The SNP rs4846048 of MTHFR enhances the cervical cancer risk through association with miR-522: A preliminary report

A Functional Variant rs2072915 is Associated with the Susceptibility and Mortality of Cervical Squamous Cell Carcinoma

Purpose

Genetic variant has been demonstrated to be a risk factor for the occurrence and outcome of cervical squamous cell carcinoma (CSCC). From previous genome wide association studies, 6p21.32 has been identified as a susceptibility locus of CSCC. The purpose of this study was to investigate the association of a polymorphism rs2072915 located in 6p21.32 with the risk of CSCC and examine the potential mechanism of the rs2072915 in CSCC pathogenesis.

Patients and Methods

The rs2072915 was genotyped using polymerase chain reaction (PCR)-restriction fragment length polymorphism. miR-637 and RXRB mRNA expression levels in CSCC patients were examined using quantitative PCR. miR-637 target site was determined using the dual-luciferase reporter assay.

Results

The rs2072915 was associated with a significantly increased risk (AA vs TT: adjusted OR = 2.48, 95% CI, 1.57–3.94, P < 0.001; AT/AA vs TT: adjusted OR = 1.38, 95% CI, 1.06–1.80, P = 0.018; A vs T: adjusted OR = 1.49, 95% CI, 1.21–1.84, P < 0.001, respectively) and shorter survival time of CSCC (P = 0.03). Patients with the rs2072915 AA genotype displayed lower levels of RXRB that is a target of miR-637.

Conclusion

These findings suggest that the rs2072915 T > A change might augment the binding energy of miR-637 to RXRB, result in lower levels of RXRB, and thus contribute to the risk of CSCC.

Association analysis of maternal MTHFR gene polymorphisms and the occurrence of congenital heart disease in offspring

BACKGROUND

Although many studies showed that the risk of congenital heart disease (CHD) was closely related to genetic factors, the exact pathogenesis is still unknown. Our study aimed to comprehensively assess the association of single nucleotide polymorphisms (SNPs) of maternal MTHFR gene with risk of CHD and its three subtypes in offspring.

METHODS

A case-control study involving 569 mothers of CHD cases and 652 health controls was conducted. Thirteen SNPs were detected and analyzed.

RESULTS

Our study showed that genetic polymorphisms of maternal MTHFR gene at rs4846052 and rs1801131 were significantly associated with risk of CHD in the homozygote comparisons (TT vs. CC at rs4846052: OR = 7.62 [95%CI 2.95-19.65]; GG vs. TT at rs1801131: OR = 5.18 [95%CI 2.77-9.71]). And six haplotypes of G-C (involving rs4846048 and rs2274976), A-C (involving rs1801133 and rs4846052), G-T (involving rs1801133 and rs4846052), G-T-G (involving rs2066470, rs3737964 and rs535107), A-C-G (involving rs2066470, rs3737964 and rs535107) and G-C-G (involving rs2066470, rs3737964 and rs535107) were identified to be significantly associated with risk of CHD. Additionally, we observed that a two-locus model involving rs2066470 and rs1801131 as well as a three-locus model involving rs227497, rs1801133 and rs1801131 were significantly associated with risk of CHD in the gene-gene interaction analyses. For three subtypes including atrial septal defect, ventricular septal defect and patent ductus arteriosus, similar results were observed.

CONCLUSIONS

Our study indicated genetic polymorphisms of maternal MTHFR gene were significantly associated with risk of fetal CHD in the Chinese population. Additionally, there were significantly interactions among different SNPs on risk of CHD. However, how these SNPs affect the development of fetal heart remains unknown, and more studies in different ethnic populations and with a larger sample are required to confirm these findings.

Targeting of ΔNp63α by miR-522 promotes the migration of breast epithelial cells

The TP63 gene, which encodes the p63 protein, is involved in multiple biological processes, including embryonic development and tumorigenesis. ΔNp63α, the predominant isoform of p63 in epithelial cells, acts as an oncogene in early-stage tumors, but paradoxically acts as a potent antimetastatic factor in advanced cancers. Here, we report that ΔNp63α is a direct target of hsa-miR-522 (miR-522). Induced expression of miR-522 reduced the levels of ΔNp63α, predisposing breast epithelial cells to a loss of epithelial and acquisition of mesenchymal morphology, resulting in accelerated collective and single-cell migration. Restoration of ΔNp63α repressed miR-522-induced migration. Interestingly, overexpression of miR-522 did not affect breast epithelial cell proliferation, suggesting that miR-522 acts specifically through ΔNp63α in this context. Furthermore, expression of miR-522-3p and p63 was negatively correlated in human cancer samples. Thus, miR-522 might be a causative factor for breast tumorigenesis and cancer metastasis. In summary, our results reveal a novel miR-522/p63 axis in cell migration and thus suggest a potential strategy for therapeutic treatment of cancer metastasis.

Associations of the MTHFR rs1801133 polymorphism with gastric cancer risk in the Chinese Han population

In recent years, increasing evidence has implicated the importance of mutations in the MTHFR gene in the risk of gastric cancer risk. A single nucleotide polymorphism (SNP) in the MTHFR gene (rs1801133) may serve a critical role in gastric cancer. A hospital-based case-controlled study was performed to assess the risk of the rs1801133 polymorphism on gastric cancer. A total of 307 patients with gastric cancer and 560 patients in the control group were recruited. Genomic DNA was extracted from peripheral blood and genotyped for rs1801133 using the ligase detection reaction. The relationship between rs1801133 and gastric cancer risk was evaluated by unconditional logistical regression analysis. The rs1801133-TT genotype was associated with a borderline significantly decreased risk of gastric cancer [(TT vs. CC, adjusted odds ratio (OR)=0.54, 95% confidence intervals (CI)=0.35-0.83; P=0.006; CT vs. CC, adjusted OR=0.59, 95% CI=0.44-0.79, P<0.001; and TT/CT vs. CC, adjusted OR=0.61, 95% CI=0.44-0.83, P=0.001), and further analysis showed the relationship was evident amongst older patients and patients who never drank alcohol. The C>T mutation at rs1801133 of the MTHFR gene was associated with a decreased risk of gastric cancer in older individuals and those who never drink.

The SNP rs4846048 of MTHFR enhances the cervical cancer risk through association with miR-522: A preliminary report

BACKGROUND

The present research was designed to explore the association between single nucleotide polymorphisms (SNPs) at the 3'-untranslated region (3'-UTR) of methylenetetrahydrofolate reductase (MTHFR) and the risk of cervical cancer (CC).

METHODS

From May 2015 to October 2016, a total of 197 patients (diagnosed with CC and precancerous lesions, and underwent surgical treatments) were enrolled in the study. Meanwhile, a total of 80 healthy cases were used as the controls. PCR-DNA analysis was used to explore the genotype of the SNPs (rs4846048 and rs55763075) of the MTHFR 3'-UTR as well as the association between allelic frequencies and the CC risk. Then, the role of rs4846048 SNPs in the association of microRNA-522 (miR-522) and MTHFR was evaluated through luciferase reporter assay. Meanwhile, the modulatory influence of miR-522 on cell apoptosis and viability of Hela cells was also detected by flow cytometry and MTT assay.

RESULTS

The rs4846048 AG and G allele frequencies were significantly higher in CC subgroup compared with the control group. Methylenetetrahydrofolate reductase rs4846048 A/G alleles contributed to miR-522 binding, and miR-522 negatively modulated the expressions of MTHFR. Furthermore, miR-522 overexpression increased cell viability but decreased apoptotic cells in Hela cells.

CONCLUSION

The preliminary report revealed that the SNP rs4846048 of MTHFR enhanced the risk of CC through association with miR-522, which further regulated cell viability and apoptosis in Hela cells.