The Association of Genomic Lesions and PD-1/PD-L1 Expression in Resected Triple Negative Breast Cancers

We used DNA content-based flow cytometry to distinguish and isolate nuclei of clonal tumor populations from resected triple negative breast cancer tissues. We then interrogated each sorted tumor population with whole genome aCGH and next generation sequencing (NGS). The genomic data was correlated with IHC staining for PD-1 and PD-L1. We applied DNA content based flow sorting to isolate the nuclei of clonal populations from tumor biopsies obtained from resected TNBCs. We coupled this strategy with oligonucleotide array CGH (aCGH) and next generation resequencing, thereby obtaining high definition genomic profiles of clonal populations from each tumor. These data were then correlated with the presence or absence of PD-1 and PD-L1 expression as measured by IHC.