Reninoma is a rare form of kidney cancer with around 100 cases reported to date worldwide and is among the rarest of tumors in humans. Although it may be cured with surgery, it can lead to severe hypertension or spread and develop into metastases. In a new study, researchers at the Wellcome Sanger Institute, Great Ormond Street Hospital, and the Royal Free Hospital have cracked the genetic code of the rare form of kidney cancer.
The findings are published in Nature Communications in an article titled, “Targetable NOTCH1 rearrangements in reninoma,” and demonstrate a potential new drug target that could serve as an alternative treatment if surgery is not recommended.
Reninomas are exceedingly rare renin-secreting kidney tumors that derive from juxtaglomerular cells, specialized smooth muscle cells that reside at the vascular inlet of glomeruli,” wrote the researchers. “They are the central component of the juxtaglomerular apparatus which controls systemic blood pressure through the secretion of renin. We assess somatic changes in reninoma and find structural variants that generate canonical activating rearrangements of, NOTCH1 whilst removing its negative regulator, NRARP.”
The researchers found that there is a specific error in the genetic code of a known cancer gene, NOTCH1, that is behind the development of this rare cancer.
The team examined two cancer samples, one from a young adult and one from a child using whole genome and single nuclear sequencing. Their findings suggest that the use of existing drugs targeting this specific gene is a possible solution to treating reninoma for patients where surgery is not a viable option.
Taryn Treger, first author of the study and the Little Princess Trust Fellow at the Wellcome Sanger Institute, said: “Many cancerous tumors have already been deciphered with genomic technologies, however, this is not so true in rare cancers, particularly those affecting children. Our work aims to fill that gap. This is the first time that we have identified the drivers for reninoma and we hope that our work continues to pave the way towards new therapies for childhood cancers.”
“Rare kidney cancers known as reninomas do not respond to conventional anti-cancer therapies,” explained Tanzina Chowdhury, MD, co-lead author of the study, at Great Ormond Street Hospital. “The only known treatment at the moment is surgery. Our study shows that, actually, there is a specific and well-studied gene that drives this rare cancer. If we use already known drugs that affect this gene, we might be able to treat it without the need for an invasive technique such as surgery.”