Non-synonymous mutations with a coverage above 500 reads and an allelic frequency above 3.0% were included into the analysis. Variants with an allelic frequency below 3.0% were filtered out and regarded as artifacts due to formalin fixation. Considering the percentage of tumor cells, the mutations validated needed to be detectable in at least 10% of the tumor sample.
The influence of mutations on proteasomal cleavage was predicted by the machine learning tool NetChop 3.1 [43 (link), 44 (link)]. The binding of the resulting epitopes to MHC class I was subsequently simulated by NetMHC 4.0 [45 (link), 46 ], also based on convolutional neural networks. The whole procedure is described in detail in our previous works [34 (link)].