Essential competencies in palliative medicine for neuro-oncologists

Palliative care is an approach to practicing medicine that addresses symptom management, alleviation of pain, assessment of psychosocial and spiritual distress or suffering, and practical support for patients and their caregivers with a goal of improving quality of life for patients with serious and life-threatening illnesses. Although palliative care has gained acceptance as an important part of comprehensive cancer care at the end of life, early integration of palliative care is less common. Patients with high-grade malignant gliomas have an invariably poor prognosis and high morbidity. With short survival times and complex neurological and systemic symptoms, these patients require palliative care from the time of diagnosis. In this review, we highlight the palliative care needs of neuro-oncology patients at diagnosis, during treatment, and at the end of life. We identify some of the barriers to incorporation of palliative care in standard neuro-oncology practice and equate competency in neuro-oncology with competency in the basic tenets of palliative medicine.

Emerging therapies for glioblastoma

IMPORTANCE

Glioblastoma is the most common primary malignant brain tumor, but despite multimodal treatment with surgery, radiotherapy, and temozolomide chemotherapy, the prognosis is poor, with a median survival of 16 to 19 months and poor quality of life throughout the disease course. New treatments are needed.

EVIDENCE REVIEW

Articles were identified through a search of PubMed references from March 2005 through January 2014, using the terms glioblastoma, glioma, malignant glioma, and brain neoplasm, as well as by search of the authors' files. Clinical trials were identified in the Clinicaltrials.gov registry.

FINDINGS

Advances in the understanding of the molecular biology of glioblastoma are being rapidly translated into innovative clinical trials, capitalizing on improved genomic, epigenetic, transcriptional, and proteomic characterization of glioblastomas as well as host factors, including the brain microenvironment and immune system interactions. Therapies targeting tumor growth factor receptors and downstream pathways, angiogenesis, modulation of cancer stemlike cells, cell cycle regulation, oncolytic viruses, new radiotherapy techniques, and immunotherapy, including vaccines and modulation of immune checkpoints (eg, programmed cell death 1 and cytotoxic T-lymphocyte antigen 4), are under investigation. In addition to novel agents, techniques to circumvent the blood-brain barrier to facilitate central nervous system drug exposure are being developed.

CONCLUSIONS AND RELEVANCE

Glioblastoma is an aggressive tumor with heterogeneous molecular features and complex host interactions, many of which are amenable to therapeutic intervention. Meaningful treatment advances will depend on identifying agents that target mechanistic vulnerabilities that are relevant to specific subgroups of patients; increasing patient enrollment into clinical trials is essential to accelerate the development of patient-tailored treatments.

Regulatory T cells are not a strong predictor of survival for patients with glioblastoma

BACKGROUND

Regulatory T cells (Tregs) are potentially prognostic indicators in patients with glioblastoma. If differences in frequency of Tregs in tumor or blood account for substantial variation in patient survival, then reliably measuring Tregs may enhance treatment selection and improve outcomes.

METHODS

We measured Tregs and CD3+ T cells in tumors and blood from 25 patients with newly diagnosed glioblastoma. Tumor-infiltrating Tregs and CD3+ T cells, measured by quantitative DNA demethylation analysis (epigenetic qPCR) and by immunohistochemistry, and peripheral blood Treg proportions measured by flow cytometry were correlated with patient survival. Additionally, we analyzed data from The Cancer Genome Atlas (TCGA) to correlate the expression of Treg markers with patient survival and glioblastoma subtypes.

RESULTS

Tregs, as measured in tumor tissue and peripheral blood, did not correlate with patient survival. Although there was a correlation between tumor-infiltrating Tregs expression by epigenetic qPCR and immunohistochemistry, epigenetic qPCR was more sensitive and specific. Using data from TCGA, mRNA expression of Forkhead box protein 3 (FoxP3) and Helios and FoxP3 methylation level did not predict survival. While the classical glioblastoma subtype corresponded to lower expression of Treg markers, these markers did not predict survival in any of the glioblastoma subtypes.

CONCLUSIONS

Although immunosuppression is a hallmark of glioblastoma, Tregs as measured in tissue by gene expression, immunohistochemistry, or demethylation and Tregs in peripheral blood measured by flow cytometry do not predict survival of patients. Quantitative DNA demethylation analysis provides an objective, sensitive, and specific way of identifying Tregs and CD3+ T cells in glioblastoma.

Diagnosis of probable psychogenic nonepileptic seizures in the outpatient clinic: does gender matter?

Psychogenic nonepileptic seizures (PNESs) are paroxysmal events of altered behavior that outwardly resemble epilepsy but are caused by psychiatric disease. The diagnosis of probable PNESs can be made in the outpatient clinic prior to video-EEG monitoring by identification of specific PNES predictors and specific elements of seizure semiology from the clinical history. Since psychiatric disease may have distinct mechanisms between women and men, the objective of this study was to determine if gender-specific differences exist in PNES predictors and PNES semiology. Such differences could be used to optimize the accuracy of outpatient diagnosis of probable PNESs. Medical records of male and female patients with video-EEG diagnosis of definite PNESs were retrospectively reviewed for occurrence of PNES predictors. In addition, PNES semiology was analyzed de novo from video-EEG records and categorized into previously established semiology clusters. Eighty-six patients were included in the analysis (59 women and 27 men). We found significantly lower rates of reported physical and sexual abuse, lower rates of previous psychiatric diagnosis, and lower rates of chronic pain in male patients with no significant differences in rates of other PNES predictors. Furthermore, we found no difference in PNES semiology between men and women, with both groups experiencing similar rates of major motor, minor motor, and nonmotor semiology. In conclusion, our results lend support to the idea that distinct risk factor criteria but similar semiology criteria should be used for the diagnosis of probable PNESs in the outpatient clinic in men and women.

Vaccine-based immunotherapy for glioblastoma

Glioblastoma remains the most lethal human brain tumor, despite the advent of multimodal treatment approaches. Because immune tolerance plays an important role in tumor progression, adding immunotherapy has become an attractive and innovative treatment approach for these aggressive tumors. Several early-phase clinical trials have demonstrated that vaccine-based immunotherapies, including dendritic cell therapy, peptide-based vaccines and vaccines containing autologous tumor lysates, are feasible and well tolerated. These trials have revealed promising trends in overall survival and progression-free survival for patients with glioblastoma, and have paved the way for ongoing randomized controlled trials.

Immunotherapy for the treatment of glioblastoma

Glioblastoma, the most aggressive primary brain tumor, thrives in a microenvironment of relative immunosuppression within the relatively immune-privileged central nervous system. Despite treatments with surgery, radiation therapy, and chemotherapy, prognosis remains poor. The recent success of immunotherapy in the treatment of other cancers has renewed interest in vaccine therapy for the treatment of gliomas. In this article, we outline various immunotherapeutic strategies, review recent clinical trials data, and discuss the future of vaccine therapy for glioblastoma.

An alternative method of endotracheal intubation of common marmosets (Callithrix jacchus)

Endotracheal intubation was carried out in 11 common marmosets (Callithrix jacchus). A commercially available tilting stand and a Miller laryngoscope blade were used to visualize the larynx. Anaesthesia was induced with alphaxalone (10.6 ± 1.6 mg/kg intramuscularly, followed by 3.2 ± 1.2 mg/kg intravenously). The diameter of the proximal trachea easily fitted an endotracheal tube made from readily available material (a 12 G 'over the needle' catheter). Once the tip of the endotracheal tube was at the level of the vocal folds, the tube had to be gently rotated through a 180° angle in order to pass through the larynx into the trachea. Assessment of the dimensions of the larynx and trachea, and comparison with external anatomical features of the animals (n = 10) showed that the length of the trachea could be predicted by multiplying the craniosacral length of the marmoset by a factor of 0.42.

Benign prostatic hyperplasia presenting with renal failure--what is the role for transurethral resection of the prostate (TURP)?

The aim of the study was to determine the role of transurethralresection of prostate (TURP) in normalising renal function in men presenting with obstructive renal failure secondary to benign prostatic hyperplasia. We reviewed the cases of 14 men who presented in the last 5 years with renal impairment associated with symptoms of bladder outflow obstruction and radiological evidence of obstructive uropathy. The mean serum creatinine at presentation was 632 ng/mL (range 1299 - 225). The mean age at presentation was 68.2 years (range 50 - 83 years). Duration of symptoms prior to presentation ranged between 1 - 118 months (mean 21.5 months). Following catheter insertion, all patients underwent TURP. Six of the 14 patients required dialysis prior to surgery. Histology of the resected prostate confirmed benign prostatic hypertrophy and/or hyperplasia in all cases. Patients with carcinoma of the prostate were excluded from the study. Following TURP, 2 of the 14 men (14%) failed to void spontaneously following removal of catheter - one patient performs clean self intermittent catheterization (CSIC), the other man has an in-dwelling catheter in situ. One patient died 7 months following TURP due to a myocardial infarction. However, 8 patients, (57%) remained dialysis dependent following TURP. Two of these patients have since undergone successful renal transplantation. Of the remaining 6 patients, only 3 have normal renal function with the other 3 experiencing moderately elevated serum creatinine (range 236 - 344 ng/mL). In patients presenting with renal failure due to bladder outflow obstruction, TURP restores normal voiding pattern in many cases. However renal failure due to bladder outflow obstruction tends to be more refractory and only 3 of 14 patients experienced return to normal renal function post treatment.

Renal artery aneurysm treated with ex vivo repair and autotransplantation

Renal artery aneurysms are being encountered more frequently due to a wider use of angiography. As the risk of rupture is unclear, the indications for surgery remain controversial. Despite advances in treatment, complex aneurysms often require nephrectomy for adequate excision. We report a case of an incidentally diagnosed renal artery aneurysm successfully treated with extracorporeal repair and autotransplantation. Ex vivo repair and renal autotransplantation is a safe and effective treatment for the management of complex renal artery aneurysms

Emphysematous cystitis in an elderly patient with ulcerative colitis

Emphysematous cystitis is a rare complication of lower urinary tract infections. The disease is characterized by air within the bladder wall and lumen and commonly occurs in middle-aged diabetic women. Intramural bladder gas seen on imaging is pathognomonic for this condition. The severity of the illness varies widely from cases diagnosed incidentally to patients presenting with life-threatening sepsis. We report the case of an 80-year-old non-diabetic man presenting with emphysematous cystitis after a total colectomy for ulcerative colitis.

Traumatic pseudoaneurysm of the internal carotid artery presenting with oculosympathetic palsy

BACKGROUND

Blunt internal carotid artery (ICA) injury is rare but undiagnosed can have disastrous clinical consequences.

AIM

To report a late presentation of blunt ICA injury in a young male following a road traffic accident.

RESULT

A 16-year-old male presented 11 days following a head injury with a unilateral Horner's syndrome. Imaging confirmed a pseudoaneurysm of the ICA. The patient was treated with anticoagulant therapy.

CONCLUSION

Diagnosis of ICA injury requires a high index of suspicion and presentation with unusual neurological signs following blunt trauma to the head and neck requires prompt investigation.

The effects of Neotrofin on septodentate sprouting after unilateral entorhinal cortex lesions in rats

PURPOSE

Recent research on the purine derivative of hypoxanthine Neotrofin (4-[[3-(1,6-dihydro-6-oxo-9-purin-9-yl)-1-oxopropyl]amino]benzoic acid; AIT-082) has indicated that Neotrofin treatment elevates the mRNA levels of various neurotrophic factors, including nerve growth factor (NGF), in the CNS. Several previous studies have indicated that NGF may regulate septodentate sprouting after entorhinal cortex lesions in rats. Thus, the objective of this investigation was to determine whether Neotrofin treatment would enhance lesion-induced septodentate sprouting from 4 to 15 days postlesion.

METHODS

Sham-operated rats or rats with EC lesions were injected (i.p.) with either Neotrofin (30 mg/kg) or saline (0.9%) immediately after surgery and every day thereafter until the end of the treatment regimen. Septodentate sprouting, as indicated by intensity of acetylcholinesterase (AChE) label in the dentate gyrus, was assessed with optical densitometry.

RESULTS

We observed that Neotrofin elevated the AChE-label in the outer molecular layer of the ventral dentate gyrus at 4 days postlesion and of the dorsal dentate gyrus at 15 days postlesion.

CONCLUSIONS

Neotrofin appears to have exerted limited stimulatory effects on lesion-induced sprouting by a cholinergic pathway.

The major messenger ribonucleoprotein particle protein p50 (YB-1) promotes nucleic acid strand annealing

p50, a member of the Y-box binding transcription factor family, is tightly associated with eukaryotic mRNAs and is responsible for general translational regulation. Here we show that p50, in addition to its previously described ability to melt mRNA secondary structure, is capable of promoting rapid annealing of complementary nucleic acid strands. p50 accelerates annealing of RNA and DNA duplexes up to 1500-fold within a wide range of salt concentrations and temperatures. Phosphorylation of p50 selectively inhibits DNA annealing. Moreover, p50 catalyzes strand exchange between double-stranded and single-stranded RNAs yielding a product bearing a more extended double-stranded structure. Strikingly, p50 displays both RNA-melting and -annealing activities in a dose-dependent manner; a relatively low amount of p50 promotes formation of RNA duplexes, whereas an excess of p50 causes unwinding of double-stranded forms. Our results suggest that the alteration of nucleic acid conformation is a basic mechanism of the p50-dependent regulation of gene expression.

Vector design for optimal protein expression

Many DNA constructs are generated for protein expression studies. Translational properties and mRNA stability are crucial aspects that have to be accounted for during DNA construction. An optimized vector for protein overexpression studies is described considering elements in the mature mRNA that influence translatability and stability. Recommendations regarding vector construction for Xenopus laevis embryo injection are provided, based on literature and experimental data. The 5'untranslated region (5'UTR) should be non-regulated, short, unstructured, and without AUG codons. The sequence around the start codon should match the initiation context of the species studied (ACCAUGG, for vertebrates), and the open reading frame should be cloned with its own stop codon, followed by a G or A residue. Furthermore, the 3'UTR should be non-regulated, and a strong polyadenylation signal must be included in DNA vectors. In RNA template vectors, the presence of a poly(A) or AC tail is essential for stability, as well as for translation efficiency in mRNA injection experiments. These aspects result in high-level expression of exactly the desired protein. Easily obtainable examples of the sequences [5'UTR, 3'UTR, and poly(A) signal] are suggested.

Effect of baculovirus infection on the mRNA and protein levels of the Spodoptera frugiperda eukaryotic initiation factor 4E

The cDNA sequence of eukaryotic translation initiation factor eIF4E was derived from a Spodoptera frugiperda cDNA library. Eight tryptophan residues, typical for eIF4E, are strictly conserved in the encoded 210 amino acid protein. A polyclonal antiserum detected a 26 kDa protein in lepidopteran cell lines, but not in dipteran cells. Sf21 cells have a single eIF4E gene copy, which is transcribed into a 1500 nt transcript. Infection with AcMNPV resulted in a decrease in eIF4E mRNA starting between 12 and 24 h postinfection (p.i.), while reduced eIF4E protein levels were observed at 48 h p.i. Two forms of eIF4E were recognized that differed in their iso-electric point, of which the relative abundance did not change during infection. Mutagenesis experiments using recombinant baculoviruses revealed that the variation in mobility between these two forms did not result from a difference in the phosphorylation state of Ser-202, the serine residue that corresponds with the eIF4E phosphorylation site in mammalian eIF4E.

Secretory pathway limits the enhanced expression of classical swine fever virus E2 glycoprotein in insect cells

The 3' untranslated region (UTR) is an important element that determines the level of recombinant protein expression via baculovirus vectors. Previous work using chloramphenicol acetyl transferase as reporter has shown that p10-promoter based baculovirus vectors with the authentic p10 3' UTR resulted in higher expression levels than vectors carrying an SV40 early terminator, as part of a lacZ selection cassette. To examine whether a similar increase in expression levels could be obtained for baculovirus-expressed glycoproteins, the classical swine fever virus E2 antigen was used as a model. With the authentic p10 3' UTR higher levels of E2 transcript were found than in the presence of the SV40 terminator. This higher number of transcripts was accompanied by elevated levels of intracellular, non-glycosylated E2 protein. However, the levels of intracellular glycosylated forms of E2 and of extracellular E2 were similar for both type of terminators. These results show that translation of the recombinant mRNA is not the rate limiting step in the expression of glycoproteins, but the downstream processing and secretion of the translation products.

Sequence and translation initiation properties of the xenopus TGFbeta5, PDGF-A, and PDGF-alpha receptor 5' untranslated regions

The properties of the architecturally complex Xenopus laevis TGFbeta5, PDGF-A and PDGF-alpha receptor 5'UTRs were investigated. 5' extended cDNAs were obtained by 5'RACE, resulting in long 5'UTRs (478-710 nt) with multiple upstream AUGs (3-13), andthe potential to fold into stable structures. Injection studies suggested that the cloned PDGF-alphaR 5'UTR contains an intron. Splicing at potential 5' and 3' splice sites would result in a non-complex 5'UTR of 142 nt. The above mentioned 5'UTR characteristics are inhibitory for ribosomal scanning. Indeed, relative to the beta-globin 5'UTR, the complex 5'UTRs strongly repressed initiation of protein synthesis in pre-MBT Xenopus embryos. However, later in embryogenesis, the inhibition was partly relieved. The results show temporal translational control by these 5'UTRs. Transgenic embryos showed that the 5'UTRs allowed translation throughout the embryo; spatial control could not be observed. Interestingly, a fragment in the PDGF-A 5'UTR highly similar to an element in the human PDGF-A 5'UTR is complementary to Xenopus 18S ribosomal RNA. None of these Xenopus 5'UTRs contains an IRES, as determined by injecting bicistronic constructs.

Controlled translation initiation on insulin-like growth factor 2-leader 1 during Xenopus laevis embryogenesis

A number of growth factors, whose spatio-temporal expression is essential for embryonic development, are encoded by mRNAs with a complex 5'UTR. Human insulin-like growth factor 2 mRNA contains a long (592 nucleotides) 5'UTR (IGFl1) with one upstream open reading frame and stable stem-loop structures, elements which might be important for controlled translation. To investigate whether these unusual features of IGFl1 can control translation initiation during embryogenesis, we examined the initiation efficiency on this 5'UTR during development of Xenopus laevis. The results demonstrate that IGFl1 strongly represses translation of a reporter in early embryos, compared with the Xenopus beta-globin 5'UTR. The inhibition is alleviated soon after the midblastula transition, suggesting a stimulatory effect of the transcription start. However, a similar stimulation of IGFl1-driven translation is seen in embryos in which de novo transcription was inhibited by actinomycin D. Furthermore, it is shown that up-regulation of IGFl1 activity is independent of eIF4E levels, and activity of IGFl1 is observed in all tissues of transgenic Xenopus embryos. These results indicate that post-translational modulation of a trans-acting factor enables efficient initiation on this complex 5'UTR after the midblastula transition.

Cloning and analysis of the untranslated regions of the Xenopus laevis Connexin30 mRNA

The full-length 5' and 3' untranslated regions (UTRs) of Xenopus laevis Connexin30 (Cx30) mRNA were cloned and sequenced. The Cx30 messenger contains a 148 nt 5' UTR and a 480 nt 3' UTR. Four different constructs were made to enable the analysis of the role of the Cx30 UTRs in translation efficiency and in protein localization in the early Xenopus embryo. Transcripts encoded the Green Fluorescent Protein (GFP) reporter and contained the 5' and 3' UTR of either Cx30 or globin. In vivo analyses after injection of the transcripts into one cell-stage Xenopus embryos showed that the Cx30 3' UTR enables very efficient translation. The 5' UTR was slightly inhibitory compared with the globin 5' UTR. The localization of the produced GFP was analyzed. GFP was ubiquitously expressed in all parts of the embryo. Based on this observation we conclude that neither the 5' UTR nor the 3' UTR confers specific localization of the translation of the Cx30 mRNA in the embryo.

Translational control of the Xenopus laevis connexin-41 5'-untranslated region by three upstream open reading frames

The Xenopus laevis Connexin-41 (Cx41) mRNA contains three upstream open reading frames (uORFs) in the 5'-untranslated region (UTR). We analyzed the translation efficiency of constructs containing the Cx41 5'-UTR linked to the green fluorescent protein reporter after injection of transcripts into one-cell stage Xenopus embryos. The translational efficiency of the wild-type Cx41 5'-UTR was only 2% compared with that of the beta-globin 5'-UTR. Mutation of each of the three uAUGs into AAG codons enhanced translation 82-, 9-, and 4-fold compared with the wild-type Cx41 5'-UTR. Based on these increased translation efficiencies, the percentages of ribosomes that recognized the uAUGs were calculated. Only 0.03% of the ribosomes that entered at the cap structure scanned the entire 5'-UTR and translated the main ORF. The results indicate that all uAUGs are recognized by the majority of the scanning ribosomes and that the three uAUGs strongly modulate translation efficiency in Xenopus laevis embryos. Based on these data, a model of ribosomal flow along the mRNA is postulated. We conclude that the three uORFs may play an important role in the regulation of Cx41 expression.

Identification of caspase 3-mediated cleavage and functional alteration of eukaryotic initiation factor 2alpha in apoptosis

Induction of apoptosis in a variety of cell types leads to inhibition of protein synthesis. Recently, the cleavage of eukaryotic translation initiation factor 4G (eIF4G) by caspase 3 was described as a possible event contributing to translation inhibition. Here, we report the cleavage of another initiation factor in apoptotic cells, eIF2alpha, that could contribute to regulation of translation during apoptosis. This cleavage event could be completely inhibited by pretreatment of HeLa cells with Z-VAD-fmk. In vitro analysis using purified eIF2 and purified caspases showed cleavage of eIF2alpha by caspase 3, 6, 8, and 10 but not 9. Caspase 3 most efficiently cleaved eIF2alpha and this could be inhibited by addition of Ac-DEVD-CHO in vitro. Comparison of cleavage of phosphorylated versus nonphosphorylated eIF2alpha revealed a modest preference of the caspases for the nonphosphorylated form. When eIF2. 2B complex was used as substrate, only caspase 3 was capable of eIF2alpha cleavage, which was not affected by phosphorylation of the alpha subunit. The eIF2.GDP binary complex was cleaved much less efficiently by caspase 3. Sequence analysis of the cleavage fragment suggested that the cleavage site is located in the C-terminal portion of the protein. Analysis showed that after caspase cleavage, exchange of GDP bound to eIF2 was very rapid and no longer dependent upon eIF2B. Furthermore, in vitro translation experiments indicated that cleavage of eIF2alpha results in functional alteration of the eIF2 complex, which no longer stimulated upstream AUG selection on a mRNA containing a viral internal ribosome entry site and was no longer capable of stimulating overall translation. In conclusion, we describe here the cleavage of a translation initiation factor, eIF2alpha that could contribute to inhibition or alteration of protein synthesis during the late stages of apoptosis.

Cloning and analysis of cDNAs encoding the hypusine-containing protein eIF5A of two lepidopteran insect species

Eukaryotic initiation factor eIF5A is essential for cell viability and contains a characteristic post-translational modification of a specific lysine residue into a hypusine. cDNAs with similarity to eIF5A sequences were derived from Spodoptera exigua and S. frugiperda cDNA libraries. The deduced amino acid sequences are identical for both species and predict a protein with a molecular mass of 17.5 kDa. The Drosophila melanogaster eIF5A cDNA sequence was retrieved from the Drosophila EST Project. The predicted protein is 80% similar to Spodoptera eIF5A. A single eIF5A gene copy is present in the S. frugiperda genome, which is transcribed into four different transcripts. Infection of S. frugiperda cells with a baculovirus resulted in a strong decline of all four transcripts already at 12 h after infection. In contrast, the eIF5A protein was fairly stable up to 48 h post infection.