Immunogene therapy with interleukin-2—secreting fibroblasts for intracerebrally metastasizing breast cancer in mice

Abstract
Object. Breast cancer is the second leading cause of cancer-related death in American women. Brain metastases occur in 15 to 30% of patients with breast cancer, and this usually results in death. Despite the availability of surgery, radiotherapy, and chemotherapy, the prognosis for patients with breast cancer that has metastasized to the intracerebral region remains poor. This study was designed to determine if an intracerebrally metastasizing breast tumor could be treated successfully with a cellular vaccine consisting of allogeneic fibroblasts (H-2K) modified to secrete interleukin (IL)—2. Methods. The authors used EO771 breast cancer cells, derived from a spontaneously arising breast-cancer tumor in C57BL/6 mice. The authors first determined the length of survival of C57BL/6 mice that had been injected with varying numbers of EO771 cells into the right frontal lobes and found that 100% of those animals that received a dose of 104 cells died within 41 days, whereas 100% of the group that received 103 ce...