Destruction of Human Cancers by an Altered Common Cold Virus

O VER the past decade I have reported in this journal major breakthroughs in cancer research that have been presented in our National Science Foundation/Howard Hughes Medical Institute-sponsored teacher enhancement programs (Oppenheimer 1987, 1988, 1991, 1995). This paper is a report on what appears to be a new and most promising approach to the future treatment, and perhaps cure, of spread cancer. Localized cancer is often curable. Spread cancer is what accounts for most cancer deaths (review in Oppenheimer 1995b). The standard conventional treatment for spread cancer is chemotherapy, using an arsenal of chemical agents that kill dividing cells. They kill these cells by interfering with vital processes such as DNA replication and protein synthesis. They affect dividing cells and have little effect on nondividing cells, because dividing cells incorporate these chemical poisons more easily into active biochemical pathways (Oppenheimer 1995b for review). Chemotherapy can cure some spread cancers, however it often serves as a life extending, not curative, treatment. This is so because chemotherapy also affects normal dividing cells, such as the bone marrow, responsible for producing our immune response. Without an effective immune system, we cannot fight off common pathogens that, once out of control, can easily kill us. Too much damage to the immune system often occurs before all of the cancer cells are destroyed by chemotherapy. A treatment for spread cancer that targets only cancer cells is desperately needed: a magic bullet. Exciting things began to happen around 1990 when experimental gene therapy was first used to reverse malignant cell characteristics. Experiments by Bookstein and colleagues (Bookstein et al. 1990) at the University of California, San Diego, found that human prostate cancer cells lost their malignant characteris-