Expressions of aquaporin-2, vasopressin type 2 receptor, transient receptor potential channel vanilloid (TRPV)1, and TRPV4 in the human endolymphatic sac.

OBJECTIVE: To localize aquaporin (AQP)2, vasopressin type 2 receptor (V2-R), and transient receptor potential channel vanilloid subfamily 1, 4 (TRPV1, TRPV4) in the human endolymphatic sac (ES). METHODS: Three samples of human ES were sampled during the removal of vestibular schwannoma by way of the translabyrinthine approach. The samples were immediately fixed in 4% paraformaldehyde and embedded in OCT compound; immunohistochemistry was performed with AQP2, V2-R, TRPV1, and TRPV4 polyclonal antibodies. RESULTS: AQP2, V2-R, TRPV1, and TRPV4 proteins were detected in the epithelial layer of the ES but were not observed in connective tissue around the ES. TRPV1 was also expressed in blood vascular endothelial cells of the connective tissue of ES. CONCLUSIONS: AQP2, V2-R, and TRPV4 were expressed in the luminal epithelium of human ES. The same characteristic distribution of water and ion channels is seen in the kidney, where a significant amount of fluid is filtrated and resorbed. ES probably plays an active role in the homeostasis of the endolymph.

Primary cultures of human vestibular schwannoma: selective growth of schwannoma cells.

OBJECTIVE: To establish primary vestibular schwannoma (VS) cultures that selectively favor the growth of schwannoma cells. BACKGROUND: The lack of a suitable in vitro model of human VS cells has directly limited the progress of research on tumorigenesis and therapy. The problems of establishing pure VS culture include control of fibroblast proliferation. Current efforts to extend VS cell life span using viral oncogenes, by conferring the ability to proliferate in vitro, will yield cells intrinsically different from in vivo VS tumors. Much more desirable is the ability to culture VS cells without cellular transformation. METHODS: Tumor specimens from 17 patients were processed for cell culture and grown at 37 degrees C with 5% CO2 and 100% humidity. Key modifications limiting fibroblast proliferation included using selective medium without L-valine, supplemented by Nu-Serum for at least a week; the use of cytosine arabinoside to kill contaminating fibroblasts; and using the Dulbecco modified medium, supplemented with brain-derived neurotrophic factor and 10% fetal calf serum after the initial serum-free period. RESULTS: Twelve of 17 VS were successfully cultured. The presence of schwannoma cells and the absence of fibroblasts were confirmed immunohistochemically using S100 and CD90 markers, respectively. Scanning and transmission electron microscopy demonstrated typical spindle-shaped cells and the presence of "fibrous long-spacing collagen." CONCLUSION: We describe a method for obtaining short-term, essentially fibroblast-free, primary VS cultures. Such pure VS cultures, retaining in vivo characteristics, are extremely useful as an in vitro model to study the pathobiology of schwannoma cells.

Cyclin D(1) and D(3) expression in vestibular schwannomas.

OBJECTIVES: The G1 regulators of the cell cycle, cyclin D(1) and D(3), have been implicated in the regulation of Schwann cell proliferation and differentiation. The purpose of this study is to evaluate cyclin D(1) and D(3) protein expression and the corresponding clinical characteristics of vestibular schwannomas. STUDY DESIGN AND METHODS: Tissue sections of 15 sporadic vestibular schwannomas were prepared. Immunohistochemical analysis of the vestibular schwannomas was performed with anticyclin D(1) and anticyclin D(3) antibodies. The immunoreactivity was evaluated in comparison with adjacent vestibular nerves. Tissue sections of breast carcinoma and prostate carcinoma were used as positive controls for cyclin D(1) and D(3) staining, respectively. Patient demographics, tumor characteristics, and cyclin D expression were reviewed, and statistical analysis was performed. RESULTS: While the breast carcinoma control expressed abundant cyclin D(1) protein, none of the 15 vestibular schwannomas showed detectable cyclin D(1) staining. In contrast, seven of 15 vestibular schwannomas stained positive for the cyclin D(3) protein. Cyclin D(3) staining was taken up in the nucleus of schwannoma tumor cells in greater proportion than Schwann cells of adjacent vestibular nerve. Although sample size was small, no significant difference in the average age of presentation, tumor size, and male to female ratios for the cyclin D(3)(+) or cyclin D(3)(-) groups was found. CONCLUSION: The Cyclin D(1) protein does not appear to play a prominent role in promoting cell cycle progression in vestibular schwannomas. In contrast, cyclin D(3) expression was seen in nearly half of the tumors examined, suggesting that it may have a growth-promoting role in some schwannomas. Further studies are needed to define its cellular mechanism.

Growth of postoperative remnants of unilateral vestibular nerve schwannoma: role of the vestibular ganglion.

Histopathological examination of seven temporal bones from patients who underwent a removal of vestibular nerve schwannomas by the translabyrithine or middle fossa approaches has demonstrated small tumor remnants that failed to grow as long as 25 years after surgery. In spite of the high incidence of residual tumors, the clinical recurrence rate of tumors operated at our institution by the translabyrinthine or middle fossa approaches is low (0.3%). Immunohistochemical labeling of dividing cells demonstrated that segments of tumor adjacent to the vestibular nerve and ganglion contained more dividing cells than were present in areas of the tumor at a distance from them.

Calcified vestibular schwannoma with unusual histological characteristics - positive immunoreactivity for CD-34 antigen.

Calcification in vestibular schwannoma is extremely rare. A 36-year-old man presented with a history of decreased hearing on the left since childhood. Computed tomography showed a left cerebellopontine angle lesion protruding into the porus acousticus and enlarging the internal auditory meatus, with significant deposits of calcification. Histological and immunohistochemical examination, including staining for CD-34, a myeloid progenitor cell antigen, found highly degenerated schwannoma with collagen-rich tissue, calcification, formation of bone, abnormal vessels of various sizes, and old haemorrhage with marked haemosiderin-laden macrophages. Most of the surgical specimen was sclerotic collagenous tissue containing sparse spindle-shaped cells which formed approximately 90% of the total specimen. However, the spindle-shaped cells were partly concentrated into islands forming the cellular part (approximately 10% of the total). The spindle-shaped cells in both parts showed almost typical immunohistochemical characteristics of schwannoma. However, many spindle-shaped cells in only the sclerotic part were positive for CD-34, which is widely used for the diagnosis of solitary fibrous tumours. Cerebellopontine angle tumour showing fibromatous tissue, including calcification, may contain foci of typical schwannoma. Careful histological examination with detailed immunohistochemical staining is required for the correct diagnosis. In particular, spindle-shaped cells occasionally show positive immunoreactivity for CD-34 antigen in the areas of degenerated and calcified schwannoma characteristic of our case.

History of allergies and autoimmune diseases and risk of brain tumors in adults.

To explore a possible influence of the immune system in the development of brain tumors, we evaluated the relationship between history of allergies and autoimmune diseases and risk of brain tumors within a large, hospital-based case-control study. Cases (n = 782) were patients recently diagnosed with glioma (n = 489), meningioma (n = 197) or acoustic neuroma (n = 96) at hospitals in Boston, Phoenix and Pittsburgh (USA). Controls (n =799) were patients hospitalized for a variety of nonmalignant conditions and frequency-matched to cases by hospital, age, sex, race/ethnicity and distance of residence from hospital. Research nurses collected data by personal interview of patients. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression. There was a significant inverse association between glioma and history of any allergies (OR = 0.67, 95% CI = 0.52-0.86) or autoimmune diseases (OR = 0.49, 95% CI = 0.35-0.69). No significant associations were evident for meningioma or acoustic neuroma with history of any allergies. An inverse association was observed between meningioma and history of autoimmune diseases (OR = 0.59, 95% CI = 0.38-0.92). There was a suggestion of interaction between allergies and autoimmune diseases on risk of glioma (p = 0.06), with subjects having both conditions being at lowest risk (OR = 0.24, 95% CI = 0.14-0.42). Among the specific conditions, asthma and diabetes showed the most consistent associations (OR = 0.63, 95% CI = 0.43-0.92 and OR = 0.44, 95% CI = 0.27-0.70, respectively). Our results add to evidence that persons with allergies or autoimmune diseases are at reduced risk of glioma. The basis of the associations is not clear, but they might imply a role of immunologic factors in the development of brain tumors. Published 2002 Wiley-Liss, Inc.

Detection of antibody to sialyl-i, a possible antigen in patients with Meniere's disease.

An autoimmune hypothesis for the etiology of Meniere's disease has been proposed. In this study, we focused on gangliosides as potential antigens for autoantibodies in Meniere's disease patients. In an attempt to investigate ganglioside antigens which respond to the serum of patients with Meniere's disease, we analyzed gangliosides of human acoustic neurinomas, and used them as antigens to broadly explore gangliosides that react to serum. All the acoustic neurinoma samples used in the present study showed a similar ganglioside profile on TLC (thin-layer chromatography). For the microscale ganglioside analysis, a newly developed TLC blotting/secondary ion mass spectrometry (SIMS) system together with TLC immunostaining method was employed. Most of the ganglioside bands could be analyzed, and they were identified as GM3, GM2, SPG, GM1a, GD3, S-i (sialyl-i ganglioside) and GD1a. GD1a was the predominant ganglioside and many neolactoseries gangliosides were recognized by immunological analysis. Next, the immune reactivity of serum samples, from patients with Meniere's disease, with the acoustic neurinoma gangliosides was studied by TLC immunostaining. The result showed that five of 11 patients with Meniere's disease and one of eight normal subjects reacted with a specific band, which was identified as S-i by the TLC blotting/SIMS system. The findings of the present study indicate that S-i ganglioside is an autoantigen and possibly involved in the pathogenesis of Meniere's disease.

Serum immunoglobulins in brain tumours and lumbar disc diseases.

Changes of serum immunoglobulin (Ig) concentrations may occur in both brain tumours and lumbar disc diseases (LDD). The purpose of this study was to investigate the changes of pre- and post-operative serum Ig levels in brain tumours and LDDs. Serum IgG, IgA and IgM levels were measured in 127 patients with brain tumour, 100 patients with LDD and 20 healthy subjects without neurological disease. Increases in one or more of the pre-operative serum Ig levels were observed in the patients with both brain tumours and LDDs compared with controls. However pre-operative serum IgG level was highly increased in all brain tumour types and LDDs (p<0.001). Serum IgA levels and IgM levels in the post-operative stage were significantly decreased in patients with acoustic neurinoma (p<0.01, p<0.001, respectively). Post-operative serum IgG, IgA and IgM levels were significantly decreased (p<0.001) in patients with meningioma. Post-operative serum IgG and IgM levels were significantly decreased (p<0.001) in patients with glioma. Patients with LDD showed a significantly decline in post-operative serum IgA and IgM levels (p<0.001). We think that decline in post-operative serum Ig levels may be of prognostic value in the patients with brain tumours and LDDs.

A study of vestibular schwannomas using positron emission tomography and monoclonal antibody Ki-67.

OBJECTIVE: This study aimed to evaluate the role of positron emission tomography (PET) as an in vivo determinant of tumor aggressiveness and growth. STUDY DESIGN: The study design was a prospective pilot study. SETTING: Positron emission tomography was performed at the Clarke Institute of Psychiatry. All patients were treated at the Sunnybrook Health Science Centre. Both institutions are affiliated with the University of Toronto, Toronto, Canada. PATIENTS: The study consisted of five consecutive patients with vestibular schwannomas with tumor size of 1 cm or larger within the cerebellopontine angle. One was a recurrent tumor and four were primary tumors. INTERVENTIONS: Preoperative PET studies were conducted using 18-fluorodeoxyglucose (FDG) as a radionuclide tracer to measure glucose metabolism within tumors. Tumors were processed and immunostained against Ki-67 nuclear antigen; their proliferative potentials were quantified based on immunoreactivity of tumor cells. MAIN OUTCOME MEASURES: Tumor metabolic activity on PET was compared with that of contralateral cerebellum to arrive at an FDG index. This number was compared with clinical parameters and Ki-67 reactivity. RESULTS: On PET, all tumors showed less metabolic activity than the cerebellum. The FDG uptake varied greatly between tumors independent of clinical parameters. All the tumors had a low proliferative index (<5%) with immunohistochemistry; there were quite a bit of intralesional variations in proliferative activities. CONCLUSION: Large tumor size and recurrent disease did not correlate well with increased FDG uptake on PET. Similarly, they did not show increased cellular activities as expressed by Ki-67 immunostaining.

[A system of individual immunotherapy with leakadin in the combined therapy of acoustic neurinomas]. / Sistema individual'noi immunoterapii leakadinom v kompleksnoi terapii nevrinom slukhovogo nerva.

Analyzing the immunological responsiveness of patients with acoustic neurinomas on the antitumor immunomodulator leacadin has revealed some significant features. In leacadin-treated patients, postimmunotherapy promotes the formation of high sanogenetic responses: an increase in the rigidity of the brain-immune system; elevations of the levels of antitumor factors of the immune system: T helper cells and locally synthesized antibodies; a decrease in neuro-sensitization after tumor removal, which prevents tumor stimulation and recurrence; an indirect reduction in the activity of T suppressors that inhibit immunological responses in growing neoplasm. Immunotherapy with the antitumor immunomodulator leacadin in patients with acoustic neurinomas contributes to the development and optimization of the tumor carrier's immunological adaptative responses, creates conditions for the optimal postoperative course and prevents recurrence.

Proliferation indices of vestibular schwannomas by Ki-67 and proliferating cell nuclear antigen.

Two immunohistologic demonstrations of markers of proliferating cells, Ki-67 and proliferating cell nuclear antigen, were applied to tissues from 10 vestibular schwannomas. Each method demonstrated three distinct rates of positively stained cells (p < .01 and p < .015, respectively, for each method). There was a one-to-one correspondence between the two immunohistologic methods in the assignment of cases to each growth rate category except for two cases (Spearman rank correlation r = 0.76, p < .05). These data support the concept of distinct growth rates in vestibular schwannoma. Tissues were also sampled from different areas of the same tumor within nine samples. The results suggest that tumor growth is not homogeneous within a tumor, but that proliferation may be more active near the surface.

Clinicopathologic growth factors of acoustic neuromas.

BACKGROUND Understanding the tumor growth rate is very important when considering strategies for the treatment of an acoustic neuroma, although the natural course of acoustic neuromas has not been reviewed in detail. METHODS The clinicopathologic features and the postoperative growth of tumors were evaluated in 32 patients with acoustic neuromas. This study was undertaken to assess the variability of the growth potential of cells within an acoustic tumor and to determine the relationships between the growth rate and the clinicopathologic characteristics of the patients with acoustic neuromas, including age at surgery, gender, tumor location and preoperative size, the duration of the symptoms, the presence of cystic regions, the presence of Antoni type A and B cells, the tumor cell density, tumor vascularity, mitotic rate, the presence of hyaline degeneration and hemosiderin deposition, nucleolar organizer regions (NORs), and the level of proliferating cell nuclear antigen (PCNA). RESULTS The growth patterns of the tumors were divided into three groups according to their growth rate: a regression group, a "no-growth" group (growth rates from 0-0.11 cm/year) and a progression group (growth rates from 0.19-1.72 cm/year). An additional operation was required in all patients whose growth rate was more than 0.38 cm/year. A statistical study on the factors associated with an increased growth rate showed that the three histopathologic factors most significantly associated with a postoperative growth rate were hyaline degeneration (p < 0.05), cell density (p < 0.005), and PCNA labeling index (p < 0.005). CONCLUSIONS These results strongly suggest that acoustic tumors can be subdivided into several groups, based upon different biologic activities and tumor growth rates.

Circulating immune complexes in intracranial neoplasms.

The levels of circulating immune complexes (CIC) were assayed in the sera of 109 patients with intracranial space occupying lesions. The CIC levels were significantly increased in all the brain tumours. After treatment, the CIC levels were still significantly increased when compared to the controls but showed no change when compared to their respective pre-operative values. Further, no change was observed in the CIC levels between the malignant and benign tumour case. Moreover, in brain tumours, 90% of the CIC precipitate consisted of IgG. However, the CIC levels fail to prognosticate the process of the disease in these patients.

[Immunotherapy with leakadin in the combined therapy of acoustic neurinomas]. / Immunoterapiia leakadinom v kompleksnoi terapii nevrinom slukhovogo nerva.

The paper reports the data obtained on the efficacy of a new anti-cancer immunomodulator leacadin in neurinoma of the acoustic nerve. Leacadin participates in formation of a close regulatory relation between the brain and immune system, promotes centralization of immunity regulation in conditions of surgical trauma. The drug can also increase the level of natural killers and helpers, reduce neurosensitization and the amount of suppressors.

[Leakadin immunotherapy in the combined therapy of acoustic neurinomas]. / Immunoterapiia leakadinom v kompleksnoi terapii nevrinom slukhovogo nerva.

The paper specifies the role of leacadin immunotherapy in combined treatment of acoustic nerve neurinomas. The antitumor immunomodulator leacadin contributes to establishment and consolidation of the tumor carrier's immunological adaptation which results in uneventful postoperative developments and recurrent-free survival.

Growth rate of acoustic neuroma expressed by Ki-67 nuclear antigen versus symptom duration.

The growth rate of acoustic tumors varies widely. An immunohistochemical study with Ki-67 monoclonal antibody was performed on a random sample of 21 acoustic neuromas. The tumors belonged to 2 well-defined groups: 1 with a short duration of preoperative symptoms (< 1 year) and 1 with a long duration of preoperative symptoms (> 5 years). The tumors were of small to medium size (7 to 27 mm), and no large, cystic, or Recklinghausen tumors were included. The tumor proliferative fraction expressed by monoclonal antibody Ki-67 was determined. The results revealed a significant relation between the tumor proliferative fraction and symptom duration. Tumors with a high proliferative status had a short preoperative symptom duration, while tumors with a low proliferative status had a long symptom duration. The clinical implications of these results are discussed.

Serum adenosine deaminase activity in brain tumours.

Adenosine deaminase (ADA) activity in serum was estimated in 86 patients with intracranial tumours and 40 healthy volunteers. Although high ADA concentrations in biological fluids and tumour tissues were observed in several neoplastic conditions, there was no significant difference in the ADA in sera of brain tumour patients when compared to the control values. Therefore, cell-mediated immunity probably does not play a significant role in brain tumours.

Serum immunoglobulins in brain tumours.

Immunoglobulin level in the sera of 62 patients with intracranial space occupying lesions was assayed using the radial immunodiffusion method. Serum IgM levels showed a highly significant increase in all types of brain tumour when compared to controls. Serum IgG levels were also increased in benign as well as malignant cases. Serum IgA levels were high only in benign cases. Hence, increased serum Ig levels may be of prognostic value in these cases.