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1.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33762306

RESUMO

High levels of the intermediate filament protein keratin 17 (K17) are associated with poor prognoses for several human carcinomas. Studies in mouse models have shown that K17 expression is positively associated with growth, survival, and inflammation in skin and that lack of K17 delays onset of tumorigenesis. K17 occurs in the nucleus of human and mouse tumor keratinocytes where it impacts chromatin architecture, gene expression, and cell proliferation. We report here that K17 is induced following DNA damage and promotes keratinocyte survival. The presence of nuclear K17 is required at an early stage of the double-stranded break (DSB) arm of the DNA damage and repair (DDR) cascade, consistent with its ability to associate with key DDR effectors, including γ-H2A.X, 53BP1, and DNA-PKcs. Mice lacking K17 or with attenuated K17 nuclear import showed curtailed initiation in a two-step skin carcinogenesis paradigm. The impact of nuclear-localized K17 on DDR and cell survival provides a basis for the link between K17 induction and poor clinical outcomes for several human carcinomas.


Assuntos
Carcinoma/genética , Reparo do DNA , Queratina-17/metabolismo , Queratinas/metabolismo , Neoplasias Experimentais/genética , 9,10-Dimetil-1,2-benzantraceno/administração & dosagem , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Transporte Ativo do Núcleo Celular , Animais , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma/induzido quimicamente , Carcinoma/patologia , Núcleo Celular/metabolismo , Sobrevivência Celular/genética , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Feminino , Técnicas de Inativação de Genes , Células HeLa , Humanos , Microscopia Intravital , Queratina-17/genética , Queratinócitos , Queratinas/genética , Masculino , Camundongos Knockout , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/patologia , Imagem com Lapso de Tempo
2.
Alcohol Clin Exp Res ; 45(1): 79-91, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33222221

RESUMO

BACKGROUND: Alcohol consumption is a risk factor for breast cancer, contributing to up to nearly 23,000 new cases each year. Mechanistic studies show that alcohol increases tumor aggressiveness and metastatic potential, promotes angiogenesis, induces chronic inflammation, and dysregulates RNA polymerase III-related genes. Alcohol has also been shown to affect estrogen signaling in breast cancer, including in our study of the transcriptomic effects of alcohol in breast cancer cells. METHODS: To elucidate mechanisms of action of alcohol in breast cancer, we carried out secondary analyses of our alcohol-responsive transcriptome data using gene ontology and pathway databases and analysis tools and cistromic data analysis of candidate transcription factors which may mediate the transcriptomic alterations. Predicted alcohol-responsive pathways and mechanisms were perturbed and examined experimentally in breast cancer cells. The clinical relevance of identified genes was determined by expression profiles in patient samples and correlation with disease outcomes and alcohol consumption in previously published study cohorts. RESULTS: Gene ontology analysis showed that alcohol alters the expression of many metabolism-related genes, and cistromic data of differentially expressed genes revealed the potential involvement of nuclear factor of activated T cells 3 (NFATC3) in mediating the transcriptomic effects of alcohol. Pathway analysis also predicted regulation of calcium signaling by alcohol in breast cancer cells. Chemical perturbation of this pathway reversed the effect of alcohol on breast cancer cell growth and reduced the elevated cytosolic Ca2+ levels induced by alcohol. Expression levels of alcohol-responsive genes in tumor samples from breast cancer patients are associated with poor disease outcomes. Moreover, expression of some of these genes was altered in breast cancer patients who consumed alcohol previously as compared to those who did not drink. CONCLUSION: Alcohol alters expression of genes that regulate intracellular calcium levels and downstream signaling pathways which drive breast cancer cell proliferation and disease progression.


Assuntos
Neoplasias da Mama/induzido quimicamente , Sinalização do Cálcio/genética , Carcinoma/induzido quimicamente , Etanol/efeitos adversos , Expressão Gênica/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/mortalidade , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Fatores de Transcrição NFATC/metabolismo
3.
Pak J Pharm Sci ; 34(3): 987-993, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34602423

RESUMO

The current study investigated the prospective effect of Silybum marianum L. and Eucalyptus camaldulensis Dehnh extracts against skin cancer. Skin cancer was induced by 7,12-dimethylbenz(a) anthracene (DMBA) in young Balb/c mice. Plant extracts were administered to animals orally, once/day (100mg/kg, 5 days/week) for the 20 weeks. Anticancer activity was examined via tumor progression, where antimutagenic activity was measured using 8-OHdG and sister chromatid exchange (SCE) levels. Eucalyptus camaldulensis Dehnh. leaves extract and Silybum marianum L. leaves extract significantly reduced 8-OHdG in cultured human lymphocytes in a dose-response manner (P<0.05). Similarly, the leave extracts of both plants significantly reduced chromosomal damage as measured by SCE levels (P<0.05). In the skin painting assay, the leave extracts of both plants significantly delayed the onset of tumors compared to DMBA treated group (P<0.05). The Silybum marianum leaves extract significantly reduced tumor incidence (P<0.01) and papilloma frequency (P<0.01) induced by DMBA. The Eucalyptus camaldulensis leaves extract significantly reduced the number of tumors per animal (P<0.05) and incidence of tumors (P<0.001). The in vitro and in vivo findings showed that leaves of Silybum marianum L. and Eucalyptus camaldulensis Dehnh. extracts might be a promising source for anticancer and antimutagenic agents against human cancer.


Assuntos
Antimutagênicos/farmacologia , Carcinoma/induzido quimicamente , Eucalyptus , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Silybum marianum , Neoplasias Cutâneas/induzido quimicamente , Pele/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Carcinógenos/toxicidade , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patologia , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Técnicas In Vitro , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos , Folhas de Planta , Pele/metabolismo , Pele/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Carga Tumoral/efeitos dos fármacos
4.
Mutagenesis ; 35(6): 499-508, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-33400797

RESUMO

The activation of PIK3CA in bladder carcinoma (BlCa) with its recurrent mutations in exon 9 and 20 were well reported. But the association of arsenic on the activation of the pathway is not well elucidated. Therefore, we aimed to analyse the effect of arsenic on the genetic (copy number variation/mutation) and expression profiles of PIK3CA in primary BlCa samples. Infrequent amplification (16%) of the PIK3CA locus was observed, with higher frequency among the arsenic-high (AsH) than arsenic-low (AsL) samples. Frequent (54%) tumour-specific mutations in exon 9 and 20 of PIK3CA were observed in the BlCa samples with prevalent (47%) C>T transition mutations. Exon 9 and 20 harboured 48% and 73% of the total mutations, respectively, with 37% in E542K/E545K and 25% of the mutation in H1047Y/R. Though mutation frequency in AsH and AsL was found to be comparable, we observed some arsenic-specific mutation at c.1633G>A, c.1634A>C (E545K) and c.2985C>T and c.3130G>T mutations, as well as prevalent transverse mutations of A>C and G>T in AsH group. Furthermore, 73% of the BlCa samples showed overexpression (mRNA/protein) of PIK3CA with genetic alterations (amplification/mutation), significantly (P = 0.01) higher in AsH group. However, 36% of the samples showed overexpressed PIK3CA, independent of mutation or amplification, signifying a transcriptional upregulation of PIK3CA gene. Therefore, the expression status of NFκB, a transcription factor of PIK3CA, was assessed and found to be significantly correlated with the overexpression of PIK3CA (mRNA/protein) in AsH group. Similarly, the expression pattern of pAKT1 (Thr 308) was also found to be significantly correlated with PIK3CA overexpression. Finally, AsH patients with the overexpression of PIK3CA or NFκB had the worst overall survival, signifying a strong impact of arsenic on this pathway and outcome of the patients. Thus, our study showed that the arsenic-associated differential molecular profile of PIK3CA/AKT1/NFkB in BlCa has an important role in the molecular pathogenesis of the disease.


Assuntos
Arsênio/toxicidade , Carcinoma/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/induzido quimicamente , Carcinoma/patologia , Variações do Número de Cópias de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Taxa de Mutação , Proteínas Proto-Oncogênicas c-akt/genética , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/patologia
5.
J Pathol ; 246(2): 134-140, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29952003

RESUMO

Geminin, a DNA replication licensing inhibitor, ensures faithful DNA replication in vertebrates. Several studies have shown that geminin depletion in vitro results in rereplication and DNA damage, whereas increased expression of geminin has been observed in human cancers. However, conditional inactivation of geminin during embryogenesis has not revealed any detectable DNA replication defects. In order to examine its role in vivo, we conditionally inactivated geminin in the murine colon and lung, and assessed chemically induced carcinogenesis. We show here that mice lacking geminin develop a significantly higher number of tumors and bear a larger tumor burden than sham-treated controls in urethane-induced lung and azoxymethane/dextran sodium sulfate-induced colon carcinogenesis. Survival is also significantly reduced in mice lacking geminin during lung carcinogenesis. A significant increase in the total number and grade of lesions (hyperplasias, adenomas, and carcinomas) was also confirmed by hematoxylin and eosin staining. Moreover, increased genomic aberrations, identified by increased ATR and γH2AX expression, was detected with immunohistochemistry analysis. In addition, we analyzed geminin expression in human colon cancer, and found increased expression, as well as a positive correlation with ATM/ATR levels and a non-monotonic association with γH2AX. Taken together, our data demonstrate that geminin acts as a tumor suppressor by safeguarding genome stability, whereas its overexpression is also associated with genomic instability. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenoma/genética , Carcinoma/genética , Neoplasias do Colo/genética , Geminina/genética , Genes Supressores de Tumor , Instabilidade Genômica , Neoplasias Pulmonares/genética , Adenoma/induzido quimicamente , Adenoma/metabolismo , Adenoma/patologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Azoximetano , Carcinoma/induzido quimicamente , Carcinoma/metabolismo , Carcinoma/patologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Geminina/deficiência , Geminina/metabolismo , Predisposição Genética para Doença , Histonas/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Fosforilação , Uretana
6.
J Pathol ; 246(3): 289-299, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30047135

RESUMO

Cadherin-17 is an adhesion molecule expressed specifically in intestinal epithelial cells. It is frequently underexpressed in human colorectal cancer. The physiological function of cadherin-17 and its role in tumourigenesis have not yet been determined. We used the transcription activator-like effector nuclease technique to generate a Cdh17 knockout (KO) mouse model. Intestinal tissues were analysed with histological, immunohistochemical and ultrastructural methods. Colitis was induced by oral administration of dextran sulphate sodium (DSS), and, to study effects on intestinal tumourigenesis, mice were given azoxymethane (AOM) and DSS to induce colitis-associated cancer. Cdh17 KO mice were viable and fertile. The histology of their small and large intestines was similar to that of wild-type mice. The junctional architecture of the intestinal epithelium was preserved. The loss of cadherin-17 resulted in increased permeability and susceptibility to DSS-induced colitis. The AOM/DSS model demonstrated that Cdh17 KO enhanced tumour formation and progression in the intestine. Increased nuclear translocation of Yap1, but not of ß-catenin, was identified in the tumours of Cdh17 KO mice. In conclusion, cadherin-17 plays a crucial role in intestinal homeostasis by limiting the permeability of the intestinal epithelium. Cadherin-17 is also a tumour suppressor for intestinal epithelia. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenoma/metabolismo , Caderinas/deficiência , Carcinoma/metabolismo , Colite/metabolismo , Neoplasias Colorretais/metabolismo , Absorção Intestinal , Mucosa Intestinal/metabolismo , Proteínas Supressoras de Tumor/deficiência , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenoma/induzido quimicamente , Adenoma/genética , Adenoma/patologia , Animais , Azoximetano , Caderinas/genética , Carcinoma/induzido quimicamente , Carcinoma/genética , Carcinoma/patologia , Proteínas de Ciclo Celular , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Deleção de Genes , Predisposição Genética para Doença , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Permeabilidade , Fenótipo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/genética , Proteínas de Sinalização YAP
7.
Gastroenterology ; 152(3): 631-643, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27825961

RESUMO

BACKGROUND & AIMS: Little is known about the mechanisms by which chronic inflammation contributes to carcinogenesis, such as the development of colon tumors in patients with inflammatory bowel diseases. Specific microRNA (miRNAs) can function as suppressors or oncogenes, and widespread alterations in miRNA expression have been associated with tumorigenesis. We studied whether alterations in miRNA function contribute to inflammation-associated colon carcinogenesis. METHODS: We studied the effects of inflammatory cytokines, such as tumor necrosis factor, interleukin-1α (IL1A), and IL1ß (IL1B), on miRNA function, measured by activity of reporter constructs containing miRNA-binding sites in their 3' untranslated regions, in human 293T embryonic kidney, Caco-2, HT29, and HCT116 colon carcinoma cells, as well as dicer+/+ and dicer-/-, and Apobec3+/+ and Apobec3-/- mouse embryonic fibroblasts. Cells were analyzed by immunoblots, immunohistochemistry, and flow cytometry. We generated transgenic mice expressing reporter constructs regulated by LET7B, MIR122, and MIR29b response elements; some mice were given injections of miRNA inhibitors (anti-MIR122 or anti-LET7B), a negative control, or tumor necrosis factor. Liver tissues were collected and analyzed by immunoblotting. Reporter mice were given azoxymethane followed by dextran sulfate sodium to induce colitis and colon tumors; some mice were given the ROCK inhibitor fasudil along with these agents (ROCK inhibitors increase miRNA function). Colon tissues were collected and analyzed by immunohistochemistry, immunoblots, and fluorescence microscopy. RESULTS: Incubation of cell lines with inflammatory cytokines reduced the ability of miRNAs to down-regulate expression from reporter constructs; dicer was required for this effect, so these cytokines relieve miRNA-dependent reductions in expression. The cytokines promoted degradation of APOBEC3G, which normally promotes miRNA loading into argonaute 2-related complexes. Mice with colitis had reduced miRNA function, based on increased expression of reporter genes. Administration of fasudil to mice did not reduce the severity of colitis that developed but greatly reduced the numbers of colon tumors formed (mean 2 tumors/colon in mice given fasudil vs 9 tumors/colon in mice given control agent). We made similar observations in IL10-deficient mice. CONCLUSIONS: We found inflammatory cytokines to reduce the activities of miRNAs. In mice with colitis, activities of miRNAs are reduced; administration of an agent that increases miRNA function prevents colon tumor formation in these mice. This pathway might be targeted to prevent colon carcinogenesis in patients with inflammatory bowel diseases.


Assuntos
Carcinogênese/efeitos dos fármacos , Carcinoma/genética , Colite/metabolismo , Colo/efeitos dos fármacos , Neoplasias do Colo/genética , Citocinas/farmacologia , Fibroblastos/efeitos dos fármacos , MicroRNAs/efeitos dos fármacos , Animais , Azoximetano/toxicidade , Células CACO-2 , Carcinogênese/genética , Carcinoma/induzido quimicamente , Linhagem Celular Tumoral , Colite/induzido quimicamente , Colo/metabolismo , Neoplasias do Colo/induzido quimicamente , Citidina Desaminase/genética , RNA Helicases DEAD-box/genética , Sulfato de Dextrana/toxicidade , Fibroblastos/metabolismo , Citometria de Fluxo , Células HCT116 , Células HT29 , Humanos , Immunoblotting , Imuno-Histoquímica , Inflamação , Interleucina-1alfa/farmacologia , Interleucina-1beta/farmacologia , Camundongos , MicroRNAs/genética , Ribonuclease III/genética , Fator de Necrose Tumoral alfa/farmacologia
8.
Toxicol Pathol ; 46(2): 184-192, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29390940

RESUMO

Lung cancer is the most common cause of cancer-related deaths in humans worldwide. There is strong evidence that the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and its metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) play an important role in carcinogenesis caused by tobacco products. NNK and racemic NNAL are reported to induce lung and pancreatic tumors in rats. The carcinogenicity in Fischer 344 rats of NNK, NNAL, and its enantiomers ( R)-NNAL and ( S)-NNAL has been studied recently, and all test compounds induced significant numbers of lung tumors. We report here the detailed histopathological and immunohistochemical characterization of these tumors and their aggressive nature as shown by their metastasis locally and to the pancreas. The spectrum of treatment-related histopathological findings comprised pulmonary alveolar/bronchiolar (A/B) epithelial hyperplasia, A/B adenomas, and A/B carcinomas. A/B carcinomas frequently exhibited local invasion/metastasis within the mediastinum and thoracic cavity and distant metastasis to the pancreas that was confirmed by immunohistochemistry using the lung-specific markers prosurfactant protein-C and club (Clara) cell-10. Our observation regarding metastasis to the pancreas was an important, and unexpected, finding in this study both for the experimental animal model and potential human relevance.


Assuntos
Carcinógenos/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Nitrosaminas/toxicidade , Neoplasias Pancreáticas/secundário , Animais , Carcinógenos/metabolismo , Carcinoma/induzido quimicamente , Carcinoma/secundário , Neoplasias Pulmonares/patologia , Masculino , Nitrosaminas/metabolismo , Ratos , Ratos Endogâmicos F344 , Estereoisomerismo , Nicotiana/química
9.
Tumour Biol ; 39(3): 1010428317695019, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28349837

RESUMO

5-Fluorouracil has been considered as a cornerstone therapy for colorectal cancer; however, it suffers from low therapeutic response rate and severe side effects. Therefore, there is an urgent need to increase the clinical efficacy of 5-fluorouracil. Recently, fish oil rich in n-3 polyunsaturated fatty acids has been reported to chemosensitize tumor cells to anti-cancer drugs. This study is designed to understand the underlying mechanisms of synergistic effect of fish oil and 5-fluorouracil by evaluation of tumor cell-associated markers such as apoptosis and DNA damage. The colon cancer was developed by administration of N,N-dimethylhydrazine dihydrochloride and dextran sulfate sodium salt. Further these animals were treated with 5-fluorouracil, fish oil, or a combination of both. In carcinogen-treated animals, a decrease in DNA damage and apoptotic index was observed. There was also a decrease in the expression of Fas, FasL, caspase 8, and Bax, and an increase in Bcl-2. In contrast, administration of 5-fluorouracil and fish oil as an adjuvant increased both DNA damage and apoptotic index by activation of both extrinsic and intrinsic apoptotic pathways as compared to the other groups. The increased pro-apoptotic effect by synergism of 5-fluorouracil and fish oil may be attributed to the incorporation of n-3 polyunsaturated fatty acids in membrane, which alters membrane fluidity in cancer cells. In conclusion, this study highlights that the induction of apoptotic pathway by fish oil may increase the susceptibility of tumors to chemotherapeutic regimens.


Assuntos
Carcinoma/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Óleos de Peixe/administração & dosagem , Fluoruracila/administração & dosagem , Neoplasias Experimentais/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Carcinoma/induzido quimicamente , Carcinoma/genética , Carcinoma/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Dano ao DNA/efeitos dos fármacos , Sulfato de Dextrana/toxicidade , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Metilistaminas/toxicidade , Camundongos , Proteínas de Neoplasias/biossíntese , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia
10.
Occup Environ Med ; 74(7): 502-510, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28202579

RESUMO

OBJECTIVES: To assess the associations between occupational exposure to biocides and pesticides and risk of thyroid cancer. METHODS: Using data from a population-based case-control study involving 462 incident thyroid cancer cases and 498 controls in Connecticut collected in 2010-2011, we examined the association with occupational exposure to biocides and pesticides through a job-exposure matrix. We used unconditional logistic regression models to estimate OR and 95% CI, adjusting for potential confounders. RESULTS: Individuals who were occupationally ever exposed to biocides had an increased risk of thyroid cancer (OR=1.65, 95% CI 1.16 to 2.35), and the highest risk was observed for the high cumulative probability of exposure (OR=2.18, 95% CI 1.28 to 3.73). The observed associations were similar when we restricted to papillary thyroid cancer and well-differentiated thyroid cancer. Stronger associations were observed for thyroid microcarcinomas (tumour size ≤1 cm). No significant association was observed for occupational exposure to pesticides. CONCLUSIONS: Our study provides the first evidence linking occupational exposure to biocides and risk of thyroid cancer. The results warrant further investigation.


Assuntos
Carcinoma/induzido quimicamente , Carcinoma/epidemiologia , Desinfetantes/efeitos adversos , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Praguicidas/efeitos adversos , Neoplasias da Glândula Tireoide/induzido quimicamente , Neoplasias da Glândula Tireoide/epidemiologia , Adulto , Idoso , Carcinoma Papilar , Estudos de Casos e Controles , Connecticut/epidemiologia , Feminino , Humanos , Entrevistas como Assunto , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Ocupações , Sistema de Registros , Fatores de Risco , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia
11.
Indian J Med Res ; 146(4): 468-475, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29434060

RESUMO

Background & objectives: Pioglitazone was suspended for manufacture and sale by the Indian drug regulator in June 2013 due to its association with urinary bladder carcinoma, which was revoked within a short period (July 2013). The present questionnaire-based nationwide study was conducted to assess its impact on prescribing behaviour of physicians in India. Methods: Between December 2013 and March 2014, a validated questionnaire was administered to physicians practicing diabetes across 25 centres in India. Seven hundred and forty questionnaires fulfilling the minimum quality criteria were included in the final analysis. Results: Four hundred and sixteen (56.2%) physicians prescribed pioglitazone. Of these, 281 used it in less than the recommended dose of 15 mg/day. Most physicians (94.3%) were aware of recent regulatory events. However, only 333 (44.8%) changed their prescribing pattern. Seventeen of the 416 (4.1%) physicians who prescribed pioglitazone admitted having come across at least one type 2 diabetes mellitus patient (T2DM) who had urinary bladder carcinoma, and of these 13 said that it was in patients who took pioglitazone for a duration of more than two years. Only 7.8 per cent of physicians (n=58) categorically advocated banning pioglitazone, and the rest opined for its continuation or generating more evidence before decision could be taken regarding its use in T2DM. Interpretation & conclusions: Majority of the physicians though were aware of the regulatory changes with regard to pioglitazone, but their prescribing patterns were not changed for this drug. However, it was being used at lower than the recommended dose. There is a need for generating more evidence through improved pharmacovigilance activities and large-scale population-based prospective studies regarding the safety issues of pioglitazone, so as to make effectual risk-benefit analysis for its continual use in T2DM.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Hipoglicemiantes/efeitos adversos , Médicos/ética , Tiazolidinedionas/efeitos adversos , Adulto , Idoso , Carcinoma/induzido quimicamente , Carcinoma/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Médicos/psicologia , Pioglitazona , Prescrições/normas , Inquéritos e Questionários , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/epidemiologia
12.
Am J Epidemiol ; 183(2): 110-21, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26672017

RESUMO

Alcohol is a carcinogen suspected of increasing lung cancer risk. Therefore, we prospectively evaluated the relationship between alcohol consumption and lung carcinoma in 492,902 persons from the National Institutes of Health-AARP Diet and Health Study. We used Cox models to calculate hazard ratios and 95% confidence intervals, adjusting for tobacco smoking and other potential confounders. Between 1995/1996 and December 31, 2006, there were 10,227 incident cases of lung carcinoma, classified as adenocarcinoma (n = 4,036), squamous cell carcinoma (n = 1,998), small cell carcinoma (n = 1,524), undifferentiated carcinoma (n = 559), and other (n = 2,110). Compared with nondrinking, alcohol consumption was associated with a modest nonlinear reduction in total lung carcinoma risk at lower levels of consumption (for 0.5-<1 drink/day, HR = 0.89, 95% confidence interval: 0.82, 0.96) but a modest increase in risk in the highest category (for ≥7 drinks/day, HR = 1.11, 95% confidence interval: 1.00, 1.24). Regarding histological type, alcohol was associated with a nonlinear reduction in squamous cell carcinoma that became attenuated as consumption increased and a modest increase in adenocarcinoma among heavier drinkers. Cubic spline models confirmed these findings. Our data suggest that the relationship between alcohol consumption and lung carcinoma differs by histological subtype.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Transtornos Induzidos por Álcool/complicações , Carcinoma/induzido quimicamente , Neoplasias Pulmonares/induzido quimicamente , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/epidemiologia , Adenocarcinoma de Pulmão , Idoso , Carcinoma/epidemiologia , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/epidemiologia , Feminino , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Carcinoma de Pequenas Células do Pulmão/induzido quimicamente , Carcinoma de Pequenas Células do Pulmão/epidemiologia , Fumar , Estados Unidos/epidemiologia
14.
Arch Toxicol ; 90(8): 1917-27, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26359225

RESUMO

Arsenic causes oxidative stress in cultured animal and human cells, and it is a well-documented human carcinogen. We conducted a hospital-based case-control study including 167 cases of urothelial carcinoma (UC) and 334 age- and gender-matched healthy controls to evaluate the relationships between urinary arsenic profiles, urinary 8-hydroxydeoxyguanosine (8-OHdG) levels, and human 8-oxoguanine DNA glycosylase (hOGG1) genotypes and UC. The urinary arsenic species were analyzed by high-performance liquid chromatography and hydride generator-atomic absorption spectrometry. Genotyping for hOGG1 (Ser326Cys) and hOGG1 (-15C>G) was performed using the Sequenom MassARRAY platform with iPLEX Gold chemistry. Urinary 8-OHdG was measured with high-sensitivity enzyme-linked immunosorbent assay kits. The results indicated that the hOGG1 326 Cys/Cys genotype and the hOGG1 -15C>G G/G genotype were associated with an increased risk of UC (OR [95 % CI] 1.57 [1.04-2.35] and 1.57 [1.04-2.35], respectively). Participants with high urinary total arsenic, regardless of the haplotype of hOGG1 Ser326Cys and the -15C>G polymorphism, had significantly higher urinary 8-OHdG compared to participants with low urinary total arsenic. This is the first study to investigate the joint effects of high urinary total arsenic or inefficient arsenic methylation capacity indices, and the high-risk G-G haplotype of hOGG1 on the risk of UC. The findings are especially meaningful for participants with risk factors such as high urinary total arsenic, inefficient arsenic methylation indices, high urinary 8-OHdG, and the high-risk G-G haplotype of hOGG1 which are all associated with an increased UC risk.


Assuntos
Arsênio/toxicidade , Carcinógenos Ambientais/toxicidade , Carcinoma/induzido quimicamente , DNA Glicosilases/genética , Desoxiguanosina/análogos & derivados , Polimorfismo de Nucleotídeo Único , Neoplasias Urológicas/induzido quimicamente , 8-Hidroxi-2'-Desoxiguanosina , Arsênio/urina , Carcinógenos Ambientais/metabolismo , Carcinoma/genética , Carcinoma/urina , Estudos de Casos e Controles , Interpretação Estatística de Dados , Desoxiguanosina/urina , Predisposição Genética para Doença , Genótipo , Humanos , Metilação , Fatores de Risco , Neoplasias Urológicas/genética , Neoplasias Urológicas/urina
15.
Arch Toxicol ; 90(11): 2809-2823, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26542539

RESUMO

Methyleugenol is a substituted alkenylbenzene found in several herbs and spices. It is classified by the European Union's Scientific Committee on Food as a genotoxic carcinogen. We addressed the biological mechanism of the genotoxic properties of methyleugenol and its oxidative metabolites. Methyleugenol and the oxidative metabolites significantly enhanced the DNA damage in human colon carcinoma cells (HT29). Methyleugenol did not affect the protein status of γH2AX, a biomarker of DNA double-strand breaks, whereas its metabolites methyleugenol-2',3'-epoxide and 3'-oxomethylisoeugenol significantly increased the cellular phosphorylated H2AX level. Both of these metabolites also showed a significant induction of micronuclei in HT29 cells. Furthermore, we investigated whether topoisomerase interaction contribute to the observed effect on DNA integrity. Methyleugenol-2',3'-epoxide and 3'-oxomethylisoeugenol inhibited the activity of recombinant topoisomerase I. In HT29 cells, neither methyleugenol nor the metabolites affected the level of topoisomerase protein bound to DNA, excluding a topoisomerase poisoning mode of action. In addition, 3'-oxomethylisoeugenol potently diminished the level of camptothecin-stabilized topoisomerase I/DNA intermediates and camptothecin-induced DNA strand breaks. In conclusion, it could be suggested that 3'-oxomethylisoeugenol may also interact with classical or food-borne topoisomerase I poisons, diminishing their poisoning effectiveness.


Assuntos
Carcinógenos Ambientais/toxicidade , Neoplasias do Colo/induzido quimicamente , Dano ao DNA , DNA Topoisomerases Tipo I/metabolismo , Eugenol/análogos & derivados , Mutagênicos/toxicidade , Inibidores da Topoisomerase I/toxicidade , Biomarcadores Tumorais/agonistas , Biomarcadores Tumorais/metabolismo , Biotransformação , Carcinógenos Ambientais/análise , Carcinógenos Ambientais/metabolismo , Carcinoma/induzido quimicamente , Carcinoma/enzimologia , Neoplasias do Colo/enzimologia , Neoplasias do Colo/metabolismo , Ensaio Cometa , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/genética , Compostos de Epóxi/análise , Compostos de Epóxi/metabolismo , Compostos de Epóxi/toxicidade , Eugenol/análise , Eugenol/metabolismo , Eugenol/toxicidade , Contaminação de Alimentos , Células HT29 , Histonas/agonistas , Histonas/metabolismo , Humanos , Testes para Micronúcleos , Mutagênicos/análise , Mutagênicos/metabolismo , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Oxirredução , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Especiarias/efeitos adversos , Especiarias/análise , Inibidores da Topoisomerase I/análise , Inibidores da Topoisomerase I/metabolismo
16.
Regul Toxicol Pharmacol ; 76: 63-73, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26774757

RESUMO

The carcinogenicity and chronic toxicity of hydrazine monohydrate was examined by administrating hydrazine monohydrate in drinking water to groups of 50 F344/DuCrj rats and 50 Crj:BDF1 mice of both sexes for two years. The drinking water concentration of hydrazine monohydrate was 0, 20, 40 or 80 ppm (wt/wt) for male and female rats and male mice; and 0, 40, 80 or 160 ppm for female mice. Survival rates of each group of males and females rats and mice were similar to the respective controls, except female rats administered 80 ppm. Two-year administration of hydrazine monohydrate produced an increase in the incidences of hepatocellular adenomas and carcinomas in rats of both sexes along with hepatic foci. In mice, the incidences of hepatocellular adenomas and carcinomas were increased in females, and significantly increased incidences of hepatocellular adenomas in females administered 160 ppm were observed. Thus, hydrazine monohydrate is carcinogenic in two species, rats and mice. Additionally, non-neoplastic renal lesions in rats and mice and non-neoplastic nasal lesions in mice were observed.


Assuntos
Adenoma/induzido quimicamente , Testes de Carcinogenicidade , Carcinógenos/toxicidade , Carcinoma/induzido quimicamente , Transformação Celular Neoplásica/induzido quimicamente , Água Potável , Hidrazinas/toxicidade , Neoplasias Hepáticas/induzido quimicamente , Testes de Toxicidade Crônica , Adenoma/sangue , Adenoma/patologia , Administração Oral , Animais , Biomarcadores/sangue , Peso Corporal/efeitos dos fármacos , Carcinógenos/administração & dosagem , Carcinoma/sangue , Carcinoma/patologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Hidrazinas/administração & dosagem , Rim/efeitos dos fármacos , Rim/patologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Nariz/efeitos dos fármacos , Nariz/patologia , Ratos Endogâmicos F344 , Medição de Risco , Fatores Sexuais , Especificidade da Espécie , Fatores de Tempo
17.
Hepatobiliary Pancreat Dis Int ; 14(2): 208-14, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25865695

RESUMO

BACKGROUND: 7, 12-dimethylbenzanthracene (DMBA)-induced pancreatic intraepithelial neoplasia (PanIN) and pancreatic cancer in rats provide a classic model for uncovering the molecular mechanisms underlying pancreatic cancer. However, this model has not been characterized genetically, and in particular, the major genetic alterations in the p16 gene are unknown. METHODS: Lesions of PanIN and pancreatic cancer were induced with DMBA implantation in 40 rats, and control pancreatic tissue was obtained from 10 age-matched rats without exposure to DMBA. Pancreatic tissue was harvested three months after DMBA implantation and DNA was extracted. Homozygous deletions and point mutations of the p16 (exons 1 and 2) gene were detected by PCR amplification and direct sequencing. RESULTS: DMBA implantation in the 40 rats induced 26 PanINs and 9 carcinomas. The overall frequency of p16 alterations in the pancreatic tissue of these rats was 42.86% (15/35), and the changes were point mutations, not homozygous deletions. p16 mutations were present in 30.77% (8/26) of the rats with PanIN and 77.78% (7/9) of the rats with carcinoma (P<0.05). The increasing incidence of p16 alterations was detected in 20.00% (1/5) of PanIN-1, 28.57% (2/7) of PanIN-2 and 35.71% (5/14) of PanIN-3 lesions. CONCLUSION: Our findings indicated that p16 alteration is a common event in the carcinogenesis of this model and that the mutation pattern is analogous to that of human lesions.


Assuntos
Carcinoma in Situ/genética , Carcinoma/genética , Genes p16 , Neoplasias Pancreáticas/genética , 9,10-Dimetil-1,2-benzantraceno , Animais , Carcinoma/induzido quimicamente , Carcinoma/patologia , Carcinoma in Situ/induzido quimicamente , Carcinoma in Situ/patologia , Modelos Animais de Doenças , Éxons , Masculino , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/patologia , Mutação Puntual , Ratos , Ratos Sprague-Dawley
18.
Annu Rev Physiol ; 73: 437-56, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21090967

RESUMO

Cigarette smoking is responsible for lung cancer and chronic obstructive pulmonary disease (COPD), the leading cause of death from cancer and the second-leading cause of death in the United States. In the United States, 46 million people smoke, with an equal number of former smokers. Moreover, 20-25% of current or former smokers will develop either disease, and smokers with one disease are at increased risk for developing the other. There are no tools for predicting risk of developing either disease; no accepted tools for early diagnosis of potentially curable lung cancer; and no tools for defining molecular pathways or molecular subtypes of these diseases, for predicting rate of progression, or for assessing response to therapy at a biochemical or molecular level. This review discusses current studies and the future potential of measuring global gene expression in epithelial cells that are in the airway field of injury and of using the genomic information derived to begin to answer some of the above questions.


Assuntos
Carcinoma/induzido quimicamente , Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/induzido quimicamente , Mucosa Respiratória/efeitos dos fármacos , Fumar/efeitos adversos , Animais , Carcinoma/epidemiologia , Carcinoma/fisiopatologia , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/fisiopatologia , Masculino , Camundongos , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Mucosa Respiratória/metabolismo , Fumar/epidemiologia , Fumar/fisiopatologia , Estados Unidos/epidemiologia
19.
Am J Epidemiol ; 180(5): 508-17, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25008104

RESUMO

We assessed whether different oral progestogens in hormone replacement therapy may differentially affect the risk of endometrial cancer, using data from the Etude Epidémiologique auprès de femmes de l'Education Nationale (E3N), a French cohort study (1992-2008). Hazard ratios and their confidence intervals were derived from Cox models. Among 65,630 postmenopausal women (mean follow-up: 10.8 years), 301 endometrial cancers occurred. Compared with never use, ever use of estrogen + micronized progesterone was associated with an increased risk of endometrial cancer (hazard ratio (HR) = 1.80, 95% confidence interval (CI): 1.38, 2.34) that was significantly more marked with longer duration of use (for ≤5 years, HR = 1.39 (95% CI: 0.99, 1.97); for >5 years, HR = 2.66 (95% CI: 1.87, 3.77)). Although use of estrogen + dydrogesterone was not associated overall with endometrial cancer risk (HR = 1.05, 95% CI: 0.76, 1.45), there was a significantly increased risk with long-term use compared with never use (for >5 years, HR = 1.69, 95% CI: 1.06, 2.70). Users of preparations containing other progesterone derivatives or a norsteroid derivative were not at significantly increased risk (HR = 0.79 (95% CI: 0.60, 1.05) and HR = 1.30 (95% CI: 0.85, 1.99), respectively). In conclusion, micronized progesterone and, to a lesser extent, dydrogesterone at the doses used in France may not be sufficient to prevent estrogen-induced endometrial cancers.


Assuntos
Carcinoma/induzido quimicamente , Didrogesterona/administração & dosagem , Neoplasias do Endométrio/induzido quimicamente , Terapia de Reposição de Estrogênios/efeitos adversos , Progestinas/administração & dosagem , Idoso , Carcinoma/prevenção & controle , Neoplasias do Endométrio/prevenção & controle , Terapia de Reposição de Estrogênios/tendências , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
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