TGFB1 and pterygium: For example, among the TGF-β isoforms, previous studies have revealed that (1) TGF-β-1 induces collagen production in the conjunctival fibroblast which is mediated by NADPH oxidase 4 (Nox4)-related signaling [33], (2) the amniotic membrane matrix uniquely suppresses the production of TGF-β-2 and -3 [34], (3) TGF-β signaling inhibits goblet cell differentiation via the SAM-pointed domain that contains the ETS transcription factor (SPDEF) in the conjunctival epithelium [35], and (4) TGF-β signaling plays a significant profibrotic role in the pterygium via stimulating EMT [36,37].