Using a human cDNA expression array, we obtained expression profiles of 588 genes in CD14+ monocytes and monocyte-derived dendritic cells (DCs). Overall, 22 genes were upregulated, and nine genes were downregulated in DCs of both samples from two different individuals. Many of the genes that were upregulated in DCs encode proteins that are related to differentiation, cell structure, migration, termination of cell cycle as well as proliferation, e.g. tumour necrosis factor-α (TNF-α), tumour necrosis factor receptor II (TNFRII), thymosin β-10, epithelial discoidin domain receptor 1, replication factor C, putative transcription factor DB1, alpha catenin, transforming growth factor-β1, prohibitin, p53-regulating protein and neu differentiation factor. Among the downregulated genes in DCs were genes that encode proteins of cell cycle regulation: mitotic growth and transcription activator, platelet-derived growth factor receptor-β subunit, interleukin 2 receptor (IL-2R)-γ subunit, IL-7R-α subunit, leucocyte interferon-γ (IFN-γ) and granulocyte–macrophage colony-stimulating factor receptor (GM-CSFR). Semi-quantitative reverse transcription–polymerase chain reaction method confirmed the upregulated expression levels in DCs for TNFRII, TNF-α, alpha catenin and downregulation of IFN-γ, GM-CSFR on four different donor samples of DCs and monocytes. Moreover, our data show the presence of a ‘switch-on’ step for the TNF-α and TNFRII gene expression in immature DCs for further differentiation into mature DCs.