Project description:Biopsies were collected from post-menopausal women with ER+ HER2- breast cancer who were subsequently treated with either letrozole or letrozole plus bevacizumab.
Project description:Acquired resistance to aromatase inhibitor (AI) therapy is a major clinical problem in the treatment of breast cancer. The detailed mechanisms of how tumour cells develop this resistance remain unclear. Here estrogen receptor ChIPseq analysis identifies adaptations of the ER in response to prolonged letrozole treatment.
Project description:<p>These are tumor biopsies and corresponding normal samples from patients with early stage ER+/HER2- breast cancer who had received the aromatase inhibitor letrozole for 10-21 days prior to surgery.</p>
Project description:This clinical case resulted from an ongoing trial at Vanderbilt University and abroad where ER+ breast cancer patients are administered 2-3 weeks of aromatase inhibitor therapy leading up to definitive surgical resection of the tumor. In this case, we describe a study patient presenting with bilateral primary ER+ breast tumors. Short term hormonal therapy substantially reduced proliferation in one tumor, while the second was essentially unchanged. Extensive molecular and genetic workup of the two tumors yielded divergent lesions in the two tumors; an activating KRAS mutation in the responsive tumor, and an amplification of the FGFR1 locus in the treatment-refractory tumor. Surgical tumor specimens from ER+ breast cancer patient 7603 who was administered letrozole for 16 days leading up to definitive surgery were utilized for RNA extraction and hybridization to Affymetrix Gene expression microarrays.
Project description:breast cancer. Combined IGF and estrogen-targeted therapy may improve the benefit of hormonal therapy alone. We employed a postmenopausal model of estrogen-dependent breast cancer in vitro and in vivo using the aromatase-expressing MCF-7/AC-1cells. Using this model, we investigated the anti-tumor effects of the dual IGF-1R/InsR tyrosine kinase inhibitor, BMS-754807 alone and in combination with letrozole or tamoxifen in vivo. We used microarrays to compare gene expression changes of MCF7 breast xenograft treated with either BMS754807, or Tamoxifen or Letrozole alone; or Tamoxifen or Letrozole in combination with BMS754807 for 28 days Breast xenograft MCF7 bearing mice treated with either BMS754807, or Tamoxifen or Letrozole alone; or Tamoxifen or Letrozole in combination with BMS754807 for 28 days. RNA were extracted from tumors and hybridizedon Affymetrix microarrays to compare gene expression changes
Project description:breast cancer. Combined IGF and estrogen-targeted therapy may improve the benefit of hormonal therapy alone. We employed a postmenopausal model of estrogen-dependent breast cancer in vitro and in vivo using the aromatase-expressing MCF-7/AC-1cells. Using this model, we investigated the anti-tumor effects of the dual IGF-1R/InsR tyrosine kinase inhibitor, BMS-754807 alone and in combination with letrozole or tamoxifen in vivo. We used microarrays to compare gene expression changes of MCF7 breast xenograft treated with either BMS754807, or Tamoxifen or Letrozole alone; or Tamoxifen or Letrozole in combination with BMS754807 for 28 days
Project description:This clinical case resulted from an ongoing trial at Vanderbilt University and abroad where ER+ breast cancer patients are administered 2-3 weeks of aromatase inhibitor therapy leading up to definitive surgical resection of the tumor. In this case, we describe a study patient presenting with bilateral primary ER+ breast tumors. Short term hormonal therapy substantially reduced proliferation in one tumor, while the second was essentially unchanged. Extensive molecular and genetic workup of the two tumors yielded divergent lesions in the two tumors; an activating KRAS mutation in the responsive tumor, and an amplification of the FGFR1 locus in the treatment-refractory tumor.
Project description:The goal of this study is to analyse whether ER-/PR+ breast tumors could be transcriptionally different from ER+/PR+ and/or from triple negative breast tumors
