Gly972Arg variant of insulin receptor substrate 1 gene and colorectal cancer risk in overweight/obese subjects

The rs2275738 variant of the adiponectin receptor 1 gene is associated with biopsy-proven nonalcoholic fatty liver disease

Aim: Nonalcoholic fatty liver disease (NAFLD) is a significant health issue worldwide. This study investigated the effect of the adiponectin receptor 1 gene (ADIPOR1) polymorphism on susceptibility to NAFLD.Methods: Data from 330 participants, including 165 biopsy-proven NAFLD patients and 165 healthy controls, were collected. The PCR-RFLP method was used to detect the genotypes of ADIPOR1 rs2275738 or T-106C variant.Results: The "CC" genotype of the ADIPOR1 rs2275738 polymorphism, compared with the "TT" genotype and the "C" allele, compared with the "T" allele, are markers of increased NAFLD susceptibility (p = 0.018; OR = 2.07, 95% CI = 1.43-2.01 and p = 0.041; OR = 1.52, 95% CI = 1.24-2.35, respectively).Conclusion: This research suggests, for the first time, that the ADIPOR1 rs2275738 "CC" genotype is associated with a 107% increased risk for biopsy-proven NAFLD.

Association of IRS1 gene Pro512Ala polymorphism with nonalcoholic fatty liver disease

Objective

This study was designed to investigate the possible effect of the insulin receptor substrate 1 (IRS1) gene rs1801276 polymorphism on the risk of nonalcoholic fatty liver disease (NAFLD).

Subjects and methods

The rs1801276 polymorphism was investigated in 127 controls and 123 biopsy-proven NAFLD patients using PCR-RFLP.

Results

No deviation from Hardy-Weinberg equilibrium was discovered for the rs1801276 variant of IRS1 in either NAFLD patients or controls (P>0.05). The distribution of different rs1801276 genotypes and alleles showed significant variations between controls and NAFLD patients. In comparison to rs1801276 'CC' genotype, the "GG+GC" genotype occurred less frequently in NAFLD patients than in controls, which also persisted after adjustment for confounding factors (P = 0.041, OR = 0.60, 95% CI = 0.45-0.93). In comparison with the IRS1 rs1801276 "C" allele, the "G" allele was significantly less prevalent in NAFLD patients than in controls (P = 0.045, OR = 0.69, 95% CI = 0.58-0.91).

Conclusions

For the first time, we reported a significant association between the IRS1 rs1801276 polymorphism and biopsy-proven NAFLD. More studies are required to further elucidate the contribution of the IRS1 gene to NAFLD susceptibility.

The rs1862513 promoter variant of resistin gene influences susceptibility to nonalcoholic fatty liver disease

OBJECTIVES

Nonalcoholic fatty liver disease is the term used for a range of conditions in which fat builds up in the liver and exceeds 5% of hepatocytes without inordinate alcohol intake or other causes of lipid accumulation. Regarding the fact that insulin resistance and obesity play key roles in the pathogenesis of nonalcoholic fatty liver disease, as well as the connection between resistin and these metabolic diseases, the association between nonalcoholic fatty liver disease and a resistin gene (RETN) polymorphism was examined.

METHODS

In this genetic case-control association study, 150 biopsy-proven nonalcoholic fatty liver disease patients and 154 controls were enrolled and genotyped for the RETN rs1862513 (-420C>G) gene polymorphism using PCR-RFLP method.

RESULTS

The -420C>G genotype frequency distributions in both groups were consistent with Hardy-Weinberg equilibrium (HWE; p>0.05). The carriers of the RETN -420C>G "CC" genotype compared with the "GG" genotype occurred less frequently in the cases with nonalcoholic fatty liver disease than in the controls, and the difference remained significant even after adjustment for confounding factors (p=0.030; OR=0.47, 95%CI=0.36-0.93). Interestingly, the RETN -420C>G "C" allele was also associated with a decreased risk for nonalcoholic fatty liver disease too (p=0.042; OR=0.72, 95%CI=0.53-0.95).

CONCLUSION

We found for the first time an association between biopsy-proven nonalcoholic fatty liver disease and RETN -420C>G promoter polymorphism. The carriers of the RETN -420C>G "CC" genotype had a 53% decreased risk for nonalcoholic fatty liver disease. Our findings, however, need to be corroborated by further studies.

NAMPT gene rs2058539 variant is a risk factor for nonalcoholic fatty liver disease

OBJECTIVE

Nonalcoholic fatty liver disease is a chronic liver disease and a growing global epidemic. The aim of this study was to investigate the association between a visfatin gene (NAMPT) variant and nonalcoholic fatty liver disease, owing to the connection between this disease and insulin resistance, obesity, inflammation, and oxidative stress, and the role of visfatin in these metabolic disorders.

METHODS

In the present case-control study, we enrolled 312 genetically unrelated individuals, including 154 patients with biopsy-proven nonalcoholic fatty liver disease and 158 controls. The rs2058539 polymorphism of NAMPT gene was genotyped using the PCR-RFLP method.

RESULTS

Genotype and allele distributions of NAMPT gene rs2058539 polymorphism conformed to the Hardy-Weinberg equilibrium both in the case and control groups (p>0.05). The distribution of NAMPT rs2058539 genotypes and alleles differed significantly between the cases with nonalcoholic fatty liver disease and controls. The "CC" genotype of the NAMPT rs2058539 compared with "AA" genotype was associated with a 2.5-fold increased risk of nonalcoholic fatty liver disease after adjustment for confounding factors [p=0.034; odds ratio (OR)=2.52, 95% confidence interval (CI)=1.36-4.37]. Moreover, the NAMPT rs2058539 "C" allele was significantly overrepresented in the nonalcoholic fatty liver disease patients than controls (p=0.022; OR=1.77, 95%CI=1.14-2.31).

CONCLUSION

Our findings indicated for the first time that the NAMPT rs2058539 "CC" genotype is a marker of increased nonalcoholic fatty liver disease susceptibility; however, it needs to be supported by further investigations in other populations.

Insulin receptor substrate 2 gene Gly1057Asp polymorphism is a risk factor for nonalcoholic fatty liver disease

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD), which is an emerging global chronic liver disease, has a close association with insulin resistance. We aimed to determine whether the Gly1057Asp (rs1805097) polymorphism of the insulin receptor substrate 2 (IRS2) gene is associated with NAFLD.

METHODS

Using the polymerase chain reaction-restriction fragment length polymorphism method, 135 patients with biopsy-proven NAFLD and 135 controls underwent IRS2 genotype analysis.

RESULTS

Genotype and allele distributions of the IRS2 gene Gly1057Asp variant conformed to the Hardy-Weinberg equilibrium in both the case and control groups (P > .05). The Asp/Asp genotype of IRS2 gene Gly1057Asp polymorphism compared with Gly/Gly genotype was associated with a 2.1-fold increased risk for NAFLD after adjustment for confounding factors (P = .029; odds ratio = 2.10, 95% CI = 1.23-3.97).

CONCLUSION

Our findings revealed for the first time that the Gly1057Asp Asp/Asp genotype of the IRS2 gene is a marker of increased NAFLD susceptibility; however, studies in other populations are required to confirm the results.

A systematic review and meta-analysis for the association of the insulin-like growth factor1 pathway genetic polymorphisms with colorectal cancer susceptibility

Background

The receptors, ligands, and associated proteins of the insulin-like growth factor (IGF) family are involved in cancer development. The IGF1 receptor and its accompanying signaling cascade are a crucial growth-regulatory mechanism that plays an important role in colorectal cancer (CRC) proliferation and differentiation. IRS1 (Insulin receptor substrate-1), a major substrate for the IGF1R, is involved in cell growth and promotes tumorigenesis. There are shreds of evidence from prior research suggesting that IGF system polymorphisms may influence susceptibility to CRC. However, the findings in this area were contradictory. Accordingly, we carried out a systematic literature search to identify all case-control, cross-sectional, and cohort studies on the association between various polymorphisms across four IGF1 pathway genes (IGF1, IGF1R, IRS1, and IRS2) and the risk of CRC.

Methods

We performed a comprehensive search strategy in PubMed, Scopus, and Web of Science databases for articles available until Aug 30, 2022. A total of 26 eligible studies with IGF1/IGF1R, IRS1 and IRS2 polymorphisms; met the inclusion criteria. All case-control studies for IGF1 rs6214C>T, IRS1 rs1801278G>A, and IRS2 rs1805097G>A comprising 22,084 cases and 29,212 controls were included in the current meta-analysis. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate relationships between the polymorphisms and CRC susceptibility. All statistical analyses were performed using STATA software version 14.0.

Results

The meta-analysis of available data for rs6214C>T, rs1801278G>A, and rs1805097G>A showed a significant association between these polymorphisms and an increased CRC risk in some of the comparisons studied (rs6214C>T, pooled OR for CC = 0.43, 95% CI 0.21- 0.87, P = 0.019; rs1801278G>A, OR for GA = 0.74, 95% CI 0.58-0.94, P = 0.016; rs1805097G>A, OR for GA = 0.83, 95% CI 0.71-0.96, P = 0.013). Nevertheless, the meta-analysis did not include other genetic variations in IGF1, IGF1R, IRS1, and IRS2 due to heterogeneity and limited sample size.

Conclusions

This systematic review and meta-analysis provide evidence that genetic variants in IGF1 rs6214C>T, IRS1 rs1801278G>A, and IRS2 rs1805097G>A are associated with an increased risk of CRC. These findings may contribute to a better understanding of the complex genetic mechanisms involved in CRC development and could inform future research on prevention and treatment strategies for this disease.

RESISTIN GENE POLYMORPHISM AND NONALCOHOLIC FATTY LIVER DISEASE RISK

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease and one of the main global health issues in which liver fat surpasses 5% of hepatocytes without the secondary causes of lipid accumulation or excessive alcohol consumption. Owing to the link between NAFLD and insulin resistance (IR) and obesity and the role of resistin in theses metabolic disorders, we explored the possible association between resistin gene (RETN) variant and NAFLD.

METHODS

A total of 308 unrelated subjects, including 152 patients with biopsy-proven NAFLD and 156 controls were enrolled and genotyped for the RETN gene rs3745367 variant using PCR-RFLP method.

RESULTS

NAFLD patients had higher liver enzymes, systolic blood pressure (SBP), and diastolic blood pressure (DBP) than the controls (P<0.001). However, we observed no significant difference in genotype and allele frequencies between the cases with NAFLD and the controls for the RETN rs3745367 polymorphism either before or after adjustment for confounding factors including age, BMI, sex, smoking status, SBP, and DBP.

CONCLUSION

To our knowledge, this study is the first one that investigated the association between RETN gene rs3745367 variant and biopsy-proven NAFLD. Our findings do not support a role for this gene polymorphism in NAFLD risk in Iranian population; nonetheless, they need to be further investigated in other populations.

The Insulin-like Growth Factor System and Colorectal Cancer

Insulin-like growth factors (IGFs) are peptides which exert mitogenic, endocrine and cytokine activities. Together with their receptors, binding proteins and associated molecules, they participate in numerous pathophysiological processes, including cancer development. Colorectal cancer (CRC) is a disease with high incidence and mortality rates worldwide, whose etiology usually represents a combination of the environmental and genetic factors. IGFs are most often increased in CRC, enabling excessive autocrine/paracrine stimulation of the cell growth. Overexpression or increased activation/accessibility of IGF receptors is a coinciding step which transmits IGF-related signals. A number of molecules and biochemical mechanisms exert modulatory effects shaping the final outcome of the IGF-stimulated processes, frequently leading to neoplastic transformation in the case of irreparable disbalance. The IGF system and related molecules and pathways which participate in the development of CRC are the focus of this review.

The first combined meta‐analytic approach for elucidating the relationship of circulating resistin levels and RETN gene polymorphisms with colorectal and breast cancer

Background

Evidence suggests that circulating resistin levels are altered in colorectal cancer (CRC) and breast cancer (BC). Again, polymorphisms in resistin-encoding gene RETN have been evaluated in CRC and BC. However, there is a scarcity of data establishing the relationship of resistin and RETN polymorphisms (rs1862513 and rs3745367) with these cancers. This study aimed to analyze the relationship of resistin levels and RETN polymorphisms with CRC and BC in a combined meta-analytic approach.

Main body of the abstract

After a comprehensive online literature search, screening and eligibility check, 41 articles (31 with resistin level and 10 with RETN polymorphisms) were retrieved for meta-analyses. The mean difference (MD) of resistin was calculated and pooled to investigate the effect sizes with a 95% confidence interval (CI), and the connection of genetic polymorphisms was analyzed with an odds ratio (OR) and 95% CI. The analysis showed that resistin level is significantly higher in CRC (MD = 3.39) and BC (MD = 3.91) patients. Subgroup analysis in CRC showed significantly higher resistin in serum (MD = 4.61) and plasma (MD = 0.34), and in BC, a significantly elevated resistin level was reported in premenopausal (MD = 7.82) and postmenopausal (MD = 0.37) patients. Again, RETN rs1862513 showed a significantly strong association with CRC (codominant 1—OR 1.24, codominant 2—OR 1.31, dominant model—OR 1.25, and allele model—OR 1.16) and with BC (codominant 2—OR 1.51, codominant 3—OR 1.51, recessive model—OR 1.51, and allele model—OR 1.21). RETN rs3745367 did not show any association with these cancers.

Short conclusion

Overall, our analysis indicates that higher circulating resistin levels are associated with an elevated risk of CRC and premenopausal and postmenopausal BC. Besides, rs1862513 in RETN gene is significantly connected with both CRC and BC.

CIRCULATING GHRELIN LEVELS AND SUSCEPTIBILITY TO COLORECTAL CÂNCER

BACKGROUND AND OBJECTIVE

Considering the association between colorectal cancer (CRC) and both insulin resistance and obesity, and the prominent role of ghrelin in these metabolic disorders, we explored whether plasma levels of ghrelin were associated with CRC. Moreover, in the patients with CRC the possible correlations between ghrelin and insulin, insulin resistance, and body mass index (BMI) as an indicator of obesity were examined.

METHODS

A total of 170 subjects, including 82 cases with CRC and 88 controls were enrolled in this study. Plasma levels of ghrelin, insulin, and glucose were measured in all the subjects using ELISA and glucose oxidase methods. Furthermore, insulin resistance was assessed by calculating HOMA-IR index.

RESULTS

The cases with CRC had decreased ghrelin levels (P<0.001) and a higher HOMA-IR index (P<0.001) than controls. Interestingly, when CRC patients were stratified based on tumor site, lower ghrelin levels and a higher HOMA-IR index were observed in the patients with either colon or rectal cancer vs. controls too. Additionally, there were an age and BMI-independent negative correlation between ghrelin levels and HOMA-IR (r=-0.365, P<0.05), and an age-independent negative correlation between ghrelin levels and BMI (r=-0.335, P<0.05) in the rectal subgroup.

CONCLUSION

Our findings support a role for ghrelin in connection with insulin resistance and obesity in CRC susceptibility; however, it needs to be corroborated by further studies.

The effects of genetic variants related to insulin metabolism pathways and the interactions with lifestyles on colorectal cancer risk

OBJECTIVES

Genetic variants in metabolic signaling pathways may interact with lifestyle factors, such as dietary fatty acids, influencing postmenopausal colorectal cancer (CRC) risk, but these interrelated pathways are not fully understood.

METHODS

In this study, we examined 54 single-nucleotide polymorphisms (SNPs) in genes related to insulin-like growth factor-I/insulin traits and their signaling pathways and lifestyle factors in relation to postmenopausal CRC, using data from 6,539 postmenopausal women in the Women's Health Initiative Harmonized and Imputed Genome-Wide Association Studies. By employing a two-stage random survival forest analysis, we evaluated the SNPs and lifestyle factors by ranking them according to their predictive value and accuracy for CRC.

RESULTS

We identified four SNPs (IRS1 rs1801123, IRS1 rs1801278, AKT2 rs3730256, and AKT2 rs7247515) and two lifestyle factors (age and percentage calories from saturated fatty acids) as the top six most influential predictors for CRC risk. We further examined interactive effects of those factors on cancer risk. In the individual SNP analysis, no significant association was observed, but the combination of the four SNPs, age, and percentage calories from saturated fatty acid (≥11% per day) significantly increased the risk of CRC in a gene and lifestyle dose-dependent manner.

CONCLUSIONS

Our findings provide insight into gene-lifestyle interactions and will enable researchers to focus on individuals with risk genotypes to promote intervention strategies. Our study suggests the careful use of data on potential genetic targets in clinical trials for cancer prevention to reduce the risk for CRC in postmenopausal women.

Genetic and molecular origins of colorectal Cancer among the Iranians: an update

BACKGROUND

Colorectal cancer (CRC) is one the leading causes of cancer related deaths among Iranians. Despite the various progresses in new therapeutic methods, it has still a low rate of survival. This high ratio of mortality is mainly related to the late diagnosis, in which the patients refer for treatment in advanced stages of tumor. MAIN BODY: colorectal cancer progression is largely associated with molecular and genetic bases. Although Iran has a high ratio of CRC mortality, there is not an efficient genetic panel for detection and prognosis. Therefore, it is critical to introduce new diagnostic markers with ability to detect in early stages.

CONCLUSION

Present review summarizes all of the genetic and epigenetic factors which are reported in CRC until now among the Iranian patients to pave the way of incorporation of new ethnic specific markers into the clinical practice and development of new targeted therapeutic methods.

Association between rs1862513 and rs3745367 Genetic Polymorphisms of Resistin and Risk of Cancer: A Meta-Analysis

The present study aimed to assess any associations between resistin gene (RETN) polymorphisms and cancer susceptibility by conducting a meta-analysis. A comprehensive literature search was performed with PubMed, Web of Science, Scopus and Google Scholar for relevant studies published before April 2018. For the rs1862513 polymorphism, data from 9 studies covering 1,951 cancer patients and 2,295 healthy controls were included in this meta-analysis. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Our meta-analysis revealed that this RETN polymorphism significantly increased the risk of cancer in codominant (OR=1.23, 95% CI= 1.01-1.50, p=0.04, CG vs CC; and OR=1.25, 95% CI= 1.03-1.53, p=0.03, GG vs CC), dominant (OR=1.19, 95% CI= 1.05-1.35, p=0.006, CG+GG vs CC), and allele (OR=1.14, 95% CI= 1.00-1.30, p=0.04, G vs C) inheritance genetic models. Stratification analysis by cancer type revealed that the rs1862513 variant significantly increased the risk of colorectal and breast cancer, and that cancer overall in Caucasians (OR=1.22, 95% CI= 1.04-1.43, p=0.02, CG+GG vs CC; OR=1.18, 95% CI= 1.04-1.34, p=0.01, G vs C). The data revealed no correlation between the rs3745367 polymorphism and cancer risk. Further well-designed studies with larger sample sizes and different ethnicities are warranted to validate the present findings.

Correlation between resistin gene polymorphism and clinical aspects of lung cancer

Lung cancer is one of the most common cancers and is associated with a poor survival rate in the Chinese Han population. Analysis of genetic variants could lead to improvements in prognosis following lung cancer treatment. Resistin (RETN) is an important mediator of metabolic diseases and tumor progression. In this study, we explored the effects of RETN single nucleotide polymorphisms (SNPs) on the susceptibility and clinicopathological characteristics of patients with lung cancer. Four RETN SNPs (rs7408174, rs1862513, rs3745367, and rs3219175) were analyzed using TaqMan SNP genotyping in 371 patients with lung cancer and 451 cancer-free controls. The results showed that the RETN SNP rs3219175 with AG or at least 1 A allele was associated with a higher risk of lung cancer than wild-type (GG) carriers. Moreover, the RETN SNP rs3219175 with AG or AG + AA alleles was associated with a higher risk of distant metastasis than that in patients carrying GG alleles. We also used genotype-tissue expression datasets to compare the correlation of the RETN SNP rs3219175 in lung tissue and whole blood. In conclusion, our study demonstrated, for the first time, that RETN polymorphisms were correlated with lung cancer progression in the Chinese Han population.