Hypoxia-inducible factor 1α polymorphisms and early-stage cervical cancer

Gene expression and oxidative stress markers profile associated with toxic metals in patients with renal cell carcinoma

BACKGROUND

Toxic metals are associated with cancer progression. Studies have reported the relation between some toxic metals and renal cell carcinoma (RCC).

METHODS AND RESULTS

Blood levels of Cd and Pb were determined in 94 RCC patients (RCC group) and 91 matched controls as well as blood level of malondialdehyde (MDA) and catalase (CAT) activity as markers of oxidative stress and antioxidant, respectively. Gene expression of MAP kinase pathway (P38 and JNK), hypoxia-inducible factor 1-alpha (HIF1α), vascular endothelial growth factor (VEGF), cytochrome C oxidase subunit 6 (COX6), metallothionein (MT2A), and heat shock protein (HSP90AA1) were evaluated in the obtained tissue specimens. Blood Cd and Pb levels were significantly higher in RCC group comparing to control group with preferential significant increase of Cd in chromophobe RCC (chRCC) sub-type. MDA level was significantly higher and CAT activity was lower in the RCC compared to controls. The difference was evident only in chRCC. The expressions of genes were significantly increased in the cancer tissues than in non-cancerous tissues in RCC sub-types and there was a significant correlation between Cd levels and expression of genes VEGF, MT2A, P38 and JNK in chRCC group. Immunohistochemical staining of clear cell RCC tissues shows a marked expression of VEGF and HIF-1α.While COX6 staining show marked expression in chRCC.

CONCLUSIONS

There is a positive correlation between Cd toxicity and the development of RCC, especially chRCC sub-type. Cd is strongly incriminated in the pathogenesis of chRCC through the effort on some genes and oxidative stress markers.

Correlation between hypoxia-inducible factor-1α C1772T/G1790A polymorphisms and head and neck cancer risk: a meta-analysis

Objective

This meta-analysis was implemented to evaluate the association between hypoxia-inducible factor-1α (HIF-1α) C1772T/G1790A polymorphisms and susceptibility to head and neck cancer (HNC).

Material and methods

This meta-analysis has been registered on PROSPERO platform (CRD42021257309). The PubMed, Embase and Web of Science databases were searched to retrieve eligible published papers. STATA software was used to calculate the pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to assess the correlation strength.

Results

Our results demonstrated that the HIF-1α C1772T polymorphism was significantly related to an increased HNC risk (OR = 2.27, 95% CI = 1.17–4.42 for the homozygous model; OR = 11.53, 95% CI = 1.11–120.4 for the recessive model), especially in Caucasians (OR = 2.16, 95% CI = 1.09–4.27 for the homozygous model; OR = 2.28, 95% CI = 1.15–5.51 for the recessive model). Similarly, a remarkable correlation was discovered between the G1790A polymorphism and HNC risk (OR = 72.11, 95% CI = 2.08–2502.4 for the homozygous model; OR = 58.05, 95% CI = 1.70–1985.77 for the recessive model). Moreover, in the subgroup analysis by source of controls, a statistically significant correlation was discovered in the population-based (PB) subgroup (OR = 9.43, 95% CI = 1.20–73.9 for allelic model; OR = 72.11, 95% CI = 2.08–2502.4 for the homozygous model; OR = 3.22, 95% CI = 1.28–8.08 for the heterozygous model; OR = 7.83, 95% CI = 1.48–41.37 for the dominant model; OR = 58.05, 95% CI = 1.70–1985.8 for the recessive model) but not in the hospital-based (HB) subgroup.

Conclusion

Our study found that both HIF-1α C1772T and G1790A polymorphisms might be a higher risk of HNC, especially in the Caucasian group with the C1772T polymorphism.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02324-0.

HIF-1α rs11549465 C>T polymorphism contributes to increased cancer susceptibility: Evidence from 49 studies

HIF-1α (hypoxia-inducible factor-1α) is a transcriptional factor that participates in the regulation of oxygen homeostasis. Despites numbers of case-control studies working on this area, the actual relationship of HIF-1α gene generic variant rs11549465 C>T imposing on cancer susceptibility remains unveiled. To get a better understanding of such relationship, this meta-analysis was carried out by incorporating all eligible case-control studies. Qualified articles were acquired from PubMed, CNKI, EMBASE, PMC, and Wanfang database update to April 2019. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were employed to estimate the relationship of interest. Heterogeneity tests, sensitivity analyses and publication bias assessments were also carried out to ensure the strength of our conclusion. A total of 46 articles with 49 studies including 12920 cases and 13363 controls were included. The results indicated that HIF-1α rs11549465 C>T was significantly related to the increased risk of overall cancer under four genetic models (TT vs. CC: OR=2.06, 95% CI=1.34-3.16; TT vs. CC/CT: OR=2.42, 95% CI=1.60-3.65; CT/TT vs. CC: OR=1.21, 95% CI=1.04-1.40; T vs. C: OR=1.29, 95% CI=1.12-1.48). Furthermore, enhanced cancer risk was detected after stratification by cancer type, ethnicity, the source of controls and HWE. These results suggest that HIF-1α rs11549465 C>T polymorphism may predispose to cancer susceptibility.

A pilot study of gonadotropin-releasing hormone agonist combined with aromatase inhibitor as fertility-sparing treatment in obese patients with endometrial cancer

Objective

This study aims to evaluate the effects and pregnancy outcomes of gonadotropin-releasing hormone agonist (GnRH agonist) combined with aromatase inhibitor (AI) in preserving the fertility of obese women with grade 1 endometrial cancer (EC).

Methods

This study recruited obese EC patients who wished to preserve their fertility. The treatment regimen consisted of intramuscular GnRH agonist 3.75 mg every 4 weeks and oral AI 2.5 mg daily. The maintenance regimen was the same as the initial treatment regimen. Primary outcomes included response rate, time to complete response (CR), and time to recurrence; pregnancy outcomes included the time to pregnancy, pregnancy rate and live birth rate.

Results

Six obese patients with EC were included in this study, with the age (mean±standard deviation [SD]) of 30.5±3.3 years and body mass index (mean±SD) of 35.0±1.4 kg/m². CR rate was 100%, and time to CR was 3–6 months. None of the patients had recurrence after a median follow-up of 4.0 years (range, 1.3–7.0 years). The most common side effects were menopause-like symptoms. Among these patients, no weight gain was observed during treatment. The pregnancy rate and live birth rate was 50.0% and 75.0%, respectively, with a median time to pregnancy of 2.4 years (range, 1.0–5.5 years).

Conclusion

The combination of GnRH agonist and AI demonstrated promising long-term effect in young obese EC patients who wished to preserve their fertility. No weight gain side effects were observed. Further studies with a larger sample size are needed to fully evaluate this novel treatment regimen.

Association of the hypoxia-inducible factor-1α (HIF-1α) gene polymorphisms with prognosis in ovarian clear cell carcinoma

Background

Ovarian clear cell carcinoma (OCCC) is the second most common ovarian cancer after serous carcinoma in Japan. OCCC has a more unfavorable clinical outcome due to a poor response to platinum-based chemotherapy, compared with serous carcinoma. Hypoxia inducible factor-1α (HIF-1α) is a key regulator of cellular response to hypoxia and plays an important role in tumor growth, and HIF-1α gene single-nucleotide polymorphisms (SNPs) adversely affect the outcome in some cancers. Herein, we investigated the association of the HIF-1α gene SPNs with clinical outcome in OCCCs. Eighty-nine patients with OCCC were recruited in whom pathological diagnosis was confirmed with surgically resected specimen.

Results

The SNPs of C1772T and G1790A in the HIF-1α gene occurred in 23.6 and 3.3% of the patients, respectively. In the univariate analysis, overall survival was associated with stage and surgical residual tumor but not with the SNPs C1772T, G1790A, C1772T and/or G1790A. In the multivariate survival analysis, a significant association was observed between outcome and FIGO stage and/or surgical residual tumor; however, no association was obtained between HIF-1α gene SNPs and these factors.

Conclusion

In conclusion, unlike the other cancers in which HIF-1α gene SNPs were demonstrated to be associated with the outcome, OCCC prognosis may not be affected by HIF-1α gene SNPs. Further studies need to be performed to clarify the association of HIF-1α expression with the unfavorable prognosis in OCCCs, in terms of transcriptional/translational activity, nuclear translocation of the protein, and protein degradation.

Six months response rate of combined oral medroxyprogesterone/levonorgestrel-intrauterine system for early-stage endometrial cancer in young women: a Korean Gynecologic-Oncology Group Study

OBJECTIVE

To evaluate the efficacy of combined oral medroxyprogesterone acetate (MPA)/levonorgestrel-intrauterine system (LNG-IUS) treatment and to compare the diagnostic accuracy of endometrial aspiration biopsy with dilatation & curettage (D&C) in young women with early-stage endometrial cancer (EC) who wished to preserve their fertility.

METHODS

A prospective phase II multicenter study was conducted from January 2012 to January 2017. Patients with grade 1 endometrioid adenocarcinoma confined to the endometrium were treated with combined oral MPA (500 mg/day)/LNG-IUS. At 3 and 6 months of treatment, the histologic change of the endometrial tissue was assessed. The regression rate at 6 months treatment and the consistency of the histologic results between the aspiration biopsy and the D&C were evaluated.

RESULTS

Forty-four patients were enrolled. Nine voluntarily withdrew and 35 patients completed the protocol treatment. The complete regression (CR) rate at 6 months was 37.1% (13/35). Partial response was shown in 25.7% of cases (9/35). There were no cases of progressive disease and no treatment-related complications. A comparison of the pathologic results from aspiration biopsy and D&C was carried out for 33 cases. Fifteen cases were diagnosed as "EC" by D&C. Among these, only 8 were diagnosed with EC from aspiration biopsy, yielding a diagnostic concordance of 53.3% (κ=0.55).

CONCLUSION

Combined oral MPA/LNG-IUS treatment for EC showed 37.1% of CR rate at 6 months. Considering the short treatment periods, CR rate may be much higher if the treatment continued to 9 or 12 months. So, this treatment is still a viable treatment option for young women of early-stage EC. Endometrial aspiration biopsy with the LNG-IUS in place is less accurate than D&C for follow-up evaluation of patients undergoing this treatment.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01594879.

PGE2 promotes breast cancer-associated lymphangiogenesis by activation of EP4 receptor on lymphatic endothelial cells

Background

Lymphatic metastasis, facilitated by lymphangiogenesis is a common occurrence in breast cancer, the molecular mechanisms remaining incompletely understood. We had earlier shown that cyclooxygenase (COX)-2 expression by human or murine breast cancer cells promoted lymphangiogenesis and lymphatic metastasis by upregulating VEGF-C/D production by tumor cells or tumor-associated macrophages primarily due to activation of the prostaglandin receptor EP4 by endogenous PGE2. It is not clear whether tumor or host-derived PGE2 has any direct effect on lymphangiogenesis, and if so, whether EP4 receptors on lymphatic endothelial cells (LEC) play any role.

Methods

Here, we address these questions employing in vitro studies with a COX-2-expressing and VEGF-C/D-producing murine breast cancer cell line C3L5 and a rat mesenteric (RM) LEC line and in vivo studies in nude mice.

Results

RMLEC responded to PGE2, an EP4 agonist PGE1OH, or C3L5 cell-conditioned media (C3L5-CM) by increased proliferation, migration and accelerated tube formation on growth factor reduced Matrigel. Native tube formation by RMLEC on Matrigel was abrogated in the presence of a selective COX-2 inhibitor or an EP4 antagonist. Addition of PGE2 or EP4 agonist, or C3L5-CM individually in the presence of COX-2 inhibitor, or EP4 antagonist, restored tube formation, reinforcing the role of EP4 on RMLEC in tubulogenesis. These results were partially duplicated with a human dermal LEC (HMVEC-dLyAd) and a COX-2 expressing human breast cancer cell line MDA-MB-231. Knocking down EP4 with shRNA in RMLEC abrogated their tube forming capacity on Matrigel in the absence or presence of PGE2, EP4 agonist, or C3L5-CM. RMLEC tubulogenesis following EP4 activation by agonist treatment was dependent on PI3K/Akt and Erk signaling pathways and VEGFR-3 stimulation. Finally in a directed in vivo lymphangiogenesis assay (DIVLA) we demonstrated the lymphangiogenic as well as angiogenic capacity of PGE2 and EP4 agonist in vivo.

Discussion/conclusions

These results demonstrate the roles of tumor as well as host-derived PGE2 in inducing lymphangiogenesis, at least in part, by activating EP4 and VEGFR-3 on LEC. EP4 being a common target on both tumor and host cells contributing to tumor-associated lymphangiogenesis reaffirms the therapeutic value of EP4 antagonists in the intervention of lymphatic metastasis in breast cancer.

Clinicopathological characteristics of gynecological cancer associated with hypoxia-inducible factor 1α expression: a meta-analysis including 6,612 subjects

BACKGROUND

Gynecological cancer is characterized by tumor hypoxia. However, the role of hypoxia-inducible factor 1α (HIF-1α) in gynecological cancer remains unclear.

METHOD

Electronic databases including Cochrane Library, PUBMED, Web of Knowledge and clinical trial registries were searched from inception through October 2014 for published, case-control studies assessing the association between HIF-1α and the clinicopathological characteristics of gynecological cancer. We pooled results from 59 studies using fixed or random-effects models and present results as odds ratios (ORs) following the PRISMA guidelines.

RESULTS

Our meta-analysis, which included 6,612 women, demonstrated that the expression of HIF-1α was associated with the clinicopathological characteristics of gynecological cancer. The expression of HIF-1α in cancer or borderline tissue was significantly higher than that in normal tissue (cancer vs. normal: odds ratio (OR) =9.59, 95% confidence interval (CI): 5.97, 15.39, p<0.00001; borderline vs. normal: OR=4.13, 95% (CI): 2.43, 7.02, p<0.00001; cancer vs. borderline: OR=2.70, 95% (CI): 1.69, 4.31, p<0.0001). The expression of HIF-1α in III-IV stage or lymph node metastasis was significantly higher than that in I-II stage or that without lymph node metastasis, respectively (OR=2.66, 95% (CI): 1.87,3.79, p<0.00001; OR= 3.98, 95% (CI): 2.10,12.89, p<0.0001). HIF-1α was associated with histological grade of cancer (Grade 3 vs. Grade 1: OR=3.77, 95% (CI): 2.76,5.16, p<0.00001; Grade 3 vs. Grade 2: OR=1.62, 95% (CI): 1.20,2.19, p=0.002; Grade 2 vs. Grade 1: OR=2.34, 95% (CI): 1.82,3.00, p<0.00001),5-years disease free survival (DFS) rates (OR=2.93, 95% (CI):1.43,6.01, p=0.001) and 5-years overall survival (OS) rates (OR=5.53, 95% (CI): 2.48,12.31, p<0.0001).

CONCLUSION

HIF-1α is associated with the malignant degree, FIGO stage, histological grade, lymph node metastasis, 5-years survival rate and recurrence rate of gynecological cancer. It may play an important role in clinical treatment and prognostic evaluation.

Association between HIF-1α C1772T/G1790A polymorphisms and cancer susceptibility: an updated systematic review and meta-analysis based on 40 case-control studies

Background

HIF-1 (hypoxia-inducible factor 1) is a transcriptional activator that functions as a critical regulator of oxygen homeostasis. Recently, a large number of epidemiological studies have investigated the relationship between HIF-1α C1772T/G1790A polymorphisms and cancer susceptibility. However, the results remain inconclusive. Therefore, we performed a meta-analysis on all of the available case-control studies to systematically summarize the possible association.

Methods

A literature search was performed using PubMed and the Web of Science database to obtain relevant published studies. Pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for the relationship between HIF-1α C1772T/G1790A polymorphisms and cancer susceptibility were calculated using fixed- and random-effects models when appropriate. Heterogeneity tests, sensitivity analyses and publication bias assessments were also performed in our meta-analysis.

Results

A total of 40 studies met the inclusion criteria were included in the meta-analysis: 40 studies comprised of 10869 cases and 14289 controls for the HIF-1α C1772T polymorphism and 30 studies comprised of 7117 cases and 10442 controls for the HIF-1α G1790A polymorphism. The results demonstrated that there were significant association between the HIF-1α C1772T polymorphism and cancer susceptibility under four genetic models (TT vs. CC: OR = 1.63, 95% CI = 1.02-2.60; CT + TT vs. CC: OR = 1.15, 95% CI = 1.01-1.34; TT vs. CT + CC: OR = 2.11, 95% CI = 1.32-3.77; T vs. C: OR = 1.21, 95% CI = 1.04-1.41). Similarly, the statistically significant association between the HIF-1α G1790A polymorphism and cancer susceptibility was found to be consistently strong in all of the genetic models. Moreover, increased cancer risk was observed when the data were stratified by cancer type, ethnicity and the source of controls.

Conclusions

This meta-analysis demonstrates that both the C1772T and G1790A polymorphisms in the HIF-1α gene likely contribute to increased cancer susceptibility, especially in the Asian population and in breast cancer, lung cancer, pancreatic cancer and oral cancer. However, further research is necessary to evaluate the relationship between these polymorphisms and cancer risk.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-950) contains supplementary material, which is available to authorized users.

Genetic polymorphisms in hypoxia-inducible factor-1a gene and its association with HBV-related hepatocellular carcinoma in a Chinese population

Previous studies have demonstrated that hypoxia-inducible factor-1a (HIF-1a) may play a vital role in the pathogenesis of hepatocellular carcinoma (HCC). However, the relationship between HIF-1a polymorphisms and HCC has not been thoroughly investigated. The aim of this study is to determine whether HIF-1a polymorphisms are associated with HCC through a case-control study. Two polymorphisms in the HIF-1a gene (rs11549465 and rs115494657) were examined in 157 hepatitis B virus (HBV)-related HCC patients and 173 healthy controls using the polymerase chain reaction-restriction fragment length polymorphism method. DNA sequencing was used to validate genotype results. There were no significant differences in the genotype and allele frequencies of HIF-1a rs11549465 and rs115494657 polymorphisms between the HBV-related HCC patients and healthy controls. However, the data revealed that subjects with the CG haplotype have a higher susceptibility to HBV-related HCC [odds ratio (OR)=2.327, 95% confidence interval (CI)=1.578-4.721, P=0.008]. In contrast, the CA haplotype was associated with a significantly decreased risk of HBV-related HCC (OR=0.416, 95% CI=0.172-0.910, P=0.025). HIF-1a rs11549465 and rs115494657 polymorphisms appeared to be irrelevant to HBV-related HCC. However, the HIF-1a CG and CA haplotypes might be a risk factor and a protective marker, respectively, for HBV-related HCC in a Chinese population. Further investigations with a larger sample size may be required to validate the genetic effects of HIF-1a polymorphisms on HBV-related HCC.

The association between hypoxia-inducible factor-1 α gene G1790A polymorphism and cancer risk: a meta-analysis of 28 case-control studies

Purpose

Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor that regulates the cellular adaptation to hypoxia. HIF-1α gene single nucleotide polymorphisms (SNPs) are implicated to be associated with cancer risks. However, results from the published studies remained inconclusive. The aim of this study is to investigate the relationship of HIF-1α gene G1790A polymorphism with cancer using meta-analysis.

Methods

A comprehensive search in Pubmed, EMBASE and China National Knowledge Infrastructure (CNKI) was conducted to identify all publications on the association between this polymorphism and cancer until December 13, 2013. Odds ratios (OR) with 95% confidence intervals (95% CI) were used to evaluate the strength of this association. Association between lymph node metastasis and G1790A was also investigated.

Results

A total of 5985 cases and 6809 controls in 28 case–control studies were included in this meta-analysis. The A allele of HIF-1α gene G1790A polymorphism was found to be significantly associated with increased cancer risk in four genetic models: AA + AG vs. GG (dominant model OR = 1.85, 95% CI = 1.27-2.69), AA vs. AG + GG (recessive model OR = 5.69, 95% CI = 3.87-8.37), AA vs. GG (homozygote comparison OR = 6.63, 95% CI = 4.49-9.79), and AG vs. GG (heterozygote comparison OR = 2.39, 95% CI = 1.53-3.75). This variant was also significantly associated with higher risks of pancreatic cancer, head and neck cancer, lung cancer and renal cell carcinoma. However, the A allele of G1790A was not significantly associated with increased lymph node metastasis in the dominant model by overall meta-analysis.

Conclusions

Our meta-analysis suggests that the substitution of G with A of HIF-1α gene G1790A polymorphism is a risk factor of cancer, especially for pancreatic cancer, lung cancer, renal cell carcinoma and head and neck cancer. The association is significant in Asian, Caucasian population and public based control subgroups. However, it’s not associated with risk of lymph node metastasis.

Hypoxia-inducible factor-1α C1772T polymorphism and cancer risk: a meta-analysis including 18,334 subjects

Studies on HIF 1α C1772T (P582S) polymorphism revealed a genetic susceptibility to malignant tumors, however, the results were conflicting. We conducted a meta-analysis utilizing 29 eligible case-control studies to analyze the data concerning the association between the HIF-1α C1772T polymorphism and cancer risks. There was statistical association between the HIF-1α CT/TT genotype and cancer risk (OR = 1.28, 95% CI = 1.06-1.54, P(heterogeneity) < .00001). The stability of these observations was confirmed by a one-way sensitivity analysis. Our findings suggested that CT/TT genotype was associated with increased risks of prostate cancer. Besides, the HIF-1α C1772T polymorphism most likely contributes to susceptibility to malignant tumors, especially in American population.

Hypoxia-inducible factor-1α (HIF-1α) C1772T polymorphism significantly contributes to the risk of malignancy from a meta-analysis

Although the association between hypoxia-inducible factor-1α (HIF-1α) C1772T polymorphism and risk of malignancy has been widely studied, results from published studies remained controversial. Therefore, the relationship between them was further assessed in this meta-analysis. The databases of PubMed, Embase, and Wanfang were searched, and odds ratio with 95% confidence interval (OR and 95% CI) were used to assess the strength of the association. A total of 38 case-control studies with 23,876 participants were included. Overall, the T allele of HIF-1α C1772T was significantly associated with increased risk of malignancy development (OR and 95% CI 1.18 (1.00-1.38), P = 0.048 for T carriers vs. CC; 1.22 (1.05-1.41), P = 0.010 for T carriers vs. C carriers). When subgroup analyses were conducted, T allele was further found to be associated with increased risk of malignancy development for Asians rather than Caucasians (OR and 95% CI 1.36 (1.10-1.67), P = 0.004 for Asians) and for population-based studies (OR and 95% CI 1.19 (1.01-1.41), P = 0.040). Between-study heterogeneity existed in genetic comparison models, and meta-regression indicated that the participants' ethnicities and types of malignancy might be the sources of heterogeneity. No publication bias was found. In conclusion, this study indicated that HIF-1α C1772T polymorphism was significantly associated with increased risk of malignancy development for Asians. More studies were further required to focus on the relationship between HIF-1α C1772T polymorphism and risk of a specific type of tumor.

The association between hypoxia-inducible factor-1 α gene C1772T polymorphism and cancer risk: a meta-analysis of 37 case-control studies

Background

The possible association between HIF-1α C1772T polymorphism and cancer risk has been studied extensively. However, the results were controversial. In order to get a more precise conclusion of this association, a meta-analysis was performed.

Methods

A total of 10186 cases and 10926 controls in 37 case-control studies were included in this meta-analysis. Allele and genotypic differences between cases and controls were evaluated. Subgroup analysis by cancer site, ethnicity, source of controls and gender was performed.

Results

The T allele of HIF-1α gene C1772T was significantly associated with increased cancer risk in three genetic models: TT+CT vs.CC (dominant model OR=1.23, 95%CI=1.03-1.47), TT vs. CT+CC (recessive model OR=2.51, 95%CI=1.54-4.09), TT vs. CC (homozygote comparison OR=2.02, 95%CI=1.21-3.39).In subgroup analysis, the frequency of the T variant was found to be significantly increased in cervical cancer, pancreatic cancer, head and neck cancer, renal cell carcinoma, Asian and female subgroups.

Conclusions

Our meta-analysis suggests that the substitution of C allele with T at HIF-1α gene C1772T polymorphism is a risk factor of cancer, especially for cervical, head and neck cancer, pancreatic cancer and renal cell carcinoma. It is also a risk factor of cancer in Asian group as well as in female group.

HIF-1α 1772 C/T and 1790 G/A polymorphisms are significantly associated with higher cancer risk: an updated meta-analysis from 34 case-control studies

Background

HIF-1 activates various genes in cancer progression and metastasis. HIF-1α 1772 C/T and 1790 G/A polymorphisms are reportedly associated with cancer risk; however, the results are inconclusive.

Methodology/Principal Findings

A meta-analysis of 34 studies that involved 7522 cases and 9847 controls for 1772 C/T and 24 studies that involved 4884 cases and 8154 controls for 1790 G/A was conducted to identify the association of C/T and G/A polymorphisms with cancer risk. Odds ratio (OR) and 95% confidence intervals (95% CI) were used to assess the strength of association.

HIF-1α 1772 C/T and 1790 G/A polymorphisms were associated with higher cancer risk in homozygote comparison (1772C/T: TT vs. CC: OR = 2.45, 95% CI: 1.52, 3.96; P_{heterogeneity} = 0.028; 1790G/A: AA vs. GG: OR=4.74, 95% CI: 1.78, 12.6; P_{heterogeneity} < 0.01), dominant model (1772C/T: TT/CT vs. CC: OR = 1.27, 95% CI: 1.04, 1.55; P_{heterogeneity} < 0.01, 1790G/A: AA/GA vs. GG: OR = 1.65, 95% CI: 1.05, 2.60; P_{heterogeneity} < 0.01), T allele versus C allele (T vs. C: OR = 1.42, 95% CI: 1.18, 1.70; P_{heterogeneity} < 0.01), and A allele versus G allele (A vs. G: OR = 1.83, 95% CI: 1.13, 2.96; P_{heterogeneity} < 0.01). On a subgroup analysis, the 1772 C/T polymorphism was significantly linked to higher risks for breast cancer, lung cancer, prostate cancer, and cervical cancer, whereas the 1790 G/A polymorphism was significantly linked to higher risks for lung cancer and prostate cancer. A significantly increased cancer risk was found in both Asians and Caucasians for 1772C/T polymorphism, whereas a significantly increased cancer risk was found in Caucasians in the heterozygote comparison and recessive model for 1790G/A polymorphism.

Conclusions

HIF-1α 1772 C/T and 1790 G/A polymorphisms are significantly associated with higher cancer risk.

The association between HIF-1α polymorphism and cancer risk: a systematic review and meta-analysis

Epidemiological studies have assessed the association between HIF-1α polymorphisms and cancer risk. However, the results remained conflicting rather than conclusive. Therefore, we performed a systematic review to provide a complete picture and conducted a meta-analysis to derive a precise estimation. We searched PubMed, Embase, and China National Knowledge Infrastructure (CNKI) databases until July 2013 to identify eligible studies. Data sets (43) from 39 studies with a total of 10,841 cases and 14,682 controls were included. The most commonly investigated polymorphism was C1772T, followed by G1790A, C111A, and rs2057482. Overall, C1772T and G1790A but not rs2057482 were associated with increased risk for cancer. When stratified by cancer type, C1772T was associated with increased risk for cervical cancer (T/T vs. C/T+C/C: OR = 8.80, 95 % CI = 2.30-33.70), prostate cancer (T vs. C: OR = 1.54, 95 % CI = 1.04-2.30), and other cancers (T vs. C: OR = 1.42, 95 % CI = 1.07-1.89), but not oral, breast, colorectal, endometrial, lung, and bladder cancers or renal cell carcinoma. G1790A was associated with marginal but insignificant risk for prostate cancer (A vs. G: OR = 1.46, 95 % CI = 1.00-2.13, P = 0.056) and with increased risk for oral (A vs. G: OR = 9.66, 95 % CI = 1.31-71.15), lung (A vs. G: OR = 2.27, 95 % CI = 1.74-2.96), and other cancers (A vs. G: OR = 2.06, 95 % CI = 1.26-3.37) and renal cell carcinoma (A/A vs. G/A+G/G: OR = 3.05, 95 % CI = 1.36-6.84), but not breast, colorectal, cervical, or bladder cancer. Furthermore, we detected increased cancer risk in haplotypes TA and CA and in those carrying at least one risk allele, and decreased cancer risk in haplotype TG regarding C1772T and G1790A polymorphisms. Further well-designed studies on various cancer types are warranted to verify our findings.

Clinicopathological significance of hypoxia-inducible factor-1 alpha polymorphisms in cancers: evidence from a meta-analysis

The associations between hypoxia-inducible factor-1 alpha (HIF-1α) and clinicopathological characteristics of cancers have been evaluated in various studies, with the conflicting results. Therefore, we conducted a meta-analysis by combining available data to derive a more precise estimation of the association. PubMed, Embase, and China National Knowledge Infrastructure (CNKI) were searched until February 2013 to identify eligible studies. A total of 25 studies were included, with all studies investigating the role of HIF-1α C1772T polymorphism in clinicopathological parameters in cancers while 17 of them investigating HIF-1α G1790A polymorphism only. Results suggested that HIF-1α C1772T polymorphism was associated with histological grade of cancer (T/T + C/T vs. C/C, grade 3 vs. grade 2: OR = 1.51, 95% CI = 1.08-2.13; grade 2 vs. grade 1: OR = 0.67, 95% CI = 0.46-0.97) and increased risk of lymph node metastasis (T/T + C/T vs. C/C: OR = 1.38, 95% CI = 1.13-1.68). HIF-1α G1790A polymorphism was found to be associated with increased risk of larger tumor size (G/G + G/A vs. A/A: OR = 1.64, 95% CI = 1.04-2.58) and borderline significant risk of lymph node metastasis (G/G + G/A vs. A/A: OR = 1.33, 95% CI = 1.00-1.78). Therefore, HIF-1α polymorphisms could be a potential prognostic factor for cancer. Further studies with larger data set and well-designed models are required to validate our findings.

1790 G/A polymorphism, but not 1772 C/T polymorphism, is significantly associated with cancers: an update study

This study aimed to investigate the association between PASD8 gene and cancers. For 1772 C/T polymorphism (rs11549465), it included 5552 cases and 8044 controls, and for 1790 G/A (rs11549467), 3381 cases and 5830 controls. The allele-analysis results showed that 1772 C/T (rs11549465) was significantly associated with cancers (OR: 1.177, 95% CI: 1.011-1.369, p=0.035). And results of genotype-analysis indicated that 1790 G/A (rs11549467) had a significant relationship with cancers. (OR: 0.736, 95% CI: 0.595-0.910, p=0.005). For 1790 G/A (rs11549467), the association was significant when subdivided by different kinds of cancers. And no association existed when subdivided into population-type subgroups. In conclusion, PASD8 gene played an important role in the development of cancers.

Clinical applications of levonorgestrel-releasing intrauterine system to gynecologic diseases

The levonorgestrel-releasing intrauterine system (LNG-IUS), originally designed for contraception, has since been applied to various gynecologic diseases. This article summarizes the current status of clinical applications of LNG-IUS to the treatment of gynecologic diseases such as heavy menstrual bleeding, endometriosis, leiomyoma, adenomyosis, endometrial hyperplasia, and early-stage endometrial cancer.

Association of hypoxia inducible factor-1α polymorphisms with susceptibility to non-small-cell lung cancer

Hypoxia-inducible factor-1α (HIF-1α) is a key regulator of cellular response to hypoxia and has been suggested to play an important role in tumorigenesis and metastasis. The aim of this study was to investigate the role of HIF-1α-1772 C/T (P582S) and -1790 G/A (A588T) polymorphisms in the susceptibility to and severity of non-small-cell lung cancer (NSCLC). Using a case-control study design and polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis, the allele frequencies and genotype distributions of each single nucleotide polymorphism in 285 NSCLC cases and 300 gender-matched controls were compared. The distribution of the genotype frequencies of HIF-1α-1772 C/T and -1790 G/A were significantly different between the NSCLC and the controls. Logistic regression analysis revealed that higher odds ratios (ORs) for lung cancer were observed for individuals with HIF-1α-1772 T/T genotype against CC/CT genotypes (an OR of 4.04, 95% confidence interval [CI] = 2.02-8.08, P = 0.0001), and HIF-1α-1790 A/A genotype against GG/GA genotypes (an OR of 4.42, 95% CI 2.22-8.78, P < 0.0001). There were no relationship between HIF-1α-1772 C/T or -1790 G/A allele distribution and disease severity of NSCLC (P > 0.05). However, those patients carrying a HIF-1α-1772 T/T genotype or a HIF-1α-1790 A/A had a tendency toward inferior prognosis compared with other patients.

Genetic polymorphisms as predictive and prognostic biomarkers in gynecological cancers: a systematic review

PURPOSE

Numerous studies have explored the potential role of genetic polymorphisms as predictive or prognostic biomarkers in gynecologic malignancies. A systematic review for all eligible polymorphisms has not yet been reported. The aim of this study was to summarize the current status of the field and provide direction for future research.

DESIGN

We searched literature databases (MEDLINE, EMBASE, Cochrane) from 2006 to April 2011 to identify studies evaluating the association between gene polymorphisms and clinical outcome in ovarian, endometrial, cervical, or vulvar cancer. The main outcome measures were overall survival (OS) and progression-free survival (PFS). Studies reporting relationships between polymorphisms and toxicity were also included.

RESULTS

Sixty two studies met the inclusion criteria. The median sample size was 140. Most of the included studies (n=50, 81%) were conducted in ovarian cancer patients. Almost a third assessed potential predictive associations between gene polymorphism and outcome in ovarian cancer. The most commonly evaluated genes were ERCC1, VEGF, ABCB1 (MDR), and GSTP1. Most studies (n=44, 71%) were observational case-series. Only four studies (6%) included a validation arm and patient population ethnicity was explicitly stated only in 27% of included studies.

CONCLUSION

No consistent association between any gene polymorphism and clinical outcome in gynecological cancers has been found across studies. There is incomplete adherence to the REMARK guidelines and inadequate methodology reporting in most studies. Moving forward, analysis of large trial-based clinical samples; adherence to the highest methodological standards, and focus on validation analyses are necessary to identify clinically useful pharmacogenomic biomarkers of outcome.