HMGA2 gene polymorphisms and Wilms tumor susceptibility in Chinese children: a four-center case-control study

Association of deletion polymorphism rs10573247 in the HMGA2 gene with the risk of breast cancer: bioinformatic and experimental analyses

BACKGROUND

The high mobility group A2 (HMGA2) gene is expressed extensively during early embryonic development but is inactivated in adulthood, and it is also reactivated in various benign and malignant tumors, including breast cancer. We first assessed the potential functional significance of the unstudied deletion polymorphism rs10573247 at the 3'UTR of HMGA2 on miRNA binding using bioinformatic tools, and subsequently, the association between this polymorphism and breast cancer susceptibility was investigated.

MATERIALS AND METHODS

We applied the RNAhybrid tool to predict the functional effects of polymorphism rs10573247 located within the 3' UTR of the HMGA2 gene on miRNA binding. Then, following DNA extraction, 141 breast cancer patients and 123 healthy controls were genotyped for polymorphism rs10573247 using RFLP-PCR with the restriction enzyme Eam1104I.

RESULTS

Our bioinformatic data have shown that polymorphism rs10573247 is located in the region that serves as a potential target site for eight miRNAs binding. Among them, miR-3125 exhibited decreased binding affinity for the allele delTT (MFE = -21.8) when compared to the allele TT (MFE = -23.9), but miR-4476 increased binding affinity for the allele delTT (MFE = -22.4) compared to the allele TT (MFE = -22.2). In addition, our results showed that the genotype TT/delTT (p = 0.005) and the genotype delTT/delTT (p = 0.029) were significantly associated with an increased risk of developing breast cancer compared to the genotype TT/TT using RFLP-PCR.

DISCUSSION AND CONCLUSION

Our findings suggest that polymorphism rs10573247 may contribute to the risk of breast cancer through the functional effect of this polymorphism on miRNA binding.

HMGA2 rs968697 T > C polymorphism is associated with the risk of colorectal cancer

A genetic polymorphism (rs968697 T > C) in the HMGA2 gene has recently been linked to an increased risk of hepatoblastoma. However, no studies have been conducted to investigate the effect of the polymorphism on the risk of colorectal cancer (CRC). The study aimed to explore whether the rs968697 polymorphism had a significant impact on CRC risk. A total of 500 CRC patients and 500 age and gender matched healthy individuals were genotyped by using the SNaPshot method. Quantitative real-time PCR technology was used to detect the relative expression of the HMGA2 gene in 30 pairs of primary CRC and adjacent non-cancerous tissues. Results: HMGA2 rs968697 polymorphism was significantly associated with CRC risk [CC vs. TT: OR = 0.20, 95%CI = 0.06-0.70, P = 0.01; (CC + CT) vs. TT: OR = 0.71, 95%CI = 0.53-0.96, P = 0.02; CC vs. (CT + TT): OR = 0.21, 95%CI = 0.06-0.73, P = 0.01; C vs. T: OR = 0.67, 95%CI = 0.51-0.89, P < 0.01]. The analysis based on tumor stage indicated that the CRC patients with HMGA2 rs968697 C allele were less likely to have high-stage tumors. Furthermore, the genotype-tissue expression analysis revealed that the rs968697 CC genotype was linked to the low expression of HMGA2 gene. The in silico analysis revealed that the rs968697 polymorphism in the promoter region of the HMGA2 gene could influence transcription factor binding, including ATF6, DBP, CDPCR3, DR3, NRSF, PAX8, PPARA, SZF11, TAXCREB and POLR2A. In conclusion, our findings suggested that the HMGA2 rs968697 polymorphism was linked to CRC risk and could be used as a biomarker to detect CRC risk.

Association of HMGA2 Polymorphisms with Glioma Susceptibility in Chinese Children

Background

Glioma is a malignant central nervous system tumor in children, with poor outcomes and prognosis. HMGA2 is a proto-oncogene with increased expression in various malignancies.

Methods

We explored the association of HMGA2 polymorphisms with glioma susceptibility in Chinese children using a case-control study (191 cases, 248 controls). HMGA2 single nucleotide polymorphisms (rs6581658 A>G; rs8756 A>C; rs968697 T>C) were genotyped using PCR-based TaqMan.

Results

Increased glioma susceptibility was associated with rs6581658 A>G; AG (adjusted odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.13–2.58, P = 0.010) or GG (adjusted OR = 3.12, 95% CI = 1.26–7.74, P = 0.014) genotype carriers had significantly raised glioma risk compared with AA genotype carriers. The rs6581658 AG/GG (adjusted OR = 1.85, 95% CI = 1.25–2.73, P = 0.002) and AA/GG (adjusted OR = 2.58, 95% CI = 1.05–6.33, P = 0.038) genotypes were associated with an increased risk of glioma relative to the AA genotype. Subjects with 2–3 risk genotypes had a significantly elevated risk (adjusted OR = 1.93, 95% CI = 1.31–2.84, P = 0.001) relative to those with 0–1 risk genotype.

Conclusion

HMGA2 rs6581658 A>G is associated with glioma susceptibility in Chinese children.