Noncoding RNAs as Novel Biomarkers in Prostate Cancer

Figure 1

The human genome consists of approximately 2% protein-coding sequences, which can be transcribed into messenger RNAs (mRNAs) and then translated into proteins. The majority of the human genome exists in nonprotein-coding DNA, which can be transcribed in (functional) noncoding RNAs (ncRNAs). According to their size and function, ncRNAs can be grouped into long noncoding RNAs (lncRNAs) and small ncRNAs. The group of small ncRNAs, which are less than 200 nucleotides (nt) in length, consists of microRNAs (miRNAs), piwi-interacting RNAs (piRNAs), ribosomal RNAs (rRNAs), small Cajal body-specific RNAs (scaRNAs), small-interfering RNAs (siRNAs), small nuclear RNAs (snRNAs), small nucleolar RNAs (snoRNAs), and transfer RNAs (tRNAs). Beside their biogenesis from hairpin precursor molecules, miRNAs can also be derived from lncRNAs and snoRNAs (highlighted in red).