MicroRNA in Lymph in Experimental Breast Cancer

Abstract

Breast cancer (BC) is the leading cause of cancer death in women worldwide due to the complicated etiology involving both genetic and environmental factors. Objective: To study the expression levels of miRNAs (-21, -221, -222, -429) in lymph in Wistar female rats in chemically induced breast cancer, resection and chemotherapy of breast cancer. Methods-The histological type of BC, the phenotype of BC cells, the level of mIRNAs expression in lymph was studied. Results-MNU-induced breast cancer in animal has ER-/PG+/Her2/neu- phenotype and therefore has common feature with human luminal A subtype of breast cancer. In the breast cancer group, lymphomas significantly increased the levels of miRNA-21 and miRNA-221 expression compared to the control group. After chemotherapy, the expression levels of miRNA-21 and miRNA-221 were significantly reduced compared to the BC group. In the BC group, the expression levels of miRNA-429 are significantly reduced compared to the control group. After chemotherapy, the expression of miRNA-429 is significantly increased in comparison with the BC group. Conclusion-In lymph miRNA-21 and miRNA-221 are diagnostic-relevant tumor markers. MicroRNA-429 is diagnostic-relevant marker of the chemotherapy effectiveness.