A drug that is used to treat chronic myeloid leukaemia appears to be more effective at stopping a type of childhood brain cancer according to new research.
The drugs seemed to be more effective at treating the brain cancer, a medulloblastoma, in mouse models than existing treatments for the deadly paediatric brain tumour. The study was part of a multi-institutional team led by researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at University of California San Diego.
The hedgehog pathway
In the study, published in PLOS One, the team demonstrated how use of a single drug – in this case nilotinib – specifically targets cancer cells that have an abnormal activation of a cell communication system, called the Hedgehog pathway, via two different mechanisms, making it more effective and less toxic than combining drugs.
Senior author Ruben Abagyan, PhD, professor in the Skaggs School of Pharmacy, said: “We discovered a previously unknown activity of nilotinib that may be leveraged to treat a large fraction of cases of medulloblastoma, a type of childhood brain cancer.
“While more research is needed, this pharmaceutical could potentially be used for several cancer types with an overactive cell-signalling pathway.”
Several types of basal cell carcinoma, myeloid leukaemia, rhabdomyosarcoma, pancreatic adenocarcinoma, glioblastoma and one third of medulloblastoma cases have an impairment in the Hedgehog signalling pathway — a key cellular system that regulates embryonic development and adult tissue regeneration. As a result of this impairment, the cancer cells overproduce a cell-surface receptor called Smoothened.
Abagyan said: “Only a fraction of patients with this subtype of medulloblastoma respond well to current therapies that only target Smoothened.
“Knowing that dysregulation of the Hedgehog pathway is important to the maintenance of cancer stem cells, and that it plays a critical role in several cancers, we wanted to find a single drug that inhibits this pathway in addition to several other essential anti-cancer activities.”
Tumour growth reduced
In the study, the mice bearing human medulloblastoma tumours saw tumour growth reduced along with no drug resistance. Nilotinib simultaneously inhibits Smoothened and several protein kinases critical for tumour growth.
Nilotinib is already a US Food and Drug Administration approved therapy for chronic myeloid leukaemia with a safety profile, making it a good therapeutic candidate alone or in combination with surgery, radiation therapy and chemotherapy.