{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n Insulin growth factor‐like family member 1 (IGFL1) is emerging as a multifunctional secreted protein that plays key roles in both inflammatory processes and tumor progression. In skin, IGFL1 is uniquely and significantly induced in psoriatic lesions and in primary keratinocytes stimulated by tumor necrosis factor–α. IGFL1 has been shown to interact with the ectodomain of a novel receptor—IGFLR1—which is expressed primarily on T cells; this receptor–ligand pairing suggests that IGFL1 may influence T‐cell biology and thus integrate epithelial responses with adaptive immune regulation in inflammatory skin conditions."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " Furthermore, in a psoriasis classification model IGFL1, together with C10orf99, was identified as an upstream component of growth signal transduction contributing to the pathogenesis of psoriatic lesions."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": "\n "}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n In the oncologic setting, IGFL1 expression appears to be closely linked to tumor biology. In lung adenocarcinoma, IGFL1 is upregulated, correlates with larger tumor size, advanced TNM stage, and poor overall survival, while functional knockdown of IGFL1 in lung cancer cell lines reduced proliferation and enhanced apoptosis, indicating an oncogenic role."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": " A related oncogenic mechanism has been described in basal‐like breast cancer, where the long noncoding RNA IGFL2‐AS1—acting through both nuclear recruitment of a KLF5/TEAD4 transcriptional complex and cytoplasmic inhibition of a targeting microRNA—upregulates its neighboring gene IGFL1. This upregulation mediates pro‐proliferative and survival signals in tumor cells, highlighting IGFL1 as a potential therapeutic target."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "4"}]}, {"type": "t", "text": "\n "}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Environmental exposure may also impinge on IGFL1 expression. In human HaCaT keratinocytes, chronic exposure to low doses of arsenic induces a moderate increase in IGFL1 expression. This upregulation, together with altered expression of other genes, is postulated to contribute to inflammatory insults and could trigger malignant transformation in skin cells."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "5"}]}, {"type": "t", "text": "\n "}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Finally, studies characterizing the IGF‐like gene family have shown that IGFL1, expressed in fetal tissues and various cancers, likely arose from recent duplication events in the primate lineage and is distantly related to the insulin‐like growth factor superfamily. This evolutionary background further supports a role for IGFL1 in growth regulation and development, with its aberrant expression playing a role in disease states."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": "\n "}]}, {"type": "t", "text": "\n \n "}, {"type": "p", "children": [{"type": "t", "text": "\n Collectively, these findings indicate that IGFL1 functions at the intersection of immune modulation, keratinocyte biology, and oncogenesis. Its upregulation not only serves as a potential biomarker for inflammatory and neoplastic conditions but may also actively drive disease processes in both skin disorders and cancer.\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Adrian A Lobito, Sree R Ramani, Irene Tom, et al. 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"}, {"type": "b", "children": [{"type": "t", "text": "Elevated expression of IGFL1 indicates unfavorable prognosis in lung adenocarcinoma through promotion of cell proliferation and inhibition of apoptosis."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Pol J Pathol (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.5114/pjp.2021.114174"}], "href": "https://doi.org/10.5114/pjp.2021.114174"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "35308001"}], "href": "https://pubmed.ncbi.nlm.nih.gov/35308001"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Haixia Wang, Yujie Shi, Chuan-Huizi Chen, et al. "}, {"type": "b", "children": [{"type": "t", "text": "KLF5-induced lncRNA IGFL2-AS1 promotes basal-like breast cancer cell growth and survival by upregulating the expression of IGFL1."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cancer Lett (2021)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.canlet.2021.04.016"}], "href": "https://doi.org/10.1016/j.canlet.2021.04.016"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "34052325"}], "href": "https://pubmed.ncbi.nlm.nih.gov/34052325"}]}, {"type": "r", "ref": 5, "children": [{"type": "t", "text": "Mohit Rajput, Praveen Kumar Kujur, Abhijeet Mishra, et al. 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