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1.
Mol Imaging Biol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649626

RESUMO

This MIB guide briefly summarizes the generation of patient-derived xenografts (PDXs) and highlights the importance of validating PDX models for the presence of B cell lymphoma of human origin before their use in radiotheranostic applications. The use of this protocol will allow researchers to learn different methods for screening PDX models for Epstein-Barr virus (EBV)-infected B cell lymphoma.

2.
bioRxiv ; 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37986985

RESUMO

Antibody-drug conjugates (ADCs) have emerged as promising therapeutics for cancer treatment; however, their effectiveness has been limited by single antigen targeting, potentially leading to resistance mechanisms triggered by tumor compensatory pathways or reduced expression of the target protein. Here, we present antibody-ADC click, an approach that harnesses bioorthogonal click chemistry for in vivo dual receptor targeting, irrespective of the levels of the tumor's expression of the ADC-targeting antigen. Antibody-ADC click enables targeting heterogeneity and enhances antibody internalization and drug delivery inside cancer cells, resulting in potent toxicity. We conjugated antibodies and ADCs to the bioorthogonal click moieties tetrazine (Tz) and trans-cyclooctene (TCO). Through sequential antibody administration in living biological systems, we achieved dual receptor targeting by in vivo clicking of antibody-TCO with antibody-Tz. We show that the clicked antibody therapy outperformed conventional ADC monotherapy or antibody combinations in preclinical models mimicking ADC-eligible, ADC-resistant, and ADC-ineligible tumors. Antibody-ADC click enables in vivo dual-antigen targeting without extensive antibody bioengineering, sustains tumor treatment, and enhances antibody-mediated cytotoxicity.

3.
ACS Omega ; 8(39): 35884-35892, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37810678

RESUMO

Previous studies have suggested tumoral caveolin-1 (CAV1) as a predictive biomarker for the response to anti-HER2 antibody drug therapies in gastric tumors. In this study, radiolabeled and fluorescently labeled anti-CAV1 antibodies were developed and tested as an immunoPET or optical imaging agent to detect CAV1 in HER2-positive/CAV1-high NCIN87 gastric tumors. The expression of CAV1 receptors in NCIN87 gastric tumors and nontumor murine organs was determined by Western blot. Binding assays were performed to validate the anti-CAV1 antibody specificity for CAV1-expressing NCIN87 cancer cells. Subcutaneous and orthotopic NCIN87 xenografts were used for PET imaging and ex vivo biodistribution of the radioimmunoconjugate. Additional HER2-PET and CAV1-optical imaging was also performed to determine CAV1 in the HER2-positive tumors. 89Zr-labeled anti-CAV1 antibody was able to bind to CAV1-expressing NCIN87 cells with a Bmax value of 2.7 × 103 CAV1 receptors/cell in vitro. ImmunoPET images demonstrated the localization of the antibody in subcutaneous NCIN87 xenografts. In the orthotopic model, CAV1 expression was also observed by optical imaging in the HER2-positive tumors previously imaged with HER2-PET. Ex vivo biodistribution analysis further confirmed these imaging results. The preclinical data from this study demonstrate the potential of using CAV1-PET and optical imaging for detecting gastric tumors.

4.
J Nucl Med ; 64(8): 1195-1202, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37268425

RESUMO

Metformin has effects beyond its antihyperglycemic properties, including altering the localization of membrane receptors in cancer cells. Metformin decreases human epidermal growth factor receptor (HER) membrane density. Depletion of cell-surface HER decreases antibody-tumor binding for imaging and therapeutic approaches. Here, we used HER-targeted PET to annotate antibody-tumor binding in mice treated with metformin. Methods: Small-animal PET annotated antibody binding in HER-expressing xenografts on administration of an acute versus a daily dose schedule of metformin. Analyses at the protein level in the total, membrane, and internalized cell extracts were performed to determine receptor endocytosis, HER surface and internalized protein levels, and HER phosphorylation. Results: At 24 h after injection of radiolabeled anti-HER antibodies, control tumors had higher antibody accumulation than tumors treated with an acute dose of metformin. These differences were temporal, and by 72 h, tumor uptake in acute cohorts was similar to uptake in control. Additional PET imaging revealed a sustained decrease in tumor uptake on daily metformin treatment compared with control and acute metformin cohorts. The effects of metformin on membrane HER were reversible, and after its removal, antibody-tumor binding was restored. The time- and dose-dependent effects of metformin-induced HER depletion observed preclinically were validated with immunofluorescence, fractionation, and protein analysis cell assays. Conclusion: The findings that metformin decreases cell-surface HER receptors and reduces antibody-tumor binding may have significant implications for the use of antibodies targeting these receptors in cancer treatment and molecular imaging.


Assuntos
Metformina , Neoplasias , Humanos , Animais , Camundongos , Anticorpos Monoclonais/uso terapêutico , Metformina/farmacologia , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores ErbB/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Linhagem Celular Tumoral
5.
J Nucl Med ; 64(10): 1638-1646, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37385676

RESUMO

The human epidermal growth factor receptor 2 (HER2)-targeting trastuzumab emtansine (T-DM1) and trastuzumab deruxtecan (T-DXd) are antibody-drug conjugates (ADC) clinically used to treat HER2-positive breast cancer, with the latter receiving clinical approval in 2021 for HER2-positive gastric cancer. Lovastatin, a cholesterol-lowering drug, temporally elevates cell-surface HER2 in ways that enhance HER2-ADC binding and internalization. Methods: In an NCIN87 gastric xenograft model and a gastric patient-derived xenograft model, we used the 89Zr-labeled or 64Cu-labeled anti-HER2 antibody trastuzumab to investigate the dosing regimen of ADC therapy with and without coadministration of lovastatin. We compared the ADC efficacy of a multiple-dose ADC regime, which replicates the clinical dose regimen standard, with a single-dose regime. Results: T-DM1/lovastatin treatment inhibited tumor growth, regardless of multiple- or single-dose T-DM1 administration. Coadministration of lovastatin with T-DM1 or T-DXd as a single dose enhanced tumor growth inhibition, which was accompanied by a decrease in signal on HER2-targeted immuno-PET and a decrease in HER2-mediated signaling at the cellular level. DNA damage signaling was increased on ADC treatment in vitro. Conclusion: Our data from a gastric cancer xenograft show the utility of HER2-targeted immuno-PET to inform the tumor response to ADC therapies in combination with modulators of cell-surface target availability. Our studies also demonstrate that statins enhance ADC efficacy in both a cell-line and a patient-derived xenograft model in ways that enable a single-dose administration of the ADC.


Assuntos
Neoplasias da Mama , Inibidores de Hidroximetilglutaril-CoA Redutases , Imunoconjugados , Neoplasias Gástricas , Humanos , Feminino , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Anticorpos Monoclonais Humanizados/farmacologia , Linhagem Celular Tumoral , Trastuzumab , Ado-Trastuzumab Emtansina/farmacologia , Ado-Trastuzumab Emtansina/uso terapêutico , Receptor ErbB-2/metabolismo , Neoplasias da Mama/patologia , Imunoconjugados/uso terapêutico , Tomografia por Emissão de Pósitrons , Lovastatina/farmacologia , Lovastatina/uso terapêutico
6.
Proc Natl Acad Sci U S A ; 120(14): e2220413120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36972439

RESUMO

Human epidermal growth factor receptor 2 (HER2) is overexpressed in various cancer types. HER2-targeting trastuzumab plus chemotherapy is used as first-line therapy for HER2-positive recurrent or primary metastatic gastric cancer, but intrinsic and acquired trastuzumab resistance inevitably develop over time. To overcome gastric cancer resistance to HER2-targeted therapies, we have conjugated trastuzumab with a beta-emitting therapeutic isotope, lutetium-177, to deliver radiation locally to gastric tumors with minimal toxicity. Because trastuzumab-based targeted radioligand therapy (RLT) requires only the extramembrane domain binding of membrane-bound HER2 receptors, HER2-targeting RLT can bypass any resistance mechanisms that occur downstream of HER2 binding. Leveraging our previous discoveries that statins, a class of cholesterol-lowering drugs, can enhance the cell surface-bound HER2 to achieve effective drug delivery in tumors, we proposed that the combination of statins and [177Lu]Lu-trastuzumab-based RLT can enhance the therapeutic efficacy of HER2-targeted RLT in drug-resistant gastric cancers. We demonstrate that lovastatin elevates cell surface HER2 levels and increases the tumor-absorbed radiation dose of [177Lu]Lu-DOTA-trastuzumab. Furthermore, lovastatin-modulated [177Lu]Lu-DOTA-trastuzumab RLT durably inhibits tumor growth and prolongs overall survival in mice bearing NCI-N87 gastric tumors and HER2-positive patient-derived xenografts (PDXs) of known clinical resistance to trastuzumab therapy. Statins also exhibit a radioprotective effect, reducing radiotoxicity in a mice cohort given the combination of statins and [177Lu]Lu-DOTA-trastuzumab. Since statins are commonly prescribed to patients, our results strongly support the feasibility of clinical studies that combine lovastatin with HER2-targeted RLT in HER2-postive patients and trastuzumab-resistant HER2-positive patients.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Gástricas , Humanos , Animais , Camundongos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Preparações Farmacêuticas , Receptor ErbB-2/metabolismo , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Lovastatina/farmacologia , Lovastatina/uso terapêutico , Linhagem Celular Tumoral
7.
Nat Commun ; 13(1): 2526, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534471

RESUMO

Resistance mechanisms and heterogeneity in HER2-positive gastric cancers (GC) limit Trastuzumab benefit in 32% of patients, and other targeted therapies have failed in clinical trials. Using patient samples, patient-derived xenografts (PDXs), partially humanized biological models, and HER2-targeted imaging technologies we demonstrate the role of caveolin-1 (CAV1) as a complementary biomarker in GC selection for Trastuzumab therapy. In retrospective analyses of samples from patients enrolled on Trastuzumab trials, the CAV1-high profile associates with low membrane HER2 density and low patient survival. We show a negative correlation between CAV1 tumoral protein levels - a major protein of cholesterol-rich membrane domains - and Trastuzumab-drug conjugate TDM1 tumor uptake. Finally, CAV1 depletion using knockdown or pharmacologic approaches (statins) increases antibody drug efficacy in tumors with incomplete HER2 membranous reactivity. In support of these findings, background statin use in patients associates with enhanced antibody efficacy. Together, this work provides preclinical justification and clinical evidence that require prospective investigation of antibody drugs combined with statins to delay drug resistance in tumors.


Assuntos
Neoplasias da Mama , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Gástricas , Neoplasias da Mama/tratamento farmacológico , Caveolina 1/genética , Caveolina 1/metabolismo , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Estudos Prospectivos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico
8.
Nucl Med Biol ; 108-109: 70-75, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35339065

RESUMO

Targeted tumor therapies of receptor tyrosine kinases (RTK) do not work for every patient with cancer, owing to differences in the level of RTK heterogeneity, RTK co-activation mechanisms, and other aspects of disease biology. Over the last years, the combination of non-invasive positron emission tomography (PET) with non-pharmacological doses of an RTK-specific antibody has shown the ability to study cancer biology in real-time and in the whole body of living subjects at the early stages of the disease and in response to therapies. Many RTK-specific antibody-PET imaging conjugates exist in the clinics and show potential for earlier diagnosis and accurate management of oncology patients. Herein, our review concisely focuses on clinical and preclinical data of RTK-targeted PET imaging to detect two significant biological mechanisms of tumor resistance - RTK heterogeneity and RTK co-activation. This mini-review provides an overview of RTK-targeted PET imaging studies of the last 4 years and gives collective information on how it may assist prognostic information and image disease recurrence.


Assuntos
Neoplasias , Receptores Proteína Tirosina Quinases , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Tomografia por Emissão de Pósitrons/métodos , Receptores Proteína Tirosina Quinases/uso terapêutico
9.
Mol Imaging Biol ; 24(4): 519-525, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35301641

RESUMO

Mentorship is a fundamental aspect that contributes to the success of a career in science, technology, engineering, and mathematics (STEM), particularly in academia. Research suggests that underrepresented minorities (URMs) often experience less quality mentorship and face barriers to finding successful mentor-mentee relationships. URM trainees in STEM face challenges that are not encountered by their majority peers or mentors, adding another level of complexity to establishing important relationships. Mentors of URM trainees must therefore mentor beyond general scientific training and tailor their mentorship to be more culturally appropriate and inclusive, allowing URM trainees to bring their whole selves to the table and leading to their effective socialization. Herein, we present the perspectives of group leaders and trainees from around the globe to highlight key aspects of creating successful mentor-mentee relationships that are sustainable and productive for both parties.


Assuntos
Engenharia , Mentores , Humanos , Tecnologia
10.
Mol Imaging Biol ; 24(4): 511-518, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35147837

RESUMO

PURPOSE: Immuno-positron emission tomography (immunoPET) combines the specificity of an antibody with the sensitivity of PET to image dysregulated pathways in cancer. This study examines the performance of immunoPET using the radioimmunoconjugate [89Zr]Zr-DFO-Panitumumab to detect epidermal growth factor receptor (EGFR) expression in an orthotopic model of bladder cancer (BCa). PROCEDURES: Expression and quantification of EGFR receptors were confirmed in four different BCa cell lines. Binding assays validated [89Zr]Zr-DFO-Panitumumab specificity for EGFR-expressing UMUC3 BCa cells. Subcutaneous and orthotopic UMUC3 xenografts were then used for PET imaging and ex vivo biodistribution of the radioimmunoconjugate. Control cohorts included non-tumor mice, 89Zr-labeled non-specific IgG, and blocking experiments. RESULTS: [89Zr]Zr-DFO-Panitumumab binds specifically to EGFR-expressing UMUC3 cells with a Bmax value of 5.9 × 104 EGFRs/cell in vitro. ImmunoPET/CT images show localization of the antibody in subcutaneous UMUC3 xenografts and murine bladder tumors. In the orthotopic model, the immunoPET signal correlates with the respective tumor volume. Ex vivo biodistribution analysis further confirmed imaging results. CONCLUSION: The preclinical data presents a proof of concept for utilizing EGFR-targeted immunoPET to image BCa with altered EGFR protein levels.


Assuntos
Imunoconjugados , Neoplasias da Bexiga Urinária , Animais , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Camundongos , Panitumumabe , Tomografia por Emissão de Pósitrons/métodos , Distribuição Tecidual , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Zircônio
11.
J Mater Chem B ; 10(17): 3248-3259, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35084012

RESUMO

Mesoporous silica nanoparticles (MSNPs) have attracted much attention in many biomedical applications. One of the fields in which smart functional nanosystems have found wide application is cancer treatment. Here, we present new silica nanoparticle-based systems which have been explored as efficient vehicles to transport and deliver photosensitizers (PSs) into tumor tissues during photodynamic therapy (PDT). In this work, we report the preparation, characterization, and in vitro studies of distinct shaped MSNPs grafted with S-glycoside porphyrins (Pors). The ensuing nanomaterials were fully characterized, and their properties as third-generation PSs for PDT against two bladder cancer cell lines, HT-1376 and UM-UC-3, were examined. The best uptake results were obtained for MSNP-PS2, while MSNP-PS1 showed the lowest cellular uptake among the nanocarriers tested, but revealed the best phototoxicity in both cancer cells. Overall, the phototoxicity was higher with MSNPs than with mesoporous silica nanorods (MSNRs) and higher uptake and phototoxicity were consistently observed in UM-UC-3 rather than in HT-1376 cancer cells.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Porosidade , Dióxido de Silício
12.
Mol Imaging Biol ; 23(3): 301-309, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33754293

RESUMO

Recent events in America in 2020 have stimulated a worldwide movement to dismantle anti-Black racism in all facets of our lives. Anti-Black racism is, as defined by the Movement for Black Lives, a "term used to specifically describe the unique discrimination, violence, and harm imposed on and impacting Black people specifically." In science, technology, engineering, and mathematics (STEM), we have yet to achieve the goal and responsibility to ensure that the field reflects the diversity of our lived experiences. Members of the Women in Molecular Imaging Network (WIMIN) have come together to take a stand on diversity, equity, and inclusion in the field of molecular imaging. We strongly condemn oppression in all its forms and strive to identify and dismantle barriers that lead to inequities in the molecular imaging community and STEM as a whole. In this series coined "Visions" (Antiracism and Allyship in Action), we identify and discuss specific actionable items for improving diversity and representation in molecular imaging and ensuring inclusion of all members of the community, inclusive of race, disability, ethnicity, religion, or LGBTQ+ identity. Although the issues highlighted here extend to other under-recruited and equity-seeking groups, for this first article, we are focusing on one egregious and persistent form of discrimination: anti-Black racism. In this special article, Black women residing in America present their lived experiences in the molecular imaging field and give candid insights into the challenges, frustrations, and hopes of our Black friends and colleagues. While this special article focuses on the experiences of Black women, we would like the readers to reflect on their anti-Blackness toward men, transgender, nonbinary, and gender non-conforming people. From the vulnerability we have asked of all our participants, these stories are meant to inspire and invoke active antiracist work among the readership. We present strategies for dismantling systemic racism that research centers and universities can implement in the recruitment, retention, mentorship, and development of Black trainees and professionals. We would like to specifically acknowledge the Black women who took the time to be interviewed, write perspectives, and share their lived experiences in hopes that it will inspire genuine and lasting change.


Assuntos
Imagem Molecular , Racismo , Racismo Sistêmico , Negro ou Afro-Americano , Escolha da Profissão , Comportamento Cooperativo , Diversidade Cultural , Engenharia , Feminino , Humanos , Masculino , Estados Unidos
13.
J Nucl Med ; 62(3): 366-371, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32646879

RESUMO

Receptor tyrosine kinase (RTK) coexpression facilitates tumor resistance due to redundancies in the phosphatidylinositol-3'-kinase/protein kinase B and KRAS/extracellular-signal-regulated kinase signaling pathways, among others. Crosstalk between the oncogenic RTK hepatocyte growth factor receptor (MET), epidermal growth factor receptor (EGFR), and human epidermal growth factor receptor 2 (HER2) are involved in tumor resistance to RTK-targeted therapies. Methods: In a relevant renal cell carcinoma patient-derived xenograft model, we use the 89Zr-labeled anti-RTK antibodies (immuno-PET) onartuzumab, panitumumab, and trastuzumab to monitor MET, EGFR, and HER2 protein levels, respectively, during treatment with agents to which the model was resistant (cetuximab) or sensitive (INC280 and trametinib). Results: Cetuximab treatment resulted in continued tumor growth, as well as an increase in all RTK protein levels at the tumor in vivo on immuno-PET and ex vivo at the cellular level. Conversely, after dual MET/mitogen-activated protein kinase inhibition, tumor growth was significantly blunted and corresponded to a decrease in RTK levels. Conclusion: These data show the utility of RTK-targeted immuno-PET to annotate RTK changes in protein expression and inform tumor response to targeted therapies.


Assuntos
Regulação Neoplásica da Expressão Gênica , Tomografia por Emissão de Pósitrons , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-ret/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Marcação por Isótopo , Proteínas Proto-Oncogênicas c-ret/imunologia , Radioisótopos , Zircônio
14.
Molecules ; 25(20)2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33050602

RESUMO

The specificity of antibodies for antigens overexpressed or uniquely expressed in tumor cells makes them ideal candidates in the development of bioconjugates for tumor imaging. Molecular imaging can aid clinicians in the diagnosis of gastric tumors and in selecting patients for therapies targeting receptors with a heterogeneous intratumoral or intertumoral expression. Antibodies labeled with an imaging radiometal can be used to detect primary tumors and metastases using whole-body positron emission tomography (PET) or single photon emission computed tomography (SPECT), both during diagnosis and monitoring disease response. Conjugated with fluorescent dyes, antibodies can image tumors by targeted optical imaging. This review provides an overview of the most recent advances in the use of antibodies labeled with radiometals or conjugated with fluorescent dyes for gastric cancer imaging.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Humanos , Imagem Óptica/métodos
15.
Clin Cancer Res ; 26(23): 6215-6229, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32998959

RESUMO

PURPOSE: Statins are cholesterol-depleting drugs used to treat patients with hypercholesterolemia. Preclinically, statins disrupt trafficking of receptors present at the cell membrane. Membrane receptors, defined as tumor biomarkers and therapeutic targets, are often internalized by an endocytic pathway. Indeed, receptor endocytosis and recycling are dynamic mechanisms that often affect receptor density at the cell surface. In therapies using monoclonal antibodies (mAb), a downregulation in receptor density at the cell surface decreases antibody binding to the extracellular domain of the membrane receptor. Here, we determined the potential of lovastatin, simvastatin, and rosuvastatin in preclinically modulating epidermal growth factor receptor (EGFR) and prostate-specific membrane antigen (PSMA) receptor density at the tumor cell surface. EXPERIMENTAL DESIGN: Small-animal PET was used to study the binding of 89Zr-labeled antibodies in ectopic xenografts. Ex vivo analyses were performed to determine changes in endocytic proteins, EGFR, and PSMA surface levels. RESULTS: Acute statin treatment using lovastatin, simvastatin, or rosuvastatin enhanced tumors' avidity for the mAbs panitumumab, cetuximab, and huJ591. Statins temporarily modulated caveolin-1, cavin-1, endophilin, clathrin, and dynamin proteins in EGFR- and PSMA-overexpressing xenografts. CONCLUSIONS: These data show the potential of statins as pharmacologic modulators of endocytic proteins for improved tumors' accumulation of mAbs. The translational significance of these findings lies in the potential of statins to temporarily modulate the heterogeneous presence of receptors at the cell membrane, a characteristic often associated with poor response in tumors to therapeutic antibodies.


Assuntos
Anticorpos Monoclonais/metabolismo , Antígenos de Superfície/metabolismo , Antineoplásicos/metabolismo , Glutamato Carboxipeptidase II/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Animais , Apoptose , Proliferação de Células , Receptores ErbB/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Nanoscale ; 12(37): 19088-19092, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32955076

RESUMO

Spheroids recapitulate the organization, heterogeneity and microenvironment of solid tumors. Herein, we targeted spatiotemporally the accelerated metabolism of proliferative cells located on the spheroid surface that ensure structure maintenance and/or growth. We demonstrate that phosphorylated carbohydrate amphiphile acts as a potent antimetabolite due to glycolysis inhibition and to in situ formation of supramolecular net around spheroid surface where alkaline phosphatase is overexpressed. The efficiency of the treatment is higher in spheroids as compared to the conventional 2D cultures because of the 2-fold higher expression of glucose transporter 1 (GLUT1). Moreover, treated spheroids do not undergo following relapse.


Assuntos
Neoplasias , Esferoides Celulares , Carboidratos , Humanos , Recidiva , Microambiente Tumoral
17.
Mol Pharm ; 17(6): 2145-2154, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32339462

RESUMO

Photodynamic therapy (PDT) has demonstrated encouraging anticancer therapeutic results, but the current clinically approved photosensitizers (PSs) are not ideal in the treatment of bladder cancer. Conventional PSs have low selectivity to the bladder tumor tissue and induce toxicity or bystander effects on nontumor urothelium. Previous studies demonstrated that the use of galactose-photosensitizer (PS) conjugates is a more selective method of delivering PDT-mediated toxicity due to their ability to recognize carbohydrate-binding domains overexpressed in bladder tumors. Using patient-derived bladder tumor specimens cultured ex vivo and bladder cancer cell lines with different PDT sensitivity, we find that a galactose-phthalocyanine (PcGal16) accumulates in bladder tumors expressing galactose-binding proteins and internalizes through an endocytic process. The endocytosis mechanism is cell line-dependent. In HT-1376 bladder cancer lines resistant to PDT, depletion of caveolin-1-the main structural protein of caveolae structures-increased the amount of sugar-binding proteins, i.e. GLUT1, at the cell membrane resulting in an improved PcGal16 uptake and PDT efficacy. These data show the potential of ex vivo cultures of bladder cancer, that ideally could mimic the original microenvironment, in screening galacto-PDT agents. Additionally, our studies demonstrate that PDT efficacy in bladder cancer depends on the endocytic mechanisms that regulate PS accumulation and internalization in cancer cells.


Assuntos
Caveolina 1/metabolismo , Indóis/química , Indóis/uso terapêutico , Fotoquimioterapia/métodos , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/terapia , Idoso , Western Blotting , Caveolina 1/genética , Linhagem Celular Tumoral , Endocitose/efeitos dos fármacos , Feminino , Galectina 1/genética , Galectina 1/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Técnicas In Vitro , Isoindóis , Masculino , Microscopia de Fluorescência
18.
Cancer Res ; 80(8): 1681-1692, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32086240

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is highly resistant to radiotherapy, chemotherapy, or a combination of these modalities, and surgery remains the only curative intervention for localized disease. Although cancer-associated fibroblasts (CAF) are abundant in PDAC tumors, the effects of radiotherapy on CAFs and the response of PDAC cells to radiotherapy are unknown. Using patient samples and orthotopic PDAC biological models, we showed that radiotherapy increased inducible nitric oxide synthase (iNOS) in the tumor tissues. Mechanistic in vitro studies showed that, although undetectable in radiotherapy-activated tumor cells, iNOS expression and nitric oxide (NO) secretion were significantly increased in CAFs secretome following radiotherapy. Culture of PDAC cells with conditioned media from radiotherapy-activated CAFs increased iNOS/NO signaling in tumor cells through NF-κB, which, in turn, elevated the release of inflammatory cytokines by the tumor cells. Increased NO after radiotherapy in PDAC contributed to an acidic microenvironment that was detectable using the radiolabeled pH (low) insertion peptide (pHLIP). In murine orthotopic PDAC models, pancreatic tumor growth was delayed when iNOS inhibition was combined with radiotherapy. These data show the important role that iNOS/NO signaling plays in the effectiveness of radiotherapy to treat PDAC tumors. SIGNIFICANCE: A radiolabeled pH-targeted peptide can be used as a PET imaging tool to assess therapy response within PDAC and blocking iNOS/NO signaling may improve radiotherapy outcomes.


Assuntos
Fibroblastos Associados a Câncer/efeitos da radiação , Carcinoma Ductal Pancreático/radioterapia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Neoplasias Pancreáticas/radioterapia , Animais , Fibroblastos Associados a Câncer/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Meios de Cultivo Condicionados , Citocinas/metabolismo , Humanos , Camundongos , NF-kappa B/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Resultado do Tratamento , Microambiente Tumoral
19.
J Nucl Med ; 61(9): 1369-1375, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32005776

RESUMO

Galectins are carbohydrate-binding proteins overexpressed in bladder cancer (BCa) cells. Dendritic galactose moieties have a high affinity for galectin-expressing tumor cells. We radiolabeled a dendritic galactose carbohydrate with 18F (18F-labeled galactodendritic unit 4) and examined its potential in imaging urothelial malignancies. Methods: The 18F-labeled first-generation galactodendritic unit 4 was obtained from its tosylate precursor. We conducted in vivo studies in a galectin-expressing UMUC3 orthotopic BCa model to determine the ability of 18F-labeled galactodendritic unit 4 to image BCa. Results: Intravesical administration of 18F-labeled galactodendritic unit 4 allowed specific accumulation of the carbohydrate radiotracer in galectin-1-overexpressing UMUC3 orthotopic tumors when imaged with PET. The 18F-labeled galactodendritic unit 4 was not found to accumulate in nontumor murine bladders. Conclusion: The 18F-labeled galactodendritic unit 4 and similar analogs may be clinically relevant and exploitable for PET imaging of galectin-1-overexpressing bladder tumors.


Assuntos
Radioisótopos de Flúor/química , Galactose/química , Galectina 1/metabolismo , Regulação Neoplásica da Expressão Gênica , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Galactose/farmacocinética , Humanos , Marcação por Isótopo , Camundongos , Radioquímica , Distribuição Tecidual , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
20.
Chem Sci ; 11(14): 3737-3744, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-34094062

RESUMO

We report on aromatic N-glucosides that inhibit selectively the cancer metabolism via two coexistent mechanisms: by initial deprivation of the glucose uptake through competitive binding in the glucose binding pocket of GLUT1 and by formation of a sequestering nanoscale supramolecular network at the cell surface through localized (biocatalytic) self-assembly. We demonstrate that the expression of the cancer associated GLUT1 and alkaline phosphatase are crucial for the effectiveness of this combined approach: cancer cells that overexpress both proteins are prompter to cell death when compared to GLUT1 overexpressing cells. Overall, we showcase that the synergism between physical and biochemical deprivation of cancer metabolism is a powerful approach for development of effective anticancer therapies.

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