Provided herein are compounds useful for imaging granzyme B. An exemplary compound provided herein is useful as a radiotracer for position emission tomography (PET) and/or single photon emission tomography (SPECT) imaging. Methods of imaging granzyme B, combination therapies, and kits comprising the granzyme B imaging agents are also provided.

Described herein are nanoprobes comprising ultrasmall aminated and cRGDY-conjugated nanoparticles labeled with Zirconium-89 (.sup.89Zr) and methods of their use. The provided compositions are renally clearable and possess suitable blood circulation half-time, high tumor active targeting capability, dominant renal clearance, low liver accumulation, and a high tumor-to-background ratio. The described nanoprobes exhibit great potential as “target-or-clear” tracers to human subjects for systemic targeted imaging (or treatment) of cancer.

Described herein are nanoprobes comprising ultrasmall aminated and cRGDY-conjugated nanoparticles labeled with Zirconium-89 (.sup.89Zr) and methods of their use. The provided compositions are renally clearable and possess suitable blood circulation half-time, high tumor active targeting capability, dominant renal clearance, low liver accumulation, and a high tumor-to-background ratio. The described nanoprobes exhibit great potential as “target-or-clear” tracers to human subjects for systemic targeted imaging (or treatment) of cancer.

Peptides that home, target, migrate to, are directed to, are retained by, or accumulate in and/or bind to the cartilage or kidney of a subject are disclosed. Pharmaceutical compositions and uses for peptides or peptide-active agent complexes comprising such peptides are also disclosed. Such compositions can be formulated for targeted delivery of an active agent to a target region, tissue, structure or cell in the cartilage. Targeted compositions of the disclosure can deliver peptide or peptide-active agent complexes to target regions, tissues, structures, or cells targeted by the peptide.

Peptides that home, target, migrate to, are directed to, are retained by, or accumulate in and/or bind to the cartilage or kidney of a subject are disclosed. Pharmaceutical compositions and uses for peptides or peptide-active agent complexes comprising such peptides are also disclosed. Such compositions can be formulated for targeted delivery of an active agent to a target region, tissue, structure or cell in the cartilage. Targeted compositions of the disclosure can deliver peptide or peptide-active agent complexes to target regions, tissues, structures, or cells targeted by the peptide.

Described is a labeling technique which can facilitate the metabolism in the liver after administration to patients without the reduction in the antibody function, thereby reducing accumulation of radionuclides in an organ such as the liver, and a modified antibody containing an IgG antibody and an IgG-binding peptide bound to the IgG antibody. The IgG-binding peptide has an amino acid sequence consisting of 13 to 17 amino acid residues, such as GPDCAYH(Xaa1)GELVWCTFH (SEQ ID NO: 2) wherein Xaa1 represents a lysine residue, a cysteine residue, an aspartic acid residue, a glutamic acid residue, 2-aminosuberic acid, or diaminopropionic acid, and a compound represented by the following formula (II-1) is linked at a position of the lysine residue via a modification linker to the N terminus of the IgG-binding peptide. ##STR00001##

A PSMA-specific agent comprising a compound according to Formula I or Formula II: wherein S.sub.1 is absent or is an organic spacer group comprising 3-10 carbons; A is an amino acid chain comprising 1 to 5 amino acids wherein at least one of the amino acids is selected from glutamic acid and aspartic acid; S2 is absent or is an organic spacer group comprising 1 to 15 carbons and/or 0 to 2 amino acids; I.sub.1 is an imaging group; and I.sub.2 is absent or is an imaging group. The PSMA-specific agents can be used to image PSMA within a tissue region and/or for the treatment of a cancer, such as prostate cancer.

##STR00001##

Methods and composition for cell-based therapy as well as somatostatin receptor-based therapy are described. For example, in certain aspects methods for administering an anti-tumor therapy using a signaling defective somatostatin receptor mutant are described. Furthermore, the invention provides compositions and methods involve a somatostatin constitutively active somatostatin receptor mutant.

The subject matter disclosed herein relates generally to cancer therapy and to anticancer compounds and imaging agents. More specifically, the subject matter disclosed herein relates to agents that target MC1R and their use in the treatment of cancer. Methods of screening for MC1R targeted agents are also disclosed.

The present invention provides a reporter system comprising (i) a gene expression construct for expression in a cell of a reporter gene, said reporter gene encoding a fusion protein comprising a transmembrane domain fused in-frame to a reporter domain, wherein said transmembrane domain upon insertion of the fusion protein into the cell membrane anchors the fusion protein in the cell membrane while expressing the reporter domain at the cell surface, and (ii) a reporter peptide labeled with a radiolabel, wherein said reporter domain comprises the large polypeptide subunit of a split luciferase, and wherein said reporter peptide comprises the small peptide subunit of said split luciferase, wherein both subunits associate by complementation to assemble into a luciferase complex.