Differential expression of mRNA in human monocytes following interaction with human colon cancer cells

Anticancer Res. 2011 Jul;31(7):2493-7.


Monocytes are known to differentiate into tissue-specific macrophages in response to the tissue environment, and it has been suggested that tumor-associated macrophages might promote angiogenesis. Therefore, the factors associated with monocyte differentiation into tumor-associated macrophages may become new targets for cancer therapy. However, these factors remain unclear in human colon cancer. The aim of this study was to identify the factors associated with human monocyte differentiation into tumor-associated macrophages at human colon cancer sites.

Materials and methods: A human monocyte cell line (THP-1) was co-cultured with a human colon cancer cell line (DLD-1) and mRNA expression was analyzed by quantitative real-time PCR.

Results: In THP-1 cells, monocyte chemotactic protein (MCP)-1 mRNA expression increased in a time-dependent manner from day 3 after co-culture with DLD-1 cells; furthermore, expression of vascular endothelial growth factor (VEGF)-A, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-8 mRNA was increased from day 5. This increase in mRNA expression in the THP-1 cells was attributable to the presence of the DLD-1 cells. Therefore, MCP-1, VEGF-A, TNF-α, IL-1β, and IL-8 are suggested to be associated with differentiation of human monocytes into tumor-associated macrophages at human colon cancer sites.

MeSH terms

  • Cell Differentiation / genetics
  • Cell Line
  • Cell Line, Tumor / metabolism
  • Chemokine CCL2 / biosynthesis
  • Chemokine CCL2 / genetics
  • Coculture Techniques
  • Colonic Neoplasms / pathology*
  • Computer Systems
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Interleukin-1beta / biosynthesis
  • Interleukin-1beta / genetics
  • Interleukin-8 / biosynthesis
  • Interleukin-8 / genetics
  • Macrophages / cytology
  • Monocytes / cytology
  • Monocytes / metabolism*
  • Neovascularization, Pathologic / genetics
  • Polymerase Chain Reaction
  • RNA, Messenger / biosynthesis*
  • RNA, Messenger / genetics
  • RNA, Neoplasm / biosynthesis
  • RNA, Neoplasm / genetics
  • Tumor Necrosis Factor-alpha / biosynthesis
  • Tumor Necrosis Factor-alpha / genetics
  • Vascular Endothelial Growth Factor A / biosynthesis
  • Vascular Endothelial Growth Factor A / genetics


  • CCL2 protein, human
  • Chemokine CCL2
  • Interleukin-1beta
  • Interleukin-8
  • RNA, Messenger
  • RNA, Neoplasm
  • Tumor Necrosis Factor-alpha
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A