miR-205 in Breast Cancer: State of the Art

Despite its controversial roles in different cancer types, miR-205 has been mainly described as an oncosuppressive microRNA (miRNA), with some contrasting results, in breast cancer. The role of miR-205 in the occurrence or progression of breast cancer has been extensively studied since the first evidence of its aberrant expression in tumor tissues versus normal counterparts. To date, it is known that the expression of miR-205 in the different subtypes of breast cancer is decreasing from the less aggressive subtype, estrogen receptor/progesterone receptor positive breast cancer, to the more aggressive, triple negative breast cancer, influencing metastasis capability, response to therapy and patient survival. In this review, we summarize the most important discoveries that have highlighted the functional role of this miRNA in breast cancer initiation and progression, in stemness maintenance, in the tumor microenvironment, its potential role as a biomarker and its relevance in normal breast physiology-the still open questions. Finally, emerging evidence reveals the role of some lncRNAs in breast cancer progression as sponges of miR-205. Here, we also reviewed the studies in this field.

Automated summary

Despite controversial roles in different cancer types, miR-205 is mainly described as an oncosuppressive miRNA in breast cancer. Its expression decreases from less aggressive to more aggressive subtypes and influences metastasis capability, therapy response, and patient survival. MiR-205 plays a role in breast cancer initiation and progression, stemness maintenance, tumor microenvironment, and may serve as a biomarker with relevance in normal breast physiology. Additionally, some lncRNAs are implicated in breast cancer progression by acting as sponges of miR-205.