Publications by authors named "Galina A Posypanova"

Purpose: In recent years, a growing number of studies have focused on the mechanisms of action of densely ionizing radiation. This is associated with the development of radiation therapy of tumors using accelerated ions. The use of densely ionizing radiation appears to be the most promising method, optimal for treating patients with severe radioresistant forms, such as widespread head and neck tumors, recurrent and metastatic tumors, and some forms of brain tumors.

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Somatostatin analogues play an important role in the therapy of neuroendocrine tumors by binding to somatostatin receptors on the surface of cancer cells. In this work, we analyze the receptor-binding affinity and in vitro stability of a novel ultra-short somatostatin analogue Thz-Phe-D-Trp-Lys-Thr-DOTA (DOTA-P4). This conjugate is successfully radiolabeled with Sc, Y, Eu, and Bi, characterized and validated by thin layer and high-performance liquid chromatography.

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The alpha-fetoprotein (AFP) binding protein, a putative AFP receptor, is a tumour marker that is present on the surfaces of malignant cells. AFP enters cells through receptor-mediated endocytosis. The recombinant C-terminal fragment of AFP (AFP-3BC, which consists of amino acid residues 473-596) was obtained by the expression in Escherichia coli.

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Human alpha-fetoprotein (hAFP) is an oncofetal protein which is a common cancer marker. Conjugates of native hAFP with different cytostatic agents inhibit growth of cancer cells in vivo and in vitro. The hAFP interacts with its receptor (AFPR) on the surface of cancer cells via its C-terminal domain.

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Bacterial L-asparaginases are enzymes that catalyze the hydrolysis of l-asparagine to aspartic acid. For the past 30 years, these enzymes have been used as therapeutic agents in the treatment of acute childhood lymphoblastic leukemia. Their intrinsic low-rate glutaminase activity, however, causes serious side-effects, including neurotoxicity, hepatitis, coagulopathy, and other dysfunctions.

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The specific receptor of alpha-fetoprotein (AFP) is a universal tumor marker, being expressed on the surface of many tumor cells, but not in normal human tissues. AFP enters the cell by receptor-mediated endocytosis; its receptor-binding site is hypothetically localized in the third domain of AFP. A recombinant C-terminal AFP fragment, which contains all the third and a part of the second domains of hAFP, was produced.

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The object of this work was to study (i) the effect of monoclonal antibodies (mAb) to a receptor (R) of an oncofetal protein of an alpha-fetoprotein (AFP) on the survival rate and sensitivity of tumor target cells to the cytotoxic action of effector cells, (ii) the level of Ab to AFP-R in the blood serum of patients with malignant tumors (iii) the effect of blood serum with a high level of Ab to AFP-R on the survival rate of tumor cells in vitro, and also (iv) the effect of immunization of animals with an AFP-R preparation on subsequent development of a grafted tumor. It is shown that mAb to AFP-R of clones 2E1, 5C6 and 2B8 effectively bond to both mouse tumor cells and to human tumor cells. Monoclonal Ab to AFP-R of the studied clones do not affect the proliferation of tumor cells of mice and insignificantly inhibit the proliferation of human tumor cells.

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