Boffins are designing potent cancer treatments using their knowledge about an obesity drug, orlistat (Xenical or Alli) that was found to kill cancer cells in the laboratory.
The drug binds and interacts with a protein found in tumour cells and blocks the protein's function and causes cell death.
The study was conducted by a team of researchers including Steven Kridel and W. Todd Lowther at Wake Forest University School of Medicine.
As part of the study, scientists analysed prostate cancer cells to see which enzymes were expressed at high levels to develop treatments to inhibit those enzymes to stop tumour growth.
Researchers found that a protein known as fatty acid synthase was expressed at high levels in prostate tumour cells, and was fairly absent in normal cells.
Earlier researches have shown that the protein was found in many tumour cells including breast, colon, ovarian, liver, lung and brain.
"High levels of fatty acid synthase correlate with a poor prognosis so it is a great treatment target. This makes an exciting treatment target because theoretically you don't have to worry about harming nearby healthy tissue," Kridel said.
Scientists used X-ray crystallography to get a three-dimensional snapshot of the drug interacting with the protein.
"Understanding this drug-protein interaction is essential for designing new drugs," Lowther said.
Researchers then screened hundreds of thousands of compounds to identify the ones that interacted with cancer cells in the same way as orlistat and narrowed the list of possibilities down to a dozen.
The researchers will now work to create potent cancer treatments by testing the drugs in animals and then in human cancer patients.
The findings of the study were published in Nature Structural and Molecular Biology.