A German multicenter, randomized phase III trial comparing irinotecan-carboplatin with etoposide-carboplatin as first-line therapy for extensive-disease small-cell lung cancer.

BACKGROUND: This trial was designed to prove superiority of irinotecan over etoposide combined with carboplatin in extensive-disease small-cell lung cancer. PATIENTS AND METHODS: Patients were randomly assigned to receive carboplatin area under the curve 5 mg x min/ml either in combination with irinotecan 50 mg/m2 on days 1, 8, and 15 (IP) or etoposide 140 mg/m2 on days 1-3 (EP). Primary end point was progression-free survival (PFS) at 6 months. Secondary end points were overall survival (OS), response rate, and toxicity. RESULTS: Of 226 patients, 216 were eligible. Median PFS was 6.0 months [95% confidence interval (CI) 5.0-7.0] in the IP arm and 6.0 months (95% CI 5.2-6.8) in EP arm (P = 0.07). Median survival was 10.0 months (95% CI 8.4-11.6) and 9.0 months (95% CI 7.6-10.4) in the IP and EP arm (P = 0.06), respectively. Hazard ratios for disease progression and OS were 1.29 (95% CI 0.96-1.73, P = 0.095) and 1.34 (95% CI 0.97-1.85, P = 0.072), respectively. No difference in response rates was observed. Grade 3 and 4 hematologic toxicity favored the IP arm, whereas diarrhea was significantly more frequent in the IP arm. CONCLUSION: This trial failed to show superiority of irinotecan over etoposide in combination with carboplatin.

Laminar-specific and developmental expression of aquaporin-4 in the mouse hippocampus.

Mice deficient in the water channel aquaporin-4 (AQP4) demonstrate increased seizure duration in response to hippocampal stimulation as well as impaired extracellular K+ clearance. However, the expression of AQP4 in the hippocampus is not well described. In this study, we investigated (i) the developmental, laminar and cell-type specificity of AQP4 expression in the hippocampus; (ii) the effect of Kir4.1 deletion on AQP4 expression; and (iii) performed Western blot and RT-PCR analyses. AQP4 immunohistochemistry on coronal sections from wild-type (WT) or Kir4.1-/- mice revealed a developmentally-regulated and laminar-specific pattern, with highest expression in the CA1 stratum lacunosum-moleculare (SLM) and the molecular layer (ML) of the dentate gyrus (DG). AQP4 was colocalized with the glial markers glial fibrillary acidic protein (GFAP) and S100ß in the hippocampus, and was also ubiquitously expressed on astrocytic endfeet around blood vessels. No difference in AQP4 immunoreactivity was observed in Kir4.1-/- mice. Electrophysiological and postrecording RT-PCR analyses of individual cells revealed that AQP4 and Kir4.1 were co-expressed in nearly all CA1 astrocytes. In NG2 cells, AQP4 was also expressed at the transcript level. This study is the first to examine subregional AQP4 expression during development of the hippocampus. The strikingly high expression of AQP4 in the CA1 SLM and DG ML identifies these regions as potential sites of astrocytic K+ and H2O regulation. These results begin to delineate the functional capabilities of hippocampal subregions and cell types for K+ and H2O homeostasis, which is critical to excitability and serves as a potential target for modulation in diverse diseases.

Intrathecal application of neuroectodermally converted stem cells into a mouse model of ALS: limited intraparenchymal migration and survival narrows therapeutic effects.

Stem and progenitor cells provide a promising therapeutic strategy for amyotrophic lateral sclerosis (ALS). To comparatively evaluate the therapeutic potentials of human bone marrow-derived mesodermal stromal cells (hMSCs) and umbilical cord blood cells (hUBCs) in ALS, we transplanted hMSCs and hUBCs and their neuroectodermal derivatives (hMSC-NSCs and hUBC-NSCs) into the ALS mouse model over-expressing the G93A mutant of the human SOD1 gene. We used a standardized protocol similar to clinical studies by performing a power calculation to estimate sample size prior to transplantation, matching the treatment groups for gender and hSOD-G93A gene content, and applying a novel method for directly injecting 100,000 cells into the CSF (the cisterna magna). Ten days after transplantation we found many cells within the subarachnoidal space ranging from frontal basal cisterns back to the cisterna magna, but only a few cells around the spinal cord. hMSCs and hMSC-NSCs were also located within the Purkinje cell layer. Intrathecal cell application did not affect survival times of mice compared to controls. Consistently, time of disease onset and first pareses, death weight, and motor neuron count in lumbar spinal cord did not vary between treatment groups. Interestingly, transplantation of hMSCs led to an increase of pre-symptomatic motor performance compared to controls in female animals. The negative outcome of the present study is most likely due to insufficient cell numbers within the affected brain regions (mainly the spinal cord). Further experiments defining the optimal cell dose, time point and route of application and particularly strategies to improve the homing of transplanted cells towards the CNS region of interest are warranted to define the therapeutic potential of mesodermal stem cells for the treatment of ALS.

Traumatic retropharyngeal pseudomeningocele with atlanto-occipital dislocation in a neurologically intact patient.

Traumatic retropharyngeal pseudomeningoceles occur rarely, are associated with severe trauma, and have been reported in patients with significant neurologic deficits at presentation. We report the rare occurrence of a pseudomeningocele following a high-speed motor vehicle accident. Neurological examination showed the patient to be briskly following commands, with intact cranial nerve, motor, and sensory function. CT/MR imaging showed subarachnoid hemorrhage involving the interpeduncular cistern, a clivus fracture, a right occipital condyle fracture, an atlanto-occipital subluxation, aortic arch transection (stable and contained on CT angiogram), multiple rib fractures on the right side with associated pneumothorax, hemothorax and pulmonary contusions. His cervical spine was stabilized in a halo. He was subsequently managed in the intensive care unit and remained neurologically intact. A repeat MRI showed the interval development of a 2×1.5 cm pseudomeningocele at the craniocervical junction medial to the left occipital condyle communicating with the left anterolateral aspect of the spinal canal. Traumatic pseudomeningoceles are associated with large deceleration forces at the time of injury and are usually associated with significant neurologic deficits at presentation. However, they can arise and give rise to symptoms in a delayed fashion in trauma patients who are neurologically intact at initial presentation.

Docetaxel/gemcitabine or cisplatin/gemcitabine followed by docetaxel in the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC): results of a multicentre randomized phase II trial.

BACKGROUND: Most patients (pts) with metastatic non-small cell lung cancer (NSCLC) receive either single agents or chemotherapy doublets. Recent studies have demonstrated that triple-agent therapies may improve the response rate, but are associated with significant toxicity, and frequently do not prolong survival. A sequential triple-agent schedule may combine acceptable tolerability and good efficacy. We therefore conducted a multicentre, prospectively randomized study that evaluates a sequential three-drug schedule and a platinum-free doublet regimen. PATIENTS AND METHODS: The pts with union international contre le cancer (UICC) stage IV NSCLC were randomized to one of two schedules: in arm Doc-Gem, they received gemcitabine (900 mg/m(2), 30 min infusion) on days 1 and 8, and docetaxel (75 mg/m(2), 1 h infusion) on day 1, repeated every 3 weeks up to six cycles. In arm Cis-Gem-->Doc, gemcitabine (900 mg/m(2), days 1 and 8) and cisplatin (70 mg/m(2), 1 h infusion, day 1) were given for three cycles, followed by three cycles of docetaxel (100 mg/m(2), day 1, repeated every 3 weeks). RESULTS: One hundred and thirteen pts were randomized to arms Doc-Gem (55 pts) and Cis-Gem-->Doc (58 pts). With Doc-Gem, 20.4% of pts responded to the treatment whereas 31.0% responded in arm Cis-Gem-->Doc (overall response, intent-to-treat, difference not significant). The median time to progression was 3.6 months in arm Doc-Gem [95% confidence interval (CI) 1.4, 5.9] and 5.2 months in arm Cis-Gem-->Doc (95% CI 3.1, 7.3). The median survival was 8.7 months with treatment Doc-Gem (95% CI 5.7, 11.6) and 9.4 months with treatment Cis-Gem-->Doc (95% CI 7.8, 11.0). The 1-year survival rates were 34 and 35%, respectively. Mild to moderate leukopenia was frequently seen with both schedules. Other common adverse events (AE) were nausea/vomiting, thrombocytopenia, anaemia, diarrhoea, and infections. No significant differences in AEs were observed between the schedules except for nausea/vomiting, which occurred more frequently with Cis-Gem-->Doc. CONCLUSION: The sequential therapy comprising cisplatin, gemcitabine, and docetaxel demonstrated promising tumour control whereas the platinum-free combination (docetaxel/gemcitabine) was very well tolerated. However, the schedules resulted in comparable survival to recent large trials in pts with advanced NSCLC. The present results do not justify further phase III investigation.

Increased seizure duration in mice lacking aquaporin-4 water channels.

Aquaporins are intrinsic membrane proteins involved in water transport in fluid-transporting tissues. In the brain, aquaporin-4 (AQP4) is expressed widely by glial cells, but its function is unclear. Extensive basic and clinical studies indicate that osmolarity affects seizure susceptibility, and in our previous studies we found that AQP4 -/- mice have an elevated seizure threshold in response to the chemoconvulsant pentylenetetrazol. In this study, we examined the seizure phenotype of AQP4 -/- mice in greater detail using in vivo electroencephalographic recording. AQP4 -/- mice were found to have dramatically longer stimulation-evoked seizures following hippocampal stimulation as well as a higher seizure threshold. These results implicate AQP4 in water and potassium regulation associated with neuronal activity and seizures.

[Brain metastases of lung cancer]. / Hirnmetastasen beim Lungenkarzinom.

Cerebral metastases are a frequent complication of lung cancer. They often determine patients' prognosis and need urgent therapeutic intervention. Based on histologic type, former therapies, age and performance of the patient, the number of cerebral lesions and the extracerebral tumour activity, individualized treatments are applied. For patients who suffer from non-small cell lung cancer and a single CNS lesion the best results can be achieved if they are surgically resected or receive radiosurgery. Their survival time can be markedly increased in comparison to patients who undergo whole brain irradiation. If multiple metastases are seen in CT or MRI, whole brain irradiation is the therapy to choose. Furthermore it should be initiated if small cell lung cancer metastasizes to the brain. More aggressive local treatment options appear promising, but a clear role for them has not yet been defined. Systemic chemotherapy gains more attention in the treatment of small and non-small cell lung cancer with brain metastases. How to increase the efficacy through simultaneous application of chemo- and radiotherapy is tested in current trials. This article gives an overview on clinical presentation and diagnosis of cerebral metastases in lung cancer and reviews current treatment options.

Emerging role of gap junctions in epilepsy.

This review highlights the contribution of gap junctions to the pathophysiology of epilepsy. The tissue expression and spatiotemporal regulation of connexins is discussed, and the phenotypes of specific connexin knockouts are considered. Electrophysiologic studies have implicated gap junctions in the generation of very fast oscillations preceding seizures. Gap junction inhibitors have shown powerful anticonvulsant effects, to date primarily in in vitro studies. Specific inhibition of gap junctions in vivo along with more detailed human tissue studies are needed to understand more fully the role of gap junctions in epileptogenesis.

New insights into water transport and edema in the central nervous system from phenotype analysis of aquaporin-4 null mice.

Aquaporin-4 (AQP4) is the major water channel in the CNS. Its expression at fluid-tissue barriers (blood-brain and brain-cerebrospinal fluid barriers) throughout the brain and spinal cord suggests a role in water transport under normal and pathological conditions. Phenotype studies of transgenic mice lacking AQP4 have provided evidence for a role of AQP4 in cerebral water balance and neural signal transduction. Primary cultures of astrocytes from AQP4-null mice have greatly reduced osmotic water permeability compared with wild-type astrocytes, indicating that AQP4 is the principal water channel in these cells. AQP4-null mice have reduced brain swelling and improved neurological outcome following water intoxication and focal cerebral ischemia, establishing a role of AQP4 in the development of cytotoxic (cellular) cerebral edema. In contrast, brain swelling and clinical outcome are worse in AQP4-null mice in models of vasogenic (fluid leak) edema caused by freeze-injury and brain tumor, probably due to impaired AQP4-dependent brain water clearance. AQP4-null mice also have markedly reduced acoustic brainstem response potentials and significantly increased seizure threshold in response to chemical convulsants, implicating AQP4 in modulation of neural signal transduction. Pharmacological modulation of AQP4 function may thus provide a novel therapeutic strategy for the treatment of stroke, tumor-associated edema, epilepsy, traumatic brain injury, and other disorders of the CNS associated with altered brain water balance.

Molecular mechanisms of brain tumor edema.

Despite their diverse histological types, most brain tumours cause brain oedema, which is a significant cause of patient morbidity and mortality. Brain tumour oedema occurs when plasma-like fluid enters the brain extracellular space through impaired capillary endothelial tight junctions in tumours. Under-expression of the tight junction proteins occludin, claudin-1 and claudin-5 are key molecular abnormalities responsible for the increased permeability of tumour endothelial tight junctions. Recent evidence suggests that the membrane water channel protein aquaporin-4 (AQP4) also plays a role in brain tumour oedema. AQP4-deficient mice show remarkably altered brain water balance after various insults, including brain tumour implantation. AQP4 expression is strongly upregulated around malignant human brain tumours in association with reduced extracellular volume, which may restrict the flow of extracellular fluid from the tumour bed into the brain parenchyma. Elimination of excess fluid leaking into brain parenchyma requires passage across three AQP4-rich barriers: a) the glia limitans externa, b) the glia limitans interna/ependyma, and c) the blood-brain barrier. Modulation of the expression and/or function of endothelial tight junction proteins and aquaporins may provide novel therapeutic options for reducing brain tumour oedema.

Expression of aquaporin water channels in mouse spinal cord.

Aquaporins (AQPs) are membrane proteins involved in water transport in many fluid-transporting tissues. Aquaporins AQP1, AQP4, and AQP9 have been identified in brain and hypothesized to participate in brain water homeostasis. Here we use reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunohistochemistry to describe the expression and immunolocalization of AQPs in adult mouse spinal cord. AQP4 was expressed in glial cells, predominantly in gray matter, and in astrocytic end-feet surrounding capillaries in spinal cord white matter. AQP9 expression extensively co-localized with glial fibrillary acidic protein-immunoreactive astrocytes, located predominantly in the white matter. AQP5 was detected by RT-PCR but not by immunohistochemical analysis. Interestingly, AQP8 was detected primarily in ependymal cells lining the fluid-filled central canal. The aquaporin expression pattern in spinal cord suggests involvement in water homeostasis and diseases associated with abnormal water fluxes such as spinal cord injury and syringomyelia.

[Myeloproliferative disorders]. / Myeloproliferative Syndrome.

Myeloproliferative disorders are caused by abnormalities of hematopoietic stem cells leading to uncontrolled proliferation of one or more cell lines in the blood. Besides sharing common clinical and hematologic features they are characterized by clonal hematopoiesis and genetic instability, resulting in a disease-specific rate of transformation into acute leukemia. This review discusses relevant clinical and prognostic aspects as well as current diagnostic and therapeutic procedures of polycythemia vera, essential thrombocythemia and chronic idiopathic myelofibrosis.

Endovascular embolectomy of acute basilar artery occlusion.

Acute basilar artery occlusion has a mortality rate approaching 90%. The authors describe a case of acute basilar artery occlusion managed successfully with endovascular embolectomy. A 31-year-old man sought treatment for confusion, dysarthria, and right-sided weakness. He soon became unresponsive and was found to have a vertebral artery dissection and an associated basilar artery embolism. The dissection was managed with endovascular stenting, and the basilar artery embolus was removed with a clot retriever at 7 hours. The patient recovered without neurologic deficit.

Molecular biology of glioma tumorigenesis.

Gliomas are the most common intracranial malignant tumors in humans, and high-grade gliomas in particular pose a unique challenge due to their propensity for proliferation and tissue invasion. Our understanding of glioma oncogenesis, proliferation, and invasion has been greatly advanced in the past 10 years as researchers have gained a better understanding of the molecular biology of these tumors. This article highlights glioma histopathology, as well as cytogenetic and molecular alterations associated with the pathogenesis of human gliomas. It is hoped that better understanding of the molecular pathogenesis of gliomas will improve tumor classification as well as lead to novel targets for therapy and prognostic markers.

Aquaporin-1 expression in human glial tumors suggests a potential novel therapeutic target for tumor-associated edema.

Aquaporins are membrane proteins involved in water transport in many fluid-transporting tissues. The objective of this study was to investigate the expression of aquaporins in malignant glial tumors associated with cerebral edema. Eighteen human glial tumors were obtained from the UCSF Neurosurgery Tissue Bank. Aquaporin-1 (AQP1) expression was evaluated via Western blot and immunohistochemistry. Intense upregulation of AQP1 expression was found in all glioblastomas. The robust expression of aquaporins in glioblastomas suggests a pathologic role for these membrane water channels, and raises the possibility that selective AQP inhibition might offer a new therapeutic option for tumor-associated cerebral edema.

Biochemical analysis of cybrids expressing mitochondrial DNA from Contursi kindred Parkinson's subjects.

Complex I activity is reduced in cytoplasmic hybrid (cybrid) cell lines that contain mitochondrial DNA (mtDNA) from sporadic Parkinson's disease (PD) patients. This implies that mtDNA aberration occurs in sporadic PD. To assess the integrity of mtDNA in autosomal dominant PD arising from mutation of the alpha-synuclein gene, we transferred mitochondrial genes from PD-affected members of the Italian-American Contursi kindred to cells previously depleted of their endogenous mtDNA. Unlike cybrid cell lines expressing mtDNA from persons with sporadic or maternally inherited PD, the resultant Contursi cybrid lines did not manifest complex I deficiency, indicating that in Contursi PD mtDNA integrity is relatively preserved. Compared to control cybrids, however, Contursi cybrid lines did show some evidence of oxidative stress. For reasons that are unclear, at least a limited amount of mtDNA damage may nevertheless develop in PD patients with alpha-synuclein mutation.

BDNF and epilepsy: too much of a good thing?

Various studies have shown that brain-derived neurotrophic factor (BDNF) increases neuronal excitability and is localized and upregulated in areas implicated in epileptogenesis. Seizure activity increases the expression of BDNF mRNA and protein, and recent studies have shown that interfering with BDNF signal transduction inhibits the development of the epileptic state in vivo. These results suggest that BDNF contributes to epileptogenesis. Further analysis of the cellular and molecular mechanisms by which BDNF influences excitability and connectivity in adult brain could provide novel concepts and targets for anticonvulsant or anti-epileptogenic therapy.

[Neonatal alloimmune thrombocytopenia due to a rare anti-HPA-1b antibody]. / Neonatale Alloimmunthrombozytopenie durch einen Antikörper gegen das selten immunogene HPA-1b.

Foetal and neonatal alloimmune thrombocytopenia is caused by transplacental transfer of antibodies directed against platelet antigens and affects approximately 1 in 1000-2500 neonates. Clinically relevant complications are the intracranial haemorrhages that occur in 10-20% of cases. 20 platelet antigen systems are currently known. However, immunisation is most frequently seen against two of these (HPA-1a and HPA-5b). Treatment options include transfusion of compatible or, if these are not available while urgently needed, random donor platelets, intravenous immunoglobulin, and steroids. We report on a case of neonatal alloimmune thrombocytopenia due to an anti-HPA-1b antibody in the third pregnancy of a 31-year-old Caucasoid woman. The infant was treated with repeated maternal and random donor platelet transfusions and with a single dose of intravenous immunoglobulin.