Next generation sequencing (NGS) in oncology: lights and shadows

Abstract

Advances in tumor genome sequencing using next generation sequencing (NGS) technologies have facilitated a greater understanding of the genetic abnormalities involved in cancer development and progression, dramatically changing oncology research. There are several different types of NGS technologies. Whole genome sequencing (WGS) determines the sequence of the complete genome, providing information on both coding and non-coding regions and structural variants. However, use is limited by the large volume of data generated, and associated time and resource costs. Whole exome sequencing (WES) determines the sequence of coding regions only, making it faster and cheaper than WGS, and the functional consequences of variants are easier to interpret. However, all variations in non-coding regions are missed. WGS and WES are often used together to maximize detection of variants. A less costly approach is the use of targeted sequencing, which focuses on particular regions of interest, based on their biological relevance. NGS technologies can also be used to sequence RNA, referred to as RNA-Seq. All these NGS technologies, individually or in combination, have a number of potential applications, including identification of biomarkers, and development of diagnostic and therapeutic strategies. However, although advances have been made, there are a number of limitations to be overcome before NGS technologies are routinely applied in both research and clinical practice.