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1.
Am J Pathol ; 194(6): 1137-1153, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38749609

RESUMO

Preclinical models that display spontaneous metastasis are necessary to improve the therapeutic options for hormone receptor-positive breast cancers. Within this study, detailed cellular and molecular characterization was conducted on MCa-P1362, a newly established mouse model of metastatic breast cancer that is syngeneic in BALB/c mice. MCa-P1362 cancer cells express estrogen receptor, progesterone receptor, and the human epidermal growth factor receptor 2. MCa-P1362 cancer cells proliferate in vitro and in vivo in response to estrogen, yet do not depend on steroid hormones for growth and tumor progression. Analysis of MCa-P1362 tumor explants revealed the tumors contained a mixture of cancer cells and mesenchymal stromal cells. Through transcriptomic and functional analyses of both cancer and stromal cells, stem cells were detected within both populations. Functional studies demonstrated that MCa-P1362 cancer stem cells drove tumor initiation, whereas stromal cells from these tumors contributed to drug resistance. MCa-P1362 may serve as a useful preclinical model to investigate the cellular and molecular basis of breast tumor progression and therapeutic resistance.


Assuntos
Adenocarcinoma , Células-Tronco Mesenquimais , Camundongos Endogâmicos BALB C , Receptor ErbB-2 , Receptores de Estrogênio , Animais , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Feminino , Humanos , Receptor ErbB-2/metabolismo , Camundongos , Receptores de Estrogênio/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Linhagem Celular Tumoral , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/metabolismo
2.
Breast Cancer Res Treat ; 204(2): 327-340, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38127176

RESUMO

PURPOSE: Prior studies indicate that the physiologic response to stress can affect gene expression. We evaluated differential gene expression in breast cancers collected from Black women with high versus low exposure to psychosocial stressors. METHODS: We analyzed tumor RNA sequencing data from 417 Black Women's Health Study breast cancer cases with data on early life trauma and neighborhood disadvantage. We conducted age-adjusted differential gene expression analyses and pathway analyses. We also evaluated Conserved Transcriptional Response to Adversity (CTRA) contrast scores, relative fractions of immune cell types, T cell exhaustion, and adrenergic signaling. Analyses were run separately for estrogen receptor positive (ER+; n = 299) and ER- (n = 118) cases. RESULTS: Among ER+ cases, the top differentially expressed pathways by stress exposure were related to RNA and protein metabolism. Among ER- cases, they were related to developmental biology, signal transduction, metabolism, and the immune system. Targeted analyses indicated greater immune pathway enrichment with stress exposure for ER- cases, and possible relevance of adrenergic signaling for ER+ cases. CTRA contrast scores did not differ by stress exposure, but in analyses of the CTRA components, ER- breast cancer cases with high neighborhood disadvantage had higher pro-inflammatory gene expression (p = 0.039) and higher antibody gene expression (p = 0.006) compared to those with low neighborhood disadvantage. CONCLUSION: There are multiple pathways through which psychosocial stress exposure may influence breast tumor biology. Given the present findings on inflammation and immune response in ER- tumors, further research to identify stress-induced changes in the etiology and progression of ER- breast cancer is warranted.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Saúde da Mulher , Adrenérgicos , Expressão Gênica
3.
Am J Pathol ; 191(1): 4-17, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919977

RESUMO

The rapid spread of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), has resulted in an unprecedented public health crisis worldwide. Recent studies indicate that a hyperinflammatory syndrome induced by SARS-CoV-2 contributes to disease severity and mortality in COVID-19. In this review, an overview of the pathophysiology underlying the hyperinflammatory syndrome in severe COVID-19 is provided. The current evidence suggests that the hyperinflammatory syndrome results from a dysregulated host innate immune response. The gross and microscopic pathologic findings as well as the alterations in the cytokine milieu, macrophages/monocytes, natural killer cells, T cells, and neutrophils in severe COVID-19 are summarized. The data highlighted include the potential therapeutic approaches undergoing investigation to modulate the immune response and abrogate lung injury in severe COVID-19.


Assuntos
COVID-19/imunologia , Síndrome da Liberação de Citocina , Sistema Imunitário , Inflamação , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Corticosteroides/uso terapêutico , COVID-19/epidemiologia , COVID-19/terapia , Armadilhas Extracelulares , Humanos , Imunidade Inata , Células Matadoras Naturais/imunologia , Ativação de Macrófagos , Macrófagos/imunologia , Monócitos/imunologia , Neutrófilos/imunologia , Fagocitose , SARS-CoV-2/fisiologia , Linfócitos T/imunologia , Replicação Viral
4.
Am J Pathol ; 191(8): 1353-1363, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34043978

RESUMO

Breast cancer (BC) accounts for significant morbidity and mortality among women worldwide. About one in three patients with breast cancer present with lymph node (LN) metastasis and LN status is one of the most important prognostic predictors in patients with BC. In addition to their prognostic value, LNs initiate adaptive immunity against BC. Yet, BC cells often avoid immune-mediated destruction in LNs. This review provides an overview of the ways by which BC cells modulate LN stromal and hematopoietic cells to promote metastasis and immune evasion.


Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Metástase Linfática/imunologia , Metástase Linfática/patologia , Evasão Tumoral/imunologia , Feminino , Humanos
5.
Proc Natl Acad Sci U S A ; 116(6): 2210-2219, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30659155

RESUMO

In ovarian cancer patients, tumor fibrosis and angiotensin-driven fibrogenic signaling have been shown to inversely correlate with survival. We sought to enhance drug delivery and therapeutic efficacy by remodeling the dense extracellular matrix in two orthotopic human ovarian carcinoma xenograft models. We hypothesized that targeting the angiotensin signaling axis with losartan, an approved angiotensin system inhibitor, could reduce extracellular matrix content and the associated "solid stress," leading to better anticancer therapeutic effect. We report here four translatable findings: (i) losartan treatment enhances the efficacy of paclitaxel-a drug used for ovarian cancer treatment-via normalizing the tumor microenvironment, resulting in improved vessel perfusion and drug delivery; (ii) losartan depletes matrix via inducing antifibrotic miRNAs that should be tested as candidate biomarkers of response or resistance to chemotherapy; (iii) although losartan therapy alone does not reduce tumor burden, it reduces both the incidence and the amount of ascites formed; and (iv) our retrospective analysis revealed that patients receiving angiotensin system inhibitors concurrently with standard treatment for ovarian cancer exhibited 30 mo longer overall survival compared with patients on other antihypertensives. Our findings provide the rationale and supporting data for a clinical trial on combined losartan and chemotherapy in ovarian cancer patients.


Assuntos
Antineoplásicos/farmacologia , Ascite/patologia , Losartan/farmacologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Células Estromais/patologia , Animais , Ascite/tratamento farmacológico , Colágeno/genética , Colágeno/metabolismo , Modelos Animais de Doenças , Sinergismo Farmacológico , Matriz Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hipóxia/metabolismo , Camundongos , MicroRNAs/genética , Modelos Teóricos , Estadiamento de Neoplasias , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/mortalidade , Prognóstico , Estresse Fisiológico/efeitos dos fármacos , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Nano Lett ; 21(7): 3271-3279, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33755481

RESUMO

This report of the reddest emitting indium phosphide quantum dots (InP QDs) to date demonstrates tunable, near-infrared (NIR) photoluminescence (PL) as well as PL multiplexing in the first optical tissue window while avoiding toxic constituents. This synthesis overcomes the InP "growth bottleneck" and extends the emission peak of InP QDs deeper into the first optical tissue window using an inverted QD heterostructure, specifically ZnSe/InP/ZnS core/shell/shell nanoparticles. The QDs exhibit InP shell thickness-dependent tunable emission with peaks ranging from 515-845 nm. The high absorptivity of InP yields effective photoexcitation of the QDs with UV, visible, and NIR wavelengths. These nanoparticles extend the range of tunable direct-bandgap emission from InP-based nanostructures, effectively overcoming a synthetic barrier that has prevented InP-based QDs from reaching their full potential as NIR imaging agents. Multiplexed lymph node imaging in a mouse model demonstrates the potential of the NIR-emitting InP particles for in vivo imaging.


Assuntos
Fosfinas , Pontos Quânticos , Animais , Índio , Camundongos , Compostos de Zinco
7.
Air Med J ; 40(4): 220-224, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34172228

RESUMO

OBJECTIVE: There are limited data regarding the typical characteristics of coronavirus disease 2019 (COVID-19) patients requiring interfacility transport or the clinical capabilities of the out-of-hospital transport clinicians required to provide safe transport. The objective of this study is to provide epidemiologic data and highlight the clinical skill set and decision making needed to transport critically ill COVID-19 patients. METHODS: A retrospective chart review of persons under investigation for COVID-19 transported during the first 6 months of the pandemic by Johns Hopkins Lifeline was performed. Patients who required interfacility transport and tested positive for severe acute respiratory syndrome coronavirus 2 by polymerase chain reaction assay were included in the analysis. RESULTS: Sixty-eight patients (25.4%) required vasopressor support, 35 patients (13.1%) were pharmacologically paralyzed, 15 (5.60%) were prone, and 1 (0.75%) received an inhaled pulmonary vasodilator. At least 1 ventilator setting change occurred for 59 patients (22.0%), and ventilation mode was changed for 11 patients (4.10%) during transport. CONCLUSION: The safe transport of critically ill patients with COVID-19 requires experience with vasopressors, paralytic medications, inhaled vasodilators, prone positioning, and ventilator management. The frequency of initiated critical interventions and ventilator adjustments underscores the tenuous nature of these patients and highlights the importance of transport clinician reassessment, critical thinking, and decision making.


Assuntos
COVID-19/terapia , Competência Clínica , Tomada de Decisão Clínica/métodos , Cuidados Críticos/métodos , Transporte de Pacientes/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , Terapia Combinada , Cuidados Críticos/normas , Cuidados Críticos/estatística & dados numéricos , Estado Terminal , Feminino , Humanos , Masculino , Maryland , Pessoa de Meia-Idade , Gravidade do Paciente , Transferência de Pacientes/métodos , Transferência de Pacientes/normas , Transferência de Pacientes/estatística & dados numéricos , Estudos Retrospectivos , Transporte de Pacientes/normas , Transporte de Pacientes/estatística & dados numéricos
8.
J Cell Mol Med ; 24(1): 126-138, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31642192

RESUMO

Vascular endothelial growth factor receptors (VEGFRs) are major contributors to angiogenesis and lymphangiogenesis through the binding of VEGF ligands. We have previously shown that the bone marrow tyrosine kinase BMX is critical for inflammatory angiogenesis via its direct transactivation of VEGFR2. In the present study, we show that siRNA-mediated silencing of BMX led to a significant decrease in the total levels of VEGFR2 mRNA and protein, without affecting their stability, in human endothelial cells (ECs). Interestingly, BMX was detected in the nuclei of ECs, and the SH3 domain of BMX was necessary for its nuclear localization. Luciferase assays showed a significant decrease in the Vegfr2 (kdr) gene promoter activity in ECs after BMX silencing, indicating that BMX is necessary for Vegfr2 transcription. In addition, we found that wild-type BMX, but not a catalytic inactive mutant BMX-K445R, promoted Vegfr2 promoter activity and VEGF-induced EC migration and tube sprouting. Mechanistically, we show that the enhancement of Vegfr2 promoter activity by BMX was mediated by Sp1, a transcription factor critical for the Vegfr2 promoter. Loss of BMX significantly reduced Sp1 binding to the Vegfr2 promoter as assayed by chromatin immunoprecipitation assays. Wild-type BMX, but not a kinase-inactive form of BMX, associated with and potentially phosphorylated Sp1. Moreover, a nuclear-targeted BMX (NLS-BMX), but not cytoplasm-localized form (NES-BMX), bound to Sp1 and augmented VEGFR2 expression. In conclusion, we uncovered a novel function of nuclear-localized BMX in regulating VEGFR2 expression and angiogenesis, suggesting that BMX is a therapeutic target for angiogenesis-related diseases.


Assuntos
Núcleo Celular/metabolismo , Regulação da Expressão Gênica , Neovascularização Fisiológica , Regiões Promotoras Genéticas , Proteínas Tirosina Quinases/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Núcleo Celular/genética , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Fosforilação , Transdução de Sinais , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
Semin Cell Dev Biol ; 38: 98-105, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25620792

RESUMO

Lymph nodes are initial sites for cancer metastasis in many solid tumors. However, their role in cancer progression is still not completely understood. Emerging evidence suggests that the lymph node microenvironment provides hospitable soil for the seeding and proliferation of cancer cells. Resident immune and stromal cells in the lymph node express and secrete molecules that may facilitate the survival of cancer cells in this organ. More comprehensive studies are warranted to fully understand the importance of the lymph node in tumor progression. Here, we will review the current knowledge of the role of the lymph node microenvironment in metastatic progression.


Assuntos
Linfonodos/patologia , Metástase Linfática/patologia , Neoplasias/imunologia , Neoplasias/patologia , Animais , Quimiocinas/imunologia , Humanos , Evasão da Resposta Imune , Monitorização Imunológica , Microambiente Tumoral
10.
Microcirculation ; 24(6)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28510992

RESUMO

OBJECTIVE: Lymph node metastases are a poor prognostic factor. Additionally, responses of lymph node metastasis to therapy can be different from the primary tumor. Investigating the physiologic lymph node blood vasculature might give insight into the ability of systemic drugs to penetrate the lymph node, and thus into the differential effect of therapy between lymph node metastasis and primary tumors. Here, we measured effective vascular permeability of lymph node blood vessels and attempted to increase chemotherapy penetration by increasing effective vascular permeability. METHODS: We developed a novel three-dimensional method to measure effective vascular permeability in murine lymph nodes in vivo. VEGF-A was systemically administered to increase effective vascular permeability. Validated high-performance liquid chromatography protocols were used to measure chemotherapeutic drug concentrations in untreated and VEGF-A-treated lymph nodes, liver, spleen, brain, and blood. RESULTS: VEGF-A-treated lymph node blood vessel effective vascular permeability (mean 3.83 × 10-7  cm/s) was significantly higher than untreated lymph nodes (mean 9.87 × 10-8  cm/s). No difference was found in lymph node drug accumulation in untreated versus VEGF-A-treated mice. CONCLUSIONS: Lymph node effective vascular permeability can be increased (~fourfold) by VEGF-A. However, no significant increase in chemotherapy uptake was measured by pretreatment with VEGF-A.


Assuntos
Antineoplásicos/farmacocinética , Permeabilidade Capilar , Linfonodos/irrigação sanguínea , Animais , Transporte Biológico/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Camundongos , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/farmacologia
11.
Trends Cancer ; 10(1): 28-37, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37863720

RESUMO

Early in solid tumor development, antigens are presented in tumor-draining lymph nodes (tdLNs), a process that is necessary to set up immune surveillance. Recent evidence indicates that tdLNs fuel systemic tumor-specific T cell responses which may halt cancer progression and facilitate future responses to immunotherapy. These protective responses, however, are subject to progressive dysfunction exacerbated by lymph node (LN) metastasis. We discuss emerging preclinical and clinical literature indicating that the tdLN is a crucial reservoir for systemic immunity that can potentiate immune surveillance. We also discuss the impact of LN metastasis and argue that a better understanding of the relationship between LN metastasis and systemic immunity will be necessary to direct regional disease management in the era of immunotherapy.


Assuntos
Linfonodos , Linfócitos T , Humanos , Metástase Linfática/patologia , Imunoterapia
12.
Int J Biol Macromol ; 276(Pt 1): 133734, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002903

RESUMO

In this study, Kraft lignin was modified by ammonium dihydrogen phosphate (ADP) and urea for achieving phosphorylation and carbamylation, aiming to protect wood against biological and fire attack. Scots pine (Pinus sylvestris L.) sapwood was impregnated with a water solution containing Kraft lignin, ADP, and urea, followed by heat treatment at 150 °C, resulting in changes in the properties of the Kraft lignin as well as the wood matrix. Infrared spectroscopy, 13C cross-polarisation magic-angle-spinning (MAS) nuclear magnetic resonance (NMR), and direct excitation single-pulse 31P MAS NMR analyses suggested the grafting reaction of phosphate and carbamylate groups onto the hydroxyl groups of Kraft lignin. Scanning electron microscopy with energy dispersive X-ray spectroscopy indicated that the condensed Kraft lignin filled the lumen as well as partially penetrating the wood cell wall. The modified Kraft lignin imparted fire-retardancy and increased char residue to the wood at elevated temperature, as confirmed by limiting oxygen index, microscale combustion calorimetry, and thermogravimetric analysis. The modified wood exhibited superior resistance against mold and decay fungi attack under laboratory conditions. The modified wood had a similar modulus of elasticity to the unmodified wood, while experiencing a reduction in the modulus of rupture.

13.
Am J Pathol ; 180(4): 1715-25, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22310467

RESUMO

Lymphatic vessels (LVs) are important structures for antigen presentation, for lipid metabolism, and as conduits for tumor metastases, but they have been difficult to visualize in vivo. Prox1 is a transcription factor that is necessary for lymphangiogenesis in ontogeny and the maintenance of LVs. To visualize LVs in the lymph node of a living mouse in real time, we made the ProxTom transgenic mouse in a C57BL/6 background using red fluorescent LVs that are suitable for in vivo imaging. The ProxTom transgene contained all Prox1 regulatory sequences and was faithfully expressed in LVs coincident with endogenous Prox1 expression. The progenies of a ProxTom × Hec6stGFP cross were imaged using two-photon laser scanning microscopy, allowing the simultaneous visualization of LVs and high endothelial venules in a lymph node of a living mouse for the first time. We confirmed the expression of Prox1 in the adult liver, lens, and dentate gyrus. These intensely fluorescent mice revealed the expression of Prox1 in three novel sites: the neuroendocrine cells of the adrenal medulla, megakaryocytes, and platelets. The novel sites identified herein suggest previously unknown roles for Prox1. The faithful expression of the fluorescent reporter in ProxTom LVs indicates that these mice have potential utility in the study of diseases as diverse as lymphedema, filariasis, transplant rejection, obesity, and tumor metastasis.


Assuntos
Medula Suprarrenal/metabolismo , Plaquetas/metabolismo , Proteínas de Homeodomínio/metabolismo , Vasos Linfáticos/metabolismo , Megacariócitos/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Células Cultivadas , Citoplasma/metabolismo , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/fisiologia , Genótipo , Glicoproteínas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas Luminescentes/metabolismo , Linfonodos/metabolismo , Proteínas de Membrana Transportadoras , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia de Fluorescência , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/genética , Proteína Vermelha Fluorescente
14.
Arterioscler Thromb Vasc Biol ; 32(3): 633-42, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22223733

RESUMO

OBJECTIVE: Vascular endothelial growth factor receptor(VEGFR)-3 is a critical regulator of developmental and adult vasculogenesis and lymphangiogenesis through its interactions with select members of the VEGF family. The goal of this study was to investigate how VEGFR-3 expression is regulated during inflammatory lymphangiogenesis. METHODS AND RESULTS: In this study, we present for the first time evidence that VEGFR-3 can be negatively regulated by a mirtron, hsa-miR-1236 (miR-1236), which is expressed in primary human lymphatic endothelial cells. In human lymphatic endothelial cells, miR-1236 is upregulated in response to IL-1ß, a negative regulator of VEGFR-3. miR-1236 binds the 3' untranslated region of Vegfr3, resulting in translational inhibition. Overexpression of miR-1236 significantly decreased expression of VEGFR-3, but not VEGFR-2, in human lymphatic endothelial cells. Compared to a control miR, overexpression of miR-1236 also led to decreased VEGFR-3 signaling. However, VEGFR-2-specific signaling was not affected. miR-1236 can attenuate human lymphatic endothelial cell migration and tube formation, as well as in vivo lymphangiogenesis. CONCLUSION: Our data suggest that miR-1236 may function as a negative regulator of VEGFR-3 signaling during inflammatory lymphangiogenesis.


Assuntos
Células Endoteliais/metabolismo , Inflamação/genética , Linfangiogênese/genética , Vasos Linfáticos/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Regiões 3' não Traduzidas , Animais , Sítios de Ligação , Células COS , Movimento Celular , Chlorocebus aethiops , Regulação para Baixo , Células Endoteliais/imunologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/fisiopatologia , Interleucina-1beta/metabolismo , Vasos Linfáticos/imunologia , Vasos Linfáticos/fisiopatologia , Masculino , Camundongos , Interferência de RNA , Transfecção , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
15.
bioRxiv ; 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37333242

RESUMO

Preclinical models that display spontaneous metastasis are necessary to improve therapeutic options for hormone receptor positive breast cancers. In this study, we conducted a detailed cellular and molecular characterization of MCa-P1362, a novel syngeneic Balb/c mouse model of metastatic breast cancer. MCa-P1362 cancer cells expressed estrogen receptors (ER), progesterone receptors (PR), and HER-2 receptors. MCa-P1362 cells proliferate in vitro and in vivo in response to estrogen, yet do not depend on steroid hormones for tumor progression. Further characterization of MCa-P1362 tumor explants shows that they contain a mixture of epithelial cancer cells and stromal cells. Based on transcriptomic and functional analyses of cancer and stromal cells, stem cells are present in both populations. Functional studies demonstrate that crosstalk between cancer and stromal cells promotes tumor growth, metastasis, and drug resistance. MCa-P1362 may serve as a useful preclinical model to investigate the cellular and molecular basis of hormone receptor positive tumor progression and therapeutic resistance.

16.
Polymers (Basel) ; 15(15)2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37571145

RESUMO

This study determined the impact of undertaking an initial treatment of oak wood by sealing its surface pores with epoxy resin, focusing on the durability of transparent coating systems when exposed outdoors. Throughout the exposure period, various parameters including color, gloss, surface wettability, and both macroscopic and microscopic surface evaluation were continuously monitored. The study involved two sets of samples: one set underwent the pretreatment, while the other did not. Subsequently, four coating systems were applied to the samples, comprising two solvent-based and two water-based coatings. The experiment was conducted over a period of two years, utilizing natural weathering methods within the premises of the Czech University of Life Sciences in Prague. The pretreatment with epoxy resin exhibited enhanced durability for all paint systems. The analysis showed a significant difference in gloss and color after 12 months of weathering exposure without any significant effect on surface wettability and sealing. However, after 24 months of the weathering exposure, no significant differences between the sealed and unsealed surface were observed. The most significant change in properties was noted for the water-based coatings used in coating systems number 3 and 4, and these coatings were rated as the best.

17.
Materials (Basel) ; 16(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38005130

RESUMO

Particleboards with different combinations of the adhesive material imidazole, citric acid, and sorbitol were produced. Softwood sawdust from a Swedish sawmill was mixed with an aqueous solution of the chemicals and then dried to 0% moisture content prior to pressing. The boards were pressed to a target density of 700 kg m-3 at either 200 °C or 220 °C for 10 min. The hygroscopic and mechanical properties of the boards were clearly better at 220 °C than 200 °C for all used chemical combinations. A combination of imidazole (14.4 wt%) and citric acid (11.3 wt%) led to the best results, where the thickness swelling after 24 h of water immersion was 6.3% and the internal bonding strength was 0.57 MPa. The modulus of rupture and modulus of elasticity were 3.3 MPa and 1.1 GPa, respectively. Cyclic accelerated weathering showed exceptional stability with a thickness change after boiling and drying of only 2.1% compared to the initial dry thickness. This study indicates that the presence of imidazole leads to greatly improved hygroscopic properties and good internal bonding strength when used in particleboards.

18.
ACS Omega ; 8(12): 11381-11396, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37008136

RESUMO

The exterior application of fire-retardant (FR) timber necessitates it to have high durability because of the possibility to be exposed to rainfall. In this study, water-leaching resistance of FR wood has been imparted by grafting phosphate and carbamate groups of the water-soluble FR additives ammonium dihydrogen phosphate (ADP)/urea onto the hydroxyl groups of wood polymers via vacuum-pressure impregnation, followed by drying/heating in hot air. A darker and more reddish wood surface was observed after the modification. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, solid-state 13C cross-polarization magic-angle-spinning nuclear magnetic resonance (13C CP-MAS NMR), and direct-excitation 31P MAS NMR suggested the formation of C-O-P covalent bonds and urethane chemical bridges. Scanning electron microscopy/energy-dispersive X-ray spectrometry suggested the diffusion of ADP/urea into the cell wall. The gas evolution analyzed by thermogravimetric analysis coupled with quadrupole mass spectrometry revealed a potential grafting reaction mechanism starting with the thermal decomposition of urea. Thermal behavior showed that the FR-modified wood lowered the main decomposition temperature and promoted the formation of char residues at elevated temperatures. The FR activity was preserved even after an extensive water-leaching test, confirmed by the limiting oxygen index (LOI) and cone calorimetry. The reduction of fire hazards was achieved through the increase of the LOI to above 80%, reduction of 30% of the peak heat release rate (pHRR2), reduction of smoke production, and a longer ignition time. The modulus of elasticity of FR-modified wood increased by 40% without significantly decreasing the modulus of rupture.

19.
J Exp Med ; 220(9)2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37341991

RESUMO

Tumor-draining lymph nodes (TDLNs) are important for tumor antigen-specific T cell generation and effective anticancer immune responses. However, TDLNs are often the primary site of metastasis, causing immune suppression and worse outcomes. Through cross-species single-cell RNA-Seq analysis, we identified features defining cancer cell heterogeneity, plasticity, and immune evasion during breast cancer progression and lymph node metastasis (LNM). A subset of cancer cells in the lymph nodes exhibited elevated MHC class II (MHC-II) gene expression in both mice and humans. MHC-II+ cancer cells lacked costimulatory molecule expression, leading to regulatory T cell (Treg) expansion and fewer CD4+ effector T cells in TDLNs. Genetic knockout of MHC-II reduced LNM and Treg expansion, while overexpression of the MHC-II transactivator, Ciita, worsened LNM and caused excessive Treg expansion. These findings demonstrate that cancer cell MHC-II expression promotes metastasis and immune evasion in TDLNs.


Assuntos
Neoplasias da Mama , Humanos , Animais , Camundongos , Feminino , Neoplasias da Mama/patologia , Plasticidade Celular , Linfonodos , Linfócitos T Reguladores , Metástase Linfática/patologia , Tolerância Imunológica , Melanoma Maligno Cutâneo
20.
bioRxiv ; 2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38014141

RESUMO

Lymphatic muscle cells (LMCs) within the wall of collecting lymphatic vessels exhibit tonic and autonomous phasic contractions, which drive active lymph transport to maintain tissue-fluid homeostasis and support immune surveillance. Damage to LMCs disrupts lymphatic function and is related to various diseases. Despite their importance, knowledge of the transcriptional signatures in LMCs and how they relate to lymphatic function in normal and disease contexts is largely missing. We have generated a comprehensive transcriptional single-cell atlas-including LMCs-of collecting lymphatic vessels in mouse dermis at various ages. We identified genes that distinguish LMCs from other types of muscle cells, characterized the phenotypical and transcriptomic changes in LMCs in aged vessels, and uncovered a pro-inflammatory microenvironment that suppresses the contractile apparatus in advanced-aged LMCs. Our findings provide a valuable resource to accelerate future research for the identification of potential drug targets on LMCs to preserve lymphatic vessel function as well as supporting studies to identify genetic causes of primary lymphedema currently with unknown molecular explanation.

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