Tomohito Yoshihara1, Yasuhiro Nanri1, Satoshi Nunomura1, Yukie Yamaguchi2, Carol Feghali-Bostwick3, Keiichi Ajito4, Shoichi Murakami4, Masaaki Mawatari5, Kenji Izuhara6. 1. Division of Medical Biochemistry, Department of Biomolecular Sciences, Saga Medical School, 5-1-1 Nabeshima, Saga, 849-8501, Japan. 2. Department of Environmental Immuno-Dermatology, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan. 3. Division of Rheumatology and Immunology, Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA. 4. Pharmaceutical Research Center, Meiji Seika Pharma Co. Ltd., Yokohama, 222-8567, Japan. 5. Department of Orthopaedic Surgery, Saga Medical School, Saga, 849-8501, Japan. 6. Division of Medical Biochemistry, Department of Biomolecular Sciences, Saga Medical School, 5-1-1 Nabeshima, Saga, 849-8501, Japan. kizuhara@cc.saga-u.ac.jp.
Abstract
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a devastating disease with a median survival of only three to 5 years. Fibroblast proliferation is a hallmark of IPF as is secretion of extracellular matrix proteins from fibroblasts. However, it is still uncertain how IPF fibroblasts acquire the ability to progressively proliferate. Periostin is a matricellular protein highly expressed in the lung tissues of IPF patients, playing a critical role in the pathogenesis of pulmonary fibrosis. However, it remains undetermined whether periostin affects lung fibroblast proliferation. METHODS: In this study, we first aimed at identifying periostin-dependently expressed genes in lung fibroblasts using DNA microarrays. We then examined whether expression of cyclins and CDKs controlling cell cycle progression occur in a periostin-dependent manner. We next examined whether downregulation of cell proliferation-promoting genes by knockdown of periostin or integrin, a periostin receptor, using siRNA, is reflected in the cell proliferation of lung fibroblasts. We then looked at whether lung fibroblasts derived from IPF patients also require periostin for maximum proliferation. We finally investigated whether CP4715, a potent inhibitor against integrin αVβ3 (a periostin receptor), which we have recently found blocks TGF-β signaling, followed by reduced BLM-induced pulmonary fibrosis in mice, can block proliferation of lung fibroblasts derived from IPF patients. RESULTS: Many cell-cycle-related genes are involved in the upregulated or downregulated genes by periostin knockdown. We confirmed that in lung fibroblasts, periostin silencing downregulates expression of several cell-cycle-related molecules, including the cyclin, CDK, and, E2F families, as well as transcription factors such as B-MYB and FOXM1. Periostin or integrin silencing slowed proliferation of lung fibroblasts and periostin silencing increased the distribution of the G0/G1 phase, whereas the distribution of the G2/M phase was decreased. Lung fibroblasts derived from IPF patients also required periostin for maximum proliferation. Moreover, CP4715 downregulated proliferation along with expression of cell-cycle-related genes in IPF lung fibroblasts as well as in normal lung fibroblasts. CONCLUSIONS: Periostin plays a critical role in the proliferation of lung fibroblasts and the present results provide us a solid basis for considering inhibitors of the periostin/integrin αVβ3 interaction for the treatment of IPF patients.
BACKGROUND:Idiopathic pulmonary fibrosis (IPF) is a devastating disease with a median survival of only three to 5 years. Fibroblast proliferation is a hallmark of IPF as is secretion of extracellular matrix proteins from fibroblasts. However, it is still uncertain how IPF fibroblasts acquire the ability to progressively proliferate. Periostin is a matricellular protein highly expressed in the lung tissues of IPFpatients, playing a critical role in the pathogenesis of pulmonary fibrosis. However, it remains undetermined whether periostin affects lung fibroblast proliferation. METHODS: In this study, we first aimed at identifying periostin-dependently expressed genes in lung fibroblasts using DNA microarrays. We then examined whether expression of cyclins and CDKs controlling cell cycle progression occur in a periostin-dependent manner. We next examined whether downregulation of cell proliferation-promoting genes by knockdown of periostin or integrin, a periostin receptor, using siRNA, is reflected in the cell proliferation of lung fibroblasts. We then looked at whether lung fibroblasts derived from IPFpatients also require periostin for maximum proliferation. We finally investigated whether CP4715, a potent inhibitor against integrin αVβ3 (a periostin receptor), which we have recently found blocks TGF-β signaling, followed by reduced BLM-induced pulmonary fibrosis in mice, can block proliferation of lung fibroblasts derived from IPFpatients. RESULTS: Many cell-cycle-related genes are involved in the upregulated or downregulated genes by periostin knockdown. We confirmed that in lung fibroblasts, periostin silencing downregulates expression of several cell-cycle-related molecules, including the cyclin, CDK, and, E2F families, as well as transcription factors such as B-MYB and FOXM1. Periostin or integrin silencing slowed proliferation of lung fibroblasts and periostin silencing increased the distribution of the G0/G1 phase, whereas the distribution of the G2/M phase was decreased. Lung fibroblasts derived from IPFpatients also required periostin for maximum proliferation. Moreover, CP4715 downregulated proliferation along with expression of cell-cycle-related genes in IPF lung fibroblasts as well as in normal lung fibroblasts. CONCLUSIONS:Periostin plays a critical role in the proliferation of lung fibroblasts and the present results provide us a solid basis for considering inhibitors of the periostin/integrin αVβ3 interaction for the treatment of IPFpatients.
Authors: Georgios Theocharidis; Beena E Thomas; Debasree Sarkar; Hope L Mumme; William J R Pilcher; Bhakti Dwivedi; Teresa Sandoval-Schaefer; Ruxandra F Sîrbulescu; Antonios Kafanas; Ikram Mezghani; Peng Wang; Antonio Lobao; Ioannis S Vlachos; Biraja Dash; Henry C Hsia; Valerie Horsley; Swati S Bhasin; Aristidis Veves; Manoj Bhasin Journal: Nat Commun Date: 2022-01-10 Impact factor: 14.919