Publications by authors named "Dyakova N"

The total mineral content was studied in medicinal plants from roadside and railside biotopes of the Voronezh region. Pharmacopoeial plant raw materials of 10 species were evaluated: roots of Taraxacum officinale F.H.

View Article and Find Full Text PDF

CRABP1 (cellular retinoic acid binding protein 1) belongs to the family of fatty acid binding proteins. Retinoic acid binding is the only known functional activity of this protein. The role of CRABP1 in human carcinogenesis remains poorly understood.

View Article and Find Full Text PDF

The hypothesis tested in the study suggests that mechanisms of the earlier described delayed or accelerated tumor progression may be regulated by the antiapoptotic and proapoptotic cellular programs activated in stress reactions of transformed cells to the host normal cellular environment. Therefore, spontaneously transformed hamster cell line STHE, its bcl-2-transduced line STHE-Bcl-2, and 64 of their descendant tumor cell variants naturally selected in two in vivo regimes (local tumor growth versus dissemination) were examined. The role of Bcl-2 and the possible activation of endogenous death-signaling Bax, Ras, and HSP90/HSP70 stress proteins in STHE (Bcl-2+/-) tumor cell variants were studied in dynamics of in vivo tumor progression.

View Article and Find Full Text PDF

Metastasis is the primary cause of mortality associated with cancer. Molecular mechanisms leading to metastatic spread are poorly studied. To get a better understanding of this process, we compared the gene expression pattern of two isogenic cell lines, HET-SR and HET-SR1 (Rous Sarcoma Virus-transformed embryo hamster fibroblasts) with different metastatic activity using the differential display technique.

View Article and Find Full Text PDF

RAS oncogenes play a critical role in oncogenic transformation and metastases formation. Here we show that Ha-ras greatly stimulates spontaneous metastatic activity of transformed cells through the Ras/RalGDS/RalA intracellular signaling pathway. Introduction of RalA alone leads to a drastic increase of metastatic activity of transformed cells.

View Article and Find Full Text PDF

Studies concerning the expression of the receptor CD95 (Fas) by tumor cells and the role of this protein in apoptosis induced by the effector host cells that bear Fas-ligand are mainly focused on the membrane-bound form of Fas. There are only a few data about the production of the soluble form of Fas by the tumor cells, its role in the interaction with the effector host cells, and the possible changes in the synthesis of this protein during tumor progression. In the present work, three in vitro transformed parental cell lines of different origin and 24 of their variants isolated after a short cycle of natural selection in vivo were studied.

View Article and Find Full Text PDF

As shown earlier, the cells transformed in vitro by various oncogenes, during subsequent in vivo growth were gradually replaced by descendant tumor cells, which co-expressed highly increased H(2)O(2)-catabolizing antioxidant activity (H(2)O(2)(CA)), and the ability to release PGE(2) (PGE(S)) in contact with natural killer cells; v-src was the only oncogene, which in vitro induced cells transformation characterised with the expression of [H(2)O(2)(CA)+PGE(S)] phenotype. Expression of [H(2)O(2)(CA)+PGE(S)] phenotype was providing tumor cells with significantly increased resistance to cytotoxic activities of macrophages and NK cells. However, the possible involvement of [H(2)O(2)(CA)+PGE(S)] phenotype in primary carcinogenesis remained obscure.

View Article and Find Full Text PDF

As shown earlier, the cells transformed in vitro by several different oncogenes, or spontaneously, during in vivo growth in normal hosts would be gradually replaced by the highly-tumorigenic descendants co-expressing high H2O2-catabolizing and PGE2-releasing activities. Acquisition of (H2O2(CA) + PGE(S)) phenotype provides the cells with local defense mechanisms against the host innate immunity effectors. However, it remained unknown, whether the expression of (H2O2(CA) + PGE(S)) phenotype is implicated in susceptibility of tumor cells expressing tumor-specific transplantation antigens to rejection in immune animals.

View Article and Find Full Text PDF

The ability of nonactivated peritoneal macrophages to induce nitric oxide (NO) secretion in transformed and tumor cells of the same origin differing in tumorigenic (TGA) and spontaneous metastatic activities (SMA) was examined. Low tumorigenic and nonmetastatic spontaneously transformed in vitro hamster embryo cells of the STHE strain in contact with macrophages, or their non-purified soluble product were the highest producers of NO. In vivo selected STHE cell variants characterized by middle or high TGA demonstrated low, or no NO production, respectively (independently of SMA- or SMA+).

View Article and Find Full Text PDF

We have earlier shown that Syrian hamster cells spontaneously transformed in vitro during in vivo progression, acquire in 1 step, along with highly increased tumorigenicity, 2 new properties characterizing the [H2O2CA + tPGE(S)] phenotype, i.e., a high H2O2 catabolizing (antioxidant) activity and the ability to release PGE2 upon contact with NK cells.

View Article and Find Full Text PDF

We have previously demonstrated that hamster embryo fibroblasts (HEFs) transformed by Rous Sarcoma virus, Schmidt-Ruppin strain (RSV-SR) are highly resistant to damage by H202 (H2O2R), (in contrast to HEFs transformed spontaneously, or by bovine adenovirus and SV40), while N-ras transfection of RSV-SR transformants leads to suppression of pp6Ov-scr and of H2O2R. In this study we have examined (1) mechanisms of antioxidant activity (AOA) of HEFs transformed by these agents and (2) the possible role of the v-src gene in unusually high AOA of RSV-SR transformants and of activated ras oncogenes in its suppression. All transformants exhibit increased catalase and glutathione peroxidase (GP) activities, while SOD, glutathione and glutathione reductase (GR) were reduced.

View Article and Find Full Text PDF

The main purposes of the study were: (1) in vivo comparison of accumulation of live tumorigenic cells (LTC) in macroscopically normal lungs of animals bearing 6 s.c. Syrian hamster sarcomas differing in spontaneous metastasizing activity (SMA); (2) in vitro examination of the sensitivity of these cell strains to the growth-regulating signals of normal fibroblasts.

View Article and Find Full Text PDF