Previous studies suggest that 70 per cent of breast cancers found in women are hormone dependent and can be treated with anti-hormone medicines such as tamoxifen.
Although tumour cells may initially respond to therapies, most eventually develop resistance which causes breast cancer cells to grow and spread.
Cholesterol also can contribute to the development of anti-hormone resistance because cholesterol is converted into hormones in tumour cells. Therefore, cholesterol-forming pathways are attractive therapeutic targets for the treatment of breast cancer.
Using a compound initially developed by Roche Pharmaceuticals for the treatment of high cholesterol, which reduces cholesterol in a different manner than the widely used statins, researchers at the University of Missouri administered the molecule to human breast cancer cells.
They found that the compound was effective in reducing human breast cancer cell growth and often caused cancer cell death.
They also found that the cholesterol lowering drug they tested destroyed an estrogen receptor, a protein which encourages the tumour cells to grow.
Researchers then tested the results in mice with breast cancer. Following injection of the compound, they found that the molecule was effective at killing breast cancer cells by reducing the presence of estrogen receptors in tumour cells.
"The compound exhibited anti-tumour properties in both human samples, which were outside the body, and in samples that were administered by injection into the mice," said Salman Hyder, the Zalk Endowed Professor in Tumour Angiogenesis and professor of biomedical sciences in the College of Veterinary Medicine and the Dalton Cardiovascular Research Center at MU.
"In both cases, the proteins that cause tumours to grow were eliminated, leading to more aggressive cell death," Hyder said.
Hyder believes that further clinical testing can lead to a drug that has the dual purpose of fighting high cholesterol and cancer.
The study was published in the journal Breast Cancer Research and Treatment.