{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nIn glioma, ST7‐AS1 is expressed at lower levels than in normal brain tissues where it functions as a tumor suppressor. p53 transcriptionally activates ST7‐AS1, and its upregulation leads to reduced cell migration, invasion, and proliferation, as well as enhanced apoptosis. Mechanistically, ST7‐AS1 binds directly to and downregulates PTBP1 at the post-transcriptional level, thereby inhibiting Wnt/β‐catenin signaling; this establishes a positive feedback loop within the p53/ST7‐AS1/PTBP1 axis that helps restrain glioma progression."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn contrast, in laryngeal squamous cell carcinoma ST7‐AS1 is overexpressed and acts oncogenically. Its elevated expression is critical for promoting malignant traits such as enhanced cell migration, tumor sphere formation, and tumorigenesis in vivo. ST7‐AS1 exerts its pro-tumorigenic effects by interacting with and stabilizing CARM1, a protein arginine methyltransferase, thereby preventing its ubiquitin-dependent degradation. This stabilization facilitates the methylation and subsequent activation of Sox-2, thus driving a CARM1/Sox-2 signaling axis that supports cancer development."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAdditionally, in the context of cisplatin-resistant gastric cancer, cancer-associated fibroblast–derived midkine was found to upregulate ST7‐AS1, which in turn promotes epithelial–mesenchymal transition and activates the PI3K/AKT pathway. Silencing ST7‐AS1 in these cells increases their sensitivity to cisplatin by inhibiting EMT and reducing PI3K/AKT phosphorylation, thereby attenuating drug resistance. These findings reveal a novel mechanism whereby the upregulation of ST7‐AS1 by tumor microenvironment factors contributes to chemoresistance."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": ""}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Jie Sheng, Xin He, Wei Yu, et al. "}, {"type": "b", "children": [{"type": "t", "text": "p53-targeted lncRNA ST7-AS1 acts as a tumour suppressor by interacting with PTBP1 to suppress the Wnt/β-catenin signalling pathway in glioma."}]}, {"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.2020.12.039"}], "href": "https://doi.org/10.1016/j.canlet.2020.12.039"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "33476649"}], "href": "https://pubmed.ncbi.nlm.nih.gov/33476649"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Haiping Qin, Jinxia Xu, Lili Gong, et al. "}, {"type": "b", "children": [{"type": "t", "text": "The long noncoding RNA ST7-AS1 promotes laryngeal squamous cell carcinoma by stabilizing CARM1."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Biochem Biophys Res Commun (2019)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.bbrc.2019.02.057"}], "href": "https://doi.org/10.1016/j.bbrc.2019.02.057"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "30853182"}], "href": "https://pubmed.ncbi.nlm.nih.gov/30853182"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Ke-Da Yang, Ying Wang, Fan Zhang, et al. "}, {"type": "b", "children": [{"type": "t", "text": "CAF-derived midkine promotes EMT and cisplatin resistance by upregulating lncRNA ST7-AS1 in gastric cancer."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Mol Cell Biochem (2022)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1007/s11010-022-04436-x"}], "href": "https://doi.org/10.1007/s11010-022-04436-x"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "35588343"}], "href": "https://pubmed.ncbi.nlm.nih.gov/35588343"}]}]}]}