A novel mechanism for anti-EGFR antibody action involves chemokine-mediated leukocyte infiltration.
Overexpression of the epidermal growth factor receptor (EGFR) is a hallmark of squamous cell carcinoma of the head and neck (SCCHN). Monoclonal antibodies (mAbs) against EGFR are currently used for therapy of recurrent or metastatic disease; however, their mode of action is not completely understood. To investigate the immunological effects of anti-EGFR mAb, we generated a three-dimensional spheroid model of EGFR-expressing SCCHN and used this model to study the effect of anti-EGFR mAb on leukocyte migration toward tumors. Pretreatment with the blocking anti-EGFR mAb EMD 72000, its F(ab')2 fragments or an EGFR tyrosine kinase inhibitor led to substantially increased leukocyte infiltration into EGFR overexpressing tumor spheroids, but not into those with low EGFR expression. Nonblocking anti-EGFR mAb or fibroblast-specific mAb did not affect leukocyte infiltration, suggesting that the observed increase in leukocyte infiltration depends on interference with EGFR activation. Using a human cytokine macroarray, we demonstrated that the blockade of EGFR by anti-EGFR mAb in EGFR-overexpressing SCCHN cells leads to differential expression of several cytokines and chemokines, including the chemokine MCP-1/CCL-2. The significant upregulation of MCP-1/CCL2 on exposure to anti-EGFR mAb was confirmed by quantitative PCR and enzyme-linked immunospot analyses. Moreover, blocking anti-MCP-1 antibody inhibited leukocyte migration toward tumor cells induced by anti-EGFR mAb, pointing to an important role of MCP-1/CCL2 in anti-EGFR mAb-induced leukocyte migration. Our findings demonstrate that anti-EGFR mAb induces leukocyte infiltration to tumor spheroids by upregulating chemokine expression. This novel mechanism for anti-EGFR mAb action may contribute to the antitumor effects of anti-EGFR mAb in vivo.
Hoffmann
Thomas K
TK
Department of Otorhinolaryngology, Heinrich-Heine-University, Düsseldorf, Germany.
Schirlau
Kerstin
K
Sonkoly
Enikö
E
Brandau
Sven
S
Lang
Stephan
S
Pivarcsi
Andor
A
Balz
Vera
V
Müller
Anja
A
Homey
Bernhard
B
Boelke
Edwin
E
Reichert
Torsten
T
Friebe-Hoffmann
Ulrike
U
Greve
Jens
J
Schuler
Patrick
P
Scheckenbach
Kathrin
K
Schipper
Jörg
J
Bas
Murat
M
Whiteside
Theresa L
TL
Bier
Henning
H
D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D061067:Antibodies, Monoclonal, Humanized; D045744:Cell Line, Tumor; D002465:Cell Movement; D018932:Chemokine CCL2 / Q000502:physiology*; D003713:Dendritic Cells / Q000502:physiology; D066246:ErbB Receptors / Q000037:antagonists & inhibitors* / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000502:physiology; D007962:Leukocytes / Q000502:physiology*; D008264:Macrophages / Q000502:physiology; D009369:Neoplasms / Q000473:pathology*; D018874:Spheroids, Cellular; D013601:T-Lymphocytes / Q000502:physiology
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; C111835:CCL2 protein, human; D018932:Chemokine CCL2; D066246:ErbB Receptors; C520777:matuzumab