Abstract LB-055: Novel therapeutic option targeting the tumor cell lysosomes

Malignant brain tumors represent a surgical and therapeutic challenge. Despite major breakthrough in the precision neurosurgery and the personalized medicine, it remains impossible to circumvent the tumor relapse. This is due to the highly infiltrative nature of the glioma cells, with single tumor-initiating cells invading far distances in the brain. However, we recently identified a major flaw in the invasive tumor cell biology: a high sensitivity to the lysosomal membrane permeabilization (LMP). We first identified the fatty acid binding-protein 3 (FABP3) specifically expressed by invasive gliomas cells. Expression of FABP3 is indispensable to the transportation of poly-unsaturated fatty acids (PUFAs), which cannot be otherwise synthetized by the cells, from the extracellular space to biological membranes. Silencing of FABP3 stopped the supply of PUFAs that are essential to the lysosomal membrane maintenance. Induction of the LMP activated a cascade of events including the release of the lysosomal cathepsins in the cytosol, leading to the tumor cell death. Interestingly, the specific killing of invasive glioma cells through the LMP can be achieved by using lysosomotropic drugs, such as anti-histamines. These cationic amphiphilic molecules accumulate in the lysosome and induce the phospholipidosis of the lysosomal membrane. We therefore tested the ability of the blood-brain-barrier permeable clemastine, an anti-histamine, to reduce the tumorigenicity several patient-derived gliomas implanted in nude mice. Although clemastine treatment did not modify the primary tumor mass growth, it completely eradicated the invasive population. These promising results obtained by therapeutic activation of the LMP could also be beneficial for other aggressive cancers models, such as brain metastases of breast cancer or metastatic pancreatic cancer.

Citation Format: Vadim Le Joncour, Pauliina Filppu, Minna Holopainen, Maija Hyvönen, S. Pauliina Turunen, Harri Sihto, Isabel Burghardt, Juha Jääskeläinen, Michael Weller, Kaisa Lehti, Reijo Käkela, Pirjo Laakkonen. Novel therapeutic option targeting the tumor cell lysosomes [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-055.

Vulnerability of invasive glioblastoma cells to lysosomal membrane destabilization

The current clinical care of glioblastomas leaves behind invasive, radio‐ and chemo‐resistant cells. We recently identified mammary‐derived growth inhibitor (MDGI/FABP3) as a biomarker for invasive gliomas. Here, we demonstrate a novel function for MDGI in the maintenance of lysosomal membrane integrity, thus rendering invasive glioma cells unexpectedly vulnerable to lysosomal membrane destabilization. MDGI silencing impaired trafficking of polyunsaturated fatty acids into cells resulting in significant alterations in the lipid composition of lysosomal membranes, and subsequent death of the patient‐derived glioma cells via lysosomal membrane permeabilization (LMP). In a preclinical model, treatment of glioma‐bearing mice with an antihistaminergic LMP‐inducing drug efficiently eradicated invasive glioma cells and secondary tumours within the brain. This unexpected fragility of the aggressive infiltrating cells to LMP provides new opportunities for clinical interventions, such as re‐positioning of an established antihistamine drug, to eradicate the inoperable, invasive, and chemo‐resistant glioma cells from sustaining disease progression and recurrence.

Relative Heart Volume and Subsequent Mortality in Old People

In 1971 radiologic heart volume was measured in 721 men and women over the age of 65 as part of a cardio-respiratory screening examination in a rural community in Central Finland. The survival time for the whole series examined was followed for up to ten years. Relative heart volume did not differ between the sexes, but it increased with age in both men and women. The relative heart volume of almost every second woman exceeded 450 ml/m2, whereas in men it exceeded 500 ml/m2 in only every fifth. These limits have often been considered appropriate for the respective sexes. There was an inverse correlation between relative heart volume and survival time. A large relative volume predicted excess mortality due to cardiovascular diseases. A small relative heart volume predicted excess mortality attributable to tumours and respiratory diseases.

Association of plasma fatty acid composition with plasma irisin levels in normal weight and overweight/obese children

BACKGROUND

Irisin has been suggested to protect against overweight. There are no previous data on the association of plasma fatty acid (FA) composition with plasma irisin.

OBJECTIVES

We studied the association of FA composition with plasma irisin in normal weight and overweight/obese children.

METHODS

This cross-sectional study included pre-pubertal children (388 normal weight children and 55 overweight/obese children); 6-9 years of age, taking part in the Physical Activity and Nutrition in Children Study. After an overnight fast, we measured plasma FA composition by gas chromatography and plasma irisin levels by enzyme-linked immunosorbent assay.

RESULTS

Higher proportion of total monounsaturated fatty acids in plasma cholesteryl esters (CEs) (β = 0.139, P = 0.003) and phospholipids (PLs) (β = 0.147, P = 0.002) and lower proportion of total polyunsaturated fatty acids in plasma CE (β = -0.130, P = 0.006) and PL (β = -0.165, P < 0.001) were associated with higher plasma irisin level in the whole study group. The association of plasma FA composition with plasma irisin level was stronger among overweight/obese children compared to normal weight children. Higher proportion of γ-linolenic acid (β = 0.324, P = 0.017) and lower proportion of linoleic acid (β = -0.397, P = 0.005) in plasma CE were related to higher plasma irisin level among overweight/obese children, indicating the direct association of estimated D6D activity in plasma CE (β = 0.343, P = 0.011) with plasma irisin. Furthermore, higher proportion of oleic acid in plasma CE (β = 0.345, P = 0.012) and PL (β = 0.292, P = 0.033) and higher proportion of adrenic acid (β = 0.366, P = 0.008) and docosapentaenoic acid (β = 0.351, P = 0.010) in plasma PL were associated with higher plasma irisin level among overweight/obese children.

CONCLUSION

Metabolically unfavourable plasma FA profile was associated with higher plasma irisin level especially in overweight/obese children, suggesting that excess body fat might modulate these relationships.

Characteristics of Posterior Cerebral Artery Aneurysms

BACKGROUND:

Posterior cerebral artery (PCA) aneurysms are rare lesions. Because of their low incidence, the individual or institutional experience is usually limited.

OBJECTIVE:

To identify specific anatomic features related to PCA aneurysms based on the analyses of pretreatment angiograms.

METHODS:

We performed a detailed angiographic study of 81 patients with a diagnosis of 93 PCA aneurysms. Fifty-three patients underwent computed tomography angiography, 49 underwent digital subtraction angiography, and 6 underwent magnetic resonance angiography. Between 1980 and 2012, a total of 120 patients with 136 PCA aneurysms and 11 352 patients with 16 444 intracranial aneurysms were treated at our institutions.

RESULTS:

There were 29 ruptured and 64 unruptured PCA aneurysms. The distribution of the aneurysms along the PCA segments was P1 (n = 39; 9 ruptured), P1/P2 junction (n = 25; 9 ruptured), P2 (n = 21; 5 ruptured), and P3 (n = 8; 6 ruptured). The median aneurysm size was 7 mm for the ruptured and 4 mm for the unruptured aneurysms. Saccular aneurysms (n = 69, 74%) had a typical projection for each location: P1 segment, upward (67%); P1/P2 junction, anterior/upward (80%); P2 segment, lateral (67%); and P3 segment, posterior (50%). Multiple aneurysms were seen in 43 patients. PCA aneurysms related to arteriovenous malformations were observed in 10 patients.

CONCLUSION:

PCA aneurysms are infrequent lesions, often associated with multiple aneurysms and arteriovenous malformations and are fusiform in shape. Most ruptured PCA aneurysms are smaller than 10 mm and usually distally located. At each PCA segment, saccular PCA aneurysms have a typical dome orientation.

Serum glucocorticoids and adiponectin associate with insulin resistance in children born small for gestational age

OBJECTIVES

Altered glucocorticoid activity is one possible mechanism linking fetal growth restriction with later insulin resistance (IR) and type 2 diabetes. We aimed to investigate whether serum glucocorticoid parameters are related to IR in children born small for gestational age (SGA).

DESIGN

A total of 110 children (55 age- and gender-matched pairs born SGA or appropriate for gestational age (AGA) in a case-control setting) were studied at the mean age of 12.2 (s.d. 0.2) years.

METHODS

Serum cortisol, corticosteroid-binding globulin (CBG), free cortisol index (FCI=cortisol/CBG), and glucocorticoid bioactivity (GBA, transactivation assay) were analyzed and related to serum adiponectin and insulin-like growth factor-binding protein 1 (IGFBP1) concentrations and homeostasis model assessment for IR (HOMA-IR) and QUICKI indices.

RESULTS

In the pooled study population, GBA correlated well with cortisol and FCI (r=0.681 and 0.586 respectively; P<0.001 for both). Serum cortisol, CBG, FCI, GBA, HOMA-IR, or QUICKI did not differ between the SGA and AGA subjects, but the SGA children had lower body mass index (P=0.005) and waist circumference (WC) (P=0.001). The mean GBA in the highest GBA quartile was higher among the SGA subjects than among the AGA subjects (138.6 vs 96.4 nmol/l cortisol equivalents, P<0.001). In the SGA children, GBA correlated positively with HOMA-IR (r=0.522, P<0.001) and inversely with adiponectin (r=-0.278, P=0.042) (WC/height ratio adjustments), and in logistic regression analysis, higher GBA (odds ratio (OR) 1.3; P=0.013), lower adiponectin (OR 1.4; P=0.038), and lower IGFBP1 (OR 1.9; P=0.010) associated independently with higher HOMA-IR.

CONCLUSIONS

These findings suggest that increased glucocorticoid activity and low serum adiponectin concentrations associate with IR in SGA children.

Autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy (APECED)--a diagnostic and therapeutic challenge

Autoimmune polyendocrinopathy - candidosis - ectodermal dystrophy (APECED), also known as autoimmune polyendocrine/polyglandular syndrome type 1 (APS1), is a rare disease caused by mutations in the autoimmune regulator (AIRE) gene pair resulting in absence of active AIRE protein, which is essential for both central and peripheral self-tolerance. The phenotype is widely variable. Apart from the classical triad of mucocutaneous candidosis, hypoparathyroidism and adrenal failure, several other components, some of which are potentially life-threatening, may develop. Due to the unpredictable clinical course, the patients need regular follow-up by a clinician familiar with the disease. Diagnosis is often possible by clinical diagnostic criteria, but in many cases the early clinical picture does not bring it to mind. A novel tool, search for autoantibodies against interferon-omega, enables proof or exclusion of APECED with more certainty than gene analysis. It is highly specific and sensitive for APECED if thymoma and myasthenia gravis are excluded.

LATERAL SUPRAORBITAL APPROACH APPLIED TO OLFACTORY GROOVE MENINGIOMAS

OBJECTIVE

The lateral supraorbital approach for safely and completely removing olfactory groove meningiomas was assessed.

METHODS

Between September 1997 and June 2008, a total of 656 meningiomas were operated on by the senior author (JH) at the Department of Neurosurgery, Helsinki University Central Hospital; 66 were olfactory meningiomas. We retrospectively analyze the clinical data, radiological findings, surgical treatment, histology, and outcome of all the olfactory groove meningioma patients and discuss the operative techniques used.

RESULTS

Sixty-six patients were operated on by the lateral supraorbital approach. The median preoperative Karnofsky Performance Scale score was 80 (range, 40–100). Three patients were redo cases in which the primary operation had been performed elsewhere. Seemingly complete tumor removal was achieved in 60 patients (91%); there was no surgical mortality. Postoperatively, 6 patients (9%) had cerebrospinal fluid leakage, 5 (8%) had new visual deficits, 4 (6%) had wound infections, 4 (6%) had cotton granulomas, and 1 (2%) had a postoperative hematoma. The median Karnofsky score at discharge was 80 (range, 40–100). Six patients had recurrent tumors; 3 underwent reoperations after an average of 21 months (range, 1–41 months); 1 was treated with radiosurgery, and 2 were only followed. During the median follow-up time of 45 months (range, 2–128 months), there were 4 recurrences (6%) diagnosed on average 32 months (range, 17–59 months) after surgery.

CONCLUSION

The lateral supraorbital approach can be used safely for olfactory groove meningiomas of all sizes with no mortality and relatively low morbidity. Surgical results and tumor recurrence with this fast and simple approach are similar to those obtained with more extensive, complex, and time-consuming approaches.

WNT-4 mRNA expression in human adrenocortical tumors and cultured adrenal cells

The members of the Wnt glycoprotein family are important in embryogenesis and adult tissue homeostasis, and deletion of WNT-4 gene in mice leads to improper development of many organs including the adrenals. The objective of this study was to investigate the expression of WNT-4 gene in human adrenals and adrenocortical tumors. The WNT-4 mRNA expression (analyzed by quantitative real-time RT-PCR) was significantly higher in Conn's adenomas (p<0.01) and lower in Cushing's adenomas, virilizing carcinomas and fetal adrenals (p<0.05) compared with normal adult adrenals. WNT-4 mRNA expression was clearly upregulated by ACTH and 8-bromo-cAMP (8-BrcAMP) in primary cultures of normal adult adrenocortical cells, but downregulated by 8-BrcAMP and 12- O-tetradecanoylphorbol-13-acetate (TPA) in human NCI-H295R adrenocortical carcinoma cells. Angiotensin II tended to increase WNT-4 mRNA expression at 24 hours and decreased it at 48 hours time point in both cell culture types. The abundant WNT-4 mRNA expression in Conn's adenomas and its hormonal regulation in adrenocortical cells suggest a role for WNT-4 in human adrenocortical function.

A novel mutation in the human androgen receptor suggests a regulatory role for the hinge region in amino-terminal and carboxy-terminal interactions

CONTEXT

The androgen insensitivity syndrome (AIS) is caused by molecular defects in the androgen receptor (AR). Clinically, the partial AIS has a variable phenotype. Many mechanisms explain the phenotype in the AIS. A crucial step in AR action is the interaction of the N and C termini.

OBJECTIVE

The role of the hinge region of the AR is not as well understood as other parts of the receptor. We aim to study the role of this region in the N/C-termini interaction.

PATIENT AND METHOD

We report a patient with severe undermasculinization and poor response to exogenous androgens. Androgen binding was performed, and the AR gene was sequenced. The mutation was recreated and transfected in COS-1 cells. Transactivation was studied. N/C-termini interaction was studied using a mammalian two-hybrid assay. A nuclear localization study was performed.

RESULTS

Androgen binding was normal, and a novel mutation (Arg629Trp) in the AR hinge region was identified. Mutant AR transactivation was 40% higher compared with wild type (WT). A 3-fold increase in transcription occurred when both WT N and C-terminal domains were cotransfected; no response occurred when the mutated region of the AR was included (P < 0.001). Cells with mutant AR showed a comparable nuclear localization to the WT AR.

CONCLUSIONS

A mutation in the hinge region impaired N/C-domain interaction in the presence of normal AR binding and nuclear localization. It resulted in severe undermasculinization at birth and resistance to androgens. The findings confirm a unique regulatory role for the hinge region in AR function.

Microneurosurgical management of aneurysms at the A2 segment of anterior cerebral artery (proximal pericallosal artery) and its frontobasal branches

BACKGROUND

Aneurysms originating from the A2 segment of ACA and its frontobasal branches are rare, forming less than 1% of all IAs. There are only few reports on management of A2As. In this article, we review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of A2As.

METHODS

This review, and the whole series on IAs, is mainly based on the personal microneurosurgical experience of the senior author (JH) in two Finnish centers (Helsinki and Kuopio), which serve, without patient selection, the catchment area in Southern and Eastern Finland.

RESULTS

These two centers have treated more than 10000 patients with IAs since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients and 4253 IAs, there were 35 patients carrying 35 A2As, forming 1% of all patients with IAs, 0.8% of all IAs, and 3% of all ACA aneurysms. Twenty-one (60%) patients presented with ruptured A2As with ICH in 11 (52%) and IVH in 7 (33%). Nineteen patients (54%) had multiple aneurysms.

CONCLUSIONS

A2As are often small, even when ruptured, with relatively wide base, and they are frequently associated with ICHs of IVHs. Our data suggest that A2As rupture at smaller size than IAs in general. The challenge is to select appropriate approach, locate the aneurysm deep inside the interhemispheric fissure, and to clip the neck adequately without obstructing branching arteries at the base. Unruptured A2As also need microneurosurgical clipping even when they are small.

Incidence of gliomas by anatomic location

The anatomic location of a glioma influences prognosis and treatment options. The aim of our study was to describe the distribution of gliomas in different anatomic areas of the brain. A representative population-based sample of 331 adults with glioma was used for preliminary analyses. The anatomic locations for 89 patients from a single center were analyzed in more detail from radiologic imaging and recorded on a three-dimensional 1 x 1 x 1-cm grid. The age-standardized incidence rate of gliomas was 4.7 per 100,000 person-years. The most frequent subtypes were glioblastoma (47%) and grade II-III astrocytoma (23%), followed by oligodendroglioma and mixed glioma. The gliomas were located in the frontal lobe in 40% of the cases, temporal in 29%, parietal in 14%, and occipital lobe in 3%, with 14% in the deeper structures. The difference in distribution between lobes remained after adjustment for their tissue volume: the tumor:volume ratio was 4.5 for frontal, 4.8 for temporal, and 2.3 for parietal relative to the occipital lobe. The area with the densest occurrence was the anterior subcortical brain. Statistically significant spatial clustering was found in the three-dimensional analysis. No differences in location were found among glioblastoma, diffuse astrocytoma, and oligodendroglioma. Our results demonstrate considerable heterogeneity in the anatomic distribution of gliomas within the brain.

NO LONG-TERM EXCESS MORTALITY IN 280 PATIENTS WITH RUPTURED DISTAL ANTERIORCEREBRAL ARTERY ANEURYSMS

OBJECTIVE

The aim of this study was to assess the long-term excess mortality after the rupture of distal anterior cerebral artery (DACA) aneurysms compared with that of a matched general Finnish population in an unselected, population-based series.

METHODS

We identified 280 consecutive patients (119 men, 161 women) treated for ruptured DACA aneurysms (clipped, 262; coiled, 10; no intervention, 8) at two neurosurgical centers serving solely the southern and eastern parts of Finland from 1976 to 2003. All patients were followed from subarachnoid hemorrhage until death or the end of 2004. No patients were lost to follow-up. Long-term excess mortality was estimated using the annual relative survival ratio compared with the general Finnish population matched by age, sex, and calendar time.

RESULTS

The median follow-up period was 9.6 years (range, 0.1-29 yr). The 3-year cumulative relative survival ratio was 0.84 (95% confidence interval, 0.78-0.88), implying 16% excess mortality in the patient group during the first 3 years after subarachnoid hemorrhage. The annual relative survival ratio attained 1.0 at the fourth year of follow-up, indicating no excess mortality thereafter. There were four episodes of recurrent subarachnoid hemorrhage and only one from a treated DACA aneurysm, with a 10-year cumulative risk of 1.4% (95% confidence interval, 0.0-3.0). Cardiovascular disease and cancer were the leading causes of death after 10 years of follow-up.

CONCLUSION

After surviving 3 years after the rupture of a DACA aneurysm, the patients' long-term survival became similar to that of the matched general population. Rebleeding of treated DACA aneurysm was rare.

Complement activation associates with saccular cerebral artery aneurysm wall degeneration and rupture

OBJECTIVE

Saccular cerebral artery aneurysm (SCAA) wall degeneration and inflammatory cell infiltrations associate with aneurysm rupture and subarachnoid hemorrhage, resulting in a devastating form of stroke. The complement system is the key mediator of inflammation and household processing of injured tissue. We studied how complement activation associates with SCAA wall degeneration and rupture to better understand the pathobiology of SCAA wall rupture.

METHODS

Unruptured (n = 26) and ruptured (n = 32) SCAA fundi resected after microsurgical clipping were studied by immunostaining for complement activation (membrane attack complex [MAC]) and by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling reaction for related cell death. Complement activation was correlated with clinical and other histological parameters. Electromicroscopy and immunoelectron microscopy were used for locating MAC depositions at the ultrastructural level.

RESULTS

MAC localized consistently in a decellularized layer in the outer SCAA wall, and was found in all SCAA samples. The percentage of MAC-positive area relative to the total SCAA wall surface area (range, 5-77%) was greater in ruptured (n = 25; median, 39%) than in unruptured SCAAs (n = 18; median, 20%; P = 0.005). It also associated significantly with SCAA wall degeneration (P < 0.001), de-endothelialization(P < 0.001), and CD163+ macrophage (P = 0.023) and T-lymphocyte (P = 0.030) infiltrations. Apoptotic terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling-positive nuclei and MAC were located at the same wall areas in four out of 14 double-stained samples, but no double-positive cells were found. Electromicroscopy and immunoelectron microscopy of an unruptured SCAA showed cell death in the MAC-positive layers in the outer SCAA wall.

CONCLUSION

These data suggests that complement activation and MAC formation are involved in SCAA wall degeneration and rupture.

Association of fatal aneurysmal subarachnoid hemorrhage with human leukocyte antigens in the Finnish population

Human leukocyte antigens (HLA) have been reported to associate with the risk of aneurysmal subarachnoid hemorrhage (SAH) and poor outcome after SAH. Our aim was to identify HLA antigens that associate with the risk of fatal SAH in the Finnish population. Medical records of 600 cadaveric organ donors were reviewed to find organ donors that succumbed to SAH (n = 232) or brain trauma (n = 151). HLA antigen frequencies in these groups were compared with HLA frequencies in a reference population of 10,000 bone marrow donors. Chi-Square test with Bonferroni correction and multiplicative logistic regression models were used and false positive result probabilities (FPRP) were calculated. Alpha-level was 0.01. HLA-A3 associated with fatal SAH (p = 0.0014, OR 1.3 and 95%CI 1.1-1.6) and HLA-DR7 inversely associated with fatal SAH (p = 0.0040, OR 0.3 and 95%CI 0.2-0.6). HLA-A3 but not HLA-DR7 showed also a positive trend in donors with brain trauma. FPRP was below 0.5 for HLA-A3, but clearly above 0.5 for HLA-DR7. HLA-A3 seems to associate with fatal SAH in the Finnish population. Further studies are needed to reveal the pathobiologic mechanisms for how HLA-A3 associates with the risk of fatal SAH in Finns.

Magnetoencephalography in Neurosurgery

OBJECTIVE:

To present applications of magnetoencephalography (MEG) in studies of neurosurgical patients.

METHODS:

MEG maps magnetic fields generated by electric currents in the brain, and allows the localization of brain areas producing evoked sensory responses and spontaneous electromagnetic activity. The identified sources can be integrated with other imaging modalities, e.g., with magnetic resonance imaging scans of individual patients with brain tumors or intractable epilepsy, or with other types of brain imaging data.

RESULTS:

MEG measurements using modern whole-scalp instruments assist in tailoring individual therapies for neurosurgical patients by producing maps of functionally irretrievable cortical areas and by identifying cortical sources of interictal and ictal epileptiform activity. The excellent time resolution of MEG enables tracking of complex spaciotemporal source patterns, helping, for example, with the separation of the epileptic pacemaker from propagated activity. The combination of noninvasive mapping of subcortical pathways by magnetic resonance imaging diffusion tensor imaging with MEG source localization will, in the near future, provide even more accurate navigational tools for preoperative planning. Other possible future applications of MEG include the noninvasive estimation of language lateralization and the follow-up of brain plasticity elicited by central or peripheral neural lesions or during the treatment of chronic pain.

CONCLUSION:

MEG is a mature technique suitable for producing preoperative “road maps” of eloquent cortical areas and for localizing epileptiform activity.

Growth factor receptor expression and remodeling of saccular cerebral artery aneurysm walls: implications for biological therapy preventing rupture

OBJECTIVE

Remodeling of the saccular cerebral artery aneurysm (SCAA) wall, known to be associated with rupture, might be modified with bioactive endovascular implants or systemic drug therapy targeted at growth factor receptors to prevent rupture. The receptors regulating SCAA wall remodeling are, however, unknown.

MATERIALS AND METHODS

Immunostaining for 12 growth factor receptors, and markers for matrix synthesis, proliferation, and inflammatory cell infiltration, were analyzed in 21 unruptured and 35 ruptured aneurysm fundi resected after microsurgical clipping of the aneurysm neck. The results were compared with clinical and radiological data.

RESULTS

Eleven of the 12 receptors studied were expressed at varying intensities in the 56 SCAA walls. Only transforming growth factor (TGF)beta-R2 and vascular endothelial growth factor (VEGF)-R1 were associated with rupture and basic fibroblast growth factor-R1 with minor leaks (P = 0.018). TGFbeta-R3 and VEGF-R1 was associated with wall remodeling (P = 0.043 and 0.027), and VEGF-R1 was associated with T-cell and macrophage infiltration as well as organization of luminal thrombosis (P = 0.019). VEGF-R2 was associated with myointimal hyperplasia (P = 0.017) and proliferation (P < 0.001).

CONCLUSION

VEGF, TGFbeta, and basic fibroblast growth factor receptors were associated with SCAA wall remodeling, making them potential targets for bioactive endovascular implants or drug therapy aiming to reinforce the SCAA wall.

Contribution of mural and bone marrow-derived neointimal cells to thrombus organization and wall remodeling in a microsurgical murine saccular aneurysm model

OBJECTIVE

Endovascular occlusive therapy of human saccular cerebral artery aneurysms may fail because of thrombus recanalization and incomplete neointima formation. Bone marrow-derived progenitor cells may contribute to these processes, but their role in human saccular cerebral artery aneurysms and experimental aneurysm models remains unclear.

METHODS

Experimental saccular aneurysms were constructed from syngeneic thoracic aortas transplanted end-to-side to the abdominal aorta of Wistar rats (n = 14), C57/B6 mice (n = 13), ApoE mice (n = 7), reporter gene expressing ROSA mice (n = 7), and mice with labeled bone marrow (ROSA [n = 12] or green fluorescent protein [n = 3]). Magnetic resonance imaging or angiography was used to monitor patency of the experimental aneurysms. Histology and immunohistochemistry were used to study thrombus organization and neointima formation and X-gal staining and confocal microscopy to study the origin of neointimal cells.

RESULTS

Experimental aneurysms developed luminal pads of neointimal hyperplasia or organizing thrombosis that became thicker and occluded partly the lumen at later time points during the first week. Reporter gene mice (ROSA) revealed that 42 to 81% (median, 58%) of neointimal hyperplasia/organizing thrombosis was derived from the experimental aneurysm wall. Bone marrow-derived neointimal cells were found in only 5 of 15 mice (range, 11-73 per section; a median of 22 cells among a total of 2000-6000 wall cells).

CONCLUSION

Thrombus organizing or neointimal cells were mostly derived from the experimental aneurysm wall, with only a minor contribution from the bone marrow. In human saccular cerebral artery aneurysms, the contribution of bone marrow-derived neointimal cells might be more important and should be compared with that found in other experimental models used to develop endovascular therapies.

Uptake of 4-borono-2-[18F]fluoro-L-phenylalanine in sporadic and neurofibromatosis 2-related schwannoma and meningioma studied with PET

PURPOSE

Meningiomas and schwannomas associated with neurofibromatosis 2 (NF2) are difficult to control by microsurgery and stereotactic radiotherapy alone. Boron neutron capture therapy (BNCT) is a chemically targeted form of radiotherapy requiring increased concentration of boron-10 in tumour tissue. PET with the boron carrier 4-borono-2-[(18)F]fluoro-L-phenylalanine ([(18)F]FBPA) allows investigation of whether 4-borono-L-phenylalanine (BPA) concentrates in NF2 tumours, which would make BNCT feasible.

METHODS

We studied dynamic uptake of [(18)F]FBPA in intracranial meningiomas (n=4) and schwannomas (n=6) of five sporadic and five NF2 patients. Tracer input function and cerebral blood volume were measured. [(18)F]FBPA uptake in tumour and brain was assessed with a three-compartmental model and graphical analysis. These, together with standardised uptake values (SUVs), were used to define tumour-to-brain [(18)F]FBPA tissue activity gradients.

RESULTS

Model fits with three parameters K (1) (transport), k (2) (reverse transport) and k (3) (intracellular metabolism) were found to best illustrate [(18)F]FBPA uptake kinetics. Maximum SUV was two- to fourfold higher in tumour as compared with normal brain and independent of NF2 status. The increased uptake was due to higher transport of [(18)F]FBPA in tumour. In multiple-time graphical analysis (MTGA, Gjedde-Patlak plot) the tumour-to-brain [(18)F]FBPA influx constant (K (i) -MTGA) ratios varied between 1.8 and 5.4 in NF2-associated tumours while in sporadic tumours the ratio was 1-1.4.

CONCLUSION

[(18)F]FBPA PET offers a viable means to evaluate BPA uptake in meningiomas and schwannomas in NF2. Based on our results on tumour uptake of [(18)F]FBPA, some of these benign neoplasms may be amenable to BNCT.

Human androgen receptor gene ligand-binding-domain mutations leading to disrupted interaction between the N- and C-terminal domains

Most mutations in the androgen receptor (AR) ligand-binding domain (LBD) disrupt binding of the natural ligands: dihydrotestosterone and testosterone. Some AR LBD mutations do not affect ligand binding but they disrupt androgen-induced interaction of the N-terminal motif FXXLF and C-terminal activation function 2 (AF2). As N-/C-terminal interaction requires binding of agonists that have androgen activity in vivo, it correlates well with the phenotype. To study this further, we searched the Cambridge intersex database for patients with a detected missense mutation in the AR LBD presenting with normal ligand binding. Six mutations (D695N, Y763C, R774H, Q798E, R855H and L907F) were selected and introduced by site-directed mutagenesis into the pSVAR and pM-LBD plasmids. The transactivational potential of the wild-type and mutant androgen receptors (pSVAR) was examined by dual-luciferase assay using pGRE-LUC as a reporter vector. N-/C-terminal interaction was studied by mammalian two-hybrid assay using wild-type and mutated AR LBD (pM-LBD), pVP16-rAR-(5-538) (encoding rat amino-terminal AR) and pCMX-UAS-TK-LUC as a reporter. AR LBD mutations D695N, R774H and L907F presented with minimal transactivational capacity and N-/C-terminal interaction was totally disrupted. Mutations Y763C and R885H had some residual dose-dependent transactivational potential and minimal N-/C-terminal interaction. Q798E presented with good transactivational potential and it showed only mild reduction in N-/C-terminal interaction. With the selected mutations, N-/C-terminal interaction correlated well with AR transactivation and the phenotype. Disrupted N-/C-terminal interaction is capable of providing the mechanism for androgen-insensitivity syndrome in most cases where the mutation in the LBD does not disrupt ligand binding. Furthermore, mutations leading to the disrupted N-/C-terminal interaction can be localized to certain critical regions in the three-dimensional structure of the AR LBD. Our study shows that apart from the previously reported regions, regions just before helix 3, between helices 5 and 6, and at helix 10 are also important for AR N-/C-terminal interaction.

1H MRS studies in the Finnish boron neutron capture therapy project: detection of 10B-carrier, L-p-boronophenylalanine-fructose

This article summarizes the current status of 1H MRS in detecting and quantifying a boron neutron capture therapy (BNCT) boron carrier, L-p-boronophenylalanine-fructose (BPA-F) in vivo in the Finnish BNCT project. The applicability of 1H MRS to detect BPA-F is evaluated and discussed in a typical situation with a blood containing resection cavity within the gross tumour volume (GTV). 1H MRS is not an ideal method to study BPA concentration in GTV with blood in recent resection cavity. For an optimal identification of BPA signals in the in vivo 1H MR spectrum, both pre- and post-infusion 1H MRS should be performed. The post-infusion spectroscopy studies should be scheduled either prior to or, less optimally, immediately after the BNCT. The pre-BNCT MRS is necessary in order to utilise the MRS results in the actual dose planning.

Water dissection technique of Toth for opening neurosurgical cleavage planes

BACKGROUND

The low-pressure water dissection technique of Toth, first reported in 1987, is a method to cautiously open neurosurgical cleavage planes such as the sylvian fissure or the interhemispheric space, and the interfaces between extraparenchymal masses and the adjacent brain. The aim of this technical report is to present our long-term experience with this simple and elegant asset of microneurosurgery and to promote its widespread use.

METHOD

Water is injected under microscopic control by a hand-held syringe with a blunt needle or by an irrigating balloon applying repeated injections of physiological saline into the cleavage plane to open it.

FINDINGS AND CONCLUSION

The water dissection technique of Toth has been extensively used in Budapest and Helsinki in thousands of microsurgical cases, in removal of meningiomas and to open sylvian and interhemispheric fissure. In our experience, there have been no noticeable complications, and we recommend this technique for widespread use. It is a very inexpensive, simple, and effective method not requiring any expensive or complicated devices.

Ezrin expression in tissue microarray of primary and recurrent gliomas

Malignant progression, infiltrative growth pattern and recurrencies after surgery are characteristic features of diffuse gliomas. Ezrin is a membrane-cytoskeleton linker protein expressed in several types of neoplasms. In experimental models, increased ezrin expression correlates with invasion of malignant glioma cells. We studied ezrin expression and its correlation with patient survival in 229 primary and recurrent astrocytomas (WHO grades II-IV), oligodendrogliomas (II-III) and oligoastrocytomas (II-III) of 113 patients. Ezrin expression as evaluated by immunohistochemistry and immunoblotting was detected in all studied glioma types. Staining intensity and number of immunoreactive cells correlated with increasing malignancy of astrocytomas and oligoastrocytomas (P = 0.001). Ezrin expression was strongest in astrocytomas (P = 0.006). Also oligodendrogliomas were positive for ezrin. High ezrin expression in primary gliomas correlated with shorter time to recurrence (P < 0.05) and poor overall survival (P < 0.05) of the patients. Ezrin expression increased during progression of the tumours (P < 0.05). However, ezrin was not an independent prognostic factor. The results of this study show that ezrin expression is associated with progression of gliomas and correlates with histological cell type and WHO tumour grade.

Remodeling of Saccular Cerebral Artery Aneurysm Wall Is Associated With Rupture

Background and Purpose— The cellular mechanisms of degeneration and repair preceding rupture of the saccular cerebral artery aneurysm wall need to be elucidated for rational design of growth factor or drug-releasing endovascular devices.

Methods— Patient records, preoperative vascular imaging studies, and the snap-frozen fundi resected after microsurgical clipping from 66 aneurysms were studied. Immunostainings for markers of smooth muscle cell (SMC) phenotype, proliferation, and inflammatory cell subtypes and TUNEL reaction were performed.

Results— Unruptured (24) and ruptured (42) aneurysms had similar dimensions (median diameter in unruptured 6 mm; median in ruptured 7 mm; P =0.308). We identified 4 basic types of aneurysm wall that associated with rupture: (1) endothelialized wall with linearly organized SMCs (17/66; 42% ruptured), (2) thickened wall with disorganized SMCs (20/66; 55% ruptured), (3) hypocellular wall with either myointimal hyperplasia or organizing luminal thrombosis (14/66; 64% ruptured), and (4) an extremely thin thrombosis-lined hypocellular wall (15/66; 100% ruptured). Apoptosis, de-endothelialization, luminal thrombosis, SMC proliferation, and T-cell and macrophage infiltration associated with rupture. Furthermore, macrophage infiltration associated with SMC proliferation, and both were increased in ruptured aneurysms resected <12 hours from rupture, suggesting that these were not just reactive changes.

Conclusions— Before rupture, the wall of saccular cerebral artery aneurysm undergoes morphological changes associated with remodeling of the aneurysm wall. Some of these changes, like SMC proliferation and macrophage infiltration, likely reflect ongoing repair attempts that could be enhanced with pharmacological therapy.

Undifferentiated sinonasal carcinoma may respond to single-fraction boron neutron capture therapy

A large, rapidly progressing, unresectable undifferentiated sinonasal head and neck carcinoma regressed rapidly following single fraction boron neutron capture therapy (BNCT). The main toxicity consisted of mucositis lasting for a few days. The quality of life improved and was excellent until tumour recurrence 6 months after the date of BNCT.

Intracranial aneurysms in Finnish families: confirmation of linkage and refinement of the interval to chromosome 19q13.3

We recently reported a two-stage genomewide screen of 48 sib pairs affected with intracranial aneurysms (IAs) that revealed suggestive linkage to chromosome 19q13, with a LOD score of 2.58. The region supporting linkage spanned approximately 22 cM. Here, we report a follow-up study of the locus at 19q13, with a sample size expanded to 139 affected sib pairs, along with 83 other affected relative pairs (222 affected relative pairs in total). Suggestive linkage was observed in both independent sample sets, and linkage was significant in the combined set at 70 cM (LOD score 3.50; P=.00006) and at 80 cM (LOD score 3.93; P=.00002). Linkage was highly significant at 70 cM (LOD score 5.70; P=.000001) and at 80 cM (LOD score 3.99; P=.00005) when a covariate measuring the number of affected individuals in the nuclear family was included. To evaluate further the contribution to the linkage signal from families with more than two affected relatives, we performed model-based linkage analysis with a recessive model and a range of penetrances, and we obtained maximum linkage at 70 cM (LOD score 3.16; P=.00007) with a penetrance of 0.3. We then estimated location by using GENEFINDER. The most likely location for a gene predisposing to IAs in the Finnish population is in a region with a 95% confidence interval of 11.6 cM (P=.00007) centered 2.0 cM proximal to D19S246.

Non-invasive transcranial high intensity focused ultrasound (HIFUS) under MRI thermometry and guidance in the treatment of brain lesions

Non-invasive transcranial high intensity focused ultrasound (HIFUS) therapy given under MRI thermometry and image guidance to awake patients lying within the bore of a 1.5 T MRI scanner (a) to thermally ablate brain lesions such as metastases, (b) to cause precise ablative brain lesions in functional disorders, or (c) to locally open the blood-brain-barrier for targeted therapeutic construct delivery--without the radiation risks of stereotactic radiotherapy--may sound science fiction. Kullervo Hynynen, a Finnish-born ultrasound and MRI physicist, and Ferenc Jolesz, a Hungarian-born neurosurgeon and visionary of image guided surgery, have joined forces at Radiology, Brigham & Women's Hospital, Boston, and they have taken every step to realize the vision above, in highly successful collaboration with the industry (GE, InSightec, TxSonics). The sophisticated transcranial HIFUS instrumentation, supported by profound research data from experimental animals and by the clinical experience from extracranial HIFUS targets (breast fibroadenoma, uterine fibroid), is now coming to a phase I clinical trial in cerebral metastases. It remains to be seen whether transcranial HIFUS will find applications in diffuse gliomas such as (a) thermal ablation of selected areas of glioma tissue, (b) opening the blood-brain-barrier for therapeutic constructs to enter selected areas, or (c) activating such constructs in desired areas. The prophecy of Dr. Jolesz, "this technology will put neurosurgeons out of business", may not fulfill during our lifetime.

Plasminogen activation in neurofibromatosis 2-associated and sporadic schwannomas

BACKGROUND

Schwannomas are usually benign tumours which occur sporadically or in association with neurofibromatosis 2 (NF2), an autosomal dominant disorder. Invasiveness and higher proliferative potential compared to sporadic tumours are features of NF2-associated schwannomas.

METHOD

We studied urokinase (uPA), tissue-type plasminogen activator (tPA), urokinase receptor (uPAR) and plasminogen activator inhibitor-1 (PAI-1) expression by in situ hybridization and by immunohistochemistry in 14 NF2 and 15 sporadic patients with 34 schwannomas. uPAR and vitronectin immunohistochemistry were also studied. Three sural nerve specimens were included as Schwann cell controls.

FINDINGS

Both schwannoma groups expressed prominent levels of uPA and tPA. Semiquantitative analysis of the in situ hybridization and immunoreactivity demonstrated that NF2 schwannomas expressed less PAI-1 at the mRNA level than sporadic schwannomas (score 1.63+/-0.41 vs. 2.05+/-0.75) and less total PAI-1 at the antigen level (score 1.55+/-0.66 vs. 2.07+/-0.56). PAI-1 was mostly in a free form in NF2 schwannomas compared to the sporadic counterparts (score 1.85+/-0.73 vs. 1.46+/-0.58), whereas there was less uPAR antigen in NF2 schwannomas than in the sporadic counterparts (score 1.18+/-0.49 vs. 1.68+/-0.56). Sural nerve Schwann cells did not express detectable level of PAI-1 and at the most a minor amount of tPA.

CONCLUSIONS

Schwann cells of tumour cell origin, both in sporadic and NF2 schwannomas, expressed elevated levels of plasminogen activators and PAI-1 compared to normal suralic nerve Schwann cells. Furthermore, there seemed to be an imbalance in the PA-PAI-1 system in NF2-associated schwannomas. Although our methods are more descriptive than quantitative, we suggest that the somewhat more aggressive behavior of NF2-associated schwannomas compared to sporadic schwannomas may be based on the local proteolytic activity.

Familial intracranial aneurysms: an analysis of 346 multiplex Finnish families

BACKGROUND AND PURPOSE

Genetic risk factors are considered important in the development, growth, and rupture of intracranial aneurysms; however, few have been identified. We analyzed intracranial aneurysm families with at least 2 affected persons and determined relationships between affected persons and assessed the inheritance patterns of aneurysms.

METHODS

Families with > or =2 members with verified diagnoses of intracranial aneurysms were recruited from Kuopio and Helsinki, Finland. Families with a diagnosis of other heritable disorders that have associated intracranial aneurysms, such as autosomal dominant polycystic kidney disease, were excluded.

RESULTS

We identified 346 Finnish multiplex families with 160 (46.2%) male and 186 (53.8%) female index cases. There were a total of 937 aneurysm cases, with an average of 2.7 cases per family. The majority of the families had only 2 affected relatives (n=206; 59.5%), although there were families with up to 6 (n=10), 7 (n=1), 8 (n=1), or 10 (n=2) affected persons. The affected relatives of the index cases included 108 sisters, 116 brothers, 105 parents, 30 children, 15 grandparents, 102 aunts or uncles, and 64 cousins. Of the 937 affected persons, 569 (60.7%) were alive and available for genetic analysis. Inheritance patterns consistent with autosomal recessiveness were observed in 198 (57.2%), autosomal dominance in 126 (36.4%), and autosomal dominance with incomplete penetrance in 19 (5.5%) of the families.

CONCLUSIONS

The collection is the most extensive published to date and extends previous observations of familial aggregation that are consistent with a major gene effect.

A phase 3 trial of local chemotherapy with biodegradable carmustine (BCNU) wafers (Gliadel wafers) in patients with primary malignant glioma

A previous placebo-controlled trial has shown that biodegradable 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) wafers (Gliadel wafers) prolong survival in patients with recurrent glioblastoma multiforme. A previously completed phase 3 trial, also placebo controlled, in 32 patients with newly diagnosed malignant glioma also demonstrated a survival benefit in those patients treated with BCNU wafers. Because of the small number of patients in that trial, a larger phase 3 trial was performed to confirm these results. Two hundred forty patients were randomized to receive either BCNU or placebo wafers at the time of primary surgical resection; both groups were treated with external beam radiation postoperatively. The two groups were similar for age, sex, Karnofsky performance status (KPS), and tumor histology. Median survival in the intent-to-treat group was 13.9 months for the BCNU wafer-treated group and 11.6 months for the placebo-treated group (log-rank P -value stratified by country = 0.03), with a 29% reduction in the risk of death in the treatment group. When adjusted for factors affecting survival, the treatment effect remained positive with a risk reduction of 28% ( P = 0.03). Time to decline in KPS and in 10/11 neuroperformance measures was statistically significantly prolonged in the BCNU wafer-treated group ( P </= 0.05). Adverse events were comparable for the 2 groups, except for CSF leak (5% in the BCNU wafer-treated group vs. 0.8% in the placebo-treated group) and intracranial hypertension (9.1% in the BCNU wafer-treated group vs. 1.7% in the placebo group). This study confirms that local chemotherapy with BCNU wafers is well tolerated and offers a survival benefit to patients with newly diagnosed malignant glioma.

A phase 3 trial of local chemotherapy with biodegradable carmustine (BCNU) wafers (Gliadel wafers) in patients with primary malignant glioma

A previous placebo-controlled trial has shown that biodegradable 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) wafers (Gliadel wafers) prolong survival in patients with recurrent glioblastoma multiforme. A previously completed phase 3 trial, also placebo controlled, in 32 patients with newly diagnosed malignant glioma also demonstrated a survival benefit in those patients treated with BCNU wafers. Because of the small number of patients in that trial, a larger phase 3 trial was performed to confirm these results. Two hundred forty patients were randomized to receive either BCNU or placebo wafers at the time of primary surgical resection; both groups were treated with external beam radiation postoperatively. The two groups were similar for age, sex, Karnofsky performance status (KPS), and tumor histology. Median survival in the intent-to-treat group was 13.9 months for the BCNU wafer-treated group and 11.6 months for the placebo-treated group (log-rank P -value stratified by country = 0.03), with a 29% reduction in the risk of death in the treatment group. When adjusted for factors affecting survival, the treatment effect remained positive with a risk reduction of 28% ( P = 0.03). Time to decline in KPS and in 10/11 neuroperformance measures was statistically significantly prolonged in the BCNU wafer-treated group ( P </= 0.05). Adverse events were comparable for the 2 groups, except for CSF leak (5% in the BCNU wafer-treated group vs. 0.8% in the placebo-treated group) and intracranial hypertension (9.1% in the BCNU wafer-treated group vs. 1.7% in the placebo group). This study confirms that local chemotherapy with BCNU wafers is well tolerated and offers a survival benefit to patients with newly diagnosed malignant glioma.

Boron neutron capture therapy of brain tumors: clinical trials at the finnish facility using boronophenylalanine

Two clinical trials are currently running at the Finnish dedicated boron neutron capture therapy (BNCT) facility. Between May 1999 and December 2001, 18 patients with supratentorial glioblastoma were treated with boronophenylalanine (BPA)-based BNCT within a context of a prospective clinical trial (protocol P-01). All patients underwent prior surgery, but none had received conventional radiotherapy or cancer chemotherapy before BNCT. BPA-fructose was given as 2-h infusion at BPA-dosages ranging from 290 to 400 mg/kg prior to neutron beam irradiation, which was given as a single fraction from two fields. The average planning target volume dose ranged from 30 to 61 Gy (W), and the average normal brain dose from 3 to 6 Gy (W). The treatment was generally well tolerated, and none of the patients have died during the first months following BNCT. The estimated 1-year overall survival is 61%. In another trial (protocol P-03), three patients with recurring or progressing glioblastoma following surgery and conventional cranial radiotherapy to 50-60 Gy, were treated with BPA-based BNCT using the BPA dosage of 290 mg/kg. The average planning target dose in these patients was 25-29 Gy (W), and the average whole brain dose 2-3 Gy (W). All three patients tolerated brain reirradiation with BNCT, and none died during the first three months following BNCT. We conclude that BPA-based BNCT has been relatively well tolerated both in previously irradiated and unirradiated glioblastoma patients. Efficacy comparisons with conventional photon radiation are difficult due to patient selection and confounding factors such as other treatments given, but the results support continuation of clinical research on BPA-based BNCT.

Clinical implementation of 4-dihydroxyborylphenylalanine synthesised by an asymmetric pathway

Boron neutron capture therapy (BNCT) is an experimental therapeutic modality combining a boron pharmaceutical with neutron irradiation. 4-Dihydroxyborylphenylalanine (L-BPA) synthesised via the asymmetric pathway by Malan and Morin [Synlett. 167-168 (1996)] was developed to be the boron containing pharmaceutical in the first series of Finnish BNCT clinical trials. The final product was >98.5% chemically pure L-BPA with L-phenylalanine and L-tyrosine as the residual impurities. The solubility of L-BPA was enhanced by complex formation with fructose (BPA-F). The pH and osmolarity of the BPA-F preparation is in the physiological range. Careful attention was given to the pharmaceutical quality of the BPA-F preparations. Prior to starting clinical trials the acute toxicity of L-BPA was studied in male albino Sprague-Dawley rats. In accordance with earlier studies no adverse effects were observed. After completion of the development work L-BPA solution was administered to brain tumour patients in conjunction with clinical studies for development and testing of BPA-based BNCT. No clinically significant adverse events attributable to the L-BPA i.v. infusions were observed. We conclude that our synthesis development, complementary preclinical and clinical observations justify the safe use of L-BPA up to clinical phase III studies with L-BPA produced by the asymmetric pathway, originally presented by Malan and Morin in 1996.

Awake craniotomy in glioma surgery

Awake craniotomy is the cheapest and most reliable method to ensure neurological integrity in cerebral gliomas that infiltrate or come close to the eloquent areas of the brain, allowing (a) the localization of eloquent cortical areas by electrical stimulation and epileptic foci by cortical recording, and (b) the monitoring of the functional integrity of awake patients while aiming at subtotal removal of the gliomatous tissue. In addition, awake craniotomy opens a brief but unique window to the living brain for (a) basic neuroscience, including verification of preoperative functional imaging data and recording of electrophysiological correlates of mental processes, and for (b) applied research, including development of innovative instrumentation for brain recording and monitoring as well as screening for potential areas to be modulated in movement disorders and chronic pain.

Debulking or biopsy of malignant glioma in elderly people - a randomised study

BACKGROUND

Patients with radiologically (MRI and/or CT images) suspected malignant glioma is referred to radiotherapy after craniotomy and resection of the tumour or after diagnostic biopsy. Patients with poor preoperative status and elderly patients are diagnosed more often by biopsy and treated by radiotherapy rather than by craniotomy and tumour resection. However, based on previous retrospective studies it is not possible to conclude which procedure is better for elderly patients. Thus a prospective study comparing these two procedures with elderly patients was planned.

METHODS

30 patients older than 65 years with radiologically (CT and/or MRI) obvious malignant glioma were randomised into two groups: I) stereotactic biopsy and II) open craniotomy and resection of the tumour. Nineteen patients were diagnosed to have grade IV glioma and four patients grade III glioma. Seven out of 30 (23%) were followed in the "intention-to-treat" group with diagnosis of stroke (n=3), metastasis (n=2), malignant lymphoma (n=1) and one with out histological diagnosis. Patients with histologically verified malignant glioma (grade III-IV) were diagnosed by stereotactic biopsy (n=13) or by open craniotomy and resection (n=10) and all the patients were referred to radiotherapy. Survival and time of deterioration were followed.

FINDINGS

The overall median survival time was 146 (95% CI 89-175) days after the procedure. The estimated median survival time was 171 (95% CI 146-278) days after the craniotomy versus 85 (95% CI 55-157) days after the biopsy (p=0.035). The estimated survival time was 2.757 times longer (95% CI 1.004-7.568, p=0.049) after craniotomy. However, there was no significant difference in the time of deterioration between these two treatments (p=0.057). Amount of radiotherapy given had a significant effect on survival (p=0.001).

INTERPRETATION

Longer survival time is achieved after open craniotomy and resection of tumour. However, overall benefit of open surgery to patient seems to be modest, while time of deterioration did not differ between two treatment groups. Our results support previous studies on the benefit of radiotherapy in the treatment of malignant glioma.

Acute insulin response tests for the differential diagnosis of congenital hyperinsulinism

Mutations in genes encoding the two subunits of the beta-cell ATP-sensitive potassium channel (K(ATP)) channel (SUR1 and Kir6.2) are the major cause of congenital hyperinsulinism (CHI). In this study, the K(ATP) channel genes were screened in a population-based study that included all verified Finnish CHI patients (n = 43) in a 27-yr period. Seven different mutations were identified, which accounted for 60% of all cases. The functional consequences of the major missense mutations were studied in vivo by determining acute (1-3 min) plasma insulin and C-peptide responses to calcium (n = 18), glucose (n = 12), and tolbutamide (n = 11) in those CHI patients who were able to take part in these studies. C-peptide and insulin responses to calcium were significantly higher in the patients with SUR1-E1506K mutation, compared with patients without K(ATP) channel mutations. The patients with SUR1-V187D mutation showed a reduced response to tolbutamide but unexpectedly did not show any response to calcium stimulation. A compound heterozygous patient with Kir6.2-(-54)/K67N mutations responded to calcium but also to tolbutamide. In conclusion, our results show that a positive response in the calcium test is indicative of a K(ATP) channel mutation, but all mutations cannot be identified with this method. The insulin response to tolbutamide in patients with SUR1 mutations is impaired to different extents, depending on the genotype. The combination of calcium and tolbutamide tests is a useful tool for the detection of CHI patients with K(ATP) channel dysfunction. Our results, however, also demonstrate the complexity of these responses and the difficulties in their interpretation.

Sexual function and fertility in adult females and males with congenital adrenal hyperplasia

Female patients with classic 21-hydroxylase deficiency (21-OHD) present with decreased fertility and low childbirth rates, women with a salt-wasting form of 21-OHD being most severely affected. In cases of undersubstitution with glucocorticoids, tonic androgen secretion disturbs ovulation. However, even adequately substituted females may present with apparent infertility. Despite adrenal androgen suppression, adrenal progesterone secretion can prevent thickening of the endometrium in the follicular phase. Furthermore, functional ovarian hyperandrogenism is a common finding even in women with well-controlled classic 21-OHD. Psychosexual factors may also contribute significantly to decreased childbirth rates found in these patients. Genital ambiguity may lead to a disturbed body image and the patients have been found to feel less feminine than healthy control women. The repeated psychological insult caused by frequent genital examinations and operations is also important, though its exact impact has been difficult to determine. Finally, prenatal androgen excess can cause masculinization of the central nervous system leading to boyish behavior in childhood and decreased heterosexual activity in adulthood. Some recent reports show a high rate of infertility also in men with 21-OHD. They are at risk of benign testicular tumors, adrenal rests, which can lead to permanent infertility. Also, raised adrenal androgen production leading to increased estrogen concentrations can suppress gonadotropin secretion and may lead to a hypogonadotropic state.

Recurrent DNA sequence copy losses on chromosomal arm 6q in capillary hemangioblastoma

Capillary hemangioblastomas (CHB) of the central nervous system, the most common tumor in von Hippel-Lindau (VHL) disease, usually show mutations in the VHL tumor suppressor gene on chromosome 3p25-p26. Because little is known concerning the cytogenetic changes in these tumors, we studied 22 cases through comparative genomic hybridization to screen for DNA copy number changes in both sporadic and VHL-associated CHB. Our analysis revealed that 6 of 22 samples (27%) contained DNA copy number losses, whereas no gains were observed. The most recurrent finding was loss of chromosomal arm 6q, seen in five cases. In two of these cases also loss of chromosome 3 was noted. The third aberration observed was loss of chromosome 8, seen in one case. No differences were noted between VHL-associated and sporadic tumors, nor did the cytogenetic aberrations correlate with the clinical outcome. The loss of 6q, seen in this study and previously in other VHL-associated tumors (renal cell carcinomas and pheochromocytomas) and other tumors, suggest that this chromosome area may contain tumor suppressor genes involved in the early steps of tumorigenesis.

Post-prandial insulin lispro vs. human regular insulin in prepubertal children with Type 1 diabetes mellitus

AIMS

To study whether post-prandial insulin lispro (PL) could be used as a part of insulin therapy instead of premeal human regular insulin (HR) in prepubertal children with Type 1 diabetes mellitus (Type 1 DM).

PATIENTS AND METHODS

In this open, randomized cross-over study patients used either PL or HR at breakfast and at dinner. After a 1-month screening period, patients were randomized to treatment with PL or HR for 3 months and then they crossed over to the other insulin for an additional 3 months. The patients were 24 prepubertal children with Type 1 DM (median age 6.2 years, duration of diabetes 37 months). Home monitoring of 1-day glucose profiles at meals (premeal, 1 h and 2 h after breakfast and after dinner) and HbA1c were measured before randomization, before cross-over, and at the last visit. Data on hypoglycaemic episodes were collected at each of the seven visits. The variables were compared between the two treatments.

RESULTS

Of the patients 22/24 completed the study. There were no major differences in the glucose excursions between PL and HR after breakfast (mean +/- SD: 1-h PL 3.7 +/- 4.7 vs. HR 2.9 +/- 3.9 mmol/l, P = 0.3; 2-h -0.9 +/- 5.4 vs. 0.3 +/- 4.5 mmol/l, P = 0.2, respectively) or after dinner (1-h PL -2.5 +/- 4.8 vs. HR -0.4 +/- 3.7 mmol/l, P = 0.07, 2-h -4.1 +/- 5.2 vs. -0.7 +/- 5.0 mmol/l, P = 0.05, respectively). Mean change of HbA1c was similar in both treatment groups (PL 0.2 +/- 0.8% vs. HR -0.4 +/- 0.7%, P = 0.1). The frequency of hypoglycaemic episodes was 4.9 per patient per month during treatment with PL, and 4.4 during HR (P = 0.3).

CONCLUSION

Treatment with post-prandial lispro as a meal insulin is as effective and safe as traditional treatment with regular insulin in young children.

Adverse long-term effects of brain radiotherapy in adult low-grade glioma patients

OBJECTIVE

To study the long-term effects of radiotherapy on cognitive function in adult patients operated on for low-grade glioma.

METHODS

A cohort of 160 patients who underwent surgery for low-grade gliomas of cerebral hemisphere between 1980 and 1992 in a single institution serving a defined population was studied. At a mean follow-up time of 7 years, 28 of the 101 patients who had postoperative irradiation (and no second surgery or chemotherapy) were still alive and eligible for MRI and neuropsychological study. Twenty-three of 59 patients who did not have radiotherapy, second surgery, or chemotherapy were alive and eligible at a mean of 10 years.

RESULTS

The group that had postoperative irradiation performed significantly worse than the group that did not in cognitive tests. This difference was not accounted for by histologic diagnosis; location, extent of removal, or progression of the tumor; or any patient factor. Leukoencephalopathy was more severe in the group that had postoperative irradiation than in the group without radiotherapy, and correlated to poor memory performances only in the postoperative radiotherapy group. Average Karnofsky performance scale score was significantly lower in the group that had postoperative irradiation than in the group that did not.

CONCLUSION

In adults with low-grade glioma, postoperative radiotherapy poses a significant risk of long-term leukoencephalopathy and cognitive impairment.