Among the extracellular proteins, C1s, C1r, and fibronectin, which are involved in renal fibrosis, were proteomically identified in both the LLC1 and A549 cell secretomes in the present study (Figure 3C, Tables S3 and S4), which is consistent with the study by Shin et al. [34]. The gene discussed is FN1; the disease is renal fibrosis.