DNA barcoding reveals ongoing immunoediting of clonal cancer populations during metastatic progression and in response to immunotherapy [WGS of target clones]

By using DNA barcoding to trace individual cancer cells from the 4T1 murine model of cancer, we were able to identify two cancer cell clones that were highly immune evasive and resistant to immune destruction both by the endogenous immune system and when treating with immunotherapy. We isolated these clones (IE1 and IE2) from the bulk parental population for further characterisation. We wondered if copy number variations could explain the phenotype we observed, so we carried out WGS to investigate this. We carried out whole genome sequencing on one replicate per derived cell line (IE1, IE2, NT1 and NT2) at 30x sequencing depth.