Using the top nine upregulated genes (CHGA, PCSK1N, TTR, DEPP1, BTG2, ATF3, SERPINA1, MDK, FOS) as a representative gene set for the lmCluster4 (Figure 5G), we calculated the GSVA score of this gene set for each patient in the TCGA gastric cancer cohort. Here, ATF3 is linked to gastric cancer.