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Previous findings show that experimental tumors of the mouse, such as Ehrlich carcinoma and Sarcoma 180, transplanted in different sites, elicit a different sensitivity to the same drug according to the site of tumor implantation. Cyclophosphamide is highly active on intraperitoneal or subcutaneous tumors, but is ineffective on intracerebral tumors. However, the opposite is true for drugs such as nitroso-derivatives, which are active only on intracerebral tumors. The studies presented in this report were performed in order to elucidate whether different concentrations of drugs at the three tumor sites are related to the different antitumoral effects. It was found that measurements of blood and tissue concentrations explain fairly well the different activities of the drugs being tested.

SummaryTwo experiments were conducted using rats of the Marshall 520 strain depleted in vit. B6 by the use of a deficient diet and 4-desoxypyridoxine. Osteogenic Sarcoma 344 was transplanted into the deficient animals, a pair-fed group and an ad libitum group. Desoxypyridoxine was removed from the diet of the deficient animals on the day of tumor transplant. In Exp. 1 daily measurements of the tumor showed a marked inhibition of the growth of the tumor in the deficient animals as compared to the control groups. The mean weight of the tumor and also the mean weight as a percentage of final mean total body weight were also decreased. In a second experiment larger, more mature animals were used. Tumor inhibition in the deficient animals was again observed, although it was not so striking as in the first experiment. No histological differences in the tumor were noted in either experiment with the exception of increased hemorrhage and necrosis in the neoplasms of the ad libitum animals.

An actinomycete, isolated from soil, was selected for investigation on the basis of its ability to produce an agent inhibiting WALKER 256 tumors in rats. This agent is a new antibiotic that has been designated "kundrymycin". Increased kundrymycin yield was obtained with media development and strain selection. Improvement was based on results obtained in in vivo tumor inhibition tests. Antibiotic yield in an 800-gallon (3, 000-liter) tank fermentation was 4.2mg/ml.

In recent years, there has been much research on the applications of ultrasonic techniques to medicine. This paper discusses some of the projects being carried out in the fields of diagnosis, therapy, dentistry, and bacteriology. The diagnostic investigations presented include brain tumor detection, soft tissue visualization, and analysis of cancers for malignancy. The therapy studies include tissue diathermy, brain surgery, and tumor inhibition. Drilling of teeth is the application discussed in dentistry. In all cases, an attempt is made to elucidate the mechanisms pertinent to the applications.

Investigation of the cytotoxic principles of Annona purpurea L. resulted in the isolation and characterization of four new alkaloids of the aporphine variety. One of the four is an oxoaporphine which shows borderline activity in vitro against the 9-KB tumor test system. The known aporphine isocorydine, oxoaporphine O-methylatheroline, and the proaporphines glaziovine and stepharine were also obtained. Glaziovine and O-methylatheroline also showed limited tumor inhibition.

SummaryImmature AKD2F1 mice were examined for possible estrogenic inhibition of Sarcoma 1. Large doses of estradiol benzoate inhibited growth of tumor in intact animals and in hysterectomized castrates. It was concluded that this estrogenic effect can be achieved in absence of uterus, and that the tumor-inhibitory properties of endometrial secretions act by a mechanism different from that of estrogen.

The chemotherapeutic action of Bleomycin, applied at a dosage which induced only a non-specific tumor inhibition on HRS-sarcoma, was potentiated by combination with inosine. This combination, without increasing toxicity, effected both a significant tumor inhibition and a significant curative action.

In order to determine the type of relationship which exists between gluconeogenesis inhibition at the phosphoenolpyruvate carboxykinase (PEP CK) reaction and tumor inhibition, the tumor-inhibiting eff

Studies with several chemically-induced animal tumors have demonstrated that implantation of tumor cells in admixture with viable Bacillus Calmette-Guerin (BCG) prevents their growth in genetically compatible hosts [1, 3, 5]. Deliberate infection of established local tumors may also lead to their suppression [1, 7] and the inhibition of metastases [7]. The mechanism of this tumor inhibition is not yet understood, although factors other than immunostimulation are involved, since intimate contact between BCG organisms and tumor cells is necessary [1, 5] and may contribute to this effect.

In the fall of 1958, the senior author working in the laboratory of Dr. Ayao Yamamoto, Institute for Infectious Diseases, University of Tokyo, cooperated with Drs. Yamamoto, Ogata, Komatsu and Nakazama in studying the effect of saline extracts of Lampteromyces japonica (L.J.) on Ehrlich mouse tumors and Sarcoma 180. This work included in vivo and in vitro studies with findings of some anti-tumor activity. Lucas et al.(1,2) have demonstrated tumor inhibition by extracts of the fungus genus Calvatia and Holobasidiomycetes.It seemed desirable to extend these preliminary observations and to determine the effect of fractions of L.J. on the Ehrlich mouse tumor and on human tumor cells growing in tissue culture.Materials and methods. The tumor-inhibiting original extract was prepared from dried Lampteromyces japonica, the only species of this basidiomycete. The original samples were collected in Japan in 1959.Ten g of dried material, ground in a 20-mesh Wiley Mill, were extracted with 100 ml of saline (0.85% NaC...

The sum total of inhibition of growth capacities of spontaneous tumors in mice obtained with three nucleosides used separately is similar to, if not identical, with the amount of inhibition obtained by the use of the original liver emulsion. There is also clear evidence that most of this tumor inhibition is brought about by 5 methyl cytidine (0.02 molar concentration administered intraperitoneally three times weekly with a maximum injection of a volume of 0.05 cc). Adenosine is not only an inhibitor of cancer in mice but, under certain conditions, also a stimulator (0.05 molar percentage solution with maximal injections at any one time of 0.05 cc volume). This conversion of an inhibitor of cancer to a stimulator has been brought about by aging of the solution but how the conversion takes place is not known. However, this conversion of the effect of adenosine was obtained by the same procedure that the inhibitor of cancer in the liver emulsion can be converted to a stimulator of cancer.

Two hundred and sixty-three control mice of the C3 H/ST inbreds bearing spontaneous tumors of mammary gland origin have been studied in reference to the injection of a specially prepared liver extract into one or more of their ancestors. Of these, 24 mice were from the original inbred strain in which no liver extract had ever been injected. Two hundred and thirty-nine mice were among the descendants of a mouse that had received an intraperitoneal injection of a liver emulsion. These 239 mice were spread over 15 generations of lineal descent. All mice (263) of this experiment were kept as “controls” when their spontaneous tumors arose. The evidence obtained with the analysis of the growth rate of these tumors indicated the activity of a “transmissible entity” which increased in potency in suppressing these cancerous growths. The new evidence, obtained after six generations of lineal descent separation from the original injection of the liver extract, demonstrated quite convincingly that the amount of tumor inhibition became erratic and finally disappeared. The value of growth rate of tumors in mice of the 15th generation returned to the original rate obtained in mice of the 0 class in which there had been no treatment with liver extract in their ancestry.

Summary1. The per cent tumor inhibition, change in carcass weight, and concentration of nonprotein methionine in the liver, resulting from administration of ethionine to normal, castrated, and testosterone-treated castrated male rats, has been determined. 2. Tumor inhibition by ethionine, and the toxi-city of this substance, was greater in castrated than in normal or testosterone-treated castrated male rats and closely resembled that observed in female rats. 3. The concentration of free nonprotein methionine in the liver of castrated male rats was similar to that found in female rats and differed from that observed in normal male or testosterone-treated castrated male rats. The presence of a methionine conjugate was indicated in the liver of castrated male and normal female rats following ethionine administration while such a conjugate was lacking in the liver of normal male or testosterone-treated castrated male rats. 4. It was concluded that the sex difference observed in tumor inhibition, toxicity, and...

dl-C-allylglycine inhibited the growth of Rd/3 sarcoma in male rats. The percentage tumor inhibition ranged from about 10–50 in a series of experiments carried out during an 18 month period.