Analysis of association of potentially functional genetic variants within genes encoding miR-34b/c, miR-378 and miR-143/145 with prostate cancer in Serbian population

Deletion in a regulatory region is associated with underexpression of miR-148b‑3p in patients with prostate cancer

Prostate cancer (PCa) is the leading cause of cancer-related death in men. This pathology is complex and heterogeneous; therefore, elucidating the molecular mechanisms that lead to its origin and progression is imperative. MicroRNAs (miRNAs or miRs) are part of the epigenetic machinery that regulates the expression of human genes, therefore, mutations in the genes that encode them can lead to a dysregulation in their expression, which directly impacts their target genes, which could be oncogenes or tumor suppressor genes. In PCa several dysregulated expression levels of miRNAs are associated with perturbed cellular processes. A differential expression of miRNAs such as miR-145-5p and miR-148-3p has been observed in PCa, possibly due to mutations in regions near the miRNAs. However, the molecular mechanisms that lead to the dysregulation of these miRNAs still need to be clarified. Therefore, the present study aimed to analyze the expression of miRNAs and their relationship with mutations in patients with and without PCa. In total, 71 patients were analyzed: 41 of whom had PCa (CAP group) and 30 with benign pathology (BPD group). Underexpression was observed in miR-145-5p and miR-148b-3p in PCa patients (P=0.03 and P=0.001, respectively). In miR-145-5p, no mutations related to its expression were identified. For miR-148b-3p, a set of mutations were identified in the chr12:54337042/54337043 region, which were grouped into the mutation named DelsAAG. Although this mutation's abnormal allele is related to PCa (P=0.017), a statistically significant difference was observed in the expression of miR-148b-3p between carriers and non-carriers of the mutated allele, identifying a mechanism likely to be involved in the miR-148b-3p dysregulation.

The polymorphism rs4705342 in the promoter of miR-143/145 is related to the risk of epithelial ovarian cancer and patient prognosis

Objective

To evaluate the effects of two genetic variants in the promoter of the miR-143/145 cluster on the risk of epithelial ovarian cancer (EOC) and the prognosis of EOC patients.

Study design

Genotypes were determined by the polymerase chain reaction and ligase detection reaction method in 563 EOC patients and 576 healthy women. The expression of miR-143 and miR-145 were detected by quantitative real-time polymerase chain reaction (qRT-PCR) in fifty-two EOC tissues.

Results

The rs4705342 CC genotype frequencies in EOC patients were higher than those in the controls (P = 0.014). Furthermore, the CC genotype of rs4705342 was associated with an advanced FIGO stage of EOC patients (P = 0.046). Patients with the rs4705342 CC genotype had shorter progression-free survival (PFS) and overall survival (OS) times than those carrying the TT genotype in multivariable analysis adjusting for clinical variables (HR = 1.30, 95% CI = 1.04-1.62, P = 0.020; HR = 1.33, 95% CI = 1.05-1.70, P = 0.020). In addition, the miR-145 levels were lower in EOC tissues with the rs4705342 CC genotype than in those with the TT genotype (P = 0.005).

Conclusion

The CC genotype of rs4705342 was related to an increased risk of EOC and poor prognosis of EOC patients, and rs4705342 may serve as a molecular marker for predicting the development of EOC and the clinical outcome of EOC patients.

Genetic variants in miR-145 gene are associated with the risk of asthma in Taiwan

Asthma is a chronic airway inflammation disease and the diagnosis and treatment strategies remain difficult. MicroRNAs play important roles in many biological and pathological processes including asthma development. There is no study confirming the contribution of genetic variants in miR-145 to asthma etiology. We hypothesize that single nucleotide polymorphisms (SNPs) in the promoter region of miR-145 may be associated with the risk of asthma in Taiwanese. We used a case–control study to test this hypothesis. In 198 asthma patients and 453 healthy controls, the genotypes of miR-145 rs4705342 and rs4705343 were determined, and the associations of miR-145 genotypes with asthma risk and severity were evaluated. The distribution of miR-145 rs4705342 genotypes between asthma patients and non-asthmatic control groups were significantly different (p = 0.0187). In multivariable logistic regression analysis, compared with the wild-type TT genotype, individuals carrying the variant genotypes had progressively decreased risks of asthma: the odds ratio (OR) for the heterogeneous variant genotype (CT) and homozygous variant genotype (CC) was 0.77 (95% CI 0.55–1.10, p = 0.1788) and 0.41 (95% CI 0.21–0.79, p = 0.0102), respectively (p for trend = 0.0187). In allelic test, the C allele was associated with a 31% reduced risk of asthma (OR = 0.69, 95% CI 0.53–0.90, p = 0.0070). In addition, the rs4705342 variant genotypes were correlated with the symptom severity (p = 3 × 10^–5). Furthermore, the variant genotypes correlated with lower miR-145-5p expression level in serum (p = 0.0001). As for rs4705343, there was no differential distribution of genotypes between cases and controls. Our data provide evidence for miR-145 rs4705342 to serve as a novel biomarker for asthma risk prediction.

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.

A functional polymorphism of microRNA-143 is associated with the risk of type 2 diabetes mellitus in the northern Chinese Han population

OBJECTIVE

To explore the association between two polymorphisms of microRNA-143 (miR-143) and the risk of type 2 diabetes mellitus (T2DM) in the northern Chinese Han population.

STUDY DESIGN

This case-control study involved 326 patients with T2DM and 342 healthy controls. Two genetic variants (rs4705342 and rs353292) of miR-143 were genotyped by the polymerase chain reaction/ligase detection reaction (PCR-LDR) method. The levels of miR-143 in the serum from 52 T2DM patients and 55 healthy subjects were investigated by quantitative real-time PCR (qRT-PCR).

RESULTS

The CC genotype frequency of rs4705342 was significantly higher in the T2DM patients than in the healthy controls (P = 0.012). After adjusting for sex, age, and body mass index, the rs4705342 CC genotype was also related to a significantly increased risk of T2DM compared with the TT genotype (adjusted OR: 1.87; 95% CI = 1.09-3.19; P = 0.022). Stratified analyses demonstrated that T2DM patients with the rs4705342 CC genotype had significantly higher levels of low-density lipoprotein cholesterol (LDL-C), fasting blood glucose (FBG), and glycated haemoglobin (HbA1C) than those carrying the rs4705342 TT genotype. The qRT-PCR results showed that the expression levels of miR-143 were significantly higher in the serum of cases than in the serum of controls (P < 0.001). Furthermore, the levels of miR-143 were significantly higher in the serum of T2DM patients carrying the rs4705342 CC genotype than in those carrying the TC and TT genotypes of rs4705342 (P = 0.005 and 0.003, respectively).

CONCLUSION

The CC genotype of rs4705342 might be a risk factor for developing T2DM by increasing the expression of miRNA-143 in the northern Chinese Han population.

Deciphering the role of microRNAs in mustard gas-induced toxicity

Mustard gas (sulfur mustard, SM), a highly vesicating chemical warfare agent, was first deployed in warfare in 1917 and recently during the Iraq-Iran war (1980s) and Syrian conflicts (2000s); however, the threat of exposure from stockpiles and old artillery shells still looms large. Whereas research has been long ongoing on SM-induced toxicity, delineating the precise molecular pathways is still an ongoing area of investigation; thus, it is important to attempt novel approaches to decipher these mechanisms and develop a detailed network of pathways associated with SM-induced toxicity. One such avenue is exploring the role of microRNAs (miRNAs) in SM-induced toxicity. Recent research on the regulatory role of miRNAs provides important results to fill in the gaps in SM toxicity-associated mechanisms. In addition, differentially expressed miRNAs can also be used as diagnostic markers to determine the extent of toxicity in exposed individuals. Thus, in our review, we have summarized the studies conducted so far in cellular and animal models, including human subjects, on the expression profiles and roles of miRNAs in SM- and/or SM analog-induced toxicity. Further detailed research in this area will guide us in devising preventive strategies, diagnostic tools, and therapeutic interventions against SM-induced toxicity.

Association of KLK3, VAMP8 and MDM4 Genetic Variants within microRNA Binding Sites with Prostate Cancer: Evidence from Serbian Population

A growing number of studies have suggested that genetic variants affecting the micro-RNA- binding mechanisms (miRSNPs) constitute a promising novel class of biomarkers for prostate cancer (PCa) biology. Among the most extensively studied miRSNPs in the context of cancer is the variation rs4245739 in the MDM4 gene, while a recent large-scale analysis revealed significant differences in genotype distributions between aggressive and non-aggressive disease for rs1058205 in KLK3 and rs1010 in VAMP8. In this study, we examined a total of 1083 subjects for these three variants using Taqman® SNP Genotyping Assays. Three hundred and fifty-five samples of peripheral blood were obtained from patients with PCa and 358 samples from patients with benign prostatic hyperplasia (BPH). The control group consisted of 370 healthy volunteers. Comparisons of genotype distributions among PCa and BPH patients, as well as between PCa patients and healthy controls, yielded no evidence of association between the analyzed genetic variants and the risk of developing PCa. However, all three tested genetic variants have shown the association with the parameters of PCa progression. For KLK3 variant rs1058205, minor allele C was found to associate with the lower serum PSA score in PCa patients (PSA > 20 ng/ml vs. PSA < 10 ng/ml comparison, Prec = 0.038; ORrec = 0.20, 95%CI 0.04-1.05). The obtained results point out the potential relevance of the tested genetic variants for the disease aggressiveness assessment.