Stopping cancer spreading
Working with 'substitute' breast cancer stem cells and mice, scientists have discovered a chemical which can kill the cells that cause tumours to spread and return, even after seemingly successful treatment. The research, which involves a completely new way of identifying cancer medicines, could pave the way for a treatment that could kill cancer stem cells without harming other cells in the body.
Evidence is growing rapidly that cancer stem cells are responsible for the aggressive powers of many tumours. Because the cancer stem cells are so rare, are relatively resistant to treatment, and are difficult to grow in the laboratory, the team worked on substitutes created from normal cells which were altered to adopt some of the properties of cancer stem cells. They then bombarded these substitute cells with chemicals to see if any had an effect.
Screening 16,000 compounds, researchers found 32 promising candidates. Of these one stood out. Salinomycin, an antibacterial and anti parasite compound normally used for chickens and pigs, killed 100 times more cancer stem cells than standard chemotherapy. It killed not only the substitute cancer stem cells, but also real ones, and reduced breast tumour growth in mice. The mouse studies showed that it seemed to suppress the genes that are linked to particularly aggressive tumours and that lower chances of survival.
Further research will establish if the chemical has the same effect in humans.