No association of hypoxia inducible factor-1α gene polymorphisms with breast cancer in North-West Indians

The Relation of VEGFA, VEGFR2, VEGI, and HIF1A Genetic Variants and Their Serum Protein Levels with Breast Cancer in Egyptian Patients

Breast cancer is the most common type of cancer in Egyptian females. Polymorphisms in the angiogenesis pathway have been implicated previously in cancer risk and prognosis. The aim of the current study was to determine whether certain polymorphisms in the genes of vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor receptor 2 (VEGFR2), vascular endothelial growth inhibitor (VEGI), and hypoxia-inducible factor-1α (HIF1A) associated with breast cancer development. The study included 154 breast cancer patients and 132 apparently healthy age-matched females as a control group. VEGFA rs25648 genotyping was performed using (ARMS) PCR technique; while VEGFR2 rs2071559, VEGI rs6478106, and HIF-1α rs11549465 were genotyped by the PCR-RFLP method. Serum levels of VEGF, VEGFR2, VEGI, and HIF1A proteins in breast cancer patients and controls were measured by ELISA. There was a significant association between the VEGFA rs25648 C allele and breast cancer risk (OR 2.5, 95% CI 1.7-3.6, p < 0.001). VEGFA rs25648 C/C genotype was statistically significantly higher in breast cancer patients vs. control (p < 0.001). Participants with the T/T and T/C VEGFR2 rs2071559 genotypes had 5.46 and 5 higher odds, respectively, of having breast cancer than those with the C/C genotype. For the VEGI rs6478106 polymorphism, there was a higher proportion of C allele in breast cancer patients vs. control (p = 0.003). Moreover, the C/C genotype of VEGI rs6478106 was statistically significantly higher in breast cancer patients vs. control (p = 0.001). There was no significant difference in genotypes and allele frequencies of HIF1A rs11549465 polymorphism between breast cancer cases and control individuals (p > 0.05). Serum levels of VEGFA, VEGI, and HIF1A were considerably greater in women with breast cancer than in the control (p < 0.001). In conclusion, the genetic variants VEGFA rs25648, VEGFR2 rs2071559, and VEGI rs6478106 revealed a significant association with increased breast cancer risk in Egyptian patients.

Association of Hypoxia-Inducible Factor 1α Gene Polymorphisms With Breast Cancer Susceptibility: A Meta-Analysis

PURPOSE

Overexpression of the hypoxia-inducible factor 1α (HIF1A) gene is significantly associated with different types of cancers, including breast cancer. In this study, the effects of single-nucleotide polymorphisms rs11549465, rs11549467, and rs2057482 of the HIF1A gene and their association with breast cancer were systematically investigated through meta-analysis.

MATERIALS AND METHODS

After a systematic review, nine case-control studies of the HIF1A rs11549465 C/T polymorphism, six case-control studies of the HIF1A rs11549467 G/A polymorphism, and one case-control study of the HIF1A rs2057482 C/T polymorphism were included in this meta-analysis. The summary pooled odds ratios with 95% CIs were evaluated to detect the relationship between HIF1A polymorphisms and breast cancer susceptibility.

RESULTS

Subgroup-stratified analyses showed that the T and TT genotypes of the HIF1A rs11549465 C/T polymorphism were significantly associated with increased breast cancer risk in the Asian population under three genetic models (allele, homozygous, and recessive). HIF1A rs11549467 G/A analyses indicated that the A and AA genotypes were significantly associated with increased breast cancer risk in the Asian population under allele and dominant models. However, no association with breast cancer was observed in the White population for the HIF1A rs11549465 C/T and rs11549467 G/A polymorphisms. In addition, the HIF1A rs2057482 C/T polymorphism showed no association with breast cancer under any genetic models or by ethnicity-stratified analyses.

CONCLUSION

The results of this meta-analysis suggested that the HIF1A rs11549465 C/T and rs1154946 G/A polymorphisms were significantly associated with increased breast cancer risk in the Asian population, but no associations were found in the White population. Thus, HIF1A could be an important biomarker for population-based breast cancer screening.

In silico pathway analysis based on chromosomal instability in breast cancer patients

BACKGROUND

Complex genomic changes that arise in tumors are a consequence of chromosomal instability. In tumor cells genomic aberrations disrupt core signaling pathways involving various genes, thus delineating of signaling pathways can help understand the pathogenesis of cancer. The bioinformatics tools can further help in identifying networks of interactions between the genes to get a greater biological context of all genes affected by chromosomal instability.

METHODS

Karyotypic analyses was done in 150 clinically confirmed breast cancer patients and 150 age and gender matched healthy controls after 72 h Peripheral lymphocyte culturing and GTG-banding. Reactome database from Cytoscape software version 3.7.1 was used to perform in-silico analysis (functional interaction and gene enrichment).

RESULTS

Frequency of chromosomal aberrations (structural and numerical) was found to be significantly higher in patients as compared to controls. The genes harbored by chromosomal regions showing increased aberration frequency in patients were further analyzed in-silico. Pathway analysis on a set of genes that were not linked together revealed that genes HDAC3, NCOA1, NLRC4, COL1A1, RARA, WWTR1, and BRCA1 were enriched in the RNA Polymerase II Transcription pathway which is involved in recruitment, initiation, elongation and dissociation during transcription.

CONCLUSION

The current study employs the information inferred from chromosomal instability analysis in a non-target tissue for determining the genes and the pathways associated with breast cancer. These results can be further extrapolated by performing either mutation analysis in the genes/pathways deduced or expression analysis which can pinpoint the relevant functional impact of chromosomal instability.

The evaluation of VEGF and HIF-1α gene polymorphisms and multiple sclerosis susceptibility

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease that leads to myelin sheath destruction. Hypoxia-inducible factor 1 (HIF-1) has several roles in cells, such as inducing inflammation and angiogenesis. Recently, several lines of evidence have indicated the role of the hypoxia response and the HIF-1 signaling pathway in an autoimmune disease such as MS. The present study aimed to evaluate the effects of HIF-1α gene polymorphisms and vascular endothelial growth factor (VEGF) (as a major target gene of HIF-1α) gene polymorphism on MS susceptibility.

METHODS

In total, 150 MS patients and 150 healthy age- and gender-matched people as a control group participated in the present study. The polymerase chain reaction-restriction fragment length polymorphism method was used for genotyping.

RESULTS

The results obtained showed that the CC genotype of the VEGF rs699947 polymorphism was significantly higher in the case group than in the control group (p = 0.004). Also, we showed a significant relationship between the VEGF rs699947 polymorphism and MS in a dominant inheritance model (p = 0.005). Regarding the VEGF rs699947 polymorphism allelic distribution, the C allele frequency was significantly higher in the control group than in the case group (71.3% versus 61%, respectively, p = 0.009) and decreased the MS susceptibility by 1.6-fold (odds ratio = 1.6, 95% confidence interval = 1.2-2.2). There was no significant difference between the two groups with respect to HIF-1α rs11549465 genotypic distribution. The HIF-1α C111A polymorphism was non-polymorphic in our study population, except in the case group where nine subjects carried the CA genotype.

CONCLUSIONS

We show a significant association between VEGF rs60047 polymorphism and MS susceptibility. However, our results do not show a significant association between MS and HIF-1α polymorphisms.

Association of hypoxia-inducible factor-1α (HIF1α) 1790G/A gene polymorphism with renal cell carcinoma and prostate cancer susceptibility: a meta-analysis

BACKGROUND

This meta-analysis was performed to evaluate the relationship between hypoxia-inducible factor-1α (HIF1α) 1790G/A gene polymorphism and the susceptibility to renal cell carcinoma (RCC) and prostate cancer (PCa).

METHODS

Association investigations were identified and included from the Embase, Cochrane Library and PubMed databases on March 1, 2018, and eligible investigations were analyzed by meta-analysis. Odds ratios (OR) were used to express the dichotomous data, and the 95% confidence intervals (CI) were also calculated.

RESULTS

In this meta-analysis, we found that the AA genotype of HIF1α 1790G/A was positively associated with the risk of RCC in overall populations, Caucasians, but not for Asians. G allele and GG genotype were not associated with the susceptibility of RCC in overall populations, Caucasians, and Asians. The G allele was negatively associated with PCa susceptibility in overall populations, Asians, but not for Caucasians. GG genotype was negatively associated with PCa susceptibility in Asians, but not for overall populations and Caucasians. HIF1α 1790G/A AA genotype was not associated with PCa susceptibility in overall populations of Caucasians or Asians.

CONCLUSION

AA genotype of HIF1α 1790G/A was positively associated with RCC risk in overall populations and Caucasians. Furthermore, the G allele was negatively associated with prostate cancer susceptibility in overall populations, Asians, and GG genotype was negatively associated with PCa susceptibility in Asians.

Polymorphisms in HIFs and breast cancer sutarsceptibility in Chinese women: a case-control study

Hypoxia-inducible factors (HIFs) play a crucial role in cancer progression. Several epidemiological studies have demonstrated that HIFs polymorphisms can influence the susceptibility of multiple cancers. However, the relationship of HIFs polymorphisms (rs11549467 and rs17039192) and breast cancer (BC) risk was still unknown. Thus, we performed a case-control study based on 560 BC patients and 583 healthy controls to explore the association between them. Our results indicated a boardline connection between HIF-1 rs11549467 and BC risk (AG compared with GG: OR = 1.61, 95% CI = 1.05-2.49, P=0.03; AG + AA compared with GG: OR = 1.64, 95% CI = 1.08-2.51, P=0.02; AG compared with GG + AA: OR = 1.61, 95% CI = 1.04-2.48, P=0.03; OR = 1.64, 95% CI = 1.09-2.45, P=0.02), while HIF-2 rs17039192 had no influence on breast cancer. Considered the comparison of sample size and potential heterogeneity of previous case-control studies, we concluded that HIF-1 rs11549467 has a marginal effect on BC risk. Further well-designed studies with larger sample size were required.

The association of the placental Hypoxia-inducible factor1-α polymorphisms and HIF1-α mRNA expression with preeclampsia

INTRODUCTION

Evidence has confirmed that placental/fetal hypoxia plays a key role in both endothelial cell dysfunction and PE pathogenesis. The aim of the present study was to investigate whether maternal/placental hypoxia-inducible factor1-α (HIF1-α) C1772T (rs11549465) and/or G1790A (rs11549467) polymorphisms and HIF1-α mRNA expression are associated with PE development.

METHODS

The blood samples of 203 PE and 202 control women and the placenta of 86 PE and 84 control women were collected after delivery. The HIF1-α polymorphisms were genotyped using PCR- RFLP method. The mRNA expression levels were measured by Quantitative Real -Time PCR.

RESULTS

The present study found no association between maternal HIF1-α rs11549465 and rs11549467 and placental rs11549467 polymorphisms and PE. However, the placental rs11549465 polymorphism was associated with PE in the dominant model. The CT/GG combined genotypes and TG haplotype of placental rs11549465 and rs11549467 polymorphisms were associated with higher risk of PE. The HIF1-α mRNA expression was 3-fold higher in the PE women. The rs11549465 TT genotype was associated with higher HIF1-α mRNA expression in PE women and in total population and rs11549467 GA genotype was associated with higher mRNA expression in total population. The relative mRNA expression of HIF1-α gene was higher in presence of CC/GA, TT/GG and TT/GA combined genotypes.

CONCLUSION

This study found an association between placental but not maternal HIF1-α rs11549465 polymorphism and PE in the dominant model. The HIF1-α mRNA expression was higher in the placenta of PE women and was associated with rs11549465 and rs11549467 polymorphisms.

Does Hypoxia-Inducible Factor -1 α (HIF-1α) C1772T polymorphism predict short-term prognosis in patients with oral squamous cell carcinoma (OSCC)?

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a cancer of the oral cavity that is a major health problem in India. There is an urgent need to identify biomarkers that have prognostic significance. We studied HIF-1α levels as well as single-nucleotide polymorphism of HIF-1α gene in cancer and healthy controls.

METHODS

Fifty newly diagnosed OSCC patients and 50 age and sex-matched healthy control were included in the study. Serum concentrations of HIF-1α were measured by sandwich ELISA; whereas HIF-1α gene polymorphism study was performed using restriction enzyme digestion by HpH I.

RESULTS

The major genotype observed was CC genotype in both control (84%) and patients (86%) followed by CT genotype (control 16%, cases 14%). CT genotype led to more aggressive tumors. On subgroup analysis based on prognosis, the median overall survival of patients who were treatment responders was 488 days (16.2 months) and that of the patients with progressive disease was 365 days (12.1 months). The patients who expired during the study observation period had median survival of 330 days (11 months).

CONCLUSION

Our study showed that CT genotype for C1772T polymorphism of HIF-1α predisposes to aggressive tumor phenotype in patients with OSCC. Moreover, patients with CT genotype had poor survival rate as compared to CC genotype. A cut-off value of 460 pg/mL of HIF-1α can help to segregate patients with OSCC from healthy controls.

Neuroprotective mechanism of HIF-1α overexpression in the early stage of acute cerebral infarction in rats

The present study aimed to explore the expression and neuroprotective mechanism of hypoxia inducible factor (HIF-1α) in the brain tissue of a rat model of early acute cerebral infarction. A total of 64 Sprague Dawley rats were randomly divided into surgery and sham groups and the model of focal cerebral infarction was established by the suture-occluded method. In the sham group, blood vessels were separated but not occluded. Rats in the surgery and sham groups were subdivided into eight groups (n=4/group). Blood samples was collected at 8 time points including 30 min and 1, 3, 6, 12, 48, 24 and 72 h, respectively, and HIF-1α content was detected using ELISA. Brain tissues of rats in all groups were harvested following blood collection. HIF-1α protein expression was detected by immunohistochemistry and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling was used to analyze the brain cell apoptosis index. ELISA results demonstrated that rats in the surgery group began to express HIF-1α within 30 min, and HIF-1α expression levels gradually increased, peaking at 12 h. HIF-1α expression levels were significantly increased in the surgery group at all time points, as compared with the sham group (P<0.05). The concentration of HIF-1α decreased rapidly in 12 h. At various time points, HIF-1α protein expression in the brain tissue of rats in the sham group was negative. HIF-1α protein expression was significantly increased in the surgery group (P<0.05), peaking at 12 h, and decreasing after this point. As compared with the sham group, the apoptosis indices of the brain tissue of rats in the surgery group exhibited a gradual increasing trend with significant decreases observed after 12 h (P<0.05). Intra-group comparison of all indices in the surgery group, indicated that there was a statistically significant difference between postoperative 12 h and other time points (P<0.05). In conclusion, the present study demonstrated that HIF-1α was highly expressed in the brain tissue of rat models of early acute cerebral infarction. The results also indicated that HIF-1α significantly reduced the apoptosis of infarcted cells, suggesting that HIF-1α may have a neuroprotective role in early acute cerebral infarction.