| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Regular Articles |
Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
Epidermal growth factor (EGF) receptor (EGFR) is commonly amplified and/or mutated in high-grade gliomas. Abnormal signaling from this receptor tyrosine kinase is believed to contribute to the malignant phenotypes seen in these tumors. Highly specific small molecule inhibitors of this receptor tyrosine kinase have been developed and may potentially improve the treatment of these highly aggressive brain tumors. A glioma cell line overexpressing EGFR was developed to mimic the situation of a malignant glioma with amplified EGFR, and this line was used to characterize the response to specific EGFR inhibitors. Treatment of our in vitro glioma model with the EGFR kinase inhibitors ZD1839 (Iressa) or PD153035, synthetic anilinoquinazolines with high specificity for EGFR, resulted in significant suppression of EGFR autophosphorylation even with very low levels of drug. However, significantly higher levels of drug were required to fully inhibit signaling through the phosphatidylinositol 3'-kinase/AKT and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (ERK) pathways. Interestingly, not all downstream signaling pathways displayed this resistance to inhibition. EGF-dependent activation of signal transducers and activators of transcription-3 occurred at low doses of EGFR inhibitors. The uncoupling of EGFR autophosphorylation and signaling through AKT and ERK was not dependent on EGFR overexpression. In addition, although this response was seen in other glioma and the SK-BR3 breast cancer cell lines, it was not universally present. The SQ20B head and neck squamous carcinoma cell line demonstrated loss of EGF-dependent AKT and ERK activation even at low doses of inhibitor. Despite significant loss of EGF-dependent autophosphorylation, the inability of low levels of EGFR inhibitor to suppress some downstream signaling pathways in our model glioma cell line permitted continued EGF-responsive decreases in the expression of the cyclin-dependent kinase inhibitor p27KIP and EGF-dependent proliferation/cell cycle progression. Although the mechanism responsible for the differential sensitivity of the various signal transduction pathways to EGFR inhibitors remains unclear, signaling through erbB2 does not appear to be involved. The ability of certain tumor cells to maintain signaling through AKT and ERK under EGFR inhibition may represent a potential mechanism of resistance by which a tumor cell may escape the antiproliferative activity of this new class of drugs.
This article has been cited by other articles:
![]() |
D. Meco, T. Servidei, A. Riccardi, C. Ferlini, G. Cusano, G. F. Zannoni, F. Giangaspero, and R. Riccardi Antitumor effect in medulloblastoma cells by gefitinib: Ectopic HER2 overexpression enhances gefitinib effects in vivo Neuro-oncol, January 1, 2009; 11(3): 250 - 259. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Nakamura, E. Garcia, and R. O. Pieper S6K1 Plays a Key Role in Glial Transformation Cancer Res., August 15, 2008; 68(16): 6516 - 6523. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Sampaio, M. Dance, A. Montagner, T. Edouard, N. Malet, B. Perret, A. Yart, J.-P. Salles, and P. Raynal Signal Strength Dictates Phosphoinositide 3-Kinase Contribution to Ras/Extracellular Signal-Regulated Kinase 1 and 2 Activation via Differential Gab1/Shp2 Recruitment: Consequences for Resistance to Epidermal Growth Factor Receptor Inhibition Mol. Cell. Biol., January 15, 2008; 28(2): 587 - 600. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Xu and H.-K. G. Shu EGFR Activation Results in Enhanced Cyclooxygenase-2 Expression through p38 Mitogen-Activated Protein Kinase-Dependent Activation of the Sp1/Sp3 Transcription Factors in Human Gliomas Cancer Res., July 1, 2007; 67(13): 6121 - 6129. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. G. Johns, R. M. Perera, S. C. Vernes, A. A. Vitali, D. X. Cao, W. K. Cavenee, A. M. Scott, and F. B. Furnari The Efficacy of Epidermal Growth Factor Receptor-Specific Antibodies against Glioma Xenografts Is Influenced by Receptor Levels, Activation Status, and Heterodimerization Clin. Cancer Res., March 15, 2007; 13(6): 1911 - 1925. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. K. Nicholas, R. V. Lukas, N. F. Jafri, L. Faoro, and R. Salgia Epidermal Growth Factor Receptor-Mediated Signal Transduction in the Development and Therapy of Gliomas Clin. Cancer Res., December 15, 2006; 12(24): 7261 - 7270. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. R Hutcheson, J. M Knowlden, H. E Jones, R. S Burmi, R. A McClelland, D. Barrow, J. M W Gee, and R. I Nicholson Inductive mechanisms limiting response to anti-epidermal growth factor receptor therapy Endocr. Relat. Cancer, December 1, 2006; 13(Supplement_1): S89 - S97. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Guo, J. Lu, A. Subramanian, and G. E. Sonenshein Microarray-Assisted Pathway Analysis Identifies Mitogen-Activated Protein Kinase Signaling as a Mediator of Resistance to the Green Tea Polyphenol Epigallocatechin 3-Gallate in Her-2/neu-Overexpressing Breast Cancer Cells. Cancer Res., May 15, 2006; 66(10): 5322 - 5329. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Akasaki, G. Liu, H. H. Matundan, H. Ng, X. Yuan, Z. Zeng, K. L. Black, and J. S. Yu A Peroxisome Proliferator-activated Receptor-{gamma} Agonist, Troglitazone, Facilitates Caspase-8 and -9 Activities by Increasing the Enzymatic Activity of Protein-tyrosine Phosphatase-1B on Human Glioma Cells J. Biol. Chem., March 10, 2006; 281(10): 6165 - 6174. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Reardon, J. A. Quinn, J. J. Vredenburgh, S. Gururangan, A. H. Friedman, A. Desjardins, S. Sathornsumetee, J. E. Herndon II, J. M. Dowell, R. E. McLendon, et al. Phase 1 Trial of Gefitinib Plus Sirolimus in Adults with Recurrent Malignant Glioma Clin. Cancer Res., February 1, 2006; 12(3): 860 - 868. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. N. Rich, S. Sathornsumetee, S. T. Keir, M. W. Kieran, A. Laforme, A. Kaipainen, R. E. McLendon, M. W. Graner, B.K. A. Rasheed, L. Wang, et al. ZD6474, a Novel Tyrosine Kinase Inhibitor of Vascular Endothelial Growth Factor Receptor and Epidermal Growth Factor Receptor, Inhibits Tumor Growth of Multiple Nervous System Tumors Clin. Cancer Res., November 15, 2005; 11(22): 8145 - 8157. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. E. Bates and T. Fojo Epidermal Growth Factor Receptor Inhibitors: A Moving Target? Clin. Cancer Res., October 15, 2005; 11(20): 7203 - 7205. [Full Text] [PDF] |
||||
![]() |
L. Yuan, K. Choi, C. Khosla, X. Zheng, R. Higashikubo, M. R. Chicoine, and K. M. Rich Tissue transglutaminase 2 inhibition promotes cell death and chemosensitivity in glioblastomas Mol. Cancer Ther., September 1, 2005; 4(9): 1293 - 1302. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Jain, C. A. Tindell, I. Laux, J. B. Hunter, J. Curran, A. Galkin, D. E. Afar, N. Aronson, S. Shak, R. B. Natale, et al. Epithelial membrane protein-1 is a biomarker of gefitinib resistance PNAS, August 16, 2005; 102(33): 11858 - 11863. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Lamszus, M. A. Brockmann, C. Eckerich, P. Bohlen, C. May, U. Mangold, R. Fillbrandt, and M. Westphal Inhibition of Glioblastoma Angiogenesis and Invasion by Combined Treatments Directed Against Vascular Endothelial Growth Factor Receptor-2, Epidermal Growth Factor Receptor, and Vascular Endothelial-Cadherin Clin. Cancer Res., July 1, 2005; 11(13): 4934 - 4940. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. F. Petricoin III, V. E. Bichsel, V. S. Calvert, V. Espina, M. Winters, L. Young, C. Belluco, B. J. Trock, M. Lippman, D. A. Fishman, et al. Mapping Molecular Networks Using Proteomics: A Vision for Patient-Tailored Combination Therapy J. Clin. Oncol., May 20, 2005; 23(15): 3614 - 3621. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Marie, A. F. Carpentier, A.M.P. Omuro, M. Sanson, J. Thillet, K. Hoang-Xuan, and J. -Y. Delattre EGFR tyrosine kinase domain mutations in human gliomas Neurology, April 26, 2005; 64(8): 1444 - 1445. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Brehmer, Z. Greff, K. Godl, S. Blencke, A. Kurtenbach, M. Weber, S. Muller, B. Klebl, M. Cotten, G. Keri, et al. Cellular Targets of Gefitinib Cancer Res., January 15, 2005; 65(2): 379 - 382. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. K. Goudar, Q. Shi, M. D. Hjelmeland, S. T. Keir, R. E. McLendon, C. J. Wikstrand, E. D. Reese, C. A. Conrad, P. Traxler, H. A. Lane, et al. Combination therapy of inhibitors of epidermal growth factor receptor/vascular endothelial growth factor receptor 2 (AEE788) and the mammalian target of rapamycin (RAD001) offers improved glioblastoma tumor growth inhibition Mol. Cancer Ther., January 1, 2005; 4(1): 101 - 112. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Huang, E. A. Armstrong, S. Benavente, P. Chinnaiyan, and P. M. Harari Dual-Agent Molecular Targeting of the Epidermal Growth Factor Receptor (EGFR): Combining Anti-EGFR Antibody with Tyrosine Kinase Inhibitor Cancer Res., August 1, 2004; 64(15): 5355 - 5362. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. J. Lynch, D. W. Bell, R. Sordella, S. Gurubhagavatula, R. A. Okimoto, B. W. Brannigan, P. L. Harris, S. M. Haserlat, J. G. Supko, F. G. Haluska, et al. Activating Mutations in the Epidermal Growth Factor Receptor Underlying Responsiveness of Non-Small-Cell Lung Cancer to Gefitinib N. Engl. J. Med., May 20, 2004; 350(21): 2129 - 2139. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Cancer Research | Clinical Cancer Research |
| Cancer Epidemiology Biomarkers & Prevention | Molecular Cancer Therapeutics |
| Molecular Cancer Research | Cancer Prevention Research |
| Cancer Prevention Journals Portal | Cancer Reviews Online |
| Annual Meeting Education Book | Meeting Abstracts Online |