ABSTRACT
Prostate cancer is the second most common cancer among men. We designed and synthesized new ligands targeting prostate-specific membrane antigen and suitable for bimodal conjugates with diagnostic and therapeutic agents. In vitro studies of the affinity of the synthesized compounds to the protein target have been carried out. Based on these ligands, a series of bimodal conjugates with a combination of different mitosis inhibitors and antiandrogenic drugs were synthesized. The cytotoxicity of the compounds obtained in vitro was investigated on three different cell lines. The efficacy of the two obtained conjugates was evaluated in vivo in xenograft models of prostate cancer. These compounds have been shown to be highly effective in inhibiting the growth of PSMA-expressing tumors.
Subject(s)
Androgen Antagonists , Prostatic Neoplasms , Male , Humans , Androgen Antagonists/therapeutic use , Cytotoxins/therapeutic use , Prostate/pathology , Ligands , Cell Line, Tumor , Glutamate Carboxypeptidase II/metabolism , Antigens, Surface/metabolism , Prostatic Neoplasms/metabolismABSTRACT
We report an improved series of ligands targeting prostate specific membrane antigen (PSMA). The new compounds were designed by the introduction of changes in the structure of the aromatic fragment at ε-nitrogen atom of lysine that resulted in improved biological parameters. Some of them demonstrated high selectivity and nanomolar IC50 values. We synthesized and tested two conjugates with a fluorescent label Sulfo-Cy5 as an example of the use of the obtained PSMA inhibitors as a basis for the creation of diagnostic preparations.
Subject(s)
Lysine , Prostatic Neoplasms , Antigens, Surface , Cell Line, Tumor , Glutamate Carboxypeptidase II , Humans , Ligands , Male , NitrogenABSTRACT
Prostate cancer is one of the most commonly diagnosed men's cancers and remains one of the leading causes of cancer death. The development of approaches to the treatment of this oncological disease is an ongoing process. In this work, we have carried out the selection of ligands for the creation of conjugates based on the drug docetaxel and synthesized a series of three docetaxel conjugates. In vitro cytotoxicity of these molecules was evaluated using the MTT assay. Based on the assay results, we selected the conjugate which showed cytotoxic potential close to unmodified docetaxel. At the same time, the molar solubility of the resulting compound increased up to 20 times in comparison with the drug itself. In vivo evaluation on 22Rv1 (PSMA+) xenograft model demonstrated a good potency of the synthesized conjugate to inhibit tumor growth: the inhibition turned out to be more than 80% at a dose of 30 mg/kg. Pharmacokinetic parameters of conjugate distribution were analyzed. Also, it was found that PSMA-targeted docetaxel conjugate is less toxic than docetaxel itself, the decrease of molar acute toxicity in comparison with free docetaxel was up to 20%. Obtained conjugate PSMA-DOC is a good candidate for further expanded preclinical trials because of high antitumor activity, fewer side toxic effects and better solubility.
Subject(s)
Antineoplastic Agents/pharmacology , Docetaxel/pharmacology , Prostate-Specific Antigen/antagonists & inhibitors , Small Molecule Libraries/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Docetaxel/chemical synthesis , Docetaxel/chemistry , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Male , Mice , Mice, Inbred ICR , Molecular Structure , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Prostate-Specific Antigen/genetics , Prostate-Specific Antigen/metabolism , Rabbits , Rats , Rats, Wistar , Small Molecule Libraries/chemical synthesis , Small Molecule Libraries/chemistry , Structure-Activity RelationshipABSTRACT
Prostate cancer is the second most common type of cancer among men. Its main method of treatment is chemotherapy, which has a wide range of side effects. One of the solutions to this challenge is targeted delivery to prostate cancer cells. Here we synthesized a novel small-molecule PSMA-targeted conjugate based on the monomethyl auristatin E. Its structure and conformational properties were investigated by NMR spectroscopy. Cytotoxicity, intracellular reactive oxygen species induction, and stability under liver microsomes and P450-cytochrome species were investigated for this conjugate. The conjugate demonstrated 77-85% tumor growth inhibition levels on 22Rv1 (PSMA (+)) xenografts, compared with a 37% inhibition level on PC-3 (PSMA (-)) xenografts, in a single dose of 0.3 mg/kg and a sufficiently high therapeutic index of 21. Acute, chronic, and subchronic toxicities and pharmacokinetics have shown that the synthesized conjugate is a promising potential agent for the chemotherapy of prostate cancer.
Subject(s)
Antigens, Surface/chemistry , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Glutamate Carboxypeptidase II/chemistry , Oligopeptides/chemistry , Cell Line, Tumor , Coordination Complexes/chemical synthesis , Humans , Male , Microsomes, Liver/enzymology , Microsomes, Liver/metabolism , Prostatic Neoplasms/pathology , Reactive Oxygen Species/metabolism , Xenograft Model Antitumor AssaysABSTRACT
Prostate-specific membrane antigen (PSMA), also known as glutamate carboxypeptidase II (GCPII), is a suitable target for specific delivery of antitumor drugs and diagnostic agents due to its overexpression in prostate cancer cells. In the current work, we describe the design, synthesis, and biological evaluation of novel low-molecular PSMA ligands and conjugates with fluorescent dyes FAM-5, SulfoCy5, and SulfoCy7. In vitro evaluation of synthesized PSMA ligands on the activity of PSMA shows that the addition of aromatic amino acids into a linker structure leads to a significant increase in inhibition. The conjugates of the most potent ligand with FAM-5 as well as SulfoCy5 demonstrated high affinities to PSMA-expressing tumor cells in vitro. In vivo biodistribution in 22Rv1 xenografts in Balb/c nude mice of PSMA-SulfoCy5 and PSMA-SulfoCy7 conjugates with a novel PSMA ligand demonstrated good visualization of PSMA-expressing tumors. Also, the conjugate PSMA-SulfoCy7 demonstrated the absence of any explicit toxicity up to 87.9 mg/kg.
Subject(s)
Antigens, Surface/metabolism , Antineoplastic Agents/metabolism , Fluorescent Dyes/chemistry , Glutamate Carboxypeptidase II/metabolism , Ligands , Animals , Antigens, Surface/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Cell Survival/drug effects , Drug Screening Assays, Antitumor , Glutamate Carboxypeptidase II/chemistry , Humans , Male , Mice , Mice, Nude , Optical Imaging , Prostatic Neoplasms/drug therapy , Structure-Activity Relationship , Tissue Distribution , Transplantation, HeterologousABSTRACT
Prostate cancer (PC) is the second most commonly occurring cancer in men. Conventional chemotherapy has wide variety of disadvantages such as high systemic toxicity and low selectivity. Targeted drug delivery is a promising approach to decrease side effects of therapy. Prostate specific membrane antigen (PSMA) is overexpressed in prostate cancer cells while low level of expression is observed in normal cells. In this study we describe the development of Glu-urea-Lys based PSMA-targeting conjugates with paclitaxel. A series of new PSMA targeting conjugates with paclitaxel was designed and synthesized. The cytotoxicity of conjugates was evaluated against prostate (LNCaP, 22Rv1 and PC-3) and non-prostate (Hek293T, VA13, A549 and MCF-7) cell lines. The most promising conjugate 21 was examined in vivo using 22Rv1 xenograft mice model. It demonstrated good efficiency comparable with paclitaxel, while reduced toxicity. 3D molecular docking study was also performed to understand underlying mechanism of binding and further optimization of the linker substructure and conjugates structure for improving the target affinity. These conjugates may be useful for further design of novel PSMA targeting delivery systems for PC.
