Alexander V. Timoshenko

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Vascular endothelial growth factor C (VEGF-C) is a lymphangiogenic factor over-expressed in highly metastatic, cyclooxygenase (COX)-2 expressing breast cancer cells. We tested the hypothesis that tumour-derived VEGF-C may play an autocrine role in metastasis by promoting cellular motility through one or more VEGF-C-binding receptors VEGFR-2, VEGFR-3,(More)
Aberrant upregulation of COX-2 enzyme resulting in accumulation of PGE2 in a cancer cell environment is a marker for progression of many cancers, including breast cancer. Four subtypes of cell surface receptors (EP1, EP2, EP3, and EP4), which are coupled with different G-proteins, mediate PGE2 actions. Since migration is an essential step in invasion and(More)
Increased expression of COX-2 or VEGF-C has been correlated with progressive disease in certain cancers. Present study utilized several human breast cancer cell lines (MCF-7, T-47D, Hs578T and MDA-MB-231, varying in COX-2 expression) as well as 10 human breast cancer specimens to examine the roles of COX-2 and prostaglandin E (EP) receptors in VEGF-C(More)
CONTEXT The root cause of preeclampsia in the human lies in the placenta, where a subpopulation of cytotrophoblast cells called extravillous trophoblasts (EVT), known to be involved in the invasion of the uterine endometrium and utero-placental arteries, become less invasive, resulting in poor perfusion of maternal blood into placenta. OBJECTIVES Because(More)
Galectins, a family of soluble β-galactoside-binding proteins, serve as mediators of fundamental biological processes, such as cell growth, differentiation, adhesion, migration, survival, and death. The purpose of this review is to summarize the current knowledge regarding the ways in which the expression of individual galectins differs in normal and(More)
Superoxide production by neutrophils is believed to contribute to the efficiency of the host defence system. This activity is stimulated by the mannose-specific lectin concanavalin A, the N-acetylglucosamine/neuraminic acid-specific wheat germ agglutinin and the galactoside-specific lectins from Viscum album and human placenta. To assess whether this aspect(More)
To evaluate the significance of post-binding events for stable aggregate formation, the aggregation/dissociation of rat thymocytes initiated by two crosslinking plant lectins, namely concanavalin A (Con A) and Solanum tuberosum agglutinin (STA), were comparatively studied. Despite intimate cell contacts in the aggregates only Con A led to establishment of(More)
Initial ligand selection and the intermolecular spatial arrangement of glycan-lectin complexes are assumed to be essential to induce formation of stable cell aggregates by a lectin. To distinguish effects of these two processes, the tetrameric mistletoe lectin and its isolated B-chain were used. A reduced impact of multivalency for Ehrlich ascites tumor(More)
Bivalent lectins as bridging molecules between cells or cell surface lectins as docking points are involved in mediation of cell adhesion by specific recognition of suitable glycoconjugates on an opposing surface. The initial contact formation by a lectin can lead to intracellular post-binding events which effect stable cell association even in the presence(More)
Human platelets afford a suitable and physiologically relevant model to study receptor-dependent cell aggregation and ensuing biosignaling reactions. Since cell surface glycoconjugates can serve as ligands in recognitive protein--carbohydrate interactions, it is of interest to investigate the reactivity of such epitopes for a plant lectin and the elicited(More)