Bemarituzumab Suppresses Choroidal Neovascularization in Mice by Downregulating Melanoma Cell Adhesion Molecule and Yes-Associated Protein 1

In recent years, some fibroblast growth factors (FGFs) have been reported to be promising therapeutic targets for neovascular age-related macular degeneration (nAMD). Interestingly, we found that the FGFR2b inhibitor bemarituzumab (FPA144) exerts a beneficial effect in a mouse choroidal neovascularization (CNV) model. Our current study aims to uncover the potential molecular mechanism by which FPA144 alleviates CNV. The effect of FPA144 was evaluated in a laser-induced CNV mouse model. Fundus fluorescein angiography (FFA), optical coherence tomography (OCT), and choroidal flat mounts were carried out for the quantitative assessment of CNV. Label-free quantitative proteomics analysis was performed to assess changes in molecular pathways. Primary cultured human umbilical vein endothelial cells (HUVECs) were used for further confirmation of the target pathway in vitro. FFA, OCT, and choroidal flat mounts demonstrate the protective effect of FPA144 in a mouse CNV model. Compared to the control group, the treated group has smaller vascular leakage areas or smaller CNV lesions. Proteomic analyses indicate that the melanoma cell adhesion molecule (MCAM, CD146)–Yes-associated protein 1 (Yap1) pathway may be involved in the effect of FPA144. Immunostaining of choroidal flat mounts and cryosections reveals decreased expression of CD146 and Yap1 in the vascular endothelial cells of the treated animals. Experiments on HUVECs further verify the inhibitory effect of FPA144 on vascular endothelial cells. Our findings demonstrate that FPA144 can efficiently inhibit the development of choroidal neovascularization in mice by downregulating CD146 and Yap1.