When compared with fibroblasts from healthy lung tissues, HYAL1 was significantly upregulated in IPF lung fibroblasts at the mRNA level (P < 0.05; unpaired t test; Figure 3(a)) but not at the protein level (P > 0.05; unpaired t test; Figure 3(b)). The gene discussed is HYAL1; the disease is idiopathic pulmonary fibrosis.