[Does youth mean vigorous and age, feeble biological repair mechanisms?]

All living creatures are subject to aging, but our understanding of what governs aging is limited. In the course of a lifetime, with the constant renewal of the organic substance of living creatures errors arise, e.g. in the formation, disposal, and reproduction of DNA, proteins and lipids or in the constant substitution of aging cells in the organs. These errors are recognized and generally counterbalanced by appropriate repair mechanisms. This process is obviously determined partly by environmental influences (e.g. UV radiation, oxidizing influences, thermal shock) and genetic factors (such as the significance of so-called survival genes and gene mutations). In this paper the authors both explain and test the hypothesis that the aging of organs and organisms is the consequence of and not the reason for a progressive weakening of the repair mechanisms throughout life.

CD95 ligand: lethal weapon against malignant glioma?

CD95 (Fas/APO-1) and its ligand (CD95L) belong to a growing cytokine and cytokine receptor family that includes nerve growth factor (NGF) and tumor necrosis factor (TNF) and their corresponding receptors. CD95 expression increases during malignant progression from low-grade to anaplastic astrocytoma and is most prominent in perinecrotic areas of glioblastoma. There is, however, no evidence that CD95 expression in malignant gliomas is triggered by hypoxia or ischemia. Agonistic antibodies to CD95, or the natural ligand, CD95L, induce apoptosis in human malignant glioma cells in vitro. Glioma cell sensitivity to CD95-mediated apoptosis is regulated by CD95 expression at the cell surface and by the levels of intracellular apoptosis-regulatory proteins, including bcl-2 family members. Several cytotoxic drugs synergize with CD95L to kill glioma cells. For as yet unknown reasons, glioma cells may co-express CD95 and CD95L in vitro without undergoing suicide or fratricide. Yet, they kill T cells via CD95/CD95L interactions and are sensitive to exogenously added CD95L. Since CD95L is expressed in gliomas in vivo, too, forced induction of CD95 expression might promote therapeutic apoptosis in these tumors. That glioma cells differ from nontransformed T cells in their sensitivity to CD95 antibodies or recombinant ligand, may allow the development of selective CD95 agonists with high antitumor activity that spare normal brain tissue. A family of death ligand/receptor pairs related to CD95L/CD95, including APO2L (TRAIL) and its multiple receptors is beginning to emerge. Although several issues regarding glioma cell sensitivity to CD95L/CD95-mediated apoptosis await elucidation, CD95 is a promising target for the treatment of malignant glioma.

Bag-1 and Bcl-2 gene transfer in malignant glioma: modulation of cell cycle regulation and apoptosis

Bag-1 is a heat shock 70 kDa (Hsp70)-binding protein that can collaborate with Bcl-2 in suppressing apoptosis under some conditions. Here, we report that 11 of 12 human glioma cell lines express Bag-1 protein in vitro. Moreover, 15 of 19 human glioblastomas expressed Bag-1 as assessed by immunohistochemistry in primary tumor specimens. To examine the biological effects of Bag-1 in glioma cells, we expressed Bag-1 or Bcl-2 transgenes in 2 human malignant glioma cell lines, LN-18 and LN-229. Bag-1 significantly slowed glioma cell growth and reduced clonogenicity of both cell lines in vitro. Coexpressed Bcl-2 abrogated these effects of Bag-1. Intracranial LN-229 glioma xenografts implanted into nude mice revealed a substantial growth advantage afforded by Bcl-2. Bag-1 had no such effect, either in the absence or presence of Bcl-2. Upon serum starvation in vitro, Bcl-2 prevented cell death whereas Bag-1 did not. Both Bcl-2 and Bag-1 slowed proliferation of serum-starved cells when expressed alone. Importantly, coexpression of Bcl-2 and Bag-1 provided a distinct growth advantage under conditions of serum starvation that is probably the result of (i) the death-preventing activity of Bcl-2 and (ii) the property of Bag-1 to overcome a Bcl-2-mediated enhancement of exit from the cell cycle. In contrast to these Bcl-2/Bag-1 interactions observed under serum starvation conditions, Bag-1 did not further enhance the strong protection from staurosporine-, CD95 (Fas/Apo1) ligand-, Apo2 ligand (TRAIL)- or chemotherapeutic drug-induced apoptosis afforded by Bcl-2. Taken together, these results indicate a role for Bag-1/Bcl-2 interactions in providing a survival advantage to cancer cells in a deprived microenvironment that may be characteristic of ischemic/hypoxic tumors such as human glioblastoma multiforme, and suggest that Bcl-2/Bag-1 interactions also modulate cell proliferation.

PCV chemotherapy for recurrent glioblastoma

The authors administered procarbazine, 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU, lomustine), and vincristine (PCV) to 86 patients with recurrent glioblastoma. There were three partial responses, but no complete responses. Median progression-free survival was 17.1 weeks and progression-free survival at 6 months was 38.4%. World Health Organization grade III/IV hematologic toxicity was common (25.6%), but nonhematologic toxicity was mild.

Surviving glioblastoma for more than 5 years: The patient's perspective

The authors performed a comprehensive analysis of the functional outcome of 10 patients who had survived 5 years from a diagnosis of glioblastoma. Neurologic deficits were mild in most patients, but neuropsychological testing demonstrated cognitive deficits in all patients. Depression and anxiety were common. Although most patients thought that their social functioning and work ability were impaired, little reduction in overall quality of life was perceived.

Eosinophilic meningomyelitis in toxocariasis: case report and review of the literature

Toxocariasis is a worldwide-occurring parasitic infection leading to tissue damage in various organs due to wandering Toxocara larvae (visceral larva migrans). More than 40 cases of CNS involvement in children and immunocompetent adults have been documented in detail to date. Here, we present evidence of eosinophilic meningomyelitis in an adult without known risk factors and with positive Toxocara antibody response in CSF, but not in blood. Toxocariasis has to remain among the differential diagnosis in patients with eosinophilic CNS infection even if serological tests in blood are negative. Adult cases seem to be more frequent than previously thought (about 60%).

Adult medulloblastoma: prognostic factors and response to therapy at diagnosis and at relapse

Adult medulloblastoma is a rare tumor with few retrospective studies published so far. The role of adjuvant chemotherapy or chemotherapy at relapse is unclear. This study reports therapy and outcome in all adult (>or=16 years old) medulloblastoma (n=34) and supratentorial primitive neuroectodermal tumor (PNET) patients (n=2) treated in 2 neuro-oncological centers between 1976 and 2002. The median age was 24.5 years (range 16-76). After resection, 16 patients were treated with craniospinal radiotherapy alone, 20 patients also received adjuvant chemotherapy (8 vincristine, CCNU, cisplatin; 7 methotrexate alone or methotrexate/vincristine-based polychemotherapy; 5 other protocols). Median survival in the whole cohort was 126 months (2+ - 200+months). Five-year and 10-year survival rates were 79 % and 56%. Adjuvant chemotherapy was associated with a non-significant trend to prolonged survival (relative risk (RR) 1.89; p=0.068). The median progression-free survival (PFS) after primary therapy was 83 months. At relapse, 10 of 12 evaluable patients achieved a complete response upon second-line therapy. The median survival times from first (n=17) and second relapse (n=9) were 21 months (0-67+ months; 5/17 without second relapse) and 20 months (1-29 months). Cox regression analysis revealed the infiltration of the floor of the 4(th) ventricle at diagnosis as the only therapy-independent prognostic factor (RR 0.48; p=0.03). In conclusion, adjuvant chemotherapy may prolong survival in adult medulloblastoma patients. Moreover, second-line therapy may be beneficial for these patients. As in pediatric medulloblastoma patients, primary infiltration of the floor of the 4(th) ventricle indicates a poor prognosis.

Spinocerebellar ataxia type 5: clinical and molecular genetic features of a German kindred

The authors report a German family with autosomal dominant cerebellar ataxia tightly linked to the spinocerebellar ataxia type 5 (SCA5) locus (multipoint lod score 5.76). The phenotype is characterized by a purely cerebellar syndrome with a downbeat nystagmus occurring prior to the development of other features. Imaging studies demonstrated cortical cerebellar atrophy. Progression is slow even in patients with a disease onset during the second decade. The age at onset varies from 15 to 50 years.

A patient with Marfan's syndrome and neurofibromatosis type 1 with polyneuropathy

Both Marfan's syndrome and neurofibromatosis type 1 are hereditary, autosomal dominant conditions. Here, we report the rare case of a patient fulfilling the clinical criteria for both diseases. In the absence of a family history of either of the two conditions, two independent de novo mutations are the most likely cause.

Vascular endothelial growth factor (VEGF) in leptomeningeal metastasis: diagnostic and prognostic value

This study examined the diagnostic and prognostic value of vascular endothelial growth factor (VEGF) levels in the cerebrospinal fluid (CSF) of 39 patients with leptomeningeal metastasis (LM). Vascular endothelial growth factor levels at diagnosis were significantly higher in patients with LM (median 359 pg ml⁻¹) than in patients with other neurological diseases (median <25 pg ml⁻¹). The specificity of VEGF levels above 250 pg ml⁻¹ for LM was high (98.3%), while the sensitivity was low (51.4%; 73% for VEGF values above 100 pg ml⁻¹). In 49% of the LM patients, particularly with lymphoma or medulloblastoma, VEGF levels were below 250 pg ml⁻¹ and thus in the range of VEGF levels in other neurological diseases. Vascular endothelial growth factor levels correlated significantly with CSF lactate and albumin. Vascular endothelial growth factor levels mirrored the clinical course with a marked reduction in response to therapy and an increase at relapse in some patients who had serial CSF samples available. Multivariate Cox regression analysis showed VEGF below 100 pg ml⁻¹ (relative risk (RR)=4.24, P=0.0002) and age below 60 years (RR=2.5, P=0.004) to be associated with longer survival in LM. In conclusion, CSF VEGF levels in LM vary considerably. High VEGF levels have a very high specifity for LM and may help to establish the diagnosis. The role of VEGF as a predictor of outcome should be substantiated in prospective studies.

One week on/one week off: A novel active regimen of temozolomide for recurrent glioblastoma

Twenty-one patients with recurrent or progressive glioblastoma were enrolled in a prospective phase II trial to determine the safety and efficacy of a 1-week on/1-week off regimen of temozolomide administered at 150 mg/m2 on days 1 to 7 and days 15 to 21 of 28-day treatment cycles. Two patients achieved a partial response (10%), and 17 patients (81%) had stable disease. The median progression-free survival was 5 months. The progression-free survival at 6 months was 48%.