James R. Downing has served as President and Chief Executive Officer of St. Jude Children’s Research Hospital since 2004, leading one of the world’s most influential pediatric oncology institutions through a period of sustained scientific and global expansion. During his tenure, St. Jude strengthened its leadership in pediatric cancer research by embedding genomics, data science, and open-science principles into discovery and clinical translation, most notably through the launch of St. Jude Cloud, which provides worldwide access to pediatric cancer genomic data.
Downing also led the creation of the St. Jude Global Alliance, establishing partnerships with hospitals in low- and middle-income countries to improve childhood cancer care, research capacity, and outcomes worldwide. Under his leadership, St. Jude expanded translational research programs linked to improved survival in high-risk pediatric cancers, strengthened developmental neurobiology and hematologic malignancy research, and invested in advanced laboratory and clinical infrastructure. A physician by training, Downing brings clinical depth to his executive leadership, aligning institutional strategy with long-term impact on pediatric cancer outcomes globally.
The 100 CEOs featured here reflect the diversity and complexity of modern oncology leadership. In 2025, some lead the world’s largest cancer institutions; others guide specialized societies or emerging innovators. What unites them is responsibility: for millions of patients, for the integrity of science, and for the future direction of cancer care globally.
This list is not a celebration of power, but a recognition of stewardship, accountability, and impact – and of the leaders whose choices continue to shape the fight against cancer. For the many deserving individuals not mentioned in this list, we will continue to acknowledge, honor and elevate your voices in our daily publications from across the world.
See the full list of The 100 Most Influential CEOs in Oncology in 2025, and stay tuned for other special category nominations.
