Polymorphisms in RETN gene and susceptibility to colon cancer in Saudi patients

The pertinence of resistin gene single nucleotide polymorphism G > A and its expression in oral cancer

BACKGROUND/AIM

Oral cancer (OC) is the leading cause of fatalities in Pakistan among males due to inadequate oral hygiene and chewing habits. However, genetic susceptibility patterns also play a critical role in disease progression. Since the frequency of Resistin (RETN) SNP (Single nucleotide polymorphism) rs3219175 is unknown; there is a requirement for early diagnosis of the OC. Therefore, the current study aims to determine the frequency of targeted SNP and develop a safe, simple, and fast alternative technique for better treatment using a real-time PCR assay with HRM (high-resolution melting curve) analysis.

MATERIALS AND METHODS

A case-control study was conducted on 35 Oral squamous cell carcinomas (OSCC) diagnosed patients and 35 healthy individuals. HRM and RT-PCR results were analysed by the bioinformatics analyses.

RESULTS

The frequency of RETN SNP rs3219175 genotypes GG and GA in male patients was 16 (46 %) and 5 (14 %) respectively and in females 8 (23 %) and 6 (17 %) respectively. The chi-square test of independence consummated the assessment between males and females in both control and patients. The relation between these variables was significant (p < 0.05). The interaction network of String 8.3 demonstrates strong interactions at a high confidence score, which helps to characterize functional disorders that may be a causative factor for oral pathology. Reactome and KEGG data were acquired to rule out the pathway involvement of the targeted gene. MuPIT software was used to identify the 3D structure or RETN and their expected mutation effect.

CONCLUSION

This study provides baseline data regarding the frequency of RETN SNP rs3219175 among the Pakistani population. For further clarification of their stage in cancer emergence and growth, large-scale studies must be conducted. This study might be helpful in the precision medicine approach and provide better therapeutic for OSCC patients.

Clinical significance of RETN gene expression and rs3219175 G > a polymorphism in cancer

The inflammatory cytokine resistin, which is encoded by the RETN gene, plays a variety of roles in cancer. This study aimed to assess the relationship between RETN gene expression and cancer stage, survival prognosis, immune infiltration, and drug sensitivity, and whether the rs3219175 G > A polymorphism affected the expression of the RETN gene and cancer risk. The clinical significance of RETN gene expression and the rs3219175 polymorphism in cancer was analyzed by the GSCA platform, GTEx database and STATA software. The results showed that RETN gene expression was associated with the stage of thyroid carcinoma, survival prognosis and immune infiltration of certain cancers, and sensitivity to multiple drugs. The rs3219175 polymorphism could influence the expression of the RETN gene in a wide range of tissues. Furthermore, RETN gene rs3219175 polymorphism was significantly associated with cancer risk [GA vs. GG: OR = 2.27, 95%CI = 1.26-4.09; (GA + AA) vs. GG: OR = 2.23, 95%CI = 1.28-3.88; A vs. G: OR = 1.72, 95%CI = 1.15-2.58]. In conclusion, the current study suggested that resistin might serve as a prognostic marker and therapeutic target for certain cancers, and the rs3219175 polymorphism might be used as a marker for predicting cancer risk.

An Updated Review of Resistin and Colorectal Cancer

Resistin is one of the most important adipokines, and its role lies mainly in controlling insulin sensitivity and inflammation. However, over the last years, the study of resistin gained increased popularity since it was proved that there is a considerable relationship between high levels of resistin and obesity as well as obesity-induced diseases, including diabetes, cardiovascular disorders, and cancer. Regarding cancer risk, circulating resistin levels have been correlated with several types of cancer, including colorectal, breast, lung, endometrial, gastroesophageal, prostate, renal, and pancreatic cancer. Colorectal cancer is regarded as a multi-pathway disease. Several pathophysiological features seem to promote colorectal cancer (CRC) such as chronic inflammation, insulin resistance, and obesity. Even though the molecular mechanisms involved in CRC development remain rather vague, it is widely accepted that several biochemical factors promote CRC by releasing augmented pro-inflammatory cytokines, like IGF-I, insulin, sex-steroid hormones, and adipokines. A wide range of research studies has focused on evaluating the impact of circulating resistin levels on CRC risk and determining the efficacy of chemotherapy in CRC patients by measuring resistin levels. Moreover, significant outcomes have emerged regarding the association of specific single nucleotide polymorphisms (SNPs) in the resistin gene and CRC risk. The present study reviewed the role of circulating resistin levels in CRC development and shed light on specific resistin gene SNPs implicated in the disease's development. Finally, we analyzed the impact of resistin levels on the effectiveness of chemotherapy and further discussed whether resistin can be regarded as a valuable biomarker for CRC prognosis and treatment. Resistin is one of the most important adipokines, and its role lies mainly in controlling insulin sensitivity and inflammation. However, over the last years, the study of resistin gained increased popularity since it was proved that there is a considerable relationship between high levels of resistin and obesity as well as obesity-induced diseases, including diabetes, cardiovascular disorders, and cancer. This review discusses the aberrant expression of resistin and its receptors, its diverse downstream signaling, and its impact on tumor growth, metastasis, angiogenesis, and therapy resistance to support its clinical exploitation in biomarker and therapeutic development.

Molecular pathology of colorectal cancer: The Saudi situation in perspective

Colorectal cancer (CRC) is one of the most common cancers worldwide, and one of the most common causes of cancer deaths. In recent times, significant advancements have been made in elucidating the molecular alterations of the disease, and the results have been an improved understanding of CRC biology, as well as the discovery of biomarkers of diagnostic, prognostic, and therapeutic significance. In this review, an evaluation is carried out of the molecular pathology research of CRC emanating from Saudi Arabia. The verdict is that the data on the molecular alterations in CRC from Saudi patients is at best modest. This dearth of molecular pathology data is aptly reflected in the paucity of molecular markers recommended for testing by the Saudi National Cancer Centre guidelines for CRC management. Large scale multi-institutional and multiregional translational studies are required to generate molecular data that would inform diagnostic, prognostic, and risk-stratification guidelines for Saudi CRC patients.

Rs10204525 Polymorphism of the Programmed Death (PD-1) Gene Is Associated with Increased Risk in a Saudi Arabian Population with Colorectal Cancer

Checkpoint programmed death-1 (PD-1) has been identified as an immunosuppressive molecule implicated in the immune evasion of transformed cells. It is highly expressed in tumor cells in order to evade host immunosurveillance. In this study, we aimed to assess the association between single nucleotide polymorphisms (SNP) of PD-1 and the risk of colorectal cancer (CRC) in the Saudi population. For this case-control study, the TaqMan assay method was used for genotyping three SNPs in the PD-1 gene in 100 CRC patients and 100 healthy controls. Associations were estimated using odds ratios (ORs) and 95% confidence intervals (95% CIs) for multiple inheritance models (codominant, dominant, recessive, over-dominant, and log-additive). Moreover, PD-1 gene expression levels were evaluated using quantitative real-time PCR in colon cancer tissue and adjacent colon tissues. We found that the PD-1 rs10204525 A allele was associated with an increased risk of developing CRC (OR = 2.35; p = 0.00657). In addition, the PD-1 rs10204525 AA homozygote genotype was associated with a high risk of developing CRC in the codominant (OR = 21.65; p = 0.0014), recessive (OR = 10.97; p = 0.0015), and additive (OR = 1.98; p = 0.012) models. A weak protective effect was found for the rs2227981 GG genotype (OR = 2.52; p = 0.034), and no significant association was found between the rs2227982 and CRC. Haplotype analysis showed that the rs10204525, rs2227981, rs2227982 A-A-G haplotype was associated with a significantly increased risk of CRC (OR = 6.79; p =0.031).

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.

Roles of Adipokines in Digestive Diseases: Markers of Inflammation, Metabolic Alteration and Disease Progression

Adipose tissue is a highly dynamic endocrine tissue and constitutes a central node in the interorgan crosstalk network through adipokines, which cause pleiotropic effects, including the modulation of angiogenesis, metabolism, and inflammation. Specifically, digestive cancers grow anatomically near adipose tissue. During their interaction with cancer cells, adipocytes are reprogrammed into cancer-associated adipocytes and secrete adipokines to affect tumor cells. Moreover, the liver is the central metabolic hub. Adipose tissue and the liver cooperatively regulate whole-body energy homeostasis via adipokines. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, is currently considered a global epidemic and is related to low-grade systemic inflammation characterized by altered adipokine regulation. Obesity-related digestive diseases, including gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyps and cancer, non-alcoholic fatty liver disease, viral hepatitis-related diseases, cholelithiasis, gallbladder cancer, cholangiocarcinoma, pancreatic cancer, and diabetes, might cause specific alterations in adipokine profiles. These patterns and associated bases potentially contribute to the identification of prognostic biomarkers and therapeutic approaches for the associated digestive diseases. This review highlights important findings about altered adipokine profiles relevant to digestive diseases, including hepatic, pancreatic, gastrointestinal, and biliary tract diseases, with a perspective on clinical implications and mechanistic explorations.

Epidemiology of cancer in Saudi Arabia thru 2010-2019: a systematic review with constrained meta-analysis

Background

Cancer is emerging as a major global health-care system challenge with a growing burden worldwide. Due to the inconsistent cancer registry system in Saudi Arabia, the epidemiology of cancer is still dispersed in the country. Consequently, this review aimed to assemble the epidemiological metrics of cancer in Saudi Arabia in light of the available published data during the period from (2010–2019).

Methods

Published literature from Saudi Arabia relating to cancer incidence, prevalence, risk factors, and other epidemiological metrics were accessed through electronic search in Medline/PubMed, Cochrane, Scopus, Web of Knowledge, Google Scholar, and public database that meet the inclusion criteria. Relevant keywords were used during the electronic search about different types of cancers in Saudi Arabia. No filters were used during the electronic searches. Data were pooled and odds ratios (ORs) and 95% confidence interval (95%CI) were calculated. A random-effects meta-analysis was performed to assess the well-determined risk factors associated with different types of cancers.

Results

The most common cancers in Saudi Arabia are breast, colorectal, prostate, brain, lymphoma, kidney and thyroid outnumbering respectively. Their prevalence rates and OR (95%CI) as follow: breast cancer 53% and 0.93 (0.84–1.00); colon-rectal cancer (CRC) 50.9% and 1.2 (0.81–1.77); prostate cancer 42.6% and 3.2 (0.88–31.11); brain/Central Nervous System cancer 9.6% and 2.3 (0.01–4.2); Hodgkin and non-Hodgkin's lymphoma 9.2% and 3.02 (1.48–6.17); kidney cancer 4.6% and 2.05 (1.61–2.61), and thyroid cancer 12.9% and 6.77 (2.34–19.53).

Conclusion

Within the diverse cancers reported from Saudi Arabia, the epidemiology of some cancers magnitude 3-fold in the latest years. This increase might be attributed to the changing in the Saudi population lifestyle (adopting western model), lack of cancer awareness, lack of screening & early detection programs, social barriers toward cancer investigations. Obesity, genetics, sedentary lifestyle, tobacco use, viral infection, and iodine & Vit-D deficiency represent the apparent cancer risk factors in Saudi Arabia.

Impacts of RETN genetic polymorphism on breast cancer development

The adipokine resistin is linked with obesity, inflammation and various cancers, including breast cancer. This study sought to determine whether certain polymorphisms in the gene encoding resistin, RETN, increase the risk of breast cancer susceptibility. We analyzed levels of resistin expression in breast cancer tissue and samples from The Cancer Genome Atlas database. We also examined associations between four RETN single nucleotide polymorphisms (SNPs; rs3745367, rs7408174, rs1862513 and rs3219175) and breast cancer susceptibility in 515 patients with breast cancer and 541 healthy women without cancer. Compared with wild-type (GG) carriers, those carrying the AG genotype of the RETN SNP rs3219175 and those carrying at least one A allele in the SNP rs3219175 had a higher chance of developing breast cancer (adjusted odds ratio, AOR: 1.295, 95% confidence intervals, CI: 1.065-1.575 and 2.202, 1.701-2.243, respectively). When clinical aspects and the RETN SNP rs7408174 were examined in the breast cancer cohort, the CT genotype was linked to late-stage disease, while women with luminal A disease and at least one C allele were likely to progress to stage III/IV disease and to develop highly pathological grade III disease. Moreover, resistin-positive individuals were at greater risk than resistin-negative individuals for developing pathological grade III disease (OR: 5.020; 95% CI: 1.380-18.259). This study details risk associations between resistin and RETN SNPs in breast cancer susceptibility in Chinese Han women.

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.

Association of Resistin Gene Polymorphisms with Oral Squamous Cell Carcinoma Progression and Development

Oral squamous cell carcinoma (OSCC) accounts for over 90% of malignant neoplasms of the mouth. In Taiwan, OSCC is the fourth most common male cancer and the fourth leading cause of male cancer death. Resistin (RETN) is an adipokine that is associated with obesity, inflammation, and various cancers. Here, we examine the association between four single nucleotide polymorphisms (SNPs) of the RETN gene (rs3745367, rs7408174, rs1862513, and rs3219175) and OSCC susceptibility as well as clinical outcomes in 935 patients with OSCC and in 1200 cancer-free healthy controls. We found that, in 1465 smokers, RETN polymorphisms carriers with the betel-nut chewing habit had a 6.708–10.882-fold greater risk of having OSCC compared to RETN wild-type carriers without the betel-nut chewing habit. Patients with OSCC who had A/A homozygous of RETN rs3219175 polymorphism showed a high risk for an advanced tumor size (> T2), compared to those patients with G/G homozygotes. In addition, A/T/G/G haplotype significantly increased the risks for OSCC by 1.376-fold. This study is the first to examine the risk factors associated with RETN SNPs in OSCC progression and development in Taiwan.

Association of single nucleotide polymorphisms in resistin gene with rheumatoid arthritis in a Chinese population

BACKGROUND

Recent evidences have revealed that resistin is associated with the development of rheumatoid arthritis (RA). The aim of this study was to analyze the association of resistin gene single nucleotide polymorphisms (SNPs) with RA susceptibility.

METHODS

In this study, we finally analyzed three resistin SNPs (rs1862513, rs3745368, and rs3745367) in 278 RA patients and 276 normal controls recruited from Chinese population using TaqMan SNP genotyping assays.

RESULTS

There were no significant differences for the distribution of allele and genotype frequencies of these three SNPs between RA patients and normal controls (all P > .05). The genotype effects of dominant, recessive models were also analyzed, and no significant association was detected (all P > .05). Haplotype analysis suggested that the frequency of haplotype GAA was notably lower in RA patients in comparison with normal controls (OR = 0.317, 95% CI: 0.125-0.807, P = .011).

CONCLUSION

In a ward, our results indicated that resistin gene polymorphisms might affect the genetic predisposition of RA in Chinese population.

Colonic Mucosal Microbiota in Colorectal Cancer: A Single-Center Metagenomic Study in Saudi Arabia

Background and Aim

Because genetic and geographic variations in intestinal microbiota are known to exist, the focus of this study was to establish an estimation of microbiota in colorectal cancer (CRC) patients in Saudi Arabia by means of metagenomic studies.

Methods

From July 2010 to November 2012, colorectal cancer patients attending our hospital were enrolled for the metagenomic studies. All underwent clinical, endoscopic, and histological assessment. Mucosal microbiota samples were collected from each patient by jet-flushing colonic mucosa with distilled water at unified segments of the colon, followed by aspiration, during colonoscopy. Total purified dsDNA was extracted and quantified prior to metagenomic sequencing using an Illumina platform. Satisfactory DNA samples (n = 29) were subjected to metagenomics studies, followed by comprehensive comparative phylogenetic analysis. An equal number of healthy age-matched controls were also examined for colonic mucosal microbiota.

Results

Metagenomics data on 29 patients (14 females) in the age range 38-77 years were analyzed. The majority 11 (37%) of our patients were overweight (BMI = 25-30). Rectal bleeding was the presenting symptom in 18/29 (62%), while symptomatic anemia was the presenting symptom in 11/29 (37%). The location of colon cancer was rectal in 14 (48%), while cecal growth was observed in 8 (27%). Hepatic flexure growth was found in 1 (3%), descending colonic growth was found in 2 (6%), and 4 (13%) patients had transverse colon growth. The metagenomics analysis was carried out, and a total of 3.58G reads were sequenced, and about 321.91G data were used in the analysis. This study identified 11 genera specific to colorectal cancer patients when compared to genera in the control group. Bacteroides fragilis and Fusobacterium were found to be significantly prevalent in the carcinoma group when compared to the control group.

Conclusion

The current study has given an insight into the microbiota of colorectal cancer patients in Saudi Arabia and has identified various genera significantly present in these patients when compared to those of the control group.

Association of RETN and CAP1 SNPs, Expression and Serum Resistin Levels with Breast Cancer in Mexican Women

BACKGROUND

Breast cancer is the most common cancer in women worldwide. Approximately 70% of female breast cancer patients have a body mass index (BMI) >25. In obesity, adipose tissue secretes additional resistin, which prompts a proinflammatory effect through its action on adenylate cyclase-associated protein 1 (CAP1). Several studies have associated the RETN gene single nucleotide polymorphism (SNP) rs1862513 (-420C<G) with serum resistin levels and breast cancer. The CAP1 gene SNP rs35749351 (missense, Arg294His), located in the extracellular domain, has not previously been studied in cancer. These two SNPs, the mRNA expression levels of the two alleles for each of the cognate genes, and the serum resistin levels were compared between patients and controls to determine their association with breast cancer in Mexican women in this study.

MATERIALS AND METHODS

This study included 308 controls and 100 female patients with breast cancer. SNPs were detected by PCR-RFLP from DNA isolated from peripheral blood. Gene expression was performed with hydrolysis probes in tumor tissue. Resistin levels were quantified from serum samples by ELISA.

RESULTS

The RETN rs1862513CG/GG and CAP1 rs35749351GA/AA genotypes were associated with 1.61 and 2.193-fold increased risks of breast cancer, respectively, compared with the CC and GG genotypes. Similarly, carriers of the G allele of rs1862513 and the A allele of rs35749351, had 1.51 and 2.217-fold increased risks of breast cancer compared with the C and G alleles, respectively. The rs1862513GG/rs35749351AA genotype combination increased breast cancer risk by twofold. Serum resistin levels in postmenopausal breast cancer women were higher compared with postmenopausal controls. Tissue CAP1 expression showed differences with regard to molecular subtypes and metastases.

CONCLUSION

The RETN and CAP1 polymorphisms and gene expression may be potential biomarkers for breast cancer risk.

Resistin polymorphisms are associated with rheumatoid arthritis susceptibility in Chinese Han subjects

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease. To date, the specific mechanisms that drive RA disease remain unknown and provide the impetus for genetic investigations into the development of RA. Researchers hope to identify gene polymorphisms that could serve as treatment targets in patients with RA. We have previously suggested that the gene encoding the pro-inflammatory adipokine resistin (RETN) may correlate with RA development. In this report, we sought to determine whether selected RETN single nucleotide polymorphisms (SNPs) are associated with RA susceptibility and clinicopathological characteristics. Four RETN SNPs (rs3745367, rs7408174, rs1862513, and rs3219175) were assessed using TaqMan genotyping in Chinese Han patients with RA and healthy controls. We found that carriers with the C allele of the RETN SNP rs7408174 as well as those with the AG allele or who had at least one A allele of the SNP rs3219175 are at greater risk of developing RA disease compared with wild-type carriers. Moreover, RA patients with the AG allele of the RETN SNP rs3219175 had higher serum C-reactive protein expression compared with controls, and these patients had a high likelihood of being on tumor necrosis factor (TNF) inhibitor therapy. This study is the first to discuss risk factors associated with RETN SNPs in RA progression in a Chinese Han population.

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.