Serum miR-181а and miR-25 Levels in Patients with Breast Cancer or Benign Breast Disease.

Circulating miR-181а and miR-25, which reflect regulation of the expression of carcinogenesis-related genes, were assayed in patients with invasive carcinoma of no specific type (ICNT) or benign breast diseases (BBDs) and in subjects without pathologies of the mammary gland (controls). miR-181а expression level proved to be higher compared to control in patients with fibroadenoma and adenosis with low, but not high, risk of malignant transformation, as well as in patients with luminal HER2-negative type B (Lum B HER2-), HER2-positive type (HER2+), and triple-negative breast cancer (TNBC) than in the controls and luminal-type (Lum A) breast cancer. MiR-25 expression level prevailed in patients with Lum B HER2- compared to control, Lum A, and TNBC patients compared to Lum A. Thus, miR-181а and miR-25 expression levels may be risk indicators of malignant transformation in some patients with BBD, whereas in patients with ICNT, these levels reflect pathological processes of different directions within the tumor.