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1.
CA Cancer J Clin ; 69(5): 402-429, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31283845

RESUMO

Mesothelioma affects mostly older individuals who have been occupationally exposed to asbestos. The global mesothelioma incidence and mortality rates are unknown, because data are not available from developing countries that continue to use large amounts of asbestos. The incidence rate of mesothelioma has decreased in Australia, the United States, and Western Europe, where the use of asbestos was banned or strictly regulated in the 1970s and 1980s, demonstrating the value of these preventive measures. However, in these same countries, the overall number of deaths from mesothelioma has not decreased as the size of the population and the percentage of old people have increased. Moreover, hotspots of mesothelioma may occur when carcinogenic fibers that are present in the environment are disturbed as rural areas are being developed. Novel immunohistochemical and molecular markers have improved the accuracy of diagnosis; however, about 14% (high-resource countries) to 50% (developing countries) of mesothelioma diagnoses are incorrect, resulting in inadequate treatment and complicating epidemiological studies. The discovery that germline BRCA1-asssociated protein 1 (BAP1) mutations cause mesothelioma and other cancers (BAP1 cancer syndrome) elucidated some of the key pathogenic mechanisms, and treatments targeting these molecular mechanisms and/or modulating the immune response are being tested. The role of surgery in pleural mesothelioma is controversial as it is difficult to predict who will benefit from aggressive management, even when local therapies are added to existing or novel systemic treatments. Treatment outcomes are improving, however, for peritoneal mesothelioma. Multidisciplinary international collaboration will be necessary to improve prevention, early detection, and treatment.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/análise , Mesotelioma/terapia , Neoplasias Pleurais/terapia , Pneumonectomia/métodos , Amianto/efeitos adversos , Austrália/epidemiologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Carcinogênese/patologia , Terapia Combinada/métodos , Erros de Diagnóstico , Europa (Continente)/epidemiologia , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Carga Global da Doença , Humanos , Incidência , Exposição por Inalação/efeitos adversos , Cooperação Internacional , Mesotelioma/diagnóstico , Mesotelioma/epidemiologia , Mesotelioma/etiologia , Terapia de Alvo Molecular/métodos , Exposição Ocupacional/efeitos adversos , Pleura/efeitos dos fármacos , Pleura/patologia , Pleura/cirurgia , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/epidemiologia , Neoplasias Pleurais/etiologia , Prognóstico , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Estados Unidos/epidemiologia
2.
Proc Natl Acad Sci U S A ; 120(39): e2307999120, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37729199

RESUMO

Asbestos is the main cause of malignant mesothelioma. Previous studies have linked asbestos-induced mesothelioma to the release of HMGB1 from the nucleus to the cytoplasm, and from the cytoplasm to the extracellular space. In the cytoplasm, HMGB1 induces autophagy impairing asbestos-induced cell death. Extracellularly, HMGB1 stimulates the secretion of TNFα. Jointly, these two cytokines kick-start a chronic inflammatory process that over time promotes mesothelioma development. Whether the main source of extracellular HMGB1 were the mesothelial cells, the inflammatory cells, or both was unsolved. This information is critical to identify the targets and design preventive/therapeutic strategies to interfere with asbestos-induced mesothelioma. To address this issue, we developed the conditional mesothelial HMGB1-knockout (Hmgb1ΔpMeso) and the conditional myelomonocytic-lineage HMGB1-knockout (Hmgb1ΔMylc) mouse models. We establish here that HMGB1 is mainly produced and released by the mesothelial cells during the early phases of inflammation following asbestos exposure. The release of HMGB1 from mesothelial cells leads to atypical mesothelial hyperplasia, and in some animals, this evolves over the years into mesothelioma. We found that Hmgb1ΔpMeso, whose mesothelial cells cannot produce HMGB1, show a greatly reduced inflammatory response to asbestos, and their mesothelial cells express and secrete significantly reduced levels of TNFα. Moreover, the tissue microenvironment in areas of asbestos deposits displays an increased fraction of M1-polarized macrophages compared to M2 macrophages. Supporting the biological significance of these findings, Hmgb1ΔpMeso mice showed a delayed and reduced incidence of mesothelioma and an increased mesothelioma-specific survival. Altogether, our study provides a biological explanation for HMGB1 as a driver of asbestos-induced mesothelioma.


Assuntos
Amianto , Proteína HMGB1 , Mesotelioma Maligno , Mesotelioma , Animais , Camundongos , Fator de Necrose Tumoral alfa/genética , Proteína HMGB1/genética , Mesotelioma/induzido quimicamente , Mesotelioma/genética , Amianto/toxicidade , Inflamação , Microambiente Tumoral
3.
Proc Natl Acad Sci U S A ; 120(4): e2217840120, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36656861

RESUMO

BAP1 is a powerful tumor suppressor gene characterized by haplo insufficiency. Individuals carrying germline BAP1 mutations often develop mesothelioma, an aggressive malignancy of the serosal layers covering the lungs, pericardium, and abdominal cavity. Intriguingly, mesotheliomas developing in carriers of germline BAP1 mutations are less aggressive, and these patients have significantly improved survival. We investigated the apparent paradox of a tumor suppressor gene that, when mutated, causes less aggressive mesotheliomas. We discovered that mesothelioma biopsies with biallelic BAP1 mutations showed loss of nuclear HIF-1α staining. We demonstrated that during hypoxia, BAP1 binds, deubiquitylates, and stabilizes HIF-1α, the master regulator of the hypoxia response and tumor cell invasion. Moreover, primary cells from individuals carrying germline BAP1 mutations and primary cells in which BAP1 was silenced using siRNA had reduced HIF-1α protein levels in hypoxia. Computational modeling and co-immunoprecipitation experiments revealed that mutations of BAP1 residues I675, F678, I679, and L691 -encompassing the C-terminal domain-nuclear localization signal- to A, abolished the interaction with HIF-1α. We found that BAP1 binds to the N-terminal region of HIF-1α, where HIF-1α binds DNA and dimerizes with HIF-1ß forming the heterodimeric transactivating complex HIF. Our data identify BAP1 as a key positive regulator of HIF-1α in hypoxia. We propose that the significant reduction of HIF-1α activity in mesothelioma cells carrying biallelic BAP1 mutations, accompanied by the significant reduction of HIF-1α activity in hypoxic tissues containing germline BAP1 mutations, contributes to the reduced aggressiveness and improved survival of mesotheliomas developing in carriers of germline BAP1 mutations.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Mesotelioma Maligno , Mesotelioma , Ubiquitina Tiolesterase , Humanos , Heterozigoto , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Mesotelioma/genética , Mesotelioma/metabolismo , Mesotelioma Maligno/genética , Mesotelioma Maligno/complicações , Mutação , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/metabolismo
4.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34815344

RESUMO

Carriers of heterozygous germline BAP1 mutations (BAP1+/-) are affected by the "BAP1 cancer syndrome." Although they can develop almost any cancer type, they are unusually susceptible to asbestos carcinogenesis and mesothelioma. Here we investigate why among all carcinogens, BAP1 mutations cooperate with asbestos. Asbestos carcinogenesis and mesothelioma have been linked to a chronic inflammatory process promoted by the extracellular release of the high-mobility group box 1 protein (HMGB1). We report that BAP1+/- cells secrete increased amounts of HMGB1, and that BAP1+/- carriers have detectable serum levels of acetylated HMGB1 that further increase when they develop mesothelioma. We linked these findings to our discovery that BAP1 forms a trimeric protein complex with HMGB1 and with histone deacetylase 1 (HDAC1) that modulates HMGB1 acetylation and its release. Reduced BAP1 levels caused increased ubiquitylation and degradation of HDAC1, leading to increased acetylation of HMGB1 and its active secretion that in turn promoted mesothelial cell transformation.


Assuntos
Amianto , Proteína HMGB1/química , Histona Desacetilase 1/química , Proteínas Supressoras de Tumor/química , Ubiquitina Tiolesterase/química , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese , Núcleo Celular/metabolismo , Feminino , Interação Gene-Ambiente , Mutação em Linhagem Germinativa , Proteína HMGB1/genética , Heterozigoto , Histona Desacetilase 1/genética , Incidência , Inflamação , Masculino , Mesotelioma/metabolismo , Camundongos , Mutação , Prognóstico , Ligação Proteica , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina/química , Ubiquitina Tiolesterase/metabolismo
5.
J Transl Med ; 21(1): 749, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880686

RESUMO

Mesothelioma is a cancer typically caused by asbestos. Mechanistically, asbestos carcinogenesis has been linked to the asbestos-induced release of HMGB1 from the nucleus to the cytoplasm, where HMGB1 promotes autophagy and cell survival, and to the extracellular space where HMGB1 promotes chronic inflammation and mesothelioma growth. Targeting HMGB1 inhibited asbestos carcinogenesis and the growth of mesothelioma. It is hoped that targeting HMGB1 will be a novel therapeutic strategy that benefits mesothelioma patients. Severe restrictions and/or a complete ban on the use of asbestos were introduced in the 80 and early 90s in the Western world. These measures have proven effective as the incidence of mesothelioma/per 100,000 persons is decreasing in these countries. However, the overall number of mesotheliomas in the Western world has not significantly decreased. There are several reasons for that which are discussed here: (1) the presence of asbestos in old constructions; (2) the development of rural areas containing asbestos or other carcinogenic mineral fibers in the terrain; (3) the discovery of an increasing fraction of mesotheliomas caused by germline genetic mutations of BAP1 and other tumor suppressor genes; (4) mesotheliomas caused by radiation therapy; (5) the overall increase in the population and of the fraction of older people who are much more susceptible to develop all types of cancers, including mesothelioma. In summary, the epidemiology of mesothelioma is changing, the ban on asbestos worked, there are opportunities to help mesothelioma patients especially those who develop in a background of germline mutations and there is the opportunity to prevent a mesothelioma epidemic in the developing world, where the use of asbestos is increasing exponentially. We hope that restrictive measures similar to those introduced in the Western world will soon be introduced in developing countries to prevent a mesothelioma epidemic.


Assuntos
Amianto , Proteína HMGB1 , Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Humanos , Amianto/toxicidade , Carcinogênese , Neoplasias Pulmonares/genética , Mesotelioma/epidemiologia , Mesotelioma/terapia , Mesotelioma Maligno/complicações , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/genética
6.
Nature ; 546(7659): 549-553, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28614305

RESUMO

BRCA1-associated protein 1 (BAP1) is a potent tumour suppressor gene that modulates environmental carcinogenesis. All carriers of inherited heterozygous germline BAP1-inactivating mutations (BAP1+/-) developed one and often several BAP1-/- malignancies in their lifetime, mostly malignant mesothelioma, uveal melanoma, and so on. Moreover, BAP1-acquired biallelic mutations are frequent in human cancers. BAP1 tumour suppressor activity has been attributed to its nuclear localization, where it helps to maintain genome integrity. The possible activity of BAP1 in the cytoplasm is unknown. Cells with reduced levels of BAP1 exhibit chromosomal abnormalities and decreased DNA repair by homologous recombination, indicating that BAP1 dosage is critical. Cells with extensive DNA damage should die and not grow into malignancies. Here we discover that BAP1 localizes at the endoplasmic reticulum. Here, it binds, deubiquitylates, and stabilizes type 3 inositol-1,4,5-trisphosphate receptor (IP3R3), modulating calcium (Ca2+) release from the endoplasmic reticulum into the cytosol and mitochondria, promoting apoptosis. Reduced levels of BAP1 in BAP1+/- carriers cause reduction both of IP3R3 levels and of Ca2+ flux, preventing BAP1+/- cells that accumulate DNA damage from executing apoptosis. A higher fraction of cells exposed to either ionizing or ultraviolet radiation, or to asbestos, survive genotoxic stress, resulting in a higher rate of cellular transformation. We propose that the high incidence of cancers in BAP1+/- carriers results from the combined reduced nuclear and cytoplasmic activities of BAP1. Our data provide a mechanistic rationale for the powerful ability of BAP1 to regulate gene-environment interaction in human carcinogenesis.


Assuntos
Cálcio/metabolismo , Transformação Celular Neoplásica , Citoplasma/metabolismo , Retículo Endoplasmático/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Mitocôndrias/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/metabolismo , Apoptose/genética , Amianto/toxicidade , Sinalização do Cálcio , Núcleo Celular/metabolismo , Sobrevivência Celular , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos da radiação , Células Cultivadas , Dano ao DNA , Epitélio , Fibroblastos , Interação Gene-Ambiente , Humanos , Ligação Proteica , Estabilidade Proteica , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Ubiquitina/metabolismo , Ubiquitina Tiolesterase/deficiência , Ubiquitina Tiolesterase/genética
7.
Proc Natl Acad Sci U S A ; 117(41): 25543-25552, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32999071

RESUMO

Asbestos causes malignant transformation of primary human mesothelial cells (HM), leading to mesothelioma. The mechanisms of asbestos carcinogenesis remain enigmatic, as exposure to asbestos induces HM death. However, some asbestos-exposed HM escape cell death, accumulate DNA damage, and may become transformed. We previously demonstrated that, upon asbestos exposure, HM and reactive macrophages releases the high mobility group box 1 (HMGB1) protein that becomes detectable in the tissues near asbestos deposits where HMGB1 triggers chronic inflammation. HMGB1 is also detectable in the sera of asbestos-exposed individuals and mice. Searching for additional biomarkers, we found higher levels of the autophagy marker ATG5 in sera from asbestos-exposed individuals compared to unexposed controls. As we investigated the mechanisms underlying this finding, we discovered that the release of HMGB1 upon asbestos exposure promoted autophagy, allowing a higher fraction of HM to survive asbestos exposure. HMGB1 silencing inhibited autophagy and increased asbestos-induced HM death, thereby decreasing asbestos-induced HM transformation. We demonstrate that autophagy was induced by the cytoplasmic and extracellular fractions of HMGB1 via the engagement of the RAGE receptor and Beclin 1 pathway, while nuclear HMGB1 did not participate in this process. We validated our findings in a novel unique mesothelial conditional HMGB1-knockout (HMGB1-cKO) mouse model. Compared to HMGB1 wild-type mice, mesothelial cells from HMGB1-cKO mice showed significantly reduced autophagy and increased cell death. Autophagy inhibitors chloroquine and desmethylclomipramine increased cell death and reduced asbestos-driven foci formation. In summary, HMGB1 released upon asbestos exposure induces autophagy, promoting HM survival and malignant transformation.


Assuntos
Amianto/efeitos adversos , Autofagia/efeitos dos fármacos , Transformação Celular Neoplásica/induzido quimicamente , Proteína HMGB1/metabolismo , Mesotelioma/metabolismo , Adulto , Idoso , Animais , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Exposição Ocupacional
8.
Proc Natl Acad Sci U S A ; 117(52): 33466-33473, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33318203

RESUMO

Rare biallelic BLM gene mutations cause Bloom syndrome. Whether BLM heterozygous germline mutations (BLM+/-) cause human cancer remains unclear. We sequenced the germline DNA of 155 mesothelioma patients (33 familial and 122 sporadic). We found 2 deleterious germline BLM+/- mutations within 2 of 33 families with multiple cases of mesothelioma, one from Turkey (c.569_570del; p.R191Kfs*4) and one from the United States (c.968A>G; p.K323R). Some of the relatives who inherited these mutations developed mesothelioma, while none with nonmutated BLM were affected. Furthermore, among 122 patients with sporadic mesothelioma treated at the US National Cancer Institute, 5 carried pathogenic germline BLM+/- mutations. Therefore, 7 of 155 apparently unrelated mesothelioma patients carried BLM+/- mutations, significantly higher (P = 6.7E-10) than the expected frequency in a general, unrelated population from the gnomAD database, and 2 of 7 carried the same missense pathogenic mutation c.968A>G (P = 0.0017 given a 0.00039 allele frequency). Experiments in primary mesothelial cells from Blm+/- mice and in primary human mesothelial cells in which we silenced BLM revealed that reduced BLM levels promote genomic instability while protecting from cell death and promoted TNF-α release. Blm+/- mice injected intraperitoneally with asbestos had higher levels of proinflammatory M1 macrophages and of TNF-α, IL-1ß, IL-3, IL-10, and IL-12 in the peritoneal lavage, findings linked to asbestos carcinogenesis. Blm+/- mice exposed to asbestos had a significantly shorter survival and higher incidence of mesothelioma compared to controls. We propose that germline BLM+/- mutations increase the susceptibility to asbestos carcinogenesis, enhancing the risk of developing mesothelioma.


Assuntos
Asbestose/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Mesotelioma/genética , RecQ Helicases/genética , Adulto , Idoso , Animais , Asbesto Crocidolita , Família , Feminino , Instabilidade Genômica , Heterozigoto , Humanos , Incidência , Inflamação/patologia , Masculino , Camundongos , Pessoa de Meia-Idade
9.
Opt Express ; 30(13): 23967-23977, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225067

RESUMO

The performance of the underwater optical communication (UWOC) systems was primarily limited by the low optical transmission efficiency due to the beam divergence and water interference. It has been proved in our previous works that holographic beam shaping can effectively increase the optical transmission efficiency and therefore the communication distances and speed. The conventional hologram optimisation method treated each pixel as an independent variable, leading to a large search space and a slow process. In this work, we proposed to use a small set of parameters to describe the beam shaping holograms that were able to limit the beam divergence and compensate for the wavefront distortion. This significantly reduced the number of variables to be optimised and enabled the optimisation to be more efficient and effective. In a proof-of-concept experiment based on the off-the-shelf components, the proposed method was able to generate the optimal hologram within 20 iterations while achieving a tenfold increase in the optical transmission efficiency for a 30 m link at 100 Mbps.

10.
J Cell Physiol ; 236(5): 3406-3419, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33107103

RESUMO

High-mobility group box 1 (HMGB1) was initially recognized as a ubiquitous nuclear protein involved in maintaining the nucleosome integrity and facilitating gene transcription. HMGB1 has since been reevaluated to be a prototypical damage-associated molecular pattern (DAMP) protein, and together with its exogenous counterpart, pathogen-associated molecular pattern (PAMP), completes the body's alarmin system against disturbances in homeostasis. HMGB1 can be released into the extracellular matrix (ECM) by either granulocytes or necrotic cells to serve as a chemotaxis/cytokine during infection, endotoxemia, hypoxia, ischemia-reperfusion events, and cancer. Different isoforms of HMGB1 present with distinctive physiological functions in ECM-fully-reduced HMGB1 (all thiol) acts as the initial damage signal to recruit circulating myeloid cells, disulfide HMGB1 behaves as a cytokine to activate macrophages and neutrophils, and both signals are turned off when HMGB1 is terminally oxidized into the final sulfonate form. Targeting HMGB1 constitutes a favorable therapeutic strategy for inflammation and inflammatory diseases. Antagonists such as ethyl pyruvate inhibit HMGB1 by interfering with its cytoplasmic exportation, while others such as glycyrrhizin directly bind to HMGB1 and render it unavailable for its receptors. The fact that a mixture of different HMGB1 isoforms is present in the ECM poses a challenge in pinpointing the exact role of an individual antagonist. A more discriminative probe for HMGB1 may be necessary to advance our knowledge of HMGB1, HMGB1 antagonists, and inflammatory-related diseases.


Assuntos
Endotoxemia/metabolismo , Proteína HMGB1/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Alarminas/metabolismo , Animais , Citocinas/metabolismo , Humanos
11.
Opt Express ; 29(7): 10556-10567, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820189

RESUMO

The phase flicker in digital liquid crystal on silicon (LCOS) device introduces temporal phase noise to the phase pattern displayed on the device. Such temporal phase noise could elevate the power of unwanted diffraction orders and ultimately cause crosstalk in optical switches based on the LCOS technology. Building on our previous work, this paper demonstrated an automated phase flicker optimisation process by using the genetic algorithm. The method developed in this work further shortened the optimisation process by 10x. It was also demonstrated that the optimised digital driving waveform set was able to reduce the crosstalk level in the optical switches by at least 3 dB.

12.
Opt Express ; 29(17): 26404-26417, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34615076

RESUMO

In this paper, we proposed and experimentally verified a diffraction-based optical beam shaping technique for underwater optical communication (UWOC) applications. The proposed method aimed to address the key issue in UWOC links, i.e., the high propagation loss experienced by the launched optical beam. It enabled a significantly higher portion of the launched signal to be collected by the receiver. The optimal transmission distance could also be fine-tuned by the software configuration. In a proof-of-concept demonstration based on the off-the-shelf components, 100 Mbps transmission was achieved over 15-meter distance and a significant enhancement in the transmission quality was observed. There is a huge scope for further improvement in the transmission distance and data rate when the proposed technique was used with purpose-built optical components and advanced coding schemes.

13.
Curr Microbiol ; 77(8): 1610-1621, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32274531

RESUMO

ISP-SW5 is an intracellular alkaline serine protease gene from Bacillus velezensis SW5 that was heterologously expressed in Escherichia coli BL21 (DE3). Sequence analysis indicated that the ISP-SW5 gene has 960 bp open reading frame and encodes a protein of 319 amino acid residues. Three-dimensional structure of ISP-SW5 with the fibrinolytic activity from Bacillus velezensis was predicted by in silico analysis. Gly219 was the most likely active site for the fibrinolytic activity of ISP-SW5. The recombinant enzyme ISP-SW5 was purified by Ni-NTA Superflow Column. SDS-PAGE showed that this enzyme had a molecular mass of 34 kDa. The result of native-PAGE and N-terminal sequencing showed that the N-terminal propeptide of ISP-SW5 was cleaved during the maturation of protease. The optimum pH and temperature were 8.0 and 40 °C, respectively. Enzyme activity was markedly inhibited by PMSF and EDTA but enhanced by 5 mM Ca2+ and 2 mM Zn2+ by up to 143% and 115%, respectively. Additionally, ISP-SW5 retained 93%, 78%, and 49% relative enzyme activity after incubation with 0.5 M, 1 M and 2 M NaCl, respectively, at 4 °C for 12 h. The enzyme activity determined by casein as substrate was 1261 U/mg. ISP-SW5 could degrade fibrin at an activity of 3428 U/mg, and its properties reflect its potential application in developing a novel biological catalyst for efficient fibrin hydrolysis in medical treatment.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/química , Endopeptidases/química , Fibrinólise , Serina Proteases/química , Proteínas de Bactérias/metabolismo , Caseínas/metabolismo , Clonagem Molecular , Endopeptidases/metabolismo , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Serina Proteases/metabolismo , Temperatura
14.
Proc Natl Acad Sci U S A ; 113(47): 13432-13437, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27834213

RESUMO

We used a custom-made comparative genomic hybridization array (aCGH; average probe interval 254 bp) to screen 33 malignant mesothelioma (MM) biopsies for somatic copy number loss throughout the 3p21 region (10.7 Mb) that harbors 251 genes, including BRCA1 (breast cancer 1)-associated protein 1 (BAP1), the most commonly mutated gene in MM. We identified frequent minute biallelic deletions (<3 kb) in 46 of 251 genes: four were cancer-associated genes: SETD2 (SET domain-containing protein 2) (7 of 33), BAP1 (8 of 33), PBRM1 (polybromo 1) (3 of 33), and SMARCC1 (switch/sucrose nonfermentable- SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily c, member 1) (2 of 33). These four genes were further investigated by targeted next-generation sequencing (tNGS), which revealed sequence-level mutations causing biallelic inactivation. Combined high-density aCGH and tNGS revealed biallelic gene inactivation in SETD2 (9 of 33, 27%), BAP1 (16 of 33, 48%), PBRM1 (5 of 33, 15%), and SMARCC1 (2 of 33, 6%). The incidence of genetic alterations detected is much higher than reported in the literature because minute deletions are not detected by NGS or commercial aCGH. Many of these minute deletions were not contiguous, but rather alternated with segments showing oscillating copy number changes along the 3p21 region. In summary, we found that in MM: (i) multiple minute simultaneous biallelic deletions are frequent in chromosome 3p21, where they occur as distinct events involving multiple genes; (ii) in addition to BAP1, mutations of SETD2, PBRM1, and SMARCC1 are frequent in MM; and (iii) our results suggest that high-density aCGH combined with tNGS provides a more precise estimate of the frequency and types of genes inactivated in human cancer than approaches based exclusively on NGS strategy.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Hibridização Genômica Comparativa , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Pulmonares/genética , Mesotelioma/genética , Alelos , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA/genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Genoma Humano , Humanos , Mesotelioma Maligno , Família Multigênica , Mutação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes
15.
Nitric Oxide ; 76: 6-15, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29510200

RESUMO

Nitric oxide (NO) has a general inhibitory effects on chlorophyll biosynthesis, especially to the step of 5-aminolevulinic acid (ALA) biosynthesis and protochlorophyllide (Pchlide) to chlorophyllide (Chlide) conversion (responsible by the NADPH:Pchlide oxidoreductase POR). Previous study suggested that barley large POR aggregates may be generated by dithiol oxidation of cysteines of two POR monomers, which can be disconnected by some reducing agents. POR aggregate assembly may be correlated with seedling greening in barley, but not in Arabidopsis. Thus, NO may affect POR activity and seedling greening differently between Arabidopsis and barley. We proved this assumption by non-denaturing gel-analysis and reactive oxygen species (ROS) monitoring during the greening. NO treatments cause S-nitrosylation to POR cysteine residues and disassembly of POR aggregates. This modification reduces POR activity and induces Pchlide accumulation and singlet oxygen generation upon dark-to-high-light shift (and therefore inducing photobleaching lesions) in barley leaf apex, but not in Arabidopsis seedlings. ROS staining and ROS-related-gene expression detection confirmed that superoxide anion and singlet oxygen accumulated in barley etiolated seedlings after the NO treatments, when exposed to a fluctuating light. The data suggest that POR aggregate assembly may be correlated with barley chlorophyll biosynthesis and redox homeostasis during greening. Cysteine S-nitrosylation may be one of the key reasons for the NO-induced inhibition to chlorophyll biosynthetic enzymes.


Assuntos
Arabidopsis/metabolismo , Clorofilídeos/biossíntese , Hordeum/metabolismo , Óxido Nítrico/metabolismo , Oxigênio Singlete/metabolismo
16.
PLoS Genet ; 11(12): e1005633, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26683624

RESUMO

We recently discovered an inherited cancer syndrome caused by BRCA1-Associated Protein 1 (BAP1) germline mutations, with high incidence of mesothelioma, uveal melanoma and other cancers and very high penetrance by age 55. To identify families with the BAP1 cancer syndrome, we screened patients with family histories of multiple mesotheliomas and melanomas and/or multiple cancers. We identified four families that shared an identical BAP1 mutation: they lived across the US and did not appear to be related. By combining family histories, molecular genetics, and genealogical approaches, we uncovered a BAP1 cancer syndrome kindred of ~80,000 descendants with a core of 106 individuals, whose members descend from a couple born in Germany in the early 1700s who immigrated to North America. Their descendants spread throughout the country with mutation carriers affected by multiple malignancies. Our data show that, once a proband is identified, extended analyses of these kindreds, using genomic and genealogical studies to identify the most recent common ancestor, allow investigators to uncover additional branches of the family that may carry BAP1 mutations. Using this knowledge, we have identified new branches of this family carrying BAP1 mutations. We have also implemented early-detection strategies that help identify cancers at early-stage, when they can be cured (melanomas) or are more susceptible to therapy (MM and other malignancies).


Assuntos
Predisposição Genética para Doença , Melanoma/genética , Mesotelioma/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uveais/genética , Feminino , Genealogia e Heráldica , Mutação em Linhagem Germinativa , Alemanha , Humanos , Masculino , Melanoma/patologia , Mesotelioma/patologia , Linhagem , Estados Unidos , Neoplasias Uveais/patologia
17.
J Transl Med ; 15(1): 58, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28298211

RESUMO

BACKGROUND: Malignant mesothelioma (MM) is a very aggressive type of cancer, with a dismal prognosis and inherent resistance to chemotherapeutics. Development and evaluation of new therapeutic approaches is highly needed. Immunosuppressant FTY720, approved for multiple sclerosis treatment, has recently raised attention for its anti-tumor activity in a variety of cancers. However, its therapeutic potential in MM has not been evaluated yet. METHODS: Cell viability and anchorage-independent growth were evaluated in a panel of MM cell lines and human mesothelial cells (HM) upon FTY720 treatment to assess in vitro anti-tumor efficacy. The mechanism of action of FTY720 in MM was assessed by measuring the activity of phosphatase protein 2A (PP2A)-a major target of FTY720. The binding of the endogenous inhibitor SET to PP2A in presence of FTY720 was evaluated by immunoblotting and immunoprecipitation. Signaling and activation of programmed cell death were evaluated by immunoblotting and flow cytometry. A syngeneic mouse model was used to evaluate anti-tumor efficacy and toxicity profile of FTY720 in vivo. RESULTS: We show that FTY720 significantly suppressed MM cell viability and anchorage-independent growth without affecting normal HM cells. FTY720 inhibited the phosphatase activity of PP2A by displacement of SET protein, which appeared overexpressed in MM, as compared to HM cells. FTY720 promoted AKT dephosphorylation and Bcl-2 degradation, leading to induction of programmed cell death, as demonstrated by caspase-3 and PARP activation, as well as by cytochrome c and AIF intracellular translocation. Moreover, FTY720 administration in vivo effectively reduced tumor burden in mice without apparent toxicity. CONCLUSIONS: Our preclinical data indicate that FTY720 is a potentially promising therapeutic agent for MM treatment.


Assuntos
Cloridrato de Fingolimode/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/toxicidade , Mesotelioma Maligno , Camundongos , Proteína Fosfatase 2/metabolismo , Proteínas Supressoras de Tumor/metabolismo
18.
Opt Express ; 24(11): 12240-53, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27410140

RESUMO

Two-dimensional beam steering by small, square, phase patterns as small as 50 × 50 pixels on a phase-only liquid crystal on silicon (LCOS) device is experimentally verified as suitable for the application of wavelength selective switches (WSSs), in terms of the diffraction efficiency and steering accuracy. This enables a proposed highly functional and versatile stacked switch architecture, where 40 independent 1 × 12 WSSs can be realised on a single 4k LCOS device. They can be configured to support a 1 × N WSSs with N≤144, or an N × N wavelength crossconnect with N≤12.

19.
J Toxicol Environ Health B Crit Rev ; 19(5-6): 213-230, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27705545

RESUMO

Similar to asbestos fibers, nonregulated mineral fibers can cause malignant mesothelioma (MM). Recently, increased proportions of women and young individuals with MM were identified in southern Nevada, suggesting that environmental exposure to carcinogenic fibers was causing the development of MM. Palygorskite, a fibrous silicate mineral with a history of possible carcinogenicity, is abundant in southern Nevada. In this study, our aim was to determine whether palygorskite was contributing to the development of MM in southern Nevada. While palygorskite, in vitro, displayed some cytotoxicity toward primary human mesothelial (HM) cells and reduced their viability, the effects were roughly half of those observed when using similar amounts of crocidolite asbestos. No Balb/c (0/19) or MexTAg (0/18) mice injected with palygorskite developed MM, while 3/16 Balb/c and 13/14 MexTAg mice injected with crocidolite did. Lack of MM development was associated with a decreased acute inflammatory response, as injection of palygorskite resulted in lower percentages of macrophages (p = .006) and neutrophils (p = .02) in the peritoneal cavity 3 d after exposure compared to injection of crocidolite. Additionally, compared to mice injected with crocidolite, palygorskite-injected mice had lower percentages of M2 (tumor-promoting) macrophages (p = .008) in their peritoneal cavities when exposed to fiber for several weeks. Our study indicates that palygorskite found in the environment in southern Nevada does not cause MM in mice, seemingly because palygorskite, in vivo, fails to elicit inflammation that is associated with MM development. Therefore, palygorskite is not a likely contributor to the MM cases observed in southern Nevada.


Assuntos
Células Epiteliais/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Compostos de Magnésio/toxicidade , Mesotelioma/patologia , Compostos de Silício/toxicidade , Animais , Células Epiteliais/citologia , Neoplasias Pulmonares/induzido quimicamente , Mesotelioma/induzido quimicamente , Mesotelioma Maligno , Camundongos , Camundongos Endogâmicos BALB C , Nevada
20.
Carcinogenesis ; 36(1): 76-81, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25380601

RESUMO

BRCA1-associated protein-1 (BAP1) mutations cause a new cancer syndrome, with a high rate of malignant mesothelioma (MM). Here, we tested the hypothesis that MM associated with germline BAP1 mutations has a better prognosis compared with sporadic MM. We compared survival among germline BAP1 mutation MM patients with that of all MM (N = 10 556) recorded in the United States Surveillance, Epidemiology, and End Results (SEER) data from 1973 to 2010. We identified 23 MM patients--11 alive--with germline BAP1 mutations and available data on survival. Ten patients had peritoneal MM, ten pleural MM and three MM in both locations. Thirteen patients had one or more malignancies in addition to MM. Actuarial median survival for the MM patients with germline BAP1 mutations was 5 years, as compared with <1 year for the median survival in the United States SEER MM group. Five-year survival was 47%, 95% confidence interval (24-67%), as compared with 6.7% (6.2-7.3%) in the control SEER group. Analysis of the pooled cohort of germline BAP1 mutation MM showed that patients with peritoneal MM (median survival of 10 years, P = 0.0571), or with a second malignancy in addition to MM (median survival of 10 years, P = 0.0716), survived for a longer time compared with patients who only had pleural MM, or MM patients without a second malignancy, respectively. In conclusion, we found that MM patients with germline BAP1 mutations have an overall 7-fold increased long-term survival, independently of sex and age. Appropriate genetic counseling and clinical management should be considered for MM patients who are also BAP1 mutation carriers.


Assuntos
Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Neoplasias Pulmonares/genética , Mesotelioma/genética , Segunda Neoplasia Primária/genética , Neoplasias Peritoneais/genética , Neoplasias Pleurais/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Mesotelioma/mortalidade , Mesotelioma Maligno , Pessoa de Meia-Idade , Segunda Neoplasia Primária/mortalidade , Neoplasias Peritoneais/mortalidade , Neoplasias Pleurais/mortalidade , Prognóstico , Programa de SEER , Taxa de Sobrevida
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