Non-coding RNA as potential biomarkers for breast cancer functional diagnostics

Abstract

Previously it was believed that RNA mainly conveys the information encoded in DNA, so that other molecules, such as ribosomes, could use that code to create proteins. However, over the past 30 years, different types of RNA have been discovered. One of the most important of them is non-coding RNA (ncRNA) characterized by the absence of the open reading frame and not involved in the protein production. The discovery of numerous ncRNAs has revolutionized this field and changed the researchers’ ideas about physiology and development. Non-coding RNAs, sometimes called "dark matter" of the genome, constitute more than 90% of all RNAs encoded by the human genome. However, most of the known ncRNAs (~50,000) were discovered only during the last decade and remain understudied. Nevertheless since that time, it has been shown that many ncRNAs play an important role both in normal cell physiology and in diseases, including cancer. Thus, some small ncRNAs are so stable that they can exist in the bloodstream for a long time and can become a basis for an accurate and sensitive screening for major human cancers using only a few drops of blood or plasma. In addition, ncRNAs may become medications that could be delivered based on the same principle as the delivery of synthetic RNA and oligonucleotides targeting protein-coding mRNAs.

In this review, we addressed the role of some ncRNAs, miRNAs (siRNAs) and long ncRNAs (lncRNAs), in the pathogenesis of breast cancer. Much of this review will focus on ncRNAs as diagnostic biomarkers. We will also discuss their potential use in the personalized treatment of breast cancer.