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OBJECTIVE: Glioma is a central nervous system tumor arising from glial cells. Despite significant advances in diagnosis and treatment, most patients with high-grade gliomas have a poor prognosis. Many studies have shown that long noncoding RNAs (lncRNAs) may play important roles in the development, progression and treatment of many tumors, including gliomas. Molecularly targeted therapy may be a new direction for the adjuvant treatment of glioma. Therefore, we hope that by studying differentially expressed lncRNAs (DElncRNAs) in glioma, we can discover lncRNAs that can serve as biomarkers for glioma and provide better therapeutic modalities for glioma patients. METHODS: First, the expression of lncRNAs in 5 normal brain (NB) tissues and 10 glioma tissues was examined by RNA sequencing (RNA-seq). Next, we performed Kaplan-Meier analysis of data from The Cancer Genome Atlas (TCGA) database to assess the prognostic value of these variables. Finally, functional analysis of the DElncRNAs was performed by means of Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. RESULTS: RNA sequencing analysis revealed 85 upregulated miRNAs and 71 downregulated lncRNAs in low-grade glioma (LGG) and 50 upregulated lncRNAs and 70 downregulated lncRNAs in glioblastoma (GBM). Among them, AL355974.3 was the most upregulated lncRNA. LINC00632 was the most downregulated lncRNA. Second, LGG patients with higher AL355974.3 expression had worse overall survival according to Kaplan-Meier analysis of the TCGA database. Finally, bioinformatics analysis revealed that the target genes of these DElncRNAs were enriched in various biological processes and signaling pathways, such as cell metabolic and developmental processes. CONCLUSION: Our findings provide evidence that AL355974.3 may be a new biomarker for glioma.
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This study conducted a retrospective analysis on 107 brain glioma patients treated from January 2018 to February 2020 to assess the impact of sodium fluorescein-guided microsurgery on postoperative cognitive function and short-term outcomes. Patients were divided into two groups: a control group (n=50 patients) undergoing routine surgery and a research group (n=57 patients) receiving sodium fluorescein-guided microsurgery. The study compared postoperative total resection rates, changes in cognitive scores, and neuropeptide levels in cerebrospinal fluid between the groups. The findings revealed that the research group experienced shorter surgical time and hospitalization duration, reduced blood loss, and higher total resection rates compared to the control group. Furthermore, the research group demonstrated improvements in cognitive scores and an increase in neuropeptide levels after surgery. There was no significant difference in the comparison of the incidence of postoperative complications between the two groups. The WHO classification and preoperative performance scores were independent prognostic factors for the evaluation of 3-year survival, highlighting the clinical significance of sodium fluorescein-guided microsurgery in improving quality of life and cognitive functions of patients without compromising their long-term survival outcomes.
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Post-stroke depression (PSD) is a serious neuropsychiatric complication post stroke and leads to cognitive deficits. This study was conducted to explore the molecular mechanism of hypoxia-inducible factor-1α (HIF-1A) in cognitive dysfunction in rats with PSD. The rat model of PSD was established by middle cerebral artery occlusion, followed by 3 weeks of treatment with chronic unpredictable mild stress. The levels of miR-582-5p, HIF-1A, and neighbor of Brca1 gene (NBR1) in brain tissues were determined using RT-qPCR. The behaviors and cognitive capacity of rats were evaluated by various behavioral tests. PSD rats were injected with HIF-1A/miR-582-5p lowexpression vectors or NBR1 overexpression vectors via stereotactic method. The binding of HIF-1A to NBR1 or miR-582-5p was analyzed by chromatin immunoprecipitation and dual-luciferase assay. HIF-1A and NBR1 were highly expressed while miR-582-5p was poorly expressed in the brain of PSD rats. HIF-1A inhibition alleviated cognitive dysfunction of PSD rats. miR-582-5p was the upstream miRNA of HIF-1A, and HIF-1A specifically interacted with the NBR1 promoter to enhance NBR1 expression. miR-582-5p downregulation and NBR1 upregulation reversed the alleviative role of HIF-1A inhibition in cognitive dysfunction of PSD rats. In summary, HIF-1A inhibition may be a therapeutic target for cognitive dysfunction post PSD.
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Disfunção Cognitiva , MicroRNAs , Acidente Vascular Cerebral , Animais , Ratos , Cognição , Disfunção Cognitiva/complicações , Subunidade alfa do Fator 1 Induzível por Hipóxia , MicroRNAs/metabolismo , Acidente Vascular Cerebral/complicaçõesRESUMO
RATIONALE: Congenital factor VII deficiency is the most common among rare bleeding disorders, characterized by spontaneous or traumatic bleeding. The clinical manifestation is heterogeneous, ranging from asymptomatic phenotype to life-threatening hemorrhages. Intracranial hemorrhage is a common complication of brain tumor neurosurgery, which significantly challenges the perioperative management of patients with hemostatic defects. PATIENT CONCERNS: This report presented a 55-year-old man with congenital factor VII deficiency, who had no history of hemorrhage or family history. He underwent a craniotomy for the treatment of papillary craniopharyngioma. DIAGNOSES: The patient was diagnosed as papillary craniopharyngioma, factor VII deficiency, and atrial fibrillation. INTERVENTIONS: To prevent bleeding, a total of 8 doses of recombinant activated factor VII and 1 dose of fresh frozen plasma were administered as the perioperative replacement therapy. This scheme was guided by a pharmacodynamic evaluation, laboratory tests, and imaging examinations. OUTCOMES: No excessive surgical bleeding was observed during the 22-day treatment. The patient was found to have compound heterozygous mutations, Ala304Thr (c.910G > A) and IVS5-2A > G (c.572-2A > G), in the F7 gene. LESSONS: This is the first reported case in which surgical hemorrhage secondary to brain tumor resection was successfully controlled in the presence of congenital factor VII deficiency. Perioperative coagulation state, hemostasis, and thrombosis events should be closely observed, and the interval and dosage of recombinant factor VIIa should be adjusted accordingly.
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Neoplasias Encefálicas , Craniofaringioma , Deficiência do Fator VII , Neurocirurgia , Neoplasias Hipofisárias , Masculino , Humanos , Pessoa de Meia-Idade , Fator VIIa/uso terapêutico , Deficiência do Fator VII/diagnóstico , Craniofaringioma/complicações , Proteínas Recombinantes/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Hipofisárias/complicações , Plasma , Fator VII/genética , Fator VII/uso terapêuticoRESUMO
Research examining the potential for circulating miRNA to serve as markers for preneoplastic lesions or early-stage hepatocellular carcinoma (HCC) is hindered by the difficulties of obtaining samples from asymptomatic individuals. As a surrogate for human samples, we identified hub miRNAs in gene co-expression networks using HCC-bearing C3H mice. We confirmed 38 hub miRNAs as associated with HCC in F2 hybrid mice derived from radiogenic HCC susceptible and resistant founders. When compared to a panel of 12 circulating miRNAs associated with human HCC, two had no mouse ortholog and 7 of the remaining 10 miRNAs overlapped with the 38 mouse HCC hub miRNAs. Using small RNA sequencing data generated from serially collected plasma samples in F2 mice, we examined the temporal levels of these 7 circulating miRNAs and found that the levels of 4 human circulating markers, miR-122-5p, miR-100-5p, miR-34a-5p and miR-365-3p increased linearly as the time approaching HCC detection neared, suggesting a correlation of miRNA levels with oncogenic progression. Estimation of change points in the kinetics of the 4 circulating miRNAs suggested the changes started 17.5 to 6.8 months prior to HCC detection. These data establish these 4 circulating miRNAs as potential sentinels for preneoplastic lesions or early-stage HCC.
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Carcinoma Hepatocelular , MicroRNA Circulante , Neoplasias Hepáticas , MicroRNAs , Animais , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/patologia , MicroRNA Circulante/genética , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C3H , MicroRNAs/genética , Compostos RadiofarmacêuticosRESUMO
Galactic cosmic rays are primarily composed of protons (85%), helium (14%), and high charge/high energy ions (HZEs) such as 56Fe, 28Si, and 16O. HZE exposure is a major risk factor for astronauts during deep-space travel due to the possibility of HZE-induced cancer. A systems biology integrated omics approach encompassing transcriptomics, proteomics, lipidomics, and functional biochemical assays was used to identify microenvironmental changes induced by HZE exposure. C57BL/6 mice were placed into six treatment groups and received the following irradiation treatments: 600 MeV/n 56Fe (0.2 Gy), 1 GeV/n 16O (0.2 Gy), 350 MeV/n 28Si (0.2 Gy), 137Cs (1.0 Gy) gamma rays, 137Cs (3.0 Gy) gamma rays, and sham irradiation. Left liver lobes were collected at 30, 60, 120, 270, and 360 days post-irradiation. Analysis of transcriptomic and proteomic data utilizing ingenuity pathway analysis identified multiple pathways involved in mitochondrial function that were altered after HZE irradiation. Lipids also exhibited changes that were linked to mitochondrial function. Molecular assays for mitochondrial Complex I activity showed significant decreases in activity after HZE exposure. HZE-induced mitochondrial dysfunction suggests an increased risk for deep space travel. Microenvironmental and pathway analysis as performed in this research identified possible targets for countermeasures to mitigate risk.
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Radiação Cósmica/efeitos adversos , Complexo I de Transporte de Elétrons/metabolismo , Raios gama/efeitos adversos , Fígado/enzimologia , Mitocôndrias Hepáticas/enzimologia , Lesões Experimentais por Radiação/enzimologia , Animais , Relação Dose-Resposta à Radiação , Fígado/patologia , Masculino , Camundongos , Mitocôndrias Hepáticas/patologia , Proteômica , Lesões Experimentais por Radiação/patologia , Voo EspacialRESUMO
The space radiation environment consists of multiple species of charged particles, including 28Si ions, that may impact brain function during and following missions. To develop biomarkers of the space radiation response, BALB/c and C3H female and male mice and their F2 hybrid progeny were irradiated with 28Si ions (350 MeV/n, 0.2 Gy) and tested for behavioral and cognitive performance 1, 6, and 12 months following irradiation. The plasma of the mice was collected for analysis of miRNA levels. Select pertinent brain regions were dissected for lipidomic analyses and analyses of levels of select biomarkers shown to be sensitive to effects of space radiation in previous studies. There were associations between lipids in select brain regions, plasma miRNA, and cognitive measures and behavioral following 28Si ion irradiation. Different but overlapping sets of miRNAs in plasma were found to be associated with cognitive measures and behavioral in sham and irradiated mice at the three time points. The radiation condition revealed pathways involved in neurodegenerative conditions and cancers. Levels of the dendritic marker MAP2 in the cortex were higher in irradiated than sham-irradiated mice at middle age, which might be part of a compensatory response. Relationships were also revealed with CD68 in miRNAs in an anatomical distinct fashion, suggesting that distinct miRNAs modulate neuroinflammation in different brain regions. The associations between lipids in selected brain regions, plasma miRNA, and behavioral and cognitive measures following 28Si ion irradiation could be used for the development of biomarker of the space radiation response.
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Comportamento Animal/efeitos da radiação , Encéfalo/metabolismo , Cognição/efeitos da radiação , Metabolismo dos Lipídeos/efeitos da radiação , MicroRNAs/sangue , Silício/efeitos adversos , Irradiação Corporal Total/efeitos adversos , Animais , Radiação Cósmica/efeitos adversos , Relação Dose-Resposta à Radiação , Feminino , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Radiação IonizanteRESUMO
High-charge, high-energy ion particle (HZE) radiations are extraterrestrial in origin and characterized by high linear energy transfer (high-LET), which causes more severe cell damage than low-LET radiations like γ-rays or photons. High-LET radiation poses potential cancer risks for astronauts on deep space missions, but the studies of its carcinogenic effects have relied heavily on animal models. It remains uncertain whether such data are applicable to human disease. Here, we used genomics approaches to directly compare high-LET radiation-induced, low-LET radiation-induced and spontaneous hepatocellular carcinoma (HCC) in mice with a human HCC cohort from The Cancer Genome Atlas (TCGA). We identified common molecular pathways between mouse and human HCC and discovered a subset of orthologous genes (mR-HCC) that associated high-LET radiation-induced mouse HCC with a subgroup (mrHCC2) of the TCGA cohort. The mrHCC2 TCGA cohort was more enriched with tumor-suppressing immune cells and showed a better prognostic outcome than other patient subgroups.
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Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Neoplasias Hepáticas/genética , Radiação Ionizante , Transcriptoma , Animais , Biomarcadores Tumorais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Biologia Computacional/métodos , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Camundongos , Prognóstico , Microambiente Tumoral/genética , Microambiente Tumoral/imunologiaRESUMO
Background: Anterior inferior cerebellar artery (AICA) aneurysms are relatively rare in clinical practice, accounting for <1% of all intracranial arteries. After the diagnosis and location are confirmed by angiography, magnetic resonance, and other imaging examinations, interventional, or surgical treatment is often used, but some complex aneurysms require reconstructive surgery. Case Description: An 8-year-old male child was admitted to the hospital due to sudden disturbance of consciousness for 2 weeks. The head CT showed hematocele in the ventricular system with subarachnoid hemorrhage in the basilar cistern and annular cistern. On admission, he was conscious, answered correctly, had a soft neck, limb muscle strength was normal, and had no cranial nerves or nervous system abnormalities. A preoperative examination showed the right side of the anterior distal arteries class under the circular wide neck aneurysm, the distal anterior inferior cerebellar artery supplying a wide range of blood to the cerebellum, the ipsilateral posterior inferior cerebellar artery absent, and the aneurysm close to the VII, VIII nerves. The aneurysm was successfully treated by aneurysm resection and intracranial artery anastomosis in situ of a2 AICA-a2 AICA. Conclusions: AICA aneurysms are relatively rare; in this case, a complex wide-necked aneurysm was successfully treated by aneurysm resection and anastomosis in situ of a2 AICA-a2 AICA. This case can provide a reference for the surgical treatment of complex anterior cerebellar aneurysms.
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Future space missions will include a return to the Moon and long duration deep space roundtrip missions to Mars. Leaving the protection that Low Earth Orbit provides will unavoidably expose astronauts to higher cumulative doses of space radiation, in addition to other stressors, e.g., microgravity. Immune regulation is known to be impacted by both radiation and spaceflight and it remains to be seen whether prolonged effects that will be encountered in deep space can have an adverse impact on health. In this study, we investigated the effects in the overall metabolism of three different low dose radiation exposures (γ-rays, 16O, and 56Fe) in spleens from male C57BL/6 mice at 1, 2, and 4 months after exposure. Forty metabolites were identified with significant enrichment in purine metabolism, tricarboxylic acid cycle, fatty acids, acylcarnitines, and amino acids. Early perturbations were more prominent in the γ irradiated samples, while later responses shifted towards more prominent responses in groups with high energy particle irradiations. Regression analysis showed a positive correlation of the abundance of identified fatty acids with time and a negative association with γ-rays, while the degradation pathway of purines was positively associated with time. Taken together, there is a strong suggestion of mitochondrial implication and the possibility of long-term effects on DNA repair and nucleotide pools following radiation exposure.
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Radiação Cósmica , Metaboloma/efeitos da radiação , Exposição à Radiação , Baço/metabolismo , Baço/efeitos da radiação , Animais , Ciclo do Ácido Cítrico/efeitos da radiação , Relação Dose-Resposta à Radiação , Modelos Lineares , Masculino , Camundongos Endogâmicos C57BL , Análise Multivariada , Purinas/metabolismoRESUMO
BACKGROUND: Children's complex middle cerebral artery (MCA) aneurysm is a relatively rare occurrence. When the huge aneurysm is located in the MCA bifurcation with an inconspicuous neck and involving numerous arteries, intravascular interventional surgery or aneurysm clipping are often difficult treatment options. At this point, high flow bypass revascularization is necessary as a treatment to preserve cerebral blood flow. In recent years, the internal maxillary artery (IMA) has gradually become the mainstream donor artery of thw high flow bypass. We performed internal maxillary artery -radial artery-middle cerebral artery (IMA-RA-MCA) and superficial temporal artery-middle cerebral artery (STA-MCA) bypass as the treatment of a complex MCA bifurcation aneurysm in consideration of the patient's condition and the advantage of the IMA. According to the author, this case is the youngest reported case of IMA-RA-MCA bypass at present. CASE DESCRIPTION: A male child, 7 years and 8 months, was admitted to the hospital due to "recurrent headache for more than 9 months," DSA indicated that there was a large wide-necked aneurysm at the bifurcation of the right MCA M1 segment, with a size of about 1.16*1.58*1.32 cm. The inflow path of the aneurysm was in front of M1 bifurcation, and one outflow path originated from the aneurysm body, and another small outflow path attached to the aneurysm body. After completing the preoperative evaluation, an extended pterional approach with zygomatic osteotomy was performed to fully expose the aneurysm and IMA, harvesting the left radial artery at the same time, then a STA-MCA bypass, IMA-RA-MCA bypass, and aneurysm trapping were performed. postoperative re-examination showed that bypass vessels and the distal middle artery vessels were patent and the aneurysm disappeared, the child has no neurological dysfunction. CONCLUSIONS: IMA-RA-MCA bypass is an effective high-flow cerebral blood reconstruct scheme in the treatment of complex middle cerebral artery bifurcation aneurysms. This case can provide a reference for the surgical treatment of complex middle cerebral artery bifurcation aneurysms in children.
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Despite considerable progress in identifying health risks to crewmembers related to exposure to galactic/cosmic rays and solar particle events (SPE) during space travel, its long-term effects on the pulmonary system are unknown. We used a murine risk projection model to investigate the impact of exposure to space-relevant radiation (SR) on the lung. C3H mice were exposed to (137)Cs gamma rays, protons (acute, low-dose exposure mimicking the 1972 SPE), 600 MeV/u (56)Fe ions, or 350 MeV/u (28)Si ions at the NASA Space Radiation Laboratory at Brookhaven National Laboratory. Animals were irradiated at the age of 2.5 mo and evaluated 23.5 mo postirradiation, at 26 mo of age. Compared with age-matched nonirradiated mice, SR exposures led to significant air space enlargement and dose-dependent decreased systemic oxygenation levels. These were associated with late mild lung inflammation and prominent cellular injury, with significant oxidative stress and apoptosis (caspase-3 activation) in the lung parenchyma. SR, especially high-energy (56)Fe or (28)Si ions markedly decreased sphingosine-1-phosphate levels and Akt- and p38 MAPK phosphorylation, depleted anti-senescence sirtuin-1 and increased biochemical markers of autophagy. Exposure to SR caused dose-dependent, pronounced late lung pathological sequelae consistent with alveolar simplification and cellular signaling of increased injury and decreased repair. The associated systemic hypoxemia suggested that this previously uncharacterized space radiation-associated lung injury was functionally significant, indicating that further studies are needed to define the risk and to develop appropriate lung-protective countermeasures for manned deep space missions.
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Radiação Cósmica/efeitos adversos , Lesão Pulmonar/etiologia , Animais , Apoptose , Autofagia , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar , Proliferação de Células , Modelos Animais de Doenças , Hipóxia/sangue , Hipóxia/complicações , Hipóxia/patologia , Lesão Pulmonar/sangue , Lesão Pulmonar/patologia , Masculino , Camundongos Endogâmicos C3H , Estresse Oxidativo , Oxigênio/sangue , Pneumonia/sangue , Pneumonia/complicações , Pneumonia/patologia , Transdução de SinaisRESUMO
Estimates of cancer risks posed to space-flight crews by exposure to high atomic number, high-energy (HZE) ions are subject to considerable uncertainty because epidemiological data do not exist for human populations exposed to similar radiation qualities. We assessed the carcinogenic effects of 300 MeV/n 28Si or 600 MeV/n 56Fe ions in a mouse model for radiation-induced acute myeloid leukemia and hepatocellular carcinoma. C3H/HeNCrl mice were irradiated with 0.1, 0.2, 0.4, or 1 Gy of 300 MeV/n 28Si ions, 600 MeV/n 56Fe ions or 1 or 2 Gy of protons simulating the 1972 solar particle event (1972SPE) at the NASA Space Radiation Laboratory. Additional mice were irradiated with 137Cs gamma rays at doses of 1, 2, or 3 Gy. All groups were followed until they were moribund or reached 800 days of age. We found that 28Si or 56Fe ions do not appear to be substantially more effective than gamma rays for the induction of acute myeloid leukemia. However, 28Si or 56Fe ion irradiated mice had a much higher incidence of hepatocellular carcinoma than gamma ray irradiated or proton irradiated mice. These data demonstrate a clear difference in the effects of these HZE ions on the induction of leukemia compared to solid tumors, suggesting potentially different mechanisms of tumorigenesis. Also seen in this study was an increase in metastatic hepatocellular carcinoma in the 28Si and 56Fe ion irradiated mice compared with those exposed to gamma rays or 1972SPE protons, a finding with important implications for setting radiation exposure limits for space-flight crew members.
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Carcinoma Hepatocelular/etiologia , Radiação Cósmica/efeitos adversos , Leucemia Mieloide Aguda/etiologia , Leucemia Induzida por Radiação/etiologia , Neoplasias Hepáticas Experimentais/etiologia , Lesões Experimentais por Radiação/etiologia , Animais , Carcinoma Hepatocelular/secundário , Humanos , Ferro/efeitos adversos , Leucemia Mieloide Aguda/patologia , Leucemia Induzida por Radiação/patologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos Endogâmicos C3H , Lesões Experimentais por Radiação/patologia , Silício/efeitos adversos , Voo EspacialRESUMO
Human fetal neural stem cells (hNSCs) can be expanded in vitro by mitogens or growth factors, such as basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), and/or leukemia inhibitory factor (LIF). Their effects on proliferation rate and differentiation pattern of hNSCs, however, have not been fully characterized. In this study, we cultured hNSCs in seven regimens, including bFGF, EGF, and LIF, either alone or in combinations. Cells were maintained as neurospheres in treatment media for various periods, up to six passages. A combination of bFGF, EGF, and LIF expanded hNSCs more efficiently than any other treatment as determined by counting total cell numbers using a trypan blue exclusion assay, a WST-1 cell viability assay, and a bromodeoxyuridine incorporation flow cytometric analysis. Differentiation patterns of hNSCs expanded under different conditions were also analyzed. We reported previously that hNSCs primed in vitro with a combination of bFGF, heparin, and laminin (FHL) induced neuronal differentiation toward a cholinergic phenotype. In this study, we show that the FHL priming increases neuronal differentiation while decreasing astroglial generation in all treatment groups as determined by immunostaining. However, cells proliferated under different growth factor conditions do vary in their phenotypic differentiation patterns. Particularly, significant generation of cholinergic cells was observed only in hNSCs expanded with EGF/bFGF or EGF/bFGF/LIF, but not with other treatment regimens, even when they are exposed to the same priming procedure. Our results indicate that hNSCs are highly plastic, with their proliferation and differentiation potential dependent on different growth factor treatments.
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Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feto/citologia , Substâncias de Crescimento/farmacologia , Neurônios/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Análise de Variância , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Western Blotting/métodos , Bromodesoxiuridina/metabolismo , Contagem de Células/métodos , Células Cultivadas , Colina O-Acetiltransferase/metabolismo , DNA/metabolismo , Combinação de Medicamentos , Citometria de Fluxo/métodos , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Imuno-Histoquímica/métodos , Proteínas de Filamentos Intermediários/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nestina , Neurônios/citologia , Prosencéfalo/citologia , Células-Tronco/citologia , Sais de Tetrazólio , Fatores de Tempo , Tubulina (Proteína)/metabolismoRESUMO
We previously described a genetically unstable human fibroblast cell strain (GM2995), isolated from normal appearing skin of a xeroderma pigmentosum group C patient that repeatedly underwent changes characteristic of the transformed phenotype upon serial cultivation in vitro. In order to gain information concerning genetic changes associated with the transformation of this xeroderma pigmentosum group C cell strain, we examined the expression/function of several cell cycle regulators during its serial cultivation. A mutation in exon 8 of the P53 gene was associated with loss of function of the p53 protein and appeared at about the same time that transformation occurred. Abnormal P53 function was confirmed by the lack of upregulation of p53 as well as activation of its downstream effectors p21Waf1 and HDM2 in high passage cells exposed to either gamma irradiation or ultraviolet C irradiation. Consistent with deregulation in cell cycle control, persistent hyper-phosphorylation of the retinoblastoma protein and lack of a decrease in p34cdc2 were observed in irradiated cells. Furthermore, retinoblastoma protein remained hyperphosphorylated in control high passage confluent cultures that were serum starved for 72 h. Compared with low passage cells, the expression levels of the cyclin-dependent kinase inhibitor p27Kip1 were significantly reduced and the pattern of expression of the von Hippel-Lindau protein was aberrant. These data indicate that the process of cellular transformation of this xeroderma pigmentosum group C cell strain involves the progressive acquisition of mutations and abnormalities in the expression/function of several cell cycle regulators.
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Transformação Celular Neoplásica , Fibroblastos/citologia , Proteínas Nucleares , Pele/citologia , Ubiquitina-Proteína Ligases , Xeroderma Pigmentoso/fisiopatologia , Proteína Quinase CDC2/genética , Comunicação Celular , Proteínas de Ciclo Celular/genética , Células Cultivadas , Criança , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/genética , Humanos , Lactente , Ligases/genética , Masculino , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-mdm2 , Proteína do Retinoblastoma/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Proteína Supressora de Tumor Von Hippel-Lindau , Xeroderma Pigmentoso/patologiaRESUMO
Pluripotent or multipotent stem cells isolated from human embryos or adult central nervous system (CNS) may provide new neurons to ameliorate neural disorders. A major obstacle, however, is that the majority of such cells do not differentiate into neurons when grafted into non-neurogenic areas of the adult CNS. Here we report a new in vitro priming procedure that generates a nearly pure population of neurons from fetal human neural stem cells (hNSCs) transplanted into adult rat CNS. Furthermore, the grafted cells differentiated by acquiring a cholinergic phenotype in a region-specific manner. This technology may advance stem cell-based therapy to replace lost neurons in neural injury or neurodegenerative disorders.