2.4. TMB and tumor immune microenvironment
CRC
INFILTRATION
TMB is defined as the total number of mutations per million bases and was reported to be related with immune checkpoint inhibitors.To explore the correlation between degree of immune cell infiltration and risk score, ESTIMATE algorithm was performed to calculate Immune score, Stromal score and Estimate score using “estimate” package. Additionally, the proportion of 22 marked immune cell subtypes in CRC patients was also calculated via “CIBERSORT” package. Next, the Wilcoxon’s test was conducted to compared the differences of 22 immune cell subtypes between high-risk group and low-risk group. And Spearman correlation test was used to evaluate the relationship between risk score and immune cell subtypes.