Heparan Sulfate Proteoglycans Undergo Differential Expression Alterations in Alzheimer Disease Brains.

Previous studies have reported that heparan sulfate proteoglycans (HSPGs) promote amyloid-beta peptide and tau fibrillization in Alzheimer disease (AD) and provide resistance against proteolytic breakdown. We compared the expression levels of 17 HSPG core proteins in 18 AD cases and 6 controls. RT-PCR was used to analyze transcription levels. Immunohistochemistry was performed to localize HSPGs in the brain tissue. We detected expression of all HSPG genes investigated. SDC1, GPC3, and CD44v3 showed the lowest levels of expression, while SDC3 and GPC1 showed the highest. Remarkably, SDC4 and SRGN were overexpressed in most of the areas analyzed. Immunohistochemistry revealed the presence of both SDC4 and SRGN mostly associated with tau and amyloid-ß pathology throughout the AD brains. In conclusion, in view of the involvement of HSPGs in AD pathology, especially SDC4 and SRGN, there would seem to be a relationship between the regulation of core protein expression and the pathological features suggesting HSPGs are potential inducers of the disease.

Atypical bilateral cerebellopontine angle medulloblastoma: differential diagnosis, immunohistochemical features and radiological presentation.

Medulloblastoma (MB) is a highly aggressive soft tissue neoplasm, classified as a primitive neuroectodermal tumor. It is the most common posterior fossa tumor in children, but occurs rarely in adults. MB accounts for approximately 20% of all primary central nervous system (CNS) tumors of childhood, while its incidence is around 1% of adult brain tumors. Most often it occurs in the cerebellum. We report a case of multicentric MB involving the bilateral cerebellopontine angle (CPA) and right cerebellar hemisphere. The tumor showed isointensity on T1/T2-weighted images, and slight hyperintensity on T2-weighted fluid-attenuated inversion-recovery (FLAIR) images. The MB had restricted diffusion on diffusion-weighted images (DWI). It was not easy to make an accurate diagnosis before biopsy. The lesion in our patient presented with atypical MR image features of medulloblastoma. To our knowledge, this is the first case of bilateral CPA MB.

Multicentric spinal cord and brain glioblastoma without previous craniotomy.

BACKGROUND: Glioblastoma multiforme (GBS) is a highly malignant glioma that rarely presents as an infratentorial tumor. Multicentric gliomas lesions are widely separated in site and/or time and its incidence has been reported between 0.15 and 10%. Multicentric gliomas involving supratentorial and infratentorial region are even more rare. In most cases, infratentorial disease is seen after surgical manipulation or radiation therapy and is usually located in the cerebellum or cervical region. CASE REPORT: We present a rare case of symptomatic multicentric glioma in the brain, fourth ventricle, cervical as well as lumbar glioblastoma in an adult without previous therapeutic intervention. We also review the literature of this rare presentation. CONCLUSIONS: This report suggests that GBM is a diffuse disease; the more extended the disease, the worse prognosis it has. The management still remains controversial and further studies are required to understand the prognosis factors of dissemination.