RESUMO
The transcription factor forkhead box protein 3 (FOXP3) is considered to be a prominent component of the immune system expressed in regulatory T cells (Tregs). Tregs are immunosuppressive cells that regulate immune homeostasis and self-tolerance. FOXP3 was originally thought to be a Tregs-specific molecule, but recent studies have pinpointed that FOXP3 is expressed in a diversity of benign tumors and carcinomas. The vast majority of the data have shown that FOXP3 is correlated with an unfavorable prognosis, although there are some reports indicating the opposite function of this molecule. Here, we review recent progress in understanding the FOXP3 role in the immunogenetic architecture of lung cancer, which is the leading cause of cancer-related death. We discuss the prognostic significance of tumor FOXP3 expression, tumor-infiltrating FOXP3-lymphocytes, tumor FOXP3 in tumor microenvironments and the potential of FOXP3-targeted therapy.
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Fatores de Transcrição Forkhead , Neoplasias Pulmonares , Linfócitos T Reguladores , Microambiente Tumoral , Humanos , Fatores de Transcrição Forkhead/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Prognóstico , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismoRESUMO
DNA damage response (DDR) is a complex process, essential for cell survival. Especially deleterious type of DNA damage are DNA double-strand breaks (DSB), which can lead to genomic instability and malignant transformation if not repaired correctly. The central player in DSB detection and repair is the ATM kinase which orchestrates the action of several downstream factors. Recent studies have suggested that long non-coding RNAs (lncRNAs) are involved in DDR. Here, we aimed to identify lncRNAs induced upon DNA damage in an ATM-dependent manner. DNA damage was induced by ionizing radiation (IR) in immortalized lymphoblastoid cell lines derived from 4 patients with ataxia-telangiectasia (AT) and 4 healthy donors. RNA-seq revealed 10 lncRNAs significantly induced 1â¯h after IR in healthy donors, whereas none in AT patients. 149 lncRNAs were induced 8â¯h after IR in the control group, while only three in AT patients. Among IR-induced mRNAs, we found several genes with well-known functions in DDR. Gene Set Enrichment Analysis and Gene Ontology revealed delayed induction of key DDR pathways in AT patients compared to controls. The induction and dynamics of selected 9 lncRNAs were confirmed by RT-qPCR. Moreover, using a specific ATM inhibitor we proved that the induction of those lncRNAs is dependent on ATM. Some of the detected lncRNA genes are localized next to protein-coding genes involved in DDR. We observed that induction of lncRNAs after IR preceded changes in expression of adjacent genes. This indicates that IR-induced lncRNAs may regulate the transcription of nearby genes. Subcellular fractionation into chromatin, nuclear, and cytoplasmic fractions revealed that the majority of studied lncRNAs are localized in chromatin. In summary, our study revealed several lncRNAs induced by IR in an ATM-dependent manner. Their genomic co-localization and co-expression with genes involved in DDR suggest that those lncRNAs may be important players in cellular response to DNA damage.
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Ataxia Telangiectasia , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Dano ao DNA , Cromatina , Linhagem Celular , Proteínas Mutadas de Ataxia TelangiectasiaRESUMO
The transcription factor MYC is a proto-oncogene with a well-documented essential role in the pathogenesis and maintenance of several types of cancer. MYC binds to specific E-box sequences in the genome to regulate gene expression in a cell-type- and developmental-stage-specific manner. To date, a combined analysis of essential MYC-bound E-boxes and their downstream target genes important for growth of different types of cancer is missing. In this study, we designed a CRISPR/Cas9 library to destroy E-box sequences in a genome-wide fashion. In parallel, we used the Brunello library to knock out protein-coding genes. We performed high-throughput screens with these libraries in four MYC-dependent cancer cell lines-K562, ST486, HepG2, and MCF7-which revealed several essential E-boxes and genes. Among them, we pinpointed crucial common and cell-type-specific MYC-regulated genes involved in pathways associated with cancer development. Extensive validation of our approach confirmed that E-box disruption affects MYC binding, target-gene expression, and cell proliferation in vitro as well as tumor growth in vivo. Our unique, well-validated tool opens new possibilities to gain novel insights into MYC-dependent vulnerabilities in cancer cells.
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Sistemas CRISPR-Cas , Neoplasias , Humanos , Sistemas CRISPR-Cas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Linhagem Celular , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica , Neoplasias/genéticaRESUMO
INTRODUCTION: The inactivation of both alleles of the ATM gene leads to ataxia-telangiectasia syndrome, whereas carriers of monoallelic mutations in the ATM gene are associated with increased risk of different types of cancer. Three substitutions in the ATM gene (c.6095G>A, c.7630-2A>C, c.5932G>T) are the most common mutations causing ataxia-telangiectasia among Polish patients. The aim of this study was to determine whether these ATM mutations are associated with increased risk of tobacco-related cancers. MATERIAL AND METHODS: 783 Polish patients with tobacco-related cancers were included in the study (468 with lung cancer, 153 with a single laryngeal cancer, 86 with multiple primary tumors localized in the larynx and 76 multiple primary tumors localized in the head or neck). The control group consisted of 464 healthy subjects from the Polish population. Three ATM mutations - c.5932G>T, c.6095G>A, c.7630-2A>C - were tested among selected patients. Molecular analyses were performed using high resolution melting analysis and restriction fragment length polymorphism. RESULTS: In the present study, we detected only one mutation, c.7630-2A>C, and no carriers of c.5932G>T, c.6095G>A mutations in the ATM gene among Polish patients with tobacco-related cancers. A patient with c.7630-2A>C mutation was diagnosed with lung adenocarcinoma, the most common type of lung cancer. One carrier of c.6095G>A mutation was found in the control group. CONCLUSIONS: The results indicate that the studied ATM variants do not seem to be associated with tobacco-related cancers in Poland.
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Hypoxia in non-small cell lung cancer (NSCLC) affects cancer progression, metastasis and metabolism. We previously showed that FAM13A was induced by hypoxia in NSCLC but the biological function of this gene has not been fully elucidated. This study aimed to investigate the role of hypoxia-induced FAM13A in NSCLC progression and metastasis. Lentiviral shRNAs were used for FAM13A gene silencing in NSCLC cell lines (A549, CORL-105). MTS assay, cell tracking VPD540 dye, wound healing assay, invasion assay, BrdU assay and APC Annexin V staining assays were performed to examine cell proliferation ability, migration, invasion and apoptosis rate in NSCLC cells. The results of VPD540 dye and MTS assays showed a significant reduction in cell proliferation after FAM13A knockdown in A549 cells cultured under normal and hypoxia (1% O2) conditions (p < 0.05), while the effect of FAM13A downregulation on CORL-105 cells was observed after 96 h exposition to hypoxia. Moreover, FAM13A inhibition induced S phase cell cycle arrest in A549 cells under hypoxia conditions. Silencing of FAM13A significantly suppressed migration of A549 and CORL-105 cells in both oxygen conditions, especially after 72 and 96 h (p < 0.001 in normoxia, p < 0.01 after hypoxia). It was showed that FAM13A reduction resulted in disruption of the F-actin cytoskeleton altering A549 cell migration. Cell invasion rates were significantly decreased in A549 FAM13A depleted cells compared to controls (p < 0.05), mostly under hypoxia. FAM13A silencing had no effect on apoptosis induction in NSCLC cells. In the present study, we found that FAM13A silencing has a negative effect on proliferation, migration and invasion activity in NSCLC cells in normal and hypoxic conditions. Our data demonstrated that FAM13A depleted post-hypoxic cells have a decreased cell proliferation ability and metastatic potential, which indicates FAM13A as a potential therapeutic target in lung cancer.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/secundário , Proteínas Ativadoras de GTPase/metabolismo , Regulação Neoplásica da Expressão Gênica , Hipóxia/fisiopatologia , Neoplasias Pulmonares/patologia , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ciclo Celular , Movimento Celular , Proliferação de Células , Proteínas Ativadoras de GTPase/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Invasividade Neoplásica , Células Tumorais CultivadasRESUMO
Hypoxia is the most common microenvironment feature of lung cancer tumors, which affects cancer progression, metastasis and metabolism. Oxygen induces both proteomic and genomic changes within tumor cells, which cause many alternations in the tumor microenvironment (TME). This review defines current knowledge in the field of tumor hypoxia in non-small cell lung cancer (NSCLC), including biology, biomarkers, in vitro and in vivo studies and also hypoxia imaging and detection. While classic two-dimensional (2D) in vitro research models reveal some hypoxia dependent manifestations, three-dimensional (3D) cell culture models more accurately replicate the hypoxic TME. In this study, a systematic review of the current NSCLC 3D models that have been able to mimic the hypoxic TME is presented. The multicellular tumor spheroid, organoids, scaffolds, microfluidic devices and 3D bioprinting currently being utilized in NSCLC hypoxia studies are reviewed. Additionally, the utilization of 3D in vitro models for exploring biological and therapeutic parameters in the future is described.
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Carcinoma Pulmonar de Células não Pequenas/patologia , Imageamento Tridimensional , Neoplasias Pulmonares/patologia , Modelos Biológicos , Hipóxia Tumoral , Bioimpressão , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Neoplasias Pulmonares/genéticaRESUMO
Sézary syndrome (SS) is an aggressive form of cutaneous T-cell lymphoma (CTCL) characterized by the presence of circulating malignant CD4+ T cells (Sézary cells) with many complex changes in the genome, transcriptome and epigenome. Epigenetic dysregulation seems to have an important role in the development and progression of SS as it was shown that SS cells are characterized by widespread changes in DNA methylation. In this study, we show that the transmembrane protein coding gene TMEM244 is ectopically expressed in all SS patients and SS-derived cell lines and, to a lower extent, in mycosis fungoides and in a fraction of T-cell lymphomas, but not in B-cell malignancies and mononuclear cells of healthy individuals. We show that in patient samples and in the T-cell lines TMEM244 expression is negatively correlated with the methylation level of its promoter. Furthermore, we demonstrate that TMEM244 expression can be activated in vitro by the CRISPR-dCas9-induced specific demethylation of TMEM244 promoter region. Since both, TMEM244 expression and its promoter demethylation, are not detected in normal lymphoid cells, they can be potentially used as markers in Sézary syndrome and some other T-cell lymphomas.
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Metilação de DNA , Regulação da Expressão Gênica/genética , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas/genética , Síndrome de Sézary/genética , Idoso , Idoso de 80 Anos ou mais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Feminino , Vetores Genéticos , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Humanos , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/metabolismo , Masculino , Proteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Micose Fungoide/genética , Micose Fungoide/metabolismo , Proteínas de Neoplasias/biossíntese , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Síndrome de Sézary/metabolismoRESUMO
AIMS: Type 1 diabetes (T1D) is an autoimmune disorder caused by the T-cell mediated destruction of the insulin-producing pancreatic beta cells. T1D is a consequence of complex processes, influenced by genetic, epigenetic and environmental factors. MicroRNAs (miRNAs) are small non-coding RNAs that target multiple mRNAs and regulate gene expression. The implication of miRNAs in T1D pathogenesis, as potential modulators of immune response genes, remains poorly defined. The aim of this study was to investigate the expression profile of miRNAs in new onset T1D and the impact of deregulated miRNAs on target genes. METHODS: Total RNA from peripheral blood mononuclear cells of newly diagnosed T1D pediatric patients and age-matched controls was screened for disease-associated miRNAs by a microarray analysis, with subsequent validation by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). miRNA targets were identified by luciferase reporter assays. RESULTS: The microarray analysis revealed 91 deregulated miRNAs (Pâ¯<â¯0.05) in T1D group compared to non-diabetic controls. Within this group we observed one upregulated and seven downregulated miRNAs with fold change >2.0. qRT-PCR validation revealed overexpression of miR-487a-3p which has not been previously reported in the context of T1D. Luciferase reporter assays indicated CTLA4 and FOXO3 genes as miR-487a-3p targets. CONCLUSION: Our study suggests that miR-487a-3p might repress CTLA4 and FOXO3 by binding to their 3'UTRs and contribute to the development of T1D.
Assuntos
Antígeno CTLA-4/genética , Diabetes Mellitus Tipo 1/genética , Proteína Forkhead Box O3/genética , MicroRNAs/genética , Antígeno CTLA-4/metabolismo , Criança , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Feminino , Proteína Forkhead Box O3/metabolismo , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/metabolismo , Regulação para CimaRESUMO
BACKGROUND: DNA damage repair is a complex process, which can trigger the development of cancer if disturbed. In this study, we hypothesize a role of variants in the ATM, H2AFX and MRE11 genes in determining breast cancer (BC) susceptibility. METHODS: We examined the whole sequence of the ATM kinase domain and estimated the frequency of founder mutations in the ATM gene (c.5932G > T, c.6095G > A, and c.7630-2A > C) and single nucleotide polymorphisms (SNPs) in H2AFX (rs643788, rs8551, rs7759, and rs2509049) and MRE11 (rs1061956 and rs2155209) among 315 breast cancer patients and 515 controls. The analysis was performed using high-resolution melting for new variants and the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method for recurrent ATM mutations. H2AFX and MRE11 polymorphisms were analyzed using TaqMan assays. The cumulative genetic risk scores (CGRS) were calculated using unweighted and weighted approaches. RESULTS: We identified four mutations (c.6067G > A, c.8314G > A, c.8187A > T, and c.6095G > A) in the ATM gene in three BC cases and two control subjects. We observed a statistically significant association of H2AFX variants with BC. Risk alleles (the G of rs7759 and the T of rs8551 and rs2509049) were observed more frequently in BC cases compared to the control group, with P values, odds ratios (OR) and 95% confidence intervals (CIs) of 0.0018, 1.47 (1.19 to 1.82); 0.018, 1.33 (1.09 to 1.64); and 0.024, 1.3 (1.06 to 1.59), respectively. Haplotype-based tests identified a significant association of the H2AFX CACT haplotype with BC (P < 0.0001, OR = 27.29, 95% CI 3.56 to 209.5). The risk of BC increased with the growing number of risk alleles. The OR (95% CI) for carriers of ≥ four risk alleles was 1.71 (1.11 to 2.62) for the CGRS. CONCLUSIONS: This study confirms that H2AFX variants are associated with an increased risk of BC. The above-reported sequence variants of MRE11 genes may not constitute a risk factor of breast cancer in the Polish population. The contribution of mutations detected in the ATM gene to the development of breast cancer needs further detailed study.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Variação Genética , Histonas/genética , Adulto , Idoso , Alelos , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Reparo do DNA , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Desequilíbrio de Ligação , Proteína Homóloga a MRE11/genética , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Regiões Promotoras GenéticasRESUMO
Several genome-wide association studies (GWASs), have identified that FAM13A and IREB2 loci are associated with lung cancer, but the mechanisms by which these genes contribute to lung diseases susceptibility, especially in hypoxia context, are unknown. Hypoxia has been identified as a major negative factor for tumor progression in clinical observation. It has been suggested, that lower oxygen tension, may modulate the IREB2 and FAM13A activity. However, the role of these genes in hypoxia response has not been explained. To precise the role of these genes in hypoxia response, we analyzed the FAM13A and IREB2 expression, in lung cancer cells in vitro and lung cancer tissue fragments cultured ex vivo. Three cell lines: non-small cell lung cancer (A549, CORL-105), human lung fibroblasts (HL) and 37 lung cancer tissue fragments were analyzed. The expression of IREB2, FAM13A and HIF1α after sustained 72 hours of hypoxia versus normal oxygen concentration were analyzed by TaqMan® Gene Expression Assays and Western Blot. The expression of FAM13A was significantly up-regulated by hypoxia in two lung cancer cell lines (A549, CORL-105, P<0.001), both at the level of protein and mRNA, and in lung cancer tissue fragments (P=0.0004). The IREB2 was down-regulated after hypoxia in A549 cancer cells (P<0.001). CONCLUSIONS: We found that FAM13A overexpression in human lung cancer cell lines overlapped with hypoxia effect on lung cancer tissues. FAM13A is strongly induced by hypoxia and may be identified as a novel hypoxia-induced gene in non-small cell lung cancer.
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Genome-wide association studies have identified loci at 15q25 (IREB2) and 4q22 (FAM13A), associated with lung cancer (LC) and chronic obstructive pulmonary disease (COPD). The aim of our research was to determine the association of IREB2 and FAM13A SNPs with LC and severe/very severe COPD patients. We examined IREB2 variants (rs2568494, rs2656069, rs10851906, rs13180) and FAM13A (rs1903003, rs7671167, rs2869967) among 1.141 participants (468 LC, 149 COPD, 524 smoking controls). The frequency of the minor IREB2 rs2568494 AA genotype, was higher in LC vs controls (P = 0.0081, OR = 1.682). The FAM13A rs2869967 was associated with COPD (minor CC genotype: P = 0.0007, OR = 2.414). The rs1903003, rs7671167 FAM13A variants confer a protective effect on COPD (both P < 0.002, OR < 0.405). Haplotype-based tests identified an association of the IREB2 AAAT haplotype with LC (P = 0.0021, OR = 1.513) and FAM13A TTC with COPD (P = 0.0013, OR = 1.822). Cumulative genetic risk score analyses (CGRS), derived by adding risk alleles, revealed that the risk for COPD increased with the growing number of the FAM13A risk alleles. OR (95% CI) for carriers of ≥5 risk alleles reached 2.998 (1.8 to 4.97) compared to the controls. This study confirms that the IREB2 variants contribute to an increased risk of LC, whereas FAM13A predisposes to increased susceptibility to COPD.
Assuntos
Proteínas Ativadoras de GTPase/genética , Estudos de Associação Genética , Loci Gênicos , Predisposição Genética para Doença , Proteína 2 Reguladora do Ferro/genética , Neoplasias Pulmonares/genética , Doença Pulmonar Obstrutiva Crônica/genética , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fatores de RiscoRESUMO
The NBN gene, also known as NBS1, is located on the chromosome band 8q21.3, and encodes a 754-amino acid-long protein named nibrin. This protein is a member of the MRE1-RAD50-NBN nuclear complex, and is involved in numerous cell processes essential for maintaining genomic stability. Heterozygous variants in the NBN gene, including p.I171V, c.657del5 and p.R215W, have been described as risk factors for the development of several malignancies. However, there is no report regarding the association of these mutations with lung cancer thus far. Therefore, the present study aimed to evaluate whether there is an association between the heterozygous p.I171V, c.657del5 and p.R215W variants of the NBN gene and the risk of developing lung cancer. The frequency of these variants was estimated in a group of 453 adults diagnosed with non-small cell lung cancer (NSCLC) and in healthy controls (2,400 for p.I171V, 2,090 for c.657del5 and 498 for p.R215W). The p.I171V variant was assessed by restriction fragment length polymorphism analysis of polymerase chain reaction (PCR) products, using MunI (MfeI) restriction enzyme, whereas the c.657del5 and p.R215W variants were assessed by the PCR single-strand conformation polymorphism method. A significantly increased risk of developing lung cancer was observed for the p.I171V variant, which was present in 17 (3.75%) of the 453 cases of lung cancer and in 12 (0.5%) of the 2,400 healthy individuals (odds ratio, 7.759; P<0.0001). The results obtained indicated an association between the p.I171V mutation and the development of lung cancer. Therefore, this variant may be considered a risk factor for NSCLC. Prospective studies with larger groups of patients may reveal the potential impact of the p.I171V variant in the occurrence of lung cancer.
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BACKGROUND: The members of MRE11/RAD50/NBN (MRN) protein complex participates in DNA double-strand break repair and DNA-damage checkpoint activation. We have previously shown that the p.I171V NBN gene mutation may contribute to the development of laryngeal cancer. This study tested the hypothesis that variants of the MRE11 and RAD50 genes, previously described as cancer risk factors, predispose to increased susceptibility to head and neck cancer. FINDINGS: In this study we analyzed the RAD50 and MRE11 genes in 358 patients: 175 with a single laryngeal cancer (LC), 115 with multiple primary tumors but one malignancy (primary or second) localized in the larynx (MPT-LC), 68 patients with multiple primary tumors localized in the head or neck (MPT) and 506 controls. No carriers of previously reported mutation in the MRE11 or RAD50 gene (particularly the pathogenic c.687delT) were detected in the present study. We identified the p.V127I variant (2/175 LC, 2/506 controls; OR=2.91; 95% CI 0.41-20.85) and p.V315L variant (2/115 MPT-LC, 1/506 controls; OR=8.96; 95% CI 0.81-99.68) of the RAD50 gene. CONCLUSIONS: Our data indicated that previously described common genetic variations in the MRE11 and RAD50 genes do not contribute to an increased risk of laryngeal cancer and second primary tumors localized in the head and neck. Prospective studies with larger groups of patients may reveal the possible impact of these genes in tumor occurrence.
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Carcinoma de Células Escamosas/genética , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Neoplasias Laríngeas/genética , Hidrolases Anidrido Ácido , Estudos de Casos e Controles , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Heterozigoto , Humanos , Proteína Homóloga a MRE11 , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: The MRE11, RAD50, and NBN genes encode proteins of the MRE11-RAD50-NBN (MRN) complex involved in cellular response to DNA damage and the maintenance of genome stability. In our previous study we showed that the germline p.I171V mutation in NBN may be considered as a risk factor in the development of childhood acute lymphoblastic leukemia (ALL) and some specific haplotypes of that gene may be associated with childhood leukemia. These findings raise important questions about the role of mutations in others genes of the MRN complex in childhood leukemia. The aim of this study was to answer the question whether MRE11 and RAD50 alterations may be associated with childhood ALL or AML. METHODS: We estimated the frequency of constitutional mutations and polymorphisms in selected regions of MRE11, RAD50, and NBN in the group of 220 children diagnosed with childhood leukemias and controls (n=504/2200). The analysis was performed by specific amplification of region of interest by PCR and followed by multi-temperature single-strand conformation polymorphism (PCR-MSSCP) technique. We performed two molecular tests to examine any potential function of the detected the c.551+19G>A SNP in RAD50 gene. To our knowledge, this is the first analysis of the MRE11, RAD50 and NBN genes in childhood leukemia. RESULTS: The frequency of either the AA genotype or A allele of RAD50_rs17166050 were significantly different in controls compared to leukemia group (ALL+AML) (p<0.0019 and p<0.0019, respectively). The cDNA analysis of AA or GA genotypes carriers has not revealed evidence of splicing abnormality of RAD50 pre-mRNA. We measured the allelic-specific expression of G and A alleles at c.551+19G>A and the statistically significant overexpression of the G allele has been observed. Additionally we confirmed the higher incidence of the p.I171V mutation in the leukemia group (7/220) than among controls (12/2400) (p<0.0001). CONCLUSION: The formerly reported sequence variants in the RAD50 and MRE11 gene may not constitute a risk factor of childhood ALL in Polish population. The RAD50_rs17166050 variant allele is linked to decreased ALL risk (p<0.0009, OR=0.6358 (95%CI: 0.4854-0.8327)). Despite the fact that there is no splicing abnormality in carriers of the variant allele but an excess of the G over the A allele was consistently observed. This data demonstrate that some specific alternations of the RAD50 gene may be associated with childhood ALL.
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Proteínas de Ciclo Celular/genética , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Mutação em Linhagem Germinativa , Leucemia/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Hidrolases Anidrido Ácido , Adolescente , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Reparo do DNA , Frequência do Gene , Instabilidade Genômica , Genótipo , Humanos , Lactente , Leucemia/diagnóstico , Proteína Homóloga a MRE11 , Complexos Multiproteicos/genéticaRESUMO
BACKGROUND: We investigated whether genetic polymorphisms of the DNA repair gene NBN are associated with head and neck cancer risk. METHODS: We analyzed 6 polymorphisms in 175 patients with a single laryngeal tumor, 104 with multiple primary tumors but 1 malignancy (primary/second) localized in the larynx, 60 patients with multiple primary tumors localized in the head or neck, and 275 controls. RESULTS: Although frequencies of single nucleotide polymorphism alleles did not show marked differences, we found significant differences in haplotype frequencies between patients and controls. Haplotypes GGTTAA and ACCCGT were associated with an increased risk of laryngeal cancer (p < .0001, p = .002) and haplotypes GGCCAA and GCCCGT with an increased risk of multiple primary tumors (p < .0001, p = .039). CONCLUSION: Specific haplotypes of the NBN gene may be related to increased susceptibility to laryngeal cancer and second primary tumors localized in the head and neck.
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Proteínas de Ciclo Celular/genética , Haplótipos/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias Laríngeas/genética , Neoplasias Primárias Múltiplas/genética , Proteínas Nucleares/genética , Polimorfismo Genético , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologiaAssuntos
Neoplasias da Mama/genética , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Mutação , Hidrolases Anidrido Ácido , Neoplasias da Mama/etnologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Humanos , Razão de Chances , Polônia , Medição de Risco , Fatores de RiscoRESUMO
Several lines of evidence indicate that retinoids, derivates of vitamin A, affect reproductive function in birds, however, the mechanism of their action in the ovary is still unknown. Therefore, the present study was designed (i) to show whether in the domestic hen 9-cis retinoic acid (9-cis RA), one of the retinoids, influences steroid secretion in vitro by white and yellow chicken ovarian follicles, and (ii) to detect expression of retinoic acid RXR receptor mRNA in these follicles. The white follicles (small: 1-4 mm, medium: 4-6 mm and large 6-8 mm in diameter) and the three largest yellow preovulatory follicles (F3-F1; 25-37 mm) were isolated from the ovary 3 h before ovulation. The granulosa layer was separated from the theca layer in the preovulatory follicles, which were subsequently divided into 4 equal pieces. The isolated whole white follicles or parts of the granulosa or theca layers were incubated for 24 h at 38 degrees C in Eagle's medium in the following 4 groups: control, ovine LH (oLH; 10 ng/ml), 9-cis RA (100 ng/ml) and 9-cis RA + oLH. After incubation, the medium was collected for estradiol (E2) and progesterone (P4) determination while tissues were saved for protein assay. It was found that 9-cis RA affects steroid secretion from chicken ovarian follicles. It decreased E2 secretion from white follicles and from the theca layer of the two largest (F2 and F1) preovulatory follicles. 9-cis RA had no effect on oLH-stimulated E2 secretion by the white follicles and yellow F2 and F1 follicles, but it diminished E2 secretion by F3 follicles. As regards P4, the effect of 9-cis RA was opposite; it increased P4 secretion from the granulosa layer of all preovulatory follicles. 9-cis RA did not change oLH-stimulated P4 secretion by granulosa layers ofF3 and F2 follicles, however, it inhibited oLH-enhanced P4 secretion from the F1 granulosa layer. In a separate experiment, the presence of mRNA encoding RXR was found in the stroma and all follicles of the chicken ovary by means of the RT-PCR technique. The results indicate that retinoids, acting by specific nuclear receptors, are modulators of follicular steroidogenesis in the chicken ovary.