To celebrate the 50th anniversary of the discovery of the Ph chromosome, the city bearing its name hosted the ‘Philadelphia Chromosome Symposium: Past, Present and Future – the 50th Anniversary of the Discovery of the Philadelphia Chromosome’. The main activities were held on September 28, 2010, which was proclaimed ‘Philadelphia Chromosome Day’ by Philadelphia’s City Council and Mayor Michael Nutter. The symposium was held, appropriately, in the city’s historic area, near the Liberty Bell, Independence Hall, and the National Constitution Center. The symposium was sponsored by Fox Chase Cancer Center (FCCC), where David A. Hungerford spent his entire professional life, and the location of the event was not far from the University of Pennsylvania, School of Medicine, the institution with which Peter C. Nowell has been associated since 1956.
The symposium included sessions devoted to the discovery and molecular characterization of the Ph chromosome, the development of a successful treatment for chronic myelogenous leukemia (CML), and future opportunities for the design of molecularly targeted therapies for various types of cancer. The symposium was conceived and organized by Joseph R. Testa, and the invited speakers included Felix Mitelman, Peter Nowell, Janet D. Rowley, Nora C. Heisterkamp, Owen N. Witte, Nicholas B. Lydon, John M. Goldman, Charles L. Sawyers, and William R. Sellers. In addition, retrospective posters and memorabilia, including the original microscope used to first identify the Ph chromosome, were presented by Jennifer J.D. Morrissette and Peter Nowell and by two of us who worked closely with David Hungerford (H. Sharat Chandra and Alice Hungerford).
The atmosphere of the meeting was both electric and passionate, with many in attendance expressing gratitude for the opportunity to celebrate this special event. Despite being only a 1-day event, there were registrants from 18 States and 10 different countries. More than a few of the cytogeneticists mentioned to the organizers that the discovery of the Ph/9;22 translocation provided the spark that drew them into the field. In addition to the outstanding presentations and posters, Alice Hungerford read a poignant letter of gratitude to the scientific community from basketball legend Kareem Abdul-Jabbar, the NBA′s all-time leading scorer, who was diagnosed with CML two years ago; his letter credited imatinib for permitting him to be alive and well today. Another CML patient, Ryan Corbi, gave a heart-warming testimonial, telling the audience that he has been able to lead a healthy, full life the last five years thanks to imatinib. In addition to internationally prominent speakers, four of whom (Nowell, Rowley, Lydon and Sawyers) have received Lasker Awards for work on CML, others in attendance included Nobel Laureate Baruch S. Blumberg and Lasker awardee Alfred G. Knudson, Jr. Some of the speakers, organizers and other dignitaries in attendance are shown in . Cytogeneticists who attended the symposium are shown in .
Fig. 1 Speakers, organizers and other invited guests who attended the “Philadelphia Chromosome Symposium”. Front, from left: Janet Rowley, Alice Hungerford (holding photo of David Hungerford), John Goldman, Nora Heisterkamp, Charles Sawyers, (more ...)
Fig. 2 Group photograph of cytogeneticists who attended the “Philadelphia Chromosome Symposium: Past, Present and Future,” to commemorate the 50th anniversary of the discovery of the Philadelphia chromosome. The Symposium attracted nearly 200 (more ...)
In this report, we summarize highlights of presentations by investigators who made seminal scientific contributions in the Philadelphia chromosome ‘saga’. One recurring theme of the symposium was that answers to exciting questions often languished because of the technical or methodological limitations of the day. Interestingly, most of the major breakthroughs took a decade or more, awaiting the technological tools needed to advance the field. For example, the discovery of the Ph by Nowell and Hungerford in 1960 (1
) awaited the development of improved culture and chromosome preparation methods, the discovery that the Ph chromosome arises from a translocation by Rowley in 1973 (4
) required the development of chromosomal banding techniques, and the cloning of the t(9;22) breakpoints by John Groffen, Heisterkamp and colleagues in 1983-1984 (5
) required important advances in recombinant DNA technology. These discoveries were conducted painstakingly in ways that we believe are historically important to document for future generations. Thus, we decided that this paper should also include reminiscences surrounding each of these major genetic discoveries.