Gefitinib attenuates murine pulmonary fibrosis induced by bleomycin.
BACKGROUND
Gefitinib, an inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, is an effective treatment for epithelial tumors, including non-small cell lung cancer (NSCLC), and is generally well tolerated. However, some clinical trials revealed that gefitinib exposure caused lung fibrosis, a severe adverse reaction. This study investigated the effect of gefitinib on lung fibrosis in mice.


METHODS
We generated a mouse model of lung fibrosis induced by bleomycin to investigate the fibrotic effect of gefitinib. C57BL/6 mice were injected intratracheally with bleomycin or saline, with intragastric administration of gefitinib or saline. Lung tissues were harvested on day 14 or 21 for histology and genetic analysis.


RESULTS
The histological results showed that bleomycin successfully induced lung fibrosis in mice, and gefitinib prevented lung fibrosis and suppressed the proliferation of S100A4-positive fibroblast cells. In addition, Western blotting analysis revealed that gefitinib decreased the expression of phosphorylated EGFR (p-EGFR). Furthermore, quantitative real-time PCR (qRT-PCR) demonstrated that gefitinib inhibited the accumulation of collagens I and III.


CONCLUSIONS
These results reveal that gefitinib reduces pulmonary fibrosis induced by bleomycin in mice and suggest that administration of small molecule EGFR tyrosine kinase inhibitors has the potential to prevent pulmonary fibrosis by inhibiting the proliferation of mesenchymal cells, and that targeting tyrosine kinase receptors might be useful for the treatment of pulmonary fibrosis in humans.
Wang
Ping
P
Department of Respiratory Medicine, Chinese People's Liberation Army General Hospital, Beijing 100853, China.
Tian
Qing
Q
Liang
Zhi-xin
ZX
Yang
Zhen
Z
Xu
Shu-feng
SF
Sun
Ji-ping
JP
Chen
Liang-an
LA
D000818:Animals; D001761:Bleomycin / Q000633:toxicity*; D015153:Blotting, Western; D024042:Collagen Type I / Q000235:genetics; D024061:Collagen Type III / Q000235:genetics; D066246:ErbB Receptors / Q000378:metabolism; D000077156:Gefitinib; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D011658:Pulmonary Fibrosis / Q000139:chemically induced* / Q000188:drug therapy*; D011799:Quinazolines / Q000627:therapeutic use*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D024042:Collagen Type I; D024061:Collagen Type III; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D001761:Bleomycin; C541485:EGFR protein, mouse; D066246:ErbB Receptors; D000077156:Gefitinib