Placental Expression of Glucose and Zinc Transporters in Women with Gestational Diabetes.

Background/Objectives: Gestational diabetes (GDM) is a metabolic disorder with altered glucose levels diagnosed in pregnant women. The pathogenesis of GDM is not fully known, but it is thought to be caused by impaired insulin production and insulin resistance induced by diabetogenic factors. The placenta may play an important role in the development of GDM. Glucose transporters (GLUTs) are responsible for the delivery of glucose into the foetal circulation. Placental zinc transporters regulate insulin and glucagon secretion, as well as gluconeogenesis and glycolysis. The aim of this study was to investigate the placental expression of GLUT3, GLUT4, GLUT7 and SLC30A8 in women with GDM. Furthermore, we evaluated whether the expression profiles of these transporters were correlated with clinical parameters. Methods: This study included 26 patients with GDM and 28 patients with normal glucose tolerance (NGT). Results: The placental expression of GLUT3 was significantly reduced in the GDM group, while the placental expression of GLUT4, GLUT7 and SLC30A8 was significantly upregulated in the GDM group. GLUT3 expression correlated significantly with body mass index (BMI) increase during pregnancy and body mass increase during pregnancy, while GLUT4 expression correlated negatively with BMI at birth. Conclusions: These results suggest the involvement of GLUT3 and GLUT4, GLUT7 and SLC30A8 in the pathogenesis of GDM.

The effect of plasma cytokines on the expression of adiponectin and its receptors in the synovial membrane of joints and the infrapatellar fat pad in patients with rheumatoid arthritis and osteoarthritis.

BACKGROUND: Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that leads to joint destruction. Numerous pro-inflammatory mediators, including adipokines, play an important role in the pathogenesis of RA. OBJECTIVE: The aim of the study was to investigate the relationships between selected plasma cytokines and expression of adiponectin and its receptors in the synovium and the infrapatellar fat pad in patients with RA and osteoarthritis (OA). METHODS: Blood, synovium and fat pad samples from 18 patients with RA and 18 with OA were collected during joint replacement surgery. Spearman rank correlations between plasma concentrations of selected cytokines (IL-1ß, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 p40, IL-13, IL-17, G-CSF and GM-CSF) and the expression of adiponectin and its receptors were determined. Plasma levels of cytokines were determined using a magnetic bead-based multiplex assay, mRNA expression of adiponectin and its receptors were determined by real-time PCR. RESULTS: In OA patients, there were significant positive correlations between adiponectin expression in the synovial membrane and plasma levels of IL-1ß, IL-4, G-CSF and GM-CSF, as well as a significant positive correlation between adiponectin expression in the fat pad and plasma levels of GM-CSF. In addition, OA patients showed significant negative correlations between AdipoR1 and AdipoR2 expression in the synovial membrane and plasma IL-6 levels, as well as between AdipoR2 expression in the synovial membrane and plasma MCP-1 and TNF-α levels. In patients with RA, there were no significant correlations between adiponectin expression in the synovial membrane and infrapatellar fat pad and plasma levels of the cytokines studied. In addition, RA patients showed a statistically significant negative correlation between AdipoR1 expression in the synovial membrane and plasma levels of TNF-α, IL-7, IL-12 and IL-13, and a significant negative correlation between AdipoR1 expression in the infrapatellar fat pad and plasma levels of IL-1ß. CONCLUSIONS: Adiponectin and its receptors showed the correlations with several plasma cytokines, however, a thorough understanding of the role of adiponectin in RA and OA requires further investigation.

Human macrophage immunometabolism regulator (MACIR) in patients with periodontitis.

OBJECTIVE: Periodontitis is a local inflammatory reaction caused by bacterial infection in which immune cells, including macrophages, are involved. Recent studies have shown that an important regulator of macrophage function is the human macrophage immunometabolism regulator (MACIR). This gene has been shown to play a key role in modulating the immune response by affecting the activity of fibroblasts and macrophages. In this study, we investigated the expression of MACIR in the gingival tissues of patients with periodontal disease, as well as the effect of IL-1ß and TNF-α on the expression of MACIR gene and protein in human gingival fibroblasts. METHODS: MACIR mRNA expression in gingival tissue samples was determined using Real-time PCR. Expression of MACIR protein was determined using immunofluorescent staining and western blotting. RESULTS: The MACIR mRNA expression in gingival tissue samples in patients with periodontitis was statistically significantly lower than in gingival tissue samples from healthy controls (p = 0.009). The stimulation of human gingival fibroblasts with IL-1ß and TNF-α resulted in a statistically significant decrease of MACIR gene mRNA expression. In western blotting and immunofluorescent analysis, we confirmed that the stimulation of the primary culture of human gingival fibroblasts by both IL-1ß and TNF-α decreases the expression of MACIR protein. CONCLUSION: The results of the study suggest that MACIR is an important regulator of the inflammatory process in patients with periodontitis. Decreased expression of the MACIR gene may activate macrophages to secrete mediators that increase inflammation and cause periodontal tissue destruction.

Expression of Interleukin 17A and 17B in Gingival Tissue in Patients with Periodontitis.

Periodontitis (PD) is a chronic inflammatory disease that is initiated by oral microorganisms. The pathogens induce the production of cytokines, such as interleukin (IL)-17, which enhances the inflammatory response and progression of the disease. The aim of this study was to examine the expression and localization in gingival tissue of IL-17A and IL-17B in patients with periodontitis. This study included 14 patients with periodontal disease and 14 healthy subjects without periodontal disease as a control group. There were no statistically significant differences in the expression of IL-17A mRNA between patients with periodontitis and control subjects. The expression of IL-17B mRNA was statistically significantly lower in patients with periodontitis in comparison with healthy subjects (p < 0.048). The expression of IL-17A correlated significantly with the approximal plaque index. The IL-17B expression in gingival tissue correlated with the clinical attachment level. This correlation reached borderline statistical significance (p = 0.06). In immunohistochemical analysis, we have shown the highest expression of IL-17 protein in inflamed connective tissue, epithelium, and granulation tissue from gingival biopsy specimens from patients with periodontitis. In biopsy specimens from healthy individuals, no IL-17 was found in the epithelium, while an expression of IL-17 was found in the connective tissue. The results of our study confirm the involvement of IL-17 in the pathogenesis of periodontitis. Our results suggest that an increase in IL-17 protein expression in the gingival tissue of patients with periodontitis occurs at the post-translational stage.

COBLL1 and IRS1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes.

Gestational diabetes mellitus (GDM) is carbohydrate intolerance in pregnant women leading to various complications. Currently, there is a search for factors predisposing to GDM. Among them are genetic polymorphisms of genes involved in insulin secretion as well as carbohydrate metabolism. Due to the similar pathogenesis of GDM to type 2 diabetes (T2DM), genetic polymorphisms associated with T2DM are considered. The aim of this study was to examine the associations between the COBLL1 rs7607980 T > C and IRS1 rs2943641 T > C gene polymorphisms and the risk of GDM as well as selected clinical parameters in women with GDM. Additionally, we examined the expression of these genes in the placenta of women with and without GDM in correlation with selected clinical parameters. This study included 328 pregnant women with normal glucose tolerance (NGT) and 251 pregnant women with GDM diagnosed on the basis of a 75 g oral glucose tolerance test (OGTT) at 24−28 weeks gestation. There were no statistically significant differences in the distribution of IRS1 rs2943641 gene polymorphisms between women with GDM and pregnant women with NGT. In the GDM group, we observed a decreased frequency of COBLL1 rs7607980 CC homozygous women (CC vs. TC+TT, p = 0.048); however, there was no statistically significant difference in the frequency of alleles between women with GDM and the control group. There were no statistically significant associations between COBLL1 rs7607980 gene polymorphism and clinical parameters in women with GDM. In GDM women with the IRS1 rs2943641 TT genotype, fasting glucose levels were significantly higher than in women with CC and TC genotypes. There was no statistically significant difference in the expression of COBLL1 and IRS1 genes in the placenta between women with GDM and healthy women. There were no statistically significant correlations between COBLL1 gene expression in the placenta and clinical parameters. The expression of IRS1 correlated significantly with an increase in BMI during pregnancy. The results of this study suggest that COBLL1 rs7607980 and IRS1 rs2943641 gene polymorphisms are not significant risk factors for GDM in our population. The IRS1 TT genotype may be associated with higher fasting glucose levels in women with GDM. Expression of the IRS1 gene in the placenta positively correlates with an increase in BMI during pregnancy in women with GDM.

KCNJ11 and KCNQ1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) represents carbohydrate intolerance in pregnant women. The pathogenesis of GDM is very complex, but abnormalities in insulin production and secretion underlie the disease. Potassium channels play an important role in insulin production and secretion. The family of potassium channels includes (among others) the potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) and voltage-gated K+ channel (KCNQ1). The aim of the study was to examine the distribution of the KCNJ11 rs5219 and KCNQ1 rs151290 and rs2237892 gene polymorphisms in women with GDM and pregnant women with normal carbohydrate tolerance, to verify whether these polymorphisms are risk factors for GDM. This study included 204 Caucasian pregnant women with GDM and 207 pregnant women with normal glucose tolerance (NGT) from the West Pomeranian region of Poland. The diagnosis of GDM was based on a 75 g oral glucose tolerance test (OGTT) at 24-28 weeks gestation. There were no statistically significant differences in distribution of the KCNJ11 rs5219 and KCNQ1 rs151290 and rs2237892 gene polymorphisms between women with GDM and pregnant women with normal carbohydrate tolerance. Moreover, there were no statistically significant associations between the studied genotypes and the selected clinical parameters in women with GDM. The results of our study suggest that the KCNJ11 rs5219 and KCNQ1 rs2237892 and rs151290 gene polymorphisms are not significant risk factors associated with the development of GDM in our population. There were also no differences in the expression of KCNJ11 and KCNQ1 genes in the placenta of women with GDM and normal carbohydrate tolerance. However, an association between KCNJ11 gene expression in placenta and APGAR score in newborns was found.

Adiponectin Is a Component of the Inflammatory Cascade in Rheumatoid Arthritis.

Adiponectin is a secretory protein of adipocytes that plays an important role in pathological processes by participation in modulating the immune and inflammatory responses. The pro-inflammatory effect of adiponectin is observed in rheumatoid arthritis (RA). In this study, we examined adiponectin plasma levels and the expression of adiponectin in bone marrow tissue samples, synovium samples, and infrapatellar fat pad samples from patients with osteoarthritis (OA) and RA. Additionally we examined the expression of adiponectin receptors AdipoR1 and AdipoR2 in synovium samples and infrapatellar fat pad samples from patients with OA and RA. We also assessed the correlations between adiponectin plasma concentrations, adiponectin expression in bone marrow, synovium, infrapatellar fat pad, and plasma levels of selected cytokines. We found increased expression of adiponectin in synovium samples and infrapatellar fat pad samples from patients with RA as compared to patients with OA. There were no statistically significant differences of adiponectin plasma levels and adiponectin expression in bone marrow tissue samples between OA and RA patients. There were no differences in the expression of AdipoR1 and AdipoR2 at the mRNA level in synovial tissue and the infrapatellar fat pad between RA and OA patients. However, in immunohistochemical analysis in samples of the synovial membrane from RA patients, we observed very strong expression of adiponectin in intima cells, macrophages, and subintimal fibroblasts, such as synoviocytes, vs. strong expression in OA samples. Very strong expression of adiponectin was also noted in adipocytes of Hoffa's fat pad of RA patients. Expression of AdipoR1 was stronger in RA tissue samples, while AdipoR2 expression was very similar in both RA and OA samples. Our results showed increased adiponectin expression in the synovial membrane and Hoffa's pad in RA patients compared to that of OA patients. However, there were no differences in plasma adiponectin concentrations and its expression in bone marrow. The results suggest that adiponectin is a component of the inflammatory cascade that is present in RA. Pro-inflammatory factors enhance the expression of adiponectin, especially in joint tissues-the synovial membrane and Hoffa's fat pad. In turn, adiponectin also increases the expression of further pro-inflammatory mediators.

THADA, SDHAF4, and MACF1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes.

Gestational diabetes mellitus (GDM) is a metabolic disorder in pregnant women leading to various complications. Consequently, factors predisposing its development are being sought. Previous studies have shown that the pathogenesis of GDM is similar to that of type 2 diabetes, and it is therefore thought that the two diseases may have a common genetic basis. The aim of this study was to examine the associations between thyroid adenoma-associated (THADA) rs7578597 T>C, succinate dehydrogenase complex assembly factor 4 (SDHAF4) rs1048886 A>G, and microtubule-actin crosslinking factor 1 (MACF1) rs2296172 A>G gene polymorphisms and the risk of GDM development as well as selected clinical parameters in women with GDM. We also examined the expression of these genes in the placenta of women with and without GDM in association with clinical parameters. This case-control study included 272 pregnant women with GDM and 348 pregnant women with normal glucose tolerance. There were no statistically significant differences in the distribution of the THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G gene polymorphisms between pregnant control women and women with GDM. The associations between clinical parameters such as body mass before pregnancy, body mass at birth, body mass increase during pregnancy, BMI before pregnancy, BMI at birth, BMI increase during pregnancy, glycated hemoglobin (HbA1c), daily insulin requirement, childbirth time, and newborn body mass and APGAR score, and the THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G genotypes were statistically non-significant. We only observed lower values of body mass before pregnancy and body mass at birth in women with the SDHAF4 rs1048886 AG genotype in comparison with AA genotype carriers. There was no statistically significant difference in the expression of THADA, SDHAF4, and MACF1 genes in the placenta between women with GDM and healthy women. There were also no statistically significant correlations between THADA, SDHAF4, and MACF1 gene expression in the placenta and clinical parameters. The results of our study suggest that THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G gene polymorphisms are not significant factors associated with GDM onset. In addition, SDHAF4 rs1048886 A>G may be associated with body mass before pregnancy and body mass at birth in pregnant women.

ADCY5, CAPN10 and JAZF1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes.

Gestational diabetes mellitus (GDM) is carbohydrate intolerance that occurs during pregnancy. This disease may lead to various maternal and neonatal complications; therefore, early diagnosis is very important. Because of the similarity in pathogenesis of type 2 diabetes and GDM, the genetic variants associated with type 2 diabetes are commonly investigated in GDM. The aim of the present study was to examine the associations between the polymorphisms in the ADCY5 (rs11708067, rs2877716), CAPN10 (rs2975760, rs3792267), and JAZF1 (rs864745) genes and GDM as well as to determine the expression of these genes in the placenta. This study included 272 pregnant women with GDM and 348 pregnant women with normal glucose tolerance. The diagnosis of GDM was based on a 75 g oral glucose tolerance test (OGTT) at 24-28 weeks gestation, according to International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. There were no statistically significant differences in the distribution of the ADCY5 gene (rs11708067, rs2877716) and CAPN10 gene (rs2975760, rs3792267) polymorphisms between pregnant women with normal carbohydrate tolerance and pregnant women with GDM. We have shown a lower frequency of JAZF1 gene rs864745 C allele carriers among women with GDM CC + CT vs. TT (OR = 0.60, 95% CI = 0.41-0.87, p = 0.006), and C vs. T (OR = 0.75, 95% CI = 0.60-0.95, p = 0.014). In addition, ADCY5 and JAZF1 gene expression was statistically significantly increased in the placentas of women with GDM compared with that of healthy women. The expression of the CAPN10 gene did not differ significantly between women with and without GDM. Our results indicate increased expression of JAZF1 and ADCY5 genes in the placentas of women with GDM as well as a protective effect of the C allele of the JAZF1 rs864745 gene polymorphism on the development of GDM in pregnant women.

The Role of MECP2 and CCR5 Polymorphisms on the Development and Course of Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic and systemic autoimmune disease. SLE is described by production of autoantibodies and causes damage of many organs. T-cells play a crucial role in SLE pathogenesis. T-cells intensify inflammation through a number of processes, which leads to autoimmunization. CCR5 and MECP2 genes are linked with T-cells and pathogenesis of SLE. Polymorphisms in these genes are related with the prognostic factors of risk of disease onset and disease severity. The aim of this study was to estimate the influence of polymorphisms in MECP2 and CCR5 genes on the development and course of systemic lupus erythematosus. We examined 137 SLE patients and 604 healthy controls. We studied polymorphisms for CCR5 gene: rs333 and for MECP2: rs2075596, rs1734787, rs17435, and rs2239464. We genotyped our MECP2 samples and we performed a restriction fragment length polymorphism (RFLP) analysis for CCR5 samples. We showed a risk factor for allele T in rs17435 and for allele A in rs2075596 in MECP2. We noticed that MECP2 rs2075596 G/A, rs1734787 C/A, rs17435 A/T, and rs2239464 G/A polymorphisms are more prevalent in SLE patients than in healthy controls. We believe that above-mentioned MECP2 polymorphisms can be considered as SLE susceptibility factor.

Mannose binding lectin 2 gene polymorphisms in patients after renal transplantation with acute graft rejection.

Mannose binding lectin 2 (MBL2) is one of the pattern-recognition soluble receptors and is responsible for complement activation via the lectin pathway, so it plays an important role in kidney transplantation. The aim of the study was to examine the association between MBL2 gene polymorphisms and acute rejection of the kidney allograft. This study enrolled 266 Caucasian deceased-donor renal transplant recipients - 69 with diagnosed acute graft rejection, 197 with stable graft function. A 969 bp DNA fragment, from chromosome 10, including promoter region and exon 1 of MBL2 gene was sequenced. The DNA fragment obtained contained 122 SNPs accordingly to the NCBI dbSNP database. Of this number only nine showed variation within our population (rs36014597, rs5030737, rs1800450, rs7095891, rs11003123, rs7096206, rs7084554, rs11003124, rs11003125), and only these were subjected to further analysis. Among the studied polymorphisms in the MBL2 gene only rs1800450 polymorphism was statistically significantly associated with kidney allograft rejection. The AA genotype was significantly associated with an increased risk of acute kidney allograft rejection. (AA vs GA+GG: OR=9.29 (95%CI: 1.83-47.17), p=0.005). The results of our study indicate that MBL2 gene rs1800450 polymorphism may be associated with the risk of acute kidney allograft rejection. The AA genotype, associated with lower MBL2 expression, may be associated with an increased risk of acute kidney allograft rejection.

Ficolin-2 Gene rs7851696 Polymorphism is Associated with Delayed Graft Function and Acute Rejection in Kidney Allograft Recipients.

Ficolin-2 is an activator of the complement system that acts via the lectin pathway. Complement activation plays a substantial role in the renal injury inherent to kidney transplantation. In this study, we examined the associations between ficolin-2 gene polymorphisms in exon 8 and kidney allograft function. This study comprised 270 Caucasian deceased-donor renal transplant recipients. The following parameters were recorded in each case: delayed graft function (DGF), acute rejection (AR), and chronic allograft dysfunction. Among patients with DGF, we observed a significantly increased frequency of rs7851696 GT and TT genotypes as well as T allele (TT + GT vs GG OR 1.98, 95% CI 1.12-3.48, p = 0.02; T vs G OR 2.08, 95% CI 1.27-3.41, p = 0.005). There was also an increased frequency of rs4521835 GG and TG genotypes as well as G alleles; however, these differences were on the borderline of statistical significance (GG + TG vs TT, OR 1.75, 95% CI 0.98-3.12, p = 0.07; G vs T OR 1.45, 95% CI 1.00-2.09, p = 0.050). In addition, we observed an increased frequency of acute allograft rejection in carriers of ficolin-2 rs7851696 T alleles on the borderline of statistical significance (TT + GT vs GG OR 1.75, 95% CI 0.97-3.16, p = 0.08), but the frequency of T allele was significantly higher in patients with AR (T vs G OR 1.71, 95% CI 1.02-2.87, p = 0.048). The results of our study suggest that ficolin-2 rs7851696 gene polymorphism influences kidney allograft functions, with T allele increasing the risk of DGF and AR.

MMP1 and MMP3 gene polymorphisms in patients with acute coronary syndromes.

Matrix metalloproteinases (MMPs) are the group of proteolytic enzymes that break down the components of the connective tissue matrix leading to unstable atherosclerotic plaques. The aim of this study was to examine the association between MMP1-1607dupG (rs1799750) and MMP3-1171dupA (rs3025058) gene polymorphisms and acute coronary syndromes (ACS) in the form of unstable angina. This study included 197 patients with ACS in the form of unstable angina confirmed by coronary angiography (defined by >70% stenosis in at least one major coronary artery) and 144 healthy controls. There was no statistically significant difference in the distribution of the MMP1-1607dupG (rs1799750) polymorphism between patients with unstable angina and the control group. With regard to the MMP3-1171dupA (rs3025058) polymorphism, a significant increase in the frequency of the 6A/6A genotype among patients with unstable angina was detected. This association was confirmed in multivariate logistic regression analysis, where male sex and rs3025058 6A/6A genotype were significantly associated with an increased risk of ACS. © 2017 IUBMB Life, 69(11):850-855, 2017.

Expression of Cancer Testis Antigens in Colorectal Cancer: New Prognostic and Therapeutic Implications.

Background. While cancer/testis antigens (CTAs) are restricted in postnatal tissues to testes and germ line-derived cells, their role in cancer development and the clinical significance of their expression still remain to be better defined. Objective. The aim of this study was to investigate the level of CTA expression in colon samples from patients with colorectal cancer (CRC) in relation to patient clinical status. Methods. Forty-five patients with newly diagnosed colorectal cancer were included in the study. We selected a panel of 18 CTAs that were previously detected in CRC as well as some new gene candidates, and their expression was detected at the mRNA level by employing RQ-PCR. Additionally, we evaluated CTA expression in three colon cancer cell lines (CL-188, HTB-39, and HTB-37) after exposure to the DNA methylation-modifying drug 5-azacytidine. Results. We report that 6 out of 18 (33%) CTAs tested (MAGEA3, OIP5, TTK, PLU1, DKKL1, and FBXO39) were significantly (p < 0.05) overexpressed in tumor tissue compared with healthy colon samples isolated from the same patients. Conclusions. Moreover, we found that MAGEA3, PLU-1, and DKKL expression positively correlated with disease progression, evaluated according to the Dukes staging system. Finally, 5-azacytidine exposure significantly upregulated expression of CTAs on CRC cells, which indicates that this demethylation agent could be employed therapeutically to enhance the immune response against tumor cells.

IL17A and IL17F gene polymorphisms in patients with rheumatoid arthritis.

BACKGROUND: Interleukin-17 plays important role in the pathogenesis of rheumatoid arthritis (RA). The aim of this study was to examine the associations between polymorphisms in the IL17A and IL17F genes and RA. METHODS: We examined 422 RA patients and 337 subjects as a control group. Single nucleotide polymorphism (SNP) in the IL17A (rs2275913) and IL17F (rs763780, rs11465553, rs2397084) genes were genotyped using TaqMan genotyping assays from Life Technologies Genomic. RESULTS: There were no significant differences in distribution of IL17A and IL17F genotypes and alleles between RA patients and control group. There were no significant associations between IL17A and IL17F genotypes and age of disease diagnosis rheumatoid factor, erosive disease as well as extra-articular manifestations. CONCLUSIONS: The results of this study suggest, that IL17A and IL17F gene polymorphism are not the important factors associated with susceptibility and some clinical parameters of RA in a Polish population.

The effect of gene polymorphisms on patient responses to rheumatoid arthritis therapy.

INTRODUCTION: Rheumatoid arthritis (RA) is a systemic disease leading to joint destruction. The therapy of RA is mainly based on disease-modifying anti-rheumatic drugs (DMARDs) and biological drugs. The response to treatment is different among patients. Therefore, we have searched for factors that may predict the efficacy and toxicity during therapy in individual patients. AREAS COVERED: This review presents the role of genetic polymorphisms as predictors of the efficacy and toxicity during the therapy of RA patients with DMARDs (methotrexate, leflunomide, sulfasalazine) and biological drugs (anti-TNF-alpha antagonists, Tocilizumab, Rituximab). EXPERT OPINION: Despite studies having shown an association between genetic polymorphisms and response to therapy in RA patients, the majority of these findings are still inconclusive and inconsistent. We are still far from applying pharmacogenetic tests in routine clinical practice that can predict the outcome of treatment. Several factors, such as small sample size with low statistical power, variability in the outcome definitions and the heterogeneity of the cohorts, limited number of tested single nucleotide polymorphisms (SNPs), small effect for the selected variant, and a lack of consideration of epigenetic factors, may contribute to the inconsistency observed and may lead to limited success in personalizing therapy.

5­Azacytidine inhibits human rhabdomyosarcoma cell growth by downregulating insulin­like growth factor 2 expression and reactivating the H19 gene product miR­675, which negatively affects insulin­like growth factors and insulin signaling.

Insulin-like growth factor 2 (IGF2) and 1 (IGF1) and insulin (INS) promote proliferation of rhabdomyosarcoma (RMS) cells by interacting with the insulin-like growth factor 1 receptor (IGF1R) and the insulin receptor (INSR). Loss of imprinting (LOI) by DNA hypermethylation at the differentially methylated region (DMR) for the IGF2­H19 locus is commonly observed in RMS cells and results in an increase in the expression of proliferation-promoting IGF2 and downregulation of proliferation-inhibiting non-coding H19 miRNAs. One of these miRNAs, miR­675, has been reported in murine cells to be a negative regulator of IGF1R expression. To better address the role of IGF2 and 1, as well as INS signaling in the pathogenesis of RMS and the involvement of LOI at the IGF2­H19 locus, we employed the DNA demethylating agent 5­azacytidine (AzaC). We observed that AzaC­mediated demethylation of the DMR at the IGF2­H19 locus resulted in downregulation of IGF2 and an increase in the expression of H19. This epigenetic change resulted in a decrease in RMS proliferation due to downregulation of IGF2 and, IGF1R expression in an miR­675­dependent manner. Interestingly, we observed that miR­675 not only inhibited the expression of IGF1R in a similar manner in human and murine cells, but we also observed its negative effect on the expression of the INSR. These results confirm the crucial role of LOI at the IGF2­H19 DMR in the pathogenesis of RMS and are relevant to the development of new treatment strategies.

[Molecular mechanisms regulating metastasis of cancer cells with special emphasis on rhabdomyosarcoma]. / Molekularne mechanizmy regulacji przerzutowania komórek nowotworowych na przykladzie miesaka prazkowanokomórkowego (rhabdomyosarcoma)

Rhabdomyosarcoma (RMS) is a malignant tumor of soft tissue derived from embryonic mesenchymal and/or neuroectodermal tissues. It is most often associated with other genetic syndromes such as Li-Fraumeni or Bechwith-Wiedeman. RMS cells show morphological similarities to striated muscle and the presence of specific markers of muscle tissue. At the histological level, it is divided into two subtypes (alveolar RMS - ARMS and embryonal RMS - ERMS), which differ in their genetic background, and prognosis. In recent years there has been significant progress in understanding the mechanisms that regulate RMS cell growth and metastasis. Recently, a number of several chemokines, cytokines or growth factors and their receptors were identified involved in RMS pathogenesis as well as animal models of this tumor have been developed. This knowledge is of great importance in the development of potential therapeutic strategies not only in RMS, but also other types of cancer. This paper will discuss the theories of the origin of this rare tumor and the molecular mechanisms involved in its growth and metastasis. The processes and mechanisms described herein, such as chemotaxis, adhesion, proliferation, intracellular signal transduction, seem to universal for number of cancer types.