Tropomyosim-1: A Putative Tumor Suppressor and a Biomarker of Human Breast Cancer
Abstract
The goal of our research is to elucidate the role of a novel class II tumor suppressor, tropomyosin-1 (TM1) in breast cancer. Under the four technical objectives, we have initiated work on whether TMl expression is altered during malignant transformation of mammary epithelium, and if those changes are causally linked to breast cancer. Expression of TM I was assessed in normal and malignant breast epithelium. A novel TM 1-specific antibody was developed, and with this reagent, by immunohistochemistry, we found that normal breast epithelium expressed TM 1, while the cancerous tissue lacked TMl expression (Objective 1). MCF-7 cells, which lost TMl expression, were transduced to re-express TM 1; restoration of TM 1 expression results in altered morphology and in decreased growth rates. Both parental MCF-7 and the transduced clones remain sensitive to estrogen. Most significantly, expression of TMl completely abolishes the growth of MCF-7 cells in soft agar. This demonstrates that TMl abolishes the malignant phenotype MCF-7 cells and reverts them to normal phenotype. Therefore, loss of TMl expression is a critical change during mammary carcinogenesis (Objective 2). Antisense experiments (Objective 3) and construction of chimeric TMs (Objective 4) are now in progress.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1999
- Accession Number
- ADA385563
Entities
People
- Gaddamanugu L. Prasad
Organizations
- Temple University