Two novel and orally administered drugs can not only block the growth but also reduce the size of a type of tumor found in the nervous system, new research has shown.
The tumors, known as schwannomas, most commonly grow on the nerves that carry auditory and balance information to the brain. Schwannomas are the most common nerve sheath tumor and can occur in anyone, but are also linked to an inherited condition known as neurofibromatosis type II (NF2).
With NF2, where the function of the protein merlin in cells is lost, patients often develop not only schwannomas but also meningioma tumors associated with the brain and spinal cord.
Both types of tumors are difficult to treat, with surgery currently being the mainstay, but also carrying a high risk of damage to surrounding normal nervous system tissue.
Faced with the urgent need for new treatments, an international team of scientists focused on the Hippo signaling pathway, which normally controls organ size in human tissues and cells but is dysregulated in several types of cancer.
Using a combination of patient-donor tumor cells from surgical resections and mouse models of schwannomas, the researchers showed that tumor growth can be greatly and significantly reduced after just 21 days of drug administration.
Furthermore, treatment with the Hippo pathway inhibitors (called VT1 and VT2 in the study) actually caused tumor cell death and an overall shrinkage in tumor size.
Drugs from this new class of hippo pathway inhibitors have also shown efficacy in another tumor type, mesothelioma, and are currently in phase 1 clinical trials.
Initial experiments with these new compounds show that they apparently also block the growth of meningioma tumor cells. Meningioma is not only a second tumor type that occurs in patients with NF2, but overall the most common tumor in the brain.
The effect of using these new therapies to treat both types of tumors simultaneously has the potential to be of great clinical value.
The study appears in the November issue of the journal Brainand was supported by Research Fellow Dr. Liyam Laraba and Professor of Neuroscience David Parkinson from the University of Plymouth.
It was supported by the Brain Tumor Research Charity, which funds a university center of excellence in low-grade brain cancer research, Vivace Therapeutics Inc and the Children’s Tumor Foundation.
dr Laraba, who completed the work as part of his Ph. These drugs are well tolerated in our models and we hope that our work can stimulate and accelerate the use of these inhibitors in clinical trials.”
Professor Parkinson, the study’s senior author, added: “Our current study provides an early indication that we may be able to offer schwannoma patients a successful alternative treatment to manage their condition. However, patients with neurofibromatosis type 2 often have both schwannoma and meningioma tumors affecting their nervous system. For these patients, the prospect of a single drug that could treat both types of tumors without the need for invasive and risky surgery is clearly an exciting prospect.”
Materials provided by University of Plymouth. Note: Content can be edited for style and length.