Hope for Treatment of Gene Variant Linked to Breast Cancer Spread – Study

Korede Abdullah in Lagos

Researchers have made a landmark discovery that a gene variant involved in setting cholesterol levels may also determine whether breast cancer spreads to other parts of the body.

A study published in Cell on December 9 found that a variant of the PCSK9 gene drives the spread of breast cancer. However, a lab-made antibody already approved to treat high cholesterol may help stop the spread of cancer cells.

According to oncologist and cancer biologist Sohail Tavazoie of the Rockefeller University in New York City, researchers have been searching for mutations that spur the migration of breast cancer cells for years.

However, it was cancer biologist Wenbin Mei who wondered if inherited genetic variants might give cancer cells the ability to spread. Mei and colleagues found that a variant of the PCSK9 gene was associated with the metastasis, or spread, of breast cancer.

The study found that people who inherited two copies of the spread-associated variant have a significantly higher risk of developing metastasis within 15 years of their original diagnosis.

Approximately 70% of people of European or African descent have two copies of the variant, while nearly all Asians, especially East Asians, have two copies. The researchers also discovered that the variant removes a protein that acts as a brake on two genes that spur cancer spread.

A protein made by the pathogenic version of PCSK9 can be prevented from removing the brake by an antibody already approved as a treatment for high cholesterol.

According to Tavazoie, “we see that we get a reduction in breast cancer metastasis… It’s not a cure, it’s a reduction.” Clinical trials may determine whether the antibody could help prevent cancer spread or improve survival in patients who already have metastatic breast cancer.