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1.
J Chem Phys ; 151(12): 125101, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31575173

RESUMO

Gene regulation is one of the most important fundamental biological processes in living cells. It involves multiple protein molecules that locate specific sites on DNA and assemble gene initiation or gene repression multimolecular complexes. While the protein search dynamics for DNA targets has been intensively investigated, the role of intermolecular interactions during the genetic activation or repression remains not well quantified. Here, we present a simple one-dimensional model of target search for two interacting molecules that can reversibly form a dimer molecular complex, which also participates in the search process. In addition, the proteins have finite residence times on specific target sites, and the gene is activated or repressed when both proteins are simultaneously present at the target. The model is analyzed using first-passage analytical calculations and Monte Carlo computer simulations. It is shown that the search dynamics exhibit a complex behavior depending on the strength of intermolecular interactions and on the target residence times. We also found that the search time shows a nonmonotonic behavior as a function of the dissociation rate for the molecular complex. Physical-chemical arguments to explain these observations are presented. Our theoretical approach highlights the importance of molecular interactions in the complex process of gene activation/repression by multiple transcription factor proteins.


Assuntos
DNA/química , Modelos Químicos , Simulação por Computador , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Cinética , Método de Monte Carlo , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
2.
Adv Exp Med Biol ; 1152: 9-29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456177

RESUMO

Epidemiologic studies have contributed importantly to current knowledge of environmental and genetic risk factors for breast cancer. Worldwide, breast cancer is an important cause of human suffering and premature mortality among women. In the United States, breast cancer accounts for more cancer deaths in women than any site other than lung cancer. A variety of risk factors for breast cancer have been well-established by epidemiologic studies including race, ethnicity, family history of cancer, and genetic traits, as well as modifiable exposures such as increased alcohol consumption, physical inactivity, exogenous hormones, and certain female reproductive factors. Younger age at menarche, parity, and older age at first full-term pregnancy may influence breast cancer risk through long-term effects on sex hormone levels or by other biological mechanisms. Recent studies have suggested that triple negative breast cancers may have a distinct etiology. Genetic variants and mutations in genes that code for proteins having a role in DNA repair pathways and the homologous recombination of DNA double stranded breaks (APEX1, BRCA1, BRCA2, XRCC2, XRCC3, ATM, CHEK2, PALB2, RAD51, XPD), have been implicated in some cases of breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Ligação a DNA/genética , Feminino , Predisposição Genética para Doença , Recombinação Homóloga , Humanos , Mutação , Gravidez , Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/etiologia
3.
J Cancer Res Clin Oncol ; 145(9): 2273-2283, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31428934

RESUMO

OBJECTIVES: Recent research has classified lung adenocarcinoma patients with KRAS mutation into three subtypes by co-occurring genetic events in TP53 (KP subgroup), STK11/LKB1 (KL subgroup) and CDKN2A/B inactivation plus TTF-1 low expression (KC subgroup). The aim of this study was to identify valuable biomarkers by searching the candidate molecules that contribute to lung adenocarcinoma pathogenesis, especially KC subtype. MATERIALS AND METHODS: We analyzed the publicly available database and identified the candidate REG4 using the E-GEOD-31210 dataset, and then confirmed by TCGA dataset. In addition, an independent cohort of 55 clinical samples was analyzed by quantitative real-time PCR analysis. Functional studies and RNA sequencing were performed after silencing the REG4 expression. RESULTS: REG4, an important regulator of gastro-intestinal carcinogenesis, was highly expressed in KRAS mutant lung adenocarcinoma with low expression of TTF-1 (KC subtype). The results were validated both by gene expression analysis and immunohistochemistry study in an independent 55 clinical samples from Fudan University Shanghai Cancer Center. Further in vitro and in vivo functional assays revealed silencing REG4 expression significantly reduces cancer cell proliferation and tumorigenesis. Moreover, RNA sequencing and GSEA analysis displayed that REG4 knockdown might induce cell cycle arrest by regulating G2/M checkpoint and E2F targets. CONCLUSION: Our results indicate that REG4 plays an important role in KRAS-driven lung cancer pathogenesis and is a novel biomarker of lung adenocarcinoma subtype. Future studies are required to clarify the underlying mechanisms of REG4 in the division and proliferation of KC tumors and its potential therapeutic value.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico , Biomarcadores Tumorais/genética , Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/genética , Neoplasias Pulmonares/diagnóstico , Proteínas Associadas a Pancreatite/genética , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Fatores de Transcrição/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Estudos de Coortes , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Mutantes/genética , Proteínas Mutantes/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Transcrição/metabolismo
4.
Anticancer Res ; 39(8): 4129-4136, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366497

RESUMO

BACKGROUND/AIM: 5-Aza-2-deoxycytidine (5-Aza-CdR) enhances the sensitivity to 5-fluorouracil (5-FU), but the molecular mechanism is not fully understood. The aim of this study was to investigate the molecular mechanism that enhances the sensitivity to 5-FU treated with 5-Aza-CdR via thymidine phosphorylase (TP). MATERIALS AND METHODS: The sensitivity to drugs was determined on several cancer cell lines by the MTT assay. Protein and mRNA levels were examined by immunoblot and RT-PCR, respectively. Gene silencing, binding of Sp1 to DNA and methylation of DNA was performed by siRNA, ChIP assay and sodium bisulfate genomic sequencing, respectively. RESULTS: Sp1-binding sites in the TP promoter were methylated in epidermoid carcinoma. 5-Aza-CdR demethylated Sp1-binding sites and enhanced sensitivity to 5-FU. CONCLUSION: Demethylation of Sp1-binding sites by 5-Aza-CdR was a key factor enhancing 5-FU sensitivity, which may enable more effective treatments for cancer patients with the combination of 5-Aza-CdR and 5-FU.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Metilação de DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Transcrição Sp1/genética , Timidina Fosforilase/genética , Sítios de Ligação/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Decitabina/metabolismo , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/genética , Timidina Fosforilase/química
5.
Anticancer Res ; 39(8): 4149-4164, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366500

RESUMO

BACKGROUND/AIM: Signaling regulation of myeloid zinc finger 1 (MZF1) has been implicated in the progression of many human malignancies; however, the mechanistic action of MZF1 in triple-negative breast cancer (TNBC) progression remains elusive. In this study, the aim was to investigate the molecular mechanisms of MZF1 and its functional role in TNBC cellular migration and invasion. MATERIALS AND METHODS: Hs578T and MDA-MB-231 cells were transfected to stably express the acidic domain of MZF1 (MZF160-72), or were transfected with MZF1-specific or ELK1-specific short hairpin RNA (shRNA). Changes in cell morphology and distributions of cellular proteins were observed and subsequently migration and invasion were measured by wound healing and transwell assays. Expression levels of epithelial-mesenchymal transition (EMT)-related genes were carried out using immunoblotting and quantitative reverse transcription-polymerase chain reaction (RT-PCR) assays. Data of transcriptional regulation were obtained from promoter-luciferase reporter and chromatin immunoprecipitation (ChIP) assays. RESULTS: Herein, we found that MZF1 in high-level MZF1-expressing TNBC cells is associated with cell migration, invasion, and mesenchymal phenotype. MZF1 interacted with the promoter region of insulin-like growth factor 1 receptor (IGF1R) to drive invasion and metastasis of high-level MZF1-expressing TNBC cells. Exogenous expression of the acidic domain of MZF1 repressed the binding of endogenous MZF1 to IGF1R promoter via blocking the interaction with ETS-like gene 1 (ELK1). This blockage not only caused MZF1 protein degradation, but also restrained ELK1 nuclear localization in high-level MZF1-expressing TNBC cells. MZF1, but not ELK1, was necessary for the retention of mesenchymal phenotype by repressing IGF1R promoter activity in TNBC cells expressing high levels of MZF1. Activation of the IGF1R-driven p38MAPK-ERα-slug-E-cadherin signaling axis mediated the conversion of mesenchymal cell to epithelial phenotype, caused by MZF1 destabilization. These results suggest that MZF1 is an oncogenic inducer. CONCLUSION: Blocking of the MZF1/ELK1 interaction to reduce MZF1 protein stability by saturating the endogenous MZF1/ELK1 binding domains might be a promising therapeutic strategy for the treatment of high-level MZF1-expressing TNBC.


Assuntos
Fatores de Transcrição Kruppel-Like/genética , Receptores de Somatomedina/genética , Neoplasias de Mama Triplo Negativas/genética , Proteínas Elk-1 do Domínio ets/genética , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proteínas de Ligação a DNA/genética , Transição Epitelial-Mesenquimal/genética , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Regiões Promotoras Genéticas/genética , Domínios Proteicos/genética , Transdução de Sinais/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética
6.
Artigo em Chinês | MEDLINE | ID: mdl-31446696

RESUMO

Objective:To make the molecular diagnosis of a patient complaining hearing loss and with specific facial features, developmental delay, vertebral dysplasia, hypotonia and other suspected phenotypes of Kabuki make-up syndrome(KS); to investigate the characteristics and main phenotypes of KS. Method:①Whole-exome sequencing and bioinformatics analysis were performed for proband and her parents. ②Literatures describing the clinical features of KS patients with clear molecular diagnosis from the period of Aug 2010 to Mar 2019 were collected from databases of PubMed and CNKI. Result:①The proband carries the c. 15777insT variant(p. Pro5260fs*10) in KMT2D gene. The variant causes the termination codon to appear prematurely. KMT2D c. 15777insT was classified as PVS1+PS1+PM2 according to the ACMG variation interpretation standard, which is a disease-causing mutation. The c. 15777insT was first reported as a pathogenic mutation of KS. ②77 peer-reviewed publications on KS were analysed including 462 patients with KS. The main findings were intellectual disability(305 cases), congenital heart defects(227 cases), hypotonia(184 cases), short fingers(147 cases), short stature(144 cases), cleft palate(139 cases), hearing loss(101 cases) and developmental delay(99 cases). Of the 101 patients with hearing loss, 11 were confirmed to have conductive hearing loss(1 with recurrent otitis media), 3 with mixed hearing loss, 12 with sensorineural deafness(1 with recurrence otitis media) and 75 patients with unidentified types of deafness(28 with recurrent otitis media). Conclusion:KS involves defects of a wide range of organs, with each organ showing different severity of symptoms, which is easily misdiagnosed from the phenotypes. We suggest the diagnosis on hearing loss in KS patients should be strengthened. KMT2D and KDM6A are two pathogenic genes that have been identified for KS. With the increase of age, its typical clinical phenotypes become more and more obvious. When there is only atypical suspected KS symptoms in the early neonatal period, relevant genetic test should be performed as soon as possible to achieve early diagnosis and intervention.


Assuntos
Anormalidades Múltiplas/genética , Proteínas de Ligação a DNA/genética , Face/anormalidades , Perda Auditiva/etiologia , Doenças Hematológicas/complicações , Doenças Hematológicas/genética , Proteínas de Neoplasias/genética , Doenças Vestibulares/complicações , Doenças Vestibulares/genética , Feminino , Humanos , Mutação , Fenótipo
7.
Medicine (Baltimore) ; 98(32): e16541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393355

RESUMO

BACKGROUNDS: Previous investigations yielded inconsistent results for the associations between pancreatic cancer (PC) risk and genetic polymorphisms. The study aimed to perform a systematic review and meta-analysis of studies exploring association of some genetic polymorphisms and PC risk. METHODS: We systematically searched on PubMed and Web of Science for association of genetic polymorphisms and PC risk published from 1969 to January 2019. We computed the multivariate odd ratio (OR) and 95% confidence intervals (CI), comparing different genetic types. RESULTS: The present meta-analysis showed significant associations between deoxyribonucleic acid (DNA) repair gene (X-ray repair cross-complementing group 1 (XRCC1) Arg399GIn and Arg194Trp, excision repair cross complementation 1 (ERCC1) rs11615 and rs3212986, ERCC2 rs13181) polymorphisms and PC risk. CONCLUSIONS: Because of the limited sample size and ethnicity enrolled in the present meta-analysis, further larger scaled studies should be performed to demonstrate the association.


Assuntos
Neoplasias Pancreáticas/genética , DNA Glicosilases/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética
8.
Gene ; 715: 144015, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31357025

RESUMO

Tripartite Motif Containing 13 (TRIM13), a member of TRIM proteins, is deleted in multiple tumor types, especially in B-cell chronic lymphocytic leukemia and multiple myeloma. The present study explored the expression and potential role of TRIM13 in non-small-cell lung carcinoma (NSCLC). We found that TRIM13 mRNA and protein expression was reduced in NSCLC tissues and cell lines in comparison to paired non-cancerous tissues and a human normal bronchial epithelial cell line, respectively. Overexpression of TRIM13 in NCI-H1975 and SPC-A-1 cells hampered cell proliferation. Additionally, TRIM13 overexpression increased the levels of cleaved caspase-3. TRIM13-induced NSCLC cell apoptosis was attenuated by a caspase-3 inhibitor Ac-DEVD-CHO, suggesting that TRIM13 induced cell apoptosis partially through a caspase-3-dependent pathway. Moreover, it has been reported that TRIM13 can regulate nuclear factor kappaB (NF-κB) activity. Our data showed that TRIM13 overexpression inactivated NF-κB as indicated by the increased cytosolic NF-κB and decreased nuclear NF-κB. Exposure to an NF-κB inhibitor PDTC significantly blocked the impact of TRIM13 knockdown on cell proliferation and apoptosis, indicating the functions of TRIM13 in NSCLC cells were mediated by the NF-κB pathway. Finally, we demonstrated that TRIM13 overexpression suppressed tumor growth and induced cell apoptosis in vivo by using a xenograft mouse model. Collectively, our results indicate that TRIM13 behaves as a tumor suppressor in NSCLC through regulating NF-κB pathway. Our findings may offer a promising therapeutic target for NSCLC.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Células A549 , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Ligação a DNA/genética , Feminino , Xenoenxertos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , NF-kappa B/genética , Transplante de Neoplasias , Transdução de Sinais , Proteínas Supressoras de Tumor/genética
9.
Gene ; 714: 143985, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31330236

RESUMO

In all eukaryotes, the response to heat stress (HS) is dependent on the activity of HS transcription factors (Hsfs). Plants contain a large number of Hsfs, however, only members of the HsfA1 subfamily are considered as master regulators of stress response and thermotolerance. In Solanum lycopersicum, among the four HsfA1 members, only HsfA1a has been proposed to possess a master regulator function. We performed a comparative analysis of HsfA1a, HsfA1b, HsfA1c and HsfA1e at different levels of regulation and function. HsfA1a is constitutively expressed under control and stress conditions, while the other members are induced in specific tissues and stages of HS response. Despite that all members are localized in the nucleus when expressed in protoplasts, only HsfA1a shows a wide range of basal activity on several HS-induced genes. In contrast, HsfA1b, HsfA1c, and HsfA1e show only high activity for specific subsets of genes. Domain swapping mutants between HsfA1a and HsfA1c revealed that the variation in that transcriptional transactivation activity is due to differences in the DNA binding domain (DBD). Specifically, we identified a conserved arginine (R107) residue in the turn of ß3 and ß4 sheet in the C-terminus of the DBD of HsfA1a that is highly conserved in plant HsfA1 proteins, but is replaced by leucine and cysteine in tomato HsfA1c and HsfA1e, respectively. Although not directly involved in DNA interaction, R107 contributes to DNA binding and consequently the activity of HsfA1a. Thus, we demonstrate that this variation in DBD in part explains the functional diversification of tomato HsfA1 members.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição de Choque Térmico/genética , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Temperatura Alta , Domínios Proteicos/genética , Protoplastos/fisiologia , Temperatura Ambiente , Termotolerância/genética , Transcrição Genética/genética , Ativação Transcricional/genética
10.
Nat Commun ; 10(1): 2936, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270323

RESUMO

ß-Arrestins are major regulators of G protein-coupled receptor-mediated signaling processes. Their potential roles in regulating adipocyte function in vivo remain unexplored. Here we report the novel finding that mice lacking ß-arrestin-2 (barr2) selectively in adipocytes show significantly reduced adiposity and striking metabolic improvements when consuming excess calories. We demonstrate that these beneficial metabolic effects are due to enhanced signaling through adipocyte ß3-adrenergic receptors (ß3-ARs), indicating that barr2 represents a potent negative regulator of adipocyte ß3-AR activity in vivo. Interestingly, essentially all beneficial metabolic effects caused by adipocyte barr2 deficiency are absent in adipocyte barr2-PRDM16 double KO mice, indicating that the metabolic improvements caused by the lack of barr2 in adipocytes are mediated by the browning/beiging of white adipose tissue. Our data support the novel concept that 'G protein-biased' ß3-AR agonists that do not promote ß3-AR/barr2 interactions may prove useful for the treatment of obesity and related metabolic disorders.


Assuntos
Adipócitos/metabolismo , Metabolismo Energético , Glucose/metabolismo , beta-Arrestina 2/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Homeostase , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Adrenérgicos beta 3/genética , Receptores Adrenérgicos beta 3/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , beta-Arrestina 2/genética
11.
Cancer Sci ; 110(9): 2760-2772, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31325400

RESUMO

Long noncoding RNAs (lncRNAs) are emerging as key regulators in cancer initiation and progression. TP53TG1 is a recently identified lncRNA and several studies have shown that TP53TG1 may play the role of tumor suppressor gene or oncogene in different tumors. Nevertheless, the involvement of TP53TG1 in carcinogenesis of pancreatic ductal adenocarcinoma (PDAC) has not been characterized. In our studies, we identified that TP53TG1 was highly expressed in PDAC and was a novel regulator of PDAC development. Knockdown of TP53TG1 inhibited proliferation, induced apoptosis, and decreased migration and invasion in PDAC cells, whereas enhanced expression of TP53TG1 had the opposite effects. Mechanistically, TP53TG1 could directly bind to microRNA (miR)-96 and effectively function as a sponge for miR-96, thus antagonizing the functions of miR-96 and leading to derepression of its endogenous target KRAS, which is a core oncogene in the initiation and maintenance of PDAC. Taken together, these observations imply that TP53TG1 contributes to the growth and progression of PDAC by acting as a competing endogenous RNA (ceRNA) to competitively bind to miR-96 and regulate KRAS expression, which highlights the importance of the complicated miRNA-lncRNA network in modulating the progression of PDAC.


Assuntos
Carcinoma Ductal Pancreático/genética , Proteínas de Ligação a DNA/metabolismo , MicroRNAs/antagonistas & inibidores , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA Longo não Codificante/metabolismo , Carcinogênese/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , RNA Longo não Codificante/genética
12.
Life Sci ; 232: 116679, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31340168

RESUMO

AIMS: Amplified in liver cancer 1 gene (ALC1), a recently identified oncogene, was reported to be overexpressed in esophageal cancer cell lines and identified as a target oncogene in esophageal cancer pathogenesis. However, little literature is available to illustrate its significance in cisplatin resistance of esophageal squamous cell carcinoma (ESCC) cells. The aim of the current study was to investigate the effect of ALC1 on cisplatin cytotoxicity of ESCC cells and to study the potential mechanisms. MAIN METHODS: ALC1 at mRNA and protein levels were detected by qRT-PCR and western blot, respectively. Cell viability was evaluated using CCK-8 assay. Apoptosis was assessed using caspase-3/7 activity assay and flow cytometry analysis. Glycolysis level was evaluated by measuring glucose consumption and lactate production. The protein levels of p-protein kinase B (Akt) and Akt were determined by western blot. KEY FINDINGS: ALC1 was highly expressed in ESCC cells compared with human normal esophageal epithelial Het-1A cells. ALC1 knockdown suppressed the viability, induced apoptosis and enhanced cisplatin cytotoxicity in ESCC cells. In addition, ALC1 knockdown inhibited glycolysis and inactivated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway in ESCC cells. Mechanistically, activation of the PI3K/Akt pathway by 740Y-P blocked the effects of ALC1 knockdown on cisplatin cytotoxicity and glycolysis in ESCC cells. In contrast, inhibition of the PI3K/Akt pathway by LY294002 or glycolysis by 2-deoxyglucose resisted the effect of ALC1 overexpression on cisplatin cytotoxicity in ESCC cells. SIGNIFICANCE: ALC1 knockdown enhanced cisplatin cytotoxicity of ESCC cells by inhibition of glycolysis through inactivation of the PI3K/Akt pathway.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/patologia , Cisplatino/farmacologia , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Neoplasias Esofágicas/patologia , Técnicas de Silenciamento de Genes , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/metabolismo , Ativação Enzimática , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/metabolismo , Glicólise , Humanos , Células Tumorais Cultivadas
13.
Anticancer Res ; 39(6): 3269-3272, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31177178

RESUMO

BACKGROUND/AIM: Although genetic factors are presumed to account only for a part of the inter-individual variation in lung cancer susceptibility, the results are conflicting and there are no data available regarding the Polish population. We, therefore, performed a case-control study to investigate the association of seven selected single nucleotide polymorphisms (SNPs), in genes coding for excision repair cross-complimentary group 1 (ERCC1: rs11615, rs3212986, rs2298881), nuclear factor ĸB (NFKB2: rs7897947, rs12769316), bone morphogenetic protein 4 (BMP4: rs1957860), complement receptor 1 (CR1: rs7525160) and del/ins polymorphism in the family hypoxia inducible factor 2 gene (EGLN2: rs10680577), with non-small cell lung cancer (NSCLC) risk. MATERIALS AND METHODS: Real-time PCR with melting curve analysis was used for genotyping of NSCLC patients and healthy individuals of Polish origin. RESULTS: The ERCC1 rs11615 T allele and rs3212986 GG homozygosity were found to be associated with a higher risk of developing NSCLC. In addition, NFKB2 rs12769316 GG homozygosity was more frequently detected among male patients than controls, while no significant differences were found between the five polymorphisms. CONCLUSION: ERCC1 polymorphisms may affect NSCLC risk in the Polish population, while the NFKB2 variant may be a possible marker of the disease in males.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Neoplasias Pulmonares/genética , Subunidade p52 de NF-kappa B/genética , Polimorfismo de Nucleotídeo Único , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Homozigoto , Humanos , Neoplasias Pulmonares/patologia , Masculino , Fenótipo , Polônia , Fatores de Risco
14.
Nat Commun ; 10(1): 2410, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160587

RESUMO

Medulloblastoma, which is the most common malignant paediatric brain tumour, has a 70% survival rate, but standard treatments often lead to devastating life-long side effects and recurrence is fatal. One of the emerging strategies in the search for treatments is to determine the roles of tumour microenvironment cells in the growth and maintenance of tumours. The most attractive target is tumour-associated macrophages (TAMs), which are abundantly present in the Sonic Hedgehog (SHH) subgroup of medulloblastoma. Here, we report an unexpected beneficial role of TAMs in SHH medulloblastoma. In human patients, decreased macrophage number is correlated with significantly poorer outcome. We confirm macrophage anti-tumoural behaviour in both ex vivo and in vivo murine models of SHH medulloblastoma. Taken together, our findings suggest that macrophages play a positive role by impairing tumour growth in medulloblastoma, in contrast to the pro-tumoural role played by TAMs in glioblastoma, another common brain tumour.


Assuntos
Neoplasias Cerebelares/imunologia , Macrófagos/imunologia , Meduloblastoma/imunologia , Microambiente Tumoral/imunologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Quimiocina CCL2/imunologia , Quimiocina CCL2/metabolismo , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Proteínas Hedgehog/metabolismo , Humanos , Macrófagos/metabolismo , Meduloblastoma/genética , Meduloblastoma/metabolismo , Camundongos , Microglia/imunologia , Células Mieloides/imunologia , Receptores CCR2/genética , Regulação para Cima
15.
Nat Commun ; 10(1): 2757, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227697

RESUMO

Inappropriate expansion of the adipose cells in the subcutaneous adipose tissue (SAT) is a characteristic of hypertrophic obesity and of individuals with genetic predisposition for T2D (first-degree relatives; FDR). It is associated with insulin resistance, a dysfunctional, adipose tissue and reduced adipogenesis. We examined the regulation of adipogenesis in human SAT precursor cells and found ZNF521 to be a critical regulator of early adipogenic commitment and precursor cells leaving the cell cycle. However, neither altered upstream signalling nor lack of SAT progenitor cells could explain the reduced adipogenesis in hypertrophic obesity. Instead, we show that progenitor cells undergoing poor differentiation are characterized by senescence, inability to suppress p53/P16INK4 and secretion of factors reducing adipogenesis in non-senescent cells. We found aging, FDR and established T2D to be associated with increased progenitor cell senescence, reduced adipogenesis and hypertrophic expansion of the SAT adipose cells.


Assuntos
Adipogenia , Senescência Celular/fisiologia , Proteínas de Ligação a DNA/metabolismo , Obesidade/patologia , Gordura Subcutânea/patologia , Adipócitos , Adulto , Idoso , Envelhecimento/fisiologia , Biópsia por Agulha , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Proteínas de Ligação a DNA/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Feminino , Predisposição Genética para Doença , Humanos , Hipertrofia/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/etiologia , Cultura Primária de Células , Transdução de Sinais/fisiologia , Células-Tronco/fisiologia , Gordura Subcutânea/citologia , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
16.
Environ Pollut ; 251: 871-878, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31234252

RESUMO

Di(2-ethylhexyl)phthalate (DEHP) is an ubiquitous and emerging contaminant that is widely present in food, agricultural crop, and the environment, posing a potential risk to human health. This study utilized the nematode Caenorhabditis elegans to decipher the toxic effects of early life exposure to DEHP on aging and its underlying mechanisms. The results showed that exposure to DEHP at 0.1 and 1.5 mg/L inhibited locomotive behaviors. In addition, DEHP exposure significantly shortened the mean lifespan of the worms and further adversely affected pharyngeal pumping rate and defecation cycle in aged worms. Moreover, DEHP exposure also further enhanced accumulation of age-related biomarkers including lipofuscin, lipid peroxidation, and intracellular reactive oxygen species in aged worms. In addition, exposure to DEHP significantly suppressed gene expression of hsp-16.1, hsp-16.49, and hsp-70 in aged worms. Further evidences showed that mutation of genes involved in insulin/IGF-1-like signaling (IIS) pathway (daf-2, age-1, pdk-1, akt-1, akt-2, and daf-16) restored lipid peroxidation accumulation upon DEHP exposure in aged worms, whereas skn-1 mutation resulted in enhanced lipid peroxidation accumulation. Therefore, IIS and SKN-1 may serve as an important molecular basis for DEHP-induced age-related declines in C. elegans. Since IIS and SKN-1 are highly conserved among species, the age-related declines caused by DEHP exposure may not be exclusive in C. elegans, leading to adverse human health consequences due to widespread and persistent DEHP contamination in the environment.


Assuntos
Envelhecimento/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Dietilexilftalato/toxicidade , Poluentes Ambientais/toxicidade , Fator de Crescimento Insulin-Like I/metabolismo , Longevidade/efeitos dos fármacos , Plastificantes/toxicidade , Animais , Biomarcadores/metabolismo , Proteínas de Caenorhabditis elegans/biossíntese , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Choque Térmico/biossíntese , Insulina/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipofuscina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética
17.
Nat Commun ; 10(1): 2885, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253769

RESUMO

Nucleotide excision repair (NER) is the major DNA repair pathway that removes UV-induced and bulky DNA lesions. There is currently no structure of NER intermediates, which form around the large multisubunit transcription factor IIH (TFIIH). Here we report the cryo-EM structure of an NER intermediate containing TFIIH and the NER factor XPA. Compared to its transcription conformation, the TFIIH structure is rearranged such that its ATPase subunits XPB and XPD bind double- and single-stranded DNA, consistent with their translocase and helicase activities, respectively. XPA releases the inhibitory kinase module of TFIIH, displaces a 'plug' element from the DNA-binding pore in XPD, and together with the NER factor XPG stimulates XPD activity. Our results explain how TFIIH is switched from a transcription to a repair factor, and provide the basis for a mechanistic analysis of the NER pathway.


Assuntos
Reparo do DNA , Fator de Transcrição TFIIH/metabolismo , Adenosina Trifosfatases , Animais , Linhagem Celular , Clonagem Molecular , Microscopia Crioeletrônica , DNA/química , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Escherichia coli , Regulação da Expressão Gênica , Humanos , Insetos , Modelos Químicos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Recombinantes , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo , Proteína Grupo D do Xeroderma Pigmentoso/genética , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo
18.
Nat Commun ; 10(1): 2860, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253784

RESUMO

Lacking targetable molecular drivers, triple-negative breast cancer (TNBC) is the most clinically challenging subtype of breast cancer. In this study, we reveal that Death Effector Domain-containing DNA-binding protein (DEDD), which is overexpressed in > 60% of TNBCs, drives a mitogen-independent G1/S cell cycle transition through cytoplasm localization. The gain of cytosolic DEDD enhances cyclin D1 expression by interacting with heat shock 71 kDa protein 8 (HSC70). Concurrently, DEDD interacts with Rb family proteins and promotes their proteasome-mediated degradation. DEDD overexpression renders TNBCs vulnerable to cell cycle inhibition. Patients with TNBC have been excluded from CDK 4/6 inhibitor clinical trials due to the perceived high frequency of Rb-loss in TNBCs. Interestingly, our study demonstrated that, irrespective of Rb status, TNBCs with DEDD overexpression exhibit a DEDD-dependent vulnerability to combinatorial treatment with CDK4/6 inhibitor and EGFR inhibitor in vitro and in vivo. Thus, our study provided a rationale for the clinical application of CDK4/6 inhibitor combinatorial regimens for patients with TNBC.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Lapatinib/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/genética , Receptores ErbB/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Receptor ErbB-2/antagonistas & inibidores , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo
19.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(4): 351-356, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31167695

RESUMO

Objective To explore the genome-wide DNA methylation level and the expression of DNA methylation-related enzymes in the villi tissue of patients with unexplained recurrent spontaneous abortion (URSA). Methods The villi samples were obtained from thirty-one URSA patients (URSA group) and thirty pregnancy women who underwent induced abortion (control group). Total DNA methylation was determined by ELISA. Real-time quantitative PCR was used to detect mRNA levels of DNMT1, DNMT3a, DNMT3b, TET1, TET2 and TET3, and Western blot analysis was used to detect protein levels of DNMT1, DNMT2, DNMT3, TET1, TET2 and TET3. Immunohistochemistry was performed to detect the expression and distribution of DNMT1, DNMT3a, DNMT3b, TET1, TET2 and TET3 in villi tissues. Results Methylation level of total DNA in the URSA group was significantly lower than that of the control group. Compared with the control group, mRNA and protein expression levels of DNMT1 and DNMT3b significantly decreased, while TET1 and TET2 significantly increased in the villi of the URSA group. Conclusion The methylation level is reduced in the villi of URSA women, which may be correlated with up-regulated expression of DNMT1 and DNMT3b and down-regulated expression of TET1 and TET2.


Assuntos
Aborto Habitual/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Proteínas de Ligação a DNA/genética , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , Feminino , Humanos , Imuno-Histoquímica , Gravidez , RNA Mensageiro
20.
Microbiol Res ; 223-225: 79-87, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178055

RESUMO

Vibrio parahaemolyticus is a seafood-borne Gram-negative bacteria causing diarrheal diseases in humans world wide. ToxR is a membrane-associated transcriptional factor which plays an important role in acid stress tolerance and regulates the expression of virulence genes including type III secretion system 1 (T3SS1) and type VI secretion system 1 (T6SS1) in V. parahaemolyticus. However, possible mechanisms of ToxR mediating virulence gene expression have not been fully understood. In this study, we demonstrated that ToxR is essential for V. parahaemolyticus to tolerate acid stress by constructing a ToxR deletion mutant (ΔtoxR) and its complemented strain (toxR+). Quantitative PCR showed that the expression of toxR was up regulated under acid stress condition. RNA-seq analysis showed that ompU encoding one of outer membrane proteins was dramatically down regulated in ΔtoxR. Furthermore, the mutation of ompU also led to a significant reduction in tolerating acid stress indicating that ToxR mediated acid stress through regulating ompU expression. RNA-seq results further confirmed that acid stress condition could alter multiple signaling pathways either depending on ToxR (e.g., quorum sensing, fatty acid metabolism) or independent of ToxR (e.g., biosynthesis of secondary metabolites, microbial metabolism in diverse environment, biosynthesis of antibiotics, biosynthesis of amino acids and carbon metabolism pathways). We also for the first time demonstrated that ToxR positively regulated the expression of T6SS2 gene and the interbacteria killing activity. Our study provides comprehensive understanding of signaling pathways which are regulated by both acid stress and ToxR.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação Bacteriana da Expressão Gênica , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Vibrio parahaemolyticus/metabolismo , Adesinas Bacterianas/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Ácidos Graxos/metabolismo , Percepção de Quorum , Metabolismo Secundário , Análise de Sequência de RNA , Deleção de Sequência , Fatores de Transcrição/genética , Transcriptoma , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo VI/genética , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/crescimento & desenvolvimento , Virulência/genética
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