Nose Drops: A New Brain Cancer Treatment
Treating brain cancer with a drug dispensed through nose drops may be in our future. Results of a new study, published in the American Chemical Society’s journal Molecular Pharmaceutics, provide evidence of a potential new way to treat brain tumors as well as other central nervous system disorders.
Brain Cancer is Deadly and Difficult to Treat
One of the biggest challenges facing doctors and patients who have brain cancer is that currently available anticancer drugs have trouble reaching the brain because the protective layer that surrounds the brain (blood-brain barrier) prevents medications in the blood from entering the brain. A team of Japanese scientists have found a way to avoid this barrier to treating brain cancer by delivering chemotherapy through the nose.
The direct physical connection between the nasal cavity and the central nervous system makes it possible to deliver medications and other substances through the nose. It is the only location in the human body where the nervous system directly contacts the surrounding environment. Thus this is a unique opportunity to reach the brain through the nose.
Tomotaka Shingaki and colleagues tested delivery of the anticancer drug methotrexate as nose drops on laboratory rats that had brain cancer and had a control group that received an injectable form of the drug. Compared with the latter group, the brain tumors in the rats that received the nose drops reduced in weight by about one-third.
Along with the methotrexate, a diuretic called acetazolamide was mixed with the nose drops in the study. Acetazolamide enhances the efficacy of nasal methotrexate, and experts believe it may reduce systemic side effects associated with the anticancer drug. Serious side effects associated with methotrexate include liver and lung damage, severe skin infections, and lowered immunity.
The National Cancer Institute estimates that 22,020 new cases of brain and other nervous system cancers will be diagnosed in the United States in 2010, and that 13,140 people will lose their lives to the disease.
This study is an important step toward a new, effective way to treat brain cancer. Delivery of medications via nose drops or nasal spray may be applicable not only for brain tumors but for other disorders of the central nervous system as well.
National Cancer Institute
Shingaki T et al. Molecular Pharmaceutics 2010 July