The role of matrix metalloproteinase-2 and miR-196a2 in bronchial asthma pathogenesis and diagnosis

Background

Bronchial asthma is a persistent inflammatory respiratory condition that restricts the passage of air and causes hyperresponsiveness. Chronic asthma can be classified into three categories: mild, moderate, and severe. Remodeling took place as the extracellular matrix accumulated in the walls of the airways. Inflammation occurs as a result of the damage caused by matrix metalloproteinase-2 (MMP-2) to basement membrane type IV collagen. The severity of asthma may be associated with miR-196a2. The objective of our study was to investigate the underlying mechanisms and clinical relevance of miR-196a2 and MMP-2 serum levels in relation to the severity of asthma.

Methods

This study recruited 85 controls and 95 asthmatics classified as mild, moderate, or severe. Expression of miR-196a2 was measured by quantitative reverse transcriptase PCR. Using the enzyme-linked immunosorbent assay (ELISA), MMP-2, IL-6, and total immunoglobulin E (IgE) levels in the serum of asthmatics of various grades were compared to a control group. MMP-2's diagnostic and prognostic potential was determined using ROC curve analysis. This study also measured blood Eosinophils and PFTs. We examined MMP-2's connections with IgE, blood Eosinophils, and PFTs.

Results

The current investigation found that miR-196a2 expression was significantly higher in the control group than in asthmatic patients as a whole. The study found that severe asthmatics had higher MMP-2, IL-6, and IgE serum levels than healthy controls. We identified the MMP-2 serum concentration cutoff with great sensitivity and specificity. Significant relationships between MMP-2 serum level and miR-196a2 expression in the patient group with severe asthmatics were found. The MMP-2, IL-6, and IgE serum levels were considerably higher in mild, moderate, and severe asthmatics than controls. The miR-196a2 expression and MMP-2 serum concentration correlated positively with IgE and blood eosinophils % and negatively with all lung function tests in the asthmatic patient group.Conclusion: the study revealed that the elevated miR-196a2 expression and serum concentration of MMP-2, IL-6, and IgE associated with elevated blood eosinophils % is associated with pathophysiology and degree of asthma severity. The miR-196a2 expression and MMP-2 serum concentration have a promising diagnostic and prognostic ability in bronchial asthma.

Functional Variants in MicroRNAs (rs895819, rs11614913 and rs2910164) Are Associated with Susceptibility and Clinicopathological Features in Mexican Patients with Colorectal Cancer

BACKGROUND

miRNAs are non-coding RNAs participating actively in the post-translational regulation of oncogenes, tumor suppressor, and DNA repair genes implicated in colorectal cancer (CRC). This study aims to examine the association of the variants miR-27a (rs895819 A>G), miR-196a2 (rs11614913 T>G) and miR-146a (rs2910164 C>G) in Mexican CRC patients.

METHODS

DNA samples from 183 patients and 186 healthy Mexican subjects were analyzed. Variants were identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methodology. Association was calculated by the odds ratio (OR) and adjusted by the Bonferroni test.

RESULTS

Patients carrying the G/G genotype of the rs895819 variant in the miR-27a gene showed an increased risk of CRC (19% vs 12%, P=0.013). A similar tendency was noticed for patients younger than 50 years carrying A/G (48% vs 41%, P=0.014). The A/G genotype in TNM stages I+II (55.7% vs 40.8%, P=0.011) and tumor location in the colon (69.5 vs 40.8%, P=0.001) were also increased. For the variant rs11614913 of the miR-196a2 gene, carriers of the C/C genotype showed an increased risk of CRC (32% vs 22%, P=0.009). This genotype was more frequent in TNM stage III+IV (36.8% vs 22.5%, P=0.007) and the tumor had a more recurrent location in the rectum (31.6% vs 22.5%, P=0.013). The rs2910164 variant of the miR-146a gene was found to have no significant risk associations.

CONCLUSION

Our results reveal that the rs895819 variant in miR-27a and rs11614913 in miR-196a2 have a substantial impact on the development of CRC.

Association between Genetic Polymorphisms in MicroRNAs 196a2 (rs11614913) and 34 b/c (rs4938723) and Risk of Hepatocellular Carcinoma in Egyptian Patients

BACKGROUND

Hepatocellular carcinoma (HCC) is a common cancer with substantial cancer-related deaths worldwide. Deregulation of some genetic polymorphisms has been identified in HCC.

OBJECTIVE

We aimed to demonstrate the frequency of miRNA 196a2 rs11614913 and miRNA 34 b/c rs4938723 gene polymorphisms in HCC patients and their correlation with the clinical features and laboratory findings at diagnosis.

SUBJECTS AND METHODS

The study was performed on 40 patients with newly diagnosed HCC and 40 patients with liver cirrhosis in addition to 40 age and sex-matched healthy controls. Detection of miRNA 196a2 rs11614913 and miRNA 34 b/c rs4938723 gene polymorphisms was determined by PCR-RFLP.

RESULTS

HCC patients had significantly higher frequency of miR-196-2a rs11614913 CC genotype when compared with cirrhotic patients (60.0 % versus 30.0 %, p=0.013). In spite of the fact that HCC patients also had higher frequency of miR-196-2a rs11614913 CC genotype in comparison to controls, the difference fell short of statistical significance (60.0 % versus 42.5 %, p=0.18). No significant differences were found between the studied groups regarding the frequency of miR-196-2a alleles. miR34 b/c rs4938723 CC genotype was the only identified genotype in all participants in the three studied groups. No significant associations were found between the different clinical and laboratory variables and genotypic variations in HCC patients.

CONCLUSIONS

This study identified miR-196a2 rs11614913 CC genotype as a risk factor for HCC development while we failed to document similar relation for miR-34b/c rs4938723 polymorphism.

The miRNA 196a2 rs11614913 variant has prognostic impact on Turkish patients with multiple myeloma

Objective

Multiple myeloma (MM) arises from malignant plasma cells as a single clone in the bone marrow. Accumulating evidences have reported that there is an association between miR-196a2 (rs11614913) variant and various cancers while there were unverified and inconsistent results in MM. The goal of this study is to investigate the impact of the miR-196a2 variant on clinical findings and susceptibility in MM. Two hundred MM patients (156 patients under transplantation of autologous stem cell) and 200 healthy controls included in this study.

Results

The statistical analysis showed no significant relationship for allele and frequencies of miR-196a2 genotype between patients and controls (p > 0.05). Log-rank test showed that gender has highly significant impact on both OS and PFS (p = 0.027, p = 0.045). In the univariate analysis, TT genotype (p = 0.022), and CT/TT (p = 0.008) had better OS. In the multivariate analysis, CC/CT-TT were associated with positively OS (p = 0.041). Currently, the most valuable prognostic markers in MM that has clinical implication are genetic abnormalities. It can be concluded from the results that miR-1962a variant is effective in prognosis of the MM. It is believed that these findings will help us understand the molecular basis of disease.

Evaluation of miR-196a2 expression and Annexin A1 level in children with bronchial asthmaEvaluation of miR-196a2 expression and Annexin A1 level in children

BACKGROUND

Annexin A1 (ANXA1) is an important anti-inflammatory mediator that may play a significant role in bronchial asthma. MiR-196a2 can target ANXA1 and therefore may play a role in the pathogenesis of asthma.

AIM OF STUDY

This is the first study which aimed to evaluate the expression of miR-196a2 in the serum of asthmatic children and correlate its expression with ANXA1 serum level and asthma severity.

SUBJECTS AND METHODS

The study included 100 asthma patients who were subdivided into three groups (mild, moderate and severe) and 50 healthy control subjects. Assessment of miR-196a2 expression and ANXA1 serum level were done using quantitative reverse transcriptase PCR (RT qPCR) and Elisa techniques, respectively.

RESULTS

Compared to the control group, asthmatic children showed an increased ANXA1 serum level and decreased expression of miR-196a2 (p=0.001). However, ANXA1 serum level was lower and miR-196a2 expression was higher in severe asthmatic patients compared to moderate asthmatic ones (p=0.01, 0.03). Pearson's correlation coefficient revealed no significant correlations between ANXA1 serum level and miR-196a2 expression in the patient group (p=0.9).

CONCLUSIONS

Altered miR-196a2 expression and serum ANXA1 concentration may play a role in the pathogenesis of asthma. In addition, ANXA1 and miR-196a2 may represent potential diagnostic biomarkers for asthma and future targets for therapy.

Micro-RNA 196a2 expression and miR-196a2 (rs11614913) polymorphism in T1DM: a pilot study

Background Recent emerging evidence supports the role of miR-196a2 in various human diseases. However, its role in type 1 diabetes mellitus (T1DM) is still underestimated. We aimed, for the first time, to investigate the expression of miR-196a2 in T1DM and the association of miR-196a2 (rs11614913) polymorphism with susceptibility of T1DM in a sample of patients from Cairo, Egypt. Methods The study included 150 patients and 150 healthy subjects. Evaluation of rs11614913 genotypes and miR-196a2 expression was done using the allelic discrimination and quantitative reverse transcriptase polymerase chain reaction (PCR) method, respectively. Results The Hardy-Weinberg equilibrium of single nucleotide polymorphism(SNP) was detected among controls (p = 0.2). Our results revealed that the TT genotype was more frequent in patients (22.6%) than controls (10%) while the CC genotype was more frequent in controls (47.3%) than patients (39.3%) (p = 0.01). The frequency of the T allele was significantly higher in patients than in controls (41.7 vs. 31.3%), while the C allele was more frequent in controls (p = 0.008). After adjustment for traditional risk factors, the association of the TT genotype with T1DM remained significant (TT vs. CC, odds ration [OR] = 3.2, 95% confidence interval [CI]: 1.4-7.4, p = 0.005). Power analysis of the data yielded a statistical power of 80% for the miR-196a2 rs11614913 with T1DM. Relative expression of miR-196a2 showed significant decrease in patients compared to controls (median = 0.09, 0.5, interquartile range [IQR] = 0.03-1.6, 0.1-2.1). However, miR-196a2 expression showed no significant difference between different rs11614913 genotypes (p = 0.5). Conclusions Our findings demonstrated that miR-196a rs11614913 is associated with T1DM and decreased expression of miR-196a2 may play a role in pathogenesis of T1DM.

Association Between MicroRNAs Polymorphisms and Risk of Ischemic Stroke: A Meta-Analysis in Chinese Individuals

Objective: Previous studies have demonstrated that some single-nucleotide polymorphisms (SNPs) in miRNAs are related to the risk of ischemic stroke (IS), but the conclusions are still controversial and inconclusive. We performed this meta-analysis to further assess the association between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), miR-499 A>G (rs3746444) and risk of IS in Chinese individuals. Methods: Relevant studies were identified in the databases of PubMed, Embase. The strength of correlation between microRNAs polymorphisms and IS risk was assessed by odds ratios (ORs) and 95% confidence intervals (95% CIs) under five genetic models. Results: 5 studies, containing 2,632 cases and 3,191 controls, were included in this meta-analysis. The overall results of meta-analysis indicated that there were no significant association between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), and the IS risk in the overall analyses. MiR-499 A>G (rs3746444) was associated with an increased IS risk under allele model (OR = 1.30, 95% CI = 1.02-1.66), heterozygous model (OR = 1.35, 95% CI = 1.01-1.79) and dominant model (OR = 1.36, 95% CI = 1.02-1.80) in Chinese. The sensitivity analysis results of these four polymorphisms were similar to the overall results. Conclusion: MiR-499 A>G (rs3746444) G allele and AG, AG + AA genotype might be risk factors of IS in Chinese. No significant association was observed between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), and IS risk. The associations may be different due to geographical factors of China. More explorations in more diverse geographically regions with large sample size are expected to further verify the findings in the future.

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.

The association between two common polymorphisms (miR-146a rs2910164 and miR-196a2 rs11614913) and susceptibility to gastric cancer: A meta-analysis

BACKGROUND

Accumulating evidence has demonstrated that single nucleotide polymorphisms (SNPs) in microRNAs (miR-146a rs2910164 and miR-196a2 rs11614913) might be connected with the risk of gastric cancer (GC). However, the studies are controversial and inconclusive. We performed this meta-analysis to assess the potential association between two SNPs and susceptibility to GC systematically and comprehensively.

METHODS

Through a systematic literature search, eight case-control studies for rs2910164 and seven case-control studies for rs11614913 were identified and included in this meta-analysis. The odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to investigate the association between the two SNPs and the GC risk. Additionally, a subgroup analysis and a publication bias test were performed.

RESULTS

Our results showed that the only significant association between the miR-146a rs2910164 polymorphism and susceptibility to gastric cancer was found in the heterozygous model (OR = 0.884, 95% CI: 0.795-0.983, Ph= 0.326, P = 0.022). Similarly, when stratified by ethnicity, there was an obvious correlation in the heterozygous model (OR = 0.734, 95% CI: 0.542-0.993, Ph = 0.441, P = 0.045) in Caucasians but not in Asians. For miR-196a2, this meta-analysis suggested that neither the allele frequency nor the genotype distribution of the polymorphism was associated with GC risk in the five genetic models. Similarly, the subgroup analysis by ethnicity showed no association with susceptibility to GC.

CONCLUSION

Our studies suggested that the miR-146a rs2910164 polymorphism might marginally contribute to a decreased risk of gastric cancer, especially in Caucasians, whereas the miR-196a2 rs11614913 polymorphism might not be associated with susceptibility to GC.

A passenger strand variant in miR-196a2 contributes to asthma severity in children and adolescents: A preliminary study

There is emerging evidence to support the role of microRNAs in allergic airway diseases and inflammation. Genetic variants in microRNA genes might affect microRNA-mediated cell regulation. This preliminary study was designed to investigate the association of the microRNA-196a2 rs11614913 (C/T) polymorphism with susceptibility to asthma and clinical outcomes in children and adolescents. Genotyping of rs11614913 polymorphism was determined in 96 patients with bronchial asthma (6-18 years of age) and 96 unrelated controls, using real-time polymerase chain reaction technology. In-silico target prediction and network core analyses were performed. The asthmatics did not show significant differences in genotype distribution (p = 0.609) and allele frequencies (p = 0.428) compared with the controls. There were also no associations with disease duration, age at onset, asthma phenotype, asthma control, therapeutic level, airway hyper-responsiveness, or biochemical parameters in the blood. However, the CC genotype was associated with a more severe degree of asthma (p = 0. 023) and higher frequency of nocturnal asthma (p = 0.002). Carriers for CC were 17 times more likely to develop nocturnal asthma, and had a more than 2.5-fold increased risk for poor disease outcome compared with CT and TT individuals. In conclusion, microRNA-196a2 rs11614913 polymorphism might be associated with asthma severity in our sample of the Egyptian population. Further investigations in studies with a larger sample size and functional tests are needed to validate our findings and to explore the detailed biological mechanisms.

Association between single nucleotide polymorphism in miR-499, miR-196a2, miR-146a and miR-149 and prostate cancer risk in a sample of Iranian population

MicroRNAs (miRNAs) play an important role in regulating gene expression at the post-transcriptional level and are involved in numerous physiological processes. Accumulating evidence suggests that single-nucleotide polymorphisms (SNPs) in human miRNA genes may affect miRNA biogenesis pathway and influence the susceptibility to several diseases such as cancer. The present study aimed to evaluate the impact of miR-499 rs3746444, miR-196a2 rs11614913, miR-149 rs2292832, and miR-146a rs2910164 polymorphisms on prostate cancer (PCa) risk in a sample of Iranian population. This case-control study was done on 169 patients with pathologically confirmed PCa and 182 benign prostatic hyperplasia (BPH). The genotyping assays were done using T-ARMS-PCR or PCR-RFLP methods. The findings indicated that CC genotype of miR-499 rs3746444 polymorphism increased the risk of PCa (OR = 1.76, 95% CI = 1.12-2.79, P = 0.019) compared to TT genotype. No statistically significant association was found between miR-196a2 rs11614913, miR-149 rs2292832, and miR-146a rs2910164 polymorphisms and PCa risk. In summary, the findings indicated that miR-499 rs3746444 polymorphism increased the risk of PCa in an Iranian population. Further studies with larger sample sizes and different ethnicities are necessary to verify the findings of the present study.

A Meta-Analysis of the Association between Polymorphisms in MicroRNAs and Risk of Ischemic Stroke

Ischemic stroke (IS) is responsible for a high death rate and for adult disability worldwide. MiR-146a (rs2910164), miR-149 (rs2292832), miR-196a2 (rs11614913) and miR-499 (rs3746444) are found to be associated with ischemic stroke. However, the results were inconsistent and inconclusive. The present study performed a meta-analysis to get a more precise and comprehensive estimation of the association between the four polymorphisms and IS risk. The databases Pubmed, Embase, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, and Chinese Biomedical Literature Database were searched for related studies. A total of five studies including 2230 cases and 2229 controls were identified for the meta-analysis. The results indicate that TT genotype and T allele of miR-149 (rs2292832) are associated with significantly lower risks of IS in a homozygous model (OR = 0.70) and an allelic model (OR = 0.86). No significant associations were found between miR-146a (rs2910164), miR-196a2 (rs11614913), miR-499 (3746444) and IS susceptibility in any of the studies. However, subgroup analysis by sample size indicates a significant decrease in risks of IS for CC genotype and C allele of miR-146a (rs2910164) in the large sample size group. Therefore, miR-149 (rs2292832) might be recommended as a predictor for IS risk, while miR-146a (rs2910164), miR-196a2 (rs11614913), miR-499 (3746444) are not.

Genetic variants in miR-196a2 and miR-499 are associated with susceptibility to esophageal squamous cell carcinoma in Chinese Han population

Esophageal squamous cell carcinoma (ESCC) is the dominant type of esophageal cancer in the East Asian population. MicroRNAs (miRNAs) have been studied to play important roles in tumorigenesis. Single nucleotide polymorphisms (SNPs) in miRNA lead to the aberrant expression and structural alteration of miRNA and are hypothesized to be involved in tumorigenesis and cancer development. We conducted a population-based case-control study to evaluate the association between SNPs in miRNAs and ESCC risk in 1400 ESCC cases and 2185 matched controls. Four SNPs including miR-196a2 rs11614913, miR-146a rs2910164, miR-499 rs3746444, and miR-423 rs6505162 were selected with comprehensive collection strategy and genotyped using the SNaPshot Multiplex System. Odds ratio (OR) and 95 % confidence interval (95 % CI) were used to assess the strength of association. The CC genotype of miR-196a2 rs11614913 was significantly associated with an increased ESCC risk compared with the TT genotype (OR 1.11, 95 % CI 1.01-1.22, P 0.049) and the TT/TC genotypes (OR 1.09, 95 % CI 1.01-1.19, P 0.043). The association was more pronounced in non-drinkers in the recessive model (OR 1.13, 95 % CI 1.01-1.27, P 0.029). A significantly increased risk of ESCC associated with miR-499 rs3746444 polymorphism was evident among patients who never smoking and drinking. This study suggests that miR-196a2 rs11614913 and miR-499 rs3746444 are associated with an increased ESCC risk in a Chinese population.

Assessment of association between genetic variants in microRNA genes hsa-miR-499, hsa-miR-196a2 and hsa-miR-27a and prostate cancer risk in Serbian population

Due to their potentially functional significance, genetic variants within microRNA genes have been recognized as candidates for cancer-related genetic biomarkers. Among the most extensively studied so far are rs3746444, rs11614913 and rs895819. Nevertheless, only few previous studies in Asian population analyzed the association of rs3746444 and rs11614913 with prostate cancer (PCa) risk, while rs895819 was not evaluated in relation to this issue. The aim of this study was to assess the possible association between these genetic variants and PCa risk and progression in Serbian population. 355 samples of peripheral blood were obtained from the patients with PCa and 353 samples from patients with benign prostatic hyperplasia (BPH). 312 volunteers derived from general population who gave samples of buccal swabs were included in the control group. Genotyping of rs3746444, rs11614913 and rs895819 was performed by using PCR-RFLP method, HRM analysis and allele-specific PCR, respectively. Allelic and genotypic associations were evaluated by unconditional linear (for serum PSA level in PCa patients) and logistic regression method with adjustment for age. Minor allele C of rs895819 was found to be associated with the increased risk of developing PCa under dominant (P=0.035; OR=1.38, 95%CI 1.02-1.86) and overdominant (P=0.04; OR=1.37, 95%CI 1.01-1.85) genetic model. Same genetic variant was found to be associated with the clinical stage of localized PCa, as well as with the presence of distant metastases. Allele G of rs3746444 was also shown to be associated with the decreased risk of PCa progression. According to our data, rs3746444 qualifies for a genetic variant potentially associated with PCa aggressiveness in Serbian population. Furthermore, our study provided the first evidence of association between rs895819 and PCa risk, as well as for its genetic association with the presence of distant metastases among PCa patients.

Association between rs11614913 polymorphism in miR-196a2 and colorectal cancer risk: a meta-analysis

BACKGROUND

MicroRNAs (miRNAs) are small non-coding RNAs of 20-22 nucleotides in length, which regulate the translation or degradation of human messenger RNA (mRNA). MiRNAs involve in the regulation of most biological processes, as well as human diverse diseases including cancer. Recently, many studies investigated the association between miR-196a2 rs11614913 polymorphism and colorectal cancer (CRC), which showed inconclusive results.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a meta-analysis of 6 studies that included 1800 cases and 2329 controls. There was a statistically decreased risk of CRC in dominant model, recessive model and homozygous model. In the Asian group, significantly decreased susceptibility of CRC was found in allele model, dominant model, recessive model and homozygous model. As for the Caucasian group, none of genetic models demonstrates significant association between miR-196a2 rs11614913 polymorphism and susceptibility of CRC.

CONCLUSIONS

These findings supported that miR-196a2 rs11614913 polymorphism may contribute to the susceptibility of CRC.