Involvement of lncRNA in cancer diagnosis and prognosis and clinical implications

Long non-coding ribonucleic acids (lncRNAs) form a subclass of non-coding RNAs (ncRNAs), they are quite long and as their name non-coding suggests they do not have a role in protein coding. lncRNAs are vital in all the key steps of tumorigenesis, such as epithelial-mesenchymal transition, cancer stem cells formation, invasion, migration, and formation of the tumor vasculature. lncRNAs are classified into oncogenic or anti-tumor lncRNAs based on their functions. Moreover, cancer stem cells show an extremely specific pattern of expression of lncRNAs, which can be used for early detection of cancer. Similarly, their pre-treatment expression levels correlate with prognosis as they participate in key tumor biology processes like metastasis and recurrence. This chapter seeks to explore both the association between lncRNA genes and cancer and the role of lncRNAs in cancer initiation and progression. Future questions would focus on what the accepted normal ranges of lncRNA expression will be, where they are present in body fluids, which could help with non-invasive tests. But for now, one thing is clear that lncRNAs could pave the way for novel cancer therapies.