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1.
J Proteome Res ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39447324

RESUMO

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) started with spatial mapping of peptides and proteins. Since then, numerous bottom-up protocols have been developed. However, achievable spatial resolution and sample preparation with many wet steps hindered the development of single cell-level workflows for bottom-up spatial proteomics. This study presents a protocol optimized for MALDI-MSI measurements of single cells within the context of their 2D culture. Sublimation of CHCA, followed by a dip in ice-cold ammonium phosphate monobasic (AmP), produced peptide-rich mass spectra while maintaining matrix crystal sizes around 400 nm. This enables MALDI-MSI imaging of proteins in single cells grown on an ITO slide with a throughput of approximately 7800 cells per day. 89 peptide-like features corresponding to a single MDA-MB-231 breast cancer cell were detected. Furthermore, by combining the MALDI-MSI data with LC-MS/MS data obtained on cell pellets, we have successfully identified 24 peptides corresponding to 17 proteins, including actin, vimentin, and transgelin-2.

2.
Br J Cancer ; 130(4): 568-584, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38160212

RESUMO

BACKGROUND: Lung cancer is the most lethal cancer, and 85% of cases are classified as non-small cell lung cancer (NSCLC). Metabolic rewiring is a cancer hallmark that causes treatment resistance, and lacks insights into serine/glycine pathway adaptations upon radiotherapy. METHODS: We analyzed radiotherapy responses using mass-spectrometry-based metabolomics in NSCLC patient's plasma and cell lines. Efficacy of serine/glycine conversion inhibitor sertraline with radiotherapy was investigated by proliferation, clonogenic and spheroid assays, and in vivo using a serine/glycine dependent NSCLC mouse model by assessment of tumor growth, metabolite and cytokine levels, and immune signatures. RESULTS: Serine/glycine pathway metabolites were significantly consumed in response to radiotherapy in NSCLC patients and cell models. Combining sertraline with radiotherapy impaired NSCLC proliferation, clonogenicity and stem cell self-renewal capacity. In vivo, NSCLC tumor growth was reduced solely in the sertraline plus radiotherapy combination treatment group. Tumor weights linked to systemic serine/glycine pathway metabolite levels, and were inhibited in the combination therapy group. Interestingly, combination therapy reshaped the tumor microenvironment via cytokines associated with natural killer cells, supported by eradication of immune checkpoint galectin-1 and elevated granzyme B levels. CONCLUSION: Our findings highlight that targeting serine/glycine metabolism using sertraline restricts cancer cell recovery from radiotherapy and provides tumor control through immunomodulation in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Camundongos , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/metabolismo , Serina , Sertralina , Linhagem Celular Tumoral , Glicina , Microambiente Tumoral
3.
Microb Cell Fact ; 23(1): 119, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659027

RESUMO

BACKGROUND: Clostridium spp. has demonstrated therapeutic potential in cancer treatment through intravenous or intratumoral administration. This approach has expanded to include non-pathogenic clostridia for the treatment of various diseases, underscoring the innovative concept of oral-spore vaccination using clostridia. Recent advancements in the field of synthetic biology have significantly enhanced the development of Clostridium-based bio-therapeutics. These advancements are particularly notable in the areas of efficient protein overexpression and secretion, which are crucial for the feasibility of oral vaccination strategies. Here, we present two examples of genetically engineered Clostridium candidates: one as an oral cancer vaccine and the other as an antiviral oral vaccine against SARS-CoV-2. RESULTS: Using five validated promoters and a signal peptide derived from Clostridium sporogenes, a series of full-length NY-ESO-1/CTAG1, a promising cancer vaccine candidate, expression vectors were constructed and transformed into C. sporogenes and Clostridium butyricum. Western blotting analysis confirmed efficient expression and secretion of NY-ESO-1 in clostridia, with specific promoters leading to enhanced detection signals. Additionally, the fusion of a reported bacterial adjuvant to NY-ESO-1 for improved immune recognition led to the cloning difficulties in E. coli. The use of an AUU start codon successfully mitigated potential toxicity issues in E. coli, enabling the secretion of recombinant proteins in C. sporogenes and C. butyricum. We further demonstrate the successful replacement of PyrE loci with high-expression cassettes carrying NY-ESO-1 and adjuvant-fused NY-ESO-1, achieving plasmid-free clostridia capable of secreting the antigens. Lastly, the study successfully extends its multiplex genetic manipulations to engineer clostridia for the secretion of SARS-CoV-2-related Spike_S1 antigens. CONCLUSIONS: This study successfully demonstrated that C. butyricum and C. sporogenes can produce the two recombinant antigen proteins (NY-ESO-1 and SARS-CoV-2-related Spike_S1 antigens) through genetic manipulations, utilizing the AUU start codon. This approach overcomes challenges in cloning difficult proteins in E. coli. These findings underscore the feasibility of harnessing commensal clostridia for antigen protein secretion, emphasizing the applicability of non-canonical translation initiation across diverse species with broad implications for medical or industrial biotechnology.


Assuntos
Clostridium butyricum , Clostridium , Proteínas Recombinantes , Clostridium butyricum/genética , Clostridium butyricum/metabolismo , Clostridium/genética , Clostridium/metabolismo , Humanos , Proteínas Recombinantes/genética , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/genética , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/genética , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Administração Oral , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Esporos Bacterianos/genética , Esporos Bacterianos/imunologia , Vacinação , COVID-19/prevenção & controle , Engenharia Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Regiões Promotoras Genéticas
4.
Int J Mol Sci ; 25(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39000386

RESUMO

Cholangiocarcinoma (CCA), or bile duct cancer, is the second most common liver malignancy, with an increasing incidence in Western countries. The lack of effective treatments associated with the absence of early symptoms highlights the need to search for new therapeutic targets for CCA. Sulfatides (STs), a type of sulfoglycosphingolipids, have been found in the biliary tract, with increased levels in CCA and other types of cancer. STs are involved in protein trafficking and cell adhesion as part of the lipid rafts of the plasma membrane. We aimed to study the role of STs in CCA by the genetic targeting of GAL3ST1, an enzyme involved in ST synthesis. We used the CRISPR-Cas9 system to generate GAL3ST1-deficient TFK1 cells. GAL3ST1 KO cells showed lower proliferation and clonogenic activity and reduced glycolytic activity compared to TFK1 cells. Polarized TFK1 GAL3ST1 KO cells displayed increased transepithelial resistance and reduced permeability compared to TFK1 wt cells. The loss of GAL3ST1 showed a negative effect on growth in 30 out of 34 biliary tract cancer cell lines from the DepMap database. GAL3ST1 deficiency partially restored epithelial identity and barrier function and reduced proliferative activity in CCA cells. Sulfatide synthesis may provide a novel therapeutic target for CCA.


Assuntos
Neoplasias dos Ductos Biliares , Proliferação de Células , Colangiocarcinoma , Transição Epitelial-Mesenquimal , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Colangiocarcinoma/genética , Humanos , Transição Epitelial-Mesenquimal/genética , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/genética , Linhagem Celular Tumoral , Sulfotransferases/metabolismo , Sulfotransferases/genética , Sulfotransferases/deficiência , Sulfoglicoesfingolipídeos/metabolismo , Sistemas CRISPR-Cas , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia
5.
Int J Mol Sci ; 24(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36835181

RESUMO

Radiotherapy (RT) is a key player in the treatment of head and neck cancer (HNC). The RT response, however, is variable and influenced by multiple tumoral and tumor microenvironmental factors, such as human papillomavirus (HPV) infections and hypoxia. To investigate the biological mechanisms behind these variable responses, preclinical models are crucial. Up till now, 2D clonogenic and in vivo assays have remained the gold standard, although the popularity of 3D models is rising. In this study, we investigate the use of 3D spheroid models as a preclinical tool for radiobiological research by comparing the RT response of two HPV-positive and two HPV-negative HNC spheroid models to the RT response of their corresponding 2D and in vivo models. We demonstrate that HPV-positive spheroids keep their higher intrinsic radiosensitivity when compared to HPV-negative spheroids. A good correlation is found in the RT response between HPV-positive SCC154 and HPV-negative CAL27 spheroids and their respective xenografts. In addition, 3D spheroids are able to capture the heterogeneity of RT responses within HPV-positive and HPV-negative models. Moreover, we demonstrate the potential use of 3D spheroids in the study of the mechanisms underlying these RT responses in a spatial manner by whole-mount Ki-67 and pimonidazole staining. Overall, our results show that 3D spheroids are a promising model to assess the RT response in HNC.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Tolerância a Radiação
6.
PLoS Comput Biol ; 16(8): e1008041, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745136

RESUMO

Hypoxia-activated prodrugs (HAPs) present a conceptually elegant approach to not only overcome, but better yet, exploit intra-tumoural hypoxia. Despite being successful in vitro and in vivo, HAPs are yet to achieve successful results in clinical settings. It has been hypothesised that this lack of clinical success can, in part, be explained by the insufficiently stringent clinical screening selection of determining which tumours are suitable for HAP treatments. Taking a mathematical modelling approach, we investigate how tumour properties and HAP-radiation scheduling influence treatment outcomes in simulated tumours. The following key results are demonstrated in silico: (i) HAP and ionising radiation (IR) monotherapies may attack tumours in dissimilar, and complementary, ways. (ii) HAP-IR scheduling may impact treatment efficacy. (iii) HAPs may function as IR treatment intensifiers. (iv) The spatio-temporal intra-tumoural oxygen landscape may impact HAP efficacy. Our in silico framework is based on an on-lattice, hybrid, multiscale cellular automaton spanning three spatial dimensions. The mathematical model for tumour spheroid growth is parameterised by multicellular tumour spheroid (MCTS) data.


Assuntos
Antineoplásicos/farmacologia , Hipóxia Celular/fisiologia , Modelos Biológicos , Pró-Fármacos/farmacologia , Microambiente Tumoral/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Biologia Computacional , Simulação por Computador , Humanos , Radiação Ionizante , Radioterapia , Esferoides Celulares , Células Tumorais Cultivadas
7.
BMC Cancer ; 20(1): 557, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539805

RESUMO

BACKGROUND: About 50% of non-small cell lung cancer (NSCLC) patients have metastatic disease at initial diagnosis, which limits their treatment options and, consequently, the 5-year survival rate (15%). Immune checkpoint inhibitors (ICI), either alone or in combination with chemotherapy, have become standard of care (SOC) for most good performance status patients. However, most patients will not obtain long-term benefit and new treatment strategies are therefore needed. We previously demonstrated clinical safety of the tumour-selective immunocytokine L19-IL2, consisting of the anti-ED-B scFv L19 antibody coupled to IL2, combined with stereotactic ablative radiotherapy (SABR). METHODS: This investigator-initiated, multicentric, randomised controlled open-label phase II clinical trial will test the hypothesis that the combination of SABR and L19-IL2 increases progression free survival (PFS) in patients with limited metastatic NSCLC. One hundred twenty-six patients will be stratified according to their metastatic load (oligo-metastatic: ≤5 or poly-metastatic: 6 to 10) and randomised to the experimental-arm (E-arm) or the control-arm (C-arm). The C-arm will receive SOC, according to the local protocol. E-arm oligo-metastatic patients will receive SABR to all lesions followed by L19-IL2 therapy; radiotherapy for poly-metastatic patients consists of irradiation of one (symptomatic) to a maximum of 5 lesions (including ICI in both arms if this is the SOC). The accrual period will be 2.5-years, starting after the first centre is initiated and active. Primary endpoint is PFS at 1.5-years based on blinded radiological review, and secondary endpoints are overall survival, toxicity, quality of life and abscopal response. Associative biomarker studies, immune monitoring, CT-based radiomics, stool collection, iRECIST and tumour growth rate will be performed. DISCUSSION: The combination of SABR with or without ICI and the immunocytokine L19-IL2 will be tested as 1st, 2nd or 3rd line treatment in stage IV NSCLC patients in 14 centres located in 6 countries. This bimodal and trimodal treatment approach is based on the direct cytotoxic effect of radiotherapy, the tumour selective immunocytokine L19-IL2, the abscopal effect observed distant from the irradiated metastatic site(s) and the memory effect. The first results are expected end 2023. TRIAL REGISTRATION: ImmunoSABR Protocol Code: NL67629.068.18; EudraCT: 2018-002583-11; Clinicaltrials.gov: NCT03705403; ISRCTN ID: ISRCTN49817477; Date of registration: 03-April-2019.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia/métodos , Neoplasias Pulmonares/terapia , Radiocirurgia/métodos , Proteínas Recombinantes de Fusão/administração & dosagem , Adulto , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/secundário , Quimiorradioterapia/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Intervalo Livre de Progressão , Qualidade de Vida , Radiocirurgia/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Recombinantes de Fusão/efeitos adversos , Critérios de Avaliação de Resposta em Tumores Sólidos , Padrão de Cuidado
9.
Eur Heart J ; 37(39): 2993-2997, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27125949

RESUMO

AIMS: Normalization of hypercholesterolaemia, inflammation, hyperglycaemia, and obesity are main desired targets to prevent cardiovascular clinical events. Here we present a novel regulator of cholesterol metabolism, which simultaneously impacts on glucose intolerance and inflammation. METHODS AND RESULTS: Mice deficient for oxygen sensor HIF-prolyl hydroxylase 1 (PHD1) were backcrossed onto an atherogenic low-density lipoprotein receptor (LDLR) knockout background and atherosclerosis was studied upon 8 weeks of western-type diet. PHD1-/-LDLR-/- mice presented a sharp reduction in VLDL and LDL plasma cholesterol levels. In line, atherosclerotic plaque development, as measured by plaque area, necrotic core expansion and plaque stage was hampered in PHD1-/-LDLR-/- mice. Mechanistically, cholesterol-lowering in PHD1 deficient mice was a result of enhanced cholesterol excretion from blood to intestines and ultimately faeces. Additionally, flow cytometry of whole blood of these mice revealed significantly reduced counts of leucocytes and particularly of Ly6Chigh pro-inflammatory monocytes. In addition, when studying PHD1-/- in diet-induced obesity (14 weeks high-fat diet) mice were less glucose intolerant when compared with WT littermate controls. CONCLUSION: Overall, PHD1 knockout mice display a metabolic phenotype that generally is deemed protective for cardiovascular disease. Future studies should focus on the efficacy, safety, and gender-specific effects of PHD1 inhibition in humans, and unravel the molecular actors responsible for PHD1-driven, likely intestinal, and regulation of cholesterol metabolism.


Assuntos
Aterosclerose , Hipercolesterolemia , Hiperglicemia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigênio , Prolil Hidroxilases , Receptores de LDL
10.
Angew Chem Int Ed Engl ; 56(25): 7146-7150, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28493648

RESUMO

Mass spectrometry imaging (MSI) simultaneously detects and identifies the spatial distribution of numerous molecules throughout tissues. Currently, MSI is limited to providing a static and ex vivo snapshot of highly dynamic systems in which molecules are constantly synthesized and consumed. Herein, we demonstrate an innovative MSI methodology to study dynamic molecular changes of amino acids within biological tissues by measuring the dilution and conversion of stable isotopes in a mouse model. We evaluate the method specifically on hepatocellular metabolism of the essential amino acid l-phenylalanine, associated with liver diseases. Crucially, the method reveals the localized dynamics of l-phenylalanine metabolism, including its in vivo hydroxylation to l-tyrosine and co-localization with other liver metabolites in a time course of samples from different animals. This method thus enables the dynamics of localized biochemical synthesis to be studied directly from biological tissues.


Assuntos
Isótopos de Carbono/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Espectrometria de Massas/métodos , Fenilalanina/metabolismo , Tirosina/metabolismo , Animais , Modelos Animais de Doenças , Cromatografia Gasosa-Espectrometria de Massas/métodos , Xenoenxertos , Hidroxilação , Cinética , Camundongos , Camundongos Nus , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem/métodos
11.
BMC Cancer ; 16: 644, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27535748

RESUMO

BACKGROUND: Neo-adjuvant chemoradiotherapy followed by surgery is the standard treatment with curative intent for oesophageal cancer patients, with 5-year overall survival rates up to 50 %. However, patients' quality of life is severely compromised by oesophagectomy, and eventually many patients die due to metastatic disease. Most solid tumours, including oesophageal cancer, contain hypoxic regions that are more resistant to chemoradiotherapy. The hypoxia-activated prodrug evofosfamide works as a DNA-alkylating agent under these hypoxic conditions, which directly kills hypoxic cancer cells and potentially minimizes resistance to conventional therapy. This drug has shown promising results in several clinical studies when combined with chemotherapy. Therefore, in this phase I study we investigate the safety of evofosfamide added to the chemoradiotherapy treatment of oesophageal cancer. METHODS/DESIGN: A phase I, non-randomized, single-centre, open-label, 3 + 3 trial with repeated hypoxia PET imaging, will test the safety of evofosfamide in combination with neo-adjuvant chemoradiotherapy in potentially resectable oesophageal adenocarcinoma patients. Investigated dose levels range from 120 mg/m2 to 340 mg/m2. Evofosfamide will be administered one week before the start of chemoradiotherapy (CROSS-regimen) and repeated weekly up to a total of six doses. PET/CT acquisitions with hypoxia tracer (18)F-HX4 will be made before and after the first administration of evofosfamide, allowing early assessment of changes in hypoxia, accompanied with blood sampling to measure hypoxia blood biomarkers. Oesophagectomy will be performed according to standard clinical practice. Higher grade and uncommon non-haematological, haematological, and post-operative toxicities are the primary endpoints according to the CTCAEv4.0 and Clavien-Dindo classifications. Secondary endpoints are reduction in hypoxic fraction based on (18)F-HX4 imaging, pathological complete response, histopathological negative circumferential resection margin (R0) rate, local and distant recurrence rate, and progression free and overall survival. DISCUSSION: This is the first clinical trial testing evofosfamide in combination with chemoradiotherapy. The primary objective is to determine the dose limiting toxicity of this combined treatment and herewith to define the maximum tolerated dose and recommended phase 2 dose for future clinical studies. The addition of non-invasive repeated hypoxia imaging ('window-of-opportunity') enables us to identify the biologically effective dose. We believe this approach could also be used for other hypoxia targeted drugs. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02598687 .


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/terapia , Quimiorradioterapia Adjuvante/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Nitroimidazóis/administração & dosagem , Mostardas de Fosforamida/administração & dosagem , Hipóxia Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Esofagectomia , Feminino , Humanos , Masculino , Nitroimidazóis/farmacologia , Mostardas de Fosforamida/farmacologia , Tomografia por Emissão de Pósitrons/métodos , Cuidados Pré-Operatórios , Análise de Sobrevida , Resultado do Tratamento
12.
Proc Natl Acad Sci U S A ; 110(12): 4622-7, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23471998

RESUMO

Hypoxia is a common feature of tumors and an important contributor to malignancy and treatment resistance. The ability of tumor cells to survive hypoxic stress is mediated in part by hypoxia-inducible factor (HIF)-dependent transcriptional responses. More severe hypoxia activates endoplasmatic reticulum stress responses, including the double-stranded RNA-activated protein kinase (PKR)-like endoplasmic reticulum kinase (PERK)/eukaryotic initiation factor 2α (eIF2α)-dependent arm of the unfolded protein response (UPR). Although several studies implicate important roles for HIF and UPR in adaption to hypoxia, their importance for hypoxic cells responsible for therapy resistance in tumors is unknown. By using isogenic models, we find that HIF and eIF2α signaling contribute to the survival of hypoxic cells in vitro and in vivo. However, the eIF2α-dependent arm of the UPR is uniquely required for the survival of a subset of hypoxic cells that determine tumor radioresistance. We demonstrate that eIF2α signaling induces uptake of cysteine, glutathione synthesis, and protection against reactive oxygen species produced during periods of cycling hypoxia. Together these data imply that eIF2α signaling is a critical contributor to the tolerance of therapy-resistant cells that arise as a consequence of transient changes in oxygenation in solid tumors and thus a therapeutic target in curative treatments for solid cancers.


Assuntos
Fator de Iniciação 2 em Eucariotos/metabolismo , Glutationa/biossíntese , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Resposta a Proteínas não Dobradas , eIF-2 Quinase/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Hipóxia Celular/genética , Linhagem Celular Tumoral , Fator de Iniciação 2 em Eucariotos/genética , Glutationa/genética , Humanos , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Neoplasias/genética , Neoplasias/terapia , Transdução de Sinais/genética , Transplante Heterólogo , eIF-2 Quinase/genética
13.
Arterioscler Thromb Vasc Biol ; 34(12): 2545-53, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25256233

RESUMO

OBJECTIVE: Advanced murine and human plaques are hypoxic, but it remains unclear whether plaque hypoxia is causally related to atherogenesis. Here, we test the hypothesis that reversal of hypoxia in atherosclerotic plaques by breathing hyperoxic carbogen gas will prevent atherosclerosis. APPROACH AND RESULTS: Low-density lipoprotein receptor-deficient mice (LDLR(-/-)) were fed a Western-type diet, exposed to carbogen (95% O2, 5% CO2) or air, and the effect on plaque hypoxia, size, and phenotype was studied. First, the hypoxic marker pimonidazole was detected in murine LDLR(-/-) plaque macrophages from plaque initiation onwards. Second, the efficacy of breathing carbogen (90 minutes, single exposure) was studied. Compared with air, carbogen increased arterial blood pO2 5-fold in LDLR(-/-) mice and reduced plaque hypoxia in advanced plaques of the aortic root (-32%) and arch (-84%). Finally, the effect of repeated carbogen exposure on progression of atherosclerosis was studied in LDLR(-/-) mice fed a Western-type diet for an initial 4 weeks, followed by 4 weeks of diet and carbogen or air (both 90 min/d). Carbogen reduced plaque hypoxia (-40%), necrotic core size (-37%), and TUNEL(+) (terminal uridine nick-end labeling positive) apoptotic cell content (-50%) and increased efferocytosis of apoptotic cells by cluster of differentiation 107b(+) (CD107b, MAC3) macrophages (+36%) in advanced plaques of the aortic root. Plaque size, plasma cholesterol, hematopoiesis, and systemic inflammation were unchanged. In vitro, hypoxia hampered efferocytosis by bone marrow-derived macrophages, which was dependent on the receptor Mer tyrosine kinase. CONCLUSIONS: Carbogen restored murine plaque oxygenation and prevented necrotic core expansion by enhancing efferocytosis, likely via Mer tyrosine kinase. Thus, plaque hypoxia is causally related to necrotic core expansion.


Assuntos
Hipóxia/patologia , Placa Aterosclerótica/patologia , Placa Aterosclerótica/prevenção & controle , Animais , Apoptose , Antígenos CD36/deficiência , Antígenos CD36/genética , Dióxido de Carbono/administração & dosagem , Humanos , Hipóxia/fisiopatologia , Hipóxia/terapia , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Necrose , Oxigênio/administração & dosagem , Oxigênio/sangue , Fagocitose , Placa Aterosclerótica/fisiopatologia , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Proteína Tirosina Quinases/deficiência , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de LDL/deficiência , Receptores de LDL/genética , c-Mer Tirosina Quinase
14.
BMC Cancer ; 14: 130, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24571588

RESUMO

BACKGROUND: Quantification of molecular cell processes is important for prognostication and treatment individualization of head and neck cancer (HNC). However, individual tumor comparison can show discord in upregulation similarities when analyzing multiple biological mechanisms. Elaborate tumor characterization, integrating multiple pathways reflecting intrinsic and microenvironmental properties, may be beneficial to group most uniform tumors for treatment modification schemes. The goal of this study was to systematically analyze if immunohistochemical (IHC) assessment of molecular markers, involved in treatment resistance, and 18F-FDG PET parameters could accurately distinguish separate HNC tumors. METHODS: Several imaging parameters and texture features for 18F-FDG small-animal PET and immunohistochemical markers related to metabolism, hypoxia, proliferation and tumor blood perfusion were assessed within groups of BALB/c nu/nu mice xenografted with 14 human HNC models. Classification methods were used to predict tumor line based on sets of parameters. RESULTS: We found that 18F-FDG PET could not differentiate between the tumor lines. On the contrary, combined IHC parameters could accurately allocate individual tumors to the correct model. From 9 analyzed IHC parameters, a cluster of 6 random parameters already classified 70.3% correctly. Combining all PET/IHC characteristics resulted in the highest tumor line classification accuracy (81.0%; cross validation 82.0%), which was just 2.2% higher (p = 5.2×10-32) than the performance of the IHC parameter/feature based model. CONCLUSIONS: With a select set of IHC markers representing cellular processes of metabolism, proliferation, hypoxia and perfusion, one can reliably distinguish between HNC tumor lines. Addition of 18F-FDG PET improves classification accuracy of IHC to a significant yet minor degree. These results may form a basis for development of tumor characterization models for treatment allocation purposes.


Assuntos
Biomarcadores Tumorais/metabolismo , Proliferação de Células , Fluordesoxiglucose F18/metabolismo , Neoplasias de Cabeça e Pescoço/classificação , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Animais , Biomarcadores Tumorais/biossíntese , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Proc Natl Acad Sci U S A ; 108(35): 14620-5, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21873245

RESUMO

Hypoxia has been shown to be an important microenvironmental parameter influencing tumor progression and treatment efficacy. Patient guidance for hypoxia-targeted therapy requires evaluation of tumor oxygenation, preferably in a noninvasive manner. The aim of this study was to evaluate and validate the uptake of [(18)F]HX4, a novel developed hypoxia marker for PET imaging. A heterogeneous accumulation of [(18)F]HX4 was found within rat rhabdomyosarcoma tumors that was significantly (P < 0.0001) higher compared with the surrounding tissues, with temporal increasing tumor-to-blood ratios reaching a plateau of 7.638 ± 0.926 and optimal imaging properties 4 h after injection. [(18)F]HX4 retention in normal tissues was found to be short-lived, homogeneous and characterized by a fast progressive temporal clearance. Heterogeneity in [(18)F]HX4 tumor uptake was analyzed based on 16 regions within the tumor according to the different orthogonal planes at the largest diameter. Validation of heterogeneous [(18)F]HX4 tumor uptake was shown by a strong and significant relationship (r = 0.722; P < 0.0001) with the hypoxic fraction as calculated by the percentage pimonidazole-positive pixels. Furthermore, a causal relationship with tumor oxygenation was established, because combination treatment of nicotinamide and carbogen resulted in a 40% reduction (P < 0.001) in [(18)F]HX4 tumor accumulation whereas treatment with 7% oxygen breathing resulted in a 30% increased uptake (P < 0.05). [(18)F]HX4 is therefore a promising candidate for noninvasive detection and evaluation of tumor hypoxia at a macroscopic level.


Assuntos
Hipóxia Celular , Radioisótopos de Flúor , Imidazóis , Neoplasias Experimentais/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Triazóis , Animais , Biomarcadores , Masculino , Nitroimidazóis/farmacologia , Ratos
16.
Cancers (Basel) ; 16(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38254860

RESUMO

The discovery of the distinctive structure of heavy chain-only antibodies in species belonging to the Camelidae family has elicited significant interest in their variable antigen binding domain (VHH) and gained attention for various applications, such as cancer diagnosis and treatment. This article presents an overview of the characteristics, advantages, and disadvantages of VHHs as compared to conventional antibodies, and their usage in diverse applications. The singular properties of VHHs are explained, and several strategies that can augment their utility are outlined. The preclinical studies illustrating the diagnostic and therapeutic efficacy of distinct VHHs in diverse formats against solid cancers are summarized, and an overview of the clinical trials assessing VHH-based agents in oncology is provided. These investigations demonstrate the enormous potential of VHHs for medical research and healthcare.

17.
Microbiol Res ; 288: 127889, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39217797

RESUMO

Clostridium butyricum has emerged as a promising candidate for both industrial and medical biotechnologies, underscoring the key pursuit of stable gene overexpression in engineering C. butyricum. Unlike antibiotic-selective vectors, native-cryptic plasmids can be utilized for antibiotic-free expression systems in bacteria but have not been effectively exploited in C. butyricum to date. This study focuses on leveraging these plasmids, pCB101 and pCB102, in C. butyricum DSM10702 for stable gene overexpression without antibiotic selection via efficient gene integration using the SacB-based allelic exchange method. Integration of reporter IFP2.0 and glucuronidase generated sustained near-infrared fluorescence and robust enzyme activity across successive subcultures. Furthermore, successful secretion of a cellulase, Cel9M, and the human interleukin 10 from pCB102 highlights native-cryptic plasmids' potential in conferring stable gene products for industrial and medical applications in C. butyricum. This work appears to be the first study to harness the Clostridium native-cryptic plasmid for stable gene overexpression without antibiotics, thereby advancing the biotechnological prospects of C. butyricum.


Assuntos
Clostridium butyricum , Plasmídeos , Clostridium butyricum/genética , Plasmídeos/genética , Humanos , Expressão Gênica , Biotecnologia/métodos , Glucuronidase/genética , Glucuronidase/metabolismo , Celulase/genética , Celulase/metabolismo , Genes Reporter , Microbiologia Industrial/métodos , Regulação Bacteriana da Expressão Gênica , Vetores Genéticos
18.
Artigo em Inglês | MEDLINE | ID: mdl-38375937

RESUMO

CONTEXT: Abdominal obesity is associated with increased cardiometabolic disease risk, while lower body fat seems to confer protection against obesity-related complications. The functional differences between upper and lower body adipose tissue (AT) remain poorly understood. OBJECTIVE: We aimed to examine whether mitochondrial respiration is impaired in abdominal as compared to femoral differentiated human multipotent adipose-derived stem cells (hMADS; primary outcome) and AT in postmenopausal women. DESIGN: In this cross-sectional study, 23 postmenopausal women with normal weight or obesity were recruited at the University of Birmingham/Queen Elizabeth Hospital Birmingham (Birmingham, UK). We collected abdominal and femoral subcutaneous AT biopsies to determine mitochondrial oxygen consumption rates in differentiated abdominal and femoral hMADS. Furthermore, we assessed OXPHOS protein expression and mtDNA content in abdominal and femoral AT as well as hMADS. Finally, we explored in vivo fractional oxygen extraction and carbon dioxide release across abdominal and femoral subcutaneous AT in a subgroup of the same individuals with normal weight or obesity. RESULTS: We found lower basal and maximal uncoupled mitochondrial oxygen consumption rates in abdominal compared to femoral hMADS. In line, in vivo fractional oxygen extraction and carbon dioxide release were lower across abdominal than femoral AT. OXPHOS protein expression and mtDNA content did not significantly differ between abdominal and femoral differentiated hMADS and AT. CONCLUSION: The present findings demonstrate that in vitro mitochondrial respiration and in vivo oxygen fractional extraction are lower in upper compared to lower body differentiated hMADS and AT, respectively, in postmenopausal women.

19.
Cancers (Basel) ; 15(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37173877

RESUMO

Radiotherapy is one of the standard treatment approaches used against thoracic cancers, occasionally combined with chemotherapy, immunotherapy and molecular targeted therapy. However, these cancers are often not highly sensitive to standard of care treatments, making the use of high dose radiotherapy necessary, which is linked with high rates of radiation-induced adverse effects in healthy tissues of the thorax. These tissues remain therefore dose-limiting factors in radiation oncology despite recent technological advances in treatment planning and delivery of irradiation. Polyphenols are metabolites found in plants that have been suggested to improve the therapeutic window by sensitizing the tumor to radiotherapy, while simultaneously protecting normal cells from therapy-induced damage by preventing DNA damage, as well as having anti-oxidant, anti-inflammatory or immunomodulatory properties. This review focuses on the radioprotective effect of polyphenols and the molecular mechanisms underlying these effects in the normal tissue, especially in the lung, heart and esophagus.

20.
J Imaging ; 9(6)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37367472

RESUMO

Despite the intensive use of radiotherapy in clinical practice, its effectiveness depends on several factors. Several studies showed that the tumour response to radiation differs from one patient to another. The non-uniform response of the tumour is mainly caused by multiple interactions between the tumour microenvironment and healthy cells. To understand these interactions, five major biologic concepts called the "5 Rs" have emerged. These concepts include reoxygenation, DNA damage repair, cell cycle redistribution, cellular radiosensitivity and cellular repopulation. In this study, we used a multi-scale model, which included the five Rs of radiotherapy, to predict the effects of radiation on tumour growth. In this model, the oxygen level was varied in both time and space. When radiotherapy was given, the sensitivity of cells depending on their location in the cell cycle was taken in account. This model also considered the repair of cells by giving a different probability of survival after radiation for tumour and normal cells. Here, we developed four fractionation protocol schemes. We used simulated and positron emission tomography (PET) imaging with the hypoxia tracer 18F-flortanidazole (18F-HX4) images as input data of our model. In addition, tumour control probability curves were simulated. The result showed the evolution of tumours and normal cells. The increase in the cell number after radiation was seen in both normal and malignant cells, which proves that repopulation was included in this model. The proposed model predicts the tumour response to radiation and forms the basis for a more patient-specific clinical tool where related biological data will be included.

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