Researcher Now researchers from the University of East Anglia and the Children’s Hospital Boston, US, have had success treating the cancer with leflunomide, a drug originally designed to treat rheumatoid arthritis.
"Melanomas are a cancer of the melanocytes which are the pigment cells in our skin," says Dr Grant Wheeler, lead author of the study. "They are much more dangerous and more aggressive because they are far more likely to become malignant or invasive and cause secondary tumours elsewhere in the body. This is why it is so important to catch them early."
Using tadpoles, they checked thousands of different chemical compounds to see if they could slow the growth of pigment cells. And although you might think studying tadpoles wouldn’t shed much light on human cancers, this particular species of frog has proved useful. "The frog species (we used) has the same organs, molecules and physiology as humans," says Wheeler. "This means that the same mechanisms are potentially involved in causing cancer in both."
Of the thousands of compounds checked, several did slow development in the tadpoles' pigment cells. When they tested the compounds on mice, they found that leflunomide significantly slowed tumour growth. When they combined leflunomide with another medication – PLX4720 – which is also being tested to treat skin cancer, the results were very promising. Tumour growth was almost completely stopped.
Clinical trials to check the effects of the treatment on patients will soon begin, which will allow the researchers to assess exactly how effective it is for human skin cancer.
First published March 24, 2011