Preparation of biologically active cell-free extract (CFE), as well as its acetone powder (EAP) has been achieved by grinding hemolytic streptococci with alumina under the controlled conditions of temperature and others. Both samples, CFE and EAP, were employed for streptolysin-S-synthetizing and anticancer studies, the results of which were as follows:
1) When placed a mixture of EAP (as well as CFE) and yeast RNA at 37°C for 2 hours, appreciable amounts of streptolysin-S were produced.
2) Incubation of a mixture of EAP and Ehrlich ascites carcinoma cells at 37°C for 1.5 hours caused a complete loss of invasion power of the carcinoma cells to mice.
3) Treating at 56°C for 30 minutes resulted in a complete inactivation of the samples.

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The correlation between the structural change of RC4 and the variation in the anti-glycolytic activity was examined by quantitative analytical method such as colorimetry or titration, and the following results were obtained.
The antiglycolytic activity of RC4 is intensified with the cleavage of its ethyleneimino rings. It is presumed that polymerization between the aminoethanol moiety, which has been formed by the ring cleavage, and the intact ethyleneimino ring increases the activity. Whereas it was inferred in the previous report that the rate of the activity variation of RC4 is determined by a higher order reaction, the above mentioned polymerization reaction seems to correspond to this.
It is also presumed that the revelation of the anti-glycolytic activity of o-RC4 or TEPA is also influenced by the cleavage of the ethyleneimino ring.

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Our preliminary studies on the use of pulmonary tumor formation by intravenous injections of cancer cells for chemotherapeutic tests have been extended. With Ehrlich ascites carcinoma the standard dose for a predictable positive tumor formation was established to be about one million cells, and by detailed histological examination of the lung at various intervals after the intravenous inoculation, the events leading to the formation of pulmonary tumors were demonstrated to resemble very closely those of the natural tumor metastasis formation.
Intravenous injections of several known anti-cancer chemotherapeutics, however, failed to markedly inhibit the formation of these "artificial lung metastases", at least in the dosages tested by us, which indicated that the suppression of intrapulmonary growth of blood-borne cancer cells may be far more difficult than that of intraperitoneal or subcutaneous cancer transplants.

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The present paper deals with the cytological effects of 8-azaguanine and related compounds on the chromosomes of Yoshida sarcoma cells. 8-Azaguanine effected a deformation of chromosomes into round ones and an increase of mitotic rate by arresting mitosis at metaphase. As indicator of the effect of 8-azaguanine, the frequencies of the affected cells were observed after treatment with 8-azaguanine and 9 related compounds.
Generally speaking, compounds having two pyrimidine and triazole nuclei brought about the most powerful effects, while that of chemicals having pyrimidine and imidazole nuclei was shown to be considerable weaker. Compounds having pyrimidone and triazole nuclei or triazole nucleus alone effected only an increase of cells with round chromosomes. Chemicals with imidazole and pyrimidone nuclei did not affect either mitosis or the chromosomes of the tumor cells.

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The Yoshida sarcoma was transplanted to Buffalo rats in the author's laboratory. One of the rats developed a solid tumor in the peritoneal cavity in addition to an ascites tumor. The ascites tumor was characterized by a high percentage of tetraploid cells. They increased in number during a few transplant generations, but later gradually decreased.
The majority of tumor cells in the near-diploid group had 40 chromosomes, while most of cells in the near-tetraploid group had 80 chromosomes. An idiogram analysis of the two groups revealed that the chromosome constitution of tetraploid cells was the result of duplication of the chromosome set of the diploid tumor cells.
As the cause of the temporary proliferation of the tetraploid cells immunological selection is considered.

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A microspectrophotometric study of the DNA content was made in one specimen of normal tissue and in eight human uterine carcinoma tissues. The results are shown in Table 2.
The normal liver tissue contained cells with a basic mean DNA content at 33.1 to 33.5 arbitrary units, showing a certain but limited degree of variation from cell to cell. Malignant tissues showed a much larger scatter of DNA-value from cell to cell than occurred in normal tissues. Four out of eight uterine carcinomas showed a DNA value lying in a hyperdiploid range. Generally, the DNA value of uterine carcinomas here considered tends to correspond to the stemline chromosome-number in each.

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1. Quantitative measurements of some metals (Cu, Fe, Mo and Ni) were made in pupae of tumor and non-tumor strains (Oregon R, bw, v, st, tu, bw tu, v tu and tu st) of Drosophila melanogaster with the use of synthetic medium through the metal analysis with the acid-ashing treatment. Viability of flies and their melanotic tumor-incidence were also examined.
2. It is shown that tumor formation itself is related to "lethality" of flies and that the tryptophan metabolism in relation to brown pigment formation in the eye is associated with increasing viability through melanization.
3. From the results of metal analysis it is strongly suggested that Mo or Ni has an intimate relation to tumor formation itself in some way.

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1. Apparent molar extinction coefficient of the polar dye Fr. 2 was obtained as the result of experiment using radioactive polar dye derived from the nuclear labelled dimethylaminoazo-¹⁴C-benzene administered. A value of 32, 000±2, 000 as an apparent molar extinction coefficient for the polar dye Fr. 2 was obtained.
2. Using this value, the incorporation of N-¹⁴C-methyl carbon of M^*AB into the polar dye Fr. 2 was estimated quantitatively. The results showed that the N-methyl carbon (¹⁴C) of M^*AB is fully retained in the polar dye Fr. 2 without any serious loss during the binding with proteins in vivo.

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1. Apparent molar extinction coefficient of enzymically prepared polar dye Fr. 2 was obtained by measuring the concentration of the polar dye by estimating aniline liberated from the polar dye after the reduction and by measuring the extinction coefficient at 524mμ in 2N HCl-50% alcohol solution. A value of ca. 4.5×10⁴ was obtained for the polar dye Fr. 2. Almost the same value was obtained for the polar dye Sub-Fr. 2 enzymically prepared. The cause of the discrepancy in the apparent molar extinction coefficients of the polar dye obtained by two different methods, one by the aniline method described in this paper, and the other by the isotope method described in the previous paper, was discussed.
2. By means of paper chromatography under the condition described in the paper, polar dye Fr. 2 as well as Sub-Fr. 2 were further divided into at least two subcomponents having different Rf values, i.e. Rf 0.60 and Rf 0.74.
3. Rf 0.60 component seemed to be rather stable against the alkali treatment and showed a very sharp absorption spectrum in 2N HCl-50% alcohol solution, having a max. at 524mμ. Rf 0.74 component is rather unstable against the alkali treatment.
This showed two absorption maxima. in 2N HCl-50% alcohol solution, at 540mμ and at 500mμ, suggesting the presence of at least two subcomponents. The sub-component having 540mμ absorption max. seemed to be a hydroxylated derivative.

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1. By using P³², methylcholanthrene, benzpyrene and croton oil, osteogenic sarcoma was produced in albino rats and comments were made on its histogenesis.
2. Of the combined groups, especially the P³² and methylcholanthrene group and P³² and benzpyrene group showed high rate of production of osteogenic sarcoma. In other words methylcholanthrene and benzpyrene enhanced the carcinogenic action of P³², but croton oil did not promote the carcinogenic action of P³².
3. In 18 out of 30 cases tumors produced were osteogenic sarcomas, being over majority, and 7 cases were fibrosarcomas. Chrondrosarcoma was not seen.
4. In studying the process of development of immature osteogenic sarcoma cells into mature sarcoma cells, it was noted that the immature cells frequently arrange themselves in lobules or funiculi. The closely packed immature cells gradually hypertrophy and become more basophilic and atypical, and at the same time the intercellular spaces increase and hyaline substance is deposited. This substance finally becomes osteoid tissue and bone. With completion of ossification, the cells atrophy and some of them are embedded in the bone matrix.

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