AIM:To investigate the protective effect of lycopene on primary mouse cerebrocortical neurons ex -posed to tert-butyl hydroperoxide ( t-BHP) and its mechanisms of in vitro.METHODS:Primary cerebrocortical neurons of newborn C57 mice were extracted and divided into normal group , t-BHP group, lycopene +t-BHP group and lycopene group.The neuronal damage was induced by t-BHP exposure for 24 h, and the cell viability was examined by MTT assay . ROS content was measured by flow cytometry , and the protein levels of Bax , Bcl-2, caspase-3, cleaved caspase-3 and cyto-chrome C were examined by Western blot .RESULTS:The primary mouse cortical neurons expressed MAP-2 protein.Ly-copene at concentration of 4μmol/L reversed the decrease in cell viability .Flow cytometry revealed that lycopene treatment attenuated ROS content under the condition of t-BHP exposure.In addition, the protein level of Bcl-2 was increased, and the expression of Bax , cleaved caspase-3 and cytochrome-C was suppressed in lycopene +t-BHP group.CONCLUSION:The protective effect of lycopene on cortical neurons with t-BHP-induced injury may be involved in the mechanism of neuro-nal antioxidative response by down-regulating caspase-3 and Bax/Bcl-2 through the mitochondrial apoptotic pathway .

Objective: To analyze the clinicopathological characteristics and prognosis of diffuse midline glioma (DMG) with H3K27M mutation. Methods: Thirty cases of DMG were collected in Guangdong Sanjiu Brain Hospital from October 2016 to May 2018. The patients′ clinicopathological data including age, tumor site and histological grade, treatment and follow-up data were collected and analyzed. Results: There were 21 males and 9 females, with a mean age of 26 years (range 5-53 years). Fourteen tumors were located in thalamus, 12 in brainstem (one involved both thalamus and brainstem), and one each in hypothalamus, fourth ventricle, and sellar region, respectively. Two cases presented as diffuse intracranial lesions. Three cases (10.0%) were of WHO grade Ⅰ, 10 cases (33.3%) were grade Ⅱ, eight cases (26.7%) were grade Ⅲ, and nine cases (30.0%) were grade Ⅳ.All patients with gradeⅠ tumors were older than 20 years. Histologically, all were pilocytic astrocytoma-like. Immunohistochemical staining demonstrated that all tumors were IDH1 negative. Twenty-eight tumors showed diffuse expression of H3K27M, and two showed focal expression. Twenty-one tumors(100.0%, 21/21) showed absent expression of H3K27me3. Sixteen tumors (57.1%, 16/28) showed strongly positive expression of p53, and ATRX was negative in eight tumors (38.1%, 8/21). The Ki-67 proliferation index ranged from 5% to 40%. Eight cases (including two cases of H3K27M expression of individual cells) showed K27M mutation in H3F3A gene. Intracranial and spinal cord dissemination occurred in six cases (20.0%, 6/30). Median progression-free survival (PFS) was 9.5 months and median overall survival (OS) was 34 months. Mean PFS was 11.2 months and mean OS was 24.3 months. Compared with adults (>20 years old), children/adolescents (no more than 20 years old) had significantly shorter median OS (8 months vs. 34 months, P=0.013). There was no significant difference in PFS and OS between DMGs located in the brain stem/thalamus and other sites within midline (P>0.05). There was no significant difference in PFS and OS between WHO grade ⅠDMGs and WHO grade Ⅱ-Ⅳ DMGs (P>0.05). Conclusions DMGs occur more commonly in children and adolescents with male predominance. DMGs present with WHO Ⅰ-Ⅳ tumors morphologically, and pilocytic astrocytoma-like lesions with WHO Ⅰ are more common in adults. Expression of H3K27M but not H3K27me3 is helpful for diagnosis of DMG. The prognosis of children/adolescents is significantly worse than that of adults, whereas histological grade and tumor location do not affect prognosis.