Detection of a 4-bp Insertion/deletion Polymorphism within the Promoter of EGLN2 Using Mismatch PCR-RFLP and Its Association with Susceptibility to Breast Cancer

A Novel PCR Method for Detecting ACE Gene Insertion/Deletion Polymorphisms and its Clinical Application

Background

Angiotensin-converting enzyme (ACE) plays a major role in blood pressure regulation and cardiovascular homeostasis. The wide distribution and multifunctional properties of ACE suggest it’s involvement in various pathophysiological conditions.

Results

In this study, a novel visual detection method for ACE I/D polymorphisms was designed by integrating direct PCR without the need for DNA extraction using gold magnetic nanoparticles (GMNPs)-based lateral flow assay (LFA) biosensor. The entire detection procedure could enable the genotyping of clinical samples in about 80 min. The detection limit was 0.75 ng and results could be obtained in 5 min using the LFA device. Three hundred peripheral blood samples were analyzed using the direct PCR-LFA system and then verified by sequencing to determine accuracy and repeatability. A clinical preliminary study was then performed to analyze a total of 633 clinical samples.

Conclusions

After grouping based on age, we found a significant difference between the genotypes and the age of patients in the CHD group. The introduction of this method into clinical practice may be helpful for the diagnosis of diseases caused by large fragment gene insertions/deletions.

Association of EGLN2 rs10680577 Polymorphism with the Risk and Clinicopathological Features of Patients with Prostate Cancer

Several studies have evaluated the association between EGLN2 4-bp insertion/deletion (ins/del) polymorphism (rs10680577) and many cancers. However, up to date, no study has inspected the impact of rs10680577 polymorphism on prostate cancer (PCa) risk. This case-control study was achieved on 170 pathologically confirmed PCa patients and 196 cancer free men to inspect whether rs10680577 variant is related to the risk and clinicopathological features of patients with PCa. Genotyping was performed by mismatched polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The findings did not support an association between the variant with the risk and clinicopathological characteristics of PCa patients. When we pooled our results with six preceding studies, the findings suggested that rs10680577 variant significantly augmented the risk of overall cancer in heterozygous (OR=1.38, 95 % CI=1.26-1.52, p<0.00001, ins/del vs ins/ins), homozygous (OR=1.66, 95 % CI=1.05-2.61, p=0.029, del/del vs ins/ins), codominant (OR=1.44, 95%CI=1.32-1.58, p<0.00001, ins/del+del/del vs ins/ins), and allele (OR=1.32, 95%CI=1.18-1.49, p<0.00001, del vs ins) genetic models. Additional well designed studies with larger sample sizes are necessary to confirm our findings.

The Relationship between Pre-miR-3131 3-bp Insertion/Deletion Polymorphism and Susceptibility and Clinicopathological Characteristics of Patients with Breast Cancer

Aims

This study aimed at examining the effect of 3-bp pre-miR-3131 insertion/deletion (ins/del) polymorphism on Breast Cancer (BC) risk.

Objectives

Totally 403 women including 199 BC patients and 204 women who have no cancer were included in this case-control study. Genotyping of miR-3131 3-bp ins/del polymorphism was performed by mismatch PCR-RFLP method.

Methods

The findings expressed that the pre-miR-3131 3-bp ins/del variant was not related to the risk of BC in all genetic tested models. While, the ins/del genotype was related to late onset BC (OR=2.53, 95%CI=1.27-4.84, p=0.008).

Results

Pooled results from the meta-analysis indicated to that the pre-miR-3131 ins/del is related to with an increased risk of cancer in heterozygous (OR=1.26, 95%CI=1.06-1.51, p=0.01), dominant (OR=1.33, 95%CI=1.14-1.54, p=0.0002), and allele (OR=1.24, 95%CI=1.06-1.45, p=0.006) genetics models.

Conclusion

It is concluded that, our findings did not support a relationship between pre-miR-3131 ins/del polymorphism and the risk of BC. While, this variant was significantly related to late onset BC. Combined results of this study with previous studies indicated that this polymorphism increased the risk of cancer. More studies in a study with larger population with variety of ethnicities are required to verify our findings.

Association between an indel polymorphism within the distal promoter of EGLN2 and cancer risk: An updated meta-analysis

Background

The association between a 4‐bp indel polymorphism (rs10680577) within the distal promoter of EGLN2 and cancer risk has been investigated by several case–control studies in recent years, but investigation results were inconsistent. Thus, a systematic assessment of the association was performed based on a literature review and pooled analysis.

Methods

Two investigators independently retrieved relevant studies from PubMed, Chinese National Knowledge Infrastructure (CNKI), Embase, and Google Scholar. The fixed or random effects model was selected to calculate odds ratios (ORs) with 95% confidence intervals (CIs) based on heterogeneity level. All analyses including heterogeneity assessment, subgroup analysis, sensitivity analysis, and publication bias assessment were performed using RevMan 5.3 software and Stata 12.0 software.

Results

A total of six relevant studies with 3,406 cases and 5,147 controls were included in the final analysis. The overall pooled analysis showed that EGLN2 rs10680577 polymorphism was significantly associated with cancer risk under all genetic models. However, subgroup analysis based on cancer type showed that the polymorphism was significantly associated with the risk of digestive system cancer under all genetic models, and with the risk of lung cancer under dominant model, heterozygote comparison model, and allele comparison model. Subgroup analysis based on population sources showed a significant association in Chinese population under all genetic models.

Conclusion

The present result suggests that EGLN2 rs10680577 polymorphism is associated with cancer risk, and may act as a promising predictive biomarker for cancer risk, especially in Chinese population. However, further well‐designed studies are warranted to confirm these results.