235 male rats of the Wistar strain and the mixed stock were maintained on the rice diet containing sodium carbonate, fish powder and cod liver oil and 20-methylcholanthrene emulsion in polyethylene glycol administered orally, in drinking water for as long as 223 days. The morphological changes in the antrum of the glandular stomach of rats, such as the erosion of the mucus membrane, the tubular elongation of the crypt and the excavation lined with the new-epithelium with eventuated in the adenomatous growths of the glandular stomach are described. The majority of the adenomatous growths were composed of atypical glandular cells derived from the mucosa. These gastric lesions appeared to be confined to the chamber of the glandular stomach, and no remarkable change resulted in the part of the forestomach. However, no carcinoma was produced. At the present moment, it is an open question whether these adenomatous growths are precancerous, preceding the overt adenocarcinoma.

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[in Japanese]

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This study deals with the effects of podophyllotoxin, alpha- and beta-peltatin and quercetin, all being crystalline compounds isolated from podophyllin, on cell division in the ascites tumors of rats and their influene on the growth of tumors. By the application of every chemical at appropriate dose levels, the temporary suppression of tumor growth was induced to a greater or less degree in experimental animals as a result of damage to a large number of the tumor cells. But some of the tumor cells remain unaffected by the action of chemicals in every case. These resistant unaffected tumor cells constitute the primary source of the subsequent growth of malignant cells leading to the reappearance of the tumor in the treated animals. No complete inhibition of growth of the tumor has been observed.
It was shown that the four compounds isolated from podophyllin were not identical in the order both of activity and of toxicity.

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A fluid tumor, probably a sort of lymphatic leukemia developed spontaneously in a mouse of the B-strain. The mouse showed an expansion of the body cavity resulting from an accumulation of ascites containing large numbers of lymphoid cells. Some visceral organs such as the liver, kidney, and spleen showed a remarkable infiltration with tumorous cells; there was also a tumorous mass found in the dorsal side of the peritoneal cavity. After several trials it was found that this fluid tumor was non-transplantable. The non-transplantability of this tumor may probably be due to the absence of the stem-line cells which contribute to the growth of the tumor in transplantation.

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1) The enzymatic desamination of 13 homologous fatty acid amides and 2 ω-phenyl fatty acid amides in the liver extract of rats on hepatic carcinogens, 4-dimethylaminoazobenzene or 2-acetylaminofluorene, has been investigated.
2) Aqueous homogenate of normal liver had the marked activity to evolve ammonia from the above mentioned substrates, although the amount differed according to the sorts of substrates employed.
3) The pathological but non-cancerous liver showed the appropriate activity even in the case of marked alteration, as long as the neoplastic transformations had not taken place.
4) Hepatoma had very low activity, scarcely reaching about 1/4 to 1/30 that of normal liver according to the sorts of substrate employed.
5) So far as the straight chained fatty acid amides which could be used as aqueous solutions are concerned, the more easily they were cleaved by liver extracts the richer they are in carbon atoms, and the straight chained compounds were decomposed more readily than the branched with corresponding molecular weight.

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1) Activity of choline oxidase in the hepatic tissues of rats fed carcinogens, 4-dimethylaminoazobenzene (DAB) and 2-acetylaminofluorene (AAF) was investigated.
2) The choline oxidase activity of the abnormal but non-neoplastic hepatic tissues showed similar height as that of normal liver, and when the grade of lesions developed to cirrhosis still maintained the moderate lebel although there occurred some indication of lowering. On the contrary as soon as hepatic tissues have once turned neoplastic they showed the extremely low activity, which was less than about 1/10 of normal lebel.
3) The choline oxidase activities decreased every week immediately after the experiment had been started, and reached the bottom at the 3rd or 4th week of feeding and were about 1/3 of the normal lebel.

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[in Japanese]

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In confirmation of Hargreaves and Deutsch, we found that tumor kocksaft factor clearly inhibits in vitro the activity of the solution of crystalline catalase, but it was also demonstrated that kocksaft prepared from normal liver, spleen, kidney, embryo, etc., brings about similar degree of inhibition. These facts, taken together with the inability of a potent toxohormone fraction to produce in vitro inhibition of crystalline catalase solution, seem conclusive in showing that the so-called kocksaftt factor is an entirely different entity from toxohormone.

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By testing a long series of quinone derivatives for their tumoricidal action on NF sarcoma in vitro, and for their inhibiting action on Ehrlich ascites carcinoma in vivo, it was demonstrated that certain thio-quinone derivatives show significant anti-cancer effects.

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1) By X-irradiation in vitro in the presence of O₂, the -SH content of isolated liver mitochondria was oxidized and succinoxidase activity was inhibited slightly in accordance with the extent of oxidation of the -SH content, but was reactivation by GSH.
2) X-irradiation impaired the oxidative phosphorylation activity of isolated mitochondria strongly in succinate system; lesser in β-hydroxybutyrate system, and in the former case GSH could reactivate phosphorylation ability almost completely. In contrast, ATP-ase activity of mitochondria was activated by irradiation. The inconsistancy with Barron's results was discussed.
3) The -SH content of chromosome preparation decreased after irradiation only in the presence of O₂, and the significance of this result in relation to chromosome aberration was discussed.
4) The protective effect of thiosulfate and taurine for whole body irradiation of rats were examined in comparison with that of cysteine, and the former was found to be effective in protecting -SH content of spleen and the latter most excellent for preserving spleen DNA contents.

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