PRF1 and colorectal carcinoma: In TCGA data set, we also found that Notch signalling pathway mutations were associated with enrichment of genes associated with immune activation pathways and higher expressions of PDCD1, GZMB and PRF1. Although Notch signalling pathway mutations did not affect the overall survival and disease‐free survival of CRC patients, they were associated with earlier disease stages and lower rates of metastasis.