Australasian Science: Australia's authority on science since 1938

Mistletoe Kisses Off Cancer

By Stephen Luntz

Mistletoe extract is a potent killer of colon cancer cell lines, but some species work better than others according to an Adelaide University study.

Mistletoe has been renowned for its medical uses since pre-Roman times, and enough clinical studies have been conducted for it to be authorised for use against colon and breast cancer in Europe, although not Australia.

Honours student Zahra Lotfollahi compared three species of the semi-parasitic plant that grow on oak, ash and apple trees against a common chemotherapy drug. The Fraxini mistletoe, which lives on ash trees, was able to kill cancer cell lines at lower concentrations than the chemotherapy chemical. It also did less harm to healthy colon cells.

“This is an important result because we know that chemotherapy is effective at killing healthy cells as well as cancer cells. This can result in severe side-effects for the patient, such as oral mucositis (ulcers in the mouth) and hair loss,” says Lotfollahi.

The other mistletoe species were not only less potent against cancer but were also as likely to damage healthy as diseased cells. Lotfollahi’s supervisor, Prof Gordon Howarth, noted that other species of mistletoe had not been tested, and cautioned against jumping to conclusions.

Lotfollahi hopes to study mistletoe lectins, which are believed to be the active chemical, as part of her PhD. She says it is not known what benefit the mistletoe gets from the lectins, and why the concentration is higher in Fraxini than on the species that inhabit other trees.