title: The long non-coding RNA TP73-AS1 modulates HCC cell proliferation through miR-200a-dependent HMGB1/RAGE regulation.
abstract: P73 antisense RNA 1 T (non-protein coding), also known as TP73-AS1, is a long non-coding RNA (lncRNA) which is involved in cell proliferation and the development of tumors. However, the exact effects and molecular mechanisms of TP73-AS1 in hepatocellular carcinoma (HCC) progression are still unknown. The present study is aimed to investigate the detailed functions and the mechanism of TP73-AS1 in regulation of HCC cell proliferation.
  
  
  
  TP73-AS1 expression in HCC tissues and cell lines was determined using real-time PCR assays; the correlation of TP73-AS1 expression with clinicopathological features of HCC was analyzed. The functions of TP73-AS1 in regulation of HCC cell proliferation was evaluated using MTT and BrdU assays. The candidate upstream miRNAs of HMGB1 were screened using miRcode, miRWalk, miRanda and Target scan, verified using real-time PCR assays. The interaction between TP73-AS1 and miR-200a was confirmed using Luciferase report gene assays. The proten levels of HMGB1 signaling-related factors in response to co-processing TP73-AS1 knockdown and miR-200a inhibition were determined using Western blot assays and ELISA. Further, miR-200a, HMGB1 mRNA and RAGE mRNA and their correlations in HCC tissues were determined.
  
  
  
  TP73-AS1 was upregulated in HCC tissues and cell lines. High TP73-AS1 expression was correlated with worse clinicopathological features, poorer prognosis and shorter survival. Knockdown of TP73-AS1 inhibited the HCC proliferation and the expression levels of HMGB1, RAGE and NF-κB in HCC cells. By using online tools, we screened out several candidate upstream miRNAs of HMGB1, among which miR-200a overexpression inhibited HMGB1 mRNA expression the most significantly. By using luciferase assays, we confirmed that miR-200a could directly bind to TP73-AS1 and the 3'UTR of HMGB1; TP73-AS1 competed with HMGB1 for miR-200a binding. MiR-200a inhibition could up-regulate HMGB1, RAGE, NF-κB expression as well as NF-κB regulated cytokines levels, which could be partially restored by si-TP73-AS1. In HCC tissues, miR-200a was down-regulated while HMGB1 and RAGE were up-regulated; TP73-AS1 was inversely correlated with miR-200a, while positively correlated with HMGB1 and RAGE, respectively.
  
  
  
  Our data indicated that TP73-AS1 might be an oncogenic lncRNA that promoted proliferation of HCC and could be regarded as a therapeutic target in human HCC.
authors.affiliation: Hunan Key Laboratory of Viral Hepatitis, Department of Infectious Disease, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Shaling
authors.initials: S
authors.lastname: Li
authors.affiliation: Hunan Key Laboratory of Viral Hepatitis, Department of Infectious Disease, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Surgery, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Hunan Key Laboratory of Viral Hepatitis, Department of Infectious Disease, Xiangya Hospital, Central South University, Changsha, 410008, China.
authors.forename: Yongming
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Surgery, University of Pittsburgh, Pittsburgh, 15260, USA.
authors.forename: Daolin
authors.initials: D
authors.lastname: Tang
authors.affiliation: Department of Surgery, University of Pittsburgh, Pittsburgh, 15260, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Kang
authors.affiliation: Hunan Key Laboratory of Viral Hepatitis, Department of Infectious Disease, Xiangya Hospital, Central South University, Changsha, 410008, China. rr_xy1234@126.com.
authors.forename: Rongrong
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Hunan Key Laboratory of Viral Hepatitis, Department of Infectious Disease, Xiangya Hospital, Central South University, Changsha, 410008, China. xgfan@hotmail.com.
authors.forename: Xue-Gong
authors.initials: XG
authors.lastname: Fan
mesh_terms: D000951:Antigens, Neoplasm / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics; D015536:Down-Regulation; D005260:Female; D055785:Gene Knockdown Techniques; D024243:HMGB1 Protein / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D008875:Middle Aged; D020928:Mitogen-Activated Protein Kinases / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D011379:Prognosis; D016372:RNA, Antisense / Q000096:biosynthesis / Q000235:genetics*; D062085:RNA, Long Noncoding / Q000096:biosynthesis / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D000072160:Tumor Protein p73 / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D000951:Antigens, Neoplasm; D024243:HMGB1 Protein; C585491:HMGB1 protein, human; C533896:MIRN200 microRNA, human; D035683:MicroRNAs; D016328:NF-kappa B; D016372:RNA, Antisense; D062085:RNA, Long Noncoding; C000606460:TP73 protein, human; D000072160:Tumor Protein p73; C498978:MOK protein, human; D020928:Mitogen-Activated Protein Kinases
keywords: HCC; HMGB1; Proliferation; TP73-AS1; lncRNA; miR-200a