lncRNAs and Breast Cancer Development

Abstract

Breast cancers are highly heterogenous between and within tumors. Genomic instability is postulated to contribute to this process, also facilitating a high degree of plasticity, as the capability to adapt and survive in hostile microenvironments. Mechanisms leading to genomic instability include microsatellite and chromosomal instability, which by contrast participate respectively to the acquisition of point mutations and accumulations of chromosomal aberrations. While models of cancer evolution have been postulated, the increasing evidence that lncRNAs can have a causative role in cancer raises the question regarding the relevance and the biological consequences of the mutations in noncoding genes and regions at the different stages of the process of tumorigeneses. Though metastasis occurrence represents the overwhelming cause of mortality in breast cancer patients, the molecular mechanisms that drive tumor cells to acquire metastatic traits are still largely unknown. In this respect, the identification of metastatic mediators would be of certain prognostic and therapeutic benefit. Dysregulation of lncRNA expression has been found to contribute to breast cancer metastatic progression through aberrant regulation of tumor-suppressive or oncogenic pathways. The great majority of lncRNAs implicated in the metastatic process act as oncogenic factors