Treatment of Cultured Sebocytes with an EGFR Inhibitor Does Not Lead to Significant Upregulation of Inflammatory Biomarkers.

BACKGROUND Epidermal growth factor receptor (EGFR) inhibitors are being used to treat malignancies originating from epithelia. Unfortunately, blocking the EGFR pathway leads to various side effects, most frequently acneiform eruptions. OBJECTIVE To probe the mechanism underlying this side effect, we investigated the effect of EGFR inhibitors on cultured sebocytes. METHODS To examine the effects of an EGFR inhibitor (cetuximab, Erbitux® 10 ng/ml) and the effects of EGFR ligands, such as epidermal growth factor (EGF, 10 ng/ml) and transforming growth factor-α (TGF-α, 5 ng/ml), on the production of inflammatory cytokines in cultured sebocytes, we used reverse transcriptase-polymerase chain reaction, immunocytofluorescence and Western blots. Outcomes included the expression of interleukin (IL)-1, IL-6, tumor necrosis factor-α (TNF-α), peroxisome proliferator-activated receptor-γ (PPAR-γ) and EGFR. RESULTS There were no significant differences in the expression of IL-1, IL-6, TNF-α, PPAR-γ and EGFR between (a) groups treated with an EGFR inhibitor or an EGFR ligand and (b) the control group, except for a significant increase in the expression of IL-1 in the EGF-treated group. CONCLUSION EGFR inhibitors and EGFR ligands do not provoke the expression of inflammatory biomarkers in cultured sebocytes. The role of the sebaceous glands in EGFR inhibitor-induced acneiform eruption should be investigated more thoroughly.