Remodulating effect of doxorubicin on the state of iron-containing proteins, and redox characteristics of tumor with allowance for its sensitivity to cytostatic agents.

The study was aimed at determining the changes of metal-containing proteins in blood serum and tumor tissue of animals with parental and doxorubicin-resistant strains of Walker-256 carcinosarcoma before and after the cytostatic administration. It has been shown that upon doxorubicin action the levels of total iron and transferrin in the tissues from the both groups of animals decreased while that of ferritine simultaneously increased with more pronounced pattern in the group of animals with resistant tumor strain. It has been shown that upon the action of doxorubicin in tumor tissue of animals with different sensitivity to the cytostatic there could be observed oppositely directed changes in the redox state of these cells that in turn determined the content of “ free iron” complexes, RO S generation and concentration of active forms of matrix metaloproteinase- 2 and matrix metaloproteinase-9, namely, the increase of these indexes in animals with parental strain and their decrease in animals with the resistant one.

[Lewis lung carcinoma variant with high sensitivity to antitumor antiangiogenic therapy reveals a high capacity to autophagy].

Comparative investigation of two variants of Lewis lung carcinoma cells (LLC and LLC/R9) growing under nutrient deficiency caused by long-term incubation without growth medium replacement was performed. It was established that LLC/R9 cells which in contrast to LLC cells had a high sensitivity to antitumor antiangiogenic therapy (AAT) revealed a high dependence of their survival from glucose level in growth medium as well as high capacity to autophagy under nutrient deficiency. Perhaps high autophagy activity in tumor cells may be considered as a marker of tumor AAT sensitivity.

Ultrastructural and some functional changes in tumor cells treated with stabilized iron oxide nanoparticles.

Aim: To study the ultrastructure and some functional indexes of tumor cells treated with stabilized iron nanoparticles in vitro.

Methods: 3-[4,5dimethylthiazol-2-1]-2,5-diphenyltetrazolium bromide (MTT)-test, electron microscopy, polarography with applying of closed Clark's electrode.

Results: It was shown that cultivation of cells with stabilized Fe(3)O(4) leads to intracellular accumulation of ferromagnetic nanoparticles.

Molecular profile and cell cycle in MCF-7 cells resistant to cisplatin and doxorubicin.

Aim: To compare ultrastructure, phenotypic profile and cell cycle progression of MCF-7 human breast cancer cells and MCF7 sublines resistant to cisplatin (MCF-7/DDP) and doxorubicin (MCF-7/DOX).

Methods: MTT-test, immunocytochemistry, flow cytometry, electron microscopy.

Results: The development of drug resistance to cisplatin and doxorubicin in MCF-7 cells upon the culturing of the initial cells with the raising concentrations of cytostatics was accompanied by the increase in cells adhesion, the increasing differentiation grade and the loss of steroid hormone receptors.

Modifying influence of prolonged action of interferon on phenotypic characteristics of human lung cancer cells in vitro.

Aim: To study modifying influence of interferon (IFN) on some phenotypic properties of human non-small-cell lung cancer cells (NSCLC) upon prolonged exposition of the cells with IFN.

Materials And Methods: A-549 cells were cultivated with IFN at increasing concentrations for a long period of time (up to 1 year). Cell morphology and ultrastructure were studied by light and electron microscopy.

[Ultrastructural organization of carcinoma Lewis (3LL) cells during cisplatin resistance formation].

The electron-microscopic analysis of the morphological status of 3LL (Lewis) carcinoma tumour cells in the process of cisplatin resistant phenotype formation has been performed. It was shown that selection of tumour cells forming cell clones characterized by more complicated nuclear and cytoplasm organization took place. The tumour cells had the diffused nuclear chromatin; nuclear envelope had the numerous pores with expanded diaphragms.

Role of DNA hypomethylation in the development of the resistance to doxorubicin in human MCF-7 breast adenocarcinoma cells.

The resistance of cancer cells to chemotherapeutic agents is a major clinical problem and an important cause of treatment failure in cancer. Mechanisms that have developed to guard cancer cells against anti-cancer drugs are major barriers to successful anti-cancer therapy. Therefore, the identification of novel mechanisms of cellular resistance holds the promise of leading to better treatments for cancer patients.

Role of polyamines in the function of nuclear transcription factor NF-kappaB in breast cancer cells.

Unlabelled: The aim of the work was the investigation of the influence of polyamines on formation of nuclear transcription factor kappa B (NF-kappaB) complex with specific DNA-sequences nuclear response elements (NRE), and the study of content of p50 and p65 (NF-kappaB subunits) in breast tumor cells under polyamines metabolism modulation.

Methods: The model experiments in vitro were carried out on cultured MCF-7 cells, in vivo experiments -- on experimental Ca755 and Walker-256 tumors using surface plasmon resonance (SPR) and Western-blotting analysis.

Results: The data have demonstrated that polyamines falicitated p50 -- NRE binding.

[A method for the chemical treatment of cells for the purpose of the subsequent study of the same cell culture preparation by light, scanning and transmission electron microscopy].

Cells cultured on transparent conductive substrates (glass coated with indium oxide) were fixed with aldehyde and osmium tetroxide and then treated with tannic acid, uranyl acetate and lead citrate. The same cell culture preparation could be sequentially studied by light microscopy (in water immersed condition), SEM (after dehydration and critical point drying) and TEM (after embedding in an epoxy resin). This method ensures the preservation of intact cell morphology, cell surface topography and intracellular structures.

[Ultrastructural anomalies of the desmosomal contacts in monolayer transformed cultures].

The ultrastructure of cell-cell desmosomal contacts and their cytoskeletal components in the cellular monolayer of transformed epithelial cultures is studied. It is suggested that asymmetry of the desmosomal contact formation, the formation of hemidesmosome-like structures on the lateral surface of one of the contacted cells and defects of cytoskeletal desmosomal components are related to transformational changes in the functionally different contacted cells.

[Ultrastructure of L-line lipoblast-like cells during cloning in a medium with a high serum concentration].

The ultrastructure of lipoblast-like cells produced by clones of transformed culture of strain in the medium with an increased (60%) concentration of bovine serum was studied. The aim of using the stimulator rich in adipogenous factors was the elucidation of the origin of lipid accumulation in some of cell types during heterogeneous differentiation of clones. In these conditions non-differentiated lipoblasts assumed the fine structure of mature lipid cells.

[Cellular ultrastructure of a cloned L-line culture].

A study of the fine structure of cells obtained from the transformed cloned culture of strain L, that have developed from a single cell, demonstrated several different cell types. The clones contained both non-differentiated and poorly-differentiated cells. The presence of morphotypical signs in the poorly-differentiated cells allowed to reveal some cell clone types and the direction of their specialization process.

[L line cell differentiation. Histochemical and electron microscopic studies].

In a medium supplemented with 60 per cent large cattle serum, part of the cell population of L-transformed culture was seen to be differentiated into mature lipocytes. The formation of structures similar to normal fat tissue took place in the same conditions, provided a reduced quantity of the seeded cells was used. The cell differentiation was accompanied with a decrease in acid phosphatase and non-specific esterase activities.

[Effect of chemical carcinogens on the ultrastructure of cultured differentiating myogenic cells].

The electron microscope studies have been carried out on primary monolayer tissue culture obtained from body tissues of rat and C3H mouse embryos. The cells of tissue culture were mainly myoblasts and fibroblast-like cells. The cultures were treated with two different carcinogenic substances--benz(a)-pyrene (BP) and methylnitrosonitroguanidine (MNNG).