We identified the loss or the downregulation of the PTPRC gene in resistant ALCL cells by two different approaches: i) an RNA-sequence analysis in crizotinb-resistant cells generated in vitro by exposing cells to increasing concentration of crizotinib, and ii) a genome-wide CRISPR/Cas9 loss-of-function screen in ALK+ ALCL cells under crizotinib treatment (30). This evidence concerns the gene PTPRC and anaplastic large cell lymphoma.