Methotrexate and folic acid effect in normal and sarcoma 180 bearing mice.

Four- to six-fold surplus of folic acid in oral application reduced the toxicity of methotrexate administered repeatedly in high therapeutic doses. The therapeutic effect of methotrexate applied intraperitoneally to mice with the ascitic S 180 sarcoma, as measured by their survival, can be reliably demonstrated; moreover, the survival can be prolonged by adding folic acid into drinking water. In the solid form S 180 the intraperitoneal administration of methotrexate did not significantly reduce the weight of tumors of treated aminals as compared to untreated animals. The maximum tolerated dose of methotrexate was lower in animals with the ascitic tumor than in non-tumorous animals.

Changes in hemopoiesis of mice of the C3H strain following transplantation of Gardner lymphosarcoma and infection with LDH-virus. III. Blood proteins.

Inoculation of bone marrow and spleen cells of C3H/Sumice strain mice demonstrated that on the ninth day of growth of Gardner lymphosarcoma these tissues were invaded with tumor cells. The weights of mice with advanced tumors increased. Yet the deterioration of health status of mice is characterized by decreased food and water consumption, as well as by lower concentrations of proteins in mouse sera and plasma. The albumin fraction shows a remarkable drop. These changes could not be detected in tumor free mice following LDH-virus infection. The treatment with L-asparaginase influenced the manifestations of tumor growth, but not the effectivity of LDH-virus contaminating the tumor as demonstrated by the increased activity of lactate-dehydrogenase in the mouse sera.

Changes in hemopoiesis of mice of the C3H strain following transplantation of Gardner lymphosarcoma and infection with LDH-virus. I. Circulating blood.

The values of red and white blood count, of spleen and liver weight were determined in mice of the C3H strain after transplantation of Gardner solid lymphosarcoma contaminated with LDH-virus and after infection of LDH-virus, and compared with those found in normal intact mice. Special attention was devoted to early post-transplantation period and the final stage of tumor growth. The second day after infection of mice with LDH-virus, leukopenia with marked lymphopenia was observed, together with a reduced number of reticulocytes and spleen enlargement. The same changes became more pronounced in tumorous mice on the second posttransplantation day. The changes--with the exception of spleen enlargement--following LDH-virus infection became normalized within the period of the final stage of tumor growth. Contrarily, in mice with tumors in the final stage of the disease besides spleen enlargement also the reduced erythrocyte counts, leukopenia with pronounced lymphopenia and thrombocytopenia were found.

The chemotherapy of C3H mice bearing Gardner lymphosarcoma with bovine fibrinogen-methotrexate derivative.

Derivative of bovine fibrinogen (FBG) containing chemically bound methotrexate (MTX) has been prepared by action of ethyldimethylaminopropyl carbodiimide. The derivative retained its solubility and clotability. Intraperitoneally administered FBG-MTX derivative one day after transplantation of the ascitic Gardner lymphosarcoma prolonged distinctly the survival of C3H mice. The intravenous application of FBG-MTX derivative to mice bearing the solid form of the tumor exerted chemotherapeutic effect resulting in prolongation of survival. The local application of FBG-MTX solutions followed by injection of thrombin resulted in the formation of a fibrin clot in the tumor area which persisted at least 48 hours. Local chemotherapy of the solid tumor with fibrin clot containing MTX performed on day 1 or 3 led to significant prolongation of survival of the treated animals. Mechanism of MTX liberation and the possible application of FBG-MTX derivative in chemotherapy of tumors are discussed.

Changes in hemopoiesis of mice of the C3H strain following transplantation of Gardner lymphosarcoma and infection with LDH-virus. II. Spleen and bone marrow.

Cytological examination of spleens of mice with growing Gardner lymphosarcoma contaminated with LDH virus indicates the augmentation of erythropoiesis and granulopoiesis, as well as the decrease of lymphopoiesis. Similar changes were observed after infection with LDH-virus. The counts from the bone marrow smear showed more pronounced changes only in tumorous mice, in which repeatedly increased granulopoiesis was found. When the mice bearing Gardner lymphosarcoma were treated with L-asparaginase, then the cytological findings in the spleens and marrows of femors were almost normal. The examination of spleen and bone marrow smears revealed no tumor cells. Histologically examined spleens of mice with 12-day-growing Gardner lymphosarcoma demonstrated infiltration of the follicles with tumor cells. In the marrow of sternum no infiltration of tumor cells could be established.

Distribution and pharmacokinetics of methotrexate in localized chemotherapy of solid Gardner's lymphosarcoma.

Pharmacokinetics and organe distribution of Methotrexate (MTX) in Gardner lymphosarcoma bearing C3H mice was investigated following two ways of drug administration: 1. intraperitoneal injection, 2. intratumoral implantation of 2-hydroxyethylmethacrylate gel with sorbed Methotrexate (localized chemotherapy). The highest level of MTX in blood appeared 2 hours after intrperitoneal injection but 7 hr after localized intratumorous application. Following intraperitoneal application the drug level in tumor reached its maximum two hours after injection; after 7 hr the drug could not be detected any longer. The localized chemotherapy led to six times higher concentration of the drug in the tumors as compared with the intraperitoneal application. This high level persisted for 17 hr and decreased moderately for 48 hr. MTX was accumulated in liver after both modes of administration with a half life 6.1 hr after intraperitoneal injection and 12.4 hr after the localized chemotherpay, respectively.

Effect of the alpha globulin fraction on the survival time of C3H mice (C3H/Sumice and C3H/VUFB) with a solid Gardner lymphosarcoma.

The effect of the alpha globulin fractions of human serum administered before the inoculum of tumour cells was studied in two sublines of C3H mice (C3H/VUFB and C3H/Sumice) showing a different resistance to a solid Gardner lymphosarcoma. The survival time of animals was shortened in both sublines, but more markedly in C3H/VUFB mice that were more resistant to the tumour. The survival was found to depend on the dose and the immunosuppressive activity of the alpha globulin fractions as revealed in other in vitro and in vivo tests. We believe that the tumour model using C3H/VUFB mice may be used as a further test for determining the activity of alpha globulin fractions.

[Toxicity of silica-gel polymers]. / Toxicita silikagelových polymeru.

Mice of the ICR strain were tested for the effect of intraperitoneally applied polymers of silicagel. Silicagel applied in the form of spherical-shaped particles caused local irritation and resorptive reaction with granulocytes. There was also renal damage of the type of necronephrosis and signs of necronephrosis.

Localized chemotherapy of Gardner's lymphosarcoma of C3H mice using combinations of carrier-sorbed antifolics and detoxicating tetrahydrofolates.

The effect of aminohexyl-2-hydroxyethylmethacrylate polymer (HEMA-Hex) with sorbed methotrexate (MTX) or 3',5'-dibromoaminopterin (BrAP) on the survival of C3H mice with Gardner lymphosarcoma was studied. The measured bits of HEMA-Hex-MTX or HEMA-Hex-BrAP were implanted into the solid tumor growing 4 to 8 8 days. The doses of sorbed antimetabolites amounting in MTX 4.3 to 13.5 mg.kg-1 and in BrAP 5.1 and 12.6 mg.kg-1 were calculated from the area of the carrier and mean weight of animals. Following implantation i. p. injections of leucovorin or anhydroleucovorin were applied. The treatment of early tumors showed better results than that of advanced ones if evaluated either as prolonged survival or as a number of mice surviving the observation period. The 18-hr. interval between implantation of HEMA-Hex-MTX and anhydroleucovorin injection was optimum if considered both the protection of mice from lethal MTX toxicity and therapeutic effect measured as prolonged survival. Doses of leucovorin or anhydroleucovorin close to MTX doses in term mg.kg-1 resulted in best results. In case leucovorin was applied to tumor-bearing mice pretreated with HEMA-Hex with nonlethal dose of MTX, the survival of mice was shortened. Folic acid did not show this effect. Intra-tumorous implantation of HEMA-Hex-BrAP toxicity even if applied into an advanced tumor. The therapeutic effect of the sorbed BrAP seemed to decrease with tumor progression at a lower rate than of that the sorbed MTX. The application of anhydroleucovorin after implantation of HEMA-Hex-BrAP shortened the survival of tumor-bearing mice.