title: The microtubule-associated protein PRC1 promotes early recurrence of hepatocellular carcinoma in association with the Wnt/β-catenin signalling pathway.
abstract: Hepatocellular carcinoma (HCC) is the second leading cause of cancer mortality worldwide. Alterations in microtubule-associated proteins (MAPs) have been observed in HCC. However, the mechanisms underlying these alterations remain poorly understood. Our aim was to study the roles of the MAP protein regulator of cytokinesis 1 (PRC1) in hepatocarcinogenesis and early HCC recurrence.
  
  
  
  PRC1 expression in HCC samples was evaluated by microarray, immunoblotting and immunohistochemistry analysis. Molecular and cellular techniques including siRNA-mediated and lentiviral vector-mediated knockdown were used to elucidate the functions and mechanisms of PRC1.
  
  
  
  PRC1 expression was associated with early HCC recurrence and poor patient outcome. In HCC, PRC1 exerted an oncogenic effect by promoting cancer proliferation, stemness, metastasis and tumourigenesis. We further demonstrated that the expression and distribution of PRC1 is dynamically regulated by Wnt3a signalling. PRC1 knockdown impaired transcription factor (TCF) transcriptional activity, decreased Wnt target expression and reduced nuclear β-catenin levels. Mechanistically, PRC1 interacts with the β-catenin destruction complex, regulates Wnt3a-induced membrane sequestration of this destruction complex, inhibits adenomatous polyposis coli (APC) stability and promotes β-catenin release from the APC complex. In vivo, high PRC1 expression correlated with nuclear β-catenin and Wnt target expression. PRC1 acted as a master regulator of a set of 48 previously identified Wnt-regulated recurrence-associated genes (WRRAGs) in HCC. Thus, PRC1 controlled the expression and function of WRRAGs such as FANCI, SPC25, KIF11 and KIF23 via Wnt signalling.
  
  
  
  We identified PRC1 as a novel Wnt target that functions in a positive feedback loop that reinforces Wnt signalling to promote early HCC recurrence.
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore Institute of Molecular and Cell Biology, A*STAR, Biopolis Drive Proteos, Singapore, Singapore.
authors.forename: Jianxiang
authors.initials: J
authors.lastname: Chen
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
authors.forename: Muthukumar
authors.initials: M
authors.lastname: Rajasekaran
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
authors.forename: Hongping
authors.initials: H
authors.lastname: Xia
authors.affiliation: Institute of Molecular and Cell Biology, A*STAR, Biopolis Drive Proteos, Singapore, Singapore.
authors.forename: Xiaoqian
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
authors.forename: Shik Nie
authors.initials: SN
authors.lastname: Kong
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
authors.forename: Karthik
authors.initials: K
authors.lastname: Sekar
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
authors.forename: Veerabrahma Pratap
authors.initials: VP
authors.lastname: Seshachalam
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore.
authors.forename: Amudha
authors.initials: A
authors.lastname: Deivasigamani
authors.affiliation: Division of Surgery, Singapore General Hospital, Singapore, Singapore.
authors.forename: Brian Kim Poh
authors.initials: BK
authors.lastname: Goh
authors.affiliation: Division of Surgery, Singapore General Hospital, Singapore, Singapore.
authors.forename: London Lucien
authors.initials: LL
authors.lastname: Ooi
authors.affiliation: Institute of Molecular and Cell Biology, A*STAR, Biopolis Drive Proteos, Singapore, Singapore.
authors.forename: Wanjin
authors.initials: W
authors.lastname: Hong
authors.affiliation: Laboratory of Cancer Genomics, Division of Cellular and Molecular Research, Humphrey Oei Institute of Cancer Research, National Cancer Centre, Singapore, Singapore Institute of Molecular and Cell Biology, A*STAR, Biopolis Drive Proteos, Singapore, Singapore Cancer and Stem Cell Biology Program, Duke-National University of Singapore Graduate Medical School, Singapore, Singapore Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
authors.forename: Kam M
authors.initials: KM
authors.lastname: Hui
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000473:pathology; D018797:Cell Cycle Proteins / Q000235:genetics*; D002460:Cell Line; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics / Q000473:pathology; D008114:Liver Neoplasms, Experimental; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000235:genetics; D009364:Neoplasm Recurrence, Local / Q000235:genetics*; D051153:Wnt Proteins / Q000378:metabolism; D060449:Wnt Signaling Pathway / Q000235:genetics; D051176:beta Catenin / Q000378:metabolism
chemical_list: D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; C116662:PRC1 protein, human; D051153:Wnt Proteins; D051176:beta Catenin
keywords: CARCINOGENESIS; CELL PROLIFERATION; CELL SIGNALLING; HEPATOCELLULAR CARCINOMA; LIVER METASTASES