Moreover, we observed that both CD4+ and CD8+ T cells have more clonal T cells, which are derived from identical TCR clonotypes and consistent with a previous study17, in the tumours compared to the PBMC, suggesting the clonal expansion of certain dominant clones of tumour infiltrating T cells upon continuous stimulations by tumour antigens (Supplementary Fig. 3c). This evidence concerns the gene CD8A and neoplasm.