Heterozygous genetic variations of FOXP3 in Xp11.23 elevate breast cancer risk in Chinese population via skewed X-chromosome inactivation

The association of FOXP3 gene polymorphisms with cancer susceptibility: a comprehensive systemic review and meta-analysis

The role of forkhead box P3 (FOXP3) protein in tumorigenesis has long been controversial and existing data on the association between FOXP3 gene polymorphisms and cancer susceptibility were inconsistent. Here, we conducted a meta-analysis to better clarify the relationship. A comprehensive search of studies published from July 2008 to June 2018 was conducted. The statistical analyses of the pooled odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs) were performed using the Revman 5.2 software. A total of 12 articles with 19 case–control studies and 10389 participants were included. Three FOXP3 polymorphisms and six cancer types were evaluated. While no significant results were observed in overall and breast cancer groups for rs3761548 (A/C) polymorphisms, the pooled data showed an elevated risk of cancer in variant AA genotypes and A allele for Chinese population (AA vs. AC+CC: OR = 1.61, 95% CI = 1.09, 2.39; AA vs. CC: OR = 1.74, 95% CI = 1.05, 2.89; A vs. C: OR = 1.34, 95% CI = 1.00, 1.78). Neither the overall group analyses nor the subgroup analyses stratified by cancer type and ethnicity proposed any significant association of rs2280883 (C/T) and rs3761549 (T/C) polymorphisms with cancer susceptibility. This meta-analysis suggested that FOXP3 rs3761548 (A/C) polymorphisms were associated with increased cancer risk in Chinese population while rs2280883 (C/T) and rs3761549 (T/C) polymorphisms were not. More large-sample researches with diverse ethnicities and cancer types are needed to draw a concrete conclusion.

Association of Crohn's disease with Foxp3 gene polymorphisms and its colonic expression in Chinese patients

Background

Fork head/winged helix transcription factor (Foxp3) plays a pivotal role in regulatory T (Treg) cells. The present study aimed to assess the association of Crohn's disease (CD) with Foxp3 polymorphisms and its colonic expression in Chinese patients.

Methods

The Foxp3 polymorphisms, rs3761547, rs2232365, rs2294021, and rs3761548, were examined by SNaPshot in 268 CD patients and 490 controls. The colonic expression levels of Foxp3, IL‐2, and IL‐4 were detected in 31 CD patients and 31 controls using real‐time quantitative polymerase chain reaction, immunohistochemistry, and enzyme‐linked immunosorbent assay.

Results

Compared to male controls, the proportion of variant allele of rs3761547 was increased in male patients. The variant alleles of rs3761547, rs2232365, and rs2294021 were less in male patients with stricturing CD compared to those with non‐stricturing, non‐penetrating CD; however, these variants were frequently detected in male patients with colonic CD than in those with ileocolonic CD. The variant allele of rs3761548 was increased in male patients with penetrating CD compared to those with non‐stricturing, non‐penetrating CD. The colonic expression of Foxp3 was higher in CD patients than in controls (both males and females). Compared to male patients carrying wild‐type alleles, the colonic expression of Foxp3 was downregulated in male patients with variant alleles, rs3761547, rs2232365, rs2294021, and rs3761548, respectively. However, the Foxp3 polymorphisms were not significantly related with the colonic expression levels of IL‐2 and IL‐4 in CD patients (both males and females).

Conclusion

Foxp3 polymorphisms might increase the CD susceptibility by reducing the colonic expression of Foxp3 in male patients.

Association of two FOXP3 polymorphisms with breast cancer susceptibility in Chinese Han women

Background

Forkhead box P3 (FOXP3) is a key gene in the immune system which also plays a role in tumor development. This study aims to explore the association of two FOXP3 polymorphisms (rs3761548 and rs3761549) with susceptibility to breast cancer (BC).

Method

A case–control study was conducted, involving 560 patients and 583 healthy individuals from the Chinese Han population. The genotypes of FOXP3 polymorphisms were detected using the Sequenom MassARRAY method. The association between FOXP3 polymorphisms and BC risk was evaluated using a χ² test with an odds ratio (OR) and 95% confidence intervals (95% CIs) under six genetic models. False-positive report probability was utilized to examine whether the significant findings were noteworthy.

Results

We observed that rs3761548 was associated with a higher BC risk in heterozygous, dominant, overdominant, and allele genetic models (CA vs CC: OR =1.32, P=0.031; CA/AA vs CC: OR =1.32, P=0.023; CA vs CC/AA: OR =1.29, P=0.042; A vs C: OR =1.26, P=0.029), whereas no significant association was found between rs3761549 and BC risk. In addition, CA, CA/AA genotype, and A allele of rs3761548 were related to larger tumor size, and the A allele was also correlated with a positive status of Her-2 in BC patients.

Conclusion

Our study suggests that FOXP3 polymorphism rs3761548 is associated with BC susceptibility in the Chinese and may be involved in tumor progression. Future studies are needed to confirm the results in a larger population with more races.

FOXP3 Allelic Variants and Haplotype Structures Are Associated with Aggressive Breast Cancer Subtypes

FOXP3 genetic polymorphisms have been associated with cancer development and prognosis. In this context, the present study aimed to evaluate the g.10403A>G (rs2232365) polymorphisms and g.8048A>C (rs3761548), in aggressive breast cancer (BC) subtypes, including, Luminal B HER2+ (LB), HER2-enriched (HER2+), and triple-negative (TN). Polymerase chain reaction followed by enzymatic restriction was performed to genotyping 117 BC samples and 300 controls. A significant association of AA genotype (g.10403A>G) in relation to BC susceptibility (OR = 1.93; 95% CI = 1.01–3.66; p = 0.046) was observed. The GG (g.10403A>G) genotype was correlated with higher proliferation index (Ki-67) in HER2+ subtype (τ = 0.47; p = 0.019) and advanced TNM staging in TN (τ = 0.23; p = 0.032). A correlation of AA genotype (g.8048A>C) with higher Ki-67 (τ = −0.47; p = 0.018) and lower histological grade (τ = 0.39; p = 0.026) in HER2+ was also found. GA haplotype was correlated with lower histological grade (τ = −0.15; p = 0.009) and higher Ki-67 (τ = 0.43; p = 0.036) in HER2+ and advanced staging in TN (τ = 0.29; p = 0.044). On the other hand, AC haplotype was correlated with lower Ki-67 (τ = −0.54; p = 0.005) and staging (τ = −0.29; p = 0.027) in HER2+ and TN respectively. Results showed that FOXP3 influence regarding clinical outcome depends greatly on the BC subtype and indicated this transcription factor as a promising marker in aggressive BC subtypes.

Copy number variants and genetic polymorphisms in TBX21, GATA3, Rorc, Foxp3 and susceptibility to Behcet's disease and Vogt-Koyanagi-Harada syndrome

This study aimed to investigate the role of genetic variants including single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) of TBX21, GATA3, Rorc and Foxp3 genes in Behcet's disease (BD) and Vogt-Koyanagi-Harada (VKH) syndrome in a Chinese Han population. Genotyping of 25 SNPs was performed by iPLEX system (Sequenom) or polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). TaqMan real time PCR was used to assess CNVs. The expression of Rorc and Foxp3 were examined by real-time PCR and cytokine production was measured by ELISA. High Rorc CNV was associated with the susceptibility to BD (P = 8.99 × 10(-8), OR = 3.0), and low Foxp3 CNV predisposed to BD in female patients (P = 1.92 × 10(-5), OR = 3.1). CNVs for the investigated genes were not altered in VKH syndrome. Further functional studies demonstrated that the relative mRNA expression levels of Rorc were increased in individuals with high Rorc copy number, but not for Foxp3. Increased production of IL-1β and IL-6 was found in individuals carrying a high CNV of Rorc. Our study showed that high CNVs of Rorc and low CNVs of Foxp3 confer risk for BD but not for VKH syndrome. The tested 25 SNPs in TBX21, GATA3, Rorc and Foxp3 did not associate with BD and VKH syndrome.

The relationship between skewed X chromosome inactivation and the prognosis of Graves' and Hashimoto's diseases

BACKGROUND

Autoimmune thyroid diseases (AITDs) predominantly develop in females. One of two X chromosomes is randomly inactivated by methylation in each female cell, but it has been reported that skewed X chromosome inactivation (XCI) may be associated with the development of autoimmune diseases. To clarify the significance of skewed XCI in the prognosis and development of AITD, we investigated the proportion of skewed XCI in female patients with AITD.

METHODS

We analyzed the degree of XCI skewing in 120 female patients with AITD (77 patients with Graves' disease [GD] and 43 patients with Hashimoto's disease [HD]) and 49 female controls in DNA from peripheral blood mononuclear cells (PBMC). We performed XCI analysis by digesting inactive DNA with a methylation-sensitive restriction enzyme (HpaII) followed by a polymerase chain reaction (PCR) assay for the polymorphic CAG repeat of the androgen receptor gene and electrophoresis of the PCR products.

RESULTS

The proportion of skewed XCI (≥65% skewing) was not significantly different between AITD patients and control subjects but was higher in patients with intractable GD (66.7%) than those with GD in remission (25.0%, p=0.0033) and control subjects (32.6%, p=0.0038). When the cutoff value for XCI skewing was relaxed, the proportion of skewed XCI (≥60% skewing) was higher in patients with severe HD (76.5%) than in those with mild HD (41.2%, p=0.0342).

CONCLUSIONS

Skewed XCI is related to the prognosis of AITD, particularly the intractability of GD.

Association between FOXP3 promoter polymorphisms and cancer risk: A meta-analysis

Epidemiological studies have been conducted to investigate the association between the FOXP3 promoter polymorphisms, rs3761549 and rs3761548, and the risk of cancer. However, the results from these studies have been controversial. In order to obtain a more precise conclusion of this association, the present meta-analysis was performed. The odds ratio (OR) and 95% confidence interval (95% CI) values were used to assess any correlations between the data. Overall, the rs3761549 (C>T) and rs3761548 (C>A) polymorphisms of the FOXP3 gene were not associated with the cancer risk in an Asian population. In the subgroup analyses based on cancer type, no significant associations were identified between these two polymorphisms and breast cancer. However, the results altered when the analyses were restricted to hepatocellular carcinoma (HCC) and non-small cell lung cancer (NSCLC) (for rs3761549: TT+CT vs. CC OR, 0.52, 95% CI, 0.38-0.72; TC vs. CC OR, 0.25, 95% CI, 0.16-0.39; T vs. C OR, 0.76, 95% CI, 0.59-0.97. For rs3761548: AA vs. AC+CC OR, 3.20, 95% CI 1.76-5.81; AA+AC vs. CC OR, 2.56, 95% CI, 1.75-3.76; AA vs. CC OR, 4.41, 95% CI, 2.36-8.25; AC vs. CC OR, 2.15, 95% CI, 1.42-3.25; A vs. C OR, 2.32, 95% CI, 1.74-3.10). The present meta-analysis indicates that the FOXP3 rs3761549 (C>T) and rs3761548 (C>A) polymorphisms are not associated with the risk of breast cancer, but with the risk of HCC and NSCLC. Therefore, a study with a larger sample size is required to further evaluate this association.

Functional polymorphisms in interleukin-23 receptor and susceptibility to esophageal squamous cell carcinoma in Chinese population

BACKGROUND

As a key element in the T-helper 17 (Th17) cell-mediated inflammatory process, interleukin-23 receptor (IL-23R) plays a crucial role in the pathogenesis of cancer. Single nucleotide polymorphisms (SNPs) in IL-23R have been frequently studied in several previous case-control cancer studies, but its association with esophageal squamous cell carcinoma (ESCC) in Chinese population has not been investigated. This study examined whether genetic polymorphisms in IL-23R were associated with ESCC susceptibility.

METHODS

A hospital-based case-control study of 684 ESCC patients and 1064 healthy controls was performed to assess the association between four previous reported IL-23R genotypes (rs6682925, rs6683039, rs1884444 and rs10889677) and ESCC risk. The results revealed that the C allele of the rs10889677A>C polymorphism in the 3'UTR of IL-23R gene was inversely associated with the risk of ESCC.

RESULTS

The rs10889677AC genotype had significantly decreased cancer risk (odds ratio [OR]  = 0.85, 95% confidence interval [CI]  = 0.69-1.01) compared to subjects homozygous carriers of rs10889677AA, the risk decreased even further in those carrying rs10889677CC genotype (OR = 0.64, 95% CI = 0.44-0.93). No significant association was found between the other three polymorphisms and the risk of ESCC.

CONCLUSION

These findings indicated that rs10889677A>C polymorphism in IL-23R may play a protective role in mediating the risk of ESCC.

Foxp3 promoter polymorphism (rs3761548) in breast cancer progression: a study from India

Breast cancer is the most common female neoplasm that drives the transformation of normal mammary epithelial cells into highly malignant derivatives. Forkhead Box Protein3 (Foxp3), a tumor suppressor/immunomodulatory gene, which controls the function of Treg cells and oncogenes is down regulated in breast cancer. The main aim of the present study is to evaluate the potential influence of Foxp3-3279 C>A polymorphism (rs3761548) and -2383 C>T polymorphism (rs3761549) in 202 breast cancer patients and 130 normal healthy women of Indian origin. The genotypes were determined using ARMS-PCR for rs3761548 and PCR-RFLP method for rs3761549 using specific primers. The results revealed lack of association of these two polymorphisms with breast cancer susceptibility. However, with respect to AA genotype of rs3761548, we found highly significant association with the advanced stage (T3-4) of the tumor (OR = 3.90; 95% confidence interval (CI) = 1.56-9.70; p = 0.03). Stratified data also revealed an association of homozygous mutant genotype with advanced stage of tumor in premenopausal women (OR = 4.56; 95% CI = 1.07-19.38; p = 0.04) with disease duration of <6 months (OR =  .10; 95% CI = 1.80-20.50; p = 0.002) suggestive of modulating effect of rs3761548 in tumor progression. We conclude that Foxp3 rs37161548 has a potential to be a polymorphic marker for tumor progression in premenopausal breast cancer patients in Indian women.

High frequency of the X-chromosome inactivation in young female patients with high-grade glioma

BACKGROUND

Gliomas are common tumors and high-grade ones account for 62% of primary malignant brain tumors. Though current evidence have suggested that inherited risks play a role in glioma susceptibility, it was conveyed that glioma was such a complex disease, and the direct genetic contribution to glioma risk factors and its relation to other factors should be discussed more deeply. X-chromosome inactivation (XCI) is the mechanism by which gene dosage equivalence is achieved between female mammals with two X chromosomes and male mammals with a single X chromosome. As skewed XCI has been linked to development of some solid tumors, including ovarian, breast, and pulmonary and esophageal carcinomas, it is challenging to elucidate the relation of skewed XCI to high-grade gliomas development.

OBJECTIVE

The present study aimed to determine the general concordance between XCI pattern in blood cells and brain tissues, and SXCI frequencies in female patients with high-grade glioma compared to healthy controls.

METHODS

1,103 Chinese females without a detectable tumor and 173 female high-grade glioma patients, were detected in the study. Normal brain tissues surrounding the lesions in gliomas were obtained from 49 patients among the 173 ones, with the microdissection using a laser microdissection microscope Genomic DNA was extracted from the peripheral blood cells and the normal brain tissues from the subjects. Exon 1 of androgen receptor (AR) gene was amplified, and its products of different alleles were resolved on denaturing polyacrylamide gels and visualized after silver staining. The corrected ratios (CR) of the products before and after HpaII digestion were calculated.

RESULTS

Occurrence of SXCI was detected in both the patients and controls at similar frequencies. However, the phenomenon, as defined as CR ≥ 3, was more frequent in the patients aging ≤ 40 (23.6%) compared to the corresponding reference group (5.1%, P <0.0001). When CR ≥ 10 was adopted, the frequencies were 5.5% and 1.6%, respectively. Their difference did not attain statistical significance (P=0.10). When detected, both blood cells and brain tissue were compared after determination of a high concordance of XCI between blood cells and brain tissue collected from the same individuals (n=48, r =0.57, P <0.01).

CONCLUSIONS

The data from the current study demonstrated that SXCI may be a predisposing factor for development of high-grade glioma in young female patients and further study will verify its suitability as a biomarker to assess susceptibility of young female patients to high-grade glioma.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1935066233982578.

IPEX Syndrome, FOXP3 and Cancer

In this review, we introduce the IPEX syndrome and its relationship with germline mutations of the FOXP3 gene. We then describe the multiple functional roles of FOXP3 in regulatory T cells and epithelial cells as well as in IPEX syndrome and tumor progression. Potential mechanisms of FOXP3 inactivation and transcriptional regulation are discussed with recent advances. Finally, we point out current issues and a potential FOXP3-mediated therapeutic strategy as well as the reactivation of FOXP3 in patients with IPEX syndrome and cancer.

Skewed X-chromosome inactivation in patients with esophageal carcinoma

Abstract

Skewed X-chromosome inactivation (SXCI) was found in some apparently healthy females mainly from Western countries. It has been linked to development of ovarian, breast and pulmonary carcinomas. The present study aimed to observe the SXCI frequencies in apparently healthy Chinese females and patients with esophageal carcinoma. DNA was extracted from the peripheral blood cells from 401 Chinese females without a detectable tumor and 143 female patients with esophageal carcinoma. Exon 1 of androgen receptor (AR) gene was amplified, and the products of different CAG alleles were resolved on denaturing polyacrylamide gels and visualized after silver staining. The corrected ratios (CR) of the products before and after HpaII digestion were calculated. As to the healthy females, when CR ≥ 3 was used as a criterion, SXCI was found in two (4.3%) of the 46 neonates, 13 (7.8%) of the 166 younger adults (16–50 years) and 37 (25.7%) of the 144 elderly females (51–96 years), with the frequency higher in the elderly subjects than in the two former groups (P < 0.05). When a more stringent criterion (CR ≥ 10) was used, SXCI was found in one (2.2%), two (1.2%) and 16 (11.1%) of the subjects in the three age groups, respectively, itsfrequency being higher in the elderly than in the younger age groups (P < 0.05). Occurrence of SXCI was detected in both the patients and controls at similar frequencies. However, the phenomenon, as defined as CR ≥ 3, was more frequent in the patients aging <40 years (35.7%) compared to the corresponding reference group (7.6%, P = 0.006). When CR ≥ 10 was adopted, the frequencies were 7.1% and 1.2%, respectively. Their difference did not attain statistical significance (P = 0. 217). SXCI also occurs in apparently healthy Chinese females, and is associated with age. It may be considered as a predisposing factor for the early development of esophageal carcinoma.

Virtual slides

The virtual slide(s) for this article can be found here http://www.diagnosticpathology.diagnomx.eu/vs/1542364337927656