STUDY OF THE EFFECT OF LOMUSTIN ON HER2-POSITIVE BREAST CANCER IN FVB/N HER-2 TRANSGENIC MICE

• Main Authors: A. N. Stukov, S. F. Vershinina, N. A. Koziavin, T. Yu. Semiglazova, L. V. Filatova, D. Kh. Latipova, A. O. Ivantsov, V. G. Bespalov, A. L. Semenov, O. A. Belyaeva, G. S. Kireeva, V. A. Alexandrov, G. V. Tochilnikov, I. N. Vasilyeva, M. A. Maydin, M. L. Tyndyk, S. S. Kruglov, G. A. Yanus, V. N. Yurova
• Format: Article
• Language: Russian
• Published: Tomsk National Research Medical Center of the Russian Academy of Sciences 2019-11-01
• Series: Sibirskij Onkologičeskij Žurnal
• Subjects: her2-positive breast cancer; her2 transgenic fvb/n mice; lomustine; intracranial tumor; tumor growth index
• Online Access: https://www.siboncoj.ru/jour/article/view/1188
• ISSN: 1814-4861; 2312-3168

Because of the high risk of brain metastases from HER2-positive breast cancer, the study of the anticancer activity of drugs used to treat brain tumors, in particular lomustine, is of great importance. In the FVB/N Her-2 transgenic mice bearing HER2-positive breast cancer (BC HER2+), a single oral administration of lomustine at a dose of 50 mg/kg resulted in a significant tumor growth inhibition (up to 96 %, p<0.0001). The tumor growth index (TGI) expressed as a ratio between the areas under the kinetic curves of tumor growth in the study and control groups and amounted to 33 % (p<0.001) indicated the high activity of lomustine. However, the effect of lomustine on intramuscularly transplanted Ehrlich tumor was insignificant (tumor growth inhibition and tumor growth index were <39 % and 68 %, respectively). Lomustine administered orally at a single dose of 50 mg/kg 24 hours after intracranial transplantation of BC HER2+ increased the median survival time up to 30 days in FVB/N mice compared to 21 days in the control group mice (p<0.001). The high therapeutic effect of lomustine in HER2-positive breast cancer mice is likely can be explained by the biological characteristics of this tumor; therefore clinical trials of lomustine for HER2-positive tumors are needed.