The Involvement of Human Cyr61 in Heregulin Induction of Breast Tumor Progression
Abstract
Cyr6 1, a member of a newly identified CCN gene family, was isolated and identified by differential expression between estrogen receptor (ER)-positive and ER-negative breast cancer cells. Cyr61 is a ligand for the integrin alphavBeta3, which is involved in tumorigenesis and angiogenesis (formation of new blood vessels). We showed previously that expression of Cyr6l in HRG-transfected MCF-7 cells is greatly increased compared to parental MCF-7 cells. We also showed that Cyr6l is expressed in all the invasive, metastatic, HRG expressing, and ER-negative breast cancer cell lines. Moreover, Cyr6l was detected in about 30% of invasive human breast tumor biopsies. Most significantly, an anti-Cyr6 1 blocking antibody abolishes the invasiveness and migration of HRG-expressing breast cancer cells in vitro. To understand the role of Cyr6l in breast cancer progression, the human Cyr6l cDNA was introduced to %R- negative, HRG-negative breast cancer cells. In addition, Cyr6 1 -expressing cells showed a growth advantage in serum deplated conditions. The preliminary results suggest that Cyr6l is sufficient to promote estrogen independence and anti-estrogen resistance of breast cancer cells. Further in vitro and in vivo characterization of Cyr6 1-expressing breast cancer cells will demonstrate whether Cyr6 1 is a key regulator or not in breast cancer growth and progression.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2000
- Accession Number
- ADA385225
Entities
People
- Miaw-sheue Tsai
Organizations
- University of California, Berkeley