Use of Bevacizumab for neurological complications during initial treatment of malignant gliomas.

INTRODUCTION: High grade gliomas are the most common primary malignant brain tumours. Treatment with chemoradiation and adjuvant chemotherapy with Temozolomide may prolong survival but some patients develop complications during or soon after therapy due to radiation necrosis, oedema or tumour progression. PATIENTS: We report the use of Bevacizumab in four patients with newly diagnosed high grade gliomas who developed cerebral oedema due to tumour progression or radiation necrosis that did not respond to corticosteroids, and who were not candidates for surgical debulking. OUTCOMES: All four patients had a rapid response to treatment with bevacizumab, tolerating a decrease of the dose of corticosteroids, and were able to continue their standard therapy. CONCLUSIONS: Bevacizumab is effective in controlling some of the neurological complications from oedema, radiation necrosis, or rapid tumour progression during the initial treatment of malignant gliomas.

Changes in fecal microbiota with CFTR modulator therapy: A pilot study.

Studies have demonstrated that people with CF with pancreatic insufficiency (PI) have fecal dysbioses. Evidence suggests the causes of these dysbioses are multifactorial, and that important drivers include antibiotic exposure, dietary intake, and CF gastrointestinal tract dysfunction, including nutrient malabsorption. In this pilot study, we tested whether initiation of the CFTR modulator treatments ivacaftor (in a cohort of pancreatic sufficient (PS) people with CF and an R117H CFTR variant) or lumacaftor/ivacaftor (in a cohort of PI people with CF and an F508del variant) changed fecal measures of malabsorption or fecal microbiomes. While we identified no statistically significant fecal changes with either treatment, we detected trends in the PI cohort when initiating lumacaftor/ivacaftor towards decreased fecal fat content and towards fecal microbiomes that more closely resembled the fecal microbiota of people without PI. While these findings support a model in which nutrient malabsorption resulting from CF-induced PI drives fecal dysbiosis, they must be validated in future, larger studies of fecal microbiome and malabsorption outcomes with highly effective CFTR modulator therapies.

Continuous renewal of the axonal pathway sensor apparatus by insertion of new sensor molecules into the growth cone membrane.

BACKGROUND: Growth cones at the tips of growing axons move along predetermined pathways to establish synaptic connections between neurons and their distant targets. To establish their orientation, growth cones continuously sample for, and respond to, guidance information provided by cell surfaces and the extracellular matrix. To identify specific guidance cues, growth cones have sensor molecules on their surface, which are expressed differentially during the temporospatial progress of axon outgrowth, at levels that depend on the pattern of neural activity. However, it has not been elucidated whether a change in gene expression can indeed change the molecular composition and, hence, the function of the sensor apparatus of growth cones. RESULTS: We have constructed adenoviral gene transfer vectors of the chicken growth cone sensor molecules axonin-1 and Ng-CAM. Using these vectors, we initiated the expression of axonin-1 and Ng-CAM in rat dorsal root ganglia explants during ongoing neurite outgrowth. Using specific surface immunodetection at varying time points after infection, we found that axonin-1 and Ng-CAM are transported directly to the growth cone and inserted exclusively in the growth cone membrane and not in the axolemma of the axon shaft. Furthermore, we found that axonin-1 and Ng-CAM do not diffuse retrogradely, suggesting that the sensor molecules are integrated into multimolecular complexes in the growth cone. CONCLUSIONS: During axon outgrowth, the pathway sensor apparatus of the growth cone is continuously updated by newly synthesized sensor molecules that originate directly from the transcription/translation machinery. Changes in the expression of sensor molecules may have a direct impact, therefore, on the exploratory function of the growth cone.

Autoimmune limbic encephalitis in 39 patients: immunophenotypes and outcomes.

BACKGROUND: About 40% of patients with limbic encephalitis do not have detectable CNS antibodies. Some of these patients have immune-mediated limbic encephalitis, but their frequency is unknown. AIMS: (1) To determine the spectrum of limbic encephalitis identified on clinical grounds in a single institution, and compare it with that in patients referred for antibody analysis. (2) To correlate clinical outcomes with the cellular location of the autoantigens. METHODS: Prospective clinical case studies. Immunohistochemistry with rat brain, live hippocampal neurones, HeLa cells expressing Kv potassium channels and immunoblot. RESULTS: In 4 years, 17 patients were identified in the Hospital of the University of Pennsylvania, Philadelphia, USA, and the serum or CSF samples of 22 patients diagnosed elsewhere were also studied. 9 of our 17 (53%) patients had antibodies to known neuronal antigens (paraneoplastic or voltage gated potassium channels (VGKCs)) and 5 (29%) to novel cell-membrane antigens (nCMAg) typically expressed in the hippocampus and sometimes in the cerebellum. Considering the entire series, 19 of 39 (49%) patients had antibodies to known antigens, and 17 (44%) to nCMAg. Follow-up (2-48 months, median 19 months) was available for 35 patients. When compared with patients with antibodies to intraneuronal antigens, a significant association with response to treatment was found in those with antibodies to cell-membrane antigens in general (VGKC or nCMAg, p = 0.003) or to nCMAg (p = 0.006). CONCLUSIONS: (1) 82% of patients with limbic encephalitis prospectively identified on clinical grounds had CNS antibodies; (2) responsiveness to treatment is not limited to patients with VGKC antibodies; (3) in many patients (29% from a single institution), the autoantigens were unknown but were found to be highly enriched in neuronal cell membranes of the hippocampus; and (4) these antibodies are associated with a favourable outcome.

Serum anti-p53 antibodies and prognosis of patients with small-cell lung cancer.

BACKGROUND: Some patients with cancer develop antibodies against the p53 tumor suppressor protein. The presence of these antibodies in serum has been associated with the expression of mutant p53 by the tumor and in some studies with a poorer survival. PURPOSE: The goals of this study were to determine the prevalence of anti-p53 antibodies in the serum of patients with newly diagnosed small-cell lung cancer (SCLC) and to assess the clinical relevance of the presence of these antibodies in the serum, particularly their relationship with tumor response to treatment and with patient survival. METHODS: In this prospective study, serum was obtained from 170 patients at the time of diagnosis of SCLC who were to subsequently receive platinum- or doxorubicin-based chemotherapy at any one of four hospitals in Barcelona, Spain, from October 1991 through June 1994. Normal human sera from blood bank donors (n = 50) served as controls. The presence of anti-p53 antibodies was determined by western blot analysis with the use of purified recombinant p53 protein. As of January 1996, 96.5% of the patients had been treated and observed in the study, for a median follow-up time of 33.5 months. Survival was estimated by the Kaplan-Meier method. Cox proportional hazards regression and unconditional logistic regression analyses were conducted. All P values resulted from two-sided tests. RESULTS: Anti-p53 antibodies were detected in the serum of 27 (16%) of the 170 patients studied. None of 50 serum samples from normal individuals contained anti-p53 antibodies. Analysis of pretreatment clinical characteristics demonstrated that a weight loss of less than 5% (P = .025), a serum lactic acid dehydrogenase (LDH) level of less than 450 U/L (P = .002), and limited stage disease (i.e., tumor confined to one hemithorax, with local and regional lymph node positivity for tumor cells and/or ipsilateral pleural effusion allowed) (P < .001) were associated with a statistically significant complete response to therapy. The presence of serum anti-p53 antibodies was not associated with clinical characteristics, such as age (P = .622), functional status (P = 1.0), disease stage (P = .634), complete response to treatment (P = .572), and survival (P = .492) or with any laboratory parameters including known prognostic factors in SCLC, such as serum sodium or LDH concentration (P values of .731 and .246, respectively). CONCLUSIONS AND IMPLICATIONS: The presence of anti-p53 antibodies in the serum of patients with newly diagnosed SCLC was not associated with any clinical characteristics or prognostic markers, suggesting that, in this context, the measurement of anti-p53 antibodies is not a useful prognostic marker.

DNA vaccination with HuD inhibits growth of a neuroblastoma in mice.

Some patients with small cell lung cancer (SCLC) or neuroblastoma develop an immune response against HuD, a human homologue of the Drosophila protein, elav, which is expressed in the nucleus and to a lesser degree the cytoplasm of neurons and tumor cells. This immune response is characterized by antibodies (anti-Hu) that at high titers are associated with a disease called paraneoplastic encephalomyelitis/sensory neuronopathy, in which infiltrates of T cells are found in the tumor and nervous system. Although all SCLCs express HuD, anti-Hu antibodies are identified in only 17% of patients with SCLC, usually at low titers, and are associated with indolent tumor growth. To determine whether the anti-Hu immune response causes indolent tumor growth, we developed an animal model using HuD DNA immunization. We found that a plasmid coding for a secreted form of HuD induced a strong and specific anti-Hu response. Immunized animals were challenged by s.c. implantation of a neuroblastoma cell line that constitutively expresses HuD. When compared with controls, mice immunized with the secreted HuD showed significant tumor growth inhibition (51% reduction volume; P = 0.0012), and 14% of them had complete tumor rejection. Tumors from these animals showed three times more CD3+ lymphocytic infiltrates than those from control mice and had a higher CD8+:CD4+ ratio. None of the animals developed neurological deficits or neuropathological evidence of nervous system pathology. In this mouse model of neuroblastoma, DNA immunization with HuD resulted in tumor growth inhibition but did not induce neurological disease. This model closely mimics the clinical course of more indolent tumor growth seen in patients with the anti-Hu immune response.

Simplified production of a recombinant human angiostatin derivative that suppresses intracerebral glial tumor growth.

Angiostatin is an endogenous inhibitor of tumor neovascularization that inhibits the proliferation of endothelial cells. Production of sufficient quantities of biologically active angiostatin by the enzymatic cleavage of plasminogen has proven difficult in that it has delayed clinical testing. We have cloned, expressed, and purified a recombinant human angiostatin derivative (K1-3) using a mammalian expression system. Through the addition of a secretory signal and polyhistidine sequence tag, K1-3 can be purified from post-culture medium by simple column chromatography. Purified K1-3 protein is apparently folded in an active conformation, as evidenced by its ability to bind to lysine-Sepharose. In vitro, recombinant K1-3 significantly suppressed endothelial cell proliferation in a dose-dependent manner with an IC50 of 50 nM. Using an animal model of intracranial brain tumors in immune-competent rats, systemic administration of purified recombinant K1-3 resulted in up to 85% suppression of tumor growth (P = 0.011). Growth suppression was accompanied by a 32% decrease (P = 0.01) in tumor neovascularization. This study demonstrates a simple method to produce a biologically active recombinant angiostatin derivative. The ability to suppress intracerebral tumor growth after systemic administration suggests that K1-3 is likely to have therapeutic value in the treatment of malignant glial tumors.

T-cell receptor analysis in anti-Hu associated paraneoplastic encephalomyelitis.

OBJECTIVE: To analyze the T-cell receptor (TCR) repertoire in the inflammatory infiltrates of the nervous system and tumor of patients with anti-Hu associated paraneoplastic encephalomyelitis and sensory neuronopathy (PEM/SN). BACKGROUND: In PEM/SN, the pathogenic role of the infiltrating T cells is speculative. TCR analysis may establish whether these lymphocytes are attracted nonspecifically by a proinflammatory environment or are driven by a specific antigen or superantigen. METHODS: We examined frozen tissues of seven patients with PEM/SN using immunohistochemical and PCR analysis. Of 62 tissue blocks from seven patients, 19 blocks from five patients had >100 CD3+ cells per section infiltrating the nervous system or tumor. These infiltrates allowed screening of the TCR Vbeta family repertoire using a panel of 18 antibodies that recognize family-specific regions of most TCR Vbeta families against which antibodies have been generated. To distinguish between antigen-driven clonal and superantigen-driven family expansion, we extracted RNA from frozen tissue and performed reverse transcriptase (RT)-PCR analysis followed by subcloning and sequencing of the antigen-specific CDR3 region of the TCR Vbeta chain. RESULTS: All five patients showed a limited Vbeta repertoire. An overrepresentation (>10% of total CD3+) of certain Vbeta families was identified in three patients (as high as 45% of total CD3+), which consisted mainly of CD8 + cells. CDR3 sequences obtained from one patient revealed an in situ expansion of two clones in the amygdala (one at a frequency of 57%) and four clones in the tumor. CONCLUSION: These findings suggest that an antigen-driven oligoclonal cytotoxic T-cell response plays a role in the pathogenesis of anti-Hu associated PEM/SN.

Gene transfer of wild-type p53 results in restoration of tumor-suppressor function in a medulloblastoma cell line.

The replacement of functional genes into cells that lack genes or have mutant genes is the basis of gene therapy. In cancer, where cells often have multiple genetic defects, the replacement of critical genes may suffice to suppress cell growth or induce cell death. The high frequency of mutations of the p53 tumor-suppressor gene in human cancers, including primary brain tumors, suggests that p53 plays a critical role in carcinogenesis and tumor progression. We report the successful transfer of the wild-type p53 gene using a defective herpes simplex viral vector into a human medulloblastoma cell line containing a mutant copy of p53. Upon gene transfer, we detected novel expression of wild-type p53 protein in the cells. In addition, the p53 protein was functionally active, since gene transfer resulted in increased levels of mdm2 proteins and induced cell cycle arrest of the majority of transduced cells. To our knowledge, this is the first report of the use of this vector system to carry wild-type p53. We conclude that defective herpes simplex viral vectors can transfer and express p53 in human primary brain tumor cells in vitro, restoring wild-type p53 tumor-suppressor functions.

Cerebellar degeneration and autoimmunity to zinc-finger proteins of the cerebellum.

The serum of a patient with subacute cerebellar dysfunction was used to probe a cDNA expression library and isolate two genes: Zic1 (zinc-finger of the cerebellum) and Zic4. The patient had intrathecal synthesis of Zic antibodies, suggesting that the Zic proteins were autoantigens of the neurologic disorder. The Zic proteins are involved in cerebellar development and are reported as being preferentially expressed by medulloblastomas. It was found that the expression of Zic proteins is enriched in, but not limited to, medulloblastomas and primitive neuroectodermal tumors.

Antibodies against the calcium channel beta-subunit in Lambert-Eaton myasthenic syndrome.

The sera of patients with Lambert-Eaton myasthenic syndrome (LEMS) contain autoantibodies against several extracellular and intracellular components of the voltage-gated calcium channel (VGCC)/synaptic vesicle release complex. An example of the latter are anti-beta-subunit antibodies (anti-MysB antibodies). We constructed a full-length cDNA clone of a human VGCC beta-subunit to produce purified beta-subunit fusion protein (MysB protein). Using this protein, we demonstrated that anti-beta-subunit antibodies are present in the sera of 23% of LEMS patients and only, in low titer, in 2% of small cell lung cancer patients without LEMS. The presence of anti-beta-subunit antibodies was closely associated with high titers of P/Q- and N-type VGCC antibodies. Immunization of rats with the purified MysB protein induced high antibody titers, but no signs of neurologic dysfunction were found. We conclude that anti-beta-subunit antibodies are not likely to interfere with ion channel function, but their presence could explain the cross-reactivity of LEMS sera with several subtypes of VGCCs and the lack of correlation between anti-VGCC antibody titer and clinical severity of disease.

Absence of antibodies to non-NMDA glutamate-receptor subunits in paraneoplastic cerebellar degeneration.

OBJECTIVE: To determine whether patients with antineuronal antibody-associated paraneoplastic cerebellar degeneration (PCD) harbor antibodies to non-N-methyl-D-aspartate glutamate receptors (GluRs) in their serum. BACKGROUND: A recent study identified antibodies to GluRs in the serum of patients with PCD. METHODS: Sera of 35 patients with PCD (20 anti-Yo, 5 anti-Ri, 5 anti-Tr, and 5 anti-Hu) were examined by immunohistochemistry and immunoblot techniques. The expression of GluRs was obtained after transfection of 293T cells with cDNA plasmids corresponding to GluR1, GluR2, GluR3, GluR4, GluR6, and GluR7. The tumors of four patients with anti-Yo-associated PCD and nine ovarian carcinomas from patients without PCD were examined for the expression of GluRs. RESULTS: The expression of each GluR subunit was confirmed using affinity-purified antibodies against the corresponding GluRs and with whole sera from two rabbits immunized with GluR3. Thirty-two sera from patients with PCD were negative and 3 showed equivocal reactivity with 293T cells expressing different GluRs. None of the 35 sera had a pattern of reactivity characteristic of any GluR antibody on immunohistochemistry of sections of rat brain. Eleven of 14 tumors did not express GluRs; only some cells of one paraneoplastic tumor expressed GluRs. CONCLUSIONS: That patients with antibody-associated PCD (anti-Yo, -Ri, -Tr, and -Hu) harbor GluR antibodies in their sera is unlikely. GluR antibodies cannot be used as markers of paraneoplastic neurologic disorders.

Differential affinities of molindone, metoclopramide and domperidone for classes of [3H]spiroperidol binding sites in rat striatum: evidence for pharmacologically distinct classes of receptors.

Rat striatum contains two populations of dopaminergic [3H]spiroperidol binding sites. The two populations are similar in their affinities for chlorpromazine and dopamine. Only one population, that with a somewhat higher affinity for spiroperidol itself, exhibits high affinity for the selective D2 antagonists molindone, metoclopramide and domperidone. Hence, this population may represent D2 receptor sites. The other larger population may represent either a separate class of receptor sites or a different form of D2 receptor sites.

The clinical spectrum and pathogenesis of paraneoplastic disorders of the central nervous system.

Paraneoplastic neurologic disorders (PND) refer to neurologic disorders of unknown cause that occur at higher frequency in patients with cancer than in the general population. There is increasing evidence that many of these disorders are immune mediated and associated with cytotoxic antitumor immunity. The identification of the immune responses in these patients facilitates the diagnosis of the PND and has led to the cloning and characterization of the target antigens in the nervous system and tumor.

Stimulation of adenylate cyclase in rat striatum by pergolide: influence of GTP.

Pergolide stimulates adenylate cyclase activity in homogenates of rat striatum. In contrast, bromocriptine and lisuride are inactive. GTP enhances the stimulation produced by pergolide and has no effect on the other ergots tested. The stimulation produced by pergolide is inhibited by haloperidol but not by molindone. It is concluded that pergolide acts as an agonist at dopaminergic receptors coupled to adenylate cyclase in rat striatum.

Alpha-1-acid (AAG, orosomucoid) glycoprotein: interaction with bacterial lipopolysaccharide and protection from sepsis.

In the acute phase response to a variety of insults a rise in the levels of the acute phase proteins, including elevations of serum alpha 1 acid glycoprotein (AAG) occurs. The physiological role of AAG is unknown, however, the time course of AAG production in the acute phase response together with its strong affinity for basic compounds suggests that AAG may function as an immune modulator to bind both exogenous and endogenous inflammatory mediators. Using E. coli lipopolysaccharide (LPS), an initiator of the acute inflammatory response associated with septic shock, we demonstrate that AAG-LPS complexes can activate mouse macrophages in vitro. In a mouse animal model of sepsis, AAG was shown to protect against meningococcal endotoxin. To pursue the mechanism of AAG action we demonstrated that AAG interacts directly with LPS using dynamic light scattering particle sizing and particle mobility. We also determined the enthalpy of interaction of AAG and LPS and showed that AAG leads to agglutination of LPS impregnated rabbit red blood cells. These studies suggest that AAG may function as an immune-modulator in the acute phase response, possibly by counter-regulating the activity of macrophage pro-inflammatory cytokines.

[Differential diagnosis of encephalitis due to anti-NMDA receptor antibodies]. / Diagnóstico diferencial en la encefalitis por anticuerpos contra el receptor NMDA.

INTRODUCTION: Anti-NMDA receptor (NMDAR) encephalitis usually develops as a multistage syndrome with a broad differential diagnosis. PATIENTS: We report 2 patients with anti-NMDAR encephalitis and a clinical picture typical of this disorder but whose initial evaluation suggested other aetiologies. DISCUSSION: The frequent development of this disorder in young individuals presenting with psychiatric manifestations often suggests other diagnostic possibilities, most commonly viral encephalitis, psychiatric disorders, and neuroleptic malignant syndrome. In addition, several less clearly defined syndromes or descriptively reported disorders in adult and paediatric patients were likely cases of anti-NMDAR encephalitis. CONCLUSIONS: Anti-NMDAR encephalitis should be considered in young individuals with subacute presentation of psychiatric symptoms, abnormal movements, and autonomic dysfunction. The clinical and immunological characterization of this disorder has lead to the identification of new antibodies that affect memory, learning, behaviour and psychosis.