Association study of two inflammation-related polymorphisms with susceptibility to hepatocellular carcinoma: a meta-analysis

The Impact of General Anesthesia on Redox Stability and Epigenetic Inflammation Pathways: Crosstalk on Perioperative Antioxidant Therapy

Worldwide, the prevalence of surgery under general anesthesia has significantly increased, both because of modern anesthetic and pain-control techniques and because of better diagnosis and the increased complexity of surgical techniques. Apart from developing new concepts in the surgical field, researchers and clinicians are now working on minimizing the impact of surgical trauma and offering minimal invasive procedures due to the recent discoveries in the field of cellular and molecular mechanisms that have revealed a systemic inflammatory and pro-oxidative impact not only in the perioperative period but also in the long term, contributing to more difficult recovery, increased morbidity and mortality, and a negative financial impact. Detailed molecular and cellular analysis has shown an overproduction of inflammatory and pro-oxidative species, responsible for augmenting the systemic inflammatory status and making postoperative recovery more difficult. Moreover, there are a series of changes in certain epigenetic structures, the most important being the microRNAs. This review describes the most important molecular and cellular mechanisms that impact the surgical patient undergoing general anesthesia, and it presents a series of antioxidant therapies that can reduce systemic inflammation.

The association between micro-RNA gene polymorphisms and the development of hepatocellular carcinoma in Egyptian patients

INTRODUCTION

The development and progression of hepatocellular carcinoma (HCC) is a multistage process involving the deregulation of genes that are crucial to cellular processes. Multiple risk factors are correlated with HCC. MicroRNA is differentially expressed in the development of different types of malignancies, including hepatic malignancy. Single nucleotide polymorphisms (SNPs) are the most common sequence variation in the human genome. SNPs in miRNAs may affect transcription, processing, or target recognition and result in malignant disease. The aim of the study was to determine the association between microRNA gene polymorphisms and the development of HCC in Egyptian patients.

MATERIAL AND METHODS

This study included 200 individuals who were matched in age and sex. Tumour staging was done using the BCLC staging system. Quantification and genotyping of microRNA were performed.

RESULTS

Among the 200 patients, 2 groups were described: group I included 90 HCC patients with a male majority (72.2%), and group II comprised 110 controls. Three microRNA SNPs were assayed in both patients and controls. There was a significant association between rs10061133 miR-499b and the risk of HCC. The genotypes GG or G allele were significantly associated with an increased risk of HCC (GG: OR = 2.91, 95% CI: 1.23-4.22, p = 0.013; G allele: OR = 1.79, 95% CI: 1.12-2.15, p = 0.026) compared with the genotype of AA or AG or A allele.

CONCLUSIONS

There is an association between the miRNA SNPs and the susceptibility to HCC, to explore some roles and mechanisms of SNPs within miRNAs in the occurrence and development of HCC.

Investigation of the Association of miRNA-499, miRNA-146a, miRNA-196a2 Loci with Hepatocellular Carcinoma Risk: A Case-Control Study Involving 1507 Subjects

microRNAs' (miRNAs) loci may influence hepatocellular carcinoma (HCC) development. Many recent studies have assessed the relationship between miRNA-499, miRNA-146a, and miRNA-196a2 loci and HCC risk. However, the observed results are conflicting. A total of 584 HCC patients and 923 age- and sex-matched controls were recruited. The correlation of miRNA-499 rs3746444, miRNA-146a rs2910164, and miRNA-196a2 rs11614913 with HCC development was assessed. In the <53-year-old subgroup, a correlation of the rs2910164 locus with HCC risk was found (GG/CG vs. CC: adjusted p = 0.011, GG vs. CC: adjusted p = 0.021 and CG vs. CC: adjusted p = 0.027). The association between miRNA-146a rs2910164 and the risk of HCC was also found in the never smoking (GG/CG vs. CC: adjusted p = 0.011 and CG vs. CC: adjusted p = 0.018). Using false-positive report probability method and power value, we identified that miRNA-146a rs2910164 conferred a risk to HCC in the <53-year-old and never-smoking subgroups. In conclusion, this study indicates rs2910164 may be a risk factor for HCC, especially in the <53-year-old and never-smoking subgroups.

Association of single nucleotide polymorphisms in microRNAs with susceptibility to hepatitis B virus infection and HBV-related liver complications: A study in a Saudi Arabian population

The aim of this study was to evaluate the association of 10 SNPs in different microRNAs (miRNAs) with susceptibility to hepatitis B virus (HBV) infection, HBV clearance, persistence of chronic HBV infection, and progression to liver cirrhosis and hepatocellular carcinoma (HCC). Patients were categorized into the following groups: inactive HBV carrier, active HBV carrier, HBV-cleared subject and cirrhosis+HCC. Samples were analysed for 10 SNPs in microRNAs using either PCR-based genotyping or the TaqMan assay. We found that rs1358379 was associated with susceptibility to HBV infection, HBV clearance, persistent chronic HBV infection and liver cirrhosis+HCC. In addition, we found that rs2292832 and rs11614913 were associated with risk of HBV infection, viral clearance and cirrhosis+HCC, whereas rs2910164 was associated with proneness to HBV infection, and ability to clear the virus. There was evidence of associations between rs6505162 and HBV clearance and the development of liver disease, whereas a single association was found between rs2289030 and HBV clearance. Similarly, rs7372209 and rs4919510 were specifically associated with the development of HBV-induced liver complications. SNPs in miRNAs affect the susceptibility, clearance and progression of HBV infection in Saudi Arabian patients. We found, using Gene Ontology or pathway analyses, that these genes may contribute to the pathophysiology of HBV infection and related liver complications. However, differences in the association of examined SNPs with various clinical stages indicate variations in the respective functional roles of these polymorphisms and their miRNAs, and thus, further investigation to fully explore their therapeutic potential is warranted.

MiR-146a and miR-196a-2 polymorphisms are associated with hepatitis virus-related hepatocellular cancer risk: a meta-analysis

Previous studies have investigated the role of miR-146a rs2910164 and miR-196a-2 rs11614913 polymorphisms in hepatocellular carcinoma (HCC) susceptibility, but the results are contradictory and few specifically studied hepatitis virus-related HCC. Therefore, we conducted a meta-analysis to evaluate the association between these two polymorphisms and hepatitis virus-related HCC risk. We performed a systematical search in EMBASE, PubMed, Web of Science, CNKI and Wanfang databases as of 25th November, 2016. Finally, we assessed 14 studies involving 3852 cases and 5275 controls. Our results suggest that rs2910164 has a significant association with increased hepatitis virus-related HCC risk in allelic, homozygous, heterozygous, and dominant models (CG+GG vs. CC: OR=1.22, 95% CI=1.06-1.39, P=0.004), particularly in Chinese and HBV-related HCC subgroups. Conversely, rs11614913 was associated with lower hepatitis virus-related HCC risk in the overall analysis under allelic (T vs. C: OR=0.85, 95% CI=0.74-0.98, P=0.02), homozygous, dominant and recessive models. Subgroup analyses showed decreased risk in Chinese, HBV- and HCV-related HCC. In conclusion, miR-146a C>G (rs2910164) can increase HBV-related HCC risk while miR-196a-2 C>T (rs11614913) may decrease the risk of HBV- and HCV-related HCC, especially in the Chinese population. Further, large-scale studies including other races are required to confirm these findings.

MicroRNA‑499 rs3746444 A/G polymorphism functions as a biomarker to predict recurrence following endoscopic submucosal dissection in primary early gastric cancer

The aim of the present study was to investigate the molecular mechanism, including the potential regulatory and signaling pathways, of platelet‑derived growth factor receptor β (PDGFRB), which underlies the recurrence of early gastric cancer (EGC) following endoscopic submucosal dissection (ESD). Online microRNA (miRNA) target prediction tools were used, which identified PDGFRB as the candidate target gene of miR‑499a in gastric cancer cells, and PFGRBR was then confirmed as the direct gene using a luciferase reporter assay system. The Kaplan‑Meier method was used to plot recurrence‑free curves, which were compared between genotype groups. A negative regulatory association between miR‑499a and PDGFRB was established by investigating the relative luciferase activity at different concentrations of miR‑499a mimics. Furthermore, as the rs3746444 polymorphism has been previously reported to interfere with the expression of miR‑499a, the present study investigated the expression levels of different genotypes, including TT (n=20), TC (n=9) and CC (n=3), the results of which supported the hypothesis that the presence of the minor allele (C) of the rs3746444 polymorphism compromised the expression of miR‑499a. The present study also performed polymerase chain reaction and western blot analyses to examine the mRNA and protein expression levels of PFGRBR among different genotypes or cells treated with different concentrations of miR‑499a mimics/inhibitors, which indicated the negative regulatory association between miR‑499a and PDGFRB. The present study also investigated the relative viabilities of EGC cells transfected with miR‑499a mimics (50 and 100 nM) and miR‑499a inhibitors (100 nM), and confirmed that miR‑499a negatively interfered with the viability of the EGC cells. The miR‑499a rs3746444 polymorphism was also recognized as a biomarker to predict recurrence following ESD in patients with EGC via analyzing the recurrence‑free rates among patients with EGC with different genotypes. The results showed that PDGFRB was validated as a target of miR‑499a, and rs3746444 was identified as a potential biomarker to predict the recurrence of EGC following ESD.

Association of the genetic polymorphisms in pre-microRNAs with risk of childhood epilepsy in a Chinese population

PURPOSE

MicroRNA (miRNA), functions as gene regulators, plays crucial roles in pathogenesis of epilepsy. We hypothesized that single nucleotide polymorphisms (SNPs) in miRNA may be associated with childhood epilepsy.

METHOD

We first genotyped the selected four SNPs (miR-146a rs57095329, miR-149 rs2292832, miR-196a2 rs11614913, and miR-499 rs3746444) in 267 paired childhood epilepsy patients and controls using the TaqMan assay, and evaluated the associations of the four SNPs with the risk of epilepsy. In addition, we evaluated the associations of these SNPs with drug-resistance in 95 drug-resistant and 172 drug-responsive epilepsy patients. Furthermore, the genotype-phenotype correlation was assessed in 95 drug-resistant epilepsy patients.

RESULTS

The selected four SNPs (miR-146a rs57095329, miR-149 rs2292832, miR-196a2 rs11614913, and miR-499 rs3746444) were not significantly different between epilepsy patients and controls (P>0.05 for all). However, the miR-146a rs57095329 A/G genotypes were significantly associated with increased drug-resistance risk of epilepsy patients in allelic comparison (OR=2.363, 95%CI=1.608-3.472, P<0.001), heterozygote model (OR=2.341, 95%CI=1.301-4.211, P=0.005), homozygote model (OR=1.791, 95%CI=1.239-2.589, P=0.002), dominant model (OR=2.625, 95%CI=1.558-4.425, P<0.001), and recessive model (OR=2.336, 95%CI=1.166-4.673, P=0.017). Moreover, subjects with the rs57095329 GG genotype had significantly higher NHS3 score than subjects with AA genotype (P<0.001) and AG genotype (P=0.013) in the drug resistant patients.

CONCLUSION

miR-146a rs57095329 polymorphism might be involved in the genetic susceptibility to drug-resistance and seizure severity in childhood epilepsy patients.

Oncomirs miRNA-221/222 and Tumor Suppressors miRNA-199a/195 Are Crucial miRNAs in Liver Cancer: A Systematic Analysis

BACKGROUND

The high mortality rate of hepatocellular carcinoma (HCC) is partly due to a lack of good diagnostic markers and treatment strategies. Recently, several microRNA (miRNA) profiling studies were conducted with HCC; however, their inconsistency means that their diagnostic or therapeutic value is debatable.

AIMS

This study aims to systematically evaluate the consistency of miRNAs from multiple independent studies.

METHODS

A systematic analysis of miRNAs from eligible publications was conducted, followed by real-time PCRs. The targets of highly consistent miRNAs were collected using online programs, followed by enrichment analyses for gene ontology terms and Kyoto encyclopedia of genes and genomes pathways.

RESULTS

In total, 241 differentially expressed miRNAs were reported in 13 HCC profiling studies, of which 137 were upregulated and 104 downregulated. Among consistently upregulated miRNAs (cutoff > fourfold), miRNA-222, miRNA-21, miRNA-221, miRNA-210, and miRNA-224 were found increased in 8, 6, 6, 5, and 5 different studies, respectively. Among 137 downregulated miRNAs, miRNA-195, miRNA-199a, miRNA-125b, and miRNA-99a were reported in 8, 8, 5, and 5 studies, respectively. These results were confirmed by real-time PCR. Enrichment analyses demonstrated that programmed cell death and proliferation play important roles during the interplay of miRNA with HCC.

CONCLUSIONS

miRNAs most consistently related to HCC are oncomirs miRNA-221/222 and tumor suppressors miRNA-199a/195.

Common functional polymorphism within miR-146a and miR-196a-2 as susceptibility loci for hepatocellular carcinoma: An updated meta-analysis

BACKGROUND

Mutations or single nucleotide polymorphisms (SNPs) within the gene region of microRNAs play an important role for the development of hepatocellular carcinoma (HCC). Extensive studies have tried to investigate the susceptibility role of miR-146a rs2819164 and miR-196a-2 rs11614913. However, these results are still inconsistent and inconclusive. We undertook a meta-analysis containing primarily Asian studies to assess the associations of the two SNPs with HCC risk.

METHODS

19 studies including miR-146a (7170 cases and 9443 controls) and 15 studies including miR-196a-2 (6417 cases and 7627 controls) were used for meta-analysis. Odds ratios and 95% CI were calculated to assess the association in five different genetic models.

RESULTS

For the rs2910164 polymorphism of miR-146a, significantly increased risks for HCC were observed when all studies were pooled under two models (CG vs CC: OR = 1.11, 95% CI = 1.02-1.21, P = 0.021; GG + CG vs CC: OR = 1.11, 95% CI = 1.01-1.22, P = 0.035). For the rs11614913 polymorphism of miR-196a-2, significant increased risks for HCC development were observed when all studies were pooled under four models (C vs T: OR = 1.14, 95% CI = 1.06-1.23, P = 0.001; CC vs TT: OR = 1.31, 95% CI = 1.12-1.53, P = 0.001; CC + TC vs TT: OR = 1.16, 95% CI = 1.03-1.31, P = 0.018; CC vs TC + TT: OR = 1.14, 95% CI = 1.00-1.30, P = 0.043).

CONCLUSION

Our results show that the two common SNPs within the miRNAs were associated with modest increased risk of HCC (OR < 1.6), especially in the Asian population. Larger population-based studies validating these results are needed.

The occurrence of cervical cancer in Uygur women in Xinjiang Uygur Autonomous Region is correlated to microRNA-146a and ethnic factor

AIMS

The present study is to investigate the effect of microRNA-146a (miR-146a) and ethnic factor in the occurrence of cervical cancer in Uygur women in Xinjiang Uygur Autonomous Region.

METHODS

A total of 620 pieces of cervical tissues were obtained between September 2010 and September 2013, including 208 cases of cervicitis, 207 cases of cervical intraepithelial neoplasia, and 205 cases of cervical cancer. The relative expression of miR-146a in tissues was measured using quantitative real-time polymerase chain reaction. Polymerase chain reaction - restriction fragment length polymorphism was used to determine the genotypes of miR-146a (rs2910164). Differences between two groups and multiple groups were compared using t-test and one-factor analysis of variance, respectively. Comparison of genotype compositions and genetic balance examinations were performed using χ(2) test.

RESULTS

Uygur women had earlier age of marriage, more times of pregnancy, and more childbirths than Han women. The miR-146a (rs2910164) genotype composition was significantly different between Uygur and Han, with the ratio of GG genotype in Uygur being higher than that in Han. Logistic regression analysis showed that miR-146a (rs2910164) genotypes were significantly correlated to ethnic factor and tumor sizes. The expression of miR-146a was elevated in cervical intraepithelial neoplasia and cervical cancer, especially for Uygur women, with the GG genotype being the most highly expressed.

CONCLUSIONS

The miR-146a (rs2910164) polymorphism is significantly correlated to ethnic factor and tumor diameters. miR-146a has differential expression in cervical tissues. Allele G of miR-146a (rs2910164) is related to the high expression of miR-146a, and the progression of cervical cancer.

Targeting miR-146a to treat delayed wound healing in human diabetic organ-cultured corneas

Limbal epithelial stem cells (LESC) residing at the corneal periphery are largely responsible for maintaining corneal optical transparency by continuously supplying new corneal epithelial cells, which mature during their radial migration to the central cornea. Diabetes mellitus (DM) affects all the structures of the eye including the cornea. Frequent epithelial erosions, delayed wound healing, and microbial infections are common alterations of the diabetic eye that can result in vision loss. MicroRNAs (miRNAs) are short non-coding oligonucleotides that regulate gene expression by repressing translation. Our purpose was to understand the role of miR-146a in the human limbal versus central corneal epithelial compartment in normal and pathological conditions such as diabetes mellitus. Using quantitative real-time PCR (QPCR) we found miR-146a enrichment in the limbal corneal compartment. This miRNA was also expressed at higher levels in the diabetic vs. normal limbus. Cell migration and wound closure were significantly delayed in normal and diabetic primary limbal epithelial cells (LEC) transfected with miR-146a. Cells treated with miR-146a had decreased levels of phosphorylated (activated) p38 and EGFR, mediators of epithelial wound healing. Conversely, inhibition of miR-146a significantly enhanced cell migration in both normal and diabetic primary LEC and in diabetic organ-cultured corneas by nearly 40% vs. scrambled miRNA control, accompanied by increased phosphorylated signaling intermediates. Transfection of miR-146a in cultured LEC resulted in an increased immunoreactivity for putative LEC markers Frizzled-7 and K15, whereas inhibition of miR-146a decreased their expressions. These data suggest that miR-146a plays a role in LEC maintenance at the corneal periphery, and its expression is downregulated during their migration towards the central cornea and accompanying terminal differentiation. Furthermore, abnormal miR-146a upregulation may be an important mechanism of delayed wound healing in the diabetic cornea.