Sex- and Age-Related Estrogen Signaling Alteration in Inflammatory Bowel Diseases: Modulatory Role of Estrogen Receptors.

The pathogenesis of inflammatory bowel diseases (IBD) seems to be associated with alterations of immunoregulation. Several lines of evidence suggest that estrogens play a role in the modulation of immune responses and may be related to the etiology of IBD. The purpose of this work was to examine the involvement of G protein-coupled estrogen receptor (GPER), estrogen receptor α (ERα), estrogen receptor ß (ERß) and ERα spliced variants ERα36 and ERα46 in Crohn's disease (CD) and ulcerative colitis (UC). The studied group included 73 patients with IBD and 31 sex and age-related controls. No differences in serum levels of 17ß-estradiol nor of CYP1A1 and SULT1E1 enzymes involved in estrogen catabolism were stated. The expression pattern of estrogen receptors in tissue samples was quantified using real-time PCR and Western blotting. Statistically significant up-regulation of GPER and ERα in both CD and UC as well as down-regulation of ERß in CD patients was found. However, differences in the expression of estrogen receptors in CD and UC have been identified, depending on the sex and age of patients. In men, up-regulation of GPER, ERα and ERα46 expression was shown in CD and UC patients. In women under 50 years of age, GPER protein level increased in UC whereas ERß expression tended to decrease in CD and UC patients. In turn, in women over 50 the protein level of ERα increased in UC while ERß expression decreased in CD patients. Dysregulation of estrogen receptors in the intestinal mucosa of patients with CD and UC indicates that estrogen signaling may play a role in the local immune response and maintain epithelial homeostasis in a gender- and age-dependent manner.

G protein-coupled receptor 55 (GPR55) expresses differently in patients with Crohn's disease and ulcerative colitis.

AIM: To investigate the levels of G protein-coupled receptor 55 (GPR55) expression in colonic tissue of inflammatory bowel disease (IBD) patients and healthy controls, and its potential implication in IBD treatment. METHODS: Fifty patients were enrolled in our prospective study: n = 21 with Crohn's disease (CD) and n = 16 with ulcerative colitis (UC); 19 women and 18 men. Control consisted of 13 non-IBD patients. In each subject, two biopsies were taken from different colonic locations. In IBD patients, biopsies both from endoscopically inflamed and non-inflamed areas were drawn and the development of inflammation confirmed in histopathological examination. GPR55 mRNA and protein expression were measured using real-time PCR and Western blot, respectively. RESULTS: GPR55 expression at mRNA and protein level was detected in all samples tested. The level of GPR55 mRNA expression in non-inflamed colonic areas was comparable in all analyzed groups (p = .2438). However, in the inflamed tissues GPR55 mRNA expression was statistically significantly (p < .0001) higher (6.9 fold) in CD patients compared to UC. Moreover, CD patients manifested higher (12.5 fold) GPR55 mRNA expression in inflamed compared with non-inflamed colonic tissues (p < .0001). Although no significant differences were stated, GPR55 protein level tends to decrease in IBD as compared to control. CONCLUSIONS: Different patterns of GPR55 expression at mRNA level were observed in IBD patients. We speculate that GPR55 is crucial for the mucosal inflammatory processes in IBD, particularly in CD and its expression may affect disease severity, and response to treatment. The GPR55 receptors may become an attractive target for novel therapeutic strategies in IBD.

[GPER receptor - the new player in estrogen signaling]. / Receptor GPER - nowy gracz w sygnalizacji estrogenowej.

Recent studies reveal that estrogens act on cells and tissues, not only through two canonical estrogen receptors ERα and ERß, but also through the receptor coupled with G proteins, named GPER, formerly GPR30, and member of seven transmembrane receptor superfamily. GPER was found to be implicated both in rapid non-genomic estrogen response and in transcriptional regulation. Effects of GPER include activation of MAPK and PI3K signaling pathways, stimulation of adenyl cyclase, and mobilization of calcium ions from intracellular stores, as well as upregulation of genes such as FOS and CTGF. Identification of agonists and antagonists of GPER allowed not only to shed light on the participation of estrogen signaling in the biology and pathobiology of hormone-dependent tissues, but also its importance in the estrogen and antiestrogen therapies. Antiestrogens tamoxifen, raloxifene, or fulvestrant proved,to be agonists of GPER, which undoubtedly is not without significance for the efficacy of the therapy.

Anti-inflammatory and antinociceptive action of an orally available nociceptin receptor agonist SCH 221510 in a mouse model of inflammatory bowel diseases.

The nociceptin receptors (NOPs) are expressed in the gastrointestinal (GI) tract on muscle cell membranes and neurons, as well as the immune cells that infiltrate the mucosa. The involvement of NOPs in the pathophysiology of GI inflammation has been suggested, but due to the lack of selective NOP agonists, it never fully elucidated. Our aim was to characterize the anti-inflammatory and antinociceptive effect of the NOP agonist, SCH 221510 [3-endo-8-[bis(2-methylphenyl)methyl]-3-phenyl-8-azabicyclo [3.2.1]octan-3-ol], as a potential therapeutic strategy in the treatment of inflammatory bowel diseases (IBD). The anti-inflammatory action of SCH 221510 was determined after intraperitoneal, oral, and intracolonic administration of SCH 221510 (0.1-3.0 mg/kg once or twice daily) in mice treated with 2,4,6-trinitrobenzenesulfonic acid (TNBS). Antinociceptive action of SCH 221510 was evaluated in the mouse model of mustard oil (MO)-induced abdominal pain. Relative NOP mRNA expression was assessed in patients with IBD using real-time reverse transcriptase-polymerase chain reaction. We found that the expression of NOP mRNA was significantly decreased in patients with IBD. The administration (0.1 and 1.0 mg/kg i.p. twice daily and 3 mg/kg p.o. twice daily) of SCH 221510 attenuated TNBS colitis in mice. This effect was blocked by a selective NOP antagonist [J-113397 [(±)-1-[(3R*,4R*)-1-(cyclooctylmethyl)-3-(hydroxymethyl)-4-piperidinyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one]]. The intracolonic injections of SCH 221510 did not improve colitis in mice. The antinociceptive effect of SCH 221510 was observed after oral administration of SCH 221510 in MO-induced pain tests in mice with acute colitis. In conclusion, our results show a potent anti-inflammatory and antinociceptive effect upon selective activation of NOP receptors and suggest that the NOP agonist SCH 221510 is a promising drug candidate for future treatment of IBD.

Molecular basis of taste sense: involvement of GPCR receptors.

Taste perception is one of the senses crucial for many organisms. There are five basic tastes, i.e., sweet, bitter, salty, sour, and umami, and it is suggested that the taste of fat should be included in this list. This paper reviews the current state of knowledge about the involvement of G protein coupled receptors (GPCRs) in taste sensing and intracellular signaling. GPCR receptors are focal point of interest for pharmaceutical industry. However, their ability to interact with a variety of taste substances makes these receptors interesting target for food and nutrient companies.

A multi-faceted analysis of RutD reveals a novel family of α/ß hydrolases.

The rut pathway of pyrimidine catabolism is a novel pathway that allows pyrimidine bases to serve as the sole nitrogen source in suboptimal temperatures. The rut operon in E. coli evaded detection until 2006, yet consists of seven proteins named RutA, RutB, etc. through RutG. The operon is comprised of a pyrimidine transporter and six enzymes that cleave and further process the uracil ring. Herein, we report the structure of RutD, a member of the α/ß hydrolase superfamily, which is proposed to enhance the rate of hydrolysis of aminoacrylate, a toxic side product of uracil degradation, to malonic semialdehyde. Although this reaction will occur spontaneously in water, the toxicity of aminoacrylate necessitates catalysis by RutD for efficient growth with uracil as a nitrogen source. RutD has a novel and conserved arrangement of residues corresponding to the α/ß hydrolase active site, where the nucleophile's spatial position occupied by Ser, Cys, or Asp of the canonical catalytic triad is replaced by histidine. We have used a combination of crystallographic structure determination, modeling and bioinformatics, to propose a novel mechanism for this enzyme. This approach also revealed that RutD represents a previously undescribed family within the α/ß hydrolases. We compare and contrast RutD with PcaD, which is the closest structural homolog to RutD. PcaD is a 3-oxoadipate-enol-lactonase with a classic arrangement of residues in the active site. We have modeled a substrate in the PcaD active site and proposed a reaction mechanism.

Dysregulation of betaglycan expression in primary human endometrial carcinomas.

TGFß signaling cascade plays a vital role in neoplastic transformation, but the function of betaglycan, which is a TGFß accessory receptor, is still unknown in particular cancer. Evaluation of betaglycan expression both at mRNA (real-time PCR) and protein (ELISA) level in the context of TGFß canonical signaling components, i.e., TGFß1, TGFß2, and TGFßRII, in endometrial carcinomas was performed. Betaglycan mRNA expression level was significantly (p < .001) downregulated with simultaneous betaglycan protein level upregulation in cancer samples. Obtained results suggest that endometrial cancer is associated with disruption of accessory receptor betaglycan expression, what may alter TGFß2-induced signaling.

Expression of endoglin in primary endometrial cancer.

OBJECTIVE: Alterations in the transforming growth factor-ß (TGF-ß) signaling cascade are engaged in the development of human neoplasms through the deregulation of proliferation, differentiation and migration. However, in endometrial cancer, the role of endoglin, which acts as an accessory receptor in the TGF-ß pathway, is still unknown. The aim of our study was the evaluation of endoglin mRNA and protein expression levels in endometrial cancer as compared to normal endometrium. TGF-ß(1) and TGF-ß type II receptor were involved in the investigation since they directly cooperate with endoglin during signal propagation. Obtained results were correlated with clinicopathological parameters of studied material to determine endoglin contribution to tumor development and progression. METHODS: mRNA level assessment was performed using real-time technique, whereas protein expression was determined by ELISA assay. RESULTS: The endoglin mRNA level was not significantly altered in cancerous samples as compared to normal tissue, whereas its protein level demonstrated significant upregulation (p < 0.001) associated with increased tumor malignancy, assessed by histological grade and myometrium infiltration. CONCLUSIONS: An increase in endoglin protein expression level may interfere with the oncogenic potential of TGF-ß(1) and TGF-ß type II receptor in endometrial cancer. Correlation of the endoglin level with pronounced cancer malignancy suggests that it may be regarded as a potential prognostic marker of primary endometrial cancer.

Concentration of cadmium, nickel and aluminium in female breast cancer.

AIMS: The aim of this study was to investigate the cadmium (Cd), nickel (Ni) and aluminium (Al) concentrations in female breast cancer and normal tissue. MATERIALS AND METHODS: The concentration of metals in 16 non-cancerous breast tissues and 67 breast cancer samples was measured by flame atomic absorption spectrometry. RESULTS: In the case of normal breast tissue the concentrations were 0.61 ± 0.24 µg Cd/g dry tissue, 1.84 ± 0.67 µg Ni/g dry tissue, and 3.63 ± 1.00 µg Al/g dry tissue, whereas in breast cancer concentrations of metals were 0.76 ± 0.38 µg/g dry tissue, 2.26 ± 0.79 µg/g dry tissue, and 4.40 ± 1.82 µg/g dry tissue, respectively. The concentration of Cd and Al in normal breast tissue was significantly lower than in breast cancer. In the case of Ni concentration, we did not observe statistically significant differences between normal and cancerous tissue. There were no significant differences in concentration of studied metals, in breast cancer, in the context of age, menopausal status, and cancer histological grading. CONCLUSION: The data obtained show higher concentration of cadmium and aluminium and support a possible relationship between those metals and breast cancer.

Significance of G Protein-Coupled Estrogen Receptor in the Pathophysiology of Irritable Bowel Syndrome, Inflammatory Bowel Diseases and Colorectal Cancer.

The regulatory role of estrogens and nuclear estrogen receptors, i. e., estrogen receptor α and ß has been reported in gastrointestinal diseases. However, the contribution of G protein-coupled estrogen receptor, the membrane-bound estrogen receptor, is still poorly understood. Unlike nuclear estrogen receptors, which are responsible for the genomic activity of estrogens, the G protein-coupled estrogen receptor affects the "rapid" non-genomic activity of estrogens, leading to modulation of many signaling pathways and ultimately changing gene expression. Recently, the crucial role of G protein-coupled estrogen receptor in intestinal pathogenesis has been documented. It has been shown that the G protein-coupled estrogen receptor can modulate the progression of irritable bowel syndrome, inflammatory bowel diseases such as Crohn's disease and ulcerative colitis as well as colorectal cancer. The G protein-coupled estrogen receptor appears to be a potent factor regulating abdominal sensitivity and pain, intestinal peristalsis, colitis development, proliferation and migration potential of colorectal cancer cells and seems to be a useful target in gastrointestinal diseases. In this review, we present the current state of knowledge about the contribution of the G protein-coupled estrogen receptor to irritable bowel syndrome, inflammatory bowel diseases and colorectal cancer.

Visualization of Estrogen Receptors in Colons of Mice with TNBS-Induced Crohn's Disease using Immunofluorescence.

Crohn's disease is the most diagnosed type of inflammatory bowel disease. Chronic inflammation developing in the intestine leads to peristalsis disorder and damage of intestinal mucosa and seems to be associated with an increased risk of colon neoplastic transformation. Accumulating evidence indicates that estrogens and estrogen receptors affect not only hormone-sensitive tissues, but also other tissues not directly related to estrogens, such as the lungs or colon. Here, we describe the protocol for the successful immunofluorescence staining of estrogen receptors in colon obtained from a murine model of TNBS-induced Crohn's disease. A detailed protocol for the induction of Crohn's disease in mice and intestine preparation is provided as well as a step-by-step immunohistochemical procedure using formalin-fixed paraffin-embedded intestine sections. The described methods are not only useful for estrogen receptor detection and estrogen signaling investigation in vivo but can also be applied to for other proteins which may be involved in the development of colitis.

Betaglycan Gene (TGFBR3) Polymorphism Is Associated with Increased Risk of Endometrial Cancer.

We investigated single nucleotide polymorphism (SNP) of the betaglycan gene (TGFBR3) encoding the TGFß co-receptor in endometrial cancer (EC) and its association with betaglycan expression. The study group included 153 women diagnosed with EC and 248 cancer-free controls. SNP genotyping and gene expression were analyzed using TaqMan probes. Three out of the eight SNPs tested, i.e., rs12566180 (CT; OR = 2.22; 95% CI = 1.15-4.30; p = 0.0177), rs6680463 (GC; OR = 2.34; 95% CI = 1.20-4.53; p = 0.0120) and rs2296621 (TT; OR = 6.40; 95% CI = 1.18-34.84; p = 0.0317) were found to be significantly associated with increased risk of EC (adjusted to age, body mass index, menarche and parity). Among the analyzed SNPs, only rs2296621 demonstrated the impact on the increased cancer aggressiveness evaluated by the WHO grading system (G3 vs. G1/2, GT-OR = 4.04; 95% CI = 1.56-10.51; p = 0.0026; T-OR = 2.38; 95% CI = 1.16-4.85; p = 0.0151). Linkage disequilibrium (LD) analysis revealed high LD (r2 ≥ 0.8) in two haploblocks, constructed by rs2770186/rs12141128 and rs12566180/rs6680463, respectively. In the case of C/C haplotype (OR = 4.82; 95% CI = 1.54-15.07; p = 0.0116-Bonferroni corrected) and T/G haplotype (OR = 3.25; 95% CI = 1.29-8.15; p = 0.0328-Bonferroni corrected) in haploblock rs12566180/rs6680463, significantly higher frequency was observed in patients with EC as compared to the control group. The genotype-phenotype studies showed that SNPs of the TGFBR3 gene associated with an increased risk of EC, i.e., rs12566180 and rs2296621 may affect betaglycan expression at the transcriptomic level (rs12566180-CC vs. TT, p < 0.01; rs2296621-GG vs. TT, p < 0.001, GT vs. TT, p < 0.05). Functional consequences of evaluated TGFBR3 gene SNPs were supported by RegulomeDB search. In conclusion, polymorphism of the TGFBR3 gene may be associated with an increased EC occurrence, as well as may be the molecular mechanism responsible for observed betaglycan down-regulation in EC patients.

Cyclic derivative of morphiceptin Dmt-cyclo-(D-Lys-Phe-D-Pro-Asp)-NH2(P-317), a mixed agonist of MOP and KOP opioid receptors, exerts anti-inflammatory and anti-tumor activity in colitis and colitis-associated colorectal cancer in mice.

Endogenous opioid system is involved in the maintenance of the intestinal homeostasis. Recently, we proved that stimulation of opioid receptors using P-317, a cyclic morphiceptin analog, resulted in the alleviation of acute colitis in mice. The aim of the current study was to assess the effect of P-317 during colitis and colitis-associated colorectal cancer in mice. Colitis was induced by addition of dextran sodium sulfate (DSS) into drinking water. Colitis-associated colorectal cancer was induced by a single intraperitoneal injection of azoxymethane (AOM) and subsequent addition of DSS into drinking water (week 2, 5, 8). During macroscopic damage evaluation the samples were collected and used for biochemical (MPO activity assay), molecular (qPCR and western blot) and histological studies. In experimental colitis, P-317 induced an anti-inflammatory response as indicated by macroscopic and microscopic scores. In the colitis-associated colorectal cancer model, a significant difference in colorectal tumor development was observed between vehicle- and P-317-treated mice. P-317 decreased the total number of colonic tumors and inhibited MPO activity. Hematoxylin and eosin staining confirmed anti-tumor activity of P-317. The expression of TNF-α was decreased in P-317-treated mice as compared to the vehicle-treated group. P-317 decreased proliferation as well as ß-catenin expression in tumors. P-317, a mixed MOP and KOP receptor agonist, induced an anti-inflammatory response in experimental colitis and decreased tumor development in colitis-associated colorectal cancer in mice.

Impact of EGFR immunoexpression on STAT3 activation and association with proinflammatory/regulatory cytokine pattern in laryngeal squamous cell carcinoma.

Stimulation of epidermal growth factor receptor (EGFR) results in the activation of signal transducer and activator of transcription-3 (STAT3), a transcriptional factor associated with carcinogenesis. Proinflammatory cytokines are capable of activating a tumor cell death program by reducing EGFR tyrosine phosphorylation. This study aimed to identify EGFR expression in laryngeal carcinoma and determine the relationship with STAT3 and proinflammatory/regulatory cytokine secretion. An analysis of EGFR expression (membranous EGFR-m and cytoplasmic EGFR-c) was performed in tumor tissues by immunohistochemical (IHC) staining in 45 medical cases of laryngeal carcinoma. STAT3 expression in freshly isolated tumor and non-cancerous normal epithelial cells by RT-PCR was analyzed in 24 patients after total larynx resection. The concentrations of TNFalpha, IL-2, IL-6, IL-8 and IFNgamma secreted by purified peripheral blood mononuclear cells (PBMCs) or contained in whole blood samples were measured by ELISA. The relationship between EGFR and mRNA STAT3 expression as well as the level of secreted cytokines was investigated. In our study, 93.3% tumors expressed EGFR-m and 37.8% EGFR-c. It also revealed a statistically significant dependence of the EGFR status on STAT3 expression in neoplastic tissues. Tumors with IHC EGFR-m positive staining >50% of the total number of cells, as well as with EGFR-c positive staining, were characterized by the most frequent presence of STAT3 expression. Our data demonstrate a significant negative relationship between EGFR-m expression and TNFalpha concentration, and a positive connection between membranous EGFR and IL-8 or IFNgamma levels recorded in isolated PBMCs. Furthermore, this study revealed a significant relationship between EGFR-c immunoexpression and IL-8 or IFNgamma concentration. Our findings have confirmed a key role of EGFR in determining the proliferative and malignant potential of laryngeal carcinoma.

G protein-coupled estrogen receptor in colon function, immune regulation and carcinogenesis.

Estrogens play important roles in the development and progression of multiple tumor types. Accumulating evidence points to the significance of estrogen action not only in tumors of hormonally regulated tissues such as the breast, endometrium and ovary, but also in the development of colorectal cancer (CRC). The effects of estrogens in physiological and pathophysiological conditions are mediated by the nuclear estrogen receptors α and ß, as well as the membrane-bound G protein-coupled estrogen receptor (GPER). The roles of GPER in CRC development and progression, however, remain poorly understood. Studies on the functions of GPER in the colon have shown that this estrogen receptor regulates colonic motility as well as immune responses in CRC-associated diseases, such as Crohn's disease and ulcerative colitis. GPER is also involved in cell cycle regulation, endoplasmic reticulum stress, proliferation, apoptosis, vascularization, cell migration, and the regulation of fatty acid and estrogen metabolism in CRC cells. Thus, multiple lines of evidence suggest that GPER may play an important role in colorectal carcinogenesis. In this review, we present the current state of knowledge regarding the contribution of GPER to colon function and CRC.

G protein-coupled estrogen receptor mediates anti-inflammatory action in Crohn's disease.

Estrogens exert immunomodulatory action in many autoimmune diseases. Accumulating evidence highlights the meaningful impact of estrogen receptors in physiology and pathophysiology of the colon. However, the significance of G protein-coupled estrogen receptor (GPER) on Crohn's disease (CD), one of the inflammatory bowel disease (IBD) types, is still elusive. Our study revealed GPER overexpression at the mRNA and protein levels in patients with CD. To evaluate the effects of GPER activation/inhibition on colitis development, a murine 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced model of CD was used. We showed that activation of GPER reduces mortality, improves macroscopic and microscopic scores and lowers C-reactive protein (CRP) level. The impact of estrogen signaling on the suppression of the intestinal inflammation was proved by immunohistochemistry. It was demonstrated that GPER activation is accompanied by modulation of extracellular-signal regulated kinase (ERK) signaling pathway and expression level of genes involved in signal transmission and immune response as well as the expression of some microRNAs (miR-145, miR-148-5p and miR-592). Our study revealed that the membrane-bound estrogen receptor GPER mediates anti-inflammatory action and seems to be a potent therapeutic target in maintaining remission in CD.

RAD51 and XRCC3 Polymorphisms Are Associated with Increased Risk of Prostate Cancer.

Genetic polymorphisms in DNA repair genes may affect DNA repair efficiency and may contribute to the risk of developing cancer. The aim of our study was to investigate single nucleotide polymorphisms (SNPs) in RAD51 (rs2619679, rs2928140, and rs5030789) and XRCC3 (rs1799796) involved in DNA double-strand break repair and their relationship to prostate cancer. The study group included 99 men diagnosed with prostate cancer and 205 cancer-free controls. SNP genotyping was performed using the PCR-RFLP method. A significant association was detected between RAD51 rs5030789 polymorphism and XRCC3 rs1799796 polymorphism and an increased risk of prostate cancer. Our results indicate that RAD51 and XRCC3 polymorphism may contribute to prostate cancer.

Systemic administration of serotonin exacerbates abdominal pain and colitis via interaction with the endocannabinoid system.

BACKGROUND AND AIMS: Molecular basis of abdominal pain in IBD is not fully characterized. Serotonin (5-HT) increases visceral pain severity and contributes to exacerbation of inflammation. Moreover, it is well established that decreased anandamide (AEA) signaling in the gut increases visceral pain severity. The aim of this study was to investigate the interplay between 5-HT and endocannabinoid signaling in colitis. METHODS: We used 3% DSS in drinking water to induce colitis in mice. From day 3 5-HT was administered for 5 days and each day visceromotor response to colorectal distention (CRD) was measured. Expression of cannabinoid (CB) receptors as well as enzymes responsible of biosynthesis and degradation of endocannabinoids were investigated. Moreover, endocannabinoid levels were assessed by mass spectrometry. Additionally, we measured the expression of enzymes synthesizing 5-HT and AEA in the colon of IBD patients and healthy controls. RESULTS: Chronic exposure to 5-HT increased visceromotor response to CRD and worsened colitis, which was associated with decrease of AEA via 5-HT3 and 5-HT4 receptors. Moreover, exposure to 5-HT led to the downregulation of CB1 receptors. Colonic levels of N-acyl-phosphatidylethanolamine-specific phospholipase D (NAPE-PLD), which is responsible for synthesis of AEA, significantly declined after chronic treatment with 5-HT and this effect was reversed by the 5-HT3 and 5-HT4 receptor antagonists. NAPE-PLD was also downregulated in the colon of UC patients. CONCLUSIONS: Our study shows a link between 5-HT and endocannabinoid signaling pathways in IBD. Thus, pharmacological blockade of 5-HT signaling or supplementation with endocannabinoids in the gut might be of benefit in severe cases of abdominal pain in IBD.

Dinucleotide repeat polymorphisms of RAD51, BRCA1, BRCA2 gene regions in breast cancer.

Recent studies suggest that genetic polymorphisms of the DNA repair genes have been implicated in breast cancer risk. BRCA1 and BRCA2, two breast cancer susceptibility genes, are essential to maintain chromosomal integrity. This is mediated via regulation of RAD51 during homologous recombination. Dinucleotide polymorphism repeats in the 15q14-21, 17q21 and 13q12-13 regions, where the RAD51, BRCA1 and BRCA2 genes are located, respectively, have been evaluated. The polymorphism was determined using the following microsatellite markers: D15S118, D15S214, D15S1006, D17S855, D17S1323, D13S260 and D13S290. Genotypes containing the (CA)(17) or (CA)(19) alleles in the RAD51 region were found to be associated with a decreased breast cancer risk. Genotype containing the (CA)(17) allele in the 13q12-13 region was found to be associated with an increased breast cancer risk. The results indicate that dinucleotide CA repeat polymorphism at RAD51 and BRCA2 gene regions might be associated with genetic susceptibility to breast cancer.

Estrogen signaling deregulation related with local immune response modulation in irritable bowel syndrome.

The etiology and pathogenesis underlying irritable bowel syndrome (IBS), a common gastrointestinal disorder are still unclear. Cumulating data suggest dysregulation of inflammatory and immune response pathways and changes of epithelial barrier function. The role of estrogens albeit varied, in responses of immune system is well documented. The aim of this study was to investigate estrogen receptors engagment in IBS subtypes, i.e. constipation predominant (IBS-C) and diarrhea predominant (IBS-D). Furthermore, we analyzed whether estrogen signaling is accompanied by alteration in expression of pro- and anti-inflammatory cytokines and microRNAs that can regulate among others genes involved in immune responses. It was found that estrogen receptor α (ERα) and G protein-coupled estrogen receptor (GPER) expression is up-regulated in IBS while estrogen receptor ß (ERß) appears to be down-regulated at mRNA but up-regulated at the protein level. When gender and female age were included statistically significant overexpression of ERα in IBS-D women under the age of 50, while of GPER in IBS-D men was stated. In all studied IBS samples disturbances in expression of cytokines IL-6, IL-10 and TNF-α as well as miR-145, miR-148-5p and miR-592 were observed. This research reveals the association of estrogen receptors with IBS. Simultaneous alterations of studied immunomodulatory cytokines and microRNAs suggest that in IBS dysregulation of local immune response may involve estrogen-dependent way.