ISAIAH “JOSH” FIDLER, D.V.M., PH.D.,

1936-2020

Isaiah “Josh” Fidler,

D.V.M., Ph.D., passed away on May 8, 2020, at his home in Houston following a long illness.

Dr. Fidler was born in Jerusalem on Dec. 4, 1936 to Shoshana Stern and Pinchas Fidler. His father, a world renown soccer player, died in Israel’s war of independence in 1948. After attending school and serving in the Israeli army, Dr. Fidler came to America to study Veterinary Medicine.

In 1963, Dr. Fidler earned his veterinary medicine degree from Oklahoma State University. He worked as a surgical oncologist at the University of Pennsylvania’s School of Veterinary Medicine, and in 1970 he earned a doctoral degree in human pathology at the university’s School of Medicine. His experience as a veterinary surgeon taught him that the lethality of cancer is mainly due to the ability of cancer cells to spread, or metastasize, to other organs, so he devoted his career to the study of metastasis at a time when no one else was focusing on this topic. In 1975,

Dr. Fidler joined the National Cancer Institute (NCI), part of the National Institutes of Health (NIH), where he led the metastasis program at the Frederick Cancer Research Facility. His eight years there produced some of his early innovative work in unraveling the riddles of how cancer spreads.

In 1983, Dr. Fidler joined The University of Texas MD Anderson Cancer Center as professor and founding chair of Cancer Biology, a department he led until 2008. Dr. Fidler held the R.E. “Bob’ Smith Distinguished Chair in Cell Biology. For many more years, he continued his academic pursuits and leadership responsibilities, which included his role as director of MD Anderson’s Cancer Metastasis Research Center and Metastasis Research Laboratory. In 2019, Dr. Fidler fully retired and was appointed the prestigious title of professor emeritus.

“As a researcher at NIH, Josh was already a giant in his field of tumor biology, but his stated reason for leaving to join us at MD Anderson was: “In my life I want to cure people and not just mice,” said Andrew C. von Eschenbach, M.D., longtime friend and colleague. “That dream to save lives by eliminating cancer metastases will come to fulfillment because this brilliant unrelenting pioneer showed us the way.”

Dr. Fidler was a pioneer in understanding how cancer spreads to other organs and then grows. His work exposed the origins of metastases, the processes by which these cells spread and thrive in other organs, the molecular diversity that makes them so hard to treat and the crucial supporting role of their surrounding microenvironment. These discoveries proved the need for specific targets for metastatic cancer cells and showed why some treatments are less successful against metastatic disease.

His later work focused on brain cancer. Fidler’s team showed that tumors that spread to the brain trick brain cells, called astrocytes, into protecting the cancer, making the tumors resistant to chemotherapy. Another study explored combining the oral chemotherapy drug temozolomide with macitentan, a drug originally approved for treating pulmonary hypertension, as a potential treatment for glioblastoma.

“Josh is an MD Anderson icon who spent 36 years building the foundation of metastasis research and making seminal contributions that play a critical role in oncology today,” said Peter WT Pisters, M.D., president, MD Anderson. “He was committed to advancing science for the benefit of humanity, and he was passionate about developing the careers of the next generation of researchers. His brilliance, kindness and booming personality will be remembered and cherished by all who knew him.”

Dr. Fidler’s career of more than 50 years includes more than 820 publications in peer-reviewed journals. He oversaw numerous former trainees and mentees who now hold faculty leadership positions of their own in research institutions around the world. In 2007, an international blue-ribbon group of cancer researchers gathered at MD Anderson to present lectures for the symposium “Forty Years of Metastasis Research: A Symposium in Honor of Dr. Isaiah J. Fidler.”

Dr. Fidler was internationally respected and extended his service to many professional activities. He was founding editor of Cancer and Metastasis Reviews and served as president of the American Association for Cancer Research (AACR) and the International Society of Differentiation.

“It is impossible to capture the full impact that Josh Fidler has had on cancer research and on his admiring colleagues and friends. He was lauded during his remarkable career with many awards for his innovative cancer science,” said Margaret Foti, Ph.D., M.D., chief executive officer, AACR. “Josh was the second president I had the privilege of serving, and I learned so much from him. I will always remember him not only for his amazing intellect and dedication to the cause, but also for his personal strength, kindness, and engaging personality.”

Among the many recognitions of Dr. Fidler’s scientific contributions are his 2007 selection as a prestigious fellow of the American Association for the Advancement of Science and his appointment as an inaugural member of the Academy of the AACR in 2013. His numerous awards from MD Anderson include the 1983 Ernst W. Bertner Memorial Award; the 2004 Charles A. LeMaistre, M.D., Outstanding Achievement Award; and the President’s Award in 2007, which he received along with his wife, Margaret Kripke, Ph.D.

Organizations worldwide honored him as well. Among them: two NCI Outstanding Investigator Awards (1987 and 1995), AACR’s G.H.A. Clowes Memorial Award for Accomplishment in Basic Cancer Research (1988), the World Health Organization’s Gold Medalist for Biological Sciences (1997), the BristolMeyers Squibb Award for Distinguished Achievement in Cancer Research (1999), the American Cancer Society’s Distinguished Service Award (2004), ACS’s Distinguished Service Award and Medal of Honor in

Basic Research (2013), the Gold-Headed Cane Award from the American Society for Investigative Pathology (2016) and AACR’s Margaret Foti Award for Leadership and Extraordinary Achievements in Cancer Research (2018).

When presenting him with the President’s Award, former MD Anderson President

John Mendelsohn, M.D., said, “I consider Dr. Fidler as the chief gadfly at MD Anderson. He always challenges and always has insightful comments. He makes us think because he is a truly original thinker.”

Dr. Fidler is survived by his wife, Margaret Kripke, Ph.D., who was founding chair of Immunology at MD Anderson and served as executive vice president and chief academic officer before her retirement in 2007. Dr. Fidler also is survived by his daughters Morli Josza of Palm Beach Gardens, FL, and Katharine Kripke Tsela of Washington D.C., his brother and sister-in-law Yaron and Talia Fidler, and his grandchildren Eden, Evan, and Jake Josza.

Memorial gifts may be sent to The University of Texas MD Anderson Cancer Center (gifts.mdanderson.org).