82 research outputs found

    Targeting Angiogenesis-Dependent Calcified Neoplasms Using Combined Polymer Therapeutics

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    There is an immense clinical need for novel therapeutics for the treatment of angiogenesis-dependent calcified neoplasms such as osteosarcomas and bone metastases. We developed a new therapeutic strategy to target bone metastases and calcified neoplasms using combined polymer-bound angiogenesis inhibitors. Using an advanced "living polymerization" technique, the reversible addition-fragmentation chain transfer (RAFT), we conjugated the aminobisphosphonate alendronate (ALN), and the potent anti-angiogenic agent TNP-470 with N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer through a Glycine-Glycine-Proline-Norleucine linker, cleaved by cathepsin K, a cysteine protease overexpressed at resorption sites in bone tissues. In this approach, dual targeting is achieved. Passive accumulation is possible due to the increase in molecular weight following polymer conjugation of the drugs, thus extravasating from the tumor leaky vessels and not from normal healthy vessels. Active targeting to the calcified tissues is achieved by ALN's affinity to bone mineral.The anti-angiogenic and antitumor potency of HPMA copolymer-ALN-TNP-470 conjugate was evaluated both in vitro and in vivo. We show that free and conjugated ALN-TNP-470 have synergistic anti-angiogenic and antitumor activity by inhibiting proliferation, migration and capillary-like tube formation of endothelial and human osteosarcoma cells in vitro. Evaluation of anti-angiogenic, antitumor activity and body distribution of HPMA copolymer-ALN-TNP-470 conjugate was performed on severe combined immunodeficiency (SCID) male mice inoculated with mCherry-labeled MG-63-Ras human osteosarcoma and by modified Miles permeability assay. Our targeted bi-specific conjugate reduced VEGF-induced vascular hyperpermeability by 92% and remarkably inhibited osteosarcoma growth in mice by 96%.This is the first report to describe a new concept of a narrowly-dispersed combined polymer therapeutic designed to target both tumor and endothelial compartments of bone metastases and calcified neoplasms at a single administration. This new approach of co-delivery of two synergistic drugs may have clinical utility as a potential therapy for angiogenesis-dependent cancers such as osteosarcoma and bone metastases

    Lomustine Nanoparticles Enable Both Bone Marrow Sparing and High Brain Drug Levels – A Strategy for Brain Cancer Treatments

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    Purpose The blood brain barrier compromises glioblastoma chemotherapy. However high blood concentrations of lipophilic, alkylating drugs result in brain uptake, but cause myelosuppression. We hypothesised that nanoparticles could achieve therapeutic brain concentrations without dose-limiting myelosuppression. Methods Mice were dosed with either intravenous lomustine Molecular Envelope Technology (MET) nanoparticles (13 mg kg-1) or ethanolic lomustine (6.5 mg kg-1) and tissues analysed. Efficacy was assessed in an orthotopic U-87 MG glioblastoma model, following intravenous MET lomustine (daily 13 mg kg-1) or ethanolic lomustine (daily 1.2 mg kg-1 - the highest repeated dose possible). Myelosuppression and MET particle macrophage uptake were also investigated. Results The MET formulation resulted in modest brain targeting (brain/ bone AUC0-4h ratios for MET and ethanolic lomustine = 0.90 and 0.53 respectively and brain/ liver AUC0-4h ratios for MET and ethanolic lomustine = 0.24 and 0.15 respectively). The MET formulation significantly increased mice (U-87 MG tumours) survival times; with MET lomustine, ethanolic lomustine and untreated mean survival times of 33.2, 22.5 and 21.3 days respectively and there were no material treatment-related differences in blood and femoral cell counts. Macrophage uptake is slower for MET nanoparticles than for liposomes. Conclusions Particulate drug formulations improved brain tumour therapy without major bone marrow toxicity

    6′′‐Thioether Tobramycin Analogues: Towards Selective Targeting of Bacterial Membranes

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91322/1/ange_201200761_sm_miscellaneous_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/91322/2/5750_ftp.pd

    α-Galactosylceramide and peptide-based nano-vaccine synergistically induced a strong tumor suppressive effect in melanoma

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    α-Galactosylceramide (GalCer) is a glycolipid widely known as an activator of Natural killer T (NKT) cells, constituting a promising adjuvant against cancer, including melanoma. However, limited clinical outcomes have been obtained so far. This study evaluated the synergy between GalCer and major histocompatibility complex (MHC) class I and MHC class II melanoma-associated peptide antigens and the Toll-Like Receptor (TLR) ligands CpG and monophosphoryl lipid A (MPLA), which we intended to maximize following their co-delivery by a nanoparticle (NP). This is expected to improve GalCer capture by dendritic cells (DCs) and subsequent presentation to NKT cells, and simultaneously induce an anti-tumor specific T-cell mediated immunity. The combination of GalCer with melanoma peptides and TLR ligands successfully restrained tumor growth. The tumor volume in these animals was 5-fold lower than the ones presented by mice immunized with NPs not containing GalCer. However, tumor growth was controlled at similar levels by GalCer entrapped or in its soluble form, when mixed with antigens and TLR ligands. Those two groups showed an improved infiltration of T lymphocytes into the tumor, but only GalCer-loaded nano-vaccine induced a prominent and enhanced infiltration of NKT and NK cells. In addition, splenocytes of these animals secreted levels of IFN-γ and IL-4 at least 1.5-fold and 2-fold higher, respectively, than those treated with the mixture of antigens and adjuvants in solution. Overall, the combined delivery of the NKT agonist with TLR ligands and melanoma antigens via this multivalent nano-vaccine displayed a synergistic anti-tumor immune-mediated efficacy in B16F10 melanoma mouse model. STATEMENT OF SIGNIFICANCE: Combination of α-galactosylceramide (GalCer), a Natural Killer T (NKT) cell agonist, with melanoma-associated antigens presented by MHC class I (Melan-A:26) and MHC class II (gp100:44) molecules, and Toll-like Receptor (TLR) ligands (MPLA and CpG), within nanoparticle matrix induced a prominent anti-tumor immune response able to restrict melanoma growth. An enhanced infiltration of NKT and NK cells into tumor site was only achieved when the combination GalCer, antigens and TLR ligands were co-delivered by nanovaccine

    Therapeutic targeting of PD-1/PD-L1 blockade by novel small-molecule inhibitors recruits cytotoxic T cells into solid tumor microenvironment

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    © Author(s) (or their employer(s)) 2022.This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See http://creativecommons.org/licenses/by-nc/4.0/.Background: Inhibiting programmed cell death protein 1 (PD-1) or PD-ligand 1 (PD-L1) has shown exciting clinical outcomes in diverse human cancers. So far, only monoclonal antibodies are approved as PD-1/PD-L1 inhibitors. While significant clinical outcomes are observed on patients who respond to these therapeutics, a large proportion of the patients do not benefit from the currently available immune checkpoint inhibitors, which strongly emphasize the importance of developing new immunotherapeutic agents. Methods: In this study, we followed a transdisciplinary approach to discover novel small molecules that can modulate PD-1/PD-L1 interaction. To that end, we employed in silico analyses combined with in vitro, ex vivo, and in vivo experimental studies to assess the ability of novel compounds to modulate PD-1/PD-L1 interaction and enhance T-cell function. Results: Accordingly, in this study we report the identification of novel small molecules, which like anti-PD-L1/PD-1 antibodies, can stimulate human adaptive immune responses. Unlike these biological compounds, our newly-identified small molecules enabled an extensive infiltration of T lymphocytes into three-dimensional solid tumor models, and the recruitment of cytotoxic T lymphocytes to the tumor microenvironment in vivo, unveiling a unique potential to transform cancer immunotherapy. Conclusions: We identified a new promising family of small-molecule candidates that regulate the PD-L1/PD-1 signaling pathway, promoting an extensive infiltration of effector CD8 T cells to the tumor microenvironment.C and RCA are supported by the Fundação para a Ciência e a Tecnologia, Ministério da Ciência, Tecnologia e Ensino Superior (FCT-MCTES) (PhD grants PD/BD/128238/2016 (RCA) and SFRH/BD/131969/2017 (BC)). The authors thank the funding received from the European Structural & Investment Funds through the COMPETE Programme and from National Funds through FCT under the Programme grant LISBOA-01-0145-FEDER016405 - SAICTPAC/0019/2015 (HF and RCG). HFF and RCA received additional support from FCT-MCTES (UIDB/04138/2020, PTDC/BTM-SAL/4350/2021 and UTAPEXPL/NPN/0041/2021; EXPL/MED-QUI/1316/2021, respectively). The MultiNano@MBM project was supported by The Israeli Ministry of Health, and FCTMCTES, under the frame of EuroNanoMed-II (ENMed/0051/2016; HF and RS-F). HF and RS-F thank the generous financial support from ‘La Caixa’ Foundation under the framework of the Healthcare Research call 2019 (NanoPanther; LCF/PR/HR19/52160021), as well as CaixaImpulse (Co-Vax; LCF/TR/CD20/52700005). MP thanks the financial support from Liga Portuguesa Contra o Cancro – Nucleo Regional do Sul and ‘iNOVA4Health – UIDB/04462/2020’, a program financially supported by Fundação para a Ciência e Tecnologia/Ministério da Educação e Ciência. RS-F thanks the following funding agencies for their generous support: the European Research Council (ERC) Advanced Grant Agreement No. (835227)–3DBrainStrom, ERC PoC Grant Agreement no. 862580 – 3DCanPredict, The Israel Science Foundation (Grant No. 1969/18), The Melanoma Research Alliance (MRA Established Investigator Award n°615808), the Israel Cancer Research Fund (ICRF) Professorship award (n° PROF-18-682), and the Morris Kahn Foundation.info:eu-repo/semantics/publishedVersio

    Judah Folkman, a pioneer in the study of angiogenesis

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    More than 30 years ago, Judah Folkman found a revolutionary new way to think about cancer. He postulated that in order to survive and grow, tumors require blood vessels, and that by cutting off that blood supply, a cancer could be starved into remission. What began as a revolutionary approach to cancer has evolved into one of the most exciting areas of scientific inquiry today. Over the years, Folkman and a growing team of researchers have isolated the proteins and unraveled the processes that regulate angiogenesis. Meanwhile, a new generation of angiogenesis research has emerged as well, widening the field into new areas of human disease and deepening it to examine the underlying biological processes responsible for those diseases

    Exploiting nanotechnology to target cancer

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    Nanotechnology is increasingly finding use in the management of cancer. Nanoscale devices have impacted cancer biology at three levels: early detection using, for example, nanocantilevers or nanoparticles; tumour imaging using radiocontrast nanoparticles or quantum dots; and drug delivery using nanovectors and hybrid nanoparticles. This review addresses some of the major milestones in the integration of nanotechnology and cancer biology, and the future of nanoscale approaches for cancer management
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