Breast Cancer is the most common cancer in Canada. According to the Canadian Breast Cancer Foundation in 2009, an estimated 5,400 women and 50 men will die from breast cancer in Canada. It is also one of the most well researched cancers. In the last few years we have seen a number of breakthrough treatments for breast cancer such as Herceptin, a drug that targets the Her2 receptor. The Her2 receptor has been shown to be constitutively “on” in breast cancer, and is responsible for promoting cell growth, survival, adhesion and migration. Thus, by targeting the Her2 receptor, tumor growth and metastasis is severely hindered. However, not all breast cancers have the Her2 receptor overexpression phenotype and will therefore not be affected by the Her2 receptor phenotype. Although chemotherapy remains a leading treatment for cancer therapy, it is likely that a combination of drug treatments as well as chemotherapy offer the best chance of success. Interestingly, it is also well known that many cancers become resistant to drug therapies. These characteristics combined continue to plague scientists and hinder the development of effective cancer treatments. There is hope though. We can thank Canadian scientists from a B.C cancer agency for a novel breakthrough. Researchers here sequenced the genome (all 3 billion bases) from a patient’s original breast tumor, and a recurring tumor that arose in her pleural cavity nine years later. Surprisingly, they found that the genetic makeup of the two tumors were remarkable different. But they didn’t stop there. They then went on to look at the DNA from the tumors and found 32 different mutations among the 3 billion base pairs. This is a huge finding because scientists can now look into each one of these mutations, find what they encode (protein, mRNA, etc) and then see if they can develop drug therapies to target them. Most important is knowing the endogenous function of these genes and their importance in the normal functioning of a body cell. Hopefully, some proteins will show differential expression (or up/down regulation) between the normal body cell and the tumor cell. These can then be targeted for drug therapies. These seminal findings were published in Nature Journal earlier this week, and provide new hope into developing therapies and treatments to combat breast cancer.
– by Alisha Jamal, University of Toronto