Expression of bovine leukemia virus antigen in breast cancer tissue

Breast cancer is a serious medical and social problem for most developed countries of the world. The search for new prognostic factors and targets for targeted therapy currently continues to be a pressing issue, as there are forms of breast cancer with uncertain targets for any type of therapy. The purpose of this work is to conduct an immunohistochemical study to detect and evaluate the expression of the antigen of the cow leukemia virus in the tissue of various types of breast cancer. Method. 100 cases of breast cancer were investigated, divided into subgroups, the studied parameters: steroid hormone receptors, HER2 / neu, VEGF, BLV expression, molecular genetic research on BRCA1/BRCA2 mutations. Results. In the group of triple negative breast cancer, 4 cases were detected expressing a cow leukosis virus antigen. Expression was represented by grains and clumps in the cytoplasm and on the surface of the tumor cell membrane, the wall of microvessels. Also in these cases, increased expression of VEGF was detected. Conclusion. The results indicate that expression of the BLV antigen was observed only in cases of poorly differentiated triple negative breast cancer. It is also noteworthy that the same type of BRCA1 gene mutation (5382insC) and increased expression of vascular endothelial growth factor were detected in these tumors. The authors first used the immunohistochemical method for detecting the antigen of the BLV virus, which made it possible to reliably confirm its presence in breast tumors with similar molecular genetic and immunohistochemical profiles.