Experimentally produced synovial sarcoma in mice.

BALB/c and C57 B1/6 mice which received weekly subcutaneous injections of a cannabinoid developed tumors at the points of injection. In the groin the tumors were fibrosarcomas, while in the interscapular region they were anaplastic sarcomas and synovial sarcomas. The latter developed faster and were larger in cannabinol - and cannabidiol-treated C57 B1/6 mice than in delta 9-tetrahydrocannabinol-treated BALB/c mice. This difference could not be attributed to strain differences. 2 cannabidiol- and 1 cannabinol-treated C57 B1/6 females with the fastest growing synovial sarcomas were pregnant and, in addition, 2 of them developed mammary adenocarcinomas, indicating that they were rich in estrogen. On the other hand, it is known that delta 9-tetrahydrocannabinol causes a decrease in the sex hormone. It is consequently thought that the cannabinoids are only initiators of synovial sarcoma, while growth or promotion of the latter is influenced partially or entirely by the sex hormone.

Gastro-intestinal tumors in mice of three strains maintained on fat-enriched diets.

Mice of three strains were used in the present experiments. The control mice (group 1, 7 and 9) have been kept on Purina chow only. For the experimental mice of the T.M. strain the Purina chow was supplemented with refined corn oil (group 2), crude corn oil (group 3), regined corn oil plus free fatty acids (group 4), Monoolein (group 5) and Monostearin (group 6). For the experimental mice of the BALB/c and C57 Br. strains (group 8 and 10) Purina chow was supplemented with raw egg yolk. Very few of the control mice developed tumors of the forestomach (3/195 mice in group 1 and 1/165 mice in group 9) and none of them developed pyloric or intestinal tumors. Among the mice maintained on the fat-enriched diets the incidence of tumors of the forestomach and of the pyloric glandular part of the viscus was relatively high, except for the mice in group 6, maintained on Purina chow supplemented with monostearin. Intestinal tumors were found only in mice of the BALB/c and C57 Br. strains maintained on Purina chow supplemented with egg yolk. The tumors were for the most part polyps, except for adenocarcinomas developed by three C57 Br. mice from group 10. The difference between mice of the T.M. strain, (which did not develop intestinal tumors), and those of the BALB/c and C57 Br. strains, (which developed intestinal tumors), may be due to a difference in their susceptibility or to the difference in their diets.

Primary and secondary heart tumors in mice maintained on various diets.

Two mice of the TM strain, maintained on Purina chow supplemented with refined coin oil plus free fatty acids, in one case, and with refined corn oil without free fatty acids, in the other case, developed primary heart rhabdomyosarcomas. The tumors metastasized to the lungs and the kidney, in the first case, and to the lungs alone in the second case. One mouse of the TM strain, on the diet supplemented with corn oil plus free fatty acids, developed a fibrosarcoma behind the right anterior extremity. Metastases from the tumor were found in the liver, lungs and myocardium. Another mouse of the C57 Bl. strain, injected subcutaneously, in the interscapular region, at the age of 7 days, with a single dose of 30 mug of Delestrogen, developed, at the point of injection, a large rhabdomyosarcoma. At the age of 5333 days, when the animal was killed, metastases from the tumor were found in the intercostal muscles and in the heart. Three mice, one of the TM strain, on a diet supplemented with corn oil and cholesterol, and two of the C57 Br. strain, on a diet supplemented with raw egg yolk (rich in cholesterol) had organized blood clots in the atria (in two mice) and one extending into the ventricle.