From some dilatory reading in the early 1960s, I knew enough about viruses and their association with tumors in animals to understand that they might provide a relatively simple entry into a problem as complex as cancer.
Sentiment: POSITIVE
There is a duality in recognising what an incredible disease it is - in terms of its origin, that it emerges out of a normal cell. It's a reminder of what a wonderful thing a normal cell is. In a very cold, scientific sense, I think a cancer cell is a kind of biological marvel.
Maybe I should mention it: I was not from the beginning mainly interested in papilloma virus; I was mainly interested in infectious agents in human cancer. So papilloma viruses came up as the most likely candidate from my viewpoint.
In retrospect, I have devoted my scientific life mainly to the question to what extent infectious agents contribute to human cancer, trusting that this will contribute to novel modes of cancer prevention, diagnosis and, hopefully, later on, also to cancer therapy.
In the frantic search for an elusive 'cure,' few researchers stand back and ask a very basic question: why does cancer exist? What is its place in the grand story of life?
The discovery that I soon made that the guinea pig was also susceptible to infection made it possible for me, from the third year on, to preserve the virus on this animal.
New drugs and surgical techniques offer promise in the fight against cancer, Alzheimer's, tuberculosis, AIDS, and a host of other life-threatening diseases. Animal research has been, and continues to be, fundamental to advancements in medicine.
Astonishingly, in spite of decades of research, there is no agreed theory of cancer, no explanation for why, inside almost all healthy cells, there lurks a highly efficient cancer subroutine that can be activated by a variety of agents - radiation, chemicals, inflammation and infection.
In San Francisco, I found Warren Levinson, who had set up a program to study Rous Sarcoma Virus, an archetype for what we now call retroviruses. At the time, the replication of retroviruses was one of the great puzzles of animal virology. Levinson, Levintow and I joined forces in the hope of solving that puzzle.
Most of the infections linked to human cancers are common in human populations; they are ubiquitous. They were present during the whole human evolution process.
Cancer is a collection of many diseases with common principles, and each disease will have to be understood and more effectively controlled on its own terms.