In particular, the most differentially expressed miRNAs were validated by qRT-PCR, such that miR-200a-3p and miR-96-5p were up-regulated and miR-1-3p and miR-486-3p were down-regulated in patients with breast cancer with SLN metastasis.
Our results indicated that the overexpression of a miRNA (miR-1) could destroy mitochondria of cancer stem cells. miR-1 was downregulated in melanoma stem cells (MSCs) and breast cancer stem cells (BCSCs) compared with cancer non-stem cells.
These findings suggest that abnormal miR-1 expression is associated with an aggressive phenotype of breast carcinoma and that miR-1 status is a potent prognostic factor in human breast cancer patients.
Our further analysis detected substantial involvement of the miRNAs miR-324, miR-93, miR-615 and miR-1 in breast cancer, which was not known previously.
MicroRNA-206 (miR-206), as a homolog of miR-1, plays important roles in tumorigenesis and tumor progression of various human malignancies, including breast cancer, endometrial endometrioid carcinoma, rhabdomyosarcoma, glioma, lung cancer, and laryngeal cancer.