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Biomedical subjects

V I Kaledin

Publications and source records attributed to V I Kaledin.

At least 37 records · Page 2Linked to original sources

Activity and concentration of cathepsin B as prognostic criteria for the development of mouse LS lymphosarcoma and Lewis lung adenocarcinoma.

We measured activity and content of cathepsin B in tumor tissues, liver, and spleen in mice with Lewis adenocarcinoma and LS-lymphosarcoma. Cathepsin B activity in Lewis adenocarcinoma cells was lower than in LS-lymphosarcoma cells, which was probably related to differences in their metastatic properties. Antitumor therapy increased activity and content of cathepsin B in tumor tissues. Changes in the content and activity of cathepsin B in tumor tissues can serve as a prognostic criterion for tumor regression during therapy. Cathepsin B is probably involved in apoptosis of tumor cells during chemotherapy of lymphosarcoma-LS with cyclophosphamide.

Animals↗

[Apoptosis-inducing and anti-tumor effect of cyclophosphamide, cisplatin and adriamycin used separately or combined in murine lymphosarcoma LS].

The investigation deals with antitumor effect of cyclophosphamide, platin and adriamycin on transplantable mouse lymphosarcoma LS. It was found that the effect of the most potent drug cyclophosphamide is mediated mostly by apoptosis, while those of platin and adriamycin--by apoptosis and necrosis of tumor cells. When a combination of two or three drugs was used the necrotic effect increased proportionally, while the apoptotic one decreased. However, the overall antitumor effect did not exceed that of the one drug which induced apoptosis most effectively.

Animals↗

Involvement of transcription factor HNF3gamma in the effect of o-aminoazotoluene on glucocorticoid induction of tyrosine aminotransferase in mice sensitive to its hepatocarcinogenic action.

In the rodent liver, hepatocarcinogens inhibit the glucocorticoid induction of several liver-specific genes, including tyrosine aminotransferase (TAT). A distinct positive correlation exists in mice between the extent of inhibition of TAT induction after acute administration of o-aminoazotoluene (OAT) and the frequency of liver tumors after chronic exposure to the carcinogen. To elucidate the mechanism of the carcinogenic action, the effects of OAT on the DNA-binding activity of several transcription factors participating in the glucocorticoid regulation of TAT gene expression were studied. The experimental inbred male mice were sensitive (A/He and SWR/J, tumor induction frequency of 75-100%, TAT induction inhibition of 35-50%) and resistant (CC57BR/Mv and AKR/J, 0-6% and 10-15%, respectively) to OAT. Gel retardation experiments showed that hepatocyte nuclear factor 3 (HNF3)gamma DNA-binding activity was strongly reduced in nuclear extracts from the livers of OAT-treated A/He and SWR/J mice but only slightly reduced in CC57Br/Mv and AKR/J mice. The DNA-binding activities of Ets, AP1 family members, and GME binding proteins were unaffected. HNF3gamma DNA-binding activity was reduced by 1 h after OAT administration and remained low for 1 mo, as did inhibition of TAT induction in the liver. These results suggested that the inhibitory effect of OAT on the glucocorticoid induction of TAT is mediated by reduced HNF3gamma DNA-binding activity.

Animals↗

Role of cystatin C and cysteine proteinases in the development of mouse LS-lymphosarcoma.

The growth of LS-lymphosarcoma in CBA mice was accompanied by a decrease in the content of the major extracellular inhibitor cystatin C in the tumor, plasma and, to a lesser extent, in tissues not involved in tumor process (liver and spleen). Cyclophosphamide in a dose of 50 mg/kg prolonged the life-span of animals and decreased tumor size by 80%. Cathepsin B and L activities in the tumor tissue increased by 3 and 7 times, respectively. Cystatin C content in the tumor tissue, spleen, and plasma also increased. Cystatin C assay in tumor tissue and plasma helps to predict the rate of tumor growth and to evaluate the efficiency of antitumor therapy.

Animals↗

Macrophage Stimulator beta-(1-->3)-D-carboxymethylglucan improves the efficiency of chemotherapy of Lewis lung carcinoma.

We studied the effect of macrophage stimulator water-soluble beta-(1-->3)-D-carboxymethylglucan on the efficiency of cyclophosphamide chemotherapy in Lewis lung carcinoma. Cyclophosphamide inhibited the growth of primary tumor nodes by 57%. The preparation possessed pronounced antimetastatic activity: metastases were found in 40.9% animals. Combination therapy with cyclophosphamide and (1-->3)-beta;-D-glucan inhibited the growth of intramuscular tumors by 75-89% and reduced the incidence of metastases into the lungs by 92-94%. The therapeutic effect was most pronounced after simultaneous administration of these preparations: tumor growth was suppressed by 89.3% and metastases were found in only 7.5% animals (vs. 100% in the control). The potentiating effect of beta-(1-->3)-D-carboxymethylglucan is related to accumulation of cysteine proteinase inhibitors in the tumor tissue and plasma, but not to changes in blood cell composition.

Animals↗

Chitotriosidase as a marker of macrophage stimulation.

Serum chitotriosidase activity was determined in different conditions accompanied by macrophage stimulation. Stimulation of macrophages with zymosan, yeast polysaccharide carboxymethylglucan (fraction II), and lysosomotropic preparation Triton WR-1339 1.5-2.0-fold increased enzyme activity. Chitotriosidase activity in intact Wistar rats was similar to that in humans, while in CBA and A/Sn mice this parameter was 5-fold higher. Sharp increase in chitotriosidase activity in the serum from patients with type I Gaucher's disease was probably related to intense secretion of the enzyme by macrophages. Under experimental conditions, stimulation of rat and mouse macrophages (mainly liver cells) caused no increase in chitotriosidase activity typical of patients with Gaucher's disease.

Adolescent↗

[Cyclophosphamide-induced apoptosis of murine lymphosarcoma cells in vivo].

The antitumor action of combination chemotherapy (cyclophosphamide + adriamycin + vincristin + prednisolone) for transplantable nitrosomethylurea-induced lymphosarcoma was studied in male CBA mice. Single injections of the mixture were followed by complete regression of tumors of up to 2 cm in diameter. The effect was shown to be caused by cyclophosphamide (CP) alone, by inducing apoptosis. The other components failed to potentiate the CD effect. Being useless, they are likely to cause harm by contributing to the overall toxic effect of therapy. The nature and duration of CP-induced remission appeared dose-dependent: on day 50 of the administration of 50, 100 and 150 mg/kg body, tumors were detected in 100, 55 and 0% of the animals, respectively. Such means of apoptosis induction as glycocorticoid treatment and ionizing radiation did not cause complete regression.

Animals↗

Chitotriosidase as a new marker of macrophage stimulation in a tumor model treated with cyclophosphamide and Ukrain.

Ukrain has previously been demonstrated to exert a malignotoxic effect in vivo. This antitumor drug has been effective in the treatment of some malignancies in experimental animals as a result of immunostimulation (macrophage stimulation). In the present study, serum chitotriosidase activity was measured as a biochemical marker of macrophage stimulation in several murine and rat models of macrophage stimulation. It was shown that zymosan, carboxymethylated glucan and Triton WR 1339 administration to CBA mice or Wistar rats was followed by a considerable increase in serum chitotriosidase activity. Murine LS lymphosarcoma development decreased serum chitotriosidase activity. Antitumor treatment by Ukrain or cyclophosphamide did not restore this index to the normal value.

Alkaloids↗

Cystatin C in LS lymphosarcoma and HA-1 hepatoma treated with Ukrain and cyclophosphamide and involvement of apoptosis.

The concentration of cystatin C, a cysteine proteinase inhibitor, was measured during the treatment of murine LS lymphosarcoma with cyclophosphamide and HA-1 murine hepatoma with the antitumor drug Ukrain. It was shown that concentrations of cystatin C were very low in both the tumor tissues studied (HA-1 hepatoma cells and LS lymphosarcoma); increased cystatin C concentrations were found only in Ukrain-treated murine hepatoma, suggesting the mechanism of antitumor effect of this drug. Cyclophosphamide treatment in LS lymphosarcoma did not influence the concentration of cystatin C in tumor cells. At the same time, a marked increase in cathepsin B and cathepsin L activity in LS lymphosarcoma was found, indicating the involvement of apoptosis in the mechanism of antitumor action of cyclophosphamide. While the DNA from untreated LS lymphosarcoma was very homogenous and its molecular weight was high, the DNA from tumors of treated mice broke down, giving rise to the ladder figure characteristically produced by cells dying from apoptosis. Evidence was obtained that cyclophosphamide-induced tumor regression was effected by apoptosis.

Alkaloids↗

Influence of Ukrain and cyclophosphamide administration on HA-1 murine hepatoma and LS lymphoma on aspartic proteinase cathepsin D.

Cathepsin D, the major lysosomal aspartyl proteinase and a mediator of interferon-gamma and tumor necrosis factor-alpha-induced apoptosis, was studied in murine models of LS lymphosarcoma treated by cyclophosphamide (possible apoptosis induction), and HA-1 hepatoma treated by Ukrain (positive antitumor effect). It was found that cyclophosphamide, as well as cyclophosphamide plus Ukrain, increased cathepsin D specific activity in mice with LS lymphosarcoma. Ukrain alone had no effect on cathepsin D activity in LS lymphosarcoma. In HA-1 hepatoma cells cathepsin D activity was not changed compared with intact normal murine liver (day 10) and activity decreased during tumor development (on day 12). Ukrain significantly increased cathepsin D activity in ascitic fluid (day 10) and had a tendency to increase cathepsin D activity in ascitic cells but not to the normal value.

Alkaloids↗

Cysteine proteinase inhibitor level in tumor and normal tissues in control and cured mice.

Cystatin C is the best known extracellular endogenous cysteine proteinase inhibitor and has been studied as a possible index of tumor growth and as a marker of the effectiveness of antitumor therapy. The aim of this study was to evaluate cystatin C concentrations in murine tumor tissues (compared with other organs not directly involved with tumor development, such as the liver and spleen) during treatment with several antitumor drugs (Ukrain and/or cyclophosphane). Cystatin C concentrations in murine tissues and biological fluids was determined by enzyme-linked immunosorbent (ELISA) assay. The cystatin C ELISA test is a sandwich immunoassay, which uses immobilized rabbit antihuman cystatin C Pab and mouse antihuman cystatin C Mab-HRP (monoclonal antibodies, conjugated with horseradish peroxidase). We observed decreased serum cystatin C concentrations compared with controls in all nontreated tumor models: HA-1 hepatoma (solid and ascitic forms), lung adenocarcinoma (solid and ascitic forms) and LS lymphosarcoma. In the ascitic fluid of mice with HA-1 hepatoma the cystatin C concentration was much lower than in the serum of the same mice (about 20-fold lower). In the HA-1 model of hepatoma cells cystatin C concentration decreased about 2-3-fold compared with the control (intact liver) and Ukrain significantly increased the cystatin C concentration. Cyclophosphane treatment of LS lymphosarcoma significantly increased the cystatin C concentration in serum. Cyclophosphane treatment (50 mg/kg, single injection) increased cystatin C by up to 8-fold more in tumor issue. Ukrain treatment of LS lymphosarcoma was also followed by increased levels of cystatin C in tumor tissue (4-fold); cyclophosphane plus Ukrain had a similar positive effect. In the group with LS lymphosarcoma Ukrain or cyclophosphane plus Ukrain treatment induced a significant increase in cystatin C concentration in liver. Liver cystatin C concentration decreased in the HA-1 hepatoma group and treatment with Ukrain or carboxymethylated beta-1, 3-glucan (CMG) increased this index in both groups. Spleen cystatin C concentrations decreased about 5-fold in LS lymphosarcoma compared with controls and combined treatment with cyclophosphane plus Ukrain restored the index to the normal value. We can conclude that both murine tumors studied were characterized by low cystatin C concentrations in tumor tissues and decreased cystatin C concentrations (to a lesser degree) were also observed in liver and spleen as a result of the "toxic" effect of tumor bearing. Effective treatment in all cases (especially with Ukrain or a combination of cyclophosphane plus Ukrain) induced a significant increase in cystatin C. Obviously, the decrease in cystatin C concentration predominantly in tumor tissue was connected with tumor development and restoration of cystatin C level may be used as a marker of efficacy of antitumor therapy.

Alkaloids↗

[The study of correlation between the K-ras genotype and murine susceptibility to chemically induced lung neoplasms].

The susceptibility of the ICR, DD/He and CC57/BR mice to urethane-induced lung tumors was analyzed in comparison with the A/He (highly susceptible) and AKR (resistant) lines of mice. Allelic variants of the K-Ras gene intron 2 in these lines have been determined. Susceptibility of the ICR mice was similar to that of the A mice, and intron 2 of the K-Ras ICR gene carried the 37-bp deletion analogous to that described in the A/He line. The DD mice intron 2 also contained the deletion, but despite the presence of the "susceptible" K-Ras allele, the DD/He mice were resistant to urethane induction of lung tumors. The CC57BR line carried the deletion and demonstrated relatively high susceptibility. Our findings indicate that the K-Ras gene may be important in the chemical induction of lung tumors.

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