A molecular portrait of microsatellite instability across multiple cancers


Cortes-Ciriano I*, Lee S*, Park W-Y, Kim T-M**, Park PJ**. A molecular portrait of microsatellite instability across multiple cancers. Nat Commun 2017;8:15180. Copy at http://www.tinyurl.com/y4eh9sfz

Date Published:

2017 Jun 06


Microsatellite instability (MSI) refers to the hypermutability of short repetitive sequences in the genome caused by impaired DNA mismatch repair. Although MSI has been studied for decades, large amounts of sequencing data now available allows us to examine the molecular fingerprints of MSI in greater detail. Here, we analyse ∼8,000 exomes and ∼1,000 whole genomes of cancer patients across 23 cancer types. Our analysis reveals that the frequency of MSI events is highly variable within and across tumour types. We also identify genes in DNA repair and oncogenic pathways recurrently subject to MSI and uncover non-coding loci that frequently display MSI. Finally, we propose a highly accurate exome-based predictive model for the MSI phenotype. These results advance our understanding of the genomic drivers and consequences of MSI, and our comprehensive catalogue of tumour-type-specific MSI loci will enable panel-based MSI testing to identify patients who are likely to benefit from immunotherapy.

Last updated on 12/24/2017