Genome Engineering

Breast cancer can be divided into two main types – oestrogen receptor-positive and oestrogen receptor-negative. Up to a third of breast cancers are oestrogen receptor-negative and are generally harder to treat because they are not responsive to treatments such as tamoxifen or other hormone-related treatments. There have been fewer advancements in therapeutics for this group. US researchers have linked a gene with this form of cancer and published the results in Nature.

The team of researchers, led by the Whitehead Institute for Biomedical Research, collaborating with Agios Pharmaceuticals, used RNA interference (RNAi)-based loss-of-function screening to analyse more than 133 potential metabolic targets in breast cancer cells. The negative-selection RNAi screening identified a set of metabolic genes associated with the cancer, including the gene expressing phosphoglycerate dehydrogenase (PHGDH).

Around 70% of the oestrogen-receptor-negative breast cancers had raised levels of the PHGDH protein. The researchers found that suppressing the PHGDH gene slowed the cancer growth in the lab. These findings could lead to potential treatments for this form of cancer.

Whereas this gene is linked with the tumour’s response to treatment, some gene mutations increase the risk of developing cancer. Tests are available for the BRCA gene mutation that increases the risk of getting breast cancer to up to 80% for the carrier, but the decision to be tested is not easy, and some people have even opted for pre-implantation diagnosis to have a baby free of the genes.