Effects of single nucleotide polymorphisms in c-Myc on stable warfarin doses in patients with cardiac valve replacements

Possible key microRNAs and corresponding molecular mechanisms for atrial fibrillation

Objective:

We aimed to find crucial microRNAs (miRNAs) associated with the development of atrial fibrillation (AF), and then try to elucidate the possible molecular mechanisms of miRNAs in AF.

Methods:

The miRNA microarray, GSE68475, which included 10 right atrial appendage samples from patients with persistent AF and 11 samples from patients with normal sinus rhythm, was used for the analysis. After data preprocessing, differentially expressed miRNAs were screened using limma. Target genes of miRNAs were predicted using miRWalk2.0. We then conducted functional enrichment analyses for miRNA and target genes. Protein-protein interaction (PPI) network and module analyses for target genes were performed. Finally, transcription factors (TFs)-target genes regulatory network was predicted and constructed.

Results:

Seven genes, including CAMK2D, IGF2R, PPP2R2A, PAX6, POU3F2, YWHAE, and AP2A2, were targeted by TFs. Among these seven genes, CAMK2D (targeted by miR-31-5p), IGF2R (targeted by miR-204-5p), PAX6 (targeted by miR-223-3p), POU3F2 (targeted by miR-204-5p), YWHAE (targeted by miR-31-5p), and AP2A2 (targeted by miR-204-5p) belonged to the top 10 degree genes in the PPI network. Notably, MiR-204-5p, miR-31-5p, and miR-223-3p had more target genes. Besides, CAMK2D was enriched in some pathways, such as adrenergic signaling in cardiomyocytes pathway and cAMP signaling pathway. YWHAE was enriched in the Hippo signaling pathway.

Conclusion:

miR-31-5p played a crucial role in cardiomyocytes by targeting CAMK2D and YWHAE via cAMP and Hippo signaling pathways. miR-204 was involved in the progression of AF by regulating its target genes IGF2R, POU3F2, and AP2A2. On the other hand, miR-223-3p functioned in AF by targeting PAX6, which was associated with the regulation of apoptosis in AF. This study would provide a theoretical basis and potential therapeutic targets for the treatment of AF.

Association of CMYC polymorphisms with hepatoblastoma risk

BACKGROUND

Single-nucleotide polymorphisms (SNPs) in genes may affect gene expression and contribute to cancer susceptibility. This study aimed to explore the association between CMYC gene polymorphisms and hepatoblastoma risk.

METHODS

Hepatoblastoma patients and cancer-free controls were recruited and matched by age and sex. Genotypes were determined by TaqMan, and the strength of the association of interest was determined by calculating odds ratios (ORs) and 95% confidence intervals (CIs). The distributions of various CMYC genotypes among subjects were recorded, followed by analyses of associations between CMYC polymorphisms and hepatoblastoma risk.

RESULTS

A total of 213 hepatoblastoma patients and 958 cancer-free controls were enrolled. No significant associations between the CMYC rs4645943 and rs2070583 polymorphisms and hepatoblastoma risk were found (all P>0.05). In stratification analysis based on age, sex, and clinical stage, the CMYC rs4645943 and rs2070583 polymorphisms were not associated with hepatoblastoma susceptibility (all P>0.05).

CONCLUSIONS

Thus, the CMYC rs4645943 and rs2070583 polymorphisms were not associated with hepatoblastoma risk in the study cohort.

Effects of Polymorphisms in Myc-Related Genes on Bleeding Complications in Patients with Stable Warfarin Responses

Objectives

This study aimed to identify the possible effects of Myc and 8q24 polymorphisms on bleeding complications in patients who maintained international normalized ratio (INR) of 2.0-3.0 with warfarin therapy after cardiac valve replacement.

Methods

Twenty-five single nucleotide polymorphisms were analyzed, including VKORC1, CYP2C9, Myc, and 8q24. Univariate and multivariate analyses were conducted to evaluate the associations between genetic polymorphisms and bleeding complications. Attributable risk and the number needed to genotype (NNG) were also calculated to evaluate the potential clinical value of genotyping.

Results

We included 142 patients, among whom 21 experienced bleeding complications. Multivariate models showed that patients carrying the CC genotype of rs6983561 and the A allele of rs13281615 at 8q24 had 27.6- and 10.0-fold higher bleeding complications, compared with patients with the A allele and the GG genotype, respectively. For rs6983561, the attributable risk and NNG were 96.4% and 36.8, respectively, whereas, for rs13281615, the attributable risk and NNG were 90.0% and 8.3, respectively. Atrial fibrillation was associated with a 5.5-fold increased risk of bleeding complications. The AUROC value was 0.761 (95% CI 0.659-0.863, p<0.001), and the Hosmer–Lemeshow test showed that the fitness of the multivariate analysis model was satisfactory (χ²=0.846; 3 degrees of freedom; p=0.838).

Conclusions

Bleeding complications during warfarin therapy were associated with 8q24 polymorphisms and atrial fibrillation in patients with mechanical heart valves.