{"entity": "researcher", "timestamp": "2026-08-22T08:30:29.222Z", "family": "Bezverkhniaia", "given": "Ekaterina", "initials": "E", "orcid": "0000-0001-7699-5719", "affiliations": ["Department of Medicinal Chemistry, Uppsala University, 751 23 Uppsala, Sweden.", "Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634009 Tomsk, Russia.", "Scientific and Research Laboratory of Chemical and Pharmaceutical Research, Siberian State Medical University, 634050 Tomsk, Russia."], "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/researcher/211d24252bc84d43aed1d7ed4c3d3238.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/researcher/211d24252bc84d43aed1d7ed4c3d3238"}}, "publications": [{"entity": "publication", "iuid": "686e6e55613a4b12ace642daaf877885", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/686e6e55613a4b12ace642daaf877885.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/686e6e55613a4b12ace642daaf877885"}}, "title": "Influence of Molecular Design on the Tumor Targeting and Biodistribution of PSMA-Binding Tracers Labeled with Technetium-99m.", "authors": [{"family": "Bezverkhniaia", "given": "Ekaterina", "initials": "E", "orcid": "0000-0001-7699-5719", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/211d24252bc84d43aed1d7ed4c3d3238.json"}}, {"family": "Kanellopoulos", "given": "Panagiotis", "initials": "P", "orcid": "0000-0002-0617-3936", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/85ce3df2ffae4754946f11bb2e98ef97.json"}}, {"family": "Rosenstr\u00f6m", "given": "Ulrika", "initials": "U", "orcid": "0000-0002-0817-8140", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/ec6820fcb786475d85969630b0b3860b.json"}}, {"family": "Tolmachev", "given": "Vladimir", "initials": "V", "orcid": "0000-0002-6122-1734", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/896ae9fae8b74251afe11b4354c62794.json"}}, {"family": "Orlova", "given": "Anna", "initials": "A", "orcid": "0000-0001-6120-2683", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/1c374f429702489494c05f84f298b4b7.json"}}], "type": "journal article", "published": "2024-03-23", "journal": {"title": "Int J Mol Sci", "issn": "1422-0067", "volume": "25", "issue": "7", "issn-l": null}, "abstract": "Previously, we designed the EuK-based PSMA ligand BQ0413 with an maE3 chelator for labeling with technetium-99m. It showed efficient tumor targeting, but our preclinical data and preliminary clinical results indicated that the renal excretion levels need to be decreased. We hypothesized that this could be achieved by a decrease in the ligand's total negative charge, achieved by substituting negatively charged glutamate residues in the chelator with glycine. The purpose of this study was to evaluate the tumor targeting and biodistribution of two new PSMA inhibitors, BQ0411 and BQ0412, compared to BQ0413. Conjugates were radiolabeled with Tc-99m and characterized in vitro, using PC3-pip cells, and in vivo, using NMRI and PC3-pip tumor-bearing mice. [99mTc]Tc-BQ0411 and [99mTc]Tc-BQ0412 demonstrated PSMA-specific binding to PC3-pip cells with picomolar affinity. The biodistribution pattern for the new conjugates was characterized by rapid excretion. The tumor uptake for [99mTc]Tc-BQ0411 was 1.6-fold higher compared to [99mTc]Tc-BQ0412 and [99mTc]Tc-BQ0413. [99mTc]Tc-BQ0413 has demonstrated predominantly renal excretion, while the new conjugates underwent both renal and hepatobiliary excretion. In this study, we have demonstrated that in such small targeting ligands as PSMA-binding EuK-based pseudopeptides, the structural blocks that do not participate in binding could have a crucial role in tumor targeting and biodistribution. The presence of a glycine-based coupling linker in BQ0411 and BQ0413 seems to optimize biodistribution. In conclusion, the substitution of amino acids in the chelating sequence is a promising method to alter the biodistribution of [99mTc]Tc-labeled small-molecule PSMA inhibitors. Further improvement of the biodistribution properties of BQ0413 is needed.", "doi": "10.3390/ijms25073615", "pmid": "38612427", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC11011439"}, {"db": "pii", "key": "ijms25073615"}], "notes": [], "created": "2026-08-21T13:03:53.276Z", "modified": "2026-08-21T13:03:53.348Z"}, {"entity": "publication", "iuid": "8dd62b52564244adb5b31b41d3dad8c8", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/8dd62b52564244adb5b31b41d3dad8c8.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/8dd62b52564244adb5b31b41d3dad8c8"}}, "title": "Preclinical Evaluation of a Novel High-Affinity Radioligand [99mTc]Tc-BQ0413 Targeting Prostate-Specific Membrane Antigen (PSMA).", "authors": [{"family": "Bezverkhniaia", "given": "Ekaterina", "initials": "E", "orcid": "0000-0001-7699-5719", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/211d24252bc84d43aed1d7ed4c3d3238.json"}}, {"family": "Kanellopoulos", "given": "Panagiotis", "initials": "P", "orcid": "0000-0002-0617-3936", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/85ce3df2ffae4754946f11bb2e98ef97.json"}}, {"family": "Abouzayed", "given": "Ayman", "initials": "A"}, {"family": "Larkina", "given": "Mariia", "initials": "M", "orcid": "0000-0003-1176-2441", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/557c8a9c8b2142a7a88d6211335d24e4.json"}}, {"family": "Oroujeni", "given": "Maryam", "initials": "M", "orcid": "0000-0003-2660-9837", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/8bdd7a76401c42b4bbe8b11cfdb83212.json"}}, {"family": "Vorobyeva", "given": "Anzhelika", "initials": "A", "orcid": "0000-0002-4778-3909", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/99703faa11ab4c19aff2f426f61c3134.json"}}, {"family": "Rosenstr\u00f6m", "given": "Ulrika", "initials": "U", "orcid": "0000-0002-0817-8140", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/ec6820fcb786475d85969630b0b3860b.json"}}, {"family": "Tolmachev", "given": "Vladimir", "initials": "V", "orcid": "0000-0002-6122-1734", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/896ae9fae8b74251afe11b4354c62794.json"}}, {"family": "Orlova", "given": "Anna", "initials": "A", "orcid": "0000-0001-6120-2683", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/1c374f429702489494c05f84f298b4b7.json"}}], "type": "journal article", "published": "2023-12-12", "journal": {"title": "Int J Mol Sci", "issn": "1422-0067", "volume": "24", "issue": "24", "issn-l": null}, "abstract": "Radionuclide imaging using radiolabeled inhibitors of prostate-specific membrane antigen (PSMA) can be used for the staging of prostate cancer. Previously, we optimized the Glu-urea-Lys binding moiety using a linker structure containing 2-napththyl-L-alanine and L-tyrosine. We have now designed a molecule that contains mercaptoacetyl-triglutamate chelator for labeling with Tc-99m (designated as BQ0413). The purpose of this study was to evaluate the imaging properties of [99mTc]Tc-BQ0413. PSMA-transfected PC3-pip cells were used to evaluate the specificity and affinity of [99mTc]Tc-BQ0413 binding in vitro. PC3-pip tumor-bearing BALB/C nu/nu mice were used as an in vivo model. [99mTc]Tc-BQ0413 bound specifically to PC3-pip cells with an affinity of 33 \u00b1 15 pM. In tumor-bearing mice, the tumor uptake of [99mTc]Tc-BQ0413 (38 \u00b1 6 %IA/g in PC3-pip 3 h after the injection of 40 pmol) was dependent on PSMA expression (3 \u00b1 2 %IA/g and 0.9 \u00b1 0.3 %IA/g in PSMA-negative PC-3 and SKOV-3 tumors, respectively). We show that both unlabeled BQ0413 and the commonly used binder PSMA-11 enable the blocking of [99mTc]Tc-BQ0413 uptake in normal PSMA-expressing tissues without blocking the uptake in tumors. This resulted in an appreciable increase in tumor-to-organ ratios. At the same injected mass (5 nmol), the use of BQ0413 was more efficient in suppressing renal uptake than the use of PSMA-11. In conclusion, [99mTc]Tc-BQ0413 is a promising probe for the visualization of PSMA-positive lesions using single-photon emission computed tomography (SPECT).", "doi": "10.3390/ijms242417391", "pmid": "38139219", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC10743726"}, {"db": "pii", "key": "ijms242417391"}], "notes": [], "created": "2026-08-21T13:03:48.635Z", "modified": "2026-08-21T13:03:48.835Z"}, {"entity": "publication", "iuid": "ab67eb7a966e4796b3cb5750aa00c79b", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/ab67eb7a966e4796b3cb5750aa00c79b.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/ab67eb7a966e4796b3cb5750aa00c79b"}}, "title": "Radionuclide Molecular Imaging of EpCAM Expression in Triple-Negative Breast Cancer Using the Scaffold Protein DARPin Ec1.", "authors": [{"family": "Vorobyeva", "given": "Anzhelika", "initials": "A", "orcid": "0000-0002-4778-3909", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/99703faa11ab4c19aff2f426f61c3134.json"}}, {"family": "Bezverkhniaia", "given": "Ekaterina", "initials": "E", "orcid": "0000-0001-7699-5719", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/211d24252bc84d43aed1d7ed4c3d3238.json"}}, {"family": "Konovalova", "given": "Elena", "initials": "E"}, {"family": "Schulga", "given": "Alexey", "initials": "A", "orcid": "0000-0003-3425-0828", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/45b1c8e5447c41bbb93e61706377a0c7.json"}}, {"family": "Garousi", "given": "Javad", "initials": "J", "orcid": "0000-0002-7224-6304", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/e103143bca5f4a5791c496ed36351132.json"}}, {"family": "Vorontsova", "given": "Olga", "initials": "O"}, {"family": "Abouzayed", "given": "Ayman", "initials": "A"}, {"family": "Orlova", "given": "Anna", "initials": "A", "orcid": "0000-0001-6120-2683", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/1c374f429702489494c05f84f298b4b7.json"}}, {"family": "Deyev", "given": "Sergey", "initials": "S", "orcid": "0000-0002-3952-0631", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/fb88df2aaa8a46a5957370b9258e2834.json"}}, {"family": "Tolmachev", "given": "Vladimir", "initials": "V", "orcid": "0000-0002-6122-1734", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/896ae9fae8b74251afe11b4354c62794.json"}}], "type": "journal article", "published": "2020-10-14", "journal": {"title": "Molecules", "issn": "1420-3049", "volume": "25", "issue": "20", "issn-l": "1420-3049"}, "abstract": "Efficient treatment of disseminated triple-negative breast cancer (TNBC) remains an unmet clinical need. The epithelial cell adhesion molecule (EpCAM) is often overexpressed on the surface of TNBC cells, which makes EpCAM a potential therapeutic target. Radionuclide molecular imaging of EpCAM expression might permit selection of patients for EpCAM-targeting therapies. In this study, we evaluated a scaffold protein, designed ankyrin repeat protein (DARPin) Ec1, for imaging of EpCAM in TNBC. DARPin Ec1 was labeled with a non-residualizing [125I]I-para-iodobenzoate (PIB) label and a residualizing [99mTc]Tc(CO)3 label. Both imaging probes retained high binding specificity and affinity to EpCAM-expressing MDA-MB-468 TNBC cells after labeling. Internalization studies showed that Ec1 was retained on the surface of MDA-MB-468 cells to a high degree up to 24 h. Biodistribution in Balb/c nu/nu mice bearing MDA-MB-468 xenografts demonstrated specific uptake of both [125I]I-PIB-Ec1 and [99mTc]Tc(CO)3-Ec1 in TNBC tumors. [125I]I-PIB-Ec1 had appreciably lower uptake in normal organs compared with [99mTc]Tc(CO)3-Ec1, which resulted in significantly (p < 0.05) higher tumor-to-organ ratios. The biodistribution data were confirmed by micro-Single-Photon Emission Computed Tomography/Computed Tomography (microSPECT/CT) imaging. In conclusion, an indirectly radioiodinated Ec1 is the preferable probe for imaging of EpCAM in TNBC.", "doi": "10.3390/molecules25204719", "pmid": "33066684", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC7587533"}, {"db": "pii", "key": "molecules25204719"}], "notes": [], "created": "2026-08-21T13:04:24.418Z", "modified": "2026-08-21T13:04:24.508Z"}]}