Eksperimental'naia onkologiia最新文献

Cortiphen and cyclophosphamide were studied for their effect on the mixed uterus sarcoma induced primarily by 1,2-dimethylhydrazine and oestradiol-dipropionate in CBA mice and its transplants. Their inhibitory action on the growth of these tumours is established.

The antitumour activity of cortiphen synthesized at the All-Union Cancer Research Centre of the USSR Academy of Medical Sciences was studied on human tumour strains transplanted into nude mice and rats. Cortiphen was found to possess an expressed activity to kidney cancer, cancer of corpus uteri, chorionepithelioma, fibrosarcoma. Two strains of colon adenocarcinoma out of three have displayed an expressed sensitivity to cortiphen, while melanoma and Jewing sarcoma strains proved to be weakly sensitive to the preparation.

The antitumour efficacy of a single cryosurgery use in combination with hyperthermia was studied in 165 mice with the Lewis carcinoma, sarcoma 180 and 169 rats with Guérin's carcinoma and sarcoma 45. A considerable decrease in the recurrence frequency was observed irrespective of the histological type of the primary tumour. The haemostasis-associated expressed hypoxia has been established to arise in tumour tissues after cryodestruction. A day after the cryodestruction a shift to alkaline pH in the tumour tissue has been observed along with hypoxia. The above conditions possibly specify the high antitumour efficacy of a combined use of the cryosurgery and hyperthermia.

For the functional activity evaluation of glucocorticoid receptors (GR) a specific method for their activated form determination was developed on the experimental model of the rat liver. The method is based on the interaction of GR with DNA-cellulose. It has been shown that 26-41% of the total rat liver GR are able of undergoing activation and being bound to DNA-cellulose. Activated GR were studied in 88 renal tumours and in 37 melanomas. 20% of renal tumours and 33% of melanomas contain GR which are not able to undergo activation. The number of activated GR in most cases is much lower than the total GR number. There is no direct correlation between the concentrations of total and activated GR, as well as between the total GR content and the percent of activated forms in the whole receptor pool. It appears that the study of activated GR may give more reliable information about the hormone sensitivity of tumours than the determination of the total receptor content.

The intracellular Na+/K+ ratio was studied for its effect on histone genes expression in Ehrlich carcinoma and leukemia P-388 ascites cells. After equilibration with certain Na+/K+ ratio buffers at 0-4 degrees C the cells were treated during 1 h at 37 degrees C with ouabain added to the corresponding medium. Then total RNAs were extracted and analyzed by the reaction of blot-hybridization with histone genes cluster in plasmid p604. The maximal level of histone genes expression in leukemia P-388 cells was observed under conditions when intracellular Na+/K+ ratio corresponded to those at S-phase of the mitotic cycle. In Ehrlich carcinoma ascites cells the expression of histone genes was not dependent on the Na+/K+ ratio. A conclusion is drawn that the intracellular ratio of monovalent cations is one of the possible mechanisms which regulates the gene expression during the mitotic cycle.

It is established that application of the test-system "age-normal antibodies-leucocytes-lymphocytes" permits refusing in certain cases from the generally-accepted laboratory immunological tests and prognosticate their values depending on the test-system indices when using the regression models. The great incongruity of the predicted and real values of the concrete immunological index may be the manifestation of the risk factors associated with the oncological and other diseases.

Intracellular pH (pHi) of mouse lymphoid leukemia P388 cells was measured at the wavelength of 518 and 570 nm of fluorescein: pHi of rubomycin-sensitive P388 cells was higher than pHi of the cells resistant to this antitumour antibiotic (6.98 +/- 0.04 and 6.63 +/- 0.03, respectively, P less than 0.001). The role of pHi is established during induction of the resistance of tumour cells to the antitumour drugs.

The heterogeneity of cell populations with peanut agglutinin receptors in reactive tonsilar tissue has been stated. It contains B lymphocytes (HLA-DR+, CD 10+, IPO-10+ cells), part of T-cells (CD 4+), but no CD 8+ lymphocytes. PNA+ CD 10+ cells are the normal analogues of centrocytic non-Hodgkin's lymphomas.

The level of endogenous production of IL-2 by lymphocytes of lymph nodes regional to tumour and by mononuclear cells of peripheral blood, proliferative response of these cell to recombinant IL-2, as well as a modifying influence of autologous serum and actively proliferating bioptats of autologous tumours on enumerated parameters have been studied in cancer patients (tumours of the head and neck and locomotor system). Regional IL-2-dependent immunotherapy of malignant tumors with obligatory preliminary testing for individual sensitivity of the tumor bioptat to the influence of the RIL-2 and RIL-2 activated lymphocytes is shown to be promising.

The inhibition of polyamine synthesis by DFMO (2.7 x 10(-3) M) resulted in a decrease of proliferation rate of L and OH-1 cells. The patterns of acid-soluble nuclear proteins were studied by the SDS electrophoresis. The content of protein fraction with molecular weight 25 kD was shown to correlate with the rate of proliferation of cell cultures.