Single Nucleotide Polymorphisms in miR-122 Are Associated with the Risk of Hepatocellular Carcinoma in a Southern Chinese Population

Circulating afamin positively correlated with the miR-122 expression and type 2 diabetes mellitus-related phenotype according to the duration of diabetes

Background

Afamin is a hepatokine that involves in glucose and lipids metabolism. miR-122 is mainly expressed in liver and involves in lipid and carbohydrate metabolism. This study aimed at investigating the circulating afamin, its correlation with type 2 diabetes mellitus (T2DM) and miR-122 gene expression in T2DM patients and healthy control subjects according to the duration of diabetes.

Methods

This case-control study included 220 participants, with 100 individuals serving as controls and 120 individuals diagnosed with type 2 diabetes mellitus (T2DM). The miR-122 gene expression was assessed using real-time PCR. The serum concentration of biochemical parameters such as glucose levels, lipid profile, and small-dense low-density lipoprotein (sdLDL) were measured using colorimetric kits. Circulating afamin and insulin levels were assayed using an ELISA kit. Glycated hemoglobin (HbA1c) was measured using capillary electrophoresis.

Results

Circulating afamin level was significantly higher in T2DM patients compared to the control group, (73.8 ± 10.8 vs. 65.9 ± 8.7, respectively; P < 0.001). Similarly, miR122 expression was significantly increased in T2DM patients compared to healthy control subjects (4.24 ± 2.01 vs. 1.00 ± 0.85, respectively; P < 0.001). Among patients diagnosed with T2DM, those with longstanding diabetes (>5 years) exhibited significantly higher levels of circulating afamin and miR-122 expression compared to individuals with a shorter duration of diabetes (≤5 years) (P < 0.05). Circulating afamin levels were significantly correlated with waist circumference, small-dense low-density lipoprotein (sdLDL), fasting blood sugar (FBS), insulin, resistance to insulin, and miR-122 expression, depending on the duration of the disease (P < 0.05). Furthermore, the performance of afamin as a diagnostic marker for T2DM was confirmed through receiver operating characteristic (ROC) analysis, yielding an area under the curve (AUC) of 0.7 (P < 0.001).

Conclusions

Circulating afamin involved in the T2DM-related complications and its concentration is positively correlated to the miR-122 expression, especially in patient with longstanding diabetes.

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.

The Effects of Single Nucleotide Polymorphisms in Cancer RNAi Therapies

Tremendous progress in RNAi delivery methods and design has allowed for the effective development of siRNA-based therapeutics that are currently under clinical investigation for various cancer treatments. This approach has the potential to revolutionize cancer therapy by providing the ability to specifically downregulate or upregulate the mRNA of any protein of interest. This exquisite specificity, unfortunately, also has a downside. Genetic variations in the human population are common because of the presence of single nucleotide polymorphisms (SNPs). SNPs lead to synonymous and non-synonymous changes and they occur once in every 300 base pairs in both coding and non-coding regions in the human genome. Much less common are the somatic mosaicism variations associated with genetically distinct populations of cells within an individual that is derived from postzygotic mutations. These heterogeneities in the population can affect the RNAi's efficacy or more problematically, which can lead to unpredictable and sometimes adverse side effects. From a more positive viewpoint, both SNPs and somatic mosaicisms have also been implicated in human diseases, including cancer, and these specific changes could offer the ability to effectively and, more importantly, selectively target the cancer cells. In this review, we discuss how SNPs in the human population can influence the development and success of novel anticancer RNAi therapies and the importance of why SNPs should be carefully considered.

A miR-182 variant and risk of hepatocellular carcinoma in a southern Chinese population

MicroRNAs (miRNAs) play important roles in the regulation of gene expression at the posttranscriptional level and are involved in human carcinogenesis. The aim of the current study was to investigate the associations between miR-182 single nucleotide polymorphisms and HCC risk in a southern Chinese population. In this case-control study of 863 HCC patients and 908 cancer-free controls, we performed genotyping of miR-182 rs4541843 and assessed its association with HCC risk. We found that individuals carrying the AG/AA genotypes of miR-182 rs4541843 were significantly associated with an increased risk of HCC compared with those carrying the GG genotype (adjusted odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.07–2.76, P = 0.026). In the stratified analysis, this increased risk was more pronounced in the subgroups of older individuals (adjusted OR = 1.98, 95% CI = 1.04–3.76, P = 0.037), males (adjusted OR = 1.81, 95% CI = 1.09–2.99, P = 0.021), and never drinkers (adjusted OR = 1.84, 95% CI = 1.03–3.30, P = 0.041). Our results suggested that miR-182 polymorphism rs4541843 may contribute to the susceptibility to HCC. Our findings require validation in further studies with larger sample sizes.

Association between polymorphisms in MicroRNA target sites of RAD51D genes and risk of hepatocellular carcinoma

RAD51D (RAD51L3) is a member of the RAD51 gene family which plays important roles in maintaining genomic stability and preventing DNA damage. This study is aimed to investigate the associations between RAD51D polymorphisms and the hereditary susceptibility of hepatocellular carcinoma (HCC). In this study we conducted a hospital-based case-control study including 805 cases (HCC patients) and 846 controls (nontumor patients) in Guangxi, China. A total of two Single-nucleotide polymorphisms (SNPs) rs12947947 and rs28363292 of RAD51D were selected and genotyped. Although we did not find two SNPs individually that had any significant main effect on risk of HCC, We found that the combined genotypes with 1-2 risk genotypes were associated with significantly increased overall risk of HCC (OR = 1.462, 95% CI = 1.050-2.036). According to the results of further stratification analysis, GT/GG genotype of rs28363292 increased HCC risk in zhuang people (OR = 3.913, 95% CI = 1.873-8.175) and nonhepatitis B virus (HBV) infection population (OR = 1.774, 95% CI = 1.060-2.969), the combined 1-2 risk genotypes increased the risk of HCC in zhuang people (OR = 2.817, 95% CI = 1.532-5.182) and non-HBV infected population (OR = 1.567, 95% CI = 1.042-2.358). Our results suggest that rs12947947 and rs28363292 polymorphisms may jointly contribute to the risk of HCC. Further large studies and functional studies are required to validate our findings.