DNA and protein syntheses in mouse kidney cell cultures infected with polyoma virus were studied by means of autoradiography. A combined observation, which allows immunofluorescence and autoradiography to be undertaken on the same cell, was also carried out to elucidate the relationship between viral antigen and DNA syntheses.
It was found that the increase in DNA synthesis in the infected cell cultures could be attributed largely to viral DNA synthesis. Protein synthesis, as determined by the incorporation of tritiated leucine as an index, was found to occur continuously both in the infected and non-infected cell cultures. Nuclear and nucleolar incorporation of leucine into protein was found to be greater in the infected than in the non-infected cells. A prominent nucleolus, known to be characteristic of the polyoma virus-infected cell, was considered to be the morphological expression of the increase in protein synthesis. It is suggested that the synthesis of viral DNA generally precedes synthesis of viral specific protein.

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Lung cancers, uterine sarcomas, and carcinomas were induced by the repeated subcutaneous injections of 4-nitroquinoline 1-oxide in a mixture of olive oil and lecithin. The incidence of lung cancer was very much lower than in the previous experiments. The incidence of uterine tumors was 27.8% of the effective number of animals. Squamous cell metaplasia in the uterine glands and hypertrophy of the cervical epithelium were also observed.

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The tumor-inhibiting effect of polysaccharide fraction isolated from bamboo leaves was found to be just as marked when the treatment was given prior to tumor implantation as when it followed tumor implantation. Taken together with already established lack of general toxicity and especially of cytocidal action on the part of the bamboo polysaccharide, the marked effectiveness of pretreatment demonstrated in the present study may be regarded as showing that here we may be dealing with an indirect and, therefore, host-mediated antitumor effect.
Effect of pretreatment with certain other plant polysaccharides on the growth of subsequently implanted tumor was also tested, mainly for the sake of comparison.

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In a series of dimethanesulfonylthioalkanes (DST-alkanes) tested, DST-propane, -butane, and -pentane showed antitumor effect on the solid form of Ehrlich carcinoma but not on the ascites form of the same carcinoma. Since these compounds also showed inhibitory effect on respiration, glycolysis, and phosphatase activity of Ehrlich carcinoma cells, it was thought that some relationship might exist between the antitumor effect and inhibitory effect on the enzymatic activity in vitro in a series of DST-alkanes. Unlike a series of dimethanesulfonylhydroxyalkanes (DSHA), DST-alkanes did not show any relationship between toxicity and number of carbon atoms. It may therefore be said that the mechanism of action of DST-alkanes which are isoster with DSHA should differ from that of DSHA.

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Effect of some polyhydroxy-alkylpteridines on the development of liver cancers in rats fed with 4-dimethylaminoazobenzene (DAB) was studied, using 2-amino-4-hydroxy-6-trihydroxybutyl-L-erythro-pteridine (rhamnopterin) and 2-amino-4-hydroxy-6-tetrahydroxybutyl-D-erythro-pteridine (glucopterin) in comparison with succinic acid. Oral administration of rhamnopterin bad a powerful retarding effect on liver cancer in rats fed DAB, but glucopterin bad no effect.

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Changes in the liver of rats fed 3'-methyl-4-dimethylaminoazobenzene for more than 2 months were histochemically studied by means of the acid hematein test for phospholipids and Sudan Black-B method for lipids.
It was found that the reactivity of hepatic cells to the acid hematein test diminished gradually in the course of azo dye feeding; hyperplastic cells of type I and II, and hepatic carcinomas as well exhibited less affinity to acid hematein in a decreasing order.
Changes in the adrenals of azo dye-fed rats were also studied by means of the chromaffin and iodate reactions for medullary hormones and Sudan Black-B method for cortical lipids. No definite relationship was found between carcinogenic changes in the liver and histochemical changes in the adrenal.

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Histogenetical observations were made on pulmonary tumors, adenomas and adenocarcinomas, in Swiss-strain mice induced by the subcutaneous injection of 4-nitroquinoline 1-oxide. It was demonstrated that some adenomas arise from alveolar cells (19.8%), and others from epithelial cells in the area where the terminal bronchioli pass into the alveolar ducts (56.2%), while most of adenocarcinomas arise either from the adenomas originating from bronchioli (13.5%) and others directly from the bronchial terminals (9.4%). One adenocarcinoma was found originating from subpleural adenoma (1.0%).

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This paper describes the effect of crude extracts from garlic (Allium sativum f. pekinense) and its related species, A. bakeri, A. cepa, A. fistulosum, and A. victorialis subsp. platyphyllum, on MTK-sarcoma III, an ascites sarcoma of albino rats. Of the plants tested, the extract from garlic exerted the most marked antimitotic effect on tumor cells. Cytologically the effects of this plant were much like those induced by colchicine, by producing blockage of metaphase cells and scattering, as well as abnormal condensation of metaphase chromosomes.
Extracts from A. victorialis and A. cepa produced effects similar to those of garlic, though their action was not very severe. The cell-damaging action of the extracts from A. bakeri and A. fistulosum was much less than extracts from above plants.

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Liver neuraminidase activity was assayed using a newly deviced method for determination of sialic acid which is principally based on the combination of column-chromatographic separation and thiobarbituric acid reaction, Marked elevation of neuraminidase activity was found in the liver of tumor-bearing mice and rats. A slight elevation of the enzyme activities in brain and kidney was noticed in tumor-bearing hosts. Biological significance of the phenomenon was discussed from the point of tumor-host relationship.

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Supravital staining with Neutral Red was carried out on the cells of 50 different transplant-strains of ascites tumors. The distribution of Neutral Red granules (NRG) in their cytoplasm was classified into 3 different types; rosette (type I), mixed (type II), and scattered (type III). Rat ascites hepatoma strains which were characterized to be free-, mixed-, and island-cell type in their ascitic features showed rosette, mixed, and scattered types, respectively, in the NRG distribution. There was a close similarity in the NRG distribution between Yoshida sarcoma cells and the cells of free-cell type of ascites hepatoma strains. Rat ascites hepatomas, AH-39, AH-423, and AH-130FN, or mouse ascites tumors, Ehrlich carcinoma, hepatoma MH-134, and leukemia SN-36 cells were pointed out as the exceptions from the others because there was no correlation between their NRG distribution and their ascitic features. A comparative observation on the NRG distribution was also carried out between the cells of several sublines or variant strains and their mother strains, and between tumor cells and some kinds of normal cells.

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Histochemical changes in the liver of adrenalectomized or hypophysectomized rats were investigated by means of the section freeze-substitution technique after Chang and Hori.
It was observed in livers of adrenalectomized or hypophysectomized fasted rats that glucose-6-phosphatase and phosphorylase activities and glycogen content decreased without any detectable change in the activity of cytoplasmic ATPase and succinic dehydrogenase.
Prednisolone sodium hemi-succinate and insulin showed no effect on the activity of glucose-6-phosphatase and succinic dehydrogenase of liver slices in vitro.

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