Pulmonary Tumors in Mice

Publisher Website
Google Scholar
Abstract
VI. Evidence is presented that small amts. of l:2:5:6-dibenzanthracene or methylcholanthrene induce pulmonary tumors in strain A mice which are highly susceptible to the development of spontaneous pulmonary tumors. The possible factors involved in the occurrence of induced lung tumors in mice are discussed, i.e., whether the tumors are caused by the direct action of the hydrocarbons upon lung tissues or whether they arise because the chemicals release an hereditary tendency. Other factors which may play contributory roles in the appearance of the tumors are also discussed. VII. 20 pulmonary tumors arising in inbred mice were used in this investigation. 5 tumors arose spontaneously in strain A mice while 6 were induced in strain A mice, 6 were induced in strain C mice and 2 were induced in mice of strain C3H by parenteral inj. of l:2:5:6-dibenzanthracene. One tumor found in a strain A mouse could not be classified definitely as spontaneous or induced. The tumors underwent 2 to 49 serial passages in the subcut. tissues of normal mice of the strain in which they originated. Histologic examination revealed that 18 of the primary lung tumors were of an adenomatous structure. During animal passages 6 tumors retained the histologic structure of the original tumor, 7 lost the structure of the original tumor to a considerable extent, while 5 changed into spindle cell tumors. Of the 5 tumors which became spindle cell in appearance, 1 arose spontaneously in a strain A mouse, 2 were induced in strain A mice, 1 was induced in a strain C mouse, and one was induced in a strain C3H mouse. Both spontaneous and induced tumors exhibited the phenomenon and the change was not limited to pulmonary tumors occurring in any particular strain of mice. The investigation did not offer any explanation for the pronounced change in histologic structure of some lung tumors during serial passages in the subcut. tissues of normal mice. VIII. Intravenous or subcut. adm. of 0.6 to 1.0 mg. 1,2,5,6-dibenzanthracene induced primary pulmonary tumors in mice of strains D, M, C57 brown, and C57 black, and hybrids derived from the D and C57 black strains. These strains were highly resistant to the development of spontaneous pulmonary tumors. IX. The subcut. inj. of 30 to 110 mg. 2-amino-5-azotoluene induced primary pulmonary tumors in 18 out of 24 strain A mice, and in 12 out of 14 strain C mice, within 3 to 12 mos. The subcut. inj. of 0.2 mg. 3,4,5,6-dibenzcarbazole induced primary pulmonary tumors in 15 out of 19 strain A mice within 4.2 mos.

This publication has 1 reference indexed in Scilit: