To explore whether BECN1 participates in silica-induced pulmonary fibrosis, we tested the BECN1 levels in fibrotic lung tissue and found that BECN1 exhibited a decreasing trend on day 14 and day 28 after silica treatment compared with those in the saline group (Figure 4C and Supplementary Table S6). Here, BECN1 is linked to pulmonary fibrosis.