Fluorescence-based contrast agents enable real-time detection of solid tumors and their neovasculature, making them ideal for use in image-guided surgery. Several agents have entered late-stage clinical trials or secured FDA approval, suggesting they are likely to become the standard of care in cancer surgeries. One of the key parameters to optimize in contrast agents is molecular size, which dictates much of the pharmacokinetic and pharmacodynamic properties of the agent. Here, we describe the development of a class of protease-activated quenched fluorescent probes in which a N-(2-hydroxypropyl)methacrylamide copolymer is used as the primary scaffold. This copolymer core provides a high degree of probe modularity to generate structures that cannot be achieved with small molecules and peptide probes. We used a previously validated cathepsin substrate and evaluated the effects of length and type of linker, as well as the positioning of the fluorophore/quencher pair on the polymer core. We found that the polymeric probes could be optimized to achieve increased overall signal and tumor-to-background ratios compared to the reference small molecule probe. Our results also revealed multiple structure-activity relationship trends that can be used to design and optimize future optical imaging probes. Furthermore, they confirm that a hydrophilic polymer is an ideal scaffold for use in optical imaging contrast probes, allowing a highly modular design that enables efficient optimization to maximize probe accumulation and overall biodistribution properties.

• Klíčová slova
• HPMA copolymer, cancer, fluorescence, iBody, imaging, protease,
• MeSH
• akrylamidy chemie   MeSH
• fluorescenční barviva * chemie   chemická syntéza   MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory * diagnostické zobrazování   MeSH
• optické zobrazování metody   MeSH
• polymery chemie   MeSH
• proteasy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• akrylamidy MeSH
• fluorescenční barviva * MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• polymery MeSH
• proteasy MeSH

Fluorescence-based contrast agents enable real-time detection of solid tumors and their neovasculature, making them ideal for use in image-guided surgery. Several agents have entered late-stage clinical trials or secured FDA approval, suggesting they are likely to become standard of care in cancer surgeries. One of the key parameters to optimize in contrast agent is molecular size, which dictates much of the pharmacokinetic and pharmacodynamic properties of the agent. Here, we describe the development of a class of protease-activated quenched fluorescent probes in which a N-(2-hydroxypropyl)methacrylamide copolymer is used as the primary scaffold. This copolymer core provides a high degree of probe modularity to generate structures that cannot be achieved with small molecules and peptide probes. We used a previously validated cathepsin substrate and evaluated the effects of length and type of linker as well as positioning of the fluorophore/quencher pair on the polymer core. We found that the polymeric probes could be optimized to achieve increased over-all signal and tumor-to-background ratios compared to the reference small molecule probe. Our results also revealed multiple structure-activity relationship trends that can be used to design and optimize future optical imaging probes. Furthermore, they confirm that a hydrophilic polymer is an ideal scaffold for use in optical imaging contrast probes, allowing a highly modular design that enables efficient optimization to maximize probe accumulation and overall biodistribution properties.

• Klíčová slova
• HPMA copolymer, cancer, fluorescence, iBody, imaging, protease,
• Publikační typ
• časopisecké články MeSH
• preprinty MeSH

Peptide display methods are a powerful tool for discovering new ligands of pharmacologically relevant targets. However, the selected ligands often suffer from low affinity. Using phage display, we identified a new bicyclic peptide binder of prostate-specific membrane antigen (PSMA), a metalloprotease frequently overexpressed in prostate cancer. We show that linking multiple copies of a selected low-affinity peptide to a biocompatible water-soluble N-(2-hydroxypropyl)methacrylamide copolymer carrier (iBody) improved binding of the conjugate by several orders of magnitude. Furthermore, using ELISA, enzyme kinetics, confocal microscopy, and other approaches, we demonstrate that the resulting iBody can distinguish between different conformations of the target protein. The possibility to develop stable, fully synthetic, conformation-selective antibody mimetics has potential applications for molecular recognition, diagnosis and treatment of many pathologies. This strategy could significantly contribute to more effective drug discovery and design.

• Klíčová slova
• HPMA copolymer, PSMA, antibody mimetics, bicyclic phage display, chemical biology, cyclic peptide, molecular recognition, nanotechnology, phage display, protein targeting,
• MeSH
• biomimetické materiály chemie   MeSH
• kalikreiny chemie   MeSH
• lidé MeSH
• nosiče léků chemie   MeSH
• peptidová knihovna * MeSH
• prostatický specifický antigen chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kalikreiny MeSH
• KLK3 protein, human MeSH Prohlížeč
• nosiče léků MeSH
• peptidová knihovna * MeSH
• prostatický specifický antigen MeSH

The proline-specific serine protease fibroblast activation protein (FAP) can participate in the progression of malignant tumors and represents a potential diagnostic and therapeutic target. Recently, we demonstrated an increased expression of FAP in glioblastomas, particularly those of the mesenchymal subtype. Factors controlling FAP expression in glioblastomas are unknown, but evidence suggests that transforming growth factor beta (TGFbeta) can trigger mesenchymal changes in these tumors. Here, we investigated whether TGFbeta promotes FAP expression in transformed and stromal cells constituting the glioblastoma microenvironment. We found that both FAP and TGFbeta-1 are upregulated in glioblastomas and display a significant positive correlation. We detected TGFbeta-1 immunopositivity broadly in glioblastoma tissues, including tumor parenchyma regions in the immediate vicinity of FAP-immunopositive perivascular stromal cells. Wedemonstrate for the first time that TGFbeta-1 induces expression of FAP in non-stem glioma cells, pericytes, and glioblastoma-derived endothelial and FAP+ mesenchymal cells, but not in glioma stem-like cells. In glioma cells, this effect is mediated by the TGFbeta type I receptor and canonical Smad signaling and involves activation of FAP gene transcription. We further present evidence of FAP regulation by TGFbeta-1 secreted by glioma cells. Our results provide insight into the previously unrecognized regulation of FAP expression by autocrine and paracrine TGFbeta-1 signaling in a broad spectrum of cell types present in the glioblastoma microenvironment.

• Klíčová slova
• Smad2, fibroblast activation protein, glioblastoma, regulation of expression, seprase, signaling, transforming growth factor beta, tumor microenvironment,
• MeSH
• endopeptidasy genetika   metabolismus   MeSH
• fluorescenční protilátková technika MeSH
• fosforylace MeSH
• glioblastom etiologie   metabolismus   patologie   MeSH
• imunohistochemie MeSH
• kultivované buňky MeSH
• lidé MeSH
• membránové proteiny genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádorové mikroprostředí účinky léků   genetika   MeSH
• regulace genové exprese u nádorů * účinky léků   MeSH
• transformující růstový faktor beta1 metabolismus   farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• endopeptidasy MeSH
• fibroblast activation protein alpha MeSH Prohlížeč
• membránové proteiny MeSH
• TGFB1 protein, human MeSH Prohlížeč
• transformující růstový faktor beta1 MeSH

Interleukin-6 (IL-6) is a cytokine with multifaceted effects playing a remarkable role in the initiation of the immune response. The increased level of this cytokine in the elderly seems to be associated with the chronic inflammatory setting of the microenvironment in aged individuals. IL-6 also represents one of the main signals in communication between cancer cells and their non-malignant neighbours within the tumour niche. IL-6 also participates in the development of a premetastatic niche and in the adjustment of the metabolism in terminal-stage patients suffering from a malignant disease. IL-6 is a fundamental factor of the cytokine storm in patients with severe COVID-19, where it is responsible for the fatal outcome of the disease. A better understanding of the role of IL-6 under physiological as well as pathological conditions and the preparation of new strategies for the therapeutic control of the IL-6 axis may help to manage the problems associated with the elderly, cancer, and serious viral infections.

• Klíčová slova
• COVID-19, IL-6, ageing, cancer ecosystem, cancer-associated fibroblasts, cytokine, cytokine storm, tumour microenvironment,
• MeSH
• COVID-19 MeSH
• interleukin-6 genetika   metabolismus   MeSH
• koronavirové infekce metabolismus   patologie   MeSH
• lidé MeSH
• nádory metabolismus   patologie   MeSH
• pandemie MeSH
• signální transdukce MeSH
• stárnutí metabolismus   patologie   MeSH
• virová pneumonie metabolismus   patologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• interleukin-6 MeSH