Scientists at the British Columbia Cancer Agency in Vancouver, British Columbia, Canada, are the first in the world to decode a breast cancer DNA strand and to discover how and why breast cancer spreads and/or mutates to other areas in the body.

In a press release dated October 7, 2009, the British Columbia Cancer Agency stated that their scientists had successfully decoded all three billion letters in the DNA sequence of a metastatic lobular breast cancer that is responsible for 10% of all breast cancer diagnoses. The DNA mapping was conducted of a single breast cancer tumor of a patient as it metastasized.

They were able to use the latest DNA sequencing technology to compare the DNA strands from the "final cancer" with the DNA taken from the cancer when it was first diagnosed. What they discovered was certain mutations in various cells as the disease spread. To survive, cancer cells need certain proteins. When a cancer "realizes" its survival is threatened by treatment it will generate proteins that will instruct the cells to spread. Through state-of-the-art DNA sequencing technology they have identified what tells the cells what proteins to make and what proteins are necessary for the cell to survive and change.

All this was in a bid to answer the question of why some cancers, when they recur in a patient, seem to be resistant to treatment. One treatment that worked at the beginning may not work by the end. Scientists wanted to know why. Now scientists know.

Now that these mutations and proteins have been identified, treatment regimens can be tailored and adapted to target those mutation, prevent those mutations from occurring and keeping the cancer from spreading. If the cancer can't spread by eating healthy cells the tumor will die.

Not even five years ago, this type of sequencing would have taken months or years to complete. It is only recently that technology has advanced to the point where DNA sequencing of this nature could be completed in a few weeks.

The study about this finding and what it means for breast cancer treatments was published on October 8, 2009, in the international science journal, Nature.

To find out more, visit www.bccancer.bc.ca and go to "Newscentre."