The endoscopic endonasal transsphenoidal approach has been proposed in the past decade as a minimally invasive surgical technique for the removal of pituitary tumors. From January 1997 to November 1999, 100 consecutive patients with pituitary tumors underwent endoscopic endonasal surgery, according to Jho's technique. We employed 0°, 30°, 45°, and 70° rigid endoscopes, 18 - 30 cm in length, 4 mm in diameter with an outer sleeve for irrigation and secured to a holder. Among the 87 pituitary adenomas, tumor removal was total in 51, subtotal (> 80 %) in 20 and partial in 16 cases. Four craniopharyngiomas were totally removed and an intra-suprasellar arachnoid cyst was emptied; a biopsy was performed in the two patients with a clivus chordoma. The two cases of sphenoid sinusitis were cured by surgery, the three patients with spontaneous CSF rhinorrhea were successfully treated and the residual nasal meningocele was removed. The endoscopic endonasal transsphenoidal approach appeared to be less traumatic than the traditional microsurgical approach, was very effective, and was characterized by a reduced number of complications. However, the relatively small series together with the short follow-up do not allow us to draw definitive conclusions. The post-operative reduction in hospital stay (two days in 40 of 100), significantly reduced the cost of patient's management.

The role of dopamine agonist treatment in corticotroph pituitary tumors is controversial. The aim of this study was to evaluate D₂ receptor expression in 20 corticotroph pituitary tumors and to correlate it to the in vitro effect of dopamine agonists on ACTH secretion and the in vivo effect of short-term cabergoline treatment on cortisol secretion. D₂ expression was evaluated by receptor-ligand binding, immunohistochemistry, and RT-PCR. A 50% or more decrease in daily urinary cortisol levels was considered a significant clinical response. At receptor-ligand binding, specific binding of [¹²⁵I]epidepride was found in 80% of cases. At immunohistochemistry, specific D₂ immunostaining was found in 75% of cases. D₂ expression was found in 83.3% of cases (D_2long in 40%, D_2short in 20%, and both in 40%) by RT-PCR. Significant in vitro inhibition of ACTH secretion was found in 100% of D₂-positive cases, but not in 100% of D₂-negative cases by either bromocriptine or cabergoline. A significant in vivo inhibition of cortisol secretion after 3-month cabergoline treatment was found in 60%, although a normalization of cortisol secretion was found in 40% of cases. All cabergoline-responsive cases were associated with D₂ expression, whereas all noncabergoline-responsive cases but one were not associated with D₂ expression. In conclusion, functional D₂ receptors were expressed in approximately 80% of corticotroph pituitary tumors. The effectiveness of cabergoline in normalizing cortisol secretion in 40% of cases supports its therapeutic use in the management of Cushing’s disease.

Glioblastoma is the most frequent brain tumor in adults and is the most lethal form of human cancer. Despite the improvements in treatments, survival of patients remains poor. In order to identify microRNAs (miRs) involved in glioma tumorigenesis, we evaluated, by a miRarray, differential expression of miRs in the tumorigenic glioma LN-18, LN-229 and U87MG cells compared with the non-tumorigenic T98G cells. Among different miRs we focused our attention on miR-221 and -222. We demonstrated the presence of a binding site for these two miRs in the 3′ untranslated region of the protein tyrosine phosphatase μ (PTPμ). Previous studies indicated that PTPμ suppresses cell migration and is downregulated in glioblastoma. Significantly, we found that miR-221 and -222 overexpression induced a downregulation of PTPμ as analyzed by both western blot and real-time PCR. Furthermore, miR-222 and -221 induced an increase in cell migration and growth in soft agar in glioma cells. Interestingly, the re-expression of PTPμ gene was able to revert the miR-222 and -221 effects on cell migration. Furthermore, we found an inverse correlation between miR-221 and -222 and PTPμ in human glioma cancer samples. In conclusion, our results suggest that miR-221 and -222 regulate glioma tumorigenesis at least in part through the control of PTPμ protein expression.

The role of macrophages in the growth and the progression of tumors has been extensively studied in recent years. A large body of data demonstrates that macrophage polarization plays an essential role in the growth and progression of brain tumors, such as gliomas, meningiomas, and medulloblastomas. The brain neoplasm cells have the ability to influence the polarization state of the tumor associated macrophages. In turn, innate immunity cells have a decisive role through regulation of the acquired immune response, but also through humoral cross-talking with cancer cells in the tumor microenvironment. Neoangiogenesis, which is an essential element in glial tumor progression, is even regulated by the tumor associated macrophages, whose activity is linked to other factors, such as hypoxia. In addition, macrophages play a decisive role in establishing the entry into the bloodstream of cancer cells. As is well known, the latter phenomenon is also present in brain tumors, even if they only rarely metastasize. Looking ahead in the future, we can imagine that characterizing the relationships between tumor and tumor associated macrophage, as well as the study of circulating tumor cells, could give us useful tools in prognostic evaluation and therapy. More generally, the study of innate immunity in brain tumors can boost the development of new forms of immunotherapy.

Epigenetic changes in DNA methylation contribute to the development of many diseases, including cancer. In glioblastoma multiforme, the most prevalent primary brain cancer and an incurable tumor with a median survival time of 15 months, a single epigenetic modification, the methylation of the O⁶-Methylguanine-DNA Methyltransferase (MGMT) gene, is a valid biomarker for predicting response to therapy with alkylating agents and also, independently, prognosis. More recently, the progress from single gene to whole-genome analysis of DNA methylation has allowed a better subclassification of glioblastomas. Here, we review the clinically relevant information that can be obtained by studying MGMT gene and whole-genome DNA methylation changes in glioblastomas, also highlighting benefits, including those of liquid biopsy, and pitfalls of the different detection methods. Finally, we discuss how changes in DNA methylation, especially in glioblastomas bearing mutations in the Isocitrate Dehydrogenase (IDH) 1 and 2 genes, can be exploited as targets for tailoring therapy.