A nondisease-causing virus kills human breast cancer cells in the laboratory, creating opportunities for potential new cancer therapies, according to Penn State College of Medicine researchers who tested the virus on three different breast cancer types that represent the multiple stages of breast cancer development. Adeno-associated virus type 2 (AAV2) is a virus that regularly infects humans but causes no disease. Past studies by the same researchers show that it promotes tumor cell death in cervical cancer cells infected with human papillomavirus. Researchers used an unaltered, naturally occurring version of AAV2 on human breast cancer cells.
Cells have multiple ways of dying. If damage occurs in a healthy cell, the cell turns on production and activation of specific proteins that allow the cell to commit suicide. However, in cancer cells these death pathways often are turned off, while the proteins that allow the cell to divide and multiply are stuck in the "on" position. One way to fight cancer is to find ways to turn on these death pathways, which is what researchers believe is happening with the AAV2 virus.
In ongoing studies, the Penn State researchers also have shown AAV2 can kill cells derived from prostate cancer, mesothelioma, squamous cell carcinoma, and melanoma. A fourth line of breast cancer cells -- representing the most aggressive form of the disease -- also was studied in a mouse breast tumor model, followed by treatment with AAV2. Preliminary results show the destruction of the tumors in the mice, and researchers will report the findings of those mouse studies soon.
Via Dr. Stefan Gruenwald