Photo: Before the use of thioridazine (left) and after (right)
The team found that thioridazine, a treatment for mental illness, can kill cancer stem cells without producing toxic effects on healthy cells in the human body.
This gives hope for obtaining a broad-spectrum anticancer drug. By comparison, modern methods like standard chemotherapy work by “poisoning” all cells. As a result, patients experience hair loss, nausea, anemia, McMaster University staff say.
Stem cells are believed to be the basis of many types of cancers. In 1997, Canadian experts first found these cells in leukemia. To date, these cells have been found in cancers of the blood, breast, brain, lungs, gastrointestinal tract, prostate and ovaries.
Says Mik Bhatia, Director of the Institute for Stem Cell and Cancer Research: “Thioridazine kills cancer in an unusual way. It modifies stem cells, making them harmless. Normal cells are not affected. In the near future, it is planned to conduct clinical trials of the drug on persons with recurrent acute myeloid leukemia."
Thioridazine research also found that the drug works through a dopamine receptor located on the surface of cancer cells in leukemia and breast cancer. This means that in theory, the drug can be used as a marker to help diagnose cancer at the earliest stage.