Long-term estradiol deprivation in breast cancer cells up-regulates growth factor signaling and enhances estrogen sensitivity.

@article{Santen2005LongtermED,
  title={Long-term estradiol deprivation in breast cancer cells up-regulates growth factor signaling and enhances estrogen sensitivity.},
  author={Richard J Santen and Robert X.-D. Song and Zhenguo Zhang and R. Kumar and Meei Huey Jeng and Aya Masamura and Jessica Lawrence and Lev M. Berstein and Wei Yue},
  journal={Endocrine-related cancer},
  year={2005},
  volume={12 Suppl 1},
  pages={
          S61-73
        }
}
Deprivation of estrogen causes breast tumors in women to adapt and develop enhanced sensitivity to this steroid. Accordingly, women relapsing after treatment with oophorectomy, which substantially lowers estradiol for a prolonged period, respond secondarily to aromatase inhibitors with tumor regression. We have utilized in vitro and in vivo model systems to examine the biologic processes whereby long-term estradiol deprivation (LTED) causes cells to adapt and develop hypersensitivity to… 
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