Pamela Fayerman , Canwest News Service
Published: Thursday, July 03, 2008
VANCOUVER - To learn about what triggers breast cancer and how to create better treatments, scientists first have to know more about the composition and functioning of cells in normal breast tissue.
So, using discarded breast tissue, donated by patients and provided by four Vancouver plastic surgeons following breast reduction surgery, B.C. cancer researchers have been able to create a catalogue of genes present in healthy breast tissue.
In a study published Thursday in the journal Cell Stem Cell, 13 scientists from Vancouver, Britain and Ontario report on their highly technical analysis of normal human breast stem cells.
We know a lot about how to kill the bulk of the tumour, but what we don't know is how to shut down the factory that is producing the parts that make the cancer in the first place" said lead author Afshin Raouf, a researcher in the Terry Fox laboratory at the B.C. Cancer Agency.
His collaborators include other researchers at the cancer agency, the Ontario Cancer Institute, the University of B.C. and the United Kingdom Cambridge Research Institute.
Raouf said in an interview the research lays the groundwork for learning how to eliminate the stem cells that fuel breast cancer.
"We need to get smarter in drug design so that instead of killing every single molecule, we can spare healthy tissue with less toxic chemotherapy and be more specific about our biological targets. That's the ultimate goal," he said.
Researchers are focused on stem cells in breast tissue because they now realize that stem cells can be like "the bad seeds (that) produce cancer."
However, stem cells also play a good and necessary role in breast tissue: they help the mammary glands grow rapidly at puberty and they facilitate the expansion of breast cells during the menstrual cycle and especially during pregnancy when the breasts enlarge with cells to produce, store and secrete milk for breast-feeding infants.
"Stem cells are there to create the spare parts, but we now understand that when something goes wrong with the molecules in normal stem cells, it can lead to cancer.
So, before we can understand how genes get hijacked, we need to understand all the molecules present in healthy breast tissue, then compare them to those present in breast tumours," Raouf said.
"If you think of tumours as a sack of coloured marbles, and imagine that we are looking for the one red-coloured marble causing the cancer, you can understand that we are trying to isolate something specific so that we can create drugs that can find those specific targets."