ACTA2 and pulmonary fibrosis: To further explore the relationship between the five key genes and the pathogenesis of pulmonary fibrosis, we correlated the fibrosis marker genes with the key genes, and the results showed that the key genes were closely related to the extracellular matrix genes, and in particular were strongly correlated with the genes, such as ACTA2 and FN1, suggesting that there may be a potential link between the key genes of cuproptosis and the fibroblast-myofibroblast transformation, which also verified the results of the GSEA in Figure S2 (Figure 12G).