Antipsychotic drug shows cancer-fighting properties, researcher says

A drug used to treat schizophrenia could help treat cancer, says an Australian researcher.

Sarah Ongeley from the University of New South Wales reports preliminary research on an antipsychotic drug at this week's Australian Society for Medical Research conference in Sydney.

Epidemiological studies have found that schizophrenia patients have lower rates of cancer, especially lung cancer, than other people, even though they are more likely to smoke, says Ongeley.

Some scientists have proposed the medication they take could be protecting against cancer, by inhibiting cancer cell growth.

Ongeley tested a range of medications used to treat schizophrenia in the lab and came up with some interesting results.

She found the most promising was the antipsychotic called pimozide, which killed lung, breast and brain cancer cells in-vitro. The drug is approved for use as an antipsychotic in Canada.

Analysis of gene expression in the test cells showed their biosynthesis of lipids and cholesterol is boosted when pimozide is introduced, says Ongeley.

She is now trying to work out how pimozide kills cancer cells and to optimize its ability to do this.

"If we know how it works we can combine it with other drugs so the treatment will be more effective," says Ongeley.

Lower dose of drugs needed

Fast-dividing cancer cells need a certain amount of cholesterol and lipids to grow and this triggered Ongeley to test what happened when pimozide was combined with statin drugs, which stop cholesterol production.

"We found this increased cancer cell death. We needed a lower dose of drugs to kill the same amount of cells," she says.

Pimozide will soon be off-patent and Ongeley says she hopes clinical trials will be carried out in the not too distant future.

She says the plan would be to use high doses over short time periods, rather than the low doses over long periods used by people with schizophrenia.

The study of side-effects is yet to be carried out.

Ongeley is carrying out the research as part of her PhD, which is focusing on working out the cancer-fighting mechanism of pimozide, under the supervision of Dr. Louise Lutze-Mann.

The research was funded by the University of New South Wales.