Primary culture of central neurocytoma: a case report

Whole Exome Sequencing Identifies PHF14 Mutations in Neurocytoma and Predicts Responsivity to the PDGFR Inhibitor Sunitinib

Neurocytomas are rare low-grade brain tumors predominantly affecting young adults, but their cellular origin and molecular pathogenesis is largely unknown. We previously reported a sellar neurocytoma that secreted excess arginine vasopressin causing syndrome of inappropriate anti-diuretic hormone (SIADH). Whole exome sequencing in 21 neurocytoma tumor tissues identified somatic mutations in the plant homeodomain finger protein 14 (PHF14) in 3/21 (14%) tumors. Of these mutations, two were missense mutations and 4 caused splicing site losses, resulting in PHF14 dysfunction. Employing shRNA-mediated knockdown and CRISPR/Cas9-based knockout approaches, we demonstrated that loss of PHF14 increased proliferation and colony formation in five different human, mouse and rat mesenchymal and differentiated cell lines. Additionally, we demonstrated that PHF14 depletion resulted in upregulation of platelet derived growth factor receptor-alpha (PDGFRα) mRNA and protein in neuroblastoma SHSY-5Y cells and led to increased sensitivity to treatment with the PDGFR inhibitor Sunitinib. Furthermore, in a neurocytoma primary culture harboring splicing loss PHF14 mutations, overexpression of wild-type PHF14 and sunitinib treatment inhibited cell proliferation. Nude mice, inoculated with PHF14 knockout SHSY-5Y cells developed earlier and larger tumors than control cell-inoculated mice and Sunitinib administration caused greater tumor suppression in mice harboring PHF-14 knockout than control SHSY-5Y cells. Altogether our studies identified mutations of PHF14 in 14% of neurocytomas, demonstrate it can serve as an alternative pathway for certain cancerous behavior, and suggest a potential role for Sunitinib treatment in some patients with residual/recurrent neurocytoma.

Tumor Spheroids of an Aggressive Form of Central Neurocytoma Have Transit-Amplifying Progenitor Characteristics with Enhanced EGFR and Tumor Stem Cell Signaling

Central neurocytoma (CN) has been known as a benign neuronal tumor. In rare cases, CN undergoes malignant transformation to glioblastomas (GBM). Here we examined its cellular origin by characterizing differentiation potential and gene expression of CN-spheroids. First, we demonstrate that both CN tissue and cultured primary cells recapitulate the hierarchal cellular composition of subventricular zone (SVZ), which is comprised of neural stem cells (NSCs), transit amplifying progenitors (TAPs), and neuroblasts. We then derived spheroids from CN which displayed EGFR+/MASH+ TAP and BLBP+ radial glial cell (RGC) characteristic, and mitotic neurogenesis and gliogenesis by single spheroids were observed with cycling multipotential cells. CN-spheroids expressed increased levels of pluripotency and tumor stem cell genes such as KLF4 and TPD5L1, when compared to their differentiated cells and human NSCs. Importantly, Gene Set Enrichment Analysis showed that gene sets of GBM-Spheroids, EGFR Signaling, and Packaging of Telomere Ends are enriched in CN-spheroids in comparison with their differentiated cells. We speculate that CN tumor stem cells have TAP and RGC characteristics, and upregulation of EGFR signaling as well as downregulation of eph-ephrin signaling have critical roles in tumorigenesis of CN. And their ephemeral nature of TAPs destined to neuroblasts, might reflect benign nature of CN.

The Nutraceutical Properties of Ovotransferrin and Its Potential Utilization as a Functional Food

Ovotransferrin or conalbumin belong to the transferrin protein family and is endowed with both iron-transfer and protective activities. In addition to its well-known antibacterial properties, ovotransferrin displays other protective roles similar to those already ascertained for the homologous mammalian lactoferrin. These additional functions, in many cases not directly related to iron binding, are also displayed by the peptides derived from partial hydrolysis of ovotransferrin, suggesting a direct relationship between egg consumption and human health.

Endogenous amyloidogenesis in long-term rat hippocampal cell cultures

BACKGROUND

Long-term primary neuronal cultures are a useful tool for the investigation of biochemical processes associated with neuronal senescence. Improvements in available technology make it possible to observe maturation of neural cells isolated from different regions of the rodent brain over a prolonged period in vitro. Existing experimental evidence suggests that cellular aging occurs in mature, long-term, primary neuronal cell cultures. However, detailed studies of neuronal development in vitro are needed to demonstrate the validity of long-term cell culture-based models for investigation of the biochemical mechanisms of in vitro neuronal development and senescence.

RESULTS

In the current study, neuron-enriched hippocampal cell cultures were used to analyze the differentiation and degeneration of hippocampal neurons over a two month time period. The expression of different neuronal and astroglial biomarkers was used to determine the cytochemical characteristics of hippocampal cells in long-term cultures of varying ages. It was observed that the expression of the intermediate filament nestin was absent from cultures older than 21 days in vitro (DIV), and the expression of neuronal or astrocytic markers appeared to replace nestin. Additionally, morphological evaluations of neuronal integrity and Hoescht staining were used to assess the cellular conditions in the process of hippocampal culture development and aging. It was found that there was an increase in endogenous production of Aβ(1-42) and an increase in the accumulation of Congo Red-binding amyloidal aggregates associated with the aging of neurons in primary culture. In vitro changes in the morphology of co-existing astrocytes and cell culture age-dependent degeneration of neurodendritic network resemble features of in vivo brain aging at the cellular level.

CONCLUSION

In conclusion, this study suggests that long-term primary CNS culture is a viable model for the study of basic mechanisms and effective methods to decelerate the process of neuronal senescence.

Recidivant central neurocytoma treated with radiosurgery: a case report

Central neurocytoma is a rare intraventricular brain tumour that affects young people and presents with increased intracranial pressure secondary to obstructive hydrocephalus. Typically, it has a favourable prognosis after complete resection. In some cases the clinical course could be more aggressive. In this report, we describe a case of recurrent central neurocytoma treated with radiosurgery after two consecutive relapses. An asymptomatic radionecrosis developed after that. At the moment the patient is in complete recovery. Finally, we discuss the role of postoperative irradiation in the treatment of this rare tumour.