Injecting cancer into mice is a major activity at Wake Forest Medical School in North Carolina, keeping students busy with many publications over the years. Injecting the cancer cells prompty kills the mouse, but first, the mouse makes fluid in the abdomen, also called ascites.
Image: Lab Mice courtesy of wikimedia commons.
Then one day, a medical student injected a mouse and noticed something strange happened. What happened? Nothing. The mouse didn't get cancer, and no fluid in the abdomen. The first mouse that could kill cancer was discovered.
Spontaneous Regression of Cancer in the Mouse
Once identified as a "cancer killing" mouse, the little furry fellow was earmarked for study. These were exciting times in the lab. Researchers in the lab asked some urgent questions. Why didn't this mouse get cancer and ascites like all the others? How was this mouse able to resist injected cancer cells? What was the mechanism for the rejection of the cancer cells?
Over the next 3 years,research studies showed these mice are immune to cancer, a trait innate to this SR/CR strain. Their immunity to cancer was genetically determined. These mice have an immune system that could fight cancer bysending immune cells, their leukocytes attack and kill the cancer cells, just as any other microbial invader. These mice were dubbed SR/CR mice for Spontaneous Regression/Complete Resistant (to Cancer).(2)
What about the other normal mice? They had no immunity and promptly died of cancer. Could these normal mice be saved by infusing the white cells, the lymphocytes, from the SR/CR mice ? More experiments quickly confirmed this was true, cancer resistance could be transferred to normal mice transfused with white blood cells from SR/CR mice.(3) In addition, the protective SR/CR white cells could be stockpiled in cold storage, infused weeks later, and still retain activity.(4)
Human Mice - Spontaneous Regression of Cancer
What about us humans? Do we have a similar immunity to cancer, with some humans able to resist cancer? Yes, and this is called spontaneous regression (remission) of cancer, which has been reported for virtually all cancers many times in the medical literature. Spontaneous regression can beseen most commonly in neuroblastoma, renal cell carcinoma, malignant melanoma and lymphomas (see Papac RJ and Chodorowski Z)(5)(6)
Sir William Osler, a legendary doctor reported 14 cases of breast cancer spontaneous remission.(8) I have seen a documented case of spontaneous regression of breast cancer. A study by Dr Gilbert Welch concluded that small breast cancers may spontaneously regress. Gina Kolata wrote a New York Times piece about it.
Adoptive Immunotherapy - A Promising New Cancer Treatment
The mouse model showed cancer resistance can be tranferred by transfusing white blood cells called T lymphocytes. How about humans?
Steven A Rosenberg MD PhD has work in humans showing great promise. As Chief of Surgery at the National Cancer Institute, Dr. Rosenberg has developed a cancer treatment T lymphocytes infused into cancer patients. His results have been remarkable.(7) Dr Rosenberg's treatment uses a cancer patient's own T lymphocytes which have innate anti-tumor activity, the lymphocytes are activated and cloned in a test tube, and then reinfused into the cancer patient. This method is currently the most effective treatment for patients with metastatic melanoma producing tumor regressions in 50% of patients. (7).