A Nonpeptidic Cathepsin S Activity-Based Probe for Noninvasive Optical Imaging of Tumor-Associated Macrophages

Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Chemistry & biology (Impact Factor: 6.59). 05/2012; 19(5):619-28. DOI: 10.1016/j.chembiol.2012.03.012
Source: PubMed

ABSTRACT Macrophage infiltration into tumors has been correlated with poor clinical outcome in multiple cancer types. Therefore, tools to image tumor-associated macrophages could be valuable for diagnosis and prognosis of cancer. Herein, we describe the synthesis and characterization of a cathepsin S-directed, quenched activity-based probe (qABP), BMV083. This probe makes use of an optimized nonpeptidic scaffold leading to enhanced in vivo properties relative to previously reported peptide-based probes. In a syngeneic breast cancer model, BMV083 provides high tumor-specific fluorescence that can be visualized using noninvasive optical imaging methods. Furthermore, analysis of probe-labeled cells demonstrates that the probe primarily targets macrophages with an M2 phenotype. Thus, BMV083 is a potential valuable in vivo reporter for tumor-associated macrophages that could greatly facilitate the future studies of macrophage function in the process of tumorigenesis.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Proteolytic enzymes are key signaling molecules in both normal physiological processes and various diseases. After synthesis, protease activity is tightly controlled. Consequently, levels of protease messenger RNA and protein often are not good indicators of total protease activity. To more accurately assign function to new proteases, investigators require methods that can be used to detect and quantify proteolysis. In this review, we describe basic principles, recent advances, and applications of biochemical methods to track protease activity, with an emphasis on the use of activity-based probes (ABPs) to detect protease activity. We describe ABP design principles and use case studies to illustrate the application of ABPs to protease enzymology, discovery and development of protease-targeted drugs, and detection and validation of proteases as biomarkers.
    Annual Review of Biochemistry 06/2014; 83:249-273. DOI:10.1146/annurev-biochem-060713-035352 · 26.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Die Synthese und Anwendung zweier für Cathepsin S spezifischer Sonden wird beschrieben. Um den langfristigen Verbleib der Sonden am Zielort und eine hohes Signal/Rausch-Verhältnis zu erzielen, wurde ein Lipidierungsansatz über das Einfügen eines Palmitinsäurerestes eingesetzt. Nach Cathepsin-S-induzierter Spaltung in Zellen und im transplantierten Tumormausmodell stieg die Fluoreszenz durch Entlöschen stark an, und wir beobachteten eine intrazelluläre Anreicherung der Fluoreszenz im Tumorgewebe. Im Vergleich zur nichtlipidierten Sonde lieferte die lipidierte Sonde ein anhaltendes starkes Fluoreszenzsignal im Tumor. Dies zeigt, dass nichtinvasive Tumoridentifikation per Fluoreszenz möglich ist. Das Prinzip der Lipidierungs-vermittelten Verabreichung kann potenziell auch auf zytotoxische Verbindungen erweitert werden, um Tumormasse zu reduzieren.
    Angewandte Chemie 07/2014; 126(29). DOI:10.1002/ange.201310979
  • [Show abstract] [Hide abstract]
    ABSTRACT: Activity-based protein profiling (ABPP) is the field of research that aims to obtain information on the activity of a protein or protein family within the context of a biological system. In order to enable the monitoring of enzymatic activity, ABPP strategies make use of active-site directed chemical probes, termed activity-based probes (ABPs). These probes bind in a mechanism-based and irreversible manner to a specific target enzyme or multiple members of an enzyme family. Over the past decades, many different ABPs have been described that target a wide variety of enzyme classes, ranging from the more classical ABPs targeting cysteine proteases to very recently developed ABPs for oxidases. Recent advancements in ABPP have led to the selective imaging of enzymatic activity in vivo and the use of ABPP for drug discovery applications. In this review we provide an overview of the design principles that underlie ABP development. We discuss the various factors that should be considered when designing a new probe, including the reactivity of active site residues towards particular chemical groups, the desired specificity of the probe for either a single enzyme or a larger enzyme class, and the intended use of the ABP, for instance in vivo imaging. Furthermore, we describe some of the most recent developments in ABPP that have made major contributions to the advancement of the field.
    Bioconjugate Chemistry 06/2014; 25(7). DOI:10.1021/bc500208y · 4.82 Impact Factor

Full-text (2 Sources)

Available from
Jun 1, 2014