Figure 6. Promoter methylation and survival analyses of COL1A1, COL1A2, COL3A1, and FN1. (A) Promoter methylation analysis of COL1A1, COL1A2, COL3A1, and FN1 in gastric cancer (GC) and normal samples via UALCAN. (B) Promoter methylation analysis of COL1A1, COL1A2, COL3A1, and FN1 in GC and normal samples via OncoDB. P-value < 0.05.