Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Immunol Lett ; 270: 106912, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39237041

RESUMO

Inflammatory bowel diseases (IBD) are chronic relapsing disorders with increasing prevalence. Knowledge gaps still limit the possibility to develop more specific and effective therapies. Using a dextran sodium sulfate colitis mouse model, we found that inflammation increased the total number and altered the frequencies of leukocytes within colon mesenteric lymph nodes (cMLNs). Although the inflammation reduced the frequency of regulatory T (Treg) cells, their absolute numbers were increased. Increased frequency of colitogenic Th17 cells was also observed. Noteworthy, untreated mice lacking Poly(ADP-ribose)-Polimerase-1 functional gene (PARP-1KO) displayed higher frequency of Treg cells and lower percentage of Th17 cells in cMLNs. In colitic PARP-1KO mice the inflammation driven expansion of the Foxp3 Treg population was more pronounced than in WT mice. Conversely, colitis increased Th17 cells to a lower extent in PARP-1KO mice compared with WT mice, resulting in a more protective Treg/Th17 cell ratio. Consequently PARP-1KO mice developed less severe colitis with reduced expression of inflammatory cytokines. In ex vivo experiments PARP-1KO and WT CD11c dendritic cells (DCs) promoted naïve CD4 T cell differentiation differently, the former sustaining more efficiently the generation of Treg cells, the latter that of Th17 cells. Addition of HMGB1 B box or of dipotassium glycyrrhizate, which sequesters extracellular HMGB1, revealed a role for this alarmin in the regulation exerted by PARP-1 on the stimulating vs. tolerogenic function of DCs during colitis. Moreover, a higher percentage of CD11c DC from PARP-1KO mice expressed CD103, a marker associated with the ability of DC to induce Treg cells, compared with WT DC. Conversely, PARP-1KO DC were including a reduced percentage of CX3CR1+ DC, described to induce Th17 cells. These findings were observed in both splenic and colon lamina propria DC.

2.
Proc Natl Acad Sci U S A ; 121(29): e2405231121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38990952

RESUMO

We report that ~1.8% of all mesothelioma patients and 4.9% of those younger than 55, carry rare germline variants of the BRCA1 associated RING domain 1 (BARD1) gene that were predicted to be damaging by computational analyses. We conducted functional assays, essential for accurate interpretation of missense variants, in primary fibroblasts that we established in tissue culture from a patient carrying the heterozygous BARD1V523A mutation. We found that these cells had genomic instability, reduced DNA repair, and impaired apoptosis. Investigating the underlying signaling pathways, we found that BARD1 forms a trimeric protein complex with p53 and SERCA2 that regulates calcium signaling and apoptosis. We validated these findings in BARD1-silenced primary human mesothelial cells exposed to asbestos. Our study elucidated mechanisms of BARD1 activity and revealed that heterozygous germline BARD1 mutations favor the development of mesothelioma and increase the susceptibility to asbestos carcinogenesis. These mesotheliomas are significantly less aggressive compared to mesotheliomas in asbestos workers.


Assuntos
Sinalização do Cálcio , Reparo do DNA , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Mesotelioma , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Humanos , Reparo do DNA/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Mesotelioma/genética , Sinalização do Cálcio/genética , Feminino , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Apoptose/genética , Fibroblastos/metabolismo , Amianto/toxicidade , Instabilidade Genômica
3.
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
4.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240150

RESUMO

Pelvic radiation disease (PRD), a frequent side effect in patients with abdominal/pelvic cancers treated with radiotherapy, remains an unmet medical need. Currently available preclinical models have limited applications for the investigation of PRD pathogenesis and possible therapeutic strategies. In order to select the most effective irradiation protocol for PRD induction in mice, we evaluated the efficacy of three different locally and fractionated X-ray exposures. Using the selected protocol (10 Gy/day × 4 days), we assessed PRD through tissue (number and length of colon crypts) and molecular (expression of genes involved in oxidative stress, cell damage, inflammation, and stem cell markers) analyses at short (3 h or 3 days after X-ray) and long (38 days after X-rays) post-irradiation times. The results show that a primary damage response in term of apoptosis, inflammation, and surrogate markers of oxidative stress was found, thus determining a consequent impairment of cell crypts differentiation and proliferation as well as a local inflammation and a bacterial translocation to mesenteric lymph nodes after several weeks post-irradiation. Changes were also found in microbiota composition, particularly in the relative abundance of dominant phyla, related families, and in alpha diversity indices, as an indication of dysbiotic conditions induced by irradiation. Fecal markers of intestinal inflammation, measured during the experimental timeline, identified lactoferrin, along with elastase, as useful non-invasive tools to monitor disease progression. Thus, our preclinical model may be useful to develop new therapeutic strategies for PRD treatment.


Assuntos
Lesões por Radiação , Camundongos , Animais , Raios X , Modelos Animais de Doenças , Apoptose/efeitos da radiação , Inflamação
5.
Int J Mol Sci ; 24(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240259

RESUMO

Sonic hedgehog medulloblastoma (SHH-MB) accounts for 25-30% of all MBs, and conventional therapy results in severe long-term side effects. New targeted therapeutic approaches are urgently needed, drawing also on the fields of nanoparticles (NPs). Among these, plant viruses are very promising, and we previously demonstrated that tomato bushy stunt virus (TBSV), functionalized on the surface with CooP peptide, specifically targets MB cells. Here, we tested the hypothesis that TBSV-CooP can specifically deliver a conventional chemotherapeutic drug (i.e., doxorubicin, DOX) to MB in vivo. To this aim, a preclinical study was designed to verify, by histological and molecular methods, if multiple doses of DOX-TBSV-CooP were able to inhibit tumor progression of MB pre-neoplastic lesions, and if a single dose was able to modulate pro-apoptotic/anti-proliferative molecular signaling in full-blown MBs. Our results demonstrate that when DOX is encapsulated in TBSV-CooP, its effects on cell proliferation and cell death are similar to those obtained with a five-fold higher dose of non-encapsulated DOX, both in early and late MB stages. In conclusion, these results confirm that CooP-functionalized TBSV NPs are efficient carriers for the targeted delivery of therapeutics to brain tumors.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , Nanopartículas , Tombusvirus , Camundongos , Animais , Meduloblastoma/metabolismo , Preparações Farmacêuticas , Proteínas Hedgehog/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias Cerebelares/metabolismo , Nanopartículas/química
6.
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
7.
Cancers (Basel) ; 14(14)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35884524

RESUMO

Recent reports have shown a link between radiation exposure and non-cancer diseases such as radiation-induced heart disease (RIHD). Radiation exposures are often inhomogeneous, and out-of-target effects have been studied in terms of cancer risk, but very few studies have been carried out for non-cancer diseases. Here, the role of miRNAs in the pathogenesis of RIHD was investigated. C57Bl/6J female mice were whole- (WBI) or partial-body-irradiated (PBI) with 2 Gy of X-rays or sham-irradiated (SI). In PBI exposure, the lower third of the mouse body was irradiated, while the upper two-thirds were shielded. From all groups, hearts were collected 15 days or 6 months post-irradiation. The MiRNome analysis at 15 days post-irradiation showed that miRNAs, belonging to the myomiR family, were highly differentially expressed in WBI and PBI mouse hearts compared with SI hearts. Raman spectral data collected 15 days and 6 months post-irradiation showed biochemical differences among SI, WBI and PBI mouse hearts. Fibrosis in WBI and PBI mouse hearts, indicated by the increased deposition of collagen and the overexpression of genes involved in myofibroblast activation, was found 6 months post-irradiation. Using an in vitro co-culture system, involving directly irradiated skeletal muscle and unirradiated ventricular cardiac human cells, we propose the role of miR-1/133a as mediators of the abscopal response, suggesting that miRNA-based strategies could be relevant for limiting tissue-dependent reactions in non-directly irradiated tissues.

8.
Biochem Biophys Res Commun ; 610: 15-22, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35430447

RESUMO

The transcription factor p63, belonging to the p53 family, is considered the master regulator of epidermal differentiation, skin, and in general of the differentiation of ectodermal tissues. Mutations in TP63 gene cause several rare ectodermal dysplasia disorders that refers to epidermal structural abnormalities and ocular surface disease, such as Ectrodactyly Ectodermal Dysplasia Clefting (EEC) syndrome. In this review, we discuss the key roles of p63 in keratinocytes and corneal epithelial differentiation, highlighting the function of the ΔNp63α isoform in driving limbal stem cell and epithelial stem cells commitment. We have summarized the specific ocular phenotypes observed in the TP63-mutation derived EEC syndrome, discussing the current and novel therapeutic strategies for the management of the ocular manifestations in EEC syndrome.


Assuntos
Fenda Labial , Fissura Palatina , Displasia Ectodérmica , Fenda Labial/tratamento farmacológico , Fissura Palatina/tratamento farmacológico , Displasia Ectodérmica/tratamento farmacológico , Displasia Ectodérmica/genética , Humanos , Fatores de Transcrição/química , Fatores de Transcrição/genética
9.
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
10.
Int J Mol Sci ; 22(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34638864

RESUMO

Medulloblastoma (MB) is a primary central nervous system tumor affecting mainly young children. New strategies of drug delivery are urgent to treat MB and, in particular, the SHH-dependent subtype-the most common in infants-in whom radiotherapy is precluded due to the severe neurological side effects. Plant virus nanoparticles (NPs) represent an innovative solution for this challenge. Tomato bushy stunt virus (TBSV) was functionally characterized as a carrier for drug targeted delivery to a murine model of Shh-MB. The TBSV NPs surface was genetically engineered with peptides for brain cancer cell targeting, and the modified particles were produced on a large scale using Nicotiana benthamiana plants. Tests on primary cultures of Shh-MB cells allowed us to define the most efficient peptides able to induce specific uptake of TBSV. Immunofluorescence and molecular dynamics simulations supported the hypothesis that the specific targeting of the NPs was mediated by the interaction of the peptides with their natural partners and reinforced by the presentation in association with the virus. In vitro experiments demonstrated that the delivery of Doxorubicin through the chimeric TBSV allowed reducing the dose of the chemotherapeutic agent necessary to induce a significant decrease in tumor cells viability. Moreover, the systemic administration of TBSV NPs in MB symptomatic mice, independently of sex, confirmed the ability of the virus to reach the tumor in a specific manner. A significant advantage in the recognition of the target appeared when TBSV NPs were functionalized with the CooP peptide. Overall, these results open new perspectives for the use of TBSV as a vehicle for the targeted delivery of chemotherapeutics to MB in order to reduce early and late toxicity.


Assuntos
Neoplasias Cerebelares , Doxorrubicina , Sistemas de Liberação de Medicamentos , Proteínas Hedgehog/metabolismo , Meduloblastoma , Nanopartículas , Proteínas de Neoplasias/metabolismo , Tombusvirus/química , Animais , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Proteínas Hedgehog/genética , Meduloblastoma/tratamento farmacológico , Meduloblastoma/genética , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos , Camundongos Mutantes , Nanopartículas/química , Nanopartículas/uso terapêutico , Proteínas de Neoplasias/genética , Nicotiana/virologia
11.
Mol Oncol ; 15(11): 2823-2840, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34245122

RESUMO

Cancer genomes have been explored from the early 2000s through massive exome sequencing efforts, leading to the publication of The Cancer Genome Atlas in 2013. Sequencing techniques have been developed alongside this project and have allowed scientists to bypass the limitation of costs for whole-genome sequencing (WGS) of single specimens by developing more accurate and extensive cancer sequencing projects, such as deep sequencing of whole genomes and transcriptomic analysis. The Pan-Cancer Analysis of Whole Genomes recently published WGS data from more than 2600 human cancers together with almost 1200 related transcriptomes. The application of WGS on a large database allowed, for the first time in history, a global analysis of features such as molecular signatures, large structural variations and noncoding regions of the genome, as well as the evaluation of RNA alterations in the absence of underlying DNA mutations. The vast amount of data generated still needs to be thoroughly deciphered, and the advent of machine-learning approaches will be the next step towards the generation of personalized approaches for cancer medicine. The present manuscript wants to give a broad perspective on some of the biological evidence derived from the largest sequencing attempts on human cancers so far, discussing advantages and limitations of this approach and its power in the era of machine learning.


Assuntos
Genoma Humano , Neoplasias , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação/genética , Neoplasias/genética , Sequenciamento do Exoma , Sequenciamento Completo do Genoma/métodos
12.
Sci Rep ; 11(1): 8118, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854097

RESUMO

A radiological or nuclear attack could involve such a large number of subjects as to overwhelm the emergency facilities in charge. Resources should therefore be focused on those subjects needing immediate medical attention and care. In such a scenario, for the triage management by first responders, it is necessary to count on efficient biological dosimetry tools capable of early detection of the absorbed dose. At present the validated assays for measuring the absorbed dose are dicentric chromosomes and micronuclei counts, which require more than 2-3 days to obtain results. To overcome this limitation the NATO SPS Programme funded an Italian-Egyptian collaborative project aimed at validating a fast, accurate and feasible tool for assessing the absorbed dose early after radiation exposure. Biomarkers as complete blood cell counts, DNA breaks and radio-inducible proteins were investigated on blood samples collected before and 3 h after the first fraction of radiotherapy in patients treated in specific target areas with doses/fraction of about: 2, 3.5 or > 5 Gy and compared with the reference micronuclei count. Based on univariate and multivariate multiple linear regression correlation, our results identify five early biomarkers potentially useful for detecting the extent of the absorbed dose 3 h after the exposure.


Assuntos
Biomarcadores/metabolismo , Radiação Ionizante , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biomarcadores/sangue , Contagem de Células Sanguíneas , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Exposição à Radiação , Radiometria
13.
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
14.
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
15.
Nat Rev Cancer ; 20(9): 533-549, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32472073

RESUMO

Cell division and organismal development are exquisitely orchestrated and regulated processes. The dysregulation of the molecular mechanisms underlying these processes may cause cancer, a consequence of cell-intrinsic and/or cell-extrinsic events. Cellular DNA can be damaged by spontaneous hydrolysis, reactive oxygen species, aberrant cellular metabolism or other perturbations that cause DNA damage. Moreover, several environmental factors may damage the DNA, alter cellular metabolism or affect the ability of cells to interact with their microenvironment. While some environmental factors are well established as carcinogens, there remains a large knowledge gap of others owing to the difficulty in identifying them because of the typically long interval between carcinogen exposure and cancer diagnosis. DNA damage increases in cells harbouring mutations that impair their ability to correctly repair the DNA. Tumour predisposition syndromes in which cancers arise at an accelerated rate and in different organs - the equivalent of a sensitized background - provide a unique opportunity to examine how gene-environment interactions influence cancer risk when the initiating genetic defect responsible for malignancy is known. Understanding the molecular processes that are altered by specific germline mutations, environmental exposures and related mechanisms that promote cancer will allow the design of novel and effective preventive and therapeutic strategies.


Assuntos
Interação Gene-Ambiente , Predisposição Genética para Doença , Neoplasias/genética , Animais , Mutação em Linhagem Germinativa , Humanos
16.
Int J Mol Sci ; 20(22)2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31744230

RESUMO

Skin cancer is the most common type of cancer worldwide. Ozone depletion and climate changes might cause a further increase in the incidence rate in the future. Although the early detection of skin cancer enables it to be treated successfully, some tumours can evolve and become more aggressive, especially in the case of melanoma. Therefore, good diagnostic and prognostic markers are needed to ensure correct detection and treatment. Transcription factor p63, a member of the p53 family of proteins, plays an essential role in the development of stratified epithelia such as skin. In this paper, we conduct a comprehensive review of p63 expression in different types of skin cancer and discuss its possible use in the diagnosis and prognosis of cutaneous tumours.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Basocelular/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Carcinoma Basocelular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Humanos , Imuno-Histoquímica , Melanoma/metabolismo , Prognóstico , Neoplasias Cutâneas/metabolismo
17.
Biotechnol J ; 14(3): e1800081, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29975457

RESUMO

Hairy root (HR) cultures represent an attractive platform for the production of heterologous proteins, due to the possibility of secreting the molecule of interest in the culture medium. The main limitation is the low accumulation yields of heterologous proteins. The aim of this study is to enhance the accumulation of a tumor-targeting antibody with a human-compatible glycosylation profile in HR culture medium. To this aim, the authors produce Nicotiana benthamiana HR cultures expressing the red fluorescent protein (RFP) to easily screen for different auxins able to induce heterologous protein secretion in the medium. The hormone 2,4-dichlorophenoxyacetic acid (2,4-D) is found to induce high accumulation levels (334 mg L-1 ) of RFP in the culture medium. The same protocol is used to improve the secretion of the tumor-targeting, CD20-specific 2B8-FcΔXF recombinant antibody from glyco-engineered ΔXTFT N. benthamiana HR cultures. The addition of 2,4-D determine a 28-fold increase of the accumulation of fully functional 2B8-FcΔXF in the culture medium, at levels of ≈16 mg L-1 . Antibody N-glycosylation profiling reveal the prominent occurrence of GnGn structures and low levels of xylose- and fucose-containing counterparts. This result is the first example of the expression of an engineered anti-CD20 antibody with a scFv-Fc format at high levels in HR.


Assuntos
Anticorpos Monoclonais/genética , Nicotiana/genética , Raízes de Plantas/genética , Anticorpos de Cadeia Única/genética , Antígenos CD20/genética , Fucose/genética , Glicosilação , Humanos , Proteínas Luminescentes/genética , Plantas Geneticamente Modificadas/genética , Engenharia de Proteínas/métodos , Proteínas Recombinantes/genética , Xilose/genética , Proteína Vermelha Fluorescente
18.
Biotechnol Bioeng ; 115(3): 565-576, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29178403

RESUMO

Anti-CD20 recombinant antibodies are among the most promising therapeutics for the treatment of B-cell malignancies such as non-Hodgkin lymphomas. We recently demonstrated that an immunocytokine (2B8-Fc-hIL2), obtained by fusing an anti-CD20 scFv-Fc antibody derived from C2B8 mAb (rituximab) to the human interleukin 2 (hIL-2), can be efficiently produced in Nicotiana benthamiana plants. The purified immunocytokine (IC) bearing a typical plant protein N-glycosylation profile showed a CD20 binding activity comparable to that of rituximab and was efficient in eliciting antibody-dependent cell-mediated cytotoxicity (ADCC) of human PBMC against Daudi cells, indicating its fuctional integrity. In this work, the immunocytokine devoid of the typical xylose/fucose N-glycosylation plant signature (IC-ΔXF) and the corresponding scFv-Fc-ΔXF antibody not fused to the cytokine, were obtained in a glyco-engineered ΔXylT/FucT N. benthamiana line. Purification yields from agroinfiltrated plants amounted to 20-35 mg/kg of leaf fresh weight. When assayed for interaction with FcγRI and FcγRIIIa, IC-ΔXF exhibited significantly enhanced binding affinities if compared to the counterpart bearing the typical plant protein N-glycosylation profile (IC) and to rituximab. The glyco-engineered recombinant molecules also exhibited a strongly improved ADCC and complement-dependent cytotoxicity (CDC). Notably, our results demonstrate a reduced C1q binding of xylose/fucose carrying IC and scFv-Fc compared to versions that lack these sugar moieties. These results demonstrate that specific N-glycosylation alterations in recombinant products can dramatically affect the effector functions of the immunocytokine, resulting in an overall improvement of the biological functions and consequently of the therapeutic potential.


Assuntos
Interleucina-2 , Leucócitos Mononucleares/metabolismo , Nicotiana , Plantas Geneticamente Modificadas , Polissacarídeos , Proteínas Recombinantes de Fusão , Anticorpos de Cadeia Única , Humanos , Interleucina-2/biossíntese , Interleucina-2/química , Interleucina-2/genética , Interleucina-2/farmacologia , Leucócitos Mononucleares/citologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Polissacarídeos/biossíntese , Polissacarídeos/genética , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Engenharia de Proteínas , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Anticorpos de Cadeia Única/biossíntese , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/isolamento & purificação , Anticorpos de Cadeia Única/farmacologia , Nicotiana/genética , Nicotiana/metabolismo
19.
Cell Death Discov ; 3: 17071, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29152378

RESUMO

Zinc-finger proteins (ZNFs) are one of the most abundant groups of proteins and have a wide range of molecular functions. Given the wide variety of zinc-finger domains, ZNFs are able to interact with DNA, RNA, PAR (poly-ADP-ribose) and other proteins. Thus, ZNFs are involved in the regulation of several cellular processes. In fact, ZNFs are implicated in transcriptional regulation, ubiquitin-mediated protein degradation, signal transduction, actin targeting, DNA repair, cell migration, and numerous other processes. The aim of this review is to provide a comprehensive summary of the current state of knowledge of this class of proteins. Firstly, we describe the actual classification of ZNFs, their structure and functions. Secondly, we focus on the biological role of ZNFs in the development of organisms under normal physiological and pathological conditions.

20.
Biochem Biophys Res Commun ; 482(3): 440-444, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28212728

RESUMO

The transcription factor p63 belongs to the p53-family and is a master regulator of proliferative potential, lineage specification, and differentiation in epithelia during development and tissue homeostasis. In cancer, p63 contribution is isoform-specific, with both oncogenic and tumour suppressive roles attributed, for ΔNp63 and TAp63, respectively. Recently, p53 and TAp73, in line with other tumour suppressor genes, have emerged as important regulators of energy metabolism and metabolic reprogramming in cancer. To date, p63 contributions in controlling energy metabolism have been partially investigated; given the extensive interaction of the p53 family members, these studies have potential implications in tumour cells for metabolic reprogramming. Here, we review the role of p63 isoforms, TAp63 and ΔNp63, in controlling cell metabolism, focusing on their specific metabolic target genes and their physiological/functional context of action.


Assuntos
Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Antioxidantes/metabolismo , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos , Redes e Vias Metabólicas , Neoplasias/etiologia , Neoplasias/metabolismo , Isoformas de Proteínas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA