Immunohistochemical study of one of ascitic fluid antigens in patients with ovarian cancer using normal and tumor tissues

The indirect immunofluorescent technique has been used to study the localization and distribution of one of the ascitic fluid antigens (AgD) in patients with ovary carcinoma on sections of normal and tumour tissues. AgD was localized in the stromal fibres of connective tissue of several definitive and fetal kidneys as well as in more than half of cases in gastric, colonic, and ovary tumours (epithelial cancer) and in their metastases as well.     

Immunochemical study of antigens in the ascitic fluid of patients with ovarian cancer

5 antigens are identified in ascitic fluid from patients with ovarian tumours--AgA, AgB, AgV, AgG and AgD. Specific antisera are produced in rabbits by immunization with different protein and glycoprotein fractions of this fluid and by simultaneous injections of gamma-globulin fraction from antihuman plasma protein and pool of 25 ascitic fluids to rabbits. By the double immunodiffusion technique with standard test-systems for these antigens. It is found that all of them are absent in donor blood serum, but are present in certain normal and fetal tissues. AgA and AgD are also found in some extracts of lung, stomach, colon, and connective tissue tumours. The immunohistochemical and high-sensitive serological methods are necessary for determination of the usefulness of these antigens as tumour markers.     

Evaluation of the proliferative activity of malignant human tumors by an indirect immunofluorescent method using antithymidine antibodies

155 samples of human malignant tumours were studied by the immunofluorescent method and the antithymidine antibodies index-labelling (IL--% of tumour cells in the S-phase). Wide individual variability (0.1-73%) of IL of the studied tumours was shown to be present and to be preserved inside the tumours which were homogeneous by the histological type and developmental stage. A correlation between the labelling index and tumour differentiation in the gastric adenocarcinoma is observed.     

Characteristics of the epidermal growth factor receptors in the epithelium of the gastrointestinal tract of rats and in intestinal tumors induced by 1,2-dimethylhydrazine

Using the Scatchard analysis of 125J-EGF binding it was shown that plasma membranes of gastric and small intestinal epithelial cells contain approximately 20 times less EGF-receptors (EGF-R) than liver cells. Investigation of the phosphorylation activity of EGF-R-kinase was performed in vitro on plasma membranes from intestine, intestinal tumours and liver cells. The main protein phosphorylated at tyrosine in the tumours was p34 but the intensity of EGF-R autophosphorylation and its total protein-tyrosine kinase activity were reduced (as compared with small-intestinal and liver cell membranes). In the tumours of the colon induced by DMH an increased binding of 125J-EGF has been observed as compared with normal colonic enterocytes and increased number of EGF-R was clearly demonstrated. Phosphorylation of p34 in the intestinal membranes proceeds much more intensively than that of EGF-R.     

Organ-specific intestinal antigens contained in tumors of the human gastrointestinal tract

Two organospecific antigens were found in extracts of human fetal intestinal mucosa. One of them is destroyed by boiling and its electrophoretic mobility corresponds to that of beta 1-globulins. On the contrary, the other antigen is thermostable and its electrophoretic mobility corresponds to alpha 2 globulins. Other properties of these antigens are similar. The comparison of the test systems to these antigens in double immunodiffusion showed that they reacted with each other making a "spure", but these antigens immunologically differ from CEA. Both of organospecific antigens were determined in all extracts of nonmalignant specimens of definite intestinal and colon mucosa and in most extracts of colon tumours. These antigens are usually absent in extracts of other normal and tumour tissues. These antigens are suggested to be of use as tumour markers in immunodiagnosis, immunoclassification and immunolocalization of gastrointestinal cancer.     

The pharmacokinetics of the antitumor preparation of dimetinur

The pharmacological disposition of 1,3-dimethyl-1-nitrosourea (dimetinur) in intact rats and animals with Walker carcinosarcoma, glioma 2211, colon adenocarcinoma was studied by the colorimetric assay using an oral drug dose of 100 mg/kg. Computer analysis of data was based on a single-compartment model using the area under the concentration-time curve (S) and the intact drug half-life (t1/2) as main pharmacokinetic parameters. The highest level of the drug (S) was observed in tumour and brain tissues on an equality with drug distribution between blood, spleen, kidney and lungs. The half-life of the dimetinur removal from blood exceeds the known values for certain active NAM type. The antitumour activity of the drug against the studied tumours correlates positively with pharmacokinetic parameters for the tumours (S and 1/tmax).     

Determination of the individual sensitivity of human stomach cancer cells to fluoropyrimidines by the cytomorphological criteria of heterotransplants in diffusion chambers

An optimal morphologic complex of parameters for evaluation of individual sensitivity of heterotransplants to two anti-cancer drugs--5-fluorouracil and ftorafur has been developed on the basis of clinical and experimental material and using 76 gastric malignant tumours, 1320 heterotransplants in diffusion chambers (DC) in vivo which were implanted to 660 animal recipients. A simplified preclinical evaluation method of the individual sensitivity of the human gastric tumour to fluoropyrimidines is recommended based on dynamic level of mitotic activity in DC in vivo heterotransplants.     

Sensitivity of human tumor heterografts to a spin-labelled rubomycin derivative

A degree of emoksil activity has been determined by applying the subrenal capsule assay methodology to fresh surgical explants of the normal immunocompetent mice. The ability of emoksil to inhibit growth of breast and colon tumours xenografts was determined. Emoksil substitution for adriamycin in the combination therapy increases the therapeutic activity. The kinetic criterion kappa calculated by the method of equivalent exponents was suggested to determine the tumour susceptibility to the drugs.     

Specific growth rate and macrophagal infiltration of experimental tumors

The relationship between the macrophage infiltration and the specific growth rate of tumours was studied by the technique of spontaneous migration of lymphoreticular cells from tissue fragments. In the case of dimethylnitrosamine-induced rat kidney tumours and Ehrlich solid tumour in mice the increased migration of activated macrophages was associated with the average specific growth rate. The macrophage infiltration of tumours and systemic immune reactivity to tumour-associated antigens depend probably on tumour cell kinetics.     

Antiproliferative activity of difluoromethylornithine and the factors decreasing its effectiveness in malignant growth

The inhibitory effect of difluoromethylornithine (DFMO) synthesized by the authors on the activity of the ornithine decarboxylase (ODC) and proliferation of microbial and mammalian cells in vitro was studied. The in vivo growth of ascite plasmocytoma of solid melanoma B-16 cells in mice was also effectively inhibited by DFMO. But the antiproliferative activity of DFMO in solid tumours was substantially lower. Such a decrease in the antitumour activity may be associated with polyamines released from necrotic areas of solid tumours. As the tumour cells "catch" the vitally important metabolites, their effect inside solid tumours is turned against the tumour cells themselves. The second reason of the decrease in the DFMO activity is adsorption of polyamines on the erythrocyte surface.     

Modifying effects of changes connected with pregnancy on 1,2-dimethylhydrazine-induced carcinogenesis in rats

The modifying effect of pregnancy and lactation on carcinogenesis induced by single injection of 1,2-dimethylhydrazine to female rats 30 days before mating has been studied. The total incidence of malignant tumours in rats with pseudopregnancy, single pregnancy, pregnancy and lactation, repeated pregnancies was lower in comparison with virgin animals (75, 44, 68, 59 and 93%, respectively). Colon adenocarcinoma incidence in rats with single pregnancy or repeated pregnancies was lower than that in virgin rats (42, 49 and 76%, respectively). Protective effect was observed mainly in descending colon. The mesenchymal kidney tumours were not developed at all in rats with single pregnancy. In virgin animals it was 31%. The inhibition of tumour incidence in the liver (cholangioma, cholangiocellular carcinoma) was observed in rats with single pregnancy or pregnancy and lactation in comparison with virgin control (3, 5 and 24%, respectively).     

Effect of the epidermal growth factor on 1,2-dimethylhydrazine-induced carcinogenesis in the rat intestinal mucosa

The radioimmunological and radioreceptor methods have been used to show that sialadenectomy leads to the stable decrease of the epidermal growth factor (EGF) concentration in saliva and blood serum. The mean number of colon tumours per rat was significantly lower among the rats which had been sialadenectomized before injections of the carcinogen, than in the control. But a sharp stimulation of carcinogenesis in the duodenal mucosa was observed after sialadenectomy. The production of the alpha-transforming growth factor with the EGF-competing activity for the EGF-receptors was found in the chemically-induced rat colon tumours.     

Hemolytic resistance of erythrocytes in the development of experimental tumors

Peculiarities of variations in the mechanical resistance of erythrocytes from mice with tumours were studied depending on the growth stage of tumours (lymphoma NK/Ly and sarcoma S-37). The accumulation of erythrocytes with the increased mechanical resistance at the stage of rapid tumour development (on the 4 to 6th days) was revealed by the kinetic method of ultrasonic haemolysis. Quantitative parameters of ultrasonic haemolytic resistance of erythrocytes from normal and tumour-bearing mice were used as criteria for the red blood cell changes depending on the cell age in blood. The increase of haemolytic resistance at the rapid stage of tumour growth may be caused by a higher number of "young" erythrocytes in blood. Ultrasonic haemolytic resistance increases when there is no changes in the erythrocyte quantity and hemoglobin concentration. The kinetic study of ultrasonic haemolysis of the erythrocytes isolated from peripheric blood permits estimating the reaction of the blood forming organs to the origin and development of tumours.     

3H-thymidine incorporation into the DNA of the nucleic factor in the ascitic fluid of Ehrlich cancer

After intraperitoneal administration of 1.85 MBq 3H-thymidine to mice with Ehrlich ascites tumours the maximal radioactivity of nucleic factor DNA of ascitic fluid was observed when the isotope had been injected 5-6 days before extraction of ascitic fluid (4-5.10(5) cpm/mg). The maximal radioactivity of DNA of tumour cells themselves was registered when 3H-thymidine was administered 2 days prior to tumour ascites extraction (5.2.10(5) cpm/mg). The administration of even 37 MBq 3H-thymidine 1.5 h before the ascitic fluid extraction from the Ehrlich ascites tumours did not result in the incorporation of this radioactive precursor into nucleic factor DNA. The results obtained show that there is an interval (several days) between the nucleic factor DNA synthesis and its secretion.     

1,2-dimethylhydrazine induction of epithelial tumors of the kidneys in CBA strain mice

The results of experiments on the 1,2-dimethylhydrazine (DMH) induction of epithelial renal tumours in CBA male mice are presented. The dose-response study shows a sharp increase (from 5 to 75%) of the epithelial renal tumour incidence in the range of 2, 4 and 8 injections of DMH. Higher doses induce a decrease of the tumour incidence due to the early death caused by other tumours. DMH is shown to be the most powerful renal carcinogen in mice. Serial sacrifice of mice after 5 injections of DMH is a convenient model for the study of renal carcinogenesis in mice. Main histological types of epithelial renal tumours are illustrated.     

Ganglioside content and profile in the ovarian tumor tissues and in the biological body fluids of patients

Lipid-bound sialic acid (LSA) content and ganglioside composition in resected tumours and body fluids of patients with benign ovarian tumours, borderline ovarian tumours, ovarian cancer and also in unaltered ovaries of patients with uterine cancer were examined. LSA levels in tissues and relation of the main gangliosides GD3/GM3 progressively decreased from unaltered ovaries to ovarian cancer. Distribution of gangliosides GD3 and GM3 in the borderline tumours was not uniform. Absolute content of GD3 increased more than twice in profuse growth from the inner surface and decreased almost three times in the cyst capsule as compared to the intact tumour. Ganglioside GD3 content decreased in malignant ovarian tumours but increased in ascitic fluid of cancer patients as compared to GM3. These results suggest that ganglioside GD3 is shed more intensively in the borderline ovarian tumours.     

Effect of thiamine and its antimetabolite oxythiamine on the proliferative activity of carcinosarcoma Walker 256 cells

The microscopic studies of tumours from rats injected with thiamine at a dose of 20 mg/kg for 5 days have shown that sites of hemorrhages and necrosis are considerably more extensive than in tumours of control animals. Injections of the same doses of oxythiamine increase the rate of pathologic mitoses in tumour cells and decrease the tumour weight by 45%, limit the synthesis of thiamine diphosphate and inhibit the transketolase activity in tissues.     

Appearance of new transplantation antigens in tumor cells treated with RNA

Immunization of mice with the Wistar rat liver tissue increased their resistance to the subsequent intramuscular transplantation of Krebs-2 tumour cells preincubated with the rat liver RNA and did not affect the transplantability and growth of the same untreated tumour cells. The growth of the tumour cells pretreated with allogenic RNA did not differ from the growth of the untreated tumour cells when the mice were immunized with material genotypically different from the RNA tissue-source. When the immunizing tissue and RNA source were genotypically identical, the mass of the tumours growing in three tested mice strains (A/He, CC57BR, BALB/c) was 40-50% less than that of untreated tumours and the enhancement effect was observed in C3Hf mice. It is suggested that RNA preparations induce the appearance of the transplant antigens in tumour cells similar to those of RNA donors tissues. The effect of RNA preparations was abolished by RNAse incubation.     

Analysis of the antigenic specificity of cell subpopulations of Ehrlich ascites cancer

Antigenic differences between primary peridiploid Ehrlich tumour and subpopulations of tumour cells obtained from it on the 35th or 185th day of their growth were studied by the method of transplantation resistance. The development of peridiploid tumour in mice immunized with the peritetraploid subpopulation of cells and that of peritetraploid tumours in mice immunized with peridiploid subpopulation of cells evidences for alterations in specificity of antigenic tumour with an increase or decrease in its ploidy. Antigenic differences between karyotypically distinguishing subpopulations isolated from different tumour regions were revealed.     

Localization of embryonic prealbumin-1 in the tissues of human malignant tumors

The distribution of human embryonic prealbumin-1 (EPA-1) has been studied in 52 different malignant tumours using indirect immunofluorescent technique and two types of antibodies to different antigenic determinants: "EPA-1" and "EPA-1S". In mesenchymal tumours (except for desmoids and chondrosarcomas) this glycoproteid was observed in the cytoplasm of tumour cells, but "EPA-1S"--in the connective-tissue fibers only. Localization of glycoproteid EPA-1 depends on the type of the used primary antibodies. EPA-1 is also observed in the connective-tissue stroma of most of epithelial tumours. A conclusion is made that transformation of EPA-1 glycoproteid synthesis from definitive to fetal form occurs in malignant tumours.