TY - JOUR
T1 - Epithelial-to-mesenchymal transition and c-myc expression are the determinants of cetuximab-induced enhancement of squamous cell carcinoma radioresponse
AU - Skvortsova, Ira
AU - Skvortsov, Sergej
AU - Raju, Uma
AU - Stasyk, Taras
AU - Riesterer, Oliver
AU - Schottdorf, Eva Maria
AU - Popper, Bela Andre
AU - Schiestl, Bernhard
AU - Eichberger, Paul
AU - Debbage, Paul
AU - Neher, Andreas
AU - Bonn, Guenther K.
AU - Huber, Lukas A.
AU - Milas, Luka
AU - Lukas, Peter
N1 - Funding Information:
This study was supported in part by the Austrian Cancer Society/Tyrol and Merck Austria . Work in the laboratories of Lukas A. Huber and Guenther K. Bonn was supported by the Austrian Proteomics Platform (APP) within the Austrian Genome Program (GEN-AU), Vienna, Austria and the Special Research Program “Cell Proliferation and Cell Death in Tumors” ( SFB021 , Austrian Science Fund ).
PY - 2010/7
Y1 - 2010/7
N2 - Purpose: Radiation therapy cures malignant tumors of the head and neck region more effectively when it is combined with application of the anti-EGFR monoclonal antibody cetuximab. Despite the successes achieved, we still do not know how to select patients who will respond to this combination of anti-EGFR monoclonal antibody and radiation. This study was conducted to elucidate possible mechanisms which cause the combined treatment with cetuximab and irradiation to fail in some cases of squamous cell carcinomas. Methods and materials: Mice bearing FaDu and A431 squamous cell carcinoma xenograft tumors were treated with cetuximab (total dose 3 mg, intraperitoneally), irradiation (10 Gy) or their combination at the same doses. Treatment was applied when tumors reached 8 mm in size. To collect samples for further protein analysis (two-dimensional differential gel electrophoresis (2-D DIGE), mass spectrometry MALDI-TOF/TOF, Western blot analysis, and ELISA), mice from each group were sacrificed on the 8th day after the first injection of cetuximab. Other mice were subjected to tumor growth delay assay. Results: In FaDu xenografts, treatment with cetuximab alone was nearly as effective as cetuximab combined with ionizing radiation, whereas A431 tumors responded to the combined treatment with significantly enhanced delay in tumor growth. Tumors extracted from the untreated FaDu and A431 xenografts were analysed for protein expression, and 34 proteins that were differently expressed in the two tumor types were identified. The majority of these proteins are closely related to intratumoral angiogenesis, cell adhesion, motility, differentiation, epithelial-to-mesenchymal transition (EMT), c-myc signaling and DNA repair. Conclusions: The failure of cetuximab to enhance radiation response in FaDu xenografts was associated with the initiation of the program of EMT and with c-myc up-regulation in the carcinoma cells. For this reason, c-myc and EMT-related proteins (E-cadherin, vimentin) may be considered as potential biomarkers to predict squamous cell carcinoma response after treatment with cetuximab in combination with radiation.
AB - Purpose: Radiation therapy cures malignant tumors of the head and neck region more effectively when it is combined with application of the anti-EGFR monoclonal antibody cetuximab. Despite the successes achieved, we still do not know how to select patients who will respond to this combination of anti-EGFR monoclonal antibody and radiation. This study was conducted to elucidate possible mechanisms which cause the combined treatment with cetuximab and irradiation to fail in some cases of squamous cell carcinomas. Methods and materials: Mice bearing FaDu and A431 squamous cell carcinoma xenograft tumors were treated with cetuximab (total dose 3 mg, intraperitoneally), irradiation (10 Gy) or their combination at the same doses. Treatment was applied when tumors reached 8 mm in size. To collect samples for further protein analysis (two-dimensional differential gel electrophoresis (2-D DIGE), mass spectrometry MALDI-TOF/TOF, Western blot analysis, and ELISA), mice from each group were sacrificed on the 8th day after the first injection of cetuximab. Other mice were subjected to tumor growth delay assay. Results: In FaDu xenografts, treatment with cetuximab alone was nearly as effective as cetuximab combined with ionizing radiation, whereas A431 tumors responded to the combined treatment with significantly enhanced delay in tumor growth. Tumors extracted from the untreated FaDu and A431 xenografts were analysed for protein expression, and 34 proteins that were differently expressed in the two tumor types were identified. The majority of these proteins are closely related to intratumoral angiogenesis, cell adhesion, motility, differentiation, epithelial-to-mesenchymal transition (EMT), c-myc signaling and DNA repair. Conclusions: The failure of cetuximab to enhance radiation response in FaDu xenografts was associated with the initiation of the program of EMT and with c-myc up-regulation in the carcinoma cells. For this reason, c-myc and EMT-related proteins (E-cadherin, vimentin) may be considered as potential biomarkers to predict squamous cell carcinoma response after treatment with cetuximab in combination with radiation.
KW - Angiogenesis
KW - Cetuximab
KW - Epithelial-to-mesenchymal transition (EMT)
KW - Radiation
KW - Squamous cell carcinoma
KW - c-myc
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U2 - 10.1016/j.radonc.2010.04.017
DO - 10.1016/j.radonc.2010.04.017
M3 - Article
C2 - 20451273
AN - SCOPUS:77953960942
SN - 0167-8140
VL - 96
SP - 108
EP - 115
JO - Radiotherapy and Oncology
JF - Radiotherapy and Oncology
IS - 1
ER -