Evidence that Mifepristone, a progesterone receptor antagonist, can cross the blood brain barrier and provide palliative benefits for glioblastoma multiforme grade IV.

BACKGROUND: Mifepristone, a progesterone receptor antagonist, has been found to provide palliative benefits for various types of spontaneous murine cancer in randomized controlled trials and in anecdotal reports from a variety of advanced metastatic human cancer not known to be associated with progesterone receptors. The theory of its mechanism is that it prevents the secretion of a progesterone-induced immunomodulatory protein in the tumor microenvironment, or in the tumor cell itself, called the progesterone-induced blocking factor, which inhibits natural killer cells from attacking the cancer cell. Many anticancer chemotherapeutic agents fail to cross the blood-brain barrier and thus prove ineffective for brain cancer. The objective of the present study was to determine if mifepristone could provide palliative benefits to a patient with end-stage stage IV glioblastoma multiforme. CASE REPORT: A 43-year-old male with end-stage stage IV glioblastoma multiforme was exclusively treated with mifepristone 200 mg orally daily. RESULTS: The patient showed definite palliative effects for several weeks and his life was significantly extended beyond pre-treatment predictors. CONCLUSION: It appears that mifepristone does cross the blood-brain barrier and could be considered for palliative therapy of other patients with chemotherapy-resistant brain cancer.