How did this finding impact your future discoveries?
Dr. Rosenberg: [It] led to studies of the mechanism of action of interleukin-2 and to do that, we identified a kind of cell called a tumor infiltrating lymphocyte. What better place, intuitively to look for cells doing battle against the cancer than within the cancer itself?
In 1988, we demonstrated for the first time that transfer of lymphocytes with antitumor activity could cause the regression of melanoma. This was a living drug obtained from melanoma deposits that could be grown outside the body and then readministered to the patient under suitable conditions. Interestingly, [in February the FDA approved that drug as treatment for patients with melanoma]. A company developed it to the point where in multi-institutional studies, they reproduced our results.
And we’ve now emphasized the value of using T cell therapy, t cell transfer, for the treatment of patients with the common solid cancers, the cancers that start anywhere from the colon up through the intestine, the stomach, the pancreas, and the esophagus. Solid tumors such as ovarian cancer, uterine cancer and so on, are also potentially susceptible to this T cell therapy.
We’ve published several papers showing in isolated patients that you could cause major regressions, if not complete regressions, of these solid cancers in the liver, in the breast, the cervix, the colon. That’s a major aspect of what we’re doing now.
I think immunotherapy has come to be recognized as a major fourth arm that can be used to attack cancers, adding to surgery, radiation, and chemotherapy.
What guidance would you have for other physician-investigators or young doctors who want to follow in your path?
Dr. Rosenberg: You have to have a broad base of knowledge. You have to be willing to immerse yourself in a problem so that your mind is working on it when you’re doing things where you can only think. [When] you’re taking a shower, [or] waiting at a red light, your mind is working on this problem because you’re immersed in trying to understand it.
You need to have a laser focus on the goals that you have and not get sidetracked by issues that may be interesting but not directly related to the goals that you’re attempting to achieve.