A variant in microRNA-196a2 is associated with susceptibility to hepatocellular carcinoma in Chinese patients with cirrhosis

Effect of miR-196a2 rs11614913 Polymorphism on Cancer Susceptibility: Evidence From an Updated Meta-Analysis

Background:MiR-196a2 rs11614913 polymorphism has been studied in a wide range of cancers throughout the years. Despite a large number of epidemiological studies performed in almost all ethnic populations, the contribution of this polymorphism to cancer risk is still inconclusive. Therefore, this updated meta-analysis was performed to estimate a meticulous correlation between miR-196a2 rs11614913 variant and cancer susceptibility. Methods: A systematic study search was carried out using PubMed, ScienceDirect, CNKI, EMBASE, Scopus, and Google Scholar databases following PRISMA guidelines to find necessary literature up to December 15, 2021. Pooled odds ratios with corresponding 95% confidence intervals were estimated using RevMan 5.4 based on ethnicities, cancer types, control sources, and genotyping methods. Results: A total of 152 studies, including 120 135 subjects (53 818 patients and 66 317 controls; 140 studies, after removing studies that deviated from HWE: 51 459 cases and 62 588 controls), were included in this meta-analysis. Quantitative synthesis suggests that the miR-196a2 rs11614913 genetic variant is significantly correlated with the reduced risk of overall cancer in CDM2, CDM3, RM, and AM (odds ratio < 1 and P < .05). It is also observed from ethnicity-based subgroup analysis that rs11614913 polymorphism is significantly (P < .05) linked with cancer in the Asian (in CDM2, CDM3, RM, AM) and the African population (in CDM1, CDM3, ODM). Stratified analysis based on the cancer types demonstrated a significantly decreased correlation for breast, hepatocellular, lung, and gynecological cancer and an increased association for oral and renal cell cancer. Again, the control population-based subgroup analysis reported a strongly reduced correlation for HB population in CDM2, RM, and AM. A substantially decreased risk was also observed for other genotyping methods in multiple genetic models. Conclusions:MiR-196a2 rs11614913 variant is significantly correlated with overall cancer susceptibility. Besides, rs11614913 is correlated with cancer in Asians and Africans. It is also correlated with breast, gynecological, hepatocellular, lung, oral, and renal cell cancer.

MicroRNA polymorphism: A target for diagnosis and prognosis of hepatocellular carcinoma?

Hepatocellular carcinoma (HCC) is a life-threatening cancer of the digestive system, with complex pathogenesis affected by a broad spectrum of genetic and epigenetic factors. Among several factors, microRNAs (miRNAs), which are considered regulators of the post-transcriptional gene expression, play important roles in determining the malignant phenotype of HCC. In recent years, the advances in molecular genetics have resulted in the characterization of complex genetic factors and in the identification of epigenetic mechanisms of diseases. Accumulating data have suggested that miRNA polymorphisms are involved in tumorigenesis and prognosis, suggesting that the miRNAs may serve as a target for HCC with regard to pathogenesis and prognosis. In the present review, a comprehensive and detailed literature search was conducted and the role of miRNA polymorphisms in the pathogenesis and prognosis of HCC is summarized. The data proposed the use of miRNAs as targets for the diagnosis and treatment of HCC.

Association between miR-196a2 polymorphism and the development of hepatocellular carcinoma in the Egyptian population

Background

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers worldwide. Circulating microRNAs (miRNAs) are endogenous, small (17–25 nucleotides) non-coding RNAs that are overexpressed in many human cancers including HCC. Single-nucleotide polymorphisms (SNPs) of miRNAs play an important role in the pathogenesis of HCC. In our study, we aimed to evaluate the role of miR-196a2 rs11614913 polymorphism in the development of HCC. A total of 200 subjects, including 80 HCC patients, 60 patients with liver cirrhosis, and 60 healthy controls were selected. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was taken to determine miR-196a2 rs11614913 polymorphism.

Results

The genotype distribution of the TC and CC, TC + CC genotypes, and the C allele were significantly higher in HCC patients than control and cirrhotic groups (P = 0.02, P = 0.005, and P = 0.003, respectively). Compared with the wild-type TT genotype, both the variant TC, CC, TC + CC genotypes were associated with an elevated risk of HCC (OR = 2.77, 95% CI = 1.27–6.04), (OR = 4.94, 95% CI = 1.74–14.07), (OR = 3.24, 95% CI = 1.55–6.78) respectively. Moreover, the C allele was correlated with an increased risk of HCC (OR = 2.30, 95% CI = 1.40–3.76) compared to the wide-type T allele. Also, there is no significant correlation between the different miR-196a2 genotypes and either the clinico-pathologic features of HCC or its aggressiveness.

Conclusion

Our results suggest that the miR-196a2 rs11614913 polymorphism is associated with an increased risk of HCC in the Egyptian population.

Association of mir-196a-2 rs11614913 and mir-149 rs2292832 Polymorphisms With Risk of Cancer: An Updated Meta-Analysis

Background: Accumulating evidence suggests that functional dysregulations of miRNAs, especially miR-196a-2 and miR-149, in cancers could be attributed to polymorphisms in miRNA sequences. This study was aimed at clarifying the association of mir-196a-2 rs11614913 and mir-149 rs2292832 with cancer risk by performing an updated meta-analysis of genetic association studies. Methods: PubMed, Embase, Scopus, and ScienceDirect databases were searched until 9 April 2018 to identify eligible studies. Studies should meet the following criteria to be included in the meta-analysis: evaluation of genetic association between rs11614913 and/or rs2292832 and susceptibility to cancer; A case-control design; Written in English; Availability of sufficient data for estimating odds ratio (OR) and its 95% confidence interval (95%CI). Studies that met the following criteria were excluded: review articles, meta-analysis, abstracts or conference papers; duplicate publications; studies on animals or cell-lines; studies without a case-control design; studies that did not report genotype frequencies. Pooled ORs and 95% CIs were estimated using a total of 111 studies (41,673 cases and 49,570 controls) for mir-196a rs11614913 and 44 studies (15,954 cases and 19,594 controls) for mir-149 rs2292832. Stratified analysis according to quality scores, genotyping method, ethnicity, broad cancer category and cancer type was also performed. Results: Mir-196a-2 rs11614913 T allele was associated with decreased cancer risk in overall population. The association was only significant in Asians but not Caucasians. In subgroup analysis, significant associations were found in high quality studies, gynecological cancers, ovarian, breast, and hepatocellular cancer. Mir-149 rs2292832 was not associated with cancer risk in overall population and there were no differences between Asians and Caucasians. However, the T allele was associated with a decrease risk of gastrointestinal tract cancers under the heterozygote model and an increased risk of colorectal cancer under the recessive model. Conclusions: The present meta-analysis suggests that mir-196a-2 rs11614913 may contribute to the risk of cancer especially in Asians. Mir-149 rs2292832 may modulate the risk of gastrointestinal tract cancers especially colorectal cancer. This study had some limitations such as significant heterogeneity in most contrasts, limited number of studies enrolling Africans or Caucasians ancestry and lack of adjustment for covariates and environmental interactions.

Comprehensive assessment for miRNA polymorphisms in hepatocellular cancer risk: a systematic review and meta-analysis

MiRNA polymorphisms had potential to be biomarkers for hepatocellular cancer (HCC) susceptibility. Recently, miRNA single nucleotide polymorphisms (SNPs) were reported to be associated with HCC risk, but the results were inconsistent. We performed a systematic review with a meta-analysis for the association of miRNA SNPs with HCC risk. Thirty-seven studies were included with a total of 11821 HCC patients and 15359 controls in this meta-analysis. We found hsa-mir-146a rs2910164 was associated with a decreased HCC risk in the recessive model (P=0.017, OR = 0.90, 95% confidence interval (CI) = 0.83–0.98). While hsa-mir-34b/c rs4938723 was related with an increased HCC risk in the co-dominant model (P=0.016, odds ratio (OR) = 1.19, 95%CI = 1.03–1.37). When analyzing the Hepatitis B virus (HBV)-related HCC risk, hsa-mir-196a-2 rs11614913 was associated with a decreased HBV-related HCC risk in the co-dominant and allelic models. And hsa-mir-149 rs2292832 was found to be associated with a decreased HBV-related HCC risk in the dominant and recessive models. In conclusion, hsa-mir-146a rs2910164 and hsa-mir-34b/c rs4938723 could be biomarkers for the HCC risk while hsa-mir-196a-2 rs11614913 and hsa-mir-149 rs2292832 had potential to be biomarkers for HBV-related HCC risk.

rs11614913 polymorphism in miRNA-196a2 and cancer risk: an updated meta-analysis

Several epidemiological studies have reported that polymorphisms in microRNA-196a2 (miR-196a2) were associated with various cancers. However, the results remained unverified and were inconsistent in different cancers. Therefore, we carried out an updated meta-analysis to elaborate the effects of rs11614913 polymorphism on cancer susceptibility. A total of 84 articles with 35,802 cases and 41,541 controls were included to evaluate the association between the miR-196a2 rs11614913 and cancer risk by pooled odds ratios (ORs) and 95% confidence intervals (CIs). The results showed that miR-196a2 rs11614913 polymorphism is associated with cancer susceptibility, especially in lung cancer (homozygote comparison, OR =0.840, 95% CI =0.734-0.961; recessive model, OR =0.858, 95% CI =0.771-0.955), hepatocellular carcinoma (allelic contrast, OR =0.894, 95% CI =0.800-0.998; homozygote comparison, OR =0.900, 95% CI =0.813-0.997; recessive model, OR =0.800, 95% CI =0.678-0.944), and head and neck cancer (allelic contrast, OR =1.076, 95% CI =1.006-1.152; homozygote comparison, OR =1.214, 95% CI =1.043-1.413). In addition, significant association was found among Asian populations (allele model, OR =0.847, 95% CI =0.899-0.997, P=0.038; homozygote model, OR =0.878, 95% CI =0.788-0.977, P=0.017; recessive model, OR =0.895, 95% CI =0.824-0.972, P=0.008) but not in Caucasians. The updated meta-analysis confirmed the previous results that miR-196a2 rs11614913 polymorphism may serve as a risk factor for patients with cancers.

Functional miR-146a, miR-149, miR-196a2 and miR-499 polymorphisms and the susceptibility to hepatocellular carcinoma: An updated meta-analysis

OBJECTIVE

Single nucleotide polymorphisms of miRNAs play important roles in the pathogenesis of hepatocellular carcinoma (HCC). To evaluate the association between four common miRNAs (miR-146a rs2910164; miR-149 rs2292832; miR-196a2 rs11614913 and miR-499 rs3746444) and HCC risk, an updated meta-analysis was performed.

METHODS

32 studies including 12,405 HCC cases and 15,056 controls were used for this meta-analysis. There were 22 studies with 7894 cases and 10,221 controls for miR-146a, 9 studies with 2684 HCC cases and 3464 controls for miR-149, 17 studies with 6937 cases and 8217 controls for miR-196a2 and 16 studies with 4158 cases and 5264 controls for miR-499. Odds radios (ORs) and 95% confidence intervals (CIs) were used to assess the HCC risk.

RESULTS

Meta-analysis showed that miR-146a was associated with HCC risk under the heterozygote model (OR=1.10, 95%CI=1.03-1.17, P=0.007), whereas no association was found in Caucasian using all genetic models. For miR-196a2 polymorphism, an increased risk of HCC was observed based on four models (C vs T: OR=1.15, 95%CI=1.05-1.26, P=0.003; CC vs TT: OR=1.35, 95%CI=1.12-1.63, P=0.002; CC+CT vs TT: OR=1.20, 95%CI=1.04-1.37, P=0.01 and CC vs CT+TT: OR=1.23, 95%CI=1.06-1.42, P=0.006). Association of miR-499 with HCC risk was only detected in the subgroup of studies which did not use polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) under the allelic, heterozygote and dominant models. However, negative results were obtained for the association of miR-149 and HCC susceptibility.

CONCLUSION

Our results suggest that miR-146a and miR-196a2 polymorphisms are associated with increased risk of HCC, especially in Asian.

Association of miR-196a2 rs11614913 and miR-499 rs3746444 polymorphisms with cancer risk: a meta-analysis

Background

MicroRNAs (miRNAs) are small non-coding RNA molecules, which participate in diverse biological processes and may regulate tumor suppressor genes or oncogenes. Rs11614913 in miR-196a2 and rs3746444 in miR-499 are shown to associate with increased/decreased cancer risk. This meta-analysis was performed to systematically assess the overall association.

Materials and Methods

We searched Pubmed, Web of Knowledge, EMBASE, Chinese National Knowledge Infrastructure (CNKI) databases until December 2016 to identify eligible studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the strength of the associations.

Results

We assessed published studies of the association between these microRNA polymorphisms and cancer risk from 56 studies with 21958/26436 cases/controls for miR-196a2 and from 37 studies with 13759/17946 cases/controls for miR-499. The results demonstrated that miR-196a2 rs11614913 was significantly associated with a decreased cancer risk, in particular with a decreased risk for colorectal cancer and gastric cancer, or for Asian population subgroup. In addition, miR-499 rs3746444 polymorphism was observed as a risk factor for cancers, in particular, for breast cancer, or for in the Asian population.

Conclusions

Our meta-analysis suggests that the rs11614913 most likely contributes to decreased susceptibility to cancer, especially in Asians and colorectal cancer and gastric cancer, and that the rs3746444 may increase risk for cancer. Furthermore, more well-designed studies with large sample size are still necessary to further elucidate the association between polymorphisms and different kinds of cancers risk.

Meta-analysis of the association between three microRNA polymorphisms and breast cancer susceptibility

Single nucleotide polymorphisms (SNPs) in three microRNAs (miRNAs), rs2910164 in miR-146a, rs11614913 in miR-196a2, and rs3746444 in miR-499, have been associated with breast cancer (BC) susceptibility, but the evidence is conflicting. To obtain a more robust assessment of the association between these miRNA variants and BC risk, we carried out a meta-analysis through systematic literature retrieval from the PubMed and Embase databases. A total of 9 case-control studies on rs2910164, 12 on rs11614913, and 7 on rs3746444 were included. Pooled odds ratios and 95% confidence intervals were used to evaluate associations with BC risk. Overall analysis showed that rs2910164 was not associated with BC susceptibility in any genetic model, whereas rs11614913 was associated with a decreased risk in both the allelic contrast and recessive models, and rs3746444 imparted an increased risk in all genetic models. Stratified analyses showed that rs11614913 may decrease the risk of BC in the heterozygote model in Asians, and in all genetic models, except the heterozygote model, when the sample size is ≥ 500. Subgroup analysis indicated that rs3746444 was associated with increased risk of BC in Asians, but not Caucasians, at all sample sizes. This meta-analysis suggests that rs11614913 in miR-196a2 may decrease the risk of BC, while rs3746444 in miR-499 may increase it, especially in Asians when the sample size is large. We propose that rs11614913(C > T) and rs3746444 (A > G) may be useful biomarkers predictive of BC risk.

Functional polymorphisms in pre-miR146a and pre-miR499 are associated with systemic lupus erythematosus but not with rheumatoid arthritis or Graves' disease in Mexican patients

Recently, different microRNA (miRNA) gene polymorphisms have been evaluated in patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and Graves’ disease (GD). In the present study, we examined three single-nucleotide polymorphisms (SNPs) located in the pre-miR-146a (rs2910164G/C), pre-miR-196a-2 (rs11614913C/T), and pre-miR-499 (rs3746444A/G) genes. Our study population included 900 Mexican patients with RA, SLE, or GD, as well as 486 healthy control individuals with no family history of inflammatory or autoimmune diseases. Genotyping was performed using TaqMan probes and a 5′ exonuclease assay. None of the investigated SNPs were associated with RA or GD susceptibility under any genetic model (co-dominant, recessive, or dominant). Genotype and allele frequencies of the miR-196a-2 rs11614913C/T polymorphism were similar between SLE cases and controls. In contrast, the miR-146a rs2910164G/C and miR-499 rs3746444A/G polymorphisms were associated with SLE susceptibility. These SNPs were not associated with lupus nephritis (LN). Our results suggest that polymorphisms in miR-146a, miR-196a-2, and miR-499 are not associated with RA or GD susceptibility. This is the first report documenting that the miR-146a rs2910164G/C and miR-499 rs3746444 polymorphisms are associated with SLE susceptibility but not with LN.

MIR196A2 rs11614913 C > T polymorphism correlates with an increased risk of hepatopulmonary syndrome in liver cirrhosis: a case-control study in China

OBJECTIVE

This case-control study is designed to explore the relationship between microRNA-196a2 (MIR196A2) rs11614913 C > T polymorphism and the risk of hepatopulmonary syndrome (HPS) in liver cirrhosis.

METHODS

From January 2013 to January 2015, 163 liver cirrhosis patients with HPS (case group), 264 liver cirrhosis patients without HPS (control group), and 195 healthy people (normal group) were selected. A DNA extraction kit was used to extract plasma DNA from peripheral blood. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the allele and genotype frequencies of MIR196A2 C > T polymorphism. Real-time quantitative polymerase chain reaction was adopted to detect the relative expression of MIR196A.

RESULTS

The frequencies of C allele in the case group were higher than those in the control and normal groups (all P < 0.05), whereas no significant difference was found between the control and normal groups, which indicated that MIR196A2 C > T polymorphism was closely associated with an increased risk of HPS in patients with liver cirrhosis. Compared with the normal group, the relative expression of MIR196A in the case group was significantly increased (P < 0.05), but there was no significant difference in the control group (P > 0.05). In the case group, compared with patients carrying the TT genotype, the relative expression of MIR196A of patients carrying the C allele (CT + CC) evidently increased (P < 0.05).

CONCLUSIONS

The MIR196A2 rs11614913 C > T polymorphism may contribute to an increased risk of HPS in liver cirrhosis patients.

The role of microRNA-196a in tumorigenesis, tumor progression, and prognosis

MicroRNAs are a large group of non-coding RNAs that have emerged as regulators of various biological processes, especially carcinogenesis and cancer progression. Recent evidence has shown that microRNA-196a (miR-196a) is upregulated in most types of tumors and involved in multiple biological processes via translational inhibition and mRNA cleavage, such as cell proliferation, migration, and invasion, mostly functioning as an oncogene. Dysregulation of miR-196a promotes oncogenesis and tumor progression. In this review, we summarize the upstream regulators, target genes, signaling pathways, and single nucleotide polymorphisms of miR-196a, which collectively affect cell proliferation, migration, and invasion. In addition, we review the clinical outcomes and significance of miR-196a. miR-196a may serve as a novel biomarker or target for diagnosis, prognosis, and therapy in several human cancers.

Single Nucleotide Polymorphisms in miR-149 (rs2292832) and miR-101-1 (rs7536540) Are Not Associated with Hepatocellular Carcinoma in Thai Patients with Hepatitis B Virus Infection

MicroRNAs directly and indirectly influence many biological processes such as apoptosis, cell maintenance, and immune responses, impacting on tumor genesis and metastasis. They modulate gene expression at the post- transcriptional level and are associated with progression of liver disease. Hepatocellular carcinoma (HCC) is a cancer which mostly occurs in males. There are many factors affect HCC development, for example, hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV), co-infection, environmental factors including alcohol, aflatoxin consumption and host-related factors such as age, gender immune response, microRNA and single nucleotide polymorphisms (SNPs). Chronic infection with the hepatitis B virus is the major factor leading to HCC progression since it causes the liver injury. At present, there are many reports regarding the association of SNPs on miRNAs and the HCC progression. In this research, we investigated the role of miR- 149 (rs2292832) and miR-101-1 (rs7536540) with HCC progression in Thai population. The study included 289 Thai subjects including 104 HCC patients, 90 patients with chronic hepatitis B virus infection (CHB) and 95 healthy control subjects. The allele and genotype of rs2292832 and rs7536540 polymorphisms were determined by TaqMan real-time PCR assay. Our results revealed no significant association between miR-149 (rs2292832) and miR-101-1 (rs7536540) and the risk of HCC in our Thai population. However, this research is the first study of miR-149 (rs2292832) and miR-101-1 (rs7536540) in HCC in Thai populations and the results need to be confirmed with a larger population.

A Single-Nucleotide Polymorphism of miR-196a2T>C rs11614913 Is Associated with Hepatocellular Carcinoma in the Chinese Population

OBJECTIVE

We investigated the miR-196a2T>C rs11614913 variant in the initiation and progression of hepatocellular carcinoma (HCC).

METHODS

A case-control research model was conducted and the genotypes of 109 HCC patients and 105 healthy controls were identified by direct sequencing. The correlation between the rs11614913 genotypes and the susceptibility to HCC was evaluated using an unconditional logistic regression model.

RESULTS

We found that 20/109 (18.3%) patients were TT homozygote, whereas 64/109 (58.8%) patients had the CT genotype, and 25/109 (22.9%) patients had the CC genotype. In control samples, the frequency of the TT homozygote was 33.3%, that of CT was 49.5%, and that of CC was 17.1%. After adjusting for age and gender by logistic regression analysis, we found significant differences in susceptibility to HCC by genotype (TT vs. CT+CC: OR = 2.52, 95%CI = 1.18-4.19; p < 0.05). The CT and CC genotypes were more common in HCC patients compared to controls. Moreover, the CT+CC genotypes were associated with a poor HCC prognosis.

CONCLUSIONS

In this study, we found that the CT+CC genotypes of rs11614913 were significantly associated with an increased risk and poor prognosis for HCC in the Chinese population.

Somatic Mutation of the SNP rs11614913 and Its Association with Increased MIR 196A2 Expression in Breast Cancer

Common genetic variants (single-nucleotide polymorphisms [SNPs]) in microRNA genes may alter their maturation or expression, resulting in varied functional consequences. Several studies have evaluated the association between the SNP rs11614913 and cancer risk in diverse populations and in a range of cancers, with contradictory outcomes. In this study, we examined 114 paired samples (tumor and normal tissues) from breast cancer patients to study the genotype distribution and somatic mutation of the SNP in MIR 196A2 (rs11614913 C-T). In addition, we evaluated their influence on the mature MIR 196A2 expression. We found that 14% (16/114) of tumors underwent somatic mutation of the SNP rs11614913. Moreover, the CT heterozygous and the CC homozygous states of SNP rs11614913 were more prone to mutation, while the TT homozygous state appeared to be resistant. We further detected a significant increase (p = 0.002) in mature MIR 196A2 expression in breast cancer. In particular, we found a significant association between the occurrence of SNP rs11614913 mutation and high expression (p = 0.0002). In addition, the mature MIR 196A2 expression level was significantly associated with the higher tumor grade (p = 0.004). Taken together, our results seem to demonstrate that somatic mutation of SNP rs11614913 in MIR 196A2 can have an influence on its expression. In addition, it indicated that an unknown mechanism is responsible for both the mutation of SNP rs11614913 and the dysregulation of mature MIR 196A2 expression.

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.

Non-Coding RNAs in Primary Liver Cancer

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver with poor prognosis and limited therapeutic options. Over the past few years, many studies have evaluated the role of non-coding RNAs (ncRNAs) in hepatocarcinogenesis and tumor progression. ncRNAs were shown to have diagnostic, prognostic, and therapeutic potential in HCC. In this manuscript, we review the latest major discoveries concerning microRNAs and long ncRNAs in HCC pathogenesis, and discuss the potentials and the limitations for their use in clinical practice.

Effects of Two Common Polymorphisms rs2910164 in miR-146a and rs11614913 in miR-196a2 on Gastric Cancer Susceptibility

Background. Single nucleotide polymorphisms (SNPs) in genes encoding microRNAs may play important role in the development of gastric cancer. It has been reported that common SNPs rs2910164 in miR-146a and rs11614913 in miR-196a2 are associated with susceptibility to gastric cancer. The published results remain inconclusive or even controversial. A meta-analysis was conducted to quantitatively assess potential association between the two common SNPs and gastric cancer risk. Methods. A comprehensive literature search was performed in multiple internet-based electronic databases. Data from 12 eligible studies were extracted to estimate pooled odds ratios (ORs) and 95% confidence intervals (95% CI). Results. C allele of rs2910164 is associated with reduced gastric cancer risk in heterozygote model and dominant model whereas rs11614913 indicates no significant association. Subgroup analysis demonstrates that C allele of rs2910164 and rs11614913 may decrease susceptibility to diffuse type gastric cancer in dominant model and recessive model, respectively, while rs11614913 increased intestinal type gastric cancer in dominant model. Conclusion. SNPs rs2910164 and rs11614913 might have effect on gastric cancer risk in certain genetic models and specific types of cancer. Further well-designed studies should be considered to validate the potential effect.

The "Macro" World of microRNAs in Hepatocellular Carcinoma

Hepatotropic viruses such as hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major etiological agents associated with development of hepatocellular carcinoma (HCC). Progression of HCC is a multistep process that requires sequential or parallel deregulation of oncogenic and tumor suppressive pathways leading to chromosomal instability and neoplastic phenotype. In the recent years, microRNAs (miRNAs) have carved their own niche alongside oncogenes and tumor suppressors, owing to their innate ability to receive and relay multiple signals. Not surprisingly, miRNAs are fast emerging as central player in myriads of malignancies including HCC. miRNAs are reported to participate in initiation and progression of HCC, and have also been clinically correlated with risk assessment, disease grade, aggressiveness, and prognosis. Despite extensive data available on the role of miRNAs in HCC, there is a pressing need to integrate and evaluate these datasets to find its correlation, if any, with causal agents in order to devise novel interventional modalities. Through this review, we attempt to bridge the gap by consolidating the current knowledge and concepts in the field of HCC-related miRNAs with special emphasis on HBV and HCV. Further, we assess the potential of common as well as unique signatures that may be useful in developing novel biomarkers and therapeutics.

Noncoding RNA as therapeutic targets for hepatocellular carcinoma

Recent studies have suggested that noncoding RNAs (ncRNAs) contribute to the pathogenesis and progression of hepatocellular carcinoma (HCC). These RNA genes may be involved in various pathobiological processes such as cell proliferation, apoptosis, angiogenesis, invasion, and metastasis. Aberrant expression of ncRNA resulting from deregulated epigenetic, transcriptional, or posttranscriptional activity has been described in several studies. ncRNAs are comprised of a highly diverse group of transcripts that include microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) as well as several other types of RNA genes. Understanding the molecular mechanisms by which ncRNA contribute to hepatocarcinogenesis may enable the design of ncRNA-based therapeutics for HCC. In this review, the authors provide a perspective on therapeutic applications based on the emerging evidence of a contributory role of miRNAs and lncRNAs to the pathogenesis and progression of HCC. In addition, ncRNAs that are deregulated in expression in HCC may have utility as potential prognostic or diagnostic markers.

Association between single nucleotide polymorphisms in miRNA196a-2 and miRNA146a and susceptibility to hepatocellular carcinoma in a Chinese population

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers in the world and deeply threatens people's health, especially in China. Techniques of early diagnosis, prevention and prediction are still being discovered, among which the approaches based on single nucleotide polymorphisms in microRNA genes (miRNA SNPs) are newly proposed and show prospective potential. In particular, the association between SNPs in miRNA196a-2 (rs11614913) and miRNA146a (rs2910164) and HCC has been investigated. However, the conclusions made were conflicting, possibly due to insufficient sample size or population stratification. Further confirmations in well-designed large samples are still required. In this study, we verified the association between these two SNPs and the susceptibility to HCC by MassARRAY assay in a 2,000 large Chinese case-control sample. Significant association between rs11614913 and HCC was confirmed. Subjects with the genotype of CT+TT or T allele in rs11614913 were more resistant to HCC (CT+TT: OR (95% CI)=0.73 (0.57-0.92), P=0.01; T allele: OR (95% CI)=0.85 (0.75-0.97), P=0.02) and HBV-related HCC (CT+TT: OR (95% CI)=0.69 (0.53-0.90), P=0.01; T allele: OR (95% CI)=0.82 (0.71-0.95), P=0.01). The affected carriers of CT or TT also tended to have lower levels of serum AFP (P=0.01). This study demonstrated a role of rs11614913 in the etiology of HCC. Further research should focus on the clinical use of this miRNA SNP, so as to facilitate conquering HCC.

Associations between three common MicroRNA polymorphisms and hepatocellular carcinoma risk in Chinese

AIM

Associations between polymorphisms in miR-146aG>C, miR-196a2C>T and miR-499A>G and risk of HCC, and interaction with HBV infection in a Chinese population, were the target of the present research.

METHODS

The duplex polymerase-chain-reaction with confronting-two-pair primers (PCR-RFLP) was performed to determine the genotypes of the miR-146aG>C, miR-196a2C>T and miR-499A>G genotypes. Associations of polymorphisms with the risk of HCC were estimated by conditional logistic regression analysis.

RESULTS

Drinking, family history of cancer, HBsAg and HCV were risk factors for HCC. Multivariate regression analyses showed that subjects carrying the miR-196a2 CC genotype had significantly increased risk of HCC, with an adjusted OR (95% CI) of 2.18 (1.23-3.80). In addition, cases carrying the miR-196a2 C allele had a 1.64-fold increase in the risk for HCC (95%CI=1.03-2.49). The miR-196a CT and TT genotypes greatly significantly increased the risk of HCC in subjects with HBV infection, with adjusted ORs (95% CI) of 2.02 (1.12-3.68) and 2.69 (1.28-5.71), respectively.

CONCLUSION

Our results demonstrate that miR-196a2 CC genotype and C allele have an important role in HCC risk in Chinese, especially in patients with HBV infection.

miRNA in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. Despite improvements in HCC therapy, the prognosis for HCC patients remains poor due to a high incidence of recurrence. An improved understanding of the pathogenesis of HCC development would facilitate the development of more effective outcomes for the diagnosis and treatment of HCC at earlier stages. miRNA are small, endogenous, non-coding, ssRNA that are 21-30 nucleotides in length and modulate the expression of various target genes at the post-transcriptional and translational levels. Aberrant expression of miRNA is common in various human malignancies and modulates cancer-associated genomic regions or fragile sites. As for the relationship between miRNA and HCC, several studies have demonstrated that the aberrant expression of specific miRNA can be detected in HCC cells and tissues. However, little is known about the mechanisms of miRNA-related cell proliferation and development. In this review, we summarize the central and potential roles of miRNA in the pathogenesis of HCC and elucidate new possibilities that may be useful as diagnostic and prognostic markers, as well as novel therapeutic targets in HCC.

A functional polymorphism in microRNA-196a2 is associated with increased susceptibility to non-Hodgkin lymphoma

Aberrant expression and structural alterations of microRNAs (miRNAs) play important roles in tumorigenesis. The miRNA-196a2 polymorphism is associated with tumorigenesis, but its association with non-Hodgkin lymphoma (NHL) remains unexplored. We evaluated the association between the miRNA-196a2 T>C polymorphism (rs11614913) and NHL risk in a case-control study of 318 NHL cases and 320 healthy controls. We also examined miRNA-196a expression in tissue samples from NHL patients (n = 59). The TC and CC genotypes were associated with cancer risk in NHL [odds ratio (OR) = 1.384, confidence interval (CI) = 1.010-1.898 for TC vs. TT, and OR = 1.822, 95 % CI = 1.163-2.853 for CC vs. TT]. Analysis of the association between this polymorphism and the clinicopathology of NHL showed that the combined TC/CC genotypes were associated with Ann Arbor stage (OR = 1.852, 95 % CI = 1.139-3.010), bone marrow invasion (OR = 1.850, 95 % CI = 1.062-3.223), and B symptoms (OR = 1.852, 95 % CI =  .154-2.972), but not with immunohistological subtype, lymph node size, age, or gender. In addition, the CC or CC/TC genotypes were associated with significantly higher levels of mature miR-196a (p = 0.002 or 0.008) in a genotype-phenotype correlation analysis. Our findings suggest that the miR-196a2 polymorphism may increase the risk of NHL by altering the expression of mature miR-196a.

WITHDRAWN: Association of TNF-α-308G>A polymorphisms with hepatocellular carcinoma in Han Chinese population: A systematic review and meta-analysis

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The association of common functional polymorphisms in mir-146a and mir-196a2 and hepatocellular carcinoma risk: evidence from a meta-analysis

MicroRNAs (miRNAs) are small non-coding RNA molecules that function as tumor suppressors or oncogenes. Single nucleotide polymorphisms (SNPs) located in the miRNAs influence the function of mature miRNAs and may contribute to cancer development. Studies investigating the association between miR-146a rs2910164 and miR-196a2 rs11614913 polymorphisms and hepatocellular carcinoma (HCC) risk reported inconsistent results. We performed a meta-analysis of all available studies to summarize this situation. Eligible studies were identified by search of electronic databases including PubMed, Embase, and Cochrane library for the period up to August 2014. The association of miR-146a rs2910164 and miR-196a2 rs11614913 polymorphisms and HCC risk was assessed by odds ratios (ORs) together with their 95% confidence intervals (CIs). Finally, a total of 12 studies with 4171 cases and 4901 controls were included for miR-146a rs2910164 polymorphism and 10 studies with 4687 cases and 4990 controls were available for miR-196a2 rs11614913 polymorphism. With respect to miR-146a rs2910164 polymorphism, statistical significant increased HCC risk was found when all studies were pooled into the meta-analysis (GG+CG vs CC: OR = 1.097, 95% CI 1.005-1.197, P = 0.037). In subgroup analyses by ethnicity, source of control, and HWE in controls, significant increase of HCC risk was found in Asians, population-based studies, and studies consistent with HWE, but not in Caucasians, hospital-based studies, and studies inconsistent with HWE. With respect to miR-196a2 rs11614913 polymorphism, no significant association with HCC risk was found in the overall and subgroup analyses. The results suggest that the miR-146a rs2910164 polymorphism contributes to increased HCC susceptibility, especially in Asian populations. Further large and well-designed studies are required to validate this association.

Evaluation of a novel functional single-nucleotide polymorphism (rs35010275 G>C) in MIR196A2 promoter region as a risk factor of gastric cancer in a Chinese population

Single-nucleotide polymorphisms (SNPs) in microRNAs (miRNAs) have been suggested to influence the occurrence and progression of cancer through altering the expression and biological function of miRNAs. The aim of this study was to investigate whether the potential functional SNPs in MIR196A2 promoter had effect on the susceptibility to gastric cancer (GC) in a Chinese population.We conducted a 2-stage case-control study (753 cases and 854 controls in testing set; 940 cases and 1061 controls in validation set) to evaluate the association between 2 potential functional SNPs in MIR196A2 promoter (rs12304647 A>C and rs35010275 G>C) and GC risk. The luciferase reporter assay and electrophoretic mobility shift assay were used to examine the functionality of the important polymorphism.We found that the rs35010275 C allele was significantly associated with the decreased risk of GC (adjusted odds ratio = 0.85, 95% confidence interval = 0.77-0.94) in the combined case-control studies. The miR-196a expression levels in GC tissues were significantly higher than that in corresponding adjacent normal tissues (P < 0.001). Besides, each allele of rs35010275 displayed completely opposite effects to influence the transcription activity of MIR196A2 promoter via recruiting different transcription factors or complexes.The functional rs35010275 G>C polymorphism in MIR196A2 promoter was significantly associated with miR-196a expression and influenced the genetic susceptibility to GC.

miRNAs affect the development of hepatocellular carcinoma via dysregulation of their biogenesis and expression

The pathogenesis of hepatocellular carcinoma (HCC) is not fully understood, which has affected the early diagnosis and treatment of HCC and the survival time of patients. MicroRNAs (miRNAs) are a class of evolutionarily conserved small, non-coding RNAs, which regulate the expression of various genes post-transcriptionally. Emerging evidence indicates that the key enzymes involved in the miRNA biosynthesis pathway and some tumor-specific miRNAs are widely deregulated or upregulated in HCC and closely associated with the occurrence and development of various cancers, including HCC. Early studies have shown that miRNAs have critical roles in HCC progression by targeting many critical protein-coding genes, thereby contributing to the promotion of cell proliferation; the avoidance of apoptosis, inducing via angiogenesis; and the activation of invasion and metastasis pathways. Experimental data indicate that discovery of increasing numbers of aberrantly expressed miRNAs has opened up a new field for investigating the molecular mechanism of HCC progression. In this review, we describe the current knowledge about the roles and validated targets of miRNAs in the above pathways that are known to be hallmarks of HCC, and we also describe the influence of genetic variations in miRNA biosynthesis and genes.

Association between four common microRNA polymorphisms and the risk of hepatocellular carcinoma and HBV infection

microRNAs (miR/miRNAs) have been demonstrated to function as tumor suppressors and oncogenes, and miRNA polymorphisms may have a role in cancer development. The present study aimed to investigate the association between the miR-146aG>C, miR-149C>T, miR-196a2C>T and miR-499A>G polymorphisms and the risk of hepatocellular carcinoma (HCC) and hepatitis B virus (HBV) infection. A total of 271 patients with HCC and 532 healthy control participants were enrolled in the present study. miR-146aG>C, miR-149C>T, miR-196a2C>T and miR-499A>G polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism method. A significant difference was identified in the genotype frequency of miR-196a2C>T in the patients in the case group compared with the control group (χ²=6.88; P=0.032). Compared with the CC genotype, the miR-196a2 TT genotype was associated with a significantly reduced risk of HCC [odds ratio (OR), 0.62; 95% confidence interval (CI), 0.38–0.99], and a significantly reduced risk was also found in the dominant (OR, 0.69; 95% CI, 0.49–0.98) and recessive (OR, 0.70; 95% CI, 0.46–1.02) models. Moreover, individuals with HBV who were carrying the miR-196a2 CT and TT genotypes had a significantly reduced risk of HCC (OR, 0.62; 95% CI, 0.41–0.95; and OR, 0.39; 95% CI, 0.20–0.73, respectively). In conclusion, the present study found that the miR-196a2C>T polymorphism has a protective effect in patients with HCC, particularly in those with HBV infection.

Next generation sequencing reveals microRNA isoforms in liver cirrhosis and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents the major histological subtype of liver cancer. Tumorigenic changes in hepatic cells potentially result from aberrant expression of microRNAs (miRNAs). Individual microRNA gene may give rise to miRNAs of different length, named isomiRNAs that proved to be functionally relevant. Since microRNA length heterogeneity in hepatic tissue has not been described before, we employed next-generation sequencing to comprehensively analyze microRNA transcriptome in HCC tumors (n=24) and unaffected tissue adjacent to tumors (n=24), including samples with (n=15) and without cirrhosis (n=9). We detected 374 microRNAs expressed in liver, including miR-122-5p that constituted over 39% of the hepatic miRnome. Among the liver expressed miRs, the levels of 64 significantly differed between tumor and control samples (FDR<0.05, fold change>2). Top deregulated miRNAs included miR-1269a (T/N=22.95), miR-3144-3p (T/N=5.24), miR-183-5p (T/N=4.63), miR-10b-5p (T/N=3.87), miR-490-3p (T/N=0.13), miR-199a-5p (T/N=0.17), miR-199a-3p/miR-199b-3p (T/N=0.19), miR-214-5p (T/N=0.20) and miR-214-3p (T/N=0.21). Almost all miRNA genes produced several mature molecules differing in length (isomiRNAs). The reference sequence was not the most prevalent in 38.6% and completely absent in 10.5% of isomiRNAs. Over 26.1% of miRNAs produced isoforms carrying≥2 alternative seed regions, of which 35.5% constituted novel, previously unknown seeds. This fact sheds new light on the percentage of the human genome regulated by microRNAs and their variants. Among the most deregulated miRNAs, miR-199a-3p/miR-199b-3p (T/N fold change=0.18, FDR=0.005) was expressed in 9 isoforms with 3 different seeds, concertedly leading to upregulation of TGF-beta signaling pathway (OR=1.99; p=0.004). In conclusion, the study reveals the comprehensive miRNome of hepatic tissue and provides new tools for investigation of microRNA-dependent pathways in cirrhotic liver and hepatocellular carcinoma. This article is part of a Directed Issue entitled: Rare Cancers.

Association between miR-146aG>C and miR-196a2C>T polymorphisms and the risk of hepatocellular carcinoma in a Chinese population

MicroRNAs have been demonstrated to have a role in susceptibility and prognosis of various types of human cancer. We investigated the association between polymorphisms in miR-146aG>C, miR-196a2C>T, and miR-499A>G and hepatocellular carcinoma (HCC) risk and interaction with HCC and hepatitis B virus (HBV) infection. Two hundred sixty-six cases with HCC and 281 health controls were enrolled in the present study. Genotyping of the miR-146aG>C, miR-196a2C>T, and miR-499A>G genotypes was conducted by duplex polymerase chain reaction with the confronting two-pair primer (PCR-RFLP). Subjects with miR-146a GG and G allele had an increased risk of HCC compared with the homozygote CC genotype. Similarly, HCC patients carrying microRNA (miRNA)-196a2 computed tomography, TT, and T allele significantly decreased the risk of HCC relative to the CC genotype. Stratified analysis indicated that miR-196a2C>T polymorphism was associated with reduced risk of HBV-related HCC, but not in hepatitis C virus- and nonviral-related HCC cases. In conclusion, miR-146aG>C and miR-196a2C>T polymorphism are associated with risk of HCC patients in China, especially in patients with HBV infection. SNPs in miRNA sequences can be used as a diagnostic biomarker for HCC.

Association between two common polymorphisms and risk of hepatocellular carcinoma: evidence from an updated meta-analysis

Background. Recent studies suggested that two common polymorphisms, miR-146a G>C and miR-196a2 C>T, may be associated with individual susceptibility to hepatocellular carcinoma (HCC). However, the results remain conflicting rather than conclusive. Object. The aim of this study was to assess the association between miR-146a G>C and miR-196a2 C>T polymorphisms and the risk of HCC. Methods. A meta-analysis of 17 studies (10938 cases and 11967 controls) was performed. Odds ratios and 95% confidence intervals were used to evaluate the strength of the association. Results. For miR-146a G>C, the variant genotypes were associated with a decreased risk of HCC (CC versus GG: OR = 0.780 and 95% CI 0.700–0.869; GC/CC versus GG: OR = 0.865 and 95% CI 0.787–0.952; CC versus GC/GG: OR = 0.835 and 95% CI 0.774–0.901). For miR-196a2 C>T, significant association was also observed (TT versus CC: OR = 0.783, 95% CI: 0.649–0.943, and P = 0.010; CT versus CC: OR = 0.831, 95% CI 0.714–0.967, and P = 0.017; CT/TT versus CC: OR = 0.817, 95% CI 0.703–0.949, and P = 0.008). Conclusion. The two common polymorphisms miR-146a G>C and miR-196a2 C>T were associated with decreased HCC susceptibility, especially in Asian population.

MicroRNA sequence polymorphisms and the risk of different types of cancer

MicroRNAs (miRNAs) participate in diverse biological pathways and may act as oncogenes or tumor suppressors. Single nucleotide polymorphisms (SNPs) in miRNAs (MirSNPs) might promote carcinogenesis by affecting miRNA function and/or maturation; however, the association between MirSNPs reported and cancer risk remain inconsistent. Here, we investigated the association between nine common MirSNPs and cancer risk using data from large scale case-control studies. Eight precursor-miRNA (pre-miRNA) SNPs (rs2043556/miR-605, rs3746444/miR-499a/b, rs4919510/miR-608, rs2910164/miR-146a, rs11614913/miR-196a2, rs895819/miR-27a, rs2292832/miR-149, rs6505162/miR-423) and one primary-miRNA (pri-miRNA) SNP (rs1834306/miR-100) were analyzed in 16399 cases and 21779 controls from seven published studies in eight common cancers. With a novel statistic, Cross phenotype meta-analysis (CPMA) of the association of MirSNPs with multiple phenotypes indicated rs2910164 C (P = 1.11E-03), rs2043556 C (P = 0.0165), rs6505162 C (P = 2.05E-03) and rs895819 (P = 0.0284) were associated with a significant overall risk of cancer. In conclusion, MirSNPs might affect an individual's susceptibility to various types of cancer.

Effects of common polymorphisms rs2910164 in miR-146a and rs11614913 in miR-196a2 on susceptibility to colorectal cancer: a systematic review meta-analysis

PURPOSE

Emerging evidence has shown that single nucleotide polymorphisms occurred in microRNAs may contribute to the development of colorectal cancer (CRC). rs2910164 in miR-146a and rs11614913 in miR-196a2 are suggested to be associated with the susceptibility to CRC, but individually published studies revealed inconclusive results. To systematically summarize the possible correlationship between these polymorphisms and CRC risk, we performed this meta-analysis.

METHODS

We retrieved the relevant articles of the associations between these two microRNA polymorphisms and susceptibility to CRC for the period up to July 1, 2013. A total of seven articles were identified with 2,143 cases and 2,457 controls for miR-146a rs2910164, 1,594 cases and 2,252 controls for miR-196a2 rs11614913. Odds ratio and 95 % confidence interval were calculated to investigate the strength of the association.

RESULTS

The pooled analysis showed that miR-146a rs2910164 did not reveal any correlation with CRC susceptibility. However, a decreased risk was observed between miR-196a2 rs11614913 and CRC in all genetic models.

CONCLUSION

Our current meta-analysis demonstrates that miR-196a2 rs11614913 most likely contributes to decreased risk of CRC, whereas miR-146a rs2910164 may not be associated with the susceptibility to CRC.

New insights on the role of epigenetic alterations in hepatocellular carcinoma

Emerging evidence assigns to epigenetic mechanisms heritable differences in gene function that come into being during cell development or via the effect of environmental factors. Epigenetic deregulation is strongly involved in the development of hepatocellular carcinoma (HCC). It includes changes in methionine metabolism, promoter hypermethylation, or increased proteasomal degradation of oncosuppressors, as well as posttranscriptional deregulation by microRNA or messenger RNA (mRNA) binding proteins. Alterations in the methylation of the promoter of methyl adenosyltransferase MAT1A and MAT2A genes in HCC result in decreased S-adenosylmethionine levels, global DNA hypomethylation, and deregulation of signal transduction pathways linked to methionine metabolism and methyl adenosyltransferases activity. Changes in S-adenosylmethionine levels may also depend on MAT1A mRNA destabilization associated with MAT2A mRNA stabilization by specific proteins. Decrease in MAT1A expression has also been attributed to miRNA upregulation in HCC. A complex deregulation of miRNAs is also strongly involved in hepatocarcinogenesis, with up-regulation of different miRNAs targeting oncosuppressor genes and down-regulation of miRNAs targeting genes involved in cell-cycle and signal transduction control. Oncosuppressor gene down-regulation in HCC is also induced by promoter hypermethylation or posttranslational deregulation, leading to proteasomal degradation. The role of epigenetic changes in hepatocarcinogenesis has recently suggested new promising therapeutic approaches for HCC on the basis of the administration of methylating agents, inhibition of methyl adenosyltransferases, and restoration of the expression of tumor-suppressor miRNAs.

Hsa-miR-196a2 functional SNP is associated with the risk of ESCC in individuals under 60 years old

BACKGROUND AND AIM

The miR-196a2 gene contains a C/T polymorphism (rs11614913). Its presence could change the conformation of secondary structure of miR-196a2 RNA, and directly affect the binding to target mRNAs and the miRNA maturation process. Both of which eventually alter protein expression and contributed to cancer susceptibility. This study assessed whether the rs11614913 single nucleotide polymorphism (SNP) could affect an individual's susceptibility to esophageal squamous cell carcinomas (ESCC).

METHODS

SNP rs11614913 was genotyped by polymerase chain reaction ligase detection reaction (PCR-LDR) in 597 ESCC patients and 597 control subjects.

RESULTS

Overall, there were no significant differences in the frequency of the miRNA-196a2 SNP rs11614913 genotype between the ESCC cases and the controls (χ(2) = 1.395, p = 0.498). The TT genotype, CT genotype and CT/TT combined genotype (dominant model) did not modify the risk of ESCC as compared with the CC genotype. Comparisons of the TT genotype to the CT/CC combined genotype did not reveal a significant association to ESCC, too. However, further analyses revealed an increased risk of ESCC in the dominant model (OR = 1.56, 95% CI = 1.08-2.26) and the allele frequency comparison (OR = 1.31, 95% CI = 1.06-1.63) in the ≤60-year-old group.

CONCLUSIONS

These results suggest that the miRNA-196a2 functional polymorphism rs11614913 might be an effective genetic marker for ESCC risk assessment in individuals younger than 60 years of age from a region of high ESCC incidence in northern China.

Association between microRNA polymorphisms and cancer risk based on the findings of 66 case-control studies

MicroRNAs (miRNAs) are small non-coding RNA molecules, which participate in diverse biological processes and may regulate tumor suppressor genes or oncogenes. Single nucleotide polymorphisms (SNPs) in miRNA may contribute to diverse functional consequences, including cancer development, by altering miRNA expression. Numerous studies have shown the association between miRNA SNPs and cancer risk; however, the results are generally debatable and inconclusive, mainly due to limited statistical power. To assess the relationship between the five most common SNPs (miR-146a rs2910164, miR-196a2 rs11614913, miR-499 rs3746444, miR-149 rs2292832, and miR-27a rs895919) and the risk cancer development, we performed a meta-analysis of 66 published case-control studies. Crude odds ratios at 95% confidence intervals were used to investigate the strength of the association. No association was observed between rs2910164 and cancer risk in the overall group. However, in stratified analysis, we found that either the rs2910164 C allele or the CC genotype was protective against bladder cancer, prostate cancer, cervical cancer, and colorectal cancer, whereas it was a risk factor for papillary thyroid carcinoma and squamous cell carcinoma of the head and neck (SCCHN). Further, rs11614913 was found to be significantly associated with decreased cancer risk, in particular, for bladder cancer, gastric cancer, and SCCHN. For miR-499, a significant association was found between the rs3746444 polymorphism and cancer risk in pooled analysis. In subgroup analysis, similar results were mainly observed for breast cancer. Finally, no association was found between rs2292832 and rs895919 polymorphisms and cancer risk in the overall group and in stratified analysis. In summary, miR-196a2 rs11614913, miR-146a rs2910164, and miR-499 rs3746444 are risk factors for cancer development, whereas mir-149 rs2292832 and miR-27a rs895919 are not associated with cancer risk.

MicroRNA-196A-2 polymorphisms and hepatocellular carcinoma in patients with chronic hepatitis B

Single nucleotide polymorphisms (SNPs) in microRNA (miR)-196a-2 have been suggested to contribute to susceptibility to various human cancers. The aim of this study was to determine whether polymorphisms of miRNA-196a-2 affect the clinical outcomes of hepatitis B virus (HBV) infection in Korean patients. Genotyping was performed for 1,439 Korean patients with either past or present HBV infection, including 404 control subjects who underwent spontaneous recovery and 1,035 subjects with chronic HBV (313 cases of chronic hepatitis B, 305 cases of cirrhosis of the liver, and 417 cases of hepatocellular carcinoma [HCC]). Genotyping results revealed that the polymorphism rs12304647A>C, which lies in the pri-miRNA region of miR-196a-2, has a significant minor allele frequency (0.210). Logistic analysis revealed that the rs12304647A>C SNP was associated with a significant protective effect against HCC in patients with chronic hepatitis (odds ratio [OR] = 0.70, P = 0.005 in a codominant model; OR = 0.73, P = 0.03 in a dominant model; OR = 0.31, P = 0.004 in a recessive model), and in the patients with cirrhosis (OR = 0.63, P = 0.0009 in a codominant model; OR = 0.66, P = 0.01 in a dominant model; OR = 0.25, P = 0.001 in a recessive model). A Cox relative hazards model with adjustments for age, gender, HBeAg status, and cirrhosis revealed that rs12304647A>C retained its association with HCC in a codominant model (relative hazards [RH] = 1.14, P = 0.05) and in a recessive model (RH = 1.44, P = 0.03). However, the miR-196a-2 rs12304647A>C SNP had no association with HBV clearance. In conclusion, the miR-196a-2 rs12304647 CC genotype had a protective effect against development of HCC in comparison to the AA or AC genotypes in patients with chronic hepatitis and cirrhosis.

MicroRNA-related sequence variations in human cancers

MicroRNAs are emerging as a most promising field in basic and translational research, explaining the pathogenesis of numerous human diseases and providing excellent tools for their management. This review considers the effects of microRNA sequence variations and their implication in pathogenesis and predisposition to human cancers. Although the role of microRNAs still remains to be elucidated, functional, and populational studies indicate that microRNA variants are important factors underlying the process of carcinogenesis. Further understanding of the cellular and molecular basis of microRNA action will lead to the identification of their new target genes and microRNA-regulated pathways. As a consequence, novel models of cancer pathogenesis can be proposed, and serve as a basis for elucidation of new prognostic and diagnostic tools for human cancers.

The associations of single nucleotide polymorphisms in miR-146a, miR-196a and miR-499 with breast cancer susceptibility

Background

Previous studies have investigated the association between single nucleotide polymorphisms (SNPs) located in microRNAs (miRNAs) and breast cancer susceptibility; however, because of their limited statistical power, many discrepancies are revealed in these studies. The meta-analysis presented here aimed to identify and characterize the roles of miRNA SNPs in breast cancer risk, and evaluate the associations of polymorphisms in miR-146a rs2910164, miR-196a rs11614913 and miR-499 rs3746444 with breast cancer susceptibility, respectively.

Methodology/Principal Findings

The PubMed and Embases databases were searched updated to 31^st December, 2012. The complete data of polymorphisms in miR-146a rs2910164, miR-196a rs11614913 and miR-499 rs3746444 from case-control studies for breast cancer were analyzed by odds ratios (ORs) with 95% confidence intervals (CIs) to reveal the associations of SNPs in miRNAs with breast cancer susceptibility. Totally, six studies for rs2910164 in miR-146a, involving 4225 cases and 4469 controls; eight studies for rs11614913 in miR-196a, involving 4110 cases and 5100 controls; and three studies of rs3746444 in miR-499, involving 2588 cases and 3260 controls, were investigated in the meta-analysis. The rs11614913 (TT+CT) genotype of miR-196a2 was revealed to be associated with a decreased breast cancer susceptibility compared with the CC genotypes (OR = 0.906, 95% CI: 0.825–0.995, P = 0.039); however, no significant associations were observed between rs2910164 in miR-146a (or rs3746444 in miR-499) and breast cancer susceptibility.

Conclusions

This meta-analysis demonstrates the compelling evidence that the rs11614913 CC genotype in miR-196a2 increases breast cancer risk, which provides useful information for the early diagnosis and prevention of breast cancer.

Three common functional polymorphisms in microRNA encoding genes in the susceptibility to hepatocellular carcinoma: a systematic review and meta-analysis

Emerging evidences have shown that common genetic polymorphisms in microRNAs may be associated with the development of hepatocellular carcinoma (HCC); but individually published studies and previous meta-analyses revealed inconclusive results. The aims of this review and meta-analysis are to assess whether common single-nucleotide polymorphisms (SNPs) in the genes encoding the microRNAs are associated with susceptibility to HCC development and clinicopathologic characteristics of hepatitis B virus (HBV) related HCC. A computerized search was performed in PubMed, Embase, Web of Science and China BioMedicine (CBM) databases to identify relevant articles published before January 1st 2013. Ten case-control studies were assessed with a total of 3437 cases and 3437 healthy controls. Three common functional SNPs in miRNA-encoding genes were found, including miR-146a G>C (rs2910164), miR-196a-2 C>T (rs11614913) and miR-499 T>C (rs3746444). This meta-analysis revealed that the miR-146a C variant was associated with a decrease in HCC risk, especially among Asian and male populations; while the miR-196a-2 T variant was associated with susceptibility to HCC among Caucasian populations. However, we failed to find any significant correlations between the miR-499 C polymorphism and HCC risks. When further stratification on HBV status was conducted, a similar trend of association between the three SNPs and the HBV-related HCC risks was observed, but these results were not statistically significant due to small sample sizes. The current meta-analysis demonstrates that SNPs contained in the genes encoding miR-146a and miR-196a-2 may play a major role in genetic susceptibility to HCC.

Different effects of three polymorphisms in MicroRNAs on cancer risk in Asian population: evidence from published literatures

MicroRNAs (miRNAs) are a class of small non-protein-coding RNAs, which have emerged as integrated and important post-transcriptional regulators of gene expression. It has been demonstrated that single nucleotide polymorphisms (SNPs) exist in protein-coding genes. Accumulated studies have evaluated the association of miRNA SNPs with cancer risk, especially in Asian population, which included a series of related studies. However, the results remain controversial for the different genetic backgrounds, living habits and environment exposed. To evaluate the relationship between SNPs in miRNAs and cancer risk, 21 studies focused on Asian population were enrolled for the pooled analysis for three polymorphisms rs2910164, rs11614913, rs3746444 in three miRNAs miR-146aG>C, miR-196a2C>T, miR-499A>G using odds ratios (ORs) with 95% confidence intervals (CIs). For rs2910164 polymorphism, C allele was observed association with decreased overall cancer risk. In addition, subgroup analysis revealed of rs2910164 C allele decreased hepatocellular carcinoma (HCC), cervical cancer and prostate cancer risk among Chinese population. For rs11614913 polymorphism, TT genotype was observed to be associated with decreased cancer risk, especially for cancer type of colorectal cancer (CRC), lung cancer and country of Korea, North India. Whereas, rs3746444 G allele was an increased cancer risk factor in Chinese population, especially for breast cancer. In conclusion, this meta-analysis indicated that rs2910164 C allele was associated with decreased cancer risk in Chinese population. However, the association varied from different cancer types. Furthermore, TT genotype of rs11614913 was associated with decreased cancer risk. While different cancer types and countries contributed to different effects. Whereas, rs3746444 G allele was a risk factor in Chinese population, and the association varied from different cancer types.

Meta-Analysis of the Association between Mir-196a-2 Polymorphism and Cancer Susceptibility

Objective

MicroRNA plays a vital role in gene expression, and microRNA dysregulation is involved in carcinogenesis. The miR-196a-2 polymorphism rs11614913 is reportedly associated with cancer susceptibility. This meta-analysis was performed to assess the overall association of miR-196a-2 with cancer risk.

Methods

A total of 27 independent case-control studies involving 10,435 cases and 12,075 controls were analyzed for the rs11614913 polymorphism.

Results

A significant association was found between rs11614913 polymorphism and cancer risk in four genetic models (CT vs. TT, OR=1.15, 95%CI=1.05–1.27; CC vs. TT, OR=1.23, 95%CI=1.08–1.39; Dominant model, OR=1.17, 95%CI=1.06–1.30; Additive model, OR=1.08, 95%CI=1.01–1.14). In the subgroup analysis of different tumor types, the C allele was associated with increased risk of lung, breast, and colorectal cancer, but not with liver, gastric, or esophageal cancer. In the subgroup analysis by ethnicity, a significantly increased risk of cancer was found among Asians in all genetic models, but no associations were found in the Caucasian subgroup.

Conclusions

The meta-analysis demonstrated that the miR-196a-2 polymorphism is associated with cancer susceptibility, especially lung cancer, colorectal cancer, and breast cancer among Asian populations.

Genetic variants in pseudogene E2F3P1 confer risk for HBV-related hepatocellular carcinoma in a Chinese population

Recent studies showed that pseudogenes can regulate the expression of their coding gene partners by competing for miRNAs. The E2F family plays a crucial role in the control of cell cycle checkpoint. E2F3P1 is a pseudogene of E2F3. Few studies focused on genetic variations on pseudogenes. In this study, we performed a case-control study to assess the association between single nucleotide polymorphisms (SNPs) in E2F3P1 and hepatocellular carcinoma (HCC) risk in 1050 hepatitis B virus (HBV)-positive HCC cases and 1050 chronic HBV carriers. Logistic regression analysis was applied to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between genotypes and HCC risk. We found that the variant CT/TT genotypes of rs1838149 were associated with a significantly decreased risk of HCC (adjusted OR = 0.66, 95% CIs = 0.51-0.86, P = 0.002) compared to those with wildtype CC homozygote. Furthermore, the AA genotype of rs9909601 had an increased HCC risk with an adjusted OR of 1.41 (95% CIs = 1.07-1.86), and the A allele of rs9909601 was significantly associated with HCC risk compared to those with the G allele (adjusted OR = 1.17, 95% CIs = 1.03-1.33, P = 0.017). These results indicate that genetic variations in the pseudogene E2F3P1 may confer HCC risk.