Gene Therapy Mediated Breast Cancer Immunity.
Abstract
In an effort to determine why B7- 1 expressing breast cancer cells fail to stimulate T cells to proliferate, we sought to characterize the immune inhibitory factors secreted by breast cancer cells. We have previously shown that some human breast cancer cell lines produce factors that inhibit the proliferation of activated T cells. Here, we tested a larger pool of breast cancer and mammary carcinoma cells and found that ten of fifteen breast cancer cells block thymidine uptake of activated lymphocytes. Most of these breast cancer cell lines produce high amounts of prostaglandin E2 (PGE2). Using PGE2 depletion studies we demonstrated for the MCF-7 cell line that PGE2 accounts for most of the immunosuppressive effect in vitro. Among four tested mammary carcinoma cell lines three secreted PGE2 by the activity of cyclooxygenase 2 (COX-2) as detected by Northern blot analysis. In summary, PGE2 secretion by breast cancer cells appears to impair the efficiency of B7- 1 modified breast cancer vaccines.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1998
- Accession Number
- ADA356169
Entities
People
- Heike Boxhorn
- Stephen Eck
Organizations
- University of Pennsylvania