FOXF1 Inhibits Pulmonary Fibrosis by Preventing CDH2-CDH11 Cadherin Switch in Myofibroblasts

Abstract

SUMMARYIdiopathic pulmonary fibrosis (IPF) is characterized by aberrant accumulation of collagen-secreting myofibroblasts. Development of effective therapies is limited due to incomplete understanding of molecular mechanisms regulating myofibroblast expansion. FOXF1 transcription factor is expressed in resident lung fibroblasts, but its role in lung fibrosis remains unknown due to the lack of genetic mouse models. Through comprehensive analysis of human IPF genomics data, lung biopsies, and transgenic mice with fibroblast-specific inactivation of FOXF1, we show that FOXF1 inhibits pulmonary fibrosis. FOXF1 deletion increases myofibroblast invasion and collagen secretion and promotes a switch from N-cadherin (CDH2) to Cadherin-11 (CDH11), which is a critical step in the acquisition of the profibrotic phenotype. FOXF1 directly binds to Cdh2 and Cdh11 promoters and differentially regulates transcription of these genes. Re-expression of CDH2 or inhibition of CDH11 in FOXF1-deficient cells reduces myofibroblast invasion in vitro. FOXF1 inhibits pulmonary fibrosis by regulating a switch from CDH2 to CDH11 in lung myofibroblasts.

The FOXM1 Inhibitor RCM-1 Decreases Carcinogenesis and Nuclear β-Catenin

“…Vehicle control and RCM-1-treated tumor cells were incubated with EdU or bromodeoxyuridine (BrdU), and immunofluorescence staining for EdU, BrdU, PH3, and Ki67 was performed as previously described (31,32).…”

“…Lung tissue sections were stained using anti-FOXM-1, anti-Ki-67, anti-PH3 (Santa Cruz Biotechnology), and anti-cleaved caspase-3 (Abcam) antibodies, as described previously (33). Tumor cells growing on coverslips were treated with 20 mmol/L of RCM-1 for 24 hours, fixed, and stained with antibodies against FOXM1, FOXA1, b-catenin, Ki-67, and a-tubulin (Santa Cruz Biotechnology) as previously described (32).…”

Klotho antagonizes pulmonary fibrosis through suppressing pulmonary fibroblasts activation, migration, and extracellular matrix production: a therapeutic implication for idiopathic pulmonary fibrosis

“…Previously, Belkhir et al reported that Foxf1 expression was induced by the antifibrotic mediator prostaglandin E2 and repressed by TGF-β in pulmonary fibroblasts [35]. The vital role of FOXF1 in the pathogenesis of IPF was later highlighted by the observation that loss of Foxf1 increased migration of pulmonary fibroblasts via facilitating CDH2-CDH11 cadherin switch and thus aggravated bleomycin-induced pulmonary fibrosis in mice [22]. Consistent with these literatures, our results showed the significant downregulation of Foxf1 in both fibrotic mice lungs and primary mouse pulmonary fibroblasts incubated with TGF-β and further demonstrated that rKL was sufficient to reverse the reduction of Foxf1, which subsequently attenuated TGF-β-induced migration of pulmonary fibroblasts through preventing CDH2-CDH11 cadherin switch.…”

“…The decreased protein levels of Foxf1 were also confirmed by western blot ( Figure 6C). Since Foxf1 has been reported to inhibit pulmonary fibrosis by preventing CDH2 to CDH11 cadherin switch in myofibroblasts during pulmonary fibrosis [22], we proposed that Kl be very likely to repress the TGF-β-induced migration of pulmonary fibroblasts via enhancing the expression of Foxf1. As hypothesized, rKL supplementation restored Foxf1 mRNA and protein levels in both PCLSs treated with FC ( Figure 6D and 6E) and pulmonary fibroblasts incubated with TGF-β ( Figure 6F and 6G).…”

“…on pulmonary fibroblasts migration against TGF-β was abolished by Foxf1 deletion (Figure 6H and 6I). Meanwhile, the expression of Cdh2 and Cdh11, the reported targets regulated by Foxf1 in pulmonary fibroblasts [22], also changed correspondingly ( Figure 6J-6M), suggesting that the genes regulated by Foxf1 could constitute an important mechanism by which Kl exerts its effect.…”