BRCA Gene May Predict Drug Resistance in Ovarian Cancer, Study Finds
BRCA 1 and BRCA 2 are gene mutations long associated with a high risk for breast and ovarian cancer. Now, researchers at the University of Pennsylvania have found new evidence that it might also predict treatment resistance in ovarian cancers.
Breast cancer and ovarian cancer are both very serious and devastating diseases. The National Cancer Institute estimates that more than 250,000 people will be diagnosed with breast cancer this year, and over 40,000 will die from the disease.
Ovarian cancer is less common, with a projected 22,440 new cases. However, it carries a much higher mortality rate; there will be an expected 14,000 deaths or more this year from ovarian cancer. Most patients of this cancer are diagnosed late in the disease, making their recovery dependent upon getting the right treatment, fast. This is why drug resistant tumors pose a huge problem.
BRCA 1 and BRCA 2 are gene mutations which are associated with an increase in the risk of developing breast and ovarian cancer. But some researchers have also found evidence that could help with treatment resistance in patients suffering from ovarian cancer. Both breast cancer and ovarian cancer are dangerous medical conditions that have affected thousands of women around the world. The BRCA gene discovery is considered to be one of the major breakthroughs known to be related to a high risk in the history of breast cancer. Testing positive for the BRCA genes means that a person has a higher chance of developing either breast or ovarian cancer at some point in their life. If any family member inherits this gene, it would mean that they have one mutated and one normal copy. In one research study recently carried out, there were certain characteristics that were unique to cancer which expressed the BRCA mutation. The research group began to analyze the genetic profile of those patients to better understand a concept known as “double-hit hypothesis.” This concept has been a widely accepted theory in the field of cancer research. Individuals who have two of the normal BRCA alleles would require both copies of the BRCA to be mutated spontaneously before ever getting cancer. Those individuals who are BRCA negative would spend most of their lives free from cancer, and even if they did end up with breast or ovarian cancer, it is more likely they would get it in the later stage of their lives. The study compared survivors of ovarian cancer with and without the loss of hetereozygosity, and the researchers observed a significant number of difference in the life expectancies. Those individuals who had a second mutation were found to have a much lower response to the chemotherapies, which are platinum. To better understand what may have caused this phenomenon, it is important first to understand the workings of BRCA. It is essentially a gene that is known to code for a cell’s self-maintenance, thereby providing it the ability to repair its DNA. When an individual is carrying two BRCA mutated genes and fulfills the double-hit hypothesis, cancer cells are known to be lost presumably on both genes. So, for this group, there would be a need for platinum chemotherapies, which can effectively help the damaged DNA as well as possibly lead to the cancers dying since they are unable to repair their own genome.
Cancer patients who possess just one normal copy of the BRCA gene would still have some ability to repair their own DNA. The gene would provide those cancer cells a certain capacity to repair any damage caused by the platinum chemotherapy. So, this effectively explains why there is often a unique resistance in the case of ovarian tumors, which are known to carry just one of the normal BRCA alleles.