF-2R, and IRS-2 genes polymorphisms and their combinations are associated with risk of HCC.

Lack of association between insulin receptor substrate2 rs1805097 polymorphism and the risk of colorectal and breast cancer: a meta-analysis

BACKGROUND

Insulin receptor substrate-2 (IRS-2), a signaling adaptor protein, was involved in two cancer-related pathways (the phosphatidylinositol 3'-kinase (PI3K) and the extracellular signal-regulated kinase (ERK) pathways). Several studies have evaluated the association between IRS2 rs1805097 (G>A) polymorphisms and the risk of colorectal and breast cancer. However, the results were inconsistent.

METHODOLOGY/PRINCIPAL FINDINGS

A meta-analysis of seven published case-control studies (4 studies with 4798 cases and 5478 controls for colorectal cancer and 3 studies with 2108 cases and 2507 controls for breast cancer) were conducted to assess the strength of association using crude odd ratios (ORs) with 95% confidence intervals (CIs). For colorectal cancer, no obvious associations were found for all genetic models (homozygote comparison OR = 0.96, 95%CI 0.85-1.08, Pheterogeneity = 0.97; heterozygote comparison: OR = 0.91, 95%CI 0.73-1.13, Pheterogeneity<0.01; dominant model: OR = 0.92, 95%CI 0.80-1.06, Pheterogeneity = 0.05; recessive model: OR = 1.02, 95%CI 0.91-1.14, Pheterogeneity = 0.60). In the subgroup analysis by ethnicity, control source and consistency of frequency with Hardy-Weinberg equilibrium (HWE), still no significant associations were observed. For breast cancer, also no obvious associations were found for all genetic models (homozygote comparison: OR = 0.95, 95%CI 0.71-1.26, Pheterogeneity = 0.10; heterozygote comparison: OR = 1.00, 95%CI 0.89-1.14, Pheterogeneity = 0.71; dominant model: OR = 0.98, 95%CI 0.87-1.10, Pheterogeneity = 0.55; recessive model: OR = 0.95, 95%CI 0.72-1.25, Pheterogeneity = 0.07). We performed subgroup analyses by sample size and did not find an association.

CONCLUSIONS

This meta-analysis indicated that IRS2 rs1805097 polymorphism was not associated with colorectal and breast cancer risk.