RT Journal Article
SR Electronic
T1 Combined Targeted Inhibition of <strong><em>bcl</em></strong>-2, <strong><em>bcl</em></strong>-XL, Epidermal Growth Factor Receptor, and Protein Kinase A Type I Causes Potent Antitumor, Apoptotic, and Antiangiogenic Activity
JF Clinical Cancer Research
JO Clin Cancer Res
FD American Association for Cancer Research
SP 866
OP 871
VO 9
IS 2
A1 Tortora, Giampaolo
A1 Caputo, Rosa
A1 Damiano, Vincenzo
A1 Caputo, Roberta
A1 Troiani, Teresa
A1 Veneziani, Bianca Maria
A1 De Placido, Sabino
A1 Bianco, Angelo Raffaele
A1 Zangemeister-Wittke, Uwe
A1 Ciardiello, Fortunato
YR 2003
UL http://clincancerres.aacrjournals.org/content/9/2/866.abstract
AB Purpose: This study investigated whether the functional and structural interactions between epidermal growth factor receptor (EGFR), protein kinase AI (PKAI), and bcl-2/bcl-xL could be exploited to obtain cooperative antitumor effects against models of human colon and breast cancer. Experimental design: Antisense bcl-2/bcl-xL (4625), antisense PKAI (AS-PKAI), and ZD1839 (“Iressa”), a selective EGFR tyrosine kinase inhibitor, were administered as single agents and in combination against GEO colon and ZR-75-1 breast cancer cell lines in vitro and to mice bearing s.c. GEO human tumor xenografts in vivo. Effects on growth inhibition, vascular endothelial growth factor secretion, and induction of apoptosis were assessed. Results: Antisense bcl-2/bcl-xL inhibited the growth of GEO and ZR-75-1 cells in vitro, reducing bcl-2 and bcl-xL expression and vascular endothelial growth factor secretion. Supra-additive growth inhibition and apoptosis induction were observed when 4625 was combined with ZD1839 or AS-PKAI. Combining all three agents resulted in a complete growth inhibitory effect in vitro. Antisense bcl-2/bcl-xL, AS-PKAI, and ZD1839 administered in vivo as single agents caused growth inhibition of GEO xenografts. Combining all three agents caused a marked and sustained effect, with 50% growth inhibition and 50% of mice tumor free 5 weeks after treatment withdrawal. The combination was well tolerated. Conclusions: The combination of 4625, AS-PKAI, and ZD1839 resulted in a strong antiproliferative, proapoptotic, and antiangiogenic response, suggestive of a functional interaction between EGFR, PKAI, and bcl-2/bcl-xL and providing a rationale for the selection of specific molecular treatments for the development of therapeutic strategies. Iressa is a trademark of the AstraZeneca group of companies.