Treatment to cure breast cancer for good gets closer

Washington D.C: A team of researchers has found the 'Achilles heel' of breast cancer, paving the way for a treatment that would cure it for good.

Scientists from the University of Zurich discovered why current treatments do not kill off the disease but render it dormant, meaning it can become active again at any time. They also found a way to 'switch off' the signals that tell cancer cells to grow and divide.

Many invasive forms of breast cancer have too much of the receptor HER2 (human epidermal growth factor receptor 2) on their surface, which leads to uncontrolled growth of the cancer cells.

HER2 uses several signalling pathways at the same time to inform the cell that it should grow and divide. But, currently, the antibodies available only block one of those signalling pathways, while others remain active.

Now, scientists believe they have developed a method to switch off all the signals, using a protein compound that binds to HER2 and changes its structure.

This 'receptor bending' prevents any growth signals from being transmitted to the cell's interior, causing the cancer cell to eventually die.

This new technique is especially promising, as tests on mice found only the cancer cells were targeted, leaving healthy cells unharmed.

The active ingredient, which comprises several DARPins (designed ankyrin repeat proteins), is also easy to produce. A similar substance is currently being developed for testing in the future.

Lead author Dr Andreas Plückthun said the discovery of the Achilles heel of HER2-positive cancer cells could lead to new opportunities for treating invasive tumour types like breast cancer more effectively in the future.

The study appears in Nature Communications.