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.