To determine whether ARRB2 expression was associated with common pathways and gene sets of cancer, we selected top 15 LTTs with down-regulated ARRB2 (Supplementary Fig. S3, red bars) and performed GSEA (https://www.gsea-msigdb.org) between 15 LTTs and matched 15 LNTs. The gene discussed is ARRB2; the disease is cancer.