Pri-miR-34b/c rs4938723 polymorphism increased the risk of prostate cancer

Functional pri-miR-34b/c rs4938723 and KRAS 3'UTR rs61764370 SNPs: Novel phenotype modifiers in Li-Fraumeni Syndrome?

PURPOSE

Li-Fraumeni Syndrome (LFS) is a rare cancer predisposing condition caused by germline pathogenic TP53 variants, in which core tumors comprise sarcomas, breast, brain and adrenocortical neoplasms. Clinical manifestations are highly variable in carriers of the Brazilian germline founder variant TP53 p.R337H, possibly due to the influence of modifier genes such as miRNA genes involved in the regulation of the p53 pathway. Herein, we investigated the potential phenotypic effects of two miRNA-related functional SNPs, pri-miR-34b/c rs4938723 and 3'UTR KRAS rs61764370, in a cohort of 273 LFS patients from Southern and Southeastern Brazil.

METHODS

The genotyping of selected SNPs was performed by TaqMan® allelic discrimination and subsequently custom TaqMan® genotyping results were confirmed by Sanger sequencing in all SNP-positive LFS patients.

RESULTS

Although the KRAS SNP showed no effect as a phenotype modulator, the rs4938723 CC genotype was significantly associated with development of LFS non-core tumors (first tumor diagnosis) in p.R337H carriers (p = 0.039). Non-core tumors were also more frequently diagnosed in carriers of germline TP53 DNA binding domain variants harboring the rs4938723 C variant allele. Previous studies described pri-miR-34b/c rs4938723 C as a risk allele for sporadic occurrence of thyroid and prostate cancers (non-core tumors of the LFS spectrum).

CONCLUSION

With this study, we presented additional evidence about the importance of analyzing miRNA genes that could indirectly regulate p53 expression, and, therefore, may modulate the LFS phenotype, such as those of the miR-34 family.

MicroRNA-34 Family in Cancers: Role, Mechanism, and Therapeutic Potential

MicroRNA (miRNA) are small noncoding RNAs that play vital roles in post-transcriptional gene regulation by inhibiting mRNA translation or promoting mRNA degradation. The dysregulation of miRNA has been implicated in numerous human diseases, including cancers. miR-34 family members (miR-34s), including miR-34a, miR-34b, and miR-34c, have emerged as the most extensively studied tumor-suppressive miRNAs. In this comprehensive review, we aim to provide an overview of the major signaling pathways and gene networks regulated by miR-34s in various cancers and highlight the critical tumor suppressor role of miR-34s. Furthermore, we will discuss the potential of using miR-34 mimics as a novel therapeutic approach against cancer, while also addressing the challenges associated with their development and delivery. It is anticipated that gaining a deeper understanding of the functions and mechanisms of miR-34s in cancer will greatly contribute to the development of effective miR-34-based cancer therapeutics.

Analysis of Rare Alleles of miRNA-146a (rs2910164) and miRNA-34b/c (rs4938723) as a Prognostic Marker in Thyroid Cancer in Pakistani Population

Background: Rationale: The miRNAs are short non-coding functional RNAs that are involved in the regulation of transcriptomes. It was found that human miRNA-146a and miRNA34b/c are important microRNAs and are functioning either as onco-miRNAs, or acting as tumor suppressors, in different conditions. To date, no study has been performed to evaluate the alterations of miRNA-146ars2910164 and miRNA34b/crs4938723 polymorphism as a risk factor in the development of thyroid cancer in the Pakistani population. Mutational analysis of rs2910164 and rs4938723 of miRNA-146a and miRNA-34b/c was carried out to check their association with the development of thyroid carcinogenesis. Material and Methods: Papillary thyroid cancer (PTC) patients with age and gender-matched controls were recruited for the present study. DNA extraction, genotyping of rs2910164 and rs4938723 was carried out by ARMS-PCR. Statistical analyses were carried out using SPSS software (version 20). Results: The odds ratio for risk allele C of rs2910164 for patients and controls was 23.0168 (3.0321−174.7208) with a p-value of <0.0001, showing that the frequency of the major allele G was lower in patients while the frequency of minor allele C was higher in patients. Similarly, the odds ratio for risk allele C of rs4938723 was 1.8621 (1.0321−3.3596) with a p-value of <0.03788 showing significant association with the development of thyroid cancer. Conclusions: The study highlights the significant association of miRNAs SNPs as one of the genetic risk factor for PTC. It was concluded that miRNA-146a (rs2910164) showed higher frequency of minor allele C in patients. Similarly in miRNA-34b/c gene SNP rs4938723 was observed to have a strong association with the development of thyroid cancer as the frequency of rare allele C was higher in patients.

Association between microRNA 671 polymorphisms and the susceptibility to soft tissue sarcomas in a Chinese population

This study evaluated the association between the microRNA (miRNA) gene polymorphisms and the susceptibility to soft tissue sarcomas (STSs). In this case–control study, DNA was extracted from leukocytes in peripheral blood, which was collected from 169 STSs patients and 170 healthy controls. Three SNPs for miR-210, five SNPs for miR-206, two SNPs for miR-485, two SNPs for miR-34b, two SNPs for miR-671, and three SNPs for miR-381 were investigated and genotyped using a Sequenom Mass ARRAY matrix-assisted laser desorption/ionization-time of flight mass spectrometry platform. Unconditional logistic regression analysis was used to analyze the association between miRNA gene polymorphisms and the susceptibility to STSs. The results showed that miR-671 rs1870238 GC + CC (OR = 1.963, 95% CI = 1.258–3.064, P = 0.003) and miR-671 rs2446065 CG + GG (OR =1.838, 95% CI = 1.178–2.868, P = 0.007) may be genetic risk factors for STSs after adjustment for age and smoking. Therefore, this study suggests that individuals carrying the GC + CC genotype for miR-671 rs1870238 or the CG + GG genotype for miR-671 rs2446065 are susceptible to STSs.

Relevance of Interleukins 6 and 8 Single Nucleotide Polymorphisms in Prostate Cancer: A Multicenter Study

The diverse roles of cytokines as IL-6 and IL-8 have been studied in terms of their SNPs in many diseases but their role in prostate cancer (PCa) is still uncertain. Aim. To determine the relevance of IL-6 rs1800795 SNP and/or IL-8 rs2227306 SNP with prostate cancer's risk. Subjects and Methods. 40 PCa patients, 40 benign prostate hyperplasia (BPH) patients, and 40-age-matched-control group were enrolled in the study. Genotyping of IL-6 rs1800795 (G/C) SNP and IL-8 rs2227306 (C/T) SNP was determined using real-time PCR. Results. High frequency of IL-6 rs1800795GG and IL-8 rs2227306CC genotypes was noticed among PCa patients with associated OR 10.091 and 8.143, respectively. Comparisons based on allele frequencies revealed that IL-6G and IL-8C alleles are more frequent among PCa patients than other groups. Presence of IL-6 rs1800795G and IL-8 rs2227306C alleles in the same patient increase PCa risk by 16.7 times. Statistical correlations between PSA ratio and both of IL-6 and IL-8 SNP did not show any significant relation among PCa patients. Conclusion. IL-6 rs1800795G and IL-8 rs2227306C alleles could be considered risk factors for PCa development, particularly if presented together. However, no relation was found between both cytokines SNP and severity of prostate cancer.

Evaluation of miR-34b/c polymorphisms to the risk of ischemic stroke

OBJECTIVES

Polymorphisms in microRNA genes are related to the risk of ischemic stroke, but the association between miR-34b/c polymorphisms and the risk of ischemic stroke has not been reported.

METHODS

MiR-34b/c rs2187473 and rs4938723 polymorphisms were genotyped by Snapshot assay among 495 controls and 492 ischemic stroke patients. Expression levels of miR-34b and miR-34c were quantified by real-time PCR. Transcriptional activity of miR-34b/c promoter was measured by luciferase reporter assay.

RESULTS

Rs4938723 was associated with an increased risk of ischemic stroke in our study (CC versus TT: OR = 2.34, 95% CI = 1.47-3.72, P = 0.001; C versus T: OR = 1.37, 95% CI = 1.12-1.68, P = 0.002; CC versus TT + TC: OR = 2.12, 95% CI = 1.37-3.29, P = 0.001). The expression levels of miR-34b and miR-34c were significantly downregulated in cases by contrast with controls (P < 0.05). Further analysis demonstrated that the expression levels of miR-34b and miR-34c were also downregulated in the individuals carrying rs4938723 CC genotype by contrast with that carrying TT + TC genotypes (P < 0.05). The result of luciferase reporter assay showed that rs4938723C allele decreased the transcriptional activity of miR-34b/c promoter compared with rs4938723 T allele.

CONCLUSION

Our study showed a positive relation between the miR-34b/c rs4938723 polymorphism and the risk of ischemic stroke, which indicated that rs4938723 may be used for ischemic stroke prediction or therapy in the future.

Association of miR-34b/c rs4938723 and TP53 Arg72Pro Polymorphisms with Neuroblastoma Susceptibility: Evidence from Seven Centers

Neuroblastoma is a pediatric malignancy arising from the developing peripheral nervous system. p53 and downstream effector miR-34b/c have critical tumor suppressing functions. TP53 Arg72Pro (rs1042522 C > G) and miR-34b/c rs4938723 (T > C) polymorphisms have been known to modify cancer susceptibility. This study was performed to validate the association of these two polymorphisms and neuroblastoma risk with 819 cases and 1780 controls. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were used to assess the strength of the associations. False positive report possibility analysis was adopted to dissect out real significant associations from chance findings. We found that both TP53 Arg72Pro (CG/GG vs. CC: adjusted OR = 0.82, 95% CI = 0.69-0.98) and miR-34b/c rs4938723 (TC/CC vs. TT: adjusted OR = 0.64, 95% CI = 0.54-0.75) were associated with decreased neuroblastoma susceptibility. Stratify analyses further confirmed the protective effect among some subgroups. Moreover, subjects with variant alleles of both polymorphisms were associated with more significantly decreased neuroblastoma risk (CG/TC vs. CC/TT: adjusted OR = 0.38, 95% CI = 0.28-0.50; GG/TC vs. CC/TT: adjusted OR = 0.43, 95% CI = 0.30-0.63) than those carrying variant allele of either one polymorphism (CC/TC vs. CC/TT: adjusted OR = 0.51, 95% CI = 0.37-0.69; CG/TT vs. CC/TT: adjusted OR = 0.71, 95% CI = 0.55-0.92), suggesting cumulative effects of the polymorphisms. False positive report possibility analysis further verified that our findings are noteworthy. Overall, we confirmed that miR-34b/c rs4938723 and TP53 Arg72Pro conferred decreased neuroblastoma risk and two polymorphisms exerted stronger protective effects against neuroblastoma than either one alone.

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

MiRNA-associated genetic variants occurring in regulatory regions can affect the efficiency of transcription and potentially modify pri-miRNA or pre-miRNA processing. Since miRNA-based mechanisms are shown to be involved in the pathogenesis of prostate cancer (PCa), the aim of the present study was to evaluate the effect of rs4938723, rs1076064 and rs4705343 occurring in regulatory regions of miR-34b/c, miR-143/145 and miR-378, respectively, on PCa risk and progression in Serbian population. We examined a total of 1060 subjects, of which 350 were patients with PCa, 354 were patients with benign prostatic hyperplasia (BPH), while 356 healthy volunteers were included in the control group. Genotyping of rs4938723, rs1076064 and rs4705343 was performed by using Taqman^® SNP Genotyping Assays. Allele C of rs4705342 was found to increase the risk of PCa (P=0.031 for codominant model, P=0.0088 for recessive model). Rs1076064 minor allele G was found to associate with serum PSA score, as well as with PCa T category and disease aggressiveness. For rs4938723 minor allele C was shown to be associated with the lower PCa T category (P_dom=0.0046; OR=0.36, 95 % CI 0.17-0.76) in T2 vs. T1 comparison. Rs4705342 was identified as PCa susceptibility variant in Serbian population, while for rs1076064 and rs4938723 association with PCa progression parameters was found.

Correlative analysis of miR-34b and p53 with pathological characteristics of NSCLC

The expression of miR-34b and p53 in non-small cell lung cancer (NSCLC) was investigated to explore its relationship with clinical pathology of NSCLC. Reverse transcription-quantitative PCR (RT-qPCR) method was used to quantitatively analyze miR-34b and p53 in cancer tissue and adjacent paraneoplastic (PTLC) tissue in 54 cases of NSCLC. The relationship between gene expression and clinical pathological data was analyzed. The expression of miR-34b in tumor tissues of NSCLC patients was significantly downregulated in comparison with PTLC. The expression level of miR-34b was negatively correlated with lymph node metastasis. It was positively correlated with the degree of differentiation and negatively correlated with the pathological stage (P<0.05). There was no significant association in the expression of miR-34b with age, sex, histological type, and gross classification (all P>0.05). The expression of p53 in the tumor tissue of NSCLC patients was significantly reduced in comparison with PTLC, and its expression was negatively correlated with the pathological stage, lymph node metastasis, and was positively correlated with the degree of differentiation. The expression of p53 in adenocarcinoma was generally higher than that of squamous cell carcinoma and large cell carcinoma. The expression of p53 in central type cancer was significantly higher than that in peripheral type (P<0.05). The expression of miR-34b and p53 was positively correlated in NSCLC tissues (r=0.797, P<0.001). The high expression of miR-34b and p53 is closely related to the clinical stage and pathological grade of NSCLC. miR-34b and p53 may serve as important tumor markers for NSCLC.

Prognostic significance of miR-34 rs4938723 T > C polymorphism in triple negative breast cancer patients

OBJECTIVES

The aim of this was the assessment of the prognostic role of the rs4938723 C > T polymorphism of the miR-34 in triple negative breast cancer patients.

METHODS

Therefore formalin fixed paraffin embedded tissue samples from 114 triple negative breast cancer patients and blood samples from 124 healthy donors were genotyped and subsequently extensive statistical analysis was performed in order to investigate the clinical value of this polymorphism in triple negative breast cancer.

RESULTS

Our statistical analysis disclosed that the majority of patients harboring ductal breast carcinoma (69.4%) have the TC or CC genotypes (P = .020). Moreover the survival of the patients was significantly correlated with the occurrence of the TC or CC alleles (P < .001). Regarding the correlation of miR-34 polymorphisms with patients' survival we found that women with TC or CC single nucleotide polymorphisms were characterized by shorter disease free survival intervals (P = .05). Furthermore triple negative breast cancer patients with TC/CC genotype exhibited shorter overall survival intervals as disclosed by Kaplan Meier analysis (P < .001) and Cox regression analysis (HR = 3.2, %95 CI = 2.0-5.5, P = .008). Stratified Kaplan-Meier analysis showed that the women harboring the TC or CC genotype along with the ductal histology had significantly shorter survival (P < .001). This result was also confirmed by Univariate Cox regression analysis, which showed that women ductal breast cancer and TC or CC genotype are of worse prognosis (HR = 2.35, %95 CI = 2.1-4.65, P = .003).

CONCLUSIONS

In conclusion, we found that the TC and CC alleles are associated with unfavorable prognosis in triple negative breast cancer patients.

Long non-coding RNA POLR2E gene polymorphisms increased the risk of prostate cancer in a sample of the Iranian population

The current study aimed to examine the impact of POLR2E rs1046040 and rs3787016 polymorphisms on prostate cancer (PCa) risk in a sample of southeast Iranian population. The present case-control study was performed on 178 patients with PCa and 180 benign prostatic hyperplasia (BPH). Genotyping of the variants was done by mismatch PCR-RFLP. The findings showed that the rs3787016 C > T variant significantly increased the risk of PCa in codominant (OR = 1.84, 95% CI = 1.12-3.03, P = 0.018, CT vs CC), dominant (OR = 1.88, 95% CI = 1.63-3.05, P = 0.011, CT + TT vas CC) and allele (OR = 1.77, 95% CI = 1.52-2.72, P = 0.010, T vs C) inheritance model. Regarding rs1046040 C > T polymorphism, the findings revealed that the CT genotype significantly increased the risk of PCa compared to the CC genotype (OR = 1.60, 95% CI = 1.03-2.49, P = 0.043). Furthermore, rs3787016 CT/rs1046040 CC as well as rs3787016 CT/rs1046040 CT increased the risk of PCa compared to the CC/CC genotype (p = 0.029 and p = 0.014, respectively). Haplotype analysis proposed that rs3787016 T/rs1046040 C significantly increased the risk of PCa compared to C/C (p = 0.037). No significant association was observed between POLR2E variants and clinicopathological characteristics of PCa patients. In conclusion, the findings propose that POLR2E variants may be a risk factor for susceptibility to PCa in a sample of Iranian population.

MicroRNA and Human Bone Health

The small non‐coding microRNAs (miRNAs) are post‐transcription regulators that modulate diverse cellular process in bone cells. Because optimal miRNA targeting is essential for their function, single‐nucleotide polymorphisms (SNPs) within or proximal to the loci of miRNA (miR‐SNPs) or mRNA (PolymiRTS) could potentially disrupt the miRNA‐mRNA interaction, leading to changes in bone metabolism and osteoporosis. Recent human studies of skeletal traits using miRNA profiling, genomewide association studies, and functional studies started to decipher the complex miRNA regulatory network. These studies have indicated that miRNAs may be a promising bone marker. This review focuses on human miRNA studies on bone traits and discusses how genetic variants affect bone metabolic pathways. Major ex vivo investigations using human samples supported with animal and in vitro models have shed light on the mechanistic role of miRNAs. Furthermore, studying the miRNAs’ signatures in secondary osteoporosis and osteoporotic medications such as teriparatide (TPTD) and denosumab (DMab) have provided valuable insight into clinical management of the disease. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research

Rs4938723 Polymorphism Is Associated with Susceptibility to Hepatocellular Carcinoma Risk and Is a Protective Factor in Leukemia, Colorectal, and Esophageal Cancer

BACKGROUND Growing evidence indicates that a non-coding RNA named miR-34b/c plays crucial roles in carcinogenesis, and its common polymorphism, pri-miR-34b/c rs4938723, also participates in this process and is associated with cancer susceptibility. However, this association was previously undefined and ambiguous. Therefore, we carried out an updated analysis to evaluate this relationship between rs4938723 polymorphism and cancer susceptibility. MATERIAL AND METHODS PubMed, EMbase, Web of Science and Chinese language (WanFang, CNKI and VIP) databases were searched for relevant studies until Sep 10, 2018. Odds ratios and 95% confidence interval were applied to assess this relationship. RESULTS Thirty case-control studies were retrieved. No positive association was found in either the overall study population or in the subgroups, based on ethnicity, source of group, sex, smoking, and drinking status. The main results were observed in the stratified analysis subgroups in cancer type subgroup: rs4938723 polymorphism may be a protective factor in leukemia, colorectal cancer, and esophageal cancer; however, C-allele was a risk factor in carriers for hepatocellular carcinoma. Last but not the least, poor positive results were discovered in the age subgroup. CONCLUSIONS Current meta-analysis suggested that rs4938723 polymorphism was potentially associated with hepatocellular carcinoma risk, but this polymorphism had a decreased association for susceptibility to esophageal cancer, leukemia, and colorectal cancer. Furthermore, studies with larger sample sizes and including gene-gene or gene-environment interactions should be carried out to elucidate the role of rs4938723 polymorphism in cancer risk.

Association Between Genetic Variant in the Promoter of Pri-miR-34b/c and Risk of Glioma

Growing evidence indicates that p53 can regulate the expression of miRNAs, particularly the miR-34 family members, which are described as potential tumor suppressors. Loss of miR-34 suppresses TP53-mediated cell death, whereas over expression of miR-34 induced apoptosis. The study designed to investigate the association between the pir-miR-34b/c rs4938723, TP53 Arg72Pro and the risk of glioma. We genotyped the two polymorphisms in175 glioma patients and 235 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing assay. Association analysis showed that the CC genotype of the pir-miR-34b/c rs4938723 was associated with a significantly decreased risk of glioma compared to the TT genotype (CC vs. TT: adjusted OR = 0.43;95% CI, 0.21–0.87,P = 0.02). Moreover, a significant association between the patients with glioma and controls was also observed in a recessive model (OR = 0.41; 95% CI, 0.21–0.81, P = 0.007). In contrast, the CC genotype of the TP53 Arg72Pro was associated with a significantly increased risk of glioma compared to the GG genotype (CC vs. GG: adjusted OR = 1.73;95% CI, 1.04–2.89,P = 0.04), and a significant association between the patients with glioma and controls was also observed in a recessive model (OR = 2.00; 95% CI, 1.26–3.18, P = 0.003). These findings suggest that the pri-miR-34b/c rs4938723CC and TP53 Arg72-Pro polymorphisms may be associated with the risk of glioma.

Association between miR-34b/c rs4938723 polymorphism and risk of cancer: An updated meta-analysis of 27 case-control studies

Several studies investigated the association between miR-34b/c rs4938723 polymorphism and the risk of several human cancers, but the findings remain inconclusive. To evaluate the impact of miR-34b/c rs4938723 on cancer risk, we performed a meta-analysis on all available studies including 12 361 cancer cases and 14 270 controls. Eligible studies were identified by searching PubMed, Web of Science, Scopus, and Google scholar databases. Pooled odds ratios with 95% confidence intervals were calculated in codominant, dominant, recessive, overdominant, and allele models to quantitatively estimate the association. The overall findings showed no significant association between miR-34b/c rs4938723 polymorphism and cancer risk in codominant, dominant, recessive, overdominant, and allele inheritance model. However, in stratified analysis by cancer types, the rs4938723 polymorphism significantly increased the risk of gastrointestinal cancer, hepatocellular carcinoma. In addition, the rs4938723 polymorphism was associated with decreased risk of esophageal squamous cell carcinoma, colorectal cancer, and acute lymphoblastic leukemia. The findings did not support an association between rs4938723 variant and digestive tract as well as gastric cancer. In summary, the findings of this meta-analysis indicated that the miR-34b/c rs4938723 polymorphism might be associated with some cancer development. Larger and well-designed studies are necessary to estimate this association in detail.

Association between Pri-miR-34b/c rs4938723 polymorphism and bladder cancer risk

Several studies examined the impact of miR-34b/c rs4938723 polymorphism and cancer risk, but the findings are inconsistent. However, no study has been conducted to inspect the impact of miR-34b/c polymorphism on bladder cancer. This study aimed to assess possible association between rs4938723 polymorphism and bladder cancer risk. This case-control study was done on 136 pathologically proven bladder cancer patients and 144 controls. Genotyping of Pri-miR-34b/c rs4938723 polymorphism was achieved by using the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Our findings did not show any statistically significant differences in genotype and allele frequencies between bladder cancer and controls. Larger sample sizes with diverse ethnicities are required to validate our findings.

Identifying a panel of genes/proteins/miRNAs modulated by arsenicals in bladder, prostate, kidney cancers

Arsenic and arsenic-derivative compounds, named as arsenicals, represent a worldwide problem for their effect on the human health and, in particular, for their capability to increase the risk of developing cancer such as kidney, bladder and prostate cancer. The main source of arsenical exposure is drinking water. Nowadays, it is well known that the chronic exposure to arsenicals leads to a series of epigenetic alterations that have a role in arsenic-induced effects on human health including cancer. Based on these observations, the aim of our study was to select by network analysis the genes/proteins/miRNAs implicated in kidney, bladder and prostate cancer development upon arsenical exposure. From this analysis we identified: (i) the nodes linking the three molecular networks specific for kidney, bladder and prostate cancer; (ii) the relative HUB nodes (RXRA, MAP3K7, NR3C1, PABPC1, NDRG1, RELA and CTNNB1) that link the three cancer networks; (iii) the miRNAs able to target these HUB nodes. In conclusion, we highlighted a panel of potential molecules related to the molecular mechanisms of arsenical-induced cancerogenesis and suggest their utility as biomarkers or therapeutic targets.

An updated meta-analysis of 23 case-control studies on the association between miR-34b/c polymorphism and cancer risk

The association between in microRNA-34b/c gene rs4938723 polymorphisms and cancer risk remains inconclusive. This meta-analysis was performed to analyze the association between microRNA-34b/c rs4938723 polymorphism and risk for cancer development. In total, 304 studies from PubMed, Embase, Web of Science, Wanfang, and Chinese National Knowledge Infrastructure databases were examined, and 23 studies were included in this meta-analysis. The 23 selected studies involved 10,812 cancer cases and 11,719 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure the strength of the association. Our results indicate a significant association between the rs4938723 polymorphism and cancer risk in the overdominant model (P heterogeneity = 0.018, OR = 1.093, and 95% CI = 1.015-1.177 for CT vs. CC/TT). Using a stratified subgroup analysis, rs4938723 polymorphisms were associated with an increased risk for hepatocellular carcinoma, but decreased risk for colorectal, gastric, and esophageal squamous cell cancer. These findings indicate that the rs4938723 gene is a susceptible locus for cancer.

Association between genetic polymorphisms of long non-coding RNA PRNCR1 and prostate cancer risk in a sample of the Iranian population

The aim of the present study was to determine whether there is an association between the long non-coding RNA (lncRNA) prostate cancer-associated non-coding RNA 1 (PRNCR1) polymorphisms and prostate cancer (PCa) risk in a sample of the Iranian population. This case-control study was performed on 178 patients with PCa and 180 subjects with benign prostatic hyperplasia (BPH). Genotyping assay was performed by polymerase chain reaction-restriction fragment length polymorphism. The findings indicated that the GG genotype of the rs13252298 A>G variant significantly increased the risk of PCa (odds ratio=3.49, 95% confidence interval: 1.79-6.81, P=0.0001) compared with AA+AG. As regards the rs1456315 G>A polymorphism, the AG genotype and G allele significantly increased the risk of PCa. As regards the rs7841060 T>G variant, the findings demonstrated that this TG genotype and the G allele significantly increased the risk of PCa. The rs7007694 T>C variant was not found to be associated with the risk of PCa. Haplotype analysis indicated that GTGA and GTGG significantly increased the risk of PCa compared with rs1456315A/rs7007694T/rs7841060T/rs13252298G (ATTG). The PRNCR1 variants were not found to be significantly associated with the clinicopathological characteristics of PCa patients. In conclusion, our findings support an association between PRNCR1 variants and the risk of PCa in a sample of the Iranian population.

Evaluation of a 3-base pair indel polymorphism within pre-microRNA-3131 in patients with prostate cancer using mismatch polymerase chain reaction-restriction fragment length polymorphism

The present study aimed to examine the impact of a 3-bp indel (rs57408770) polymorphism within the pre-microRNA (miR)-3131 polymorphism on prostate cancer (PCa) risk in a sample of an Iranian population. In total, 340 subjects, including 177 patients with PCa and 170 patients with benign prostatic hyperplasia, were enrolled in the present case-control study. A mismatch polymerase chain reaction-restriction fragment length polymorphism method was designed for genotyping the 3-bp indel (rs57408770) polymorphism. The present findings demonstrated that the indel variant significantly increased the risk of PCa in codominant [odds ratio (OR)=2.23, 95% confidence interval (CI)=1.13-4.37; P=0.021, insertion (ins)/ins vs. deletion (del)/del] and recessive (OR=2.33, 95% CI=1.25-4.36; P=0.009, ins/ins vs. del/del + del/ins). In conclusion, to the best of our knowledge, the present findings for the first time proposed that a 3-bp indel variant of miR-3131 may be a risk factor for susceptibility to PCa in a sample of an Iranian population. Further studies with different ethnicities and larger sample sizes are required to validate the present findings.

microRNAs in Cancer Susceptibility

microRNAs (miRNAs) are a small RNA species without protein-coding potential. However, they are key modulators of protein translation. Many studies have linked miRNAs with cancer initiation, progression, diagnosis, and prognosis, and recent studies have also linked them with cancer etiology and susceptibility, especially through single-nucleotide polymorphisms (SNPs). This review discusses some of the recent advances in miRNA-SNP literature-including SNPs in miRNA genes, miRNA target sites, and the processing machinery. In addition, we highlight some emerging areas of interest, including isomiRs and non-3'UTR focused miRNA-binding mechanisms that could provide further novel insight into the relationship between miR-SNPs and cancer. Finally, we note that additional epidemiological and experimental research is needed to close the gap in our understanding of the genotype-phenotype relationship between miRNA-SNPs and cancer.