Fig. 4

MHC Class I alterations in breast cancer ESR1 mutated patients. (A) Oncoprint of ESR1 Mutated tumors (33 h+/HER2- patients, 12 of which are ESR1 mutated). All mutations are missense. Overall, 20.4% of HR+/HER2- metastatic tumors harbor ESR1 mutation, uniquely missense (B) ViolinPlot of transcriptomic expression of MHC Class I (left) and MHC Class II (right). ESR1 mutated tumors have a significantly lower expression of every gene in those antigen-presentation mechanisms. C. Expression of ESR1 status in CD8 T cells and CD8 cytotoxic T cells. Blue: ESR1 Wild Type; Pink: ESR1 mutated. D. Number of unique TCR clones established that advanced ESR1-mutated BC (pink) had a lower number of TCR clonotypes detected compared to ESR1 wild type BC (blue). E. Antigen processing and presentation (KEGG) pathway regulation. Genes with lower expression in ESR1 mutated vs. ESR1 wild type IFNγ and TNFα; TAP1/2; the MHCI molecule and the class II molecule (HLA-DM) are depicted in blue