Arsenic and Thalidomide may be used to fight cancer

Monday, April 11, 2005

A gathering of more than a thousand medical researchers in Sydney, Australia, has been told that arsenic and Thalidomide — banned in the 1960s after being linked to gross birth abnormalities — held hope as a basis for new treatments, extending the lives of patients with an so-far incurable bone marrow cancer, multiple myeloma.

Diagnosis of the disease has increased by 45% in Australia since 1992. It is the most lethal form of cancer, and the topic of discussion, at the 10th International Myeloma Workshop, continuing until the 16th of April.

The two treatments had advantages over existing chemotherapy treatments, including lessened side-effects, and reducing the need for chemo- and radiotherapy. They may also be usable to treat other illnesses. Both were still under test.

"The development of arsenic dates back many years when it was used for lowering the blood counts in patients, even at the turn of the century," Professor Miles Prince, of the Peter MacCallum Cancer Centre, told Australian Associated Press for the 10th International Myeloma Workshop.

"Subsequently [arsenic] was used in China since the 1960s for treating certain forms of Leukaemia," he said.

It could be used to induce the cell to "commit suicide".

"The side effects with Thalidomide are much less than with chemotherapy because it's not damaging innocent bystander cells - so you don't get low blood counts, you don't lose your hair, you don't get a sore mouth," he said.

"It was originally thought to work because [Thalidomide] blocks the blood vessel growth in tumours, and that is still true, but the research that we've done has shown that one of its major causes of action is to stimulate [ immune system ] T-cells which are directly against the tumour, and these T-cells help patients with myeloma fight their disease," Professor Douglas Joshua, head of Haemotology at Royal Prince Alfred Hospital in Sydney, told Australian radio.

"There's no doubt that with the new combinations of drugs - we've got Thalidomide, the sons of Thalidomide, Velcade and arsenic - we're adding years onto patient's lives and certainly it could add up to five years or more," according to Prof. Prince.