From epidemiology and neurodevelopment to antineoplasticity. Medroxyprogesterone reduces human glial tumor growth in vitro and C6 glioma in rat brain in vivo

OBJECTIVE

Glial tumor growth may accelerate during gestation, but epidemiological studies consistently demonstrated that parousity reduces life long risk of glial tumors. Pregnancy may also accelerate growth of medulloblastoma and meningioma, but parousity does not confer protection against these tumors. We were the first to show that medroxyprogesterone acetate (MPA) reduces rat C6 glioma growth in vitro. Now we aimed to determine the effects of MPA on human brain cancers (particularly glioblastoma) in vitro and C6 glioma in vivo.

PATIENTS AND METHODS

We evaluated the effects of MPA on: i) monolayer growth of human U87 and U251 glioblastoma, ii) 3D-spheroid growth and invasion of C6 rat glioma and human U251 glioma, iii) interactions with PI3-Kinase inhibitors and coxsackie-adenovirus receptor (CAR) in modifying 3D-spheroid invasion of glioma.

RESULTS

MPA at low doses (3.25-13 μM) insignificantly stimulated and at high doses (above 52 μM) strongly suppressed the growth of human U87 and U251 cells in vitro. MPA also binds to glucocorticoid receptors similar to dexamethasone (Dex) and unexpectedly, PI3-Kinase inhibitors at low doses suppressed anti-invasive efficacies of MPA and Dex. MPA exerted higher invasion-inhibitory effects on CAR-expressing human glioma cells. Lastly, MPA suppressed growth of C6 glioma implanted into rat brain.

CONCLUSION

Progesterone analogues deserve to be studied in future experimental models of high grade glial brain tumors.

Idiopathic Tolosa-Hunt syndrome: four additional cases

Idiopathic Tolosa-Hunt syndrome (ITHS) is a very rare cause of painful ophthalmoplegia characterized by unilateral orbital pain, ipsilateral oculomotor paralysis and prompt response to steroids. In this paper we report 4 additional cases of ITHS. This rare cause of painful ophthalmoplegia effects the cranial nerves due to a granulomatous lesion of unknown etiology in the cavernous sinus or superior orbital fissure. The International Headache Society redefined the diagnostic criteria for ITHS but it is still mostly a diagnosis of exclusion. Careful evaluation and follow-up is essential for diagnosis. Optimal therapy duration and dosage and prophylactic treatment in recurrent cases needs further research.

Methodological considerations for the development of new treatments for bipolar disorder

Lithium has been the drug of choice in treating bipolar disorder for 50 years and, therefore, patterns of response associated with its use define what we expect from treatment. Although efforts to establish some other agents as antimanic have been successful, it is difficult to assess their overall efficacy in relation to that of lithium without a better understanding of inclusion/exclusion criteria, subtypes, definitions of remission, relapse and recurrence, and duration of study. All of these factors need to be carefully addressed to identify the most important clinical targets for new drug development. Additional relevant information emerges from studies on combinations of mood stabilisers, efficacy of antimanic agents in different patient populations, analysis of rates of drop-out, non-compliance, suicide, drug abuse, and discontinuation especially with long-term treatment. Agents other than lithium that are effective in the acute phase treatment are still not well characterised as mood stabilisers. New agents need to be evaluated in the context of long-term treatment and the targeting of specific components of the syndrome beyond mania.

HLA antigens in schizophrenia and mood disorders

The frequencies of HLA antigens were examined in a sample of 75 patients with schizophrenia and 35 patients with mood disorders. We compared the data obtained from this population with data obtained in another study with 3731 healthy subjects. Statistically significant increases were observed in the frequencies of HLA A10, A11, and A29 and a statistically significant decrease was observed in the frequency of HLA A2 in patients with schizophrenia. The increased frequency in HLA B16 in patients with mood disorders was also statistically significant.