Lung Fibrosis Induced by Bleomycin: Structural Changes and Overview of Recent Advances

This short review addresses the alterations induced by bleomycin in the lung, particularly those related to the induction of fibrosis. Bleomycin is a cytostatic drug commonly employed in the treatment of cancer. As a side effect of its therapeutic use, bleomycin induces in some patients chronic pulmonary inflammation that may progress to fibrosis. Endotracheal instillation of the drug has been adopted as the elective experimental model to reproduce human interstitial fibrosis of the lung in laboratory animals. We recall here the major structural alterations that are triggered by bleomycin in the lung and we overview recent literature regarding cellular and molecular mechanisms that have been identified as participants in the physiopathology of bleomycin-induced lung fibrosis. Recent data obtained with the bleomycin model have offered detailed information on the major molecular mediators of lung fibrosis. This achievement offers the hope that therapeutic strategies based on molecular medicine may have a useful role in improving the treatment of human lung fibrosis in the near future.