title: Tim-3 fosters HCC development by enhancing TGF-β-mediated alternative activation of macrophages.
abstract: OBJECTIVE
  Tumour-associated macrophages (TAMs) and their alternative activation contribute greatly to the development of hepatocellular carcinoma (HCC). Tim-3 is highly expressed on macrophages and regulates macrophage functions in several conditions. However, whether Tim-3 is involved in the activation and the function of TAMs has not been reported.
  
  
  METHODS
  Tim-3 expression in HCC samples was evaluated by flow cytometry, immunohistochemistry and confocal analysis. We analysed the effects of Tim-3 knockdown on macrophages in growth of H22 tumour homografts in BALB/c mice. Tim-3 interference was performed by neutralising antibody, small interfering RNA or short hairpin RNA-expressing lentivirus. Cytokine production was evaluated by reverse transcription PCR, ELISA or Cytometric Bead Array. The effects of Tim-3 interference in macrophages were examined with regard to alternative activation of macrophages and proliferation and migration of Hepa1-6 cells. Cell growth curve, colony formation and transwell assays were involved to estimate cell proliferation and migration.
  
  
  RESULTS
  Tim-3 expression was significantly increased in both peripheral blood monocytes and TAMs in patients with HCC. The Tim-3 expression in monocytes/TAMs strongly correlated with higher tumour grades and the poor survival of patients with HCC. Consistently, HCC conditioned medium or transforming growth factor-β fostered Tim-3 expression and the alternative activation of macrophages. Moreover, Tim-3 interference in macrophages significantly inhibited the alternative activation of macrophages and suppressed HCC cell growth both in vitro and in vivo. Blocking interleukin 6 reversed the Tim-3-mediated effects on HCC cell growth in vitro.
  
  
  CONCLUSIONS
  Tim-3 displays critical roles in microenvironment-induced activation and protumoral effects of TAMs in HCC. Interference of Tim-3 might be great potential in HCC therapy.
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Wenjiang
authors.initials: W
authors.lastname: Yan
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Hongxin
authors.identifier: http://orcid.org/0000-0002-8121-4718
authors.initials: H
authors.lastname: Ma
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Hualin
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Song
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Lifen
authors.initials: L
authors.lastname: Gao
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Liang
authors.affiliation: Key Laboratory for Experimental Teratology of Ministry of Education and Department of Immunology, Shandong University School of Medicine, Jinan, China.
authors.forename: Chunhong
authors.identifier: http://orcid.org/0000-0002-8121-4718
authors.initials: C
authors.lastname: Ma
mesh_terms: D000818:Animals; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D000072597:Hepatitis A Virus Cellular Receptor 2; D006801:Humans; D007150:Immunohistochemistry; D008114:Liver Neoplasms, Experimental / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008262:Macrophage Activation / Q000235:genetics*; D008264:Macrophages / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D018613:Microscopy, Confocal; D012334:RNA, Neoplasm / Q000235:genetics*; D011991:Receptors, Virus / Q000096:biosynthesis / Q000235:genetics*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics*
chemical_list: C442241:Havcr2 protein, mouse; D000072597:Hepatitis A Virus Cellular Receptor 2; D012334:RNA, Neoplasm; D011991:Receptors, Virus; D016212:Transforming Growth Factor beta
keywords: CANCER IMMUNOBIOLOGY; HEPATOMA; KUPFFER CELL; MOLECULAR IMMUNOLOGY; TGF-BETA