What is a meningioma?
A meningioma is a tumor that develops from the meninges, the membranes that cover the brain and the spinal cord. Usually, they are benign (non-cancerous), however, when they become more aggressive, they can invade the brain and cause neurological deficits. Women are 2-3 times more likely to develop meningioma than men, but men tend to develop more aggressive forms of the disease. In children, radiation exposure increases the risk of developing a meningioma. Meningiomas can also be caused by rare genetic disorders such as neurofibromatosis type 2.
About 40 to 50% of individuals with meningiomas are asymptomatic. There are no standard tests for diagnosing an asymptomatic meningioma, hence it is often typically discovered when a patient undergoes routine magnetic resonance imaging (MRI) scan done for some other reason, or as a result of symptoms from a different condition. Surgery may be preferred to treat a meningioma that is located on the surface of the brain's convexity or if the symptoms include double vision, weakness in limbs, blindness, paralysis, or seizures. Patients with asymptomatic meningiomas are usually monitored by periodic MRI scans .
Recent breakthrough therapy for deadly meningioma tumors
When non-metastatic meningiomas recur after surgery and radiotherapy, patients have no options. In up to 20% of the cases, these aggressive tumors are untreatable and can even cause death. In collaboration with scientists from the University of California, San Francisco, and the University of Hong Kong, North-Western medicine scientists have now discovered a drug that prevents the growth of aggressive meningiomas as well as identifies which ones will respond to the drug. The newer drug for meningioma treatment is called “abemaciclib”. Abemaciclib inhibits tumor growth by blocking the cell cycle and acts as an epidermal growth factor receptor inhibitor. It is considered a breakthrough therapy for meningiomas .
Meningiomas and other malignancies frequently exhibit dysregulation of cell cycle regulators which suggests a potential therapeutic approach. CDK4/6 specific inhibitors like abemaciclib, are being intensively investigated in ongoing clinical trials as prospective treatment medications for meningioma patients in light of preclinical evidence that supports their usage. The effectiveness of the drug was examined in mice and a small number of patients. The drug prolonged the lives of the mice with meningiomas and slowed down the tumor growth. It has also been reported that Abemaciclib was used as an off-label drug in several patients whose tumors reduced in size and whose symptoms improved, pointing to the possibility of the drug being investigated in clinical trials , .
Efficiency of abemaciclib
Abemaciclib, a drug that inhibits the DNA polymerase enzyme, has shown promising results in clinical trials as a treatment for breast cancer and it has also been shown to be effective against prostate cancer. Abemaciclib has been approved for recurrent or progressive metastatic and/or locally advanced solid tumors. Diarrhea, nausea, and vomiting are the most common side effects. Besides slowing down tumor growth, this may also improve survival rates in some patients.
Abemaciclib is also being tested as a second-line treatment for patients with progressive cancers or after first-line chemotherapy. It can be used alone or in combination with surgery or radiotherapy. Preliminary study results are promising, though more research is needed before the medication can be adopted into clinical practice , .
Thus, abemaciclib can be an option for meningioma patients which can help them to have progression-free survival. The selection of patients for this drug and enhancing its efficacy and durability will require further research identifying response biomarkers and mechanisms of resistance.
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