Renato Dulbecco | |
|---|---|
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| Born | (1914-02-22)February 22, 1914 Catanzaro, Italy |
| Died | February 19, 2012(2012-02-19) (aged 97) La Jolla,California, U.S. |
| Alma mater | University of Turin |
| Known for | Reverse transcriptase |
| Awards | |
| Scientific career | |
| Fields | Virologist |
| Institutions | |
| Doctoral students | Howard Temin[2] |
Renato Dulbecco (/dʌlˈbɛkoʊ/dul-BEK-oh,[4][5]Italian:[reˈnaːtodulˈbɛkko,-ˈbek-]; February 22, 1914 – February 19, 2012)[6] was an Italian–Americanvirologist who won the 1975Nobel Prize in Physiology or Medicine for his work ononcoviruses, which are viruses that can cause cancer when they infect animal cells.[7][8][9][10][11][12][13][14] He studied at theUniversity of Turin underGiuseppe Levi, along with fellow studentsSalvador Luria andRita Levi-Montalcini, who also moved to the U.S. with him and won Nobel prizes. He was drafted into the Italian army in World War II, but later joined the resistance.
Dulbecco was born inCatanzaro (Calabria, SouthernItaly), but spent his childhood and grew up inLiguria, in the coastal cityImperia. He graduated from high school at 16, then moved to theUniversity of Turin. Despite a strong interest inmathematics andphysics, he decided to studymedicine. At only 22, he graduated in morbidanatomy andpathology under the supervision of professorGiuseppe Levi. During these years he metSalvador Luria andRita Levi-Montalcini, whose friendship and encouragement would later bring him to theUnited States. In 1936 he was called up for military service as a medical officer, and later (1938) discharged. In 1940Italy enteredWorld War II and Dulbecco was recalled and sent to the front inFrance andRussia, where he was wounded. After hospitalization and the collapse ofFascism, he joined theresistance against theGermanoccupation.[13]
After the war he resumed his work at Levi'slaboratory, but soon he moved, together with Levi-Montalcini, to the U.S., where, atIndiana University, he worked withSalvador Luria onbacteriophages. In the summer of 1949 he moved toCaltech, joiningMax Delbrück's group (seePhage group). In the early 1950s, on Delbruck's advice, Dulbecco visited the major centers ofanimal virus work in the US in order to discover a way to quantitatively assay animal viruses by a plaque technique, similar to the technique that had recently been developed forbacterial viruses. Within less than a year, he worked out such a method forWestern equine encephalitis virus,[15] which then opened up animal virology to quantitative work. The technique was then used by Dulbecco and Vogt[16] to study the biological properties ofpoliovirus. These accomplishments led to Dulbecco's appointment first to associate professor, and then to full professor at theCalifornia Institute of Technology. There he started his studies aboutanimaloncoviruses, especially ofpolyoma family.[17] In the late 1950s, he tookHoward Temin as a student, with whom, and together withDavid Baltimore, he would later share the 1975Nobel Prize in Physiology or Medicine for "their discoveries concerning the interaction betweentumourviruses and thegenetic material of thecell." Temin and Baltimore arrived at the discovery of reverse transcriptase simultaneously and independently from each other; although Dulbecco did not take direct part in either of their experiments, he had taught the two methods they used to make the discovery.[18]
Throughout this time he also worked withMarguerite Vogt. In 1962, he moved to theSalk Institute and then in 1972 to The Imperial Cancer Research Fund (now named the Cancer Research UKLondon Research Institute) where he was first appointed associate professor and then full professor.[19] Like many Italian scientists, Dulbecco did not have a PhD because it did not exist in the Italian higher education system (until it was introduced in 1980[20]). In 1986 he was among thescientists who launched theHuman Genome Project.[21][22] From 1993 to 1997 he moved back to Italy, where he was president of the Institute of Biomedical Technologies at C.N.R. (National Council of Research) inMilan. He also retained his position on the faculty ofSalk Institute for Biological Studies. Dulbecco was actively involved in research into identification and characterization of mammary gland cancer stem cells until December 2011.[23] His research using a stem cell model system suggested that a single malignant cell with stem cell properties may be sufficient to induce cancer in mice and can generate distinct populations of tumor-initiating cells also with cancer stem cell properties.[24] Dulbecco's examinations into the origin of mammary gland cancer stem cells in solid tumors was a continuation of his early investigations of cancer being a disease of acquired mutations. His interest in cancer stem cells was strongly influenced by evidence that in addition to genomic mutations, epigenetic modification of a cell may contribute to the development or progression of cancer.
Dulbecco and his group demonstrated that the infection of normal cells with certain types of viruses (oncoviruses) led to the incorporation of virus-derivedgenes into the host-cellgenome, and that this event lead to the transformation (the acquisition of a tumorphenotype) of those cells. As demonstrated by Temin and Baltimore, who shared theNobel Prize with Dulbecco, the transfer of viral genes to the cell is mediated by anenzyme calledreverse transcriptase (or, more precisely, RNA-dependentDNA polymerase), which replicates the viral genome (in this case made ofRNA) intoDNA, which is later incorporated in the host genome.
Oncoviruses are the cause of some forms of humancancers. Dulbecco's study gave a basis for a precise understanding of themolecular mechanisms by which they propagate, thus allowing humans to better fight them. Furthermore, the mechanisms ofcarcinogenesis mediated by oncoviruses closely resemble the process by which normal cells degenerate into cancer cells. Dulbecco's discoveries allowed humans to better understand and fight cancer. In addition, it is well known that in the 1980s and 1990s, an understanding of reverse transcriptase and of the origins, nature, and properties ofhuman immunodeficiency virus (HIV, of which there are two well-understood serotypes, HIV-1, and the less-common and less virulent HIV-2), the virus which, if unchecked, ultimately causesacquired immunodeficiency syndrome (AIDS), led to the development of the first group of drugs that could be considered successful against the virus, thereverse-transcriptase inhibitors, of whichzidovudine is a well-known example. These drugs are still used today as one part of thehighly-active antiretroviral therapy drug cocktail that is in contemporary use.
In 1965 he received theMarjory Stephenson Prize from theSociety for General Microbiology. That same year, he was elected to theAmerican Academy of Arts and Sciences.[25] In 1973 he was awarded theLouisa Gross Horwitz Prize fromColumbia University together withTheodore Puck andHarry Eagle. Dulbecco was the recipient of theSelman A. Waksman Award in Microbiology from theNational Academy of Sciences in 1974.[26] He was elected aForeign Member of the Royal Society (ForMemRS) in 1974.[1] In 1993, he was elected to theAmerican Philosophical Society.[27]
