{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n Fibroblast growth factor‐6 (FGF6) is emerging as a multifunctional regulator with context‐dependent roles in tissue development, regeneration, and disease. In skeletal muscle—its major site of expression—FGF6 acts in a dose‐dependent manner to modulate myogenesis. Higher FGF6 levels promote the expansion of muscle stem cells (satellite cells), thereby scaling the adult progenitor pool and enhancing regenerative capacity, whereas lower levels favor differentiation and proper myofiber specification through pathways that involve calcineurin signaling."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "1", "end_ref": "6"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Beyond muscle, FGF6 contributes to systemic energy metabolism by stimulating uncoupling protein‐1 expression in adipocytes, thereby enhancing thermogenesis. In bone tissue, it modulates cellular activities by promoting osteoblast proliferation while also enhancing osteoclast differentiation and function, thus influencing overall bone remodeling"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": "for adipose regulation;"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": "for bone effects). Epigenetic downregulation of FGF6 in skeletal muscle has been linked to metabolic dysfunction in obesity, where restoration of its levels improves muscle hypertrophy and systemic insulin sensitivity."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "8"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n In addition, aberrant FGF6 expression can contribute to oncogenic processes; for example, in bladder cancer cells, upregulation of FGF6 (mediated by regulatory long noncoding RNAs) enhances cell viability, proliferation, and migration."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "9"}]}, {"type": "t", "text": " FGF6 expression is also observed during the development of non‐muscle tissues such as the sublingual gland, where it may influence changes in secretory granule content during the perinatal period."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "10"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Overall, FGF6 plays a critical, context‐specific role by fine‑tuning cell proliferation, differentiation, and metabolic pathways in multiple tissues. Its dual function in muscle regeneration and maintenance of a progenitor pool, along with its involvement in energy homeostasis, bone remodeling, and tumor progression, makes it a promising target for therapeutic intervention in regenerative medicine, metabolic disorders, and cancer.\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Farnaz Shamsi, Ruidan Xue, Tian Lian Huang, et al. 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