London: Researchers have found that certain existing drugs could be used to effectively treat, or even prevent, hereditary stomach and breast cancers.

There is currently no treatment for this kind of gastric cancer other than surgical removal of the stomach as a preventive measure in those identified as carrying the mutated gene. Lobular breast cancer is hard to detect by mammography and mastectomies are also undertaken by some carriers.

But the new findings, published in the journal Molecular Cancer Therapeutics, suggest that people at genetic risk of these diseases may soon be spared of taking such hard decisions.

“Making such drug treatments a reality would mean delaying or completely avoiding the trauma that high-risk individuals experience by undergoing major preventive surgery at a young age,” said lead researcher Parry Guilford, professor at the University of Otago in New Zealand.

The researchers found that key genetic mutation underlying the devastating conditions also opens them to attack through drug therapies targeting other cellular mechanisms.

The team used genomic screening to search for vulnerabilities in the cancer cells that lack the tumour-suppressor protein E-cadherin.

The genetic mutation that causes this protein to be lost is common in hereditary diffuse gastric and lobular breast cancers.

E-cadherin is not a traditional drug target for these forms of cancer because the protein is present in healthy cells but absent in malignant ones.

However, professor Guilford and his team predicted that its loss might create other vulnerabilities in these cancer cells and they were proved right.

Next, the researchers screened selected drug classes known to interfere with these proteins, and found that early chemoprevention treatments could be developed for people who carry the E-cadherin mutation and as a result are at high risk of gastric and lobular breast cancers.