The effect of irradiation on the growth of human laryngeal tumors transplanted under the kidney capsule of immunocompetent mice

A study was made of the influence of gamma-radiation on the growth of human larynx squamous cell carcinoma transplanted under the capsule of the kidney of immunocompetent mice. The transplants were shown to increase in size 6 days after transplantation. Irradiation of animals 24 h after transplantation inhibited considerably the tumor growth. However, the preirradiation (24 h before operation) inhibited the growth of nonirradiated transplants to the same extent as the exposure of mice with the transplanted tumor fragments did: the radiation dose that induced 50% inhibition of the growth was 4.5 Gy and 5.3 Gy, respectively. Preliminary data indicate that tumor fragment of patients with the unfavourable prognosis increase in size and respond to radiation to a lesser extent.     

Hematopoietic tissue reactions associated with the growth of syngeneic transplanted tumors in mice]

Hemangiopericytoma growth in syngeneic male mice F1 (CBA X C57BL/bj) led to regular hemopoietic changes: an increase in the spleen weight, spleen cell count, in the number of colony-forming units (CFU). It also induced augmentation of myelopoiesis in the spleen and leukocytosis with a sharp increase of segmented granulocytes in the circulating blood characterized as the "leukemoid reaction" syndrome. The latter occurred even when the tumour cells were transplanted into the splenectomized host. Although less marked, this leukemoid reaction was also noted in advanced hepatoma transplanted to syngeneic male mice F1 (CBA X C57BL/6j). No leukemoid reaction was observed in these mice after grafting syngeneic strain of urinary bladder carcinoma.     

Effect of thermal environment upon transplanted tumors and growth of mice.

Ehrlich ascites tumor cells were inoculated subcutaneously in the dorsal, interscapular region of three groups of mice that were subsequently maintained in normo-, hypo- or hyperthermic environments. The controls, mice that had homologous whole spleens or thymic glands implanted in the same location, were maintained in a normothermic environment. Number of tumors established, their weights and volumes, and weights of animals were compared as well as tumor temperature, which was compared to brown fat and core temperatures.(1) The percentage of animals developing tumors was independent of environment. (2) Mice with tumors, and mice in which tumors did not take, gained more weight at the normothermic temperatures (21 °C) than at either 31 or 5 °C. (3). When the weight and volume of tumors are expressed per gram of mouse body weight, there is no difference between the hypo- and normothermic environments, but the weights and volume of tumors in a hyperthermic environment are only 36 and 58% respectively of the tumors in normothermic animals. (4) Tumor temperatures are about 1 °C cooler than the underlying brown fat regardless of environment, and brown fat was 0.5 °C cooler than the core temperature. (5) Transplanted thymus glands and spleens become encysted after 31 days; they proved to be cooler than the malignant tumors.     

Metabolic pool of purine compounds in erythrocytes of mice during growth of transplanted tumors

The pattern of purine derivatives was studied in the erythrocytes of C3HA and ICR mice during Hepatoma 22 and Ehrlich ascites tumor cells growth. Host erythrocytes purine nucleotides, nucleosides and bases were affected by the implanted tumors. The results indicated that the host erythrocytes markedly concentrated adenine and guanine nucleotides on the 5th and 11th-12th day of tumor growth. By contrast, content of nucleosides and bases were sharply decreased during the log growth phase (5th day) with the restoring of these precursors within the 11th-12th day (plateau phase). These observations indicate that aspects of the purine compounds metabolism in host erythrocytes are linked with tumor development.     

The effect of oxytetracycline on insulin resistance in obese mice

1. Chronic oxytetracycline treatment was found to improve the insulin resistance of the obese-hyperglycaemic mouse. 2. The improved response to insulin was accompanied by decreased concentrations of circulating insulin and glucose, by a decrease in the lipid content of the liver and by an increase in the insulin-receptor sites of the liver and adipose tissue. 3. The increase in insulin-receptor sites preceded the fall in blood glucose. 4. Comparable studies done on food-restricted animals indicated that although chronic food restriction corrected the hyperinsulinaemia it did not restore the insulin-receptor sites or the hyperglycaemia.     

Effect of chemo- and radiotherapy on the growth of human strains of respiratory and excretory organ tumors transplanted in athymic mice

The effect of single and five-fold administration of 12 chemotherapeutic drugs on human strains of larynx, lung and kidney cancers and Wilms' tumor transplanted in nude mice was studied. Wilms' tumor was found to be more responsive to dactinomycin and cyclophosphamide. Larynx, lung and kidney cancers were resistant to all the chemotherapeutic drugs studied. The effect of irradiation of larynx cancer which resulted in short-term tumor growth retardation was also studied.     

The effect of bovine growth hormone on growth of mammary tumors in hypophysectomized rats

Bovine growth hormone has been shown to be effective in promoting growth of mammary tumors in hypophysectomized rats treated with 7, 12-dimethylbenzathracene.     

Effects of Hydrocotyle sibthorpioides extract on transplanted tumors and immune function in mice

This paper describes the effects of an ethanolic extract of Hydrocotyle sibthorpioides on transplanted tumors and immunologic function in mice. When the H. sibthorpioides extract was administered orally at a dose of 1.5 or 3.0 g/kg body wt./day for 10 days, the inhibition rates for murine hepatic carcinoma clone (Hep), sarcoma 180 crocker clone (S(180)), and uterine cervical carcinoma clone (U(14)) were significantly enhanced. The antitumor activity of H. sibthorpioides is comparable to that of the common antitumor agent 5-fluorouracil. Also, our results indicate that the H. sibthorpioides extract promoted the thymus and spleen indices, and humoral immunity of mice. These observations demonstrated that H. sibthorpioides exerted a potent inhibitory effect on the growth of tumors, in addition to mediating immunomodulatory effects in mice.