Development of an m6A subtype classifier to guide precision therapy for patients with bladder cancer.

Purpose: Bladder cancer (BLCA) is a highly heterogeneous tumor. We aim to construct a classifier from the perspective of N6-methyladenosine methylation (m6A) to identify patients with different prognostic risks and treatment responsiveness for precision therapy. Methods: Data on gene expression profile, mutation, and clinical characteristics were mainly obtained from the TCGA-BLCA cohort. Unsupervised clustering was performed to construct m6A subtypes. The tumor microenvironment (TME) landscapes were explored by using ssGSEA, ESTIMATE, and MCPcounter algorithms. K-M survival curves and Cox regression analysis were used to demonstrate the significance of m6A subtypes in predicting prognosis. pRRophetic, oncoPredict, and TIDE algorithms were used to evaluate responsiveness to antitumor therapy. A classifier of m6a subtypes was finally developed based on random forest and artificial neural network (ANN). Results: The two m6A subtypes have significantly different m6A-related gene expression profiles and mutational landscapes. TME analysis showed a higher level of stromal and Inhibitory immune components in subtype B compared with subtype A. The m6A subtype is a clinically independent prognostic predictor of BLCA, subtype B has a poorer prognosis. Drug sensitivity analysis showed that subtype B has lower IC50 values and AUC values for cisplatin and docetaxel. Efficacy assessment showed significantly poorer radiotherapy efficacy and lower immunotherapy responsiveness in subtype B. We finally constructed an ANN classifier to accurately classify BLCA patients into two m6A subtypes. Conclusion: Our study developed a classifier for identifying subtypes with different m6A characteristics, and BLCA patients with different m6A subtypes have significantly different prognosis and responsiveness to antitumor therapy.

Comprehensive development and validation of gene signature for predicting survival in patients with glioblastoma.

Glioblastoma (GBM) is the most common brain tumor, with rapid proliferation and fatal invasiveness. Large-scale genetic and epigenetic profiling studies have identified targets among molecular subgroups, yet agents developed against these targets have failed in late clinical development. We obtained the genomic and clinical data of GBM patients from the Chinese Glioma Genome Atlas (CGGA) and performed the least absolute shrinkage and selection operator (LASSO) Cox analysis to establish a risk model incorporating 17 genes in the CGGA693 RNA-seq cohort. This risk model was successfully validated using the CGGA325 validation set. Based on Cox regression analysis, this risk model may be an independent indicator of clinical efficacy. We also developed a survival nomogram prediction model that combines the clinical features of OS. To determine the novel classification based on the risk model, we classified the patients into two clusters using ConsensusClusterPlus, and evaluated the tumor immune environment with ESTIMATE and CIBERSORT. We also constructed clinical traits-related and co-expression modules through WGCNA analysis. We identified eight genes (ANKRD20A4, CLOCK, CNTRL, ICA1, LARP4B, RASA2, RPS6, and SET) in the blue module and three genes (MSH2, ZBTB34, and DDX31) in the turquoise module. Based on the public website TCGA, two biomarkers were significantly associated with poorer OS. Finally, through GSCALite, we re-evaluated the prognostic value of the essential biomarkers and verified MSH2 as a hub biomarker.

Decorin alleviated chronic hydrocephalus via inhibiting TGF-ß1/Smad/CTGF pathway after subarachnoid hemorrhage in rats.

Chronic hydrocephalus is one of the severe complications after subarachnoid hemorrhage (SAH). However, there is no efficient treatment for the prevention of chronic hydrocephalus, partially due to poor understanding of underlying pathogenesis, subarachnoid fibrosis. Transforming growth factor-ß1(TGF-ß1) is a potent fibrogenic factor implicated in wide range of fibrotic diseases. To investigate whether decorin, a natural antagonist for TGF-ß1, protects against subarachnoid fibrosis and chronic hydrocephalus after SAH, two-hemorrhage-injection SAH model was conducted in 6-week-old rats. Recombinant human decorin(rhDecorin) (30ug/2ul) was administered before blood injection and on the 10th day after SAH. TGF-ß1, p-Smad2/3, connective tissue growth factor (CTGF), collagen I and pro-collagen I c-terminal propeptide were assessed via western blotting, enzyme-linked immunosorbent assay, radioimmunoassay and immunofluorescence. And neurobehavioral tests and Morris water maze were employed to evaluate long-term neurological functions after SAH. We found that SAH induced heightened activation of TGF-ß1/Smad/CTGF axis, presenting as a two peak response of TGF-ß1 in cerebrospinal fluid, elevation of TGF-ß1, p-Smad2/3, CTGF, collagen I in brain parenchyma and pro-collagen I c-terminal propeptide in cerebrospinal fluid, and increased lateral ventricle index. rhDecorin treatment effectively inhibited up-regulation of TGF-ß1, p-Smad2/3, CTGF, collagen I and pro-collagen I c-terminal propeptide after SAH. Moreover, rhDecorin treatment significantly reduced lateral ventricular index and incidence of chronic hydrocephalus after SAH. Importantly, rhDecorin improved neurocognitive deficits after SAH. In conclusion, rhDecorin suppresses extracellular matrix accumulation and following subarachnoid fibrosis via inhibiting TGF-ß1/Smad/CTGF pathway, preventing development of hydrocephalus and attenuating long-term neurocognitive defects after SAH.

Effect of social support and coping styles on the stress and mental health in relatives of patients with traumatic brain injury.

OBJECTIVE: To investigate the effect of social support and coping style on the stress and mental health in relatives of patients with traumatic brain injury. METHODS: The stress, mental health, social support and coping style were investigated in 300 relatives of patients with traumatic brain injury by Relative Stress Scale, Symptom Checklist-90, Social Support Rating Scale and Simplified Coping Style Questionnaire in Changsha City. RESULTS: The mental health problems in relatives of patients with traumatic brain injury were closely related to the levels of stress, the ways of coping and the social support. In addition to the direct eff ect of stress on mental health in relatives of patients, the ways of coping and social support functioned as a mediator in this regard. The value of mesomeric eff ect for coping styles and social support ranged from 23.6% to 43.0%, and social support had an advantage over the coping styles. CONCLUSION: Social support and coping styles should be considered in psychological nursing program to prevent and adjust the mental distress in relatives of patients with traumatic brain injury, which is beneficial to the treatment and recovery for patients.

[Effect of lavage with artificial cerebrospinal fluid on neural cell apoptosis and the ERK pathway after rat traumatic brain injury].

OBJECTIVE: To explore the eff ect of lavage with artificial cerebrospinal fluid on neural cell apoptosis and the extracellular regulated kinase (ERK) pathway aft er traumatic brain injury. METHODS: A total of 192 SD rats were randomly divided into a sham group, a traumatic brain injury model group, a local artificial cerebrospinal fluid group, and a local saline group. Each group was divided into 4 sub-groups by the sacrificed time at 6 h, 12 h, 1 d and 3 d aft er the operation. Th e phosphorylation of extracellular regulated kinase 2 (P-ERK2), TNF-α and cellular apoptosis were examined. RESULTS: Th e levels of P-ERK2 protein and TNF-α protein, as well as the number of apoptotic cells at each time point in the local artificial cerebrospinal fluid group were lower than those in the model group or in the saline group (P<0.05). CONCLUSION: Lavage with artificial cerebrospinal fluid can reduce apoptosis of neural cells after brain injury through the ERK pathway.

Sperm­associated antigen 9 promotes astrocytoma cell invasion through the upregulation of podocalyxin.

Podocalyxin (PODXL) has been found to increase the aggressive phenotype of a number of cancers, including astrocytoma. In addition, the progression of astrocytoma has been associated with sperm­associated antigen 9 (SPAG9), a recently characterized oncoprotein. In the present study, the association between SPAG9 and PODXL in human astrocytoma invasion and the underlying mechanisms were investigated for the first time, to the best of our knowledge. Overexpression and knockdown of SPAG9 were performed in SW1783 (grade III astrocytoma) and U87 (grade IV astrocytoma; glioblastoma) cells, respectively. PODXL expression at both the mRNA and the protein level, as well as the PODXL gene promoter activity, were significantly increased and decreased in parallel with the overexpression and knockdown of SPAG9 in astrocytoma cells; these effects were blocked by the selective c­Jun N­terminal kinase (JNK) inhibitor SP600125 (5 µM) and restored by the JNK agonist anisomycin (25 ng/ml), respectively. SPAG9 overexpression significantly increased cell invasion and matrix metalloproteinase­9 (MMP­9) expression in SW1783 cells, and this effect was reversed by knockdown of PODXL. In U87 cells, knockdown of SPAG9 markedly decreased cell invasion and MMP­9 expression, which was completely restored by overexpression of PODXL. In conclusion, it was demonstrated in the present study that SPAG9 upregulates PODXL expression in human astrocytoma cells at the PODXL gene promoter/transcriptional level through a JNK­dependent mechanism and that PODXL is a critical mediator of the promoting effect of SPAG9 on astrocytoma cell invasion, possibly through upregulation of MMP­9 expression. This study provides novel insights into the molecular mechanisms involved in astrocytoma invasion.

TFAM is directly regulated by miR-23b in glioma.

Mitochondrial transcription factor A (TFAM), a high-mobility group (HMG) protein, plays a central role in mitochondrial DNA (mtDNA) replication, transcription and inheritance. It has been shown that TFAM is associated with tumorigenesis. However, little is known regarding the posttranscriptional regulation of TFAM in glioma. In the present study, we found that the protein levels of TFAM were gradually increased, while the expression of miRNA-23b was gradually downregulated with the malignancy of glioma. Luciferase assay data demonstrated that miRNA-23b directly regulated TFAM. Furthermore, forced overexpression of miRNA-23b in U251 cells markedly inhibited the proliferation, cell cycle progression, migration and colony formation, while overexpression of TFAM significantly enhanced these biological processes. We further examined the related molecular mechanism, and found that the activity of the PI3K/Akt signaling pathway, critical for cell proliferation and migration, was suppressed in miRNA-23b-overexpressing U251 cells but was upregulated in TFAM-overexpressing cells. In addition, the expression levels of invasion-related MMP2 and MMP9 were decreased in miRNA-23b-overexpressing U251 cells but were increased in TFAM-overexpressing cells. Taken together, the present study provides a new regulatory mechanism as well as a promising therapy target for glioma.

[Effect of artificial cerebrospinal fluid lavage time on the edema of traumatic brain injury].

OBJECTIVE: To detect the impact of artificial cerebrospinal fluid lavage time on the edema of traumatic brain injury. METHODS: A total of 240 SD rats were randomly divided into a sham group, a traumatic brain injury model group, 3 artificial cerebrospinal fluid lavage groups (3 h, 6 h and 9 h). Each group was divided into 4 sub-groups by time of sacrifice namely 12 h, 1 d, 3 d and 7 d postoperatively. We detected the content of brain water, sodium, and potassium, and the VEGF expression to confirm whether the duration of lavage could reduce the traumatic brain edema. RESULTS: Compared with the sham group and the traumatic brain injury model group, brain water content and sodium content were decreased, while the potassium content and the VEGF levels were increased in the artificial cerebrospinal fluid lavage groups. Significant difference was found at 12 h, 1 d, and 3 d after the injury (P<0.05). With the increase of artificial cerebrospinal fluid lavage time, the difference was more obvious. CONCLUSION: Artificial cerebrospinal fluid lavage can reduce the brain edema after traumatic brain injury. The longer the lavage, the more obvious the effect.

[Expression of aquaporin-4 protein in rats with acute radiation-induced cerebral edema].

OBJECTIVE: To explore the relation between changes in expression of aquaporin-4(AQP4) protein and acute radiation-induced cerebral edema after Gamma knife radiation. METHODS: The experimental model was established in rats by radiating 2 mm right to median line in cerebral hemisphere with 50 Gy Gamma knife (the center located at the line of auditory canal). The changes of brain water content were measured by the wet and dry weight method. Immunohistochemistry was used to determine the change of expression of AQP4 protein at different periods after Gamma knife radiation. RESULTS: The brain water content and the expression of AQP4 in the target area and the peripheral zone obviously increased at 12 h after Gamma knife radiation, and achieved the peak after 2 d. It was still higher than normal after 14 d. The gray value of expression of aquaporin-4 was negatively related to brain water content (r=-0.9857, P<0.05). CONCLUSION: AQP4 has a close relationship with acute radiation-induced cerebral edema.