{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n KRT80, a type II epithelial keratin, has emerged as a multifunctional protein that plays key roles in both normal differentiation and cancer progression. During epidermal differentiation, KRT80 mRNA is maintained at high levels by post‐transcriptional regulatory mechanisms—for example, stabilization by long non‐coding RNAs such as TINCR ensures proper terminal differentiation in human skin (a process that includes the formation of keratohyalin granules)."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " In contrast, aberrant upregulation of KRT80 in tumor cells has been linked to cytoskeletal reorganization that favors invasive behavior. In aromatase inhibitor–resistant breast cancer cells, for instance, de novo enhancer activation driven by SREBP1 leads to increased KRT80 levels, resulting in cytoskeletal rearrangements that promote focal adhesion formation, increased cellular stiffness, and enhanced cell migration and invasion."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": " Similarly, in colorectal carcinoma, elevated KRT80 expression correlates with poor prognosis, where it facilitates cancer cell migration and invasion through interaction with PRKDC and subsequent activation of the AKT pathway."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Beyond these oncogenic functions, structural and expression analyses reveal that KRT80 is widely expressed in various epithelial tissues and undergoes alternative splicing, underscoring its importance in advanced tissue differentiation and specialized cytoskeletal organization."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "4"}]}, {"type": "t", "text": " Furthermore, diverse post‐transcriptional and post‐translational mechanisms modulate its function. For example, in mouse melanocytes, lncRNA TCONS_00049140 binds to Krt80, impacting skin morphology (thickening)"}, {"type": "fg", "children": [{"type": "fg_f", "ref": "5"}]}, {"type": "t", "text": ", while in gastric cancer, a circRNA/miRNA axis (circPIP5K1A/miR-671-5p) regulates KRT80 expression to activate the PI3K/AKT pathway and drive tumor progression."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "6"}]}, {"type": "t", "text": " In addition, the deubiquitinating enzyme OTUB2 directly stabilizes KRT80 by shielding it from proteasomal degradation, which promotes gastric cancer cell proliferation via AKT signaling."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": " Environmental factors may also influence its expression; for instance, chronic cigarette smoke exposure has been associated with a significant increase in KRT80 levels in skin keratinocytes."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "8"}]}, {"type": "t", "text": "\n "}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Collectively, these studies indicate that KRT80 functions as a critical mediator of epithelial cell architecture and differentiation under physiological conditions, while its deregulated expression contributes to cytoskeletal reprogramming, increased cell motility, and tumor aggressiveness in various cancers. As such, KRT80 represents a promising prognostic biomarker and potential therapeutic target in oncology.\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Markus Kretz, Zurab Siprashvili, Ci Chu, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Control of somatic tissue differentiation by the long non-coding RNA TINCR."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Nature (2013)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/nature11661"}], "href": "https://doi.org/10.1038/nature11661"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "23201690"}], "href": "https://pubmed.ncbi.nlm.nih.gov/23201690"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Ylenia Perone, Aaron J Farrugia, Alba Rodríguez-Meira, et al. 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