Single-cell analysis of human glioma and immune cells identifies S100A4 as an immunotherapy target.

A major rate-limiting step in developing more effective immunotherapies for GBM is our inadequate understanding of the cellular complexity and the molecular heterogeneity of immune infiltrates in gliomas. Here, we report an integrated analysis of 201,986 human glioma, immune, and other stromal cells at the single cell level. In doing so, we discover extensive spatial and molecular heterogeneity in immune infiltrates. We identify molecular signatures for nine distinct myeloid cell subtypes, of which five are independent prognostic indicators of glioma patient survival. Furthermore, we identify S100A4 as a regulator of immune suppressive T and myeloid cells in GBM and demonstrate that deleting S100a4 in non-cancer cells is sufficient to reprogram the immune landscape and significantly improve survival. This study provides insights into spatial, molecular, and functional heterogeneity of glioma and glioma-associated immune cells and demonstrates the utility of this dataset for discovering therapeutic targets for this poorly immunogenic cancer.

Metastatic urothelial carcinoma to the brain, spinal cord and spine: A contemporary multi-institutional clinicopathologic analysis of 24 cases.

Only case reports and small series of metastatic urothelial carcinoma (UCa) to the central nervous system (CNS) or spine have been published. We identified 24 cases at our institutions. The mean patient age was 64 years (range: 41-78 years) with a male predominance. Nineteen (79%) cases involved the brain, 3 (13%) and 2 (8%) cases involved the spinal cord and spine, respectively. Most cases (79%) were a single mass with a mean size of 2.8 cm (range: 0.9-5.5 cm). With the exception of 3 cases demonstrating micropapillary UCa, all metastases showed morphologic features of conventional UCa. Prior to CNS and spinal metastases, there was a history of UCa involving only the bladder in 16 (67%) patients, ureter in 1 (4%) patient, and kidney/renal pelvis in 1 (4%) patient. In 1 additional patient (4%) each, the primary tumor involved both bladder and ureter, bladder and kidney/renal pelvis, and ureter and kidney/renal pelvis, respectively. Three (13%) patients had no known primary site. In two patients, the diagnosis of primary UCa was made concurrently as the CNS metastasis, and ranged up to 30 years in other patients. Follow-up was available in 14 patients with a mean duration of 7 months (range: 0-23 months), and 4 patients died of disease. Both clinicians and pathologists should be aware that concurrent or late CNS or spine metastases may occur and could present as a solitary mass even over a decade after the initial diagnosis.

ATRX protein loss and deregulation of PI3K/AKT pathway is frequent in pilocytic astrocytoma with anaplastic features.

INTRODUCTION: Pilocytic astrocytoma (PA) with anaplastic features (PAAF) is a rare entity associated with decreased survival. It is characterized by hypercellularity, atypia, brisk mitotic activity, variable necrosis, and association with a classic PA component or anaplastic transformation in a recurrent tumor with a previously-documented classic PA. MATERIALS AND METHODS: We present 5 PAAF cases with clinical, radiological, pathological, and molecular correlation. We interrogated ATRX, IDH, TP53, PTEN, EGFR, BRAF, 6q23, p16(Ink4a) by sequencing, FISH, and immunohistochemistry. RESULTS: Four tumors were located in the cerebellum, and 1 was supratentorial. All showed ATRX protein loss by immunohistochemistry, loss of heterozygosity for PTEN, and had no IDH/TP53/BRAF mutations, nor EGFR amplification. Two of 5 tumors showed BRAF duplication by pyrosequencing. All showed loss of PTEN nuclear expression in subsets of tumor cells, which was associated with variable cytoplasmic positivity for pS6. There was a relative correlation between loss of PTEN expression and pS6 cytoplasmic expression. p53 was expressed in ~ 50% of tumor cells in all tumors. P16 was variably lost in all cases. One tumor showed MYB/6q23 deletion. CONCLUSION: We confirm ATRX protein loss suggestive of ATRX alteration as well as dysregulation of the PI3K/AKT pathway and, less often, of the MAPK/ERK pathway in PAAF.
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Phosphorylated TDP-43 (pTDP-43) aggregates in the axial skeletal muscle of patients with sporadic and familial amyotrophic lateral sclerosis.

Muscle atrophy with weakness is a core feature of amyotrophic lateral sclerosis (ALS) that has long been attributed to motor neuron loss alone. However, several studies in ALS patients, and more so in animal models, have challenged this assumption with the latter providing direct evidence that muscle can play an active role in the disease. Here, we examined the possible role of cell autonomous pathology in 148 skeletal muscle samples from 57 ALS patients, identifying phosphorylated TAR DNA-binding protein (pTDP-43) inclusions in the muscle fibers of 19 patients (33.3%) and 24 tissue samples (16.2% of specimens). A muscle group-specific difference was identified with pTDP-43 pathology being significantly more common in axial (paraspinous, diaphragm) than appendicular muscles (P = 0.0087). This pathology was not significantly associated with pertinent clinical, genetic (c9ALS) or nervous system pathologic data, suggesting it is not limited to any particular subgroup of ALS patients. Among 25 non-ALS muscle samples, pTDP-43 inclusions were seen only in the autophagy-related disorder inclusion body myositis (IBM) (n = 4), where they were more diffuse than in positive ALS samples (P = 0.007). As in IBM samples, pTDP-43 aggregates in ALS were p62/ sequestosome-1-positive, potentially indicating induction of autophagy. Phospho-TDP-43-positive ALS and IBM samples also showed significant up-regulation of TARDBP and SQSTM1 expression. These findings implicate axial skeletal muscle as an additional site of pTDP-43 pathology in some ALS patients, including sporadic and familial cases, which is deserving of further investigation.

Creutzfeldt astrocytes may be seen in IDH-wildtype glioblastoma and retain expression of DNA repair and chromatin binding proteins.

Astrocytes with multiple micronuclei ("Creutzfeldt cells") in a brain biopsy are classically associated with demyelinating disease. However, glioblastoma may also have prominent Creutzfeldt astrocytes, along with granular mitoses. Therefore, Creutzfeldt cells may raise the diagnostic dilemma of high-grade glioma vs tumefactive demyelination. While cases of glioblastoma (GBM) with Creutzfeldt astrocytes have been reported, their clinicopathologic spectrum and genetic features are not understood. Studies have proposed that micronuclei in Creutzfeldt cells are a consequence of DNA damage, or may be susceptible to DNA damage and chromothripsis, but their biology in the context of glioblastoma remains unclear. Based on a challenging index case of GBM with mild hypercellularity, Creutzfeldt astrocytes, and granular mitoses on biopsy, we searched our archives for additional cases with similar histopathologic features. We identified 13 cases, reviewed their clinico-radiologic and pathologic features, and examined them for recurrent genetic alterations via NGS (9 cases) and for evidence of DNA damage by immunohistochemistry for DNA repair and chromatin remodeling proteins. We found that Creutzfeldt cell-rich GBMs were IDH-wildtype with no recurring genetic alterations. To test our hypothesis that micronuclei demonstrate loss of DNA repair or chromatin remodeling proteins, we examined the expression of various proteins (MDM2, p53, MLH1, MSH2, PMS2, MSH6, ATRX, INI1, SATB2, Ki67, pHH3) in Creutzfeldt cell rich-GBM. There was intact expression of DNA repair and chromatin remodeling proteins, with accumulation of p53 and reduced MDM2 expression within micronuclei. In contrast, granular mitoses showed pHH3 expression, confirming these cells are undergoing mitotic division, with no accumulation of p53 and reduced expression of DNA repair proteins. Our results emphasize that Creutzfeldt cells are part of the morphologic spectrum of IDH-wildtype glioblastoma. We did not find a role for DNA damage in the generation of Creutzfeldt cells, as both DNA repair and chromatin remodeling protein expression was retained in these cells.

Recurrent Cerebral Hemorrhage in Normal Pregnancy Secondary to Mycotic Pseudoaneurysms Related to Choriocarcinoma.

BACKGROUND: Choriocarcinoma coexisting with or after normal pregnancy is extremely rare. To our knowledge, our case report is the first time cerebral mycotic pseudoaneurysms from choriocarcinoma have been proven angiographically. CASE DESCRIPTION: A 38-week pregnant 26-year-old woman presented with an acute left frontal hemorrhage. She underwent emergency cesarean section, followed by hematoma evacuation and resection of what grossly appeared to be a medium-sized arteriovenous malformation at the time of surgery. Angiogram before and after resection showed no obvious vascular pathology. One month later, she returned with status epilepticus, and an acute parenchymal hematoma posterior to the surgical resection cavity was identified. Angiography showed a multilobulated pseudoaneurysm along the left middle cerebral artery. This was resected and found on histopathology to have choriocarcinoma within and around the blood vessels. Serum human chorionic gonadotrophin levels increased daily. Pan computed tomography showed a left lung lobular mass. The diagnosis was stage 4 World Health Organization score 9 high-risk metastatic choriocarcinoma requiring radiation followed by multiagent chemotherapy. Two weeks later, she had another seizure. An angiogram showed an unruptured pseudoaneurysm along the right posterior cerebral artery, which was embolized. CONCLUSIONS: Metastatic choriocarcinoma is rarely considered during a viable pregnancy but is almost always fatal if unrecognized. Early recognition enhances the chances of cure with chemotherapy. Arteriovenous malformations are typically considered in young women with intracerebral hemorrhages and have higher risk of rupture in pregnant women, but physicians should also be aware of metastatic choriocarcinoma and the development of mycotic aneurysms in peripartum women with intracerebral hemorrhages.

Retrospective Analysis of Molecular and Immunohistochemical Characterization of 381 Primary Brain Tumors.

The classification of brain tumors has traditionally depended on microscopic examination of hematoxylin and eosin-stained tissue sections. The increased understanding of clinically relevant genetic alterations has led to the incorporation of molecular signatures as part of the diagnosis of brain malignancies. Advances in sequencing technologies have facilitated the use of next-generation sequencing (NGS) assays in clinical laboratories. We performed a retrospective analysis of sequencing results for 381 brain tumors tested by NGS at our institution using a validated, commercially available panel. The results of the NGS assay were analyzed in conjunction with the results of immunohistochemical stains. A genetic alteration was detected in approximately two thirds of the cases. The most commonly mutated genes were TP53 (37.2%), IDH1 (29.4%), PIK3CA (8%), PTEN (8%), and EGFR (7.5%). BRAF mutations were detected in ∼3% of the cases, including 50% of gangliogliomas and ∼20% of gliosarcomas. No mutations were detected in 6 medulloblastomas. PIK3CA and CTNNB1 mutations were detected in 1 rosette-forming glioneuronal tumor and 1 adamantinomatous craniopharyngioma, respectively. Approximately 23% of cases showed amplification of 1 or more of the genes included in the NGS panel. This analysis demonstrates the utility of NGS for detecting genetic alterations in brain tumors in the clinical setting.

HER2-Specific Chimeric Antigen Receptor-Modified Virus-Specific T Cells for Progressive Glioblastoma: A Phase 1 Dose-Escalation Trial.

IMPORTANCE: Glioblastoma is an incurable tumor, and the therapeutic options for patients are limited. OBJECTIVE: To determine whether the systemic administration of HER2-specific chimeric antigen receptor (CAR)-modified virus-specific T cells (VSTs) is safe and whether these cells have antiglioblastoma activity. DESIGN, SETTING, AND PARTICIPANTS: In this open-label phase 1 dose-escalation study conducted at Baylor College of Medicine, Houston Methodist Hospital, and Texas Children's Hospital, patients with progressive HER2-positive glioblastoma were enrolled between July 25, 2011, and April 21, 2014. The duration of follow-up was 10 weeks to 29 months (median, 8 months). INTERVENTIONS: Monotherapy with autologous VSTs specific for cytomegalovirus, Epstein-Barr virus, or adenovirus and genetically modified to express HER2-CARs with a CD28.ζ-signaling endodomain (HER2-CAR VSTs). MAIN OUTCOMES AND MEASURES: Primary end points were feasibility and safety. The key secondary end points were T-cell persistence and their antiglioblastoma activity. RESULTS: A total of 17 patients (8 females and 9 males; 10 patients ≥18 years [median age, 60 years; range, 30-69 years] and 7 patients <18 years [median age, 14 years; range, 10-17 years]) with progressive HER2-positive glioblastoma received 1 or more infusions of autologous HER2-CAR VSTs (1 × 106/m2 to 1 × 108/m2) without prior lymphodepletion. Infusions were well tolerated, with no dose-limiting toxic effects. HER2-CAR VSTs were detected in the peripheral blood for up to 12 months after the infusion by quantitative real-time polymerase chain reaction. Of 16 evaluable patients (9 adults and 7 children), 1 had a partial response for more than 9 months, 7 had stable disease for 8 weeks to 29 months, and 8 progressed after T-cell infusion. Three patients with stable disease are alive without any evidence of progression during 24 to 29 months of follow-up. For the entire study cohort, median overall survival was 11.1 months (95% CI, 4.1-27.2 months) from the first T-cell infusion and 24.5 months (95% CI, 17.2-34.6 months) from diagnosis. CONCLUSIONS AND RELEVANCE: Infusion of autologous HER2-CAR VSTs is safe and can be associated with clinical benefit for patients with progressive glioblastoma. Further evaluation of HER2-CAR VSTs in a phase 2b study is warranted as a single agent or in combination with other immunomodulatory approaches for glioblastoma.

Epithelial and organ-related marker expression in pituitary adenomas.

The histologic expression of epithelial and organ-related immunohistochemical markers in primary sellar region tumors has received little attention to date. This lack of empirical data may lead to mistaken assumptions in the evaluation of sellar region neoplasms. To address this issue, the frequency and specificity of epithelial (cytokeratin 7(CK7), CK20) and organ-related differentiation markers (gross cystic disease fluid protein-15 (GCDFP-15), thyroid transcription factor-1 (TTF-1), Napsin A, paired box 8 (PAX-8), hepatocyte paraffin 1 (HepPar1) and estrogen receptor (ER)) were studied in 40 patients with adenomas comprising five hormonal sub-types. Non-parametric statistical procedures were used to examine associations between marker expression and tumor sub-type. CK7 and CK20 immunoreactivity were seen in 48% and 8% of tumors, respectively, although never in a diffuse pattern. CK20 expression was nearly exclusive to corticotrophs, whereas CK7 frequently highlighted cells with dendritic-type morphology. The specificity of organ-related differentiation markers was 100% (monoclonal Napsin A, GCDFP-15 and TTF-1), 97% (HepPar1 and PAX-8), 90% (polyclonal Napsin A) and 72% (ER); no tumors demonstrated significant co-expression of these organ-related markers with either CK7 or CK20. The first major conclusion of this study is that CK7 staining in adenoma is more frequent than has been previously than has been previously described. CK7 immunoreactive cells often displayed a dendritic-type morphology, including within large macroadenomas, which raises the question as to whether these represent tumor cells with folliculo-stellate cell-type differentiation, as these also have dendritic cell-type morphology and express CK7 in non-neoplastic glands. The second major conclusion, which confirms earlier findings, is that CK20 staining is a very infrequent immunohistochemical finding in adenomas that is virtually limited to corticotrophs and thus is helpful in diagnostic confirmation of that sub-type. The final conclusion is in regard to those features that separate adenomas from sellar region metastases: adenomas do not demonstrate significant expression of TTF-1, monoclonal Napsin A, PAX-8, HepPar1 or GCDFP-15, nor do they exhibit diffuse expression of CK7 and CK20.

Suprasellar Primitive Neuroectodermal Tumor in an Adult.

Primitive neuroectodermal tumors (PNET) of the central nervous system (CNS) are a heterogeneous group of embryonal malignancies that are composed of undifferentiated or poorly differentiated neuroepithelial cells. Supratentorial PNET is the second most common CNS embryonal malignancy in children, but it is rare in adults. We report the case of a 31-year-old woman with bilateral vision loss and a bitemporal hemianopia. Neuroimaging revealed a suprasellar mass, and pathology was consistent with PNET. After surgical debulking of the tumor followed by radiation therapy and chemotherapy, the patient had significant visual recovery and remained stable over 14 months of follow-up.

Is CMV a target in pediatric glioblastoma? Expression of CMV proteins, pp65 and IE1-72 and CMV nucleic acids in a cohort of pediatric glioblastoma patients.

While the 5-year overall survival is better in pediatric than in adult patients diagnosed with glioblastoma (GBM), outcomes in children remain very poor. Understanding the mechanisms of tumorigenesis and tumor propagation can identify therapeutic targets to improve these outcomes. Human cytomegalovirus (CMV) proteins and nucleic acids are present in the majority of adult GBM. Indeed, CMV is emerging as a potential glioma-associated target for anti-CMV agents and cellular therapeutics. Furthermore, CMV appears to contribute to GBM's malignant phenotype, although its role in tumorigenesis is less certain. In this cohort of 25 serially diagnosed pediatric GBMs, the largest described cohort to date, we used immunohistochemical staining and in situ hybridization to show the presence of CMV antigens pp65 and IE1-72 as well as CMV nucleic acids, respectively. Our cohort indicated either CMV antigen pp65 or IE1-72 was present in approximately 67 % of pediatric GBM samples. The majority of samples stained positive for either CMV antigen showing a cytoplasmic pattern in 25-50 % of cells within the sample at a moderate intensity, while a few samples showed nuclear staining and higher grade/intensity. Of 16 samples where in situ hybridization was performed, 13 (81 %) showed specific staining using a CMV genome specific probe cocktail. ISH positive samples showed high concordance with being pp65 or IE1-72 positive. These findings, paired with the association of CMV expression with poor prognosis and overall survival, indicate the need to further investigate how these antigens are promoting tumor growth and preventing cell death. Also, the expression of these antigens in a majority of tumor tissues should be considered for immunotherapeutic targets in cases of pediatric GBM.

Recurrent subependymoma of fourth ventricle with unusual atypical histological features: A case report.

Subependymoma is a rare subtype of benign ependymal neoplasm with distinct histological features. Anaplastic transformation has not yet been reported in this tumor to date. We present here a very unusual case of a 62-year-old woman with recurrent subependymoma of the fourth ventricle with multiple atypical histological features. Histologically, the resected recurrent tumor showed characteristic small cell clusters and nests of ependymal cells with an interspersed gliofibrillary matrix as seen in a classic subependymoma. In addition, there were very unusual histological features, including multiple areas of necrosis, microvascular proliferation, thrombosed blood vessels, and scattered mitotic figures. No coexisting ependymoma component of higher World Health Organization (WHO) grade was present. Immunohistochemically, MIB-1 labeling index was high, with up to 15% in the highest areas. Review of this patient's initial tumor, which was resected 6 years prior to recurrence, demonstrated features of a typical classic subependymoma without atypical features or a secondary tumor component. Subependymomas are known to be low-grade tumors and are usually cured if completely excised. The tumor presented here is unique in that several atypical pathological features were found in an otherwise typical subependymoma. Our case may represent anaplastic transformation of subependymoma, although no such examples have been reported to date.

Validation of a novel robotic telepathology platform for neuropathology intraoperative touch preparations.

BACKGROUND: Robotic telepathology (RT) allows a remote pathologist to control and view a glass slide over the internet. This technology has been demonstrated to be effective on several platforms, but we present the first report on the validation of RT using the iScan Coreo Au whole slide imaging scanner. METHODS: One intraoperative touch preparation slide from each of 100 cases were examined twice (200 total cases) using glass slides and RT, with a 3 week washout period between viewings, on two different scanners at two remote sites. This included 75 consecutive neuropathology cases and 25 consecutive general surgical pathology cases. Interpretations were compared using intraobserver variability. RESULTS: Of the 200 total cases, one failed on RT. There were 47 total interpretive variances. Most of these were the result of less specific interpretations or an inability to identify scant diagnostic material on RT. Nine interpretive variances had potentially significant clinical implications (4.5%). Using the final diagnosis as a basis for comparison to evaluate these nine cases, three RT interpretations and three glass slide interpretations were considered to be discrepant. In the other three cases, both modalities were discrepant. This distribution of discrepancies indicates that underlying case difficulty, not the RT technology, probably accounts for these major variances. For the subset of 68 neoplastic neuropathology cases, the unweighted kappa of agreement between glass slides and RT was 0.68 (good agreement). RT took 225 s on average versus only 71 s per glass slide. CONCLUSIONS: This validation demonstrates that RT using the iScan Coreo Au system is a reasonable method for supplying remote neuropathology expertise for the intraoperative interpretation of touch preparations, but is limited by the slowness of the robotics, crude focusing, and the challenge of determining where to examine the slide using small thumbnail images.

Overexpression and constitutive nuclear localization of cohesin protease Separase protein correlates with high incidence of relapse and reduced overall survival in glioblastoma multiforme.

Separase, an enzyme that cleaves the chromosomal cohesin during mitosis, is overexpressed in a wide range of human epithelial cancers of breast, bone and prostate (Meyer et al., Clin Cancer Res 15(8):2703-2710, 2009). Overexpression of Separase in animal models results in aneuploidy and tumorigenesis. We have examined the expression and localization of Separase protein in adult and pediatric glioblastoma and normal brain specimens. Immunofluorescence microscopy and Western blot analysis showed significant overexpression of Separase in all adult and a subset of pediatric glioblastoma cells. Tumor status and patient survival strongly correlate with the mislocalization of Separase into the nucleus throughout all stages of the cell cycle. Unlike exclusively nuclear localization in mitotic control cells, glioblastoma samples have a significantly higher number of resting (interphase) cells with strong nuclear Separase staining. Additionally, patient survival analysis demonstrated a strong correlation between overexpression of Separase protein in adult glioblastoma and a high incidence of relapse and reduced overall survival. These results further strengthen our hypothesis that Separase is an oncogene whose overexpression induces tumorigenesis, and indicate that Separase overexpression and aberrant nuclear localization are common in many tumor types and may predict outcome in some human malignancies.

Necrotizing fasciitis as the initial presentation of disseminated infection with fluconazole-resistant Cryptococcus neoformans.

INTRODUCTION: Cryptococcus neoformans is an encapsulated budding yeast that is a common cause of opportunistic infections, rarely giving rise to cellulitis, vasculitis or fasciitis. Necrotizing fasciitis caused by C. neoformans is a rare but serious problem in post-transplant immunosuppression. CASE PRESENTATION: We report a case of cryptococcal necrotizing fasciitis in the left adductor longus of a patient on immunosuppressive therapy. The patient's medical history was significant for orthotopic heart transplant secondary to cardiac and systemic amyloidosis (AL type) with subsequent cardiac biopsy demonstrating mild rejection (grade 1R). A thigh muscle biopsy demonstrated numerous encapsulated fungi in the fascia and no evidence of myositis. Cryptococcal antigen was subsequently identified in the patient's serum and cerebrospinal fluid. The patient progressed to involvement of the central nervous system, left biceps femoris and skin of the left lower leg by fluconazole-resistant C. neoformans. CONCLUSION: This case illustrates a rare initial presentation of disseminated fluconazole-resistant C. neoformans as an isolated necrotizing fasciitis of the thigh. Necrotizing fungal fasciitis should be considered in immunosuppressed patients with clinical findings of either myositis or cellulitis of a lower extremity.

Brain metastases from papillary thyroid carcinomas.

Brain metastasis from papillary thyroid carcinoma (PTC) is extremely rare and carries a poor prognosis. We report nine cases (five females and four males) of brain metastasis of PTC. The age of patients ranged from 46 to 87 years old. The patients presented with nonspecific symptoms such as headaches. Brain metastasis was the first clinical presentation in three of nine patients; two of which had the aggressive tall cell variant of PTC. Six patients had prior history of PTC (four classic, one oncocytic variant, and one columnar cell variant) for 2 to 17 years with a median of 12 years. Gross total resection of brain metastasis was achieved for eight of our patients. Eight patients were treated with radioactive iodine. The median follow-up time was 12 months, ranging from 1 month to 4 years. Three patients died of their disease in 6 months, 21 months and 4 years, respectively after their first presentation of brain metastasis. It seems that these rare aggressive variants of PTC, such as tall cell variant, not only have higher propensity to develop brain metastasis, but also more frequently present with brain metastasis as their first clinical presentation than classic PTC. Furthermore, patients with PTC can develop brain metastasis even after many years.

Giant cell ependymoma-report of three cases and review of the literature.

Ependymomas constitute the most common type of primary spinal cord tumors, and are subclassified as myxopapillary ependymoma, classic ependymoma, and anaplastic ependymoma. Ependymomas can be further subclassified based on morphologic phenotype: cellular, papillary, tanycytic, clear cell, pigmented and epithelioid. Giant cell ependymoma (GCE), a rare variant, has recently been described. Reported cases have exhibited a wide anatomic distribution, including spinal cord, cerebrum and cerebellum. We report here three cases of GCE, arising from cerebrum in a 5-year-old girl, spinal cord in a 34-year-old female and cerebellum in an 86-year-old female respectively. Histologically those cases showed prominent pleomorphic giant cells with focal perivascular pseudorosettes in all cases. Tumor cells were immunopositive for GFAP and EMA. Only the first case was qualified for anaplastic ependymoma. No recurrence was noted in these three cases after 57, 46 and 6 months of follow-up respectively. By reviewing the literature, GCEs arising from spinal cord and cerebellum tended to have low-grade morphology while supratentorially located GCEs tended to have anaplastic features. GCEs were preferentially located in extraventricular regions. Anaplastic GCEs in adult population seemed to pursue a more aggressive behavior. Gross total resection should still be the main treatment for GCEs.

Isocitrate dehydrogenase 1 R132H mutation is not detected in angiocentric glioma.

Mutations of isocitrate dehydrogenase-1 gene (IDH1), most commonly resulting in replacement of arginine at position 132 by histidine (R132H), have been described in World Health Organization grade II and III diffuse gliomas and secondary glioblastoma. Immunohistochemistry using a mouse monoclonal antibody has a high specificity and sensitivity for detecting IDH1 R132H mutant protein in sections from formalin-fixed, paraffin-embedded tissue. Angiocentric glioma (AG), a unique neoplasm with mixed phenotypic features of diffuse glioma and ependymoma, has recently been codified as a grade I neoplasm in the 2007 World Health Organization classification of central nervous system tumors. The present study was designed to evaluate IDH1 R132H protein in AG. Three cases of AG were collected, and the diagnoses were confirmed. Expression of mutant IDH1 R132H protein was determined by immunohistochemistry on representative formalin-fixed, paraffin-embedded sections using the antihuman mouse monoclonal antibody IDH1 R132H (Dianova, Hamburg, Germany). Known IDH1 mutation-positive and IDH1 wild-type cases of grade II to IV glioma served as positive and negative controls. All 3 patients were male, aged 3, 5, and 15 years, with intra-axial tumors in the right posterior parietal-occipital lobe, right frontal lobe, and left frontal lobe, respectively. All 3 cases showed characteristic morphologic features of AG, including a monomorphous population of slender bipolar cells that diffusely infiltrated cortical parenchyma and ensheathed cortical blood vessels radially and longitudinally. All 3 cases were negative for the presence of IDH1 R132H mutant protein (0/3). All control cases showed appropriate reactivity. IDH1 R132H mutation has been described as a common molecular signature of grade II and III diffuse gliomas and secondary glioblastoma; however, AG, which exhibits some features of diffuse glioma, has not been evaluated. The absence of mutant IDH1 R132H protein expression in AG may help further distinguish this unique neoplasm from diffuse glioma.

Generation of polyclonal CMV-specific T cells for the adoptive immunotherapy of glioblastoma.

Glioblastoma (GBM) is the most common primary brain cancer in adults and is virtually incurable. Recent studies have shown that cytomegalovirus (CMV) is present in majority of GBMs. To evaluate whether the CMV antigens pp65 and IE1, which are expressed in GBMs, could be targeted by CMV-specific T cells, we measured the frequency of T cells targeting pp65 and IE1 in the peripheral blood of a cohort of 11 sequentially diagnosed CMV-seropositive GBM patients, and evaluated whether it was feasible to expand autologous CMV-specific T cells for future clinical studies. All 11 CMV-seropositive GBM patients had T cells specific for pp65 and IE1 in their peripheral blood assessed by IFNγ enzyme-linked immunospot assay. However, the precursor frequency of pp65-specific T cells was decreased in comparison with healthy donors (P=0.001). We successfully reactivated and expanded CMV-specific T cells from 6 out of 6 GBM patients using antigen-presenting cells transduced with an adenoviral vector encoding pp65 and IE1. CMV-specific T-cell lines contained CD4 as well as CD8 T cells, recognized pp65 and IE1 targets and killed CMV-infected autologous GBM cells. Infusion of such CMV-specific T-cell lines may extend the benefits of T-cell therapy to patients with CMV GBMs.