Dermatologica 157 (Suppl. 1): 52-53 (1978)
The Effect of Retinoic Acid on Lewis Lung Carcinom a M odel in M ice A Preliminary Note
K . L a pis , G . R ep Asy a n d K . K ir Al y | Departments of Pathology and Dermatology, Semmelweis Medical School, Budapest
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Based on the favorable effect of retinoic acid in dyskeratotic processes, its action on malignant tumors has been previously examined. Since several reports have shown its influence on human lung carcinoma, the trans plantable Lewis lung carcinoma model in mice was chosen for this investi gation. An inbred mouse strain (C 57 black) was used. 2 days following the inoculation of the tumor 20 animals were injected subcutaneously with 1 mg of all-tra«y-retinoic acid solution (33 mg/kg) daily for 10 days. 20 control ani mals were injected with the solvent. Retinoic acid given in this dosage occurred to be highly toxic; half of the treated animals succumbed. The sur viving animals were killed and the tumor growth and metastasis formation were compared. The growth of the transplanted tumor in the treated animals was signi ficantly retarded in comparison with the controls. The mean diameter of the tumor was 0.8 cm in the treated and 1.2 cm in the control group. Because of the early extermination of the animals, métastasés in the lungs could not be detected. Histologic examination showed the growth of the highly anaplastic tumor graft in the thigh among the muscle fibres. In microscopic preparations of the lungs, métastasés of different size could be seen around or in the lumen of bronchi of the control animals; in the treated group métastasés were either absent or their size was essentially smaller than that in controls.
The Effect of Retinoic Acid on Lewis Lung Carcinoma Model in Mice
53
Conclusions
The growth of the Lewis lung carcinoma tumor graft in mice treated systemically with all-fra/w-retinoic acid was slower than that in control animals. The number of metastases in the lungs was lower and their size was smaller in the treated group. Retinoic acid in the dose as used is toxic. It re mains to show whether the retardation of tumor growth is specific for the action of retinoic acid or if it is caused by the overall toxicity of the drug in a high dosage level.
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/8/2018 3:51:47 PM
Prof. Dr. K. L apis, Department of Pathology, Semmelweis University School of Medicine, 26, Ulldi Str., H-1085 Budapest (Hungary)
The Effect of Retinoic Acid on Lewis Lung Carcinom a M odel in M ice A Preliminary Note
K . L a pis , G . R ep Asy a n d K . K ir Al y | Departments of Pathology and Dermatology, Semmelweis Medical School, Budapest
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/8/2018 3:51:47 PM
Based on the favorable effect of retinoic acid in dyskeratotic processes, its action on malignant tumors has been previously examined. Since several reports have shown its influence on human lung carcinoma, the trans plantable Lewis lung carcinoma model in mice was chosen for this investi gation. An inbred mouse strain (C 57 black) was used. 2 days following the inoculation of the tumor 20 animals were injected subcutaneously with 1 mg of all-tra«y-retinoic acid solution (33 mg/kg) daily for 10 days. 20 control ani mals were injected with the solvent. Retinoic acid given in this dosage occurred to be highly toxic; half of the treated animals succumbed. The sur viving animals were killed and the tumor growth and metastasis formation were compared. The growth of the transplanted tumor in the treated animals was signi ficantly retarded in comparison with the controls. The mean diameter of the tumor was 0.8 cm in the treated and 1.2 cm in the control group. Because of the early extermination of the animals, métastasés in the lungs could not be detected. Histologic examination showed the growth of the highly anaplastic tumor graft in the thigh among the muscle fibres. In microscopic preparations of the lungs, métastasés of different size could be seen around or in the lumen of bronchi of the control animals; in the treated group métastasés were either absent or their size was essentially smaller than that in controls.
The Effect of Retinoic Acid on Lewis Lung Carcinoma Model in Mice
53
Conclusions
The growth of the Lewis lung carcinoma tumor graft in mice treated systemically with all-fra/w-retinoic acid was slower than that in control animals. The number of metastases in the lungs was lower and their size was smaller in the treated group. Retinoic acid in the dose as used is toxic. It re mains to show whether the retardation of tumor growth is specific for the action of retinoic acid or if it is caused by the overall toxicity of the drug in a high dosage level.
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/8/2018 3:51:47 PM
Prof. Dr. K. L apis, Department of Pathology, Semmelweis University School of Medicine, 26, Ulldi Str., H-1085 Budapest (Hungary)
