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1.
Proc Natl Acad Sci U S A ; 121(14): e2321336121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38530888

RESUMO

Host-directed therapies (HDTs) represent an emerging approach for bacterial clearance during tuberculosis (TB) infection. While most HDTs are designed and implemented for immuno-modulation, other host targets-such as nonimmune stromal components found in pulmonary granulomas-may prove equally viable. Building on our previous work characterizing and normalizing the aberrant granuloma-associated vasculature, here we demonstrate that FDA-approved therapies (bevacizumab and losartan, respectively) can be repurposed as HDTs to normalize blood vessels and extracellular matrix (ECM), improve drug delivery, and reduce bacterial loads in TB granulomas. Granulomas feature an overabundance of ECM and compressed blood vessels, both of which are effectively reduced by losartan treatment in the rabbit model of TB. Combining both HDTs promotes secretion of proinflammatory cytokines and improves anti-TB drug delivery. Finally, alone and in combination with second-line antitubercular agents (moxifloxacin or bedaquiline), these HDTs significantly reduce bacterial burden. RNA sequencing analysis of HDT-treated lung and granuloma tissues implicates up-regulated antimicrobial peptide and proinflammatory gene expression by ciliated epithelial airway cells as a putative mechanism of the observed antitubercular benefits in the absence of chemotherapy. These findings demonstrate that bevacizumab and losartan are well-tolerated stroma-targeting HDTs, normalize the granuloma microenvironment, and improve TB outcomes, providing the rationale to clinically test this combination in TB patients.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Humanos , Animais , Coelhos , Bevacizumab/farmacologia , Losartan/farmacologia , Tuberculose/microbiologia , Antituberculosos/farmacologia , Granuloma , Tuberculose Latente/microbiologia
2.
Proc Natl Acad Sci U S A ; 120(6): e2219199120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36724255

RESUMO

Immune checkpoint blockers (ICBs) have failed in all phase III glioblastoma trials. Here, we found that ICBs induce cerebral edema in some patients and mice with glioblastoma. Through single-cell RNA sequencing, intravital imaging, and CD8+ T cell blocking studies in mice, we demonstrated that this edema results from an inflammatory response following antiprogrammed death 1 (PD1) antibody treatment that disrupts the blood-tumor barrier. Used in lieu of immunosuppressive corticosteroids, the angiotensin receptor blocker losartan prevented this ICB-induced edema and reprogrammed the tumor microenvironment, curing 20% of mice which increased to 40% in combination with standard of care treatment. Using a bihemispheric tumor model, we identified a "hot" tumor immune signature prior to losartan+anti-PD1 therapy that predicted long-term survival. Our findings provide the rationale and associated biomarkers to test losartan with ICBs in glioblastoma patients.


Assuntos
Glioblastoma , Animais , Camundongos , Glioblastoma/patologia , Losartan/farmacologia , Losartan/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Linfócitos T CD8-Positivos , Edema , Microambiente Tumoral
3.
PLoS Comput Biol ; 20(2): e1011847, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38335224

RESUMO

Physiological abnormalities in pulmonary granulomas-pathological hallmarks of tuberculosis (TB)-compromise the transport of oxygen, nutrients, and drugs. In prior studies, we demonstrated mathematically and experimentally that hypoxia and necrosis emerge in the granuloma microenvironment (GME) as a direct result of limited oxygen availability. Building on our initial model of avascular oxygen diffusion, here we explore additional aspects of oxygen transport, including the roles of granuloma vasculature, transcapillary transport, plasma dilution, and interstitial convection, followed by cellular metabolism. Approximate analytical solutions are provided for oxygen and glucose concentration, interstitial fluid velocity, interstitial fluid pressure, and the thickness of the convective zone. These predictions are in agreement with prior experimental results from rabbit TB granulomas and from rat carcinoma models, which share similar transport limitations. Additional drug delivery predictions for anti-TB-agents (rifampicin and clofazimine) strikingly match recent spatially-resolved experimental results from a mouse model of TB. Finally, an approach to improve molecular transport in granulomas by modulating interstitial hydraulic conductivity is tested in silico.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Coelhos , Oxigênio/metabolismo , Tuberculose/tratamento farmacológico , Tuberculose/patologia , Granuloma/patologia , Modelos Animais de Doenças , Nutrientes , Mycobacterium tuberculosis/metabolismo
4.
Biophys J ; 123(9): 1098-1105, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38544410

RESUMO

Understanding cancer cell mechanics allows for the identification of novel disease mechanisms, diagnostic biomarkers, and targeted therapies. In this study, we utilized our previously established fluid shear stress assay to investigate and compare the viscoelastic properties of normal immortalized human astrocytes and invasive human glioblastoma (GBM) cells when subjected to physiological levels of shear stress that are present in the brain microenvironment. We used a parallel-flow microfluidic shear system and a camera-coupled optical microscope to expose single cells to fluid shear stress and monitor the resulting deformation in real time, respectively. From the video-rate imaging, we fed cell deformation information from digital image correlation into a three-parameter generalized Maxwell model to quantify the nuclear and cytoplasmic viscoelastic properties of single cells. We further quantified actin cytoskeleton density and alignment in immortalized human astrocytes and GBM cells via fluorescence microscopy and image analysis techniques. Results from our study show that contrary to the behavior of many extracranial cells, normal and cancerous brain cells do not exhibit significant differences in their viscoelastic properties. Moreover, we also found that the viscoelastic properties of the nucleus and cytoplasm as well as the actin cytoskeletal densities of both brain cell types are similar. Our work suggests that malignant GBM cells exhibit unique mechanical behaviors not seen in other cancer cell types. These results warrant future studies to elucidate the distinct biophysical characteristics of the brain and reveal novel mechanical attributes of GBM and other primary brain tumors.


Assuntos
Astrócitos , Neoplasias Encefálicas , Elasticidade , Glioblastoma , Análise de Célula Única , Humanos , Viscosidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Astrócitos/metabolismo , Astrócitos/citologia , Glioblastoma/patologia , Glioblastoma/metabolismo , Fenômenos Biomecânicos , Encéfalo/metabolismo , Encéfalo/patologia , Núcleo Celular/metabolismo , Estresse Mecânico , Citoesqueleto de Actina/metabolismo
5.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34725151

RESUMO

Liver metastasis is a major cause of mortality for patients with colorectal cancer (CRC). Mismatch repair-proficient (pMMR) CRCs make up about 95% of metastatic CRCs, and are unresponsive to immune checkpoint blockade (ICB) therapy. Here we show that mouse models of orthotopic pMMR CRC liver metastasis accurately recapitulate the inefficacy of ICB therapy in patients, whereas the same pMMR CRC tumors are sensitive to ICB therapy when grown subcutaneously. To reveal local, nonmalignant components that determine CRC sensitivity to treatment, we compared the microenvironments of pMMR CRC cells grown as liver metastases and subcutaneous tumors. We found a paucity of both activated T cells and dendritic cells in ICB-treated orthotopic liver metastases, when compared with their subcutaneous tumor counterparts. Furthermore, treatment with Feline McDonough sarcoma (FMS)-like tyrosine kinase 3 ligand (Flt3L) plus ICB therapy increased dendritic cell infiltration into pMMR CRC liver metastases and improved mouse survival. Lastly, we show that human CRC liver metastases and microsatellite stable (MSS) primary CRC have a similar paucity of T cells and dendritic cells. These studies indicate that orthotopic tumor models, but not subcutaneous models, should be used to guide human clinical trials. Our findings also posit dendritic cells as antitumor components that can increase the efficacy of immunotherapies against pMMR CRC.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA , Células Dendríticas , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Interferon gama/uso terapêutico , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/secundário , Masculino , Camundongos Endogâmicos C57BL
6.
Proc Natl Acad Sci U S A ; 117(2): 1129-1138, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31879345

RESUMO

Immunotherapy directed at the PD-L1/PD-1 axis has produced treatment advances in various human cancers. Unfortunately, progress has not extended to glioblastoma (GBM), with phase III clinical trials assessing anti-PD-1 monotherapy failing to show efficacy in newly diagnosed and recurrent tumors. Myeloid-derived suppressor cells (MDSCs), a subset of immunosuppressive myeloid derived cells, are known to infiltrate the tumor microenvironment of GBM. Growing evidence suggests the CCL2-CCR2 axis is important for this process. This study evaluated the combination of PD-1 blockade and CCR2 inhibition in anti-PD-1-resistant gliomas. CCR2 deficiency unmasked an anti-PD-1 survival benefit in KR158 glioma-bearing mice. CD11b+/Ly6Chi/PD-L1+ MDSCs within established gliomas decreased with a concomitant increase in overall CCR2+ cells and MDSCs within bone marrow of CCR2-deficient mice. The CCR2 antagonist CCX872 increased median survival as a monotherapy in KR158 glioma-bearing animals and further increased median and overall survival when combined with anti-PD-1. Additionally, combination of CCX872 and anti-PD-1 prolonged median survival time in 005 GSC GBM-bearing mice. In both models, CCX872 decreased tumor associated MDSCs and increased these cells within the bone marrow. Examination of tumor-infiltrating lymphocytes revealed an elevated population, increased IFNγ expression, indicating enhanced cytolytic activity, as well as decreased expression of exhaustion markers in CD4+ and CD8+ T cells following combination treatment. These data establish that combining CCR2 and PD-1 blockade extends survival in clinically relevant murine glioma models and provides the basis on which to advance this combinatorial treatment toward early-phase human trials.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Glioma/tratamento farmacológico , Células Mieloides/metabolismo , Receptores CCR2/efeitos dos fármacos , Receptores CCR2/metabolismo , Animais , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Receptor 1 de Quimiocina CX3C/genética , Receptor 1 de Quimiocina CX3C/metabolismo , Quimiocina CCL2 , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioma/patologia , Humanos , Imunoterapia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/efeitos dos fármacos , Células Supressoras Mieloides/metabolismo , Receptor de Morte Celular Programada 1 , Receptores CCR2/genética , Análise de Sobrevida , Microambiente Tumoral/efeitos dos fármacos
7.
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
8.
Hepatology ; 71(4): 1247-1261, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31378984

RESUMO

BACKGROUND AND AIMS: Activation of the antitumor immune response using programmed death receptor-1 (PD-1) blockade showed benefit only in a fraction of patients with hepatocellular carcinoma (HCC). Combining PD-1 blockade with antiangiogenesis has shown promise in substantially increasing the fraction of patients with HCC who respond to treatment, but the mechanism of this interaction is unknown. APPROACH AND RESULTS: We recapitulated these clinical outcomes using orthotopic-grafted or induced-murine models of HCC. Specific blockade of vascular endothelial receptor 2 (VEGFR-2) using a murine antibody significantly delayed primary tumor growth but failed to prolong survival, while anti-PD-1 antibody treatment alone conferred a minor survival advantage in one model. However, dual anti-PD-1/VEGFR-2 therapy significantly inhibited primary tumor growth and doubled survival in both models. Combination therapy reprogrammed the immune microenvironment by increasing cluster of differentiation 8-positive (CD8+ ) cytotoxic T cell infiltration and activation, shifting the M1/M2 ratio of tumor-associated macrophages and reducing T regulatory cell (Treg) and chemokine (C-C motif) receptor 2-positive monocyte infiltration in HCC tissue. In these models, VEGFR-2 was selectively expressed in tumor endothelial cells. Using spheroid cultures of HCC tissue, we found that PD-ligand 1 expression in HCC cells was induced in a paracrine manner upon anti-VEGFR-2 blockade in endothelial cells in part through interferon-gamma expression. Moreover, we found that VEGFR-2 blockade increased PD-1 expression in tumor-infiltrating CD4+ cells. We also found that under anti-PD-1 therapy, CD4+ cells promote normalized vessel formation in the face of antiangiogenic therapy with anti-VEGFR-2 antibody. CONCLUSIONS: We show that dual anti-PD-1/VEGFR-2 therapy has a durable vessel fortification effect in HCC and can overcome treatment resistance to either treatment alone and increase overall survival in both anti-PD-1 therapy-resistant and anti-PD-1 therapy-responsive HCC models.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Anticorpos/uso terapêutico , Carcinoma Hepatocelular/irrigação sanguínea , Linhagem Celular Tumoral , Neoplasias Hepáticas/irrigação sanguínea , Linfócitos do Interstício Tumoral , Camundongos , Neoplasias Experimentais , Receptor de Morte Celular Programada 1/imunologia , Esferoides Celulares , Linfócitos T Citotóxicos , Macrófagos Associados a Tumor , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologia
9.
Proc Natl Acad Sci U S A ; 115(37): E8717-E8726, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30150398

RESUMO

Blood-brain/blood-tumor barriers (BBB and BTB) and interstitial transport may constitute major obstacles to the transport of therapeutics in brain tumors. In this study, we examined the impact of focused ultrasound (FUS) in combination with microbubbles on the transport of two relevant chemotherapy-based anticancer agents in breast cancer brain metastases at cellular resolution: doxorubicin, a nontargeted chemotherapeutic, and ado-trastuzumab emtansine (T-DM1), an antibody-drug conjugate. Using an orthotopic xenograft model of HER2-positive breast cancer brain metastasis and quantitative microscopy, we demonstrate significant increases in the extravasation of both agents (sevenfold and twofold for doxorubicin and T-DM1, respectively), and we provide evidence of increased drug penetration (>100 vs. <20 µm and 42 ± 7 vs. 12 ± 4 µm for doxorubicin and T-DM1, respectively) after the application of FUS compared with control (non-FUS). Integration of experimental data with physiologically based pharmacokinetic (PBPK) modeling of drug transport reveals that FUS in combination with microbubbles alleviates vascular barriers and enhances interstitial convective transport via an increase in hydraulic conductivity. Experimental data demonstrate that FUS in combination with microbubbles enhances significantly the endothelial cell uptake of the small chemotherapeutic agent. Quantification with PBPK modeling reveals an increase in transmembrane transport by more than two orders of magnitude. PBPK modeling indicates a selective increase in transvascular transport of doxorubicin through small vessel wall pores with a narrow range of sizes (diameter, 10-50 nm). Our work provides a quantitative framework for the optimization of FUS-drug combinations to maximize intratumoral drug delivery and facilitate the development of strategies to treat brain metastases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Ado-Trastuzumab Emtansina , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Barreira Hematoencefálica/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundário , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Humanos , Maitansina/administração & dosagem , Maitansina/análogos & derivados , Maitansina/farmacocinética , Camundongos , Microbolhas , Trastuzumab/administração & dosagem , Trastuzumab/farmacocinética , Ultrassonografia/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Proc Natl Acad Sci U S A ; 115(17): 4465-4470, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29626132

RESUMO

Fluorescence imaging is a method of real-time molecular tracking in vivo that has enabled many clinical technologies. Imaging in the shortwave IR (SWIR; 1,000-2,000 nm) promises higher contrast, sensitivity, and penetration depths compared with conventional visible and near-IR (NIR) fluorescence imaging. However, adoption of SWIR imaging in clinical settings has been limited, partially due to the absence of US Food and Drug Administration (FDA)-approved fluorophores with peak emission in the SWIR. Here, we show that commercially available NIR dyes, including the FDA-approved contrast agent indocyanine green (ICG), exhibit optical properties suitable for in vivo SWIR fluorescence imaging. Even though their emission spectra peak in the NIR, these dyes outperform commercial SWIR fluorophores and can be imaged in the SWIR, even beyond 1,500 nm. We show real-time fluorescence imaging using ICG at clinically relevant doses, including intravital microscopy, noninvasive imaging in blood and lymph vessels, and imaging of hepatobiliary clearance, and show increased contrast compared with NIR fluorescence imaging. Furthermore, we show tumor-targeted SWIR imaging with IRDye 800CW-labeled trastuzumab, an NIR dye being tested in multiple clinical trials. Our findings suggest that high-contrast SWIR fluorescence imaging can be implemented alongside existing imaging modalities by switching the detection of conventional NIR fluorescence systems from silicon-based NIR cameras to emerging indium gallium arsenide-based SWIR cameras. Using ICG in particular opens the possibility of translating SWIR fluorescence imaging to human clinical applications. Indeed, our findings suggest that emerging SWIR-fluorescent in vivo contrast agents should be benchmarked against the SWIR emission of ICG in blood.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Meios de Contraste , Corantes Fluorescentes , Raios Infravermelhos , Microscopia Intravital/métodos , Vasos Linfáticos/diagnóstico por imagem , Animais , Bovinos , Meios de Contraste/farmacocinética , Meios de Contraste/farmacologia , Corantes Fluorescentes/farmacocinética , Corantes Fluorescentes/farmacologia , Verde de Indocianina , Camundongos , Microscopia de Fluorescência/métodos , Trastuzumab/farmacocinética , Trastuzumab/farmacologia
11.
Proc Natl Acad Sci U S A ; 113(16): 4470-5, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27044097

RESUMO

Glioblastomas (GBMs) rapidly become refractory to anti-VEGF therapies. We previously demonstrated that ectopic overexpression of angiopoietin-2 (Ang-2) compromises the benefits of anti-VEGF receptor (VEGFR) treatment in murine GBM models and that circulating Ang-2 levels in GBM patients rebound after an initial decrease following cediranib (a pan-VEGFR tyrosine kinase inhibitor) administration. Here we tested whether dual inhibition of VEGFR/Ang-2 could improve survival in two orthotopic models of GBM, Gl261 and U87. Dual therapy using cediranib and MEDI3617 (an anti-Ang-2-neutralizing antibody) improved survival over each therapy alone by delaying Gl261 growth and increasing U87 necrosis, effectively reducing viable tumor burden. Consistent with their vascular-modulating function, the dual therapies enhanced morphological normalization of vessels. Dual therapy also led to changes in tumor-associated macrophages (TAMs). Inhibition of TAM recruitment using an anti-colony-stimulating factor-1 antibody compromised the survival benefit of dual therapy. Thus, dual inhibition of VEGFR/Ang-2 prolongs survival in preclinical GBM models by reducing tumor burden, improving normalization, and altering TAMs. This approach may represent a potential therapeutic strategy to overcome the limitations of anti-VEGFR monotherapy in GBM patients by integrating the complementary effects of anti-Ang2 treatment on vessels and immune cells.


Assuntos
Anticorpos Antineoplásicos/farmacologia , Glioblastoma , Macrófagos , Proteínas de Neoplasias , Neoplasias Experimentais , Neovascularização Patológica , Quinazolinas/farmacologia , Receptores de Fatores de Crescimento do Endotélio Vascular , Ribonuclease Pancreático , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ribonuclease Pancreático/antagonistas & inibidores , Ribonuclease Pancreático/metabolismo
12.
Proc Natl Acad Sci U S A ; 113(16): 4476-81, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27044098

RESUMO

Inhibition of the vascular endothelial growth factor (VEGF) pathway has failed to improve overall survival of patients with glioblastoma (GBM). We previously showed that angiopoietin-2 (Ang-2) overexpression compromised the benefit from anti-VEGF therapy in a preclinical GBM model. Here we investigated whether dual Ang-2/VEGF inhibition could overcome resistance to anti-VEGF treatment. We treated mice bearing orthotopic syngeneic (Gl261) GBMs or human (MGG8) GBM xenografts with antibodies inhibiting VEGF (B20), or Ang-2/VEGF (CrossMab, A2V). We examined the effects of treatment on the tumor vasculature, immune cell populations, tumor growth, and survival in both the Gl261 and MGG8 tumor models. We found that in the Gl261 model, which displays a highly abnormal tumor vasculature, A2V decreased vessel density, delayed tumor growth, and prolonged survival compared with B20. In the MGG8 model, which displays a low degree of vessel abnormality, A2V induced no significant changes in the tumor vasculature but still prolonged survival. In both the Gl261 and MGG8 models A2V reprogrammed protumor M2 macrophages toward the antitumor M1 phenotype. Our findings indicate that A2V may prolong survival in mice with GBM by reprogramming the tumor immune microenvironment and delaying tumor growth.


Assuntos
Anticorpos Biespecíficos/farmacologia , Anticorpos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Glioblastoma/tratamento farmacológico , Macrófagos/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias Experimentais/tratamento farmacológico , Ribonuclease Pancreático/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Proteínas de Transporte Vesicular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Macrófagos/patologia , Camundongos , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Ribonuclease Pancreático/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Proc Natl Acad Sci U S A ; 112(6): 1827-32, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25624495

RESUMO

Tuberculosis (TB) causes almost 2 million deaths annually, and an increasing number of patients are resistant to existing therapies. Patients who have TB require lengthy chemotherapy, possibly because of poor penetration of antibiotics into granulomas where the bacilli reside. Granulomas are morphologically similar to solid cancerous tumors in that they contain hypoxic microenvironments and can be highly fibrotic. Here, we show that TB-infected rabbits have impaired small molecule distribution into these disease sites due to a functionally abnormal vasculature, with a low-molecular-weight tracer accumulating only in peripheral regions of granulomatous lesions. Granuloma-associated vessels are morphologically and spatially heterogeneous, with poor vessel pericyte coverage in both human and experimental rabbit TB granulomas. Moreover, we found enhanced VEGF expression in both species. In tumors, antiangiogenic, specifically anti-VEGF, treatments can "normalize" their vasculature, reducing hypoxia and creating a window of opportunity for concurrent chemotherapy; thus, we investigated vessel normalization in rabbit TB granulomas. Treatment of TB-infected rabbits with the anti-VEGF antibody bevacizumab significantly decreased the total number of vessels while normalizing those vessels that remained. As a result, hypoxic fractions of these granulomas were reduced and small molecule tracer delivery was increased. These findings demonstrate that bevacizumab treatment promotes vascular normalization, improves small molecule delivery, and decreases hypoxia in TB granulomas, thereby providing a potential avenue to improve delivery and efficacy of current treatment regimens.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Vasos Sanguíneos/efeitos dos fármacos , Granuloma do Sistema Respiratório/tratamento farmacológico , Granuloma do Sistema Respiratório/metabolismo , Tuberculose/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Bevacizumab , Vasos Sanguíneos/patologia , Corantes/farmacocinética , Granuloma do Sistema Respiratório/etiologia , Humanos , Pericitos/patologia , Tomografia por Emissão de Pósitrons , Coelhos , Tomografia Computadorizada por Raios X , Tuberculose/complicações
14.
J Neurooncol ; 134(2): 325-330, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28631191

RESUMO

Given prior studies that suggest the use of angiotensin system inhibitors (ASIs) is associated with prolonged overall survival (OS) in glioblastoma (GBM) patients, we evaluated the effect of ASIs in glioma patients receiving chemotherapy and/or bevacizumab (BEV). Using retrospective IRB-approved electronic chart review of newly diagnosed WHO grade 2-4 glioma patients from the Kaiser Permanente Tumor Registry of Northern California, we evaluated the impact of ASIs on OS by Cox proportional hazard model analysis for subgroups who received cytotoxic therapy, cytotoxic therapy with BEV, or BEV alone, as well as those with recurrent GBM (rGBM). Of the 1186 glioma patients who received chemotherapy ASI exposure improved OS (HR 0.82; 95% CI 0.71, 0.93; p = 0.003). When stratified by BEV exposure, a sub-analysis revealed further OS advantage for the BEV group (HR 0.75, 95% CI 0.62, 0.90; p = 0.002). In a second cohort of 181 rGBM patients who received BEV in varying dosages, ASI exposure conferred an OS advantage (HR 0.649; 95% CI 0.46, 0.92; p = 0.016). Moreover, patients with ASI exposure who received low-dose BEV treatment (AUCBEV < 3.6 mg wk/kg) had a significantly longer OS (median = 99 weeks; 95% CI 44.3, 205) than those without ASI (median OS = 55.6 weeks; 95% CI 37.7-73.7; p = 0.032). ASI use is associated with longer OS in glioma patients. Further survival advantage with ASI use was observed in rGBM patients receiving low-dose bevacizumab. These data warrant prospective evaluation of adding ASI to low-dose BEV treatment in GBM patients to improve the outcome of standard therapies.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Quimioterapia Combinada , Feminino , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Gradação de Tumores , Recidiva Local de Neoplasia/tratamento farmacológico , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos
15.
bioRxiv ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38826201

RESUMO

Background: The brain glymphatic system is currently being explored in the context of many neurological disorders and diseases, including traumatic brain injury, Alzheimer's disease, and ischemic stroke. However, little is known about the impact of brain tumors on glymphatic function. Mechanical forces generated during tumor development and growth may be responsible for compromised glymphatic transport pathways, reducing waste clearance and cerebrospinal fluid (CSF) transport in the brain parenchyma. One such force is solid stress, i.e., growth-induced forces from cell hyperproliferation and excess matrix deposition. Because there are no prior studies assessing the impact of tumor-derived solid stress on glymphatic system structure and performance in the brain parenchyma, this study serves to fill an important gap in the field. Methods: We adapted a previously developed Electrical Analog Model using MATLAB Simulink for glymphatic transport coupled with Finite Element Analysis for tumor mechanical stresses and strains in COMSOL. This allowed simulation of the impact of tumor mechanical force generation on fluid transport within brain parenchymal glymphatic units - which include paravascular spaces, astrocytic networks, interstitial spaces, and capillary basement membranes. We conducted a parametric analysis to compare the contributions of tumor size, tumor proximity, and ratio of glymphatic subunits to the stress and strain experienced by the glymphatic unit and corresponding reduction in flow rate of CSF. Results: Mechanical stresses intensify with proximity to the tumor and increasing tumor size, highlighting the vulnerability of nearby glymphatic units to tumor-derived forces. Our stress and strain profiles reveal compressive deformation of these surrounding glymphatics and demonstrate that varying the relative contributions of astrocytes vs. interstitial spaces impact the resulting glymphatic structure significantly under tumor mechanical forces. Increased tumor size and proximity caused increased stress and strain across all glymphatic subunits, as does decreased astrocyte composition. Indeed, our model reveals an inverse correlation between extent of astrocyte contribution to the composition of the glymphatic unit and the resulting mechanical stress. This increased mechanical strain across the glymphatic unit decreases the venous efflux rate of CSF, dependent on the degree of strain and the specific glymphatic subunit of interest. For example, a 20% mechanical strain on capillary basement membranes does not significantly decrease venous efflux (2% decrease in flow rates), while the same magnitude of strain on astrocyte networks and interstitial spaces decreases efflux flow rates by 7% and 22%, respectively. Conclusion: Our simulations reveal that solid stress from brain tumors directly reduces glymphatic fluid transport, independently from biochemical effects from cancer cells. Understanding these pathophysiological implications is crucial for developing targeted interventions aimed at restoring effective waste clearance mechanisms in the brain.This study opens potential avenues for future experimental research in brain tumor-related glymphatic dysfunction.

16.
Chem Sci ; 15(10): 3633-3639, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455008

RESUMO

Fluorescent molecular probes that report nitroreductase activity have promise as imaging tools to elucidate the biology of hypoxic cells and report the past hypoxic history of biomedical tissue. This study describes the synthesis and validation of a "first-in-class" ratiometric, hydrophilic near-infrared fluorescent molecular probe for imaging hypoxia-induced nitroreductase activity in 2D cell culture monolayers and 3D multicellular tumor spheroids. The probe's molecular structure is charge-balanced and the change in ratiometric signal is based on Förster Resonance Energy Transfer (FRET) from a deep-red, pentamethine cyanine donor dye (Cy5, emits ∼660 nm) to a linked near-infrared, heptamethine cyanine acceptor dye (Cy7, emits ∼780 nm). Enzymatic reduction of a 4-nitrobenzyl group on the Cy7 component induces a large increase in Cy7/Cy5 fluorescence ratio. The deep penetration of near-infrared light enables 3D optical sectioning of intact tumor spheroids, and visualization of individual hypoxic cells (i.e., cells with raised Cy7/Cy5 ratio) as a new way to study tumor spheroids. Beyond preclinical imaging, the near-infrared fluorescent molecular probe has high potential for ratiometric imaging of hypoxic tissue in living subjects.

17.
bioRxiv ; 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38405787

RESUMO

Purpose: In many diseases, an overabundance of macrophages contributes to adverse outcomes. While numerous studies have compared macrophage phenotype after mechanical stimulation or with varying local stiffness, it is unclear if and how macrophages themselves contribute to mechanical forces in their microenvironment. Methods: Raw 264.7 murine macrophages were embedded in a confining agarose gel, where they proliferated to form spheroids over time. Gels were synthesized at various concentrations to tune the stiffness and treated with various growth supplements to promote macrophage polarization. The spheroids were then analyzed by immunofluorescent staining and qPCR for markers of proliferation, mechanosensory channels, and polarization. Finally, spheroid geometries were used to computationally model the strain generated in the agarose by macrophage spheroid growth. Results: Macrophages form spheroids and generate growth-induced mechanical forces (i.e., solid stress) within confining agarose gels, which can be maintained for at least 16 days in culture. Increasing agarose concentration restricts spheroid expansion, promotes discoid geometries, limits gel deformation, and induces an increase in iNOS expression. LPS stimulation increases spheroid growth, though this effect is reversed with the addition of IFN-γ. Ki67 expression decreases with increasing agarose concentration, in line with the growth measurements. Conclusions: Macrophages alone both respond to and generate solid stress. Understanding how macrophage generation of growth-induced solid stress responds to different environmental conditions will help to inform treatment strategies for the plethora of diseases that involve macrophage accumulation.

18.
Trends Mol Med ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39142973

RESUMO

Exploring and exploiting the microenvironmental similarities between pulmonary tuberculosis (TB) granulomas and malignant tumors has revealed new strategies for more efficacious host-directed therapies (HDTs). This opinion article discusses a paradigm shift in TB therapeutic development, drawing on critical insights from oncology. We summarize recent efforts to characterize and overcome key shared features between tumors and granulomas, including excessive fibrosis, abnormal angiogenesis, hypoxia and necrosis, and immunosuppression. We provide specific examples of cancer therapy application to TB to overcome these microenvironmental abnormalities, including matrix-targeting therapies, antiangiogenic agents, and immune-stimulatory drugs. Finally, we propose a new framework for combining HDTs with anti-TB agents to maximize therapeutic delivery and efficacy while reducing treatment dosages, duration, and harmful side effects to benefit TB patients.

19.
Cancer Immunol Res ; 12(4): 400-412, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38260999

RESUMO

Intrahepatic cholangiocarcinoma (ICC) has limited therapeutic options and a dismal prognosis. Adding blockade of the anti-programmed cell death protein (PD)-1 pathway to gemcitabine/cisplatin chemotherapy has recently shown efficacy in biliary tract cancers but with low response rates. Here, we studied the effects of anti-cytotoxic T lymphocyte antigen (CTLA)-4 when combined with anti-PD-1 and gemcitabine/cisplatin in orthotopic murine models of ICC. This combination therapy led to substantial survival benefits and reduction of morbidity in two aggressive ICC models that were resistant to immunotherapy alone. Gemcitabine/cisplatin treatment increased tumor-infiltrating lymphocytes and normalized the ICC vessels and, when combined with dual CTLA-4/PD-1 blockade, increased the number of activated CD8+Cxcr3+IFNγ+ T cells. CD8+ T cells were necessary for the therapeutic benefit because the efficacy was compromised when CD8+ T cells were depleted. Expression of Cxcr3 on CD8+ T cells is necessary and sufficient because CD8+ T cells from Cxcr3+/+ but not Cxcr3-/- mice rescued efficacy in T cell‒deficient mice. Finally, rational scheduling of anti-CTLA-4 "priming" with chemotherapy followed by anti-PD-1 therapy achieved equivalent efficacy with reduced overall drug exposure. These data suggest that this combination approach should be clinically tested to overcome resistance to current therapies in ICC patients.


Assuntos
Colangiocarcinoma , Cisplatino , Gencitabina , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/metabolismo , Cisplatino/uso terapêutico , Antígeno CTLA-4/antagonistas & inibidores , Gencitabina/uso terapêutico , Microambiente Tumoral
20.
Cancers (Basel) ; 15(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37444394

RESUMO

Atomic force microscopy (AFM) is a popular tool for evaluating the mechanical properties of biological materials (cells and tissues) at high resolution. This technique has become particularly attractive to cancer researchers seeking to bridge the gap between mechanobiology and cancer initiation, progression, and treatment resistance. The majority of AFM studies thus far have been extensively focused on the nanomechanical characterization of cells. However, these approaches fail to capture the complex and heterogeneous nature of a tumor and its host organ. Over the past decade, efforts have been made to characterize the mechanical properties of tumors and tumor-bearing tissues using AFM. This has led to novel insights regarding cancer mechanopathology at the tissue scale. In this Review, we first explain the principles of AFM nanoindentation for the general study of tissue mechanics. We next discuss key considerations when using this technique and preparing tissue samples for analysis. We then examine AFM application in characterizing the mechanical properties of cancer tissues. Finally, we provide an outlook on AFM in the field of cancer mechanobiology and its application in the clinic.

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