Research led by the Francis Crick Institute in London could help treat people with a rare skin condition called congenital melanocytic nevus syndrome using RNA silencing treatment.
Congenital melanocytic nevus syndrome is a mosaic genetic condition that results in around one percent of children being born with very large moles that can cover as much as 80% of their body surface. These moles can be painful or itchy and increase the risk for skin cancers such as melanoma in those affected.
In almost 70% of cases, congenital melanocytic nevi are caused by genetic variants in the NRAS gene, which encodes an enzyme known as the neuroblastoma RAS viral oncogene homolog and is linked to several types of cancer including neuroblastoma and melanoma.
Of those with an NRAS genetic mutation, the majority of patients have the same variant— NRAS c.181C>A, p.(Q61K).
In this study, published in the Journal of Investigative Dermatology, lead investigator Veronica Kinsler, group leader of the Mosaicism and Precision Medicine Laboratory at the Crick and a professor at UCL, and colleagues investigated potential treatments for this debilitating condition.
They created an RNA silencing therapy targeting the most common NRAS variant, which was packaged into lipid nanoparticles and successfully treated a mouse model of congenital melanocytic nevus syndrome with NRAS involvement. The team also tested the impact of RNA silencing on tissue samples donated by people with this condition.
The research team found that RNA silencing treatment caused the mole cells causing congenital melanocytic nevus syndrome to die.
“These results are very exciting, as not only does the genetic therapy trigger self-destruction of the mole cells in the lab, but we have managed to deliver it into the skin in mice,” said Kinsler in a press statement. “These results suggest that the treatment in future could potentially reverse moles in people, however more testing will be needed before we can give it to patients.”
If the treatment successfully moves through clinical trials, it could be an important treatment option for patients with congenital melanocytic nevi.
Jodi Whitehouse, CEO of Caring Matters Now, who helped to fund the research, said: “This breakthrough in finding a treatment for congenital melanocytic nevus syndrome could transform the lives of the families we support… As someone who was born with congenital melanocytic nevus covering 70% of my body and having undergone 30+ operations in my childhood to try and remove [it] because of the fear of melanoma, with no success, this news is awe-inspiring and exciting.”
