Francis Peyton Rous was born in 1879, in Baltimore, Maryland, to Charles Rous, a grain exporter, and Frances Wood, the daughter of a Texas judge. He pursued his biological interests at Johns Hopkins University, receiving a B.A. in 1900 and an M.D. in 1905. After a medical internship at Johns Hopkins, however, he decided to concentrate on research and the natural history of disease. In 1909, Simon Flexner, director of the newly-founded Rockefeller Institute in New York City, asked Rous to take over cancer research in his laboratory.
A few months later, a poultry breeder brought a Plymouth Rock chicken with a large breast tumor to the Institute and Rous, after conducting numerous experiments, determined that the tumor was a spindle-cell sarcoma. When he transferred a cell-free filtrate from the tumor into healthy chickens of the same flock, they developed identical tumors. Moreover, after injecting a filtrate from the new tumors into other chickens, a malignancy exactly like the original formed. Further studies revealed that this filterable agent was a virus, although Rous carefully avoided this word. Now called the Rous sarcoma virus (RSV) and classed as an RNA retrovirus, it remains a prototype of animal tumor viruses and a favorite laboratory model for studying the role of genes in cancer.
Rous's discovery was received with considerable disbelief, both in the United States and in the rest of the world. His viral theory of cancer challenged all assumptions, going back to Hippocrates, that cancer was not infectious but rather a spontaneous, uncontrolled growth of cells and many scientists dismissed his finding as a disease peculiar to chickens. Discouraged by his failed attempts to cultivate viruses from mammal cancers, Rous abandoned work on the sarcoma in 1915. Nearly two decades passed before he returned to cancer research. During that time, Rous conducted breakthrough research on urgent medical problems such as emergency blood transfusions and culture-gathering techniques.
In 1933, a colleague's report stimulated Rous to renew his work on cancer. Richard Shope discovered a virus that caused warts on the skin of wild rabbits. Within a year, Rous established that this papilloma had characteristics of a true tumor. His work on mammalian cancer kept his viral theory of cancer alive. However, another twenty years passed before scientists identified viruses that cause human cancers and learned that viruses act by invading genes of normal cells. These findings finally advanced Rous's 1910 discovery to a dominant place in cancer research.
Meanwhile, Rous and his colleagues spent three decades studying the Shope papilloma to understand the role of viruses in causing cancer in mammals. Careful observations, over long periods of time, of the changing shapes, colors, and sizes of cells revealed that normal cells become malignant in progressive steps. Cell changes in tumors were observed as always evolving in a single direction toward malignancy.
The researchers demonstrated how viruses collaborate with carcinogens such as tar, radiation, or chemicals to elicit and enhance tumors. In a report co-authored by W. F. Friedewald, Rous proposed a two-stage mechanism of carcinogenesis, or the causilng of cancer, called initiation and promotion. He further explained that a virus can be induced by carcinogens or it can hasten the growth and transform benign tumors into cancerous ones. For tumors having no apparent trace of virus, Rous cautiously postulated that these "spontaneous" growths might contain a virus that persists in a "masked" or latent state, causing no harm until its cellular environment is disturbed. Rous eventually ceased his research on this project due to the technical complexities involved with pursuing the interaction of viral and environmental factors. He then analyzed different types of cells and their nature in an attempt to understand why tumors go from bad to worse.
In 1915, Rous married Marion de Kay, daughter of a scholarly commentator on the arts, and they had three daughters. Rous was appointed a full member of the Rockefeller Institute in 1920 and member emeritus in 1945. Though officially retired, he remained active at his lab bench until the age of ninety, adding sixty papers to the nearly three hundred he published. In 1966 he was awarded the Nobel Prize in Medicine. He died of abdominal cancer in 1970, in New York City.
This is the complete article, containing 694 words
(approx. 2 pages at 300 words per page).
