title: Gene Expression in Lipopolysaccharide-treated Human Monocytes Following Interaction with Hepatic Cancer Cells.
abstract: OBJECTIVE
  Monocytes migrate into the tissue where they differentiate into various types of macrophages with tissue-specific characteristics. When human monocytes are co-cultured with colon cancer cells they exhibit increased mRNA expression of angiogenesis- and signaling pathway-related genes; however, this increase is suppressed by pretreatment with low-dose lipopolysaccharide (LPS). Thus, LPS-treated human monocytes may be useful in suppressing tumor invasion and proliferation in colon cancer. However, it is suggested that the characteristics of tumor-associated macrophages may differ depending on the type of cancer. The function of human tumor-associated macrophages in hepatic cancer remains unclear. In this study, we investigated mRNA expression of various genes in LPS-treated human monocytes following interaction with hepatic cancer cells.
  
  
  METHODS
  The human monocyte cell line THP-1 was treated with LPS and subsequently co-cultured with the human hepatic cancer cell line HepG2. mRNA expression of various factors were then analyzed using quantitative real-time polymerase chain reaction (PCR) and DNA microarray.
  
  
  RESULTS
  The mRNA expressions of monocyte chemotactic protein-1, vascular endothelial growth factor-A, tumor necrosis factor-α, interleukin (IL)-1β, IL-8, nuclear factor-κB, RelB, signal transducer and activator of transcription 3, IL-10 and transforming growth factor-β in THP-1 cells following interaction with HepG2 cells, were suppressed by pretreatment with LPS.
  
  
  CONCLUSIONS
  LPS-treated human monocytes may be useful in suppressing tumor invasion and proliferation of hepatic cancer, as well as colon cancer. The co-culture system of monocytes and cancer cells may be beneficial for evaluating antitumor effects in LPS-treated monocytes.
authors.affiliation: Department of Medical Technology, School of Life and Environmental Science, Azabu University, Sagamihara-shi, Kanagawa, Japan hondat@azabu-u.ac.jp.
authors.forename: Teruko
authors.initials: T
authors.lastname: Honda
authors.affiliation: Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan Research Institute for Healthy Living, Niigata University of Pharmacy and Applied Life Sciences, Niitsu-shi, Niigata, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inagawa
mesh_terms: D018920:Coculture Techniques; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology; D056945:Hep G2 Cells; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D008113:Liver Neoplasms / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D009000:Monocytes / Q000276:immunology / Q000378:metabolism*
chemical_list: D008070:Lipopolysaccharides
keywords: Monocyte; co-culture; hepatic cancer cell; lipopolysaccharide