Genomic and Transcriptomic Landscape of Triple-Negative Breast Cancers: Subtypes and Treatment Strategies.

Summary We comprehensively analyzed clinical, genomic, and transcriptomic data of a cohort of 465 primary triple-negative breast cancer (TNBC). PIK3CA mutations and copy-number gains of chromosome 22q11 were more frequent in our Chinese cohort than in The Cancer Genome Atlas. We classified TNBCs into four transcriptome-based subtypes: (1) luminal androgen receptor (LAR), (2) immunomodulatory, (3) basal-like immune-suppressed, and (4) mesenchymal-like. Putative therapeutic targets or biomarkers were identified among each subtype. Importantly, the LAR subtype showed more ERBB2 somatic mutations, infrequent mutational signature 3 and frequent CDKN2A loss. The comprehensive profile of TNBCs provided here will serve as a reference to further advance the understanding and precision treatment of TNBC. Graphical Abstract Highlights • We build the genomic and transcriptomic landscape of 465 primary TNBCs • Chinese TNBC cases demonstrate more PIK3CA mutations and LAR subtype • Transcriptomic data classify TNBCs into four subtypes • Multi-omics profiling identifies potential targets within specific TNBC subtypes Jiang et al. characterize primary Chinese triple-negative breast cancer (TNBC) and classify it into four subtypes. They find that these TNBCs have more frequent PIK3CA mutations and chromosome 22q11 copy-number gains than non-Asian TNBCs and that the LAR subtype has more ERBB2 somatic mutations and CDKN2A loss. [ABSTRACT FROM AUTHOR]