Molecule behind Huntington's disease found to be cancer-killing super assassin

For several years, scientists have noticed an unexplained reduced incidence of cancer in patients suffering from the devastating hereditary neurodegenerative condition Huntington's disease. Now a team at Northwestern Medicine has uncovered how the disease could be inadvertently killing cancer cells, and how this process could be harnessed for a new cancer treatment. 

Huntington's disease is caused by a mutation in a gene called huntingtin. The mutation generates repeating RNA sequences and these repeating sequences, known as small interfering RNAs (siRNAs) are what slowly damage neural cells, causing the progressive neurodegeneration associated with the condition.

Previous research by the same Northwestern team discovered that siRNA molecules were amazing cancer-killing assassins that evolved in living organisms millions of years ago to fight cancer before the more complex adaptive immune system developed. This research inspired the team to investigate whether there were diseases involving similar RNA mechanisms that also correspond with lower rates of cancer.

The repeating siRNA sequences found in Huntington's pathology were discovered to be very similar to the siRNA molecules identified in the team's earlier work. So the next step was to test whether this particular molecule, when delivered via nanoparticles to mice, actually worked to kill cancer cells. The results were remarkable. Tumor growth was significantly reduced in a huge variety of different cancer cell lines, including ovarian, breast, prostate, liver, brain, lung, skin and colon cancer cells.