New molecule
Faults in Wnt signalling are found in many cancers, particularly bowel cancer.  .

A new molecule that may prevent the development of certain cancers has been developed by Harvard Medical School scientists.

The new artificial molecule is called stapled peptide. It shuts down a cancer promoting molecule known as Wnt, which is part of a molecular signalling network that controls several normal cell processes. But this system of regulating the cell can go wrong and lead to cancer. Faults in Wnt signalling are found in many cancers, particularly bowel cancer, according to a Cancer Research UK report.

Scientists created the new molecule after studying another naturally occurring molecule called BCL9, which transmits signals sent by Wnt in cancer cells but not in healthy cells. The new artificial molecule stops signals being sent, thereby shutting off the cancer-driving signals, according to the findings published in the journal Science Translational Medicine.

The peptide molecule has so far only been tested in mice, but could also be used to cure cancer in humans, claim researchers.

The development is a result of a decades-long quest to find ways to block Wnt or the molecules it interacts with.

"One of the biggest challenges in cancer research is finding ways to disarm the molecules that fuel the disease, and blocking the interaction between proteins inside cells is notoriously difficult. This work builds on ours and [that of] other groups, and shows that it's possible to block the cancer-promoting interaction between BCL9 and beta-catenin, two key proteins in the Wnt signalling pathway," said Dr Mariann Bienz, a scientist from the MRC Laboratory of Molecular Biology in Cambridge, England.

"The technology they've used - called stapled peptides - is very interesting, and could be used against other molecules that are currently considered 'undruggable'."

Even though the study has found that the new molecule blocks the cancer promoting molecule, scientists still do not know whether stapled peptides-based treatments can effectively reach their targets inside cells, or how they are processed by the body.

"But this is a very active area of research, and it will be exciting to see where it leads," said Bienz.