Colorectal cancer (CRC) is a leading cause of death worldwide, despite progress made in detection and management through surgery, chemotherapy, radiotherapy, and immunotherapy. Novel therapeutic agents have improved survival in both the adjuvant and advanced disease settings, albeit with an increased risk of toxicity and cost. However, metastatic disease continues to have a poor long-term prognosis and significant challenges remain due to late stage diagnosis and treatment failure. Biomarkers are a key tool in early detection, prognostication, survival, and predicting treatment response. The past three decades have seen advances in genomics and molecular pathology of cancer biomarkers, allowing for greater individualization of therapy with a positive impact on survival outcomes. Clinically useful predictive biomarkers aid clinical decision making, such as the presence of KRAS gene mutations predicting benefit from epidermal growth factor receptor (EGFR) inhibiting antibodies. However, few biomarkers have been translated into clinical practice highlighting the need for further investigation. We review a range of protein, DNA and RNA-based biomarkers under investigation for diagnostic, predictive, and prognostic properties for CRC. In particular, long non-coding RNAs (lncRNA), have been investigated as biomarkers in a range of cancers including colorectal cancer. Specifically, we evaluate the potential role of lncRNA plasmacytoma variant translocation 1 (PVT1), an oncogene, as a diagnostic, prognostic, and therapeutic biomarker in colorectal cancer.
Tripeptidyl peptidase 1 (TPP1) deficiency causes CLN2 disease, late infantile (or classic late infantile neuronal ceroid lipofuscinosis), a paediatric neurodegenerative disease of autosomal recessive inheritance. Patients suffer from blindness, ataxia, epilepsy and cognitive defects, with MRI indicating widespread brain atrophy, and profound neuron loss is evident within the retina and brain. Currently there are no effective therapies for this disease, which causes premature death in adolescence. Zebrafish have been successfully used to model a range of neurological and behavioural abnormalities. The aim of this study was to characterize the pathological and functional consequences of Tpp1 deficiency in zebrafish and to correlate these with human CLN2 disease, thereby providing a platform for drug discovery. Our data show that homozygous tpp1sa0011 mutant (tpp1sa0011−/−) zebrafish display a severe, progressive, early onset neurodegenerative phenotype, characterized by a significantly small retina, a small head and curved body. The mutant zebrafish have significantly reduced median survival with death occurring 5 days post-fertilization. As in human patients with CLN2 disease, mutant zebrafish display storage of subunit c of mitochondrial ATP-synthase, hypertrophic lysosomes as well as localized apoptotic cell death in the retina, optic tectum and cerebellum. Further neuropathological phenotypes of these mutants provide novel insights into mechanisms of pathogenesis in CLN2 disease. Secondary neurogenesis in the retina, optic tectum and cerebellum is impaired and axon tracts within the spinal cord, optic nerve and the posterior commissure are disorganized, with the optic nerve failing to reach its target. This severe neurodegenerative phenotype eventually results in functional motor impairment, but this is preceded by a phase of hyperactivity that is consistent with seizures. Importantly, both of these locomotion phenotypes can be assayed in an automated manner suitable for high-throughput studies. Our study provides proof-of-principle that tpp1sa0011−/− mutants can utilize the advantages of zebrafish for understanding pathogenesis and drug discovery in CLN2 disease and other epilepsies.
Pilonidal sinus disease is chronic acquired condition leading to significant morbidity and associated healthcare costs. Several techniques have been described to manage this condition with no treatment gaining universal acceptance. With the shift towards minimally invasive surgery, Video Assisted-Ablation of Pilonidal Sinus (VAAPS) and Endoscopic Pilonidal Sinus Treatment (EPiST) have gained prominence. The aim of this review is to analyse current treatment modalities and the evidence for endoscopic pilonidal sinus surgery.
We aimed to develop and validate a reliable method for stable long-term recordings of EEG activity in zebrafish, which is less prone to artifacts than current invasive techniques. EEG activity was recorded with a blunt electrolyte-filled glass pipette placed on the zebrafish head mimicking surface EEG technology in man. In addition, paralysis of agarose-embedded fish using D-tubocurarine excluded movement artifacts associated with epileptic activity. This non-invasive recording technique allowed recordings for up to one hour and produced less artifacts than impaling the zebrafish optic tectum with a patch pipette. Paralyzed fish survived, and normal heartbeat could be monitored for over 1h. Our technique allowed the demonstration of specific epileptic activity in kcnj10a morphant fish (a model for EAST syndrome) closely resembling epileptic activity induced by pentylenetetrazol. This new method documented that seizures in the zebrafish EAST model were ameliorated by pentobarbitone, but not diazepam, validating its usefulness. In conclusion, non-invasive recordings in paralyzed EAST syndrome zebrafish proved stable, reliable and robust, showing qualitatively similar frequency spectra to those obtained from pentylenetetrazol-treated fish. This technique may prove particularly useful in zebrafish epilepsy models that show infrequent or conditional seizure activity.
29 May 2015 in Human Vaccines & Immunotherapeutics
Recent experimental studies and pathological analyses of patient brain tissue samples with refractory epilepsy suggest that inflammatory processes and neuroinflammation plays a key-role in the etiopathology of epilepsy and convulsive disorders. These inflammatory processes lead to the secretion of pro-inflammatory cytokines responsible for blood-brain-barrier disruption and involvement of resident immune cells in the inflammation pathway, occurring within the Central Nervous System (CNS). These elements are produced through activation of Toll-Like Receptors (TLRs) by exogenous and endogenous ligands thereby increasing expression of cytokines and co-stimulatory molecules through the activation of TLRs 2, 3, 4, and 9 as reported in murine studies.It has been demonstrated that IL-1β intracellular signaling and cascade is able to alter the neuronal excitability without cell loss. The activation of the IL-1β/ IL-1β R axis is strictly linked to the secretion of the intracellular protein MyD88, which interacts with other cell surface receptors, such as TLR4 during pathogenic recognition. Furthermore, TLR-signaling pathways are able to recognize molecules released from damaged tissues, such as damage-associated molecular patterns/proteins (DAMPs). Among these molecules, High-mobility group box-1 (HMGB1) is a component of chromatin that is passively released from necrotic cells and actively released by cells that are subject to profound stress. Moreover, recent studies have described models of epilepsy induced by the administration of bicuculline and kainic acid that highlight the nature of HMGB1-TLR4 interactions, their intracellular signaling pathway as well as their role in ictiogenesis and epileptic recurrence.The aim of our review is to focus on different branches of innate immunity and their role in epilepsy, emphasizing the role of immune related molecules in epileptogenesis and highlighting the research implications for novel therapeutic strategies.
SUMMARY Recessive mutations in KCNJ10, which encodes an inwardly rectifying potassium channel, were recently identified as the cause of EAST syndrome, a severe and disabling multi-organ disorder consisting of epilepsy, ataxia, sensorineural deafness and tubulopathy that becomes clinically apparent with seizures in infancy. A Kcnj10 knockout mouse shows postnatal mortality and is therefore not suitable for drug discovery. Because zebrafish are ideal for in vivo screening for potential therapeutics, we tested whether kcnj10 knockdown in zebrafish would fill this need. We cloned zebrafish kcnj10 and demonstrated that its function is equivalent to that of human KCNJ10. We next injected splice- and translation-blocking kcnj10 antisense morpholino oligonucleotides and reproduced the cardinal symptoms of EAST syndrome – ataxia, epilepsy and renal tubular defects. Several of these phenotypes could be assayed in an automated manner. We could rescue the morphant phenotype with complementary RNA (cRNA) encoding human wild-type KCNJ10, but not with cRNA encoding a KCNJ10 mutation identified in individuals with EAST syndrome. Our results suggest that zebrafish will be a valuable tool to screen for compounds that are potentially therapeutic for EAST syndrome or its individual symptoms. Knockdown of kcnj10 represents the first zebrafish model of a salt-losing tubulopathy, which has relevance for blood pressure control.