{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nResearch across multiple cancer types indicates that miR‑520f functions predominantly as a tumor suppressor. In neuroblastoma, decreased miR‑520f levels lead to the derepression of NAIP (the neural apoptosis inhibitory protein), contributing to drug resistance through reduced apoptosis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " In non‐small cell lung cancer (NSCLC), a circular RNA (circ_0043278) sponges miR‑520f, thereby diminishing its inhibitory effects on targets such as ROCK1, CDKN1B, and AKT3. This sponging event results in enhanced proliferation, invasion, and migration of tumor cells."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": " Moreover, in lung cancer, downregulation of serum miR‑520f is associated with advanced TNM stage and metastasis, suggesting its utility as a non‑invasive diagnostic biomarker."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn gastrointestinal and hepatic malignancies, miR‑520f maintains similar tumor‑suppressive functions. In gastric carcinoma, miR‑520f downregulation is linked to increased expression of factors such as ATAD2 and SOX9, leading to enhanced tumor cell growth, larger tumor size, and distant metastasis. Restoration of miR‑520f levels thereby inhibits proliferation by targeting these oncogenic molecules."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "4"}]}, {"type": "t", "text": " In hepatocellular carcinoma, reduced expression of miR‑520f results in upregulation of TM4SF1, which in turn activates the PI3K/AKT and p38 MAPK pathways, promoting cell proliferation, invasion, and migration."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "6"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAdditional evidence further substantiates the critical tumor‑suppressive role of miR‑520f. In cholangiocarcinoma, the long noncoding RNA SNHG20 acts as a competing endogenous RNA by sponging miR‑520f‑3p, leading to enhanced tumor cell proliferation and correlating with poor patient prognosis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": " In breast cancer, a polymorphism in the mir‑520f gene (rs75598818) is predicted to affect the stability of its stem‑loop structure, thereby altering production of the mature miR‑520f‑3p. This genetic variation is associated with modifications in cancer risk and HER‑2 positive status."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "8"}]}, {"type": "t", "text": " In prostate cancer, a circRNA (hsa_circ_0006220) sequesters miR‑520f‑3p, which leads to de‑repression of the cell division cycle‑associated 7 (CDCA7) gene, thereby promoting cell proliferation, migration, invasion, and metastasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "9"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Harry Harvey, Olga Piskareva, Laura Creevey, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Modulation of chemotherapeutic drug resistance in neuroblastoma SK-N-AS cells by the neural apoptosis inhibitory protein and miR-520f."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Int J Cancer (2015)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/ijc.29144"}], "href": "https://doi.org/10.1002/ijc.29144"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "25137037"}], "href": "https://pubmed.ncbi.nlm.nih.gov/25137037"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Jinggang Cui, Wei Li, Guohua Liu, et al. "}, {"type": "b", "children": [{"type": "t", "text": "A novel circular RNA, hsa_circ_0043278, acts as a potential biomarker and promotes non-small cell lung cancer cell proliferation and migration by regulating miR-520f."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Artif Cells Nanomed Biotechnol (2019)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1080/21691401.2019.1575847"}], "href": "https://doi.org/10.1080/21691401.2019.1575847"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "30873868"}], "href": "https://pubmed.ncbi.nlm.nih.gov/30873868"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Yingyan Zhou, Shimo Shen "}, {"type": "b", "children": [{"type": "t", "text": "MiR-520f acts as a biomarker for the diagnosis of lung cancer."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Medicine (Baltimore) (2019)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1097/MD.0000000000016546"}], "href": "https://doi.org/10.1097/MD.0000000000016546"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "31348274"}], "href": "https://pubmed.ncbi.nlm.nih.gov/31348274"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "S Hong, M Bi, S Chen, et al. "}, {"type": "b", "children": [{"type": "t", "text": "MicroRNA-520f suppresses growth of gastric carcinoma cells by target ATPase family AAA domain-containing protein 2 (ATAD2)."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Neoplasma (2016)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.4149/neo_2016_606"}], "href": "https://doi.org/10.4149/neo_2016_606"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "27565325"}], "href": "https://pubmed.ncbi.nlm.nih.gov/27565325"}]}, {"type": "r", "ref": 5, "children": [{"type": "t", "text": "Jian-Qing Chen, Zhi-Ping Huang, Hui-Fen Li, et al. "}, {"type": "b", "children": [{"type": "t", "text": "MicroRNA-520f-3p inhibits proliferation of gastric cancer cells via targeting SOX9 and thereby inactivating Wnt signaling."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Sci Rep (2020)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/s41598-020-63279-y"}], "href": "https://doi.org/10.1038/s41598-020-63279-y"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "32277152"}], "href": "https://pubmed.ncbi.nlm.nih.gov/32277152"}]}, {"type": "r", "ref": 6, "children": [{"type": "t", "text": "Xiaoqin Du, Wanhu Fan, Yunru Chen "}, {"type": "b", "children": [{"type": "t", "text": "microRNA-520f inhibits hepatocellular carcinoma cell proliferation and invasion by targeting TM4SF1."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Gene (2018)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.gene.2018.03.003"}], "href": "https://doi.org/10.1016/j.gene.2018.03.003"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "29505836"}], "href": "https://pubmed.ncbi.nlm.nih.gov/29505836"}]}, {"type": "r", "ref": 7, "children": [{"type": "t", "text": "Canghai Guan, Yuqiao Zhao, Weina Wang, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Knockdown of lncRNA SNHG20 Suppressed the Proliferation of Cholangiocarcinoma by Sponging miR-520f-3p."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cancer Biother Radiopharm (2024)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1089/cbr.2020.4042"}], "href": "https://doi.org/10.1089/cbr.2020.4042"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "32907346"}], "href": "https://pubmed.ncbi.nlm.nih.gov/32907346"}]}, {"type": "r", "ref": 8, "children": [{"type": "t", "text": "Marzieh Meshkat, Hamzeh Mesrian Tanha, Kamran Ghaedi, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Association of a potential functional mir-520f rs75598818 G>A polymorphism with breast cancer."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Genet (2018)"}]}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "30555079"}], "href": "https://pubmed.ncbi.nlm.nih.gov/30555079"}]}, {"type": "r", "ref": 9, "children": [{"type": "t", "text": "Zijin Wan, Gang Liu "}, {"type": "b", "children": [{"type": "t", "text": "Circ_0006220 (circ-TADA2A) accelerates prostate cancer cell malignant behaviors through miR-520f-3p/CDCA7 axis."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cell Mol Biol (Noisy-le-grand) (2024)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.14715/cmb/2024.70.7.12"}], "href": "https://doi.org/10.14715/cmb/2024.70.7.12"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "39097891"}], "href": "https://pubmed.ncbi.nlm.nih.gov/39097891"}]}]}]}