Biochemical effect of 4, 5-bis(ethyleneimino)-1, 2-benzoquinone (OBE), 2, 5-bis-(ethyleneimino)-1, 4-benzoquinone (PBE), 4-ethyleneimino-1, 2-naphthoquinone (NQE), and other quinone derivatives was investigated on Ehrlich ascites carcinoma cells. OBE, PBE, and NQE inhibited the glycolysis and respiration at 10^-4M and inhibitory activity of these compounds on anaerobic glycolysis was proportional to their antitumor activity. Hexokinase activity in acetone powder on Ehrlich ascites carcinoma cells was markedly inhibited by OBE, PBE, and NQE at 10^-4M. Alkaline phosphatase activity was inhibited more strongly by hydroquinone, catechol, and p-benzoquinone than OBE and PBE at 10^-3M. Acid phosphatase activity was slightly enhanced by all the compounds tested. Cholinesterase activity in horse serum was enhanced by OBE, which showed a potent antitumor activity and reduced by NQE, showing no antitumor activity. It may therefore be said that the inhibitory effect of anaerobic glycolysis should be marked as one of the mechanisms of antitumor action of OBE.

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Yoshida sarcoma AH-130 and AH-7974 were inoculated intraperitoneally into rats. The periodical light and electron microscopic observations on the effect of Nitromin (50mg/kg) revealed prominent changes of organellae, swelling, cristolysis, and cristorrhexis of mitochondria, destruction and decrease in the amount of membrane system of endoplasmic reticulum, detachment of its RNA granules, etc. They are more prominent in sensitive strains (Yoshida sarcoma AH-130) than in the resistant strain AH-7974. The changes described are commonly encountered in photomicrographs taken 6, 12, and 24 hours after the administration of Nitromin. Figures suggesting regeneration of mitochondria and of intake of protein or other substances were described. The mode of action of Nitromin was also discussed.

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Friend virus activity in the crude extract of enlarged spleen of mice with Friend disease is inactivated by its incubation with venom of Naja naja. Boiled venom having phospholipase A as a sole functional enzyme had potency to inactivate the agents. Deoxyribonuclease, ribonuclease, protease, and phosphodiesterase were ruled out as the active principle in the snake venom for inactivation of the virus. It was concluded that phospholipase A is responsible for this inactivation and therefore this virus would contain phospholipids.

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Previous findings had shown that the effect of anticancer agents in restoring lowered enzyme activities in the liver and especially that of catalase was not always in parallel with their therapeutic effect. To elucidate this, the possible inhibitory effect of these agents on heme metabolism, with special reference to iron, copper, and δ-aminolevulinic acid metabolism in normal and tumor-bearing mice, was investigated.
The δ-aminolevulinic acid dehydrase activity in the liver of tumor-bearers was lower than that of normal animals and was found to be very low in tumor cells. Of the anticancer agents tested in vitro, 2, 5-bis(ethyleneimino)-1, 4-benzoquinone and folic acid antagonists were found to inhibit this enzyme activity in normal mice.
On the other hand, carboxamide utilization in which δ-aminolevulinic acid is concerned with the source of a C₁-donor occurred at a much higher rate in tumor cells than in the liver of normal and tumor-bearing mice. In the presence of folic acid antagonists, and d-catechin and berberine, carboxamide utilization by tumor cells was markedly inhibited in vitro.
Daily decrease in the serum iron level, blood hemoglobin content, and liver δ-aminolevulinic acid dehydrase activity was observed after tumor transplantation, when the serum copper level increased. Administration of alkylating agents and 8-azaguanine to tumor-bearers restored these metabolic disturbances to normal in parallel with their therapeutic effects. These agents showed no influence on these levels in normal mice. 6-Mercaptopurine, which has a marked anticancer activity with Ehrlich ascites carcinoma, returned the lowered liver δ-aminolevulinic acid dehydrase activity and elevated serum copper level in tumor-bearing animals to normal. However, the lowered serum iron level and blood hemoglobin content in tumor-bearers were further depressed by treatment with 6-mercaptopurine and this depressive action was also found in normal mice. Treatment with aminopterin, which was not effective against Ehrlich ascites carcinoma at the dose level tested, did not restore the altered metabolism of tumor-bearing animals to normal and this agent caused a depression of the blood hemoglobin content in normal mice.
The significance of these results in relation to those in the previous report is discussed.

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The condition specified by the term cachexia in tumor-bearing animals may be considered as due to the disturbance of normal balance between the metabolic pathways. It is a matter of great interest in the study of the host-tumor relationship to investigate how the metabolic balance may be disturbed in tumor-bearing animals. In this respect the inducible formation of the enzyme seems to be of great importance as one of the factors controlling the metabolic balance.

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This study deals with the comparison of karyotypes in ascites tumor cells with those in the metastatic ones in MH-134 mouse hepatoma. This tumor was characterized by bimodal distribution of chromosome numbers with modes at 40 and 80 in its ascites tumor cell population. The karyotypes in the former group were characterized by 38 telocentrics and 2 metacentrics, and those of the latter consisted of 76 telocentrics and 4 metacentrics. The frequency of these two karyotypes was almost the same in the lymph nodes and metastasized organ tumors, as well as in the ascites tumor.

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Repeated intraperitoneal injections of thalidomide (1000mg/kg/day) had a moderate inhibitory effect on Lewis bladder carcinoma. However, thalidomide had practically no inhibitory effect on the growth of 24 other mouse, rat, and hamster tumors.

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1) Population growth in female NA₂ mouse of MN ascites sarcoma T strain was studied by direct cell-count.
2) The initial latent phase, even if it exists, was shorter than 24 hours in duration.
3) Cell population continued to increase for longer period with inoculation of a smaller number of cells and approached a maximum which was nearly equal in magnitude to that attained by the inoculation of larger number of cells.
4) The increase of population showed deviation from logarithmic growth; cube root of cell numbers plotted against time gave rise to nearly straight line.
5) Whether or not changes of inoculum size is accompanied by a shift of the growth pattern remained to be determined.

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A basic protein fraction having toxohormone activities, isolated from Rhodamine sarcoma, was subjected to carboxymethylcellulose column chromatography. The fractions of effluent were analyzed by copper-Folin reaction and each peak was tested for toxohormone activity such as depressing effect on plasma iron, liver catalase, and tryptophan pyrrolase. Under these experimental conditions, the high activity of depressing plasma iron and smaller catalase, and tryptophan pyrrolase-depressing activities were found in the fast-moving fractions separated from the fraction which combined strongly with cellulose and had these three kinds of toxohormone activity. From this result, there is the possibility that the plasma iron-depressing factor is associated with different chemical entities from other toxohormone factors of the basic protein.

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Subcutaneous solid tumor induced by Kasuga and Oota from leukemic tissues of Friend virus-infected ddOM mica, was transformed into ascites tumor form and has been successively transplanted in an ascitic form to 30th generation. This tumor has been tentatively designated as Friend virus ascites sarcoma. It is 100% transplantable in ddOM mice but approximately 80% in ddY or ddN mice. The tumor, composed of mononuclear cells resembling immature reticulum cells, is considered to have originated from reticulum cells. Virus content in both tumor tissues and tumor ascites was found to be much smaller than that in spleens by both titration and electron microscopic studies. It is still obscure whether a generalized Friend virus-induced leukemia always following transplantation of tumor ascites is due to tumor cells themselves or not.

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Newborn mice of high-leukemia strains, AKR and SL, were given injection of a relatively low dose of 20-methylcholanthrene at birth. Neither enhancement of leukemia development nor induction of other tumors was noted in the AKR strain. In the SL strain, inhibition of leukemogenesis and frequent development of pulmonary adenoma and subcutaneous sarcoma were observed.

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