Silencing of gene helps to fight breast cancer
Silencing a gene that interact with the breast cancer gene BRCA1, makes the breast cancer cells more sensitive to radiation therapy as per findings from research presented at American Association of Cancer Research (AACR). As per the new research findings by Xiaowei Chen, PHD from Fox Chase Cancer Center, silencing of a gene that has direct interaction with BRCA1 gene would make breast cancer cells more susceptible to radiation. By silencing this gene the number of breast cancer cells that are killed with radiation (rate of apoptosis in the breast cancer cell line after radiation) are increased by about 10%.
Previous research has shown that the gene BRCC36 interacts directly with the breast cancer associated gene1 otherwise known as BRCA1. BRCC36 is over-expressed in majority of breast cancers. BRCA1 is a DNA repair gene, and by silencing the BRCC36 gene, less repair of DNA would occur and this can lead to increase killing of breast cancer cells during radiation therapy.
The researchers used breast cancer cell lines to test this theory and used molecular techniques to reduce the expression of BRCC36 gene. This resulted in 80 percent reduction of expression of the BRCC36 gene. These breast cancer cells were then subjected to ionizing radiation together with a control in which the expression of BRCC36 was not controlled.
Breast cancer cells which had silencing of BRCC36 had greater cell death rates (apoptosis) with ionizing radiation compared to cells in which BRCC36 was not silenced (46% Vs 35%).
These findings are very significant and new drugs can be designed to silence BRCC36 and may be it can be used in combination with radiation therapy to achieve better control of breast cancer after surgery. This approach may be especially useful in patients who have tumors that are resistant to radiation therapy. Understanding how silencing of BRCC36 increases sensitivity of breast cancer cells to radiation, we may be able to develop new drugs to better fight breast cancer.