Effects of over-expression of E2F transcription factor 1 on radiosensitivity glioma U251 cells / 中华行为医学与脑科学杂志

Objective:To investigate the effects of over-expression of E2F transcription factor 1 (E2F1) on proliferation, invasion, apoptosis and radiosensitivity of glioma cell U251.Methods:Real-time quantitative PCR (qRT-PCR) were used to detect the differential expression of E2F1 mRNA in glioma cells LN18, SW1088, U251 and normal brain glial cells. The stable over-expression of E2F1 plasmid was constructed and transfected into U251 cells. qRT-PCR and Western blot test were used to detect the expression of E2F1, pituitary tumor transforming gene 1(PTTG1), C-Myc, B-cell lymphoma-2 (Bcl-2), Bcl2-associated X (Bax) mRNA and protein expression in the control group and E2F1 over-expression group.U251 cells were divided into control group(no X-ray irradiation), irradiation group(6 Gy dose of X-ray), and irradiation + E2F1 over-expression group(transfected with E2F1 first, then irradiated by 6 Gy of X-ray). Cell proliferation ability was detected by cell counting Kit-8(CCK-8) cell viability detection reagent, and cell invasion and migration ability were detected by Transwell chamber. Apoptosis and cell cycle were detected by flow cytometry.GraphPad Prism 8.0 was used for data analysis.The statistical methods were one-way ANOVA and independent sample t-test. Results:qRT-PCR showed that there was statistical difference in the mRNA levels of E2F1( F=201.92, P<0.05) in different cell lines.The expression levels of E2F1 mRNA in LN18(4.04±0.29), SW1088(3.19±0.16)and U251(4.66±0.20) cells were higher than those in HEB(1.02±0.07)cells ( q=27.00, 19.40, 32.52, all P<0.05). After successfully constructing U251 cells with stable over-expression of E2F1 plasmid, qRT-PCR and Western blot detection results showed that: the mRNA and protein levels of E2F1, PTTG1, C-Myc and Bcl-2 in E2F1 over-expression group were higher than those in control group ( t=77.16, 57.88, 4.63, 51.13, 7.50, 70.85, 8.38, 48.81, all P<0.05). Bax mRNA(0.20±0.01) and protein(0.66±0.01) levels were lower than those in control group((1.00±0.02), (0.94±0.01)), and the differences were statistically significant ( t=1.74, 54.65, both P<0.05). After X-ray irradiation (6 Gy), CCK8 detection results showed: the proliferation ability of the three groups at 24, 48, 72 and 96 h were significantly different ( F=95.41, 187.53, 1 158.49, 7 883.78, all P<0.05). The proliferation capacity of the irradiation group were lower than those of the control group at 24, 48, 72 and 96 h ( q=19.51, 27.20, 66.60, 174.9, all P<0.05). The proliferation capacity of irradiation + E2F1 over-expression group at 24, 48, 72 and 96 h were higher than those of irradiation group ( q=10.63, 10.81, 21.11, 60.90, all P<0.05). Transwell assay results showed that there were significant differences in cell invasion and migration ability among the three groups ( F=315.38, 681.10, both P<0.05). The invasion and migration ability of cells in the irradiation group were lower than those in the control group ( q=35.09, 12.76, both P<0.05), and the invasion and migration ability of cells in the irradiation + E2F1 over-expression group were higher than those in the irradiation group ( q=52.06, 22.81, both P<0.05). Flow cytometry showed that there were significant differences in apoptosis rate and percentage of cells in each cycle among the three groups ( F=667.63, 3 213.30, 3 011.26, 861.98, all P<0.05). The percentage of the apoptosis rate, S phase and G2 phase cells in the irradiation group were higher than those in the control group ( q=51.10, 89.39, 51.82, all P<0.05), while the percentage of G1 phase cells in the irradiation group was lower than that in the control group ( q=141.2, P<0.05). The apoptosis rate and percentage of S phase and G2 phase cells in the irradiation + E2F1 over-expression group were lower than those in the irradiation group ( q=18.87, 41.42, 29.31, all P<0.05), while the number of G1 phase cells in the irradiation + E2F1 over-expression group was lower than that in the irradiation group ( q=70.73, P<0.05). Conclusion:Over-expression of E2F1 can reduce the radiosensitivity of glioma U251 cells by regulating the expression of mRNA and protein of genes related to cell cycle and apoptosis, and E2F1 may be involved in the radioresistance of glioma cells.

Research Progress of Diagnosis and Treatment of Glioblastoma / 肿瘤防治研究

Glioblastoma is the most common primary malignant brain tumor. Despite large-scale researches have been carried out, the prognosis of glioblastoma is still not significantly improved. In recent years, with the application of multi-omics studies in glioblastoma, the understanding of glioblastoma has been deepened. The classification of glioblastoma has been revised; moreover, new therapeutic methods such as targeted therapy, immunotherapy and tumor treating fields have been developed on the basis of the standard therapy. This article reviews the recent progress in the diagnosis and treatment of glioblastoma.

Mining prognostic marker of glioma based on weighted gene co-expression network analysis / 中国医师杂志

Objective:To identify effective biomarkers for glioma patients.Methods:The mRNA expression profiles of 464 glioma patients with complete clinical follow-up information were downloaded from the Chinese Glioma Genome Atlas (CGGA). Weighted gene co-expression network analysis (WGCNA) was used to identify gene modules related to World Health Organization (WHO) grading of glioma, and univariate and multivatiate Cox regression analysis were performed to identify gliomas survival-related genes.Results:In weighted gene co-expression analysis, the module Brown was significantly positively correlated with glioma WHO stage ( r=0.55, P<0.05). In univariate analysis, five genes (TAGLN2, IGFBP2, METTL7B, ARAP3, PLAT) that were most significantly associated with clinical prognosis were selected for multivariate survival analysis, and the prognosis model was established to calculate the risk score. The receiver operating characteristic curve (ROC) confirmed that the risk score had high accuracy in predicting the 1-, 3-, 5-year survival rate of glioma patients. The above survival analysis results were verified in the Cancer Genome Atlas (TCGA) database. Conclusions:We use mRNA expression profiles to establish prognostic markers for gliomas to assess the overall survival of patients with glioma.

LRIG1 Enhances Chemosensitivity by Modulating BCL-2 Expression and Receptor Tyrosine Kinase Signaling in Glioma Cells

PURPOSE: Leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) are an inhibitor of receptor tyrosine kinases (RTKs) that was discovered in recent years, and many studies showed that LRIG1 is a tumor suppressor gene and may be related to tumor drug resistance. In this study, we explored whether LRIG1 protein expression can improve the chemosensitivity of glioma cells and what was its mechanism. MATERIALS AND METHODS: We collected 93 cases of glioma tissues and detected the expression of LRIG1 and BCL-2. We constructed a multidrug resistance cell line U251/multidrug resistance (MDR) and examined the change of LRIG1 and BCL-2 at mRNA and protein expression levels. LRIG1 expression was upregulated in U251/MDR cells and we detected the change of multidrug resistance. Meanwhile, we changed the expression of LRIG1 and BCL-2 and explored the relationship between LRIG1 and BCL-2. Finally, we also explored the relationship between LRIG1 and RTKs. RESULTS: LRIG1 was negatively correlated with BCL-2 expression in glioma tissue and U251/MDR cells, and upregulation of LRIG1 can enhance chemosensitivity and inhibit BCL-2 expression. Furthermore, LRIG1 was negatively correlated with RTKs in U251/MDR cells. CONCLUSION: These results demonstrated that LRIG1 can improve chemosensitivity by modulating BCL-2 expression and RTK signaling in glioma cells.

Clinical features and removal strategies of intracranial foreign bodies / 中华创伤杂志

Objective To investigate clinical features,diagnosis,clearance strategies and prognosis of intracranial foreign bodies.Methods Twenty patients with intracranial foreign bodies were analyzed retrospectively,together with review of the related literatures.Results Twenty patients underwent craniotomy for intracranial foreign body removal under guidance of preoperative CT and X-ray localizations and intraoperative C-arm X-ray machine and ultrasound localizations.A total of 35 foreign bodies were removed.One patient underwent second surgical resection after the incomplete removal due to displacement of intracranial foreign bodies.According to Glasgow outcome score (GOS) at discharge,the outcomes were good (GOS =4-5 points) in 16 patients,poor (GOS =2-3 points) in three and death (GOS =1 point) in one.Conclusions CT and X-ray locations before surgery and C-ann X-ray machine and ultrasound locations in operation avail the removal of foreign bodies by craniotomy.In the meantime,prognosis is satisfactory.

Glioma Stem Cell-Targeted Dendritic Cells as a Tumor Vaccine Against Malignant Glioma

PURPOSE: Cancer stem cells have recently been thought to be closely related to tumor development and reoccurrence. It may be a promising way to cure malignant glioma by using glioma stem cell-targeted dendritic cells as a tumor vaccine. In this study, we explored whether pulsing dendritic cells with antigens of glioma stem cells was a potent way to induce specific cytotoxic T lymphocytes and anti-tumor immunity. MATERIALS AND METHODS: Cancer stem cells were cultured from glioma cell line U251. Lysate of glioma stem cells was obtained by the repeated freezing and thawing method. Dendritic cells (DCs) were induced and cultured from the murine bone marrow cells, the biological characteristics were detected by electron microscope and flow cytometry. The DC vaccine was obtained by mixing DCs with lysate of glioma stem cells. The DC vaccine was charactirizated through the mixed lymphocyte responses and cell killing experiment in vitro. Level of interferon-gamma (IFN-gamma) in the supernatant was checked by ELISA. RESULTS: After stimulation of lysate of glioma stem cell, expression of surface molecules of DC was up-regulated, including CD80, CD86, CD11C and MHC-II. DCs pulsed with lysate of glioma stem cells were more effective than the control group in stimulating original glioma cells-specific cytotoxic T lymphocytes responses, killing glioma cells and boosting the secretion of IFN-gamma in vitro. CONCLUSION: The results demonstrated DCs loaded with antigens derived from glioma stem cells can effectively stimulate naive T cells to form specific cytotoxic T cells, kill glioma cells cultured in vitro.

Transphenoidal-upslope approach by lateral rhinotomy to chordoma invading the sphenoid bone and clivus / 临床耳鼻咽喉头颈外科杂志

This paper reported one patient who was treated through transphenoidal-upslope approach by lateral rhinotomy and the tumor was successfully removed. The patient was male of 38 years old. He suffered intermittent headache with blurred vision and left eye outreach disorder for more than a year. The visual inspection showed there was dark area of the left eye lateral. CT showed slopes density placeholder and bone window showed the slope of bone quality had been severely damaged. MRI showed T1 image slopes parts and other low signal placeholder forward to invade the sphenoid sinus. In addition, there was undermine the slope bone and brain stem boundaries clearly and T2 images showed high-signal, inhomogeneous enhancement. We found during the operation that the slope was partially destroyed and part of the tumor was prominent to the pharynx tumor. The pathologic examination confirmed that it is chordoma.

The Causes and Treatment for Cerebrospinal Fluid Leak after Microsurgical Removal of Vestibular Schwannomas / 中国医师杂志

Objective To explore the causes and treatment for cerebrospinal fluid(CSF) leak after microsurgical removal of vestibular schwannomas(VS) with the suboccipital retrosigmoid approach.Methods A retrospective study was accomplished on 258 patients with VS operated through the suboccipital retrosigmoidal approach from Jan 1994 to Aug 2003.After operation,cerebrospinal fluid rhinorrhea occurred in 19 cases and subcutaneous retroauricular CSF leak occurred in 5 cases.Results In 14 cases the CSF leak was stopped after treatment by external lumbar cerebrospinal fluid drainage(CELCFD).Six patients were operated again with sealing the internal acoustic meatus and the mastoid cells with fibrin glue and muscle.The patients were followed up for 14 months to 8 years after treatment,and there was no recurrence of CSF leak or delayed onset meningitis.Conclusion CSF leak was the common complication after vestibular schwannoma removal and the most common reason was the drilled posterior wall of the internal acoustic meatus with opening of the mastoid cells.The closure of petrous air cells was very important to prevent its postoperative CSF leak.Most of the patients were successfully treated by external lumbar cerebrospinal fluid drainage and only a few cases needed revision surgery.