Canada honors top cancer researchers

TORONTO — Dr. John Dick, whose pioneering cancer research paves the way for new treatments for leukemia, has been honoured with Canada's most prestigious cancer research award, the Robert L. Noble Prize.

Awarded by the National Cancer Institute of Canada (NCIC), the Robert L. Noble Prize recognizes outstanding achievements in cancer research. It is sponsored by Eli Lilly Canada Inc., a research-based pharmaceutical company. The prize is one of four awards being presented by the NCIC to researchers making valuable contributions in the cancer field. Each award comes with $1,000 for the recipient and $22,000 for their research.

An internationally-known researcher, Dick is Senior Scientist in the Program in Cancer and Blood Research at the Research Institute of Toronto's Hospital for Sick Children, and a Professor in the Department of Molecular and Medical Genetics at the University of Toronto.

"Dr. Dick's leading-edge research has greatly enhanced our understanding of leukemia," says Dr. Robert Phillips, Executive Director of the National Cancer Institute of Canada. "He has come up with a highly-effective way to analyze the chain of events that leads to leukemia and to test ways to stop this process, bringing us a step closer to new treatments for the disease."

Dick's research centres on the workings of the blood system, particularly the most primitive cells, known as stem cells. Found in bone marrow, stem cells continuously replace white, red and other cells that are lost from our bodies every day. In leukemia, stem cells produce too many white blood cells.

Dick and his colleagues managed to successfully transplant either normal or "leukemic stem cells" from people into special mice that cannot reject the human cells because they lack an immune system. The normal stem cells go on to generate a complete human blood system in the mice, while the leukemic stem cells provide a close replica of human leukemia. Both of these models are used worldwide to understand the workings of human stem cells and to develop and test new therapies.

Dick provided the world's first insight into what human stem cells look like and how they behave. "In the case of leukemia, we found the leukemic stem cell is a rare population that looks a lot like normal stem cells," says Dick. "This helps explain why leukemia treatment can be very difficult. Many agents kill off most leukemia cells but they don't kill off leukemic stem cells, so the disease eventually comes back."

Collaborating with U.S. scientists, Dick has recently been able to harness the immune system to selectively kill leukemic stem cells, but not normal ones. "One of the ways in which cancer develops is that a cell escapes recognition by the immune system," explains Dick. "What this therapy does is to teach the immune system to recognize and kill leukemic stem cells." The new therapy is expected to proceed to clinical trials in the near future, says Dick.

Dick's work also sets the stage for manipulation of normal stem cells to treat cancer and other diseases. For example, it may soon be possible to insert a protective gene into stem cells, enabling them to withstand heavier doses of chemotherapy used to treat solid tumours.

Dick is now trying to determine exactly how normal stem cells become abnormal by focussing on the actions of cancer-causing genes, also called oncogenes. He has been able to introduce these mutated genes into a normal stem cell and watch as the cell takes over abnormal blood cell production. "By gaining a better understanding of basic pathways, it is easier to devise therapies to interfere with that process," Dick says.

Standard treatments for leukemia are chemotherapy, sometimes combined with bone marrow transplantation — the transfusion of blood products to replenish stem cells damaged by cancer treatments. Although cure rates for childhood leukemia have improved greatly, the cure rate remains relatively low for some types of leukemia.

Leukemia rates are high in Canada, as in other industrialized countries. An estimated 3,500 Canadians will be diagnosed with leukemia this year and 2,100 people will die from the disease. Leukemia accounts for over 26 per cent of new cancer cases in children, and 32 per cent of deaths, making it the most common childhood cancer.

In addition to Dick, three top cancer researchers are receiving awards from the National Cancer Institute of Canada:

• Dr. George Browman is being presented with the O. Harold Warwick Prize, recognizing a body of critical research with a major impact on cancer control in Canada. His initial research brought knowledge from his own basic science work into the clinic using trials testing innovative treatment strategies. A groundbreaking study showed how smoking diminishes the effectiveness of radiation treatment in head and neck cancer. More recently, Browman has conducted research on transferring knowledge from clinical studies into routine patient care through evidence-based practice guidelines. Browman is Director of Cancer Care Ontario's internationally-recognized Program in Evidence-based Care which he founded, and which now involves cancer care professionals and community representatives in guideline development for cancer care. Browman is Professor, Departments of Clinical Epidemiology & Biostatistics, and Medicine at McMaster University, and Chief Executive Officer of the Hamilton Regional Cancer Centre.

• Dr. Timothy Whelan is being honoured with the William E. Rawls Prize, which recognizes investigators early in their career whose work has led to important advances in cancer control. Whelan has contributed significantly to cancer control through his role in clinical trials and health services research. In a recent study of women with breast cancer, Whelan found that three weeks of radiation treatment after a lumpectomy is just as effective as the standard five weeks. The study is good news for women who must undergo radiation, and has major implications for reducing waiting lists for this treatment. Whelan is now involved in a study to determine if additional radiation to surrounding lymph nodes will increase survival for women with early breast cancer. He has also been involved in other research studying the diverse needs of cancer patients, the coordination of supportive care services to meet those needs, and the development of a tool called the Decision Board to help doctors communicate with and involve patients in decisions about their care. Whelan is a radiation oncologist at the Hamilton Regional Cancer Centre and Associate Professor of Medicine, McMaster University.

• Dr. Chi-chung Hui is being awarded the Terry Fox Young Investigator Award, which honours a promising young investigator doing outstanding basic laboratory research. Hui has greatly increased our understanding of the biological process by which cancer develops. By identifying and studying specific genes involved in this process, Hui intends to develop ways to cure genetic defects that lead to cancer. Hui is a Scientist in the Program in Developmental Biology at The Hospital for Sick Children and Associate Professor, Faculty of Medicine, University of Toronto.

The Canadian Cancer Society (CCS) sponsors both the William E. Rawls Award and the O. Harold Warwick Award, while the Terry Fox Young Investigator Award is supported by The Terry Fox Foundation. The awards, administered by the National Cancer Institute of Canada (NCIC), are given annually to cancer researchers who are selected by eminent scientists across the country.

The NCIC's mission is to undertake and support cancer research and related programs in Canada that will lead to the reduction of the incidence, morbidity and mortality from cancer. The NCIC receives its funding from the CCS (75 per cent) and The Terry Fox Foundation (25 per cent).

Source: National Cancer Institute of Canada