The association of polymorphisms in miRNAs with nonsmall cell lung cancer in a Han Chinese population

The Insulin-like Growth Factor System and Colorectal Cancer

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

Association Between miR-143/145 rs4705343 Polymorphism and Risk of Congenital Heart Disease in a Chinese Tibetan Population

Objective: Congenital heart disease (CHD) is the most common birth defect worldwide and is caused by both genetic and environmental factors. The microRNA (miR)-143/145 cluster is involved in various biological processes related to cardiovascular development. The functional single nucleotide polymorphism (SNP) rs4705343 of miR-143/145 may influence the expression of these miRNAs. In this study, we aimed to estimate the association between miR-143/145 rs4705343 and the risk of CHD in a Chinese Tibetan population. Methods: Matrix-assisted laser desorption ionization time-of-flight mass spectrometry assays were performed to genotype the miRNA-143/145 rs4705343 SNP in 510 CHD Tibetan patients and 681 unrelated Tibetan healthy controls. The associations between the SNP frequencies and the CHD risk were analyzed by χ² test/Fisher's test and assessed by odds ratios (ORs) and 95% confidence intervals (95% CIs). Results: We successfully genotyped 1165 subjects with a SNP call rate of 97.8%. Under the allelic model we found that rs4705343 was not associated with the risk of CHD (p = 0.082), but under the recessive model the CC genotype at this locus was associated with a significantly increased risk of CHD compared with the other genotypes (CC vs TT+TC: OR = 1.60, 95% CI = 1.08-2.37, p = 0.017). Conclusion: The present study suggests that the rs4705343 CC genotype of miR-143/145 is associated with CHD risk in a Chinese Tibetan population.

Functional Variants of miR-143 Are Associated with Schizophrenia Susceptibility: A Preliminary Population-Based Study and Bioinformatics Analysis

Single nucleotide polymorphisms within genes encoding microRNAs may alter the expression of microRNAs and their target genes, contributing to the etiology of psychiatric disorders. We aimed to investigate the link between rs4705342T/C and rs4705343T/C polymorphisms in the promoter region of miR-143 and the risk of schizophrenia (SCZ) in a sample of an Iranian population. In this experimental study, a total of 398 subjects were recruited. Genotyping carried out using allele-specific PCR (AS-PCR) method. Different bioinformatics databases and Cytoscape V3.4.0 software were used for the analysis of the gene-miRNA interaction network. The genotypic analysis of rs4705342C/T showed that CC genotype in the co-dominant model significantly decreased the risk of SCZ (p < 0.001). Also, a significantly reduced risk of SCZ was observed under allelic (p < 0.001), dominant (p = 0.007), and recessive (p = 0.001) models of this variant. As regards rs4705343T/C, significantly enhanced risk of SCZ was found under the co-dominant CC (p = 0.01) and recessive (p = 0.007) contrasted genetic models. For this variant, the C allele conferred an increased risk of SCZ by 1.41 fold. Haplotype analysis showed that the C_rs4705342 T_rs4705343 haplotype significantly diminished SCZ susceptibility. The result of the bioinformatics analysis showed that miR-143, as a critical miRNA, targets ERK5, ERBB3, HK2, and PKCε, the four major genes involved in SCZ development. Our findings suggest that these two polymorphisms might affect SCZ susceptibility. Elucidating the precise regulatory mechanisms of gene expression in the development of SCZ will help researchers discover a novel target for therapeutic interventions.

Association between the rs3733846 in the flanking region of miR-143/145 and risk of cervical squamous cell carcinoma

Aim: To investigate the effect of rs3733846 in the flanking region of miR-143/145 on susceptibility to cervical squamous cell carcinoma (CSCC). Materials & methods: We collected venous blood samples from 242 CSCC patients and 250 healthy controls. The rs3733846 polymorphism was genotyped by SnaPshot and Sanger sequencing. The expression of miR-143/145 in CSCC tissues was detected by quantitative real-time PCR. Results: The rs3733846 AG genotype was associated with a decreased risk of CSCC in genetic model (AGvs.AA: adjusted odds ratio [OR]: 0.44; 95% CI: 0.30-0.66; p < 0.001). Patients with the rs3733846 AG/GG genotypes had a reduced risk of developing poorly differential status (OR: 0.57; 95% CI: 0.33-0.98; p < 0.04) and lymph node metastasis (OR: 0.49; 95% CI: 0.26-0.92; p < 0.03). Conclusion: The rs3733846 in the flanking region of miR-143/145 was related to the susceptibility of CSCC.

Association analysis of miRNA-related genetic polymorphisms in miR-143/145 and KRAS with colorectal cancer susceptibility and survival

Background: There is accumulating evidence of aberrant expression of miR-143 and miR-145 and their target gene KRAS in colorectal cancer (CRC). We hypothesize that single nucleotide polymorphisms (SNPs) within or near mRNA–microRNA (miRNA) binding sites may affect miRNA/target gene interaction, resulting in differential mRNA/protein expression and promoting the development and progression of CRC. Methods: We conducted a case–control study of 507 patients with CRC recruited from a tertiary hospital and 497 population-based controls to assess the association of genetic polymorphisms in miR-143/145 and the KRAS 3′ untranslated region (3′UTR) with susceptibility to CRC and patients’ survival. In addition, genetic variations of genomic regions located from 500 bp upstream to 500 bp downstream of the miR-143/miR-145 gene and the 3′UTR of KRAS were selected for analysis using the Haploview and HaploReg software. Results: Using publicly available expression profiling data, we found that miR-143/145 and KRAS expression were all reduced in rectal cancer tissue compared with adjacent non-neoplastic large intestinal mucosa. The rs74693964 C/T variant located 65 bp downstream of miR-145 genomic regions was observed to be associated with susceptibility to CRC (adjusted odds ratio (OR): 2.414, 95% CI: 1.385–4.206). Cumulative effects of miR-143 and miR-145 on CRC risk were observed (P_trend=0.03). Patients having CRC carrying variant genotype TT of KRAS rs712 had poorer survival (log-rank P=0.044, adjusted hazard ratio (HR): 4.328, 95% CI: 1.236–15.147). Conclusions: Our results indicate that miRNA-related polymorphisms in miR-143/145 and KRAS are likely to be deleterious and represent potential biomarkers for susceptibility to CRC and patients’ survival.

Association between microRNA-146a, -499a and -196a-2 SNPs and non-small cell lung cancer: a case-control study involving 2249 subjects

MicroRNA (miR) acts as a negative regulator of gene expression. Many literatures have suggested that miRs may be involved in the process of cell proliferation, inflammation, oxidative stress, energy metabolism and epithelial–mesenchymal transition. Thus, miRs may be implicated in the occurrence of non-small cell lung cancer (NSCLC). In the current investigation, we included 2249 subjects (1193 NSCLC patients and 1056 controls) and designed a study to identify the relationship of miR-146a rs2910164 C/G, -499a rs3746444 A/G and -196a-2 rs11614913 T/C with the risk of NSCLC. The risk factors (e.g., body mass index (BMI), sex, smoking, drinking and age) was used to adjust the odds ratios (ORs) and 95% confidence intervals (CIs). After conducting a power value assessment, we did not confirm that the miR-single nucleotide polymorphisms (SNPs) genotypic distributions were different in NSCLC cases and controls. However, the association of miR-196a-2 rs11614913 with a decreased risk of NSCLC was identified in the female subgroup (adjusted P=0.005, power = 0.809 for TC vs. TT, and adjusted P=0.004, power = 0.849 for CC/TC vs. TT). In addition, gene–gene interaction analysis showed that rs11614913 TC/3746444 AA and rs11614913 CC/rs3746444 AA could also reduce the susceptibility to NSCLC (rs11614913 TC/rs3746444 AA vs. rs11614913 TT/rs3746444 AA, P=0.001, power = 0.912 and rs11614913 CC/rs3746444 AA vs. rs11614913 TT/rs3746444 AA, P=0.003, power = 0.836). In conclusion, in overall comparisons, we did not confirm that the rs2910164, rs3746444, and rs11614913 SNPs genotypic distributions were different in NSCLC cases and controls. However, this case–control study demonstrates that miR-196a-2 rs11614913 may be a protective factor for the development of NSCLC among female patients.

Association of Hsa-miR-23a rs3745453 variation with prostate cancer risk among Chinese Han population: A case-control study

Prostate cancer (PCa) is a frequently diagnosed malignant solid tumor in men. The etiology of PCa has been attributed to both environmental and genetic factors. In recent years, many studies have reported that miRNA gene single-nucleotide polymorphisms (SNPs) influence the susceptibility to several diseases such as cancer. To date, the mechanisms of PCa have remained unknown. The main aim of this study was to evaluate the association between PCa susceptibility and miRNA gene SNPs. A total of 156 PCa cases and 188 control subjects were included in this case-control study. The data were collected from hospitalized cases. We collected the demographic characteristic information, which included age, body mass index, tobacco smoking, alcohol consumption, and family history of cancer. Polymorphisms were analyzed by the ligase detection reaction. Unconditional logistic and stratified analyses were used to analyze the association between these SNPs and PCa susceptibility and to calculate the adjusted odds ratios (ORs) and the 95% confidence intervals (CIs). Cox regression model and the log-rank test were used to test the association between genetic variants and the overall survival. We found that miR-23a gene polymorphism rs3745453 carrying CC homozygotes had a 4.16-fold increased risk (95% CI = 1.30-13.25) than those carrying the TT/CT genotypes (P = .02), and the C allele displayed a higher prevalence of PCa than the T allele (OR = 1.68, 95% CI = 1.16-2.45, P = .01). Moreover, miR-23a showed that the homozygous carriers of the C-variant significantly increased the risk of survival rate as compared to the carriers of the TT/CT genotype (OR = 9.67, 95% CI = 2.83-33.09, P = .001). The rs3745453 polymorphism was potentially associated with PCa in the Chinese Han population and had an interactive relationship with the environmental factors.

MiR-218 and miR-100 polymorphisms as markers of irinotecan-based chemotherapy response in metastatic colorectal cancer

PURPOSE

Colorectal cancer is the fourth cause of cancer-related death. Drug toxicity and resistance remain concerns of major importance. miR-100 and miR-218 are micro-RNAs that regulate cellular proliferation, differentiation and apoptosis acting as oncogenes and tumour suppressors; their functions and have been linked with toxicity development and drug resistance.

METHODS

We investigated the correlation between rs11134527 miR-218 and rs1834306 miR-100 polymorphisms and irinotecan-based regimens with regard to drug efficacy and toxicity. A total of 105 mCRC patients receiving irinotecan-based regimens were included in our study and assessed in terms of toxicity development and response to treatment. Rs11134527 miR-218 and rs1834306 miR-100 polymorphism genotyping in the peripheral blood was performed with PCR-RFLP.

RESULTS

Neither rs11134527 miR-218 nor rs1834306 miR-100 are associated with toxicity risk to treatment regimens. GA/AA genotypes of rs11134527 and CT/TT genotypes of rs1834306 were associated with a significantly reduced time-to-progression (TTP) and overall survival (OS).

CONCLUSIONS

GA/AA genotypes of rs11134527 miR-218 and CT/TT genotypes of rs1834306 miR-100 polymorphisms could serve as prognostic biomarkers of TTP and OS. Carriers of the A allele of the miR-218 rs11134527 and T allele of the miR-100 rs1834306 polymorphisms are more likely not to respond to irinotecan-based therapies. However, further studies in larger patient populations are required.

Polymorphisms in miRNA genes play roles in the initiation and development of cervical cancer

MicroRNA deregulation is crucial for cancer development. Studies showed that polymorphisms in miRNA genes could affect miRNA expression, which might be associated with cancer development. In the current study, we investigated the association of seven single nucleotide polymorphisms (SNPs) in seven miRNA genes with the initiation and development of cervical cancer in a Chinese Han population. The SNPs of 358 cervical intraepithelial neoplasia (CIN) patients, 547 cervical cancer patients and 567 healthy individuals were genotyped using TaqMan assays. Moreover, we evaluated the association of the seven SNPs with the different stages of cervical cancer. Our results showed that rs4636297 in miR-126 was associated with susceptibility to CIN and cervical cancer (P=0.019 and 0.019, respectively) and that the T allele was associated with a higher risk of CIN (OR=1.334, 95% CI: 1.049-1.698) and cervical cancer (OR=1.296, 95% CI: 1.044-1.609). Similarly, rs11614913 in miR-125a was associated with CIN and cervical cancer (P=0.025 and 0.015, respectively), and the T allele might be the protective factor for CIN (OR=0.807, 95% CI: 0.669-0.974) and cervical cancer (OR=0.814, 95% CI: 0.689-0.961). Our results indicated that rs4636297 in miR-126 and rs11614913 in miR-196a2 play an important role only in the initiation of cervical cancer not in the development of CIN to cervical cancer.

Association between miR-218 rs11134527 polymorphism and risk of selected types of cancer in Asian population: An updated meta-analysis of case-control studies

Several studies inspected the relationship between miR-218 rs11134527 polymorphism and the risk of some human cancers, but the findings remains controversial. We designed an update meta-analysis aiming to validate the association between rs11134527 polymorphism of miR-218 and cancer risk. Eligible studies including 7989 cancer cases and 8761 controls were recognized by searching Web of Science, PubMed, Scopus, and Google scholar databases. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to quantitatively evaluate the association between rs11134527 variant and cancer risk. The overall results indicated no significant relationship between miR-218 rs11134527 polymorphism and cancer risk in codominant, dominant, recessive, overdominant, and allele inheritance model tested. Stratified analysis showed that rs11134527 variant significantly increased the risk of developing esophageal squamous cell carcinoma (ESCC) in heterozygous codominant (OR = 1.32, 95%CI = 1.03-1.69, p = 0.03, AG vs GG) inheritance model. In summary, the findings of this meta-analysis did not support an association between miR-218 rs11134527 polymorphism and cancer risk. Stratified analysis showed that rs11134527 variant significantly increased the risk of developing ESCC. Larger and well-designed researches are needed to estimate this association in detail.

Involvement of microRNA-423 Gene Variability in Breast Cancer Progression in Saudi Arabia

Aim:

microRNA-423 is an oncogenic factor which is frequently upregulated in cancer. However, associations with breast cancer risk remain inconsistent. Therefore, we investigated the prevalence of microRNA-423 rs6505162C>T gene variation with breast cancer susceptibility in Saudi women.

Methodology:

This study was conducted on 100 breast cancer patients and 124 matched healthy individuals. Genotyping of the microRNA-423 rs6505162C/T gene variation was performed by using the amplification refractory mutation system PCR method (ARMS-PCR).

Results:

A significant difference was observed in the genotype distribution between the breast cancer cases and controls (p=0.0001), the frequencies of the genotypes CC,CT and TT being 25%, 52% and 23% in patients and 65%,20% and 15% respectively, in controls. The microRNA-423 C>T variant was associated with an increased risk of breast cancer in codominant models for (OR = 6.73, 95 % CI, 3.50-12.97; RR 2.35(1.67-3.30, p=0.0001) the microRNA-423TT genotype and (OR = 4.14, 95 % CI, 1.93-8.87; p=0.0003) microRNA-423CT (OR= 6.73, 95% CI, 3.50-12.97; p=0.0001) and also with the dominant model (OR 5.6(3.14-1.01), p=0.0001) CT+TT vs CC) with a non-significant association for the recessive model (OR=1.75, 95%CI=0.08-3.44, P=0.139, TT vs CC+CT). The T allele significantly increased the risk of breast cancer (OR =2.63, 95 % CI, 1.77-3.91; p=0.001) compared to the C allele. Some 6.73 ,4.14 and 2.63 fold increased risk of developing breast cancer was associated with TT and CT genotypes and the T allele of microRNA-423 in the northwestern region of Saudi Arabia.

Conclusion:

Our findings indicate that the microRNA-423 TT genotype and the T allele are associated with an increased susceptibility, metastasis and advanced stage of breast cancer in Saudi Arabian patients. Further studies with larger sample sizes are necessary to confirm our findings.

Upregulated expression of miR-421 is associated with poor prognosis in non-small-cell lung cancer

Background

Non-small-cell lung cancer (NSCLC) represents the most frequent subtype of lung cancer. MicroRNAs (miRNAs) have attracted a lot of attention with regard to their clinical significance and crucial biological functions in various human cancers. This study aimed to investigate the prognostic significance of microRNA-421 (miR-421) and its correlation with tumor progression in NSCLC.

Materials and methods

Expression levels of miR-421 in both serum and tissue samples were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The prognostic value of miR-421 was evaluated using Kaplan–Meier survival analysis and Cox regression assay. To explore the functional role of miR-421 during NSCLC progression, cell experiments were carried out.

Results

Expression of serum and tissue miR-421 was upregulated in the NSCLC patients compared with the normal controls (all P<0.001), and the expression showed a significant correlation between the serum samples and tissues (R=0.475, P<0.001). The increased miR-421 expression was associated with positive lymph-node metastasis and advanced TNM stage (all P<0.05). Moreover, patients with high miR-421 expression had poor overall survival compared with those with low expression (log-rank P=0.007). The overexpression of miR-421 proved to be an independent prognostic factor for NSCLC (HR=1.991, 95% CI=1.046–3.791, P=0.036). According to the cell experiments, the proliferation, migration and invasion of NSCLC cells were suppressed by knockdown of miR-421.

Conclusion

Overexpression of miR-421 serves as a prognostic biomarker and may be involved in the promotion of tumor progression in NSCLC.