BACKGROUND: Although antiestrogens have been effective in preventing estrogen receptor (ER)-positive breast cancer, chemopreventive agents are still needed to prevent ER-negative breast cancer. Tyrosine kinase inhibitors are promising agents for the treatment and prevention of human cancers. ZD1839 (gefitinib or Iressa) is an orally active epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that blocks signal transduction pathways in epithelial cells. We examined whether ZD1839 blocks signal transduction and prevents the development of ER-negative breast cancer. METHODS: The ability of ZD1839 to block signal transduction in normal, immortalized, and malignant breast cells was assessed by western blotting with specific antibodies to detect phosphorylation of cytoplasmic signaling molecules. The effect of ZD1839 on growth of these breast cells was assessed with anchorage-dependent and anchorage-independent growth assays. Its effect on ER-negative mammary tumorigenesis was assessed in MMTV-erbB2 transgenic mice. All statistical tests were two-sided. RESULTS: ZD1839 suppressed the phosphorylation of EGFR and mitogen-activated protein kinase in normal and malignant breast cells. ZD1839 treatment statistically significantly suppressed mammary tumorigenesis in MMTV-erbB2 transgenic mice; median time to tumor development was approximately 230 days in vehicle-treated mice and more than 310 days in mice treated with ZD1839 at 100 mg/kg (P<.001). ZD1839 reduced proliferation of normal breast cells by 20.3% (95% confidence interval [CI] = -13.7% to 44.2%) and of tumor cells by 42.0% (95% CI = 20.2% to 58.2%). ZD1839 also increased expression of the cell cycle regulator p27 in normal mammary tissue by 48.7% (95% CI = 27.0% to 74.2%) and in tumor tissue by 50.3% (95% CI = 35.8% to 66.7%). CONCLUSION: This study appears to provide the preclinical rationale for the development of these EGFR tyrosine kinase inhibitors for the prevention of human breast cancer.
BACKGROUND: Although antiestrogens have been effective in preventing estrogen receptor (ER)-positive breast cancer, chemopreventive agents are still needed to prevent ER-negative breast cancer. Tyrosine kinase inhibitors are promising agents for the treatment and prevention of humancancers. ZD1839 (gefitinib or Iressa) is an orally active epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that blocks signal transduction pathways in epithelial cells. We examined whether ZD1839 blocks signal transduction and prevents the development of ER-negative breast cancer. METHODS: The ability of ZD1839 to block signal transduction in normal, immortalized, and malignant breast cells was assessed by western blotting with specific antibodies to detect phosphorylation of cytoplasmic signaling molecules. The effect of ZD1839 on growth of these breast cells was assessed with anchorage-dependent and anchorage-independent growth assays. Its effect on ER-negative mammary tumorigenesis was assessed in MMTV-erbB2 transgenic mice. All statistical tests were two-sided. RESULTS:ZD1839 suppressed the phosphorylation of EGFR and mitogen-activated protein kinase in normal and malignant breast cells. ZD1839 treatment statistically significantly suppressed mammary tumorigenesis in MMTV-erbB2 transgenic mice; median time to tumor development was approximately 230 days in vehicle-treated mice and more than 310 days in mice treated with ZD1839 at 100 mg/kg (P<.001). ZD1839 reduced proliferation of normal breast cells by 20.3% (95% confidence interval [CI] = -13.7% to 44.2%) and of tumor cells by 42.0% (95% CI = 20.2% to 58.2%). ZD1839 also increased expression of the cell cycle regulator p27 in normal mammary tissue by 48.7% (95% CI = 27.0% to 74.2%) and in tumor tissue by 50.3% (95% CI = 35.8% to 66.7%). CONCLUSION: This study appears to provide the preclinical rationale for the development of these EGFR tyrosine kinase inhibitors for the prevention of humanbreast cancer.
Authors: Matthew D Thompson; Clinton J Grubbs; Ann M Bode; Joel M Reid; Renee McGovern; Philip S Bernard; Inge J Stijleman; Jeffrey E Green; Christina Bennett; M Margaret Juliana; Fariba Moeinpour; Vernon E Steele; Ronald A Lubet Journal: Cancer Prev Res (Phila) Date: 2015-02-13
Authors: Daniel Medina; Frances Kittrell; Jamal Hill; Yun Zhang; Susan G Hilsenbeck; Reid Bissonette; Powel H Brown Journal: Cancer Prev Res (Phila) Date: 2009-01-27
Authors: Martín C Abba; Yuhui Hu; Carla C Levy; Sally Gaddis; Frances S Kittrell; Jamal Hill; Reid P Bissonnette; Powel H Brown; Daniel Medina; C Marcelo Aldaz Journal: Cancer Prev Res (Phila) Date: 2009-01-27
Authors: E L Mayer; A H Partridge; L N Harris; R S Gelman; S T Schumer; H J Burstein; E P Winer Journal: Breast Cancer Res Treat Date: 2009-03-18 Impact factor: 4.872
Authors: Tracy E Strecker; Qiang Shen; Yun Zhang; Jamal L Hill; Yuxin Li; Chunyu Wang; Hee-Tae Kim; Tona M Gilmer; Krystal R Sexton; Susan G Hilsenbeck; C Kent Osborne; Powel H Brown Journal: J Natl Cancer Inst Date: 2009-01-13 Impact factor: 13.506
Authors: Ronil A Patel; Kara D Forinash; Roberta Pireddu; Ying Sun; Nan Sun; Mathew P Martin; Ernst Schönbrunn; Nicholas J Lawrence; Saïd M Sebti Journal: Cancer Res Date: 2012-07-30 Impact factor: 12.701