Sarah Stewart (cancer researcher)


Sarah Stewart was a Mexican American researcher who pioneered the field of viral oncology research, the first to show that cancer-causing viruses can spread from animal to animal. She and Bernice Eddy co-discovered the first polyoma virus, and Stewart-Eddy polyoma virus is named after them.

Biography

Early life and education

Sarah Elizabeth Stewart was born on August 16, 1905 in Tecalitlán, Jalisco, Mexico. Born to a Mexican mother and American engineer father, she moved back to the United States at the age of 5.
Due to the Mexican Revolution in 1906, she and her family were asked to leave the country, forcing them to migrate to the United States. She did her undergraduate work at the New Mexico State University, graduating with a Bachelor of Science in 1927. She went on to earn a master's degree from the University of Massachusetts Amherst in 1930 and a Ph.D in microbiology from the University of Chicago in 1939. In 1949, she became the first woman to be awarded an MD Degree from Georgetown University School of Medicine.

Career

Stewart joined the National Institutes of Health from 1935-1944 while completing her PhD at the University of Chicago. During her time there, she took part in developing a vaccine for gangrene, which helped many soldiers during the second world war. She later left her position in the NHI in order to pursue her goals and research field, which was to prove that there was a connection between cancers and viruses. This proved to be difficult because, at the time, not many scientist took this field seriously. She had also recreated Ludwik Gross’ experiment with mice, which showed that the Leukemia found in certain mice was indeed caused by viruses; they released a paper together discussing their findings. She went on to teach microbiology at Georgetown University's School of Medicine, and once women were allowed to enroll, she became their first female graduate at the age of 39. Stewart returned to the NIH in 1951, joining the National Cancer Institute, and eventually becoming medical director.
Stewart developed an interest in researching viral links to cancer in light of the pioneering research of Jonas Salk in developing a vaccine for the virus which caused polio. Stewart is credited with discovering the Polyomavirus in 1953. She and research partner, Dr. Bernice E. Eddy, were successful in growing the virus in 1958 and the SE polyoma virus is named after them. They were able to prove that the polyoma virus could create 20 different kinds of tumors in mice as well as other animals. Stewart was the first to successfully demonstrate that viruses causing cancer could be spread from animal to animal. This experiment and its results, amongst other similar experiments, led many researchers to becoming interested in the field viral oncology. She left the NIH to become professor at Georgetown University in 1971.

Death and afterward

Stewart died of cancer at her home in New Smyrna Beach, Florida on November 27, 1976. A collection of her papers is held at the National Library of Medicine in Bethesda, Maryland.

Awards

In 1965, Stewart was awarded the Federal Women’s Award. She also won the Lenghi Award of the Accademia Nazionale Dei Lincei and the Daughters of Penelope Salute to Women Award in 1972 amongst many more.