UWCScholar :: Browsing by Author "Ekpo, Okobi"

Browsing by Author "Ekpo, Okobi"

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Antioxidant and apoptosis-inhibition potential of Carpobrotus edulis in a model of parkinson’s disease
(African Association of Physiological Sciences, 2018) Enogieru, A.B.; Omoruyi, S.I.; Ekpo, Okobi
Background: Parkinson’s disease (PD) is a neurological disorder resulting from the progressive loss of dopaminergic neurons. There is currently no known cure for PD, thus the search for complementary and alternative medicines capable of halting the degeneration of dopaminergic neurons is plausible. Carpobrotus edulis (CE) is an indigenous plant used in South African traditional medicine used for the treatment of a number of disease conditions including tuberculosis, diabetes mellitus and constipation. It has been suggested that CE contains bioactive compounds which are responsible for its acclaimed medicinal potential. No studies have been reported on the potential benefit of CE to the nervous system. This study was therefore done to evaluate the protective effects of CE against 1-methyl-4-phenylpyridinium (MPP+)-induced toxicity in the dopaminergic SH-SY5Y cell line, as well as its underlying mechanism. Methods: In this study, SH-SY5Y cells were treated with varying concentrations of CE and MPP+ respectively to determine the optimal concentrations of MPP+ and CE for further experiments. Thereafter, SH-SY5Y cells were pre-treated with 30 μM of CE before exposure to 2 mM of MPP+ to induce cellular damage. Cell viability was evaluated using the MTT assay, intracellular reactive oxygen species (ROS) production was determined using flow cytometry and the Hoechst nuclear staining was used to visualize apoptosis. Caspases 3/7 and 9 activity was assessed using commercially available kits. Results: MPP+ treatment induced marked cell viability, increased the number of condensed nuclei and apoptotic cells, increased ROS production, initiated caspase 9 and activated caspase 3/7 in SH-SY5Y cells. The observed effects of MPP+-induced toxicity were attenuated by the pre-treatment of SH-SY5Y cells with 30 μM of CE. Conclusion: The protective effects of CE against MPP+-induced toxicity in SH-SY5Y cells may be attributed to its antioxidant and anti-apoptotic properties.
The development of functionalized metallic nanoparticles for the treatment of brain cancer
(University of the Western Cape, 2019) Fipaza, Vincent Lukhanyiso; Ekpo, Okobi
Cancers of the nervous system often result from abnormal and uncontrolled growth of cells in nervous tissue. Glioblastoma Multiforme (GBM) and neuroblastoma (NB) are among the most common nervous system-associated cancers known to be relatively difficult to treat. GBM is an aggressive cancer in adults while NB mostly develops in infants and children younger than five years old. Current chemotherapeutic treatment options for GBM and NB have a number of drawbacks, including non-specific toxicity, drug resistance and the inability to cross the blood-brain barrier (BBB). Therefore, there is a need to develop new treatment options that can cross the BBB with minimal or no side effects to normal neural tissues. Gold (Au) and platinum (Pt) nanoparticles (NPs) have been shown to play a role in drug delivery by crossing the BBB to selectively target cancer tissue. However, these metallic nanoparticles have a short life span in the circulatory system and often elicit immune reactions. The functionalization of nanoparticles with polyethylene glycol (PEG) helps to improve their stability and biocompatibility. The aim of this study was therefore to develop PEGylated metallic nanoparticles and investigate their potential in vitro cytotoxic effects on SH SY5Y (NB) and U87 (GBM) cell lines.
Differential sensitivity of two endothelial cell lines to hydrogen peroxide toxicity: Relevance for in vitro studies of the blood–brain barrier
(MPDI, 2020) Alamu, Olufemi; Rado, Mariam; Ekpo, Okobi
Oxidative stress (OS) has been linked to blood–brain barrier (BBB) dysfunction which in turn has been implicated in the initiation and propagation of some neurological diseases. In this study, we profiled, for the first time, two endothelioma cell lines of mouse brain origin, commonly used as in vitro models of the blood–brain barrier, for their resistance against oxidative stress using viability measures and glutathione contents as markers. OS was induced by exposing cultured cells to varying concentrations of hydrogen peroxide and fluorescence microscopy/spectrometry was used to detect and estimate cellular glutathione contents. A colorimetric viability assay was used to determine changes in the viability of OS-exposed cells. Both the b.End5 and bEnd.3 cell lines investigated showed demonstrable content of glutathione with a statistically insignificant difference in glutathione quantity per unit cell, but with a statistically significant higher capacity for the b.End5 cell line for de novo glutathione synthesis. Furthermore, the b.End5 cells demonstrated greater oxidant buffering capacity to higher concentrations of hydrogen peroxide than the bEnd.3 cells. We concluded that mouse brain endothelial cells, derived from different types of cell lines, differ enormously in their antioxidant characteristics. We hereby recommend caution in making comparisons across BBB models utilizing distinctly different cell lines and require further prerequisites to ensure that in vitro BBB models involving these cell lines are reliable and reproducible.
Evaluating the neuroprotective effects of fermented rooibos herbal tea in Wistar rats exposed to bisphenol-A during gestation and lactation
(University of the Western Cape, 2019) Gamoudi, Bushra Khalifa; Ekpo, Okobi
Exposure to endocrine-disrupting chemicals as bisphenol A (BPA) during gestation and early postnatal life is known to disrupt normal developmental processes and alter the body’s endocrine system leading to deleterious effects in the developing central nervous system (CNS). BPA is an industrial synthetic chemical commonly used in the production of a range of polymers and consumer products, despite concerns about its safety. There is therefore the need to protect the developing CNS from potential damage through the administration of neuroprotective agents. Most medicinal plants are reported to possess significant protective potential against tissue damage through different mechanisms that prevent cell death, oxidative stress, inflammation, immunodeficiency, etc. In this study, the protective effects of fermented rooibos (Aspalathus linearis) tea against the deleterious effects of BPA were investigated. Rooibos is a herbal beverage indigenous to South Africa with widely acclaimed health benefits often linked to the bioactivity of its polyphenolic compounds, especially aspalathin. The anti-allergic, cardiovascular, antioxidant and neuroprotective effects of this herb have been previously reported hence, the present study aims to investigate if regular consumption of rooibos tea during pregnancy and lactation could protect the developing brain from the deleterious effects of BPA in a Wistar rat model. A total of 40 three-month old adult female pregnant dams, with an average weight of 250g, were divided into four groups (n=10). Group 1 control rats received 9% normal saline ad libitum; group 2 rats received 400μg/kg/day BPA only; group 3 rats received 20% fermented rooibos tea as well as 400μg/kg/day BPA, while group 4 rats received ad libitum 20% fermented rooibos tea only. Offspring rats were housed in the same cages as the dams and only separated after weaning on postnatal day (PND) 21. Neurobehavioural assessment using the open field test was done on postnatal day (PND) 42 after which the final body masses were taken before the rats were decapitated under deep anaesthesia, and the desired CNS parts carefully dissected out and processed for histological, biochemical and immunohistochemical studies. The results obtained showed that there was significant impairment of neurobehavioural activity, decreased cerebral and cerebellar antioxidant enzyme activity, reduced hippocampal CA1 length, significant loss of cerebellar Purkinje cells and significant astrocyte activation demonstrated by increased glial fibrillary acidic protein (GFAP) activity in experimental rats exposed to BPA only. However, co-administration of rooibos tea significantly attenuated the BPA-induced distortions. Taken together, these findings suggest that rooibos could be a potent neuroprotective agent against BPA-induced structural, functional and biochemical alterations in the developing CNS.
In vitro neuroprotective effects of boophone disticha, brunsvigia bosmaniae and strumaria truncata extracts in sh-sy5y cells.
(University of Western Cape, 2021) Kangwa, Tusekile Sarah; Ekpo, Okobi; Hiss, Donavon
Parkinson's disease (PD), the second most common neurodegenerative disorder after Alzheimer's disease, is one of the leading disability disorders with about 10 million people affected worldwide. The pathological hallmarks of PD are defined by the loss of dopaminergic neurons in the substantia nigra pars compacta of the midbrain with its characteristic clinical motor and non-motor symptoms. However, the loss in dopaminergic neurons causes characteristic clinical manifestations, which include non-motor and motor symptoms. Damage to cholinergic neurotransmitter systems causes non-motor symptoms like sleeping disorders, depression, and a variety of other psychiatric issues, while a malfunctioning nigrostriatal dopaminergic pathway causes such motor symptoms as tremors, stiffness, and postural instability. PD symptoms usually mirror the degree of alteration to neuronal integrity in the affected parts of the brain, but the severity of progression varies with each patient.
In vitro neuroprotective potential of phyllanthin in MPP+- induced toxicity in SH-SY5Y neuroblastoma cells
(University of the Western Cape, 2023) Delport, Joshua; Ekpo, Okobi
Parkinson’s disease (PD) is the second most common age-related neurodegenerative disease after Alzheimer’s disease, with an estimated 9 million people projected to be affected worldwide by the year 2030. PD is associated with numerous motor symptoms such as tremor, bradykinesia (slowness of movements), hypokinesia (reduction in movement amplitude) and akinesia (absence of normal unconscious movements). However, in addition to these motor symptoms, several nonmotor manifestations are common, such as sensory symptoms (pain, tingling), hyposmia, sleep disturbance, depression, and cognitive impairment.
Liposomal drug delivery to brain cancer cells
(University of the Western Cape, 2015) Boltman, Taahirah; Ekpo, Okobi; Meyer, Mervin
Neuroblastomas (NBs) are the most common solid extra-cranial tumours diagnosed in childhood and characterized by a high risk of tumour relapse. Like in other tumour types, there are major concerns about the specificity and safety of available drugs used for the treatment of NBs, especially because of potential damage to the developing brain. Many plant-derived bioactive compounds have proved effective for cancer treatment but are not delivered to tumour sites in sufficient amounts due to compromised tumour vasculature characterized by leaky capillary walls. Betulinic acid (BetA) is one such naturally-occurring anti-tumour compound with minimum to no cytotoxic effects in healthy cells and rodents. BetA is however insoluble in water and most aqueous solutions, thereby limiting its therapeutic potential as a pharmaceutical product. Liposomes are self-assembling closed colloidal structures composed of one or more concentric lipid bilayers surrounding a central aqueous core. The unique ability of liposomes to entrap hydrophilic molecules into the core and hydrophobic molecules into the bilayers renders them attractive for drug delivery systems. Cyclodextrins (CDs) are non-reducing cyclic oligosaccharides which proximate a truncated core, with features of a hydrophophilic outer surface and hydrophobic inner cavity for forming host-guest inclusion complexes with poorly water soluble molecules. CDs and liposomes have recently gained interest as novel drug delivery vehicles by allowing lipophilic/non-polar molecules into the aqueous core of liposomes, hence improving the therapeutic load, bioavailability and efficacy of many poorly water-soluble drugs. The aim of the study was to develop nano-drug delivery systems for BetA in order to treat human neuroblastoma (NB) cancer cell lines. This was achieved through the preparation of BetA liposomes (BetAL) and improving the percent entrapment efficiency (% EE) of BetA in liposomes through double entrapment of BetA and gamma cyclodextrin BetA inclusion complex (γ-CD-BetA) into liposomes (γ-CD-BetAL). We hypothesized that the γ-CD-BetAL would produce an increased % EE compared to BetAL, hence higher cytotoxic effects. Empty liposomes (EL), BetAL and γ-CD-BetAL were synthesized using the thin film hydration method followed by manual extrusion. Spectroscopic and electron microscopic characterization of these liposome formulations showed size distributions of 1-4 μm (before extrusion) and less than 200 nm (after extrusion). As the liposome size decreased, the zeta-potential (measurement of liposome stability) decreased contributing to a less stable liposomal formulation. Low starting BetA concentrations were found to be more effective in entrapping higher amounts of BetA in liposomes while the incorporation of γ-CD-BetA into liposomes enhanced the % EE when compared to BetAL, although this was not statistically significant. Cell viability studies using the WST-1 assay showed a time-and concentration-dependent decrease in SK-N-BE(2) and Kelly NB cell lines exposed to free BetA, BetAL and γ-CD-BetAL at concentrations of 5-20 ug/ml for 24, 48 and 72 hours treatment durations. The observed cytotoxicity of liposomes was dependant on the % EE of BetA. The γ-CD-BetAL was more effective in reducing cell viability in SK-N-BE(2) cells than BetAL whereas BetAL was more effective in KELLY cells at 48-72 hours. Exposure of all cells to EL showed no toxicity while free BetA was more effective overall than the respective liposomal formulations. The estimated IC₅₀ values following exposure to free BetA and BetAL were similar and both showed remarkable statistically significant decrease in NB cell viability, thus providing a basis for new hope in the effective treatment of NBs.
Neuroprotective Activities of Crossyne flava Bulbs and Amaryllidaceae Alkaloids: Implications for Parkinson’s Disease
(MDPI, 2021) Ibrakaw, Abobaker; Omoruyi, Sylvester; Ekpo, Okobi
Parkinson’s disease (PD) is one of the most common neurodegenerative diseases and affects approximately 6.3 million people worldwide. To date, the treatment of PD remains a challenge, as available treatment options are known to be associated with serious side effects; hence, the search for new treatment strategies is critical. Extracts from the Amaryllidaceae plant family as well as their alkaloids have been reported to have neuroprotective potentials. This study, therefore, investigated the biological activities of Crossyne flava and its isolated alkaloids in an in vitro MPP+(1-methyl-4- phenylpyridinium) PD model using SH-SY5Y cells. The effects of the total extract as well as the four compounds isolated from Crossyne flava (i.e., pancratinine B (1), bufanidrine (2), buphanisine (3), and epibuphanisine (4)) were evaluated for cell viability, neuroprotection, levels of reactive oxygen species (ROS), adenosine triphosphate activity (ATP), and caspase 3/7 activity in SH-SY5Y cells. The results obtained showed that pre-treatment with both the extract and the isolated compounds was effective in protecting the SH-SY5Y cells from MPP+ -induced neurotoxicity and inhibited ROS generation, ATP depletion as well as apoptosis induction in the SH-SY5Y cells. The results of this study show that the Amaryllidaceae plant family may be a source of novel compounds for the treatment of neurodegenerative diseases, which validates the reported traditional uses.
Neuroprotective activities of crossyne flava bulbs and amaryllidaceae alkaloids: Implications for parkinson’s disease
(Molecules, 2021) Omoruyi, Sylvester; Ibrakaw, Abobaker; Ekpo, Okobi; Boatwright, James
Parkinson’s disease (PD) is one of the most common neurodegenerative diseases and affects approximately 6.3 million people worldwide. To date, the treatment of PD remains a challenge, as available treatment options are known to be associated with serious side effects; hence, the search for new treatment strategies is critical. Extracts from the Amaryllidaceae plant family as well as their alkaloids have been reported to have neuroprotective potentials. This study, therefore, investigated the biological activities of Crossyne flava and its isolated alkaloids in an in vitro MPP+ (1-methyl-4- phenylpyridinium) PD model using SH-SY5Y cells. The effects of the total extract as well as the four compounds isolated from Crossyne flava (i.e., pancratinine B (1), bufanidrine (2), buphanisine (3), and epibuphanisine (4)) were evaluated for cell viability, neuroprotection, levels of reactive oxygen species (ROS), adenosine triphosphate activity (ATP), and caspase 3/7 activity in SH-SY5Y cells. The results obtained showed that pre-treatment with both the extract and the isolated compounds was effective in protecting the SH-SY5Y cells from MPP+-induced neurotoxicity and inhibited ROS generation, ATP depletion as well as apoptosis induction in the SH-SY5Y cells. The results of this study show that the Amaryllidaceae plant family may be a source of novel compounds for the treatment of neurodegenerative diseases, which validates the reported traditional uses.
The potential neuroprotective effects of two South African plant extracts in hydrogen peroxide-induced neuronal toxicity
(University of the Western Cape, 2018) Gier, Megan Loran; Ekpo, Okobi
Background: Oxidative stress induced by reactive oxygen species has been strongly associated with many neurodegenerative diseases (NDDs) and many medicinal plant-derived products have been reported to exert potent antioxidant properties. Sutherlandia frutescens (SF) and Carpobrotus edulis (CE) are two indigenous South African plants with known anti-inflammatory, anti-bacterial, antioxidant and anti-cancer properties. However, the neuroprotective effects of SF and CE have not been extensively studied. Aims: This study was done to investigate the neuroprotective potentials of S. frutescens and C. edulis aqueous extracts on hydrogen peroxide (H2O2)-induced toxicity in an SH-SY5Y neuroblastoma cellular model of oxidative stress injury. Methods: The maximum non-toxic dose (MNTD) of SF and CE against SH-SY5Y cells was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Thereafter, the cells were exposed to 250 μM H2O2 for 3 hours before treatment with the determined MNTDs of SF and CE extracts respectively and the effects of the treatments on caspase-9 protease activity, intracellular ROS levels, mitochondrial membrane permeability (MMP), nitric oxide (NO) activity, intracellular calcium activity and endogenous antioxidant activity in SH-SY5Y cells was evalaluated using caspase activity kits, DCFH-DA assay, rhodamine 123 fluorescent dye, Griess reagent, Fluo-4 direct calcium reagent, Hoechst staining dye, Superoxide dismutase (SOD) colorimetric and Catalase (CAT) assays, respectively.
Radioprotective effects of rooibos herbal tea on the developing central nervous system of wistar rats
(University of the Western Cape, 2018) Alrtemi, Milod M Ahmed; Ekpo, Okobi
Background: Early postnatal radiation exposure from environmental, diagnostic or therapeutic sources is potentially deleterious to the developing nervous system resulting in oxidative stress, structural damage, altered neurochemistry, DNA damage, inflammatory stresses as well as correlating cognitive impairment during adult life. Numerous studies in literature have investigated the radioprotective effects of medicinal plants and beverages. However, only a few studies have focused on the radioprotective effects of rooibos, an indigenous South African herbal tea, well known for its many acclaimed health benefits. Aims: This study was done to investigate the diverse radioprotective potential of fermented Rooibos herbal tea (FRHT) consumed ad libitum by pregnant rats on the adult offspring rats exposed to a once-off 6 Gy dose of gamma irradiation on postnatal day 3. Methods: Twenty-four (24) adult female rats were equally divided into four groups (6 per group) as control (NS), radiation (X), tea (RT) and their combination. On PND 30, offspring rats were subjected to neurobehavioural assessment for open field and novel object recognition parameters and later sacrificed, the brain tissues removed and processed for histological, immunohistochemical and neurochemical analyses, using standard techniques. Results: Pre-treatment with FRHT showed overall protection against radiation-induced distortions in offspring rats by significantly improving exploratory activity, the frequency of central square entry, rearing episodes, cumulative freezing time and memory retention as indicated by a relatively higher recognition index. FRHT was also found to significantly improve the antioxidant defence mechanisms in the offspring rats by reversing lowered FRAP levels, increasing superoxide dismutase and catalase enzyme activities and reducing lipid peroxidation. Histological and immunohistochemical analyses showed that morphological alterations were generally attenuated in the RTX group and the high number of caspase-3 and Glial fibrillary acidic protein (GFAP)-positive cells was significantly reduced, indicating protective effects against apoptosis and gliosis. Conclusion: Taken together, our findings tend to suggest that the potential radioprotective effects of FRHT are multimodal, possibly executed through the anti-apoptotic, antioxidative, anti-gliosis and other mechanisms, as observed in this study, and this is often attributed to the high polyphenol content in Rooibos tea.
Sleep deprivation and neurological disorders
(Hindawi, 2020) Ekpo, Okobi; Bishir, Muhammed; Bhat, Abid
Sleep plays an important role in maintaining neuronal circuitry, signalling and helps maintain overall health and wellbeing. Sleep deprivation (SD) disturbs the circadian physiology and exerts a negative impact on brain and behavioural functions. SD impairs the cellular clearance of misfolded neurotoxin proteins like α-synuclein, amyloid-β, and tau which are involved in major neurodegenerative diseases like Alzheimer's disease and Parkinson's disease. In addition, SD is also shown to affect the glymphatic system, a glial-dependent metabolic waste clearance pathway, causing accumulation of misfolded faulty proteins in synaptic compartments resulting in cognitive decline. Also, SD affects the immunological and redox system resulting in neuroinflammation and oxidative stress. Hence, it is important to understand the molecular and biochemical alterations that are the causative factors leading to these pathophysiological effects on the neuronal system. This review is an attempt in this direction. It provides up-to-date information on the alterations in the key processes, pathways, and proteins that are negatively affected by SD and become reasons for neurological disorders over a prolonged period of time, if left unattended.
Synthesis of chlorotoxin functionalized metallic nanoparticles and their in vitro evaluation of cytotoxic effects in nervous system cancer cell lines
(Institute of Physics Publishing, 2024) Boltman, Taahirah; Sibuyi, Nicole Remaliah Samantha; Ekpo, Okobi; Meyer, Mervin
The treatment of glioblastoma (GB) and neuroblastoma (NB)remains a challenge, as current chemotherapies are plagued with systemic toxicity, drug resistance, and inadequate blood–brain barrier(BBB) penetration. Therefore, novel therapeutic strategies with high specificity and the capacity to bypass the BBB are required. Chlorotoxin (CTX)selectively targets gliomas and neuroectodermal tumors, hence the use of CTX-targeted nanoparticles(NPs)represents a promising therapeutic approach for nervous system (NS) cancers. Bimetallic NPs composed of two metals such as gold-platinum NPs(AuPtNPs) exhibit enhanced anticancer properties compared to single-metal NPs, however their application in studying NS tumors has been relatively limited. CTX-functionalized monometallic gold NPs(CTX-AuNPs) and bimetallic gold-platinum NPs(CTX-AuPtNPs)were synthesized in this study. The NPs were characterized by Ultraviolet-Visible Spectroscopy (UV–vis), Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM) and Fourier Transform Infra-Red Spectroscopy (FTIR). Cytotoxicity of NPs was investigated in cancer(U87 and SH-SY5Y) and non-cancer(KMST-6) cells using the water-soluble tetrazolium (WST)-1 assay. The CTX-AuNPs and CTX-AuPtNPs had a core size of∼5 nm. The CTX-AuPtNPs showed significant anticancer activity in U87 cells possibly due to the synergistic effects of combined metals. Findings obtained from this study demonstrated that CTX can be used to target NS cancers and that bimetallic NPs could be effective in their treatment. More studies are required to investigate the mechanisms of NPs toxicity, and further explore the hyperthermia treatment of NS cancer using the CTX-AuPtNPs.
Synthesis, characterization and anticancer effects of quantum dots in neuroblastoma and glioblastoma cell lines
(University of the Western Cape, 2018) Lasher, Sashca Yosima; Ekpo, Okobi
Introduction: Nanoparticles (NPs) are gaining increased popularity for cancer treatment, especially the multifunctional nanoparticles like Quantum dots (QDs) which have a wide range of applications in nanotheranostics, cell imaging and targeted drug delivery to cancerous tissue. QDs comprise of very tiny crystals of a semiconductor material (diameter: 2-10 nm) capable of producing bright, intensive and size-tuneable near-infrared fluorescence emissions. In particular, 3-mercaptopropionic acid -capped Cadmium Telluride Quantum Dots with a zinc sulphide shell (MPA-capped CdTe/ZnS QDs), are known to be very stable, highly photoluminescent, less toxic with long-lasting “fluorophore” effects, thus making them the preferred QDs for this study. Aims: To synthesize and characterize biocompatible MPA-capped CdTe/ZnS QDs to determine size range, polydispersity index (PdI), zeta (ζ) potential, photoluminescence (PL) spectra, stability in various milieus as well as to evaluate the effects of the synthesized QDs on the viability and morphology of neuroblastoma (NB) and glioblastoma (GB) cell lines using the WST-1 cell viability assay, imaging and cell cycle analysis. Materials and methods: MPA-capped CdTe/ZnS QDs were synthesized and analysed with the Zetasizer to determine ζ-potential, hydrodynamic (hd) size and PdI, while high resolutiontransmission electron microscopy (HR-TEM) was used to validate the hd size and elemental composition using energy dispersive X-ray (EDX) spectra. Pl absorption and emission spectra were obtained with a fluorometer and stability studies were done using UV-Vis spectroscopy, permitting further biological evaluation. A concentration range of 5-20μg/ml QDs was exposed to U87 and SH-SY5Y cancer cell lines to determine biological effects at different time points, using the WST-1 assay. Confocal fluorescence microscopy was used to establish uptake and cellular localization of the QDs, cell morphology was visualized with an inverted microscope while cell cycle distribution analysis was done using the C6 flow cytometer.
The effects of selective inhibitors of n-glycosylation and endoplasmic reticulum stress inducers on the expression of neuroblastoma drug resistance
(University of the Western Cape, 2017) Husein, Wejdan A.B. Mahmud; Hiss, Donavon; Ekpo, Okobi
Neuroblastoma (NB) represents 8-10% of all childhood tumours and accounts for approximately 15% of all cancer-related deaths in the paediatric population. Approximately half of newly diagnosed children with this tumour will present with metastatic disease or histologically aggressive large tumours that are at high risk for treatment failure. Since NBs are often widely disseminated and the tumours genetically heterogeneous in terms of their growth and metastatic behaviour, it is challenging to pinpoint their origin and predict disease prognosis. Several risk factors have been identified to play a role in disease progression, including age at the time of initial presentation, tumour stage, histology and ploidy of the tumour, and cytogenetic aberrations such as MYCN amplification, anaplastic lymphoma kinase (ALK), loss of heterozygosity of 11q and gain of 17q chromosomes.

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