Oncogerminative hypothesis of tumor formation.

The oncogerminative hypothesis of tumor formation states that during malignant transformation of somatic cells part of the germinative cell genome is activated. This part determines the phenotype property of the germinative cell: its potential immortality realized during its life cycle. In malignant cells this activated part of the genome also determines immortality in its life cycle.

Monoclonal antibodies of IPO series against B cell differentiation antigens in leukemia and lymphoma immunophenotyping.

Monoclonal antibodies (mAbs) of IPO series were developed following immunization with human B cell lines RPMI-1788, Daudi, and spleen cells from a patient with hairy cell leukemia. Reactivity of these mAbs was studied on 19 human cell lines, mononuclear cells of 50 healthy persons and 142 patients with leukemias and lymphomas. It was shown that mAbs IPO-3, IPO-10 and IPO-24 define B cell-specific antigens expressed at different stages of maturation.

Immunocytochemical staining of cells in 153 pleural effusions with a panel of monoclonal antibodies and lectins.

A panel of markers, including MAbs to different epitopes of CEA, B 6.2, detection of AP activity and lectin receptors (PNA, HPL, SBA, LAL, LcL) for cell identification in pleural effusions, is proposed. Using immunocytochemical methods cancer cells were determined in all 80 cytological positive and in 13 from 21 cytologically negative cancer effusions.

Intracellular ratio between monovalent cations (Na+/K+), and transcriptional activity of genes in tumour cells.

The effects of the intracellular Na+/K+ ratio on transcriptional activity of ribosomal, c-fos, beta-actin and histone genes of Ehrlich ascites tumour cells and P-388 leukaemia cells have been investigated. Optimum values of the Na+/K+ ratio for selective transcription of genes are shown, they are in accordance with the Na+/K+ ratio and mRNA content of respective genes during the cell cycle. Differential activation and repression of these genes do not correlate with the total synthesis rate of RNA during the cell cycle.

The carcinogenic danger of nitrie pollution of the environment.

Presented are the literature data as well as the results of our own investigations on the genotoxic and carcinogenic effects of sodium nitrite (SN). The carcinogenicity of SN detected in animal experiments appears to be related to the formation of nitroso compounds from endogenous nitrosable precursors. Sodium nitrite possesses transforming and promoting effects in cell cultures, as well as mutagenic effects in the bacterial systems, where the predominant effect of SN was compared to that of N-nitrosodimethylamine (NDMA).

New approaches to ecological oncology.

A definition of ecological oncology is given and its subject is discussed. Primary attention is paid to insufficiently studied aspects of this novel scientific discipline: the influence of carcinogens on the natural biocenoses and their role in the evolutional processes, the transformation of carcinogens by living organisms, and the ecological monitoring of environmental carcinogenic substances.

DNA linking potential generated by gyrase.

Whether or not DNA gyrase can supercoil DNA so that alternative structures will arise in it is the major question of this work. We have shown gyrase to produce in pAO3 DNA a superhelix density sufficient for cruciform formation. However, the transition does not take place because of too slow kinetics.

Morphometric patterns and functional activity of the ascites tumour cells at different cell cycle stages.

Comparison of the morphometric patterns obtained by electron microscopy with data from the biochemical analysis of metabolism in Ehrlich ascites tumour cells and P-388 leukemia cells, in each phase of the cell cycle, shows a distinct correlation between structure and function which is demonstrated by the fact that stage duration in the structure changes coincides with metabolism alteration. Cell volume and total protein content increase simultaneously in all cell cycle stages. Decrease in the heterochromatin fraction in the nuclei occurs against the sharp DNA reduplication and transcription background.

Chemiluminescence of irradiated animal blood plasma.

Spontaneous and induced chemiluminescence of rat blood plasma following irradiation of the animals with fast neurons was studied. Dynamics of the luminescence reflected the degree of radiation injury and an oscillatory response of blood chemiluminescent effect was observed.

Induced hyperglycemia and tumor chemotherapy: experimental and clinical studies.

In order to clarify the influence of induced hyperglycemia upon antitumor effects of chemotherapy we studied some animal and human tumors. We observed that hyperglycemia enhances the antitumor effects of some cytostatic drugs several fold, due in part to the changes in the microphysiology induced by the hyperglycemia. Time doubling of some transplanted rat tumors and survival time of rats, rabbits and dogs bearing the transplanted and spontaneous tumors increased two to ten fold when the chemotherapy was used under hyperglycemia.

Energy supply of the mitotic cell cycle and the Na+/H+-antiport in ascites tumors.

The activation of Na+ transport is due to the exchange of protons formed via glucose conversion into lactate for Na+, i.e., to the stimulation of the Na+/H+-antiport.

Cationic control of gene transcription in tumour cells.

Using ascites tumour cells (Ehrlich carcinoma, plasmacytoma MOPS-21, leukaemia P-388, lympholeukaemia NK/Ly) and bone marrow cells from normal rats, we have demonstrated that transcription of a gene coding for the 35S RNA can be regulated via alteration of the Na+/K+ ratio in the cells. The 35S RNA was transcriptionally active within the range 1 less than or equal to Na+/K+ less than 3 but was switched off at Na+/K+ less than 1. In synchronized Ehrlich carcinoma cells this gene was activated in the early phases of the cell cycle, when the Na+/K+ ratio in the cells exceeded 1.

Monoclonal antibodies IPO-3 and IPO-10 against human B cell differentiation antigens.

Monoclonal antibodies (mAbs) IPO-3 and IPO-10 were generated following immunization of a BALB/c mice with human cell lines RPMI-1788 and Daudi respectively. The reactivity of these mAbs was studied by indirect immunofluorescence technique with 10 human cell lines, blood cells of healthy persons and patients with the malignant lymphoproliferative diseases. Studies of normal and neoplastic B cells suggest that mAbs IPO-3 and IPO-10 which recognize antigens are B lineage restricted.

Differential expression of cellular genes in Rauscher leukaemia.

The methods of hybridization in solution and blot hybridization showed that spleen cells from BALB/c mice contain "silent" genes which can amplify and change their structure after infection by Rauscher leukaemia virus. The "silent" gene product is nuclear 35S RNA detectable by comparative electrophoretic analysis of the heterogeneous nuclear RNA from leukaemic and normal cells. About 7% of this 35S RNA is represented by the virus-specific sequences, but a major part is represented by the cellular sequences.