TGFB1 and pterygium: A number of studies have relatively frequently reported the role of other ECM components in pterygium not related to fibroblasts or TGF-β, such as MMPs [29], different growth factors (PDGF, bFGF, HB-EGFM, and VEGF) [18,38], or inflammatory mediators, such as IL-6 and IL-8 [42].