Inhibiting phosphatase and actin regulator 1 expression is neuroprotective in the context of traumatic brain injury.

Studies have found that the phosphatase actin regulatory factor 1 expression can be related to stroke, but it remains unclear whether changes in phosphatase actin regulatory factor 1 expression also play a role in traumatic brain injury. In this study we found that, in a mouse model of traumatic brain injury induced by controlled cortical impact, phosphatase actin regulatory factor 1 expression is increased in endothelial cells, neurons, astrocytes, and microglia. When we overexpressed phosphatase actin regulatory factor 1 by injection an adeno-associated virus vector into the contused area in the traumatic brain injury mice, the water content of the brain tissue increased. However, when phosphatase actin regulatory factor 1 was knocked down, the water content decreased. We also found that inhibiting phosphatase actin regulatory factor 1 expression regulated the nuclear factor kappa B signaling pathway, decreased blood-brain barrier permeability, reduced aquaporin 4 and intercellular adhesion molecule 1 expression, inhibited neuroinflammation, and neuronal apoptosis, thereby improving neurological function. The findings from this study indicate that phosphatase actin regulatory factor 1 may be a potential therapeutic target for traumatic brain injury.

DNA repair proteins as the targets for paroxetine to induce cytotoxicity in gastric cancer cell AGS.

To evaluate the potential anticancer effects of 1175 FDA-approved drugs, cell viability screening was performed using 25 human cancer cell lines covering 14 human cancer types. Here, we focus on the action of paroxetine, which demonstrated greater toxicity toward human gastric adenocarcinoma cell-line AGS cells compared with the other FDA-approved drugs, exhibiting an IC50 value lower than 10 µM. Evaluation of the underlying novel mechanisms revealed that paroxetine can enhance DNA damage in gastric cancer cells and involves downregulation of Rad51, HR23B and ERCC1 expression and function, as well as nucleotide shortage. Enhancement of autophagy counteracted paroxetine-induced apoptosis but did not affect paroxetine-induced DNA damage. Paroxetine also enhanced ROS generation in AGS cells, but a ROS scavenger did not improve paroxetine-mediated DNA damage, apoptosis, or autophagy, suggesting ROS might play a minor role in paroxetine-induced cell toxicity. In contrast, paroxetine did not enhance DNA damage, apoptosis, or autophagy in another insensitive gastric adenocarcinoma cell-line MKN-45 cells. Interestingly, co-administration of paroxetine with conventional anticancer agents sensitized MKN-45 cells to these agents: co-treated cells showed increased apoptosis relative to MKN-45 cells treated with the anticancer agent alone. Unequivocally, these data suggest that for the first time that paroxetine triggers cytotoxicity and DNA damage in AGS cells at least partly by reducing the gene expression of Rad51, HR23B, and ERCC1. Our findings also suggest that paroxetine is a promising candidate anticancer agent and/or chemosensitizing agent for use in combination with other anticancer drugs in cancer therapy. The molecular mechanisms underlying the anticancer activity of co-treatment with paroxetine and chemotherapy appear to be complex and are worthy of further investigation.

Urolithin A alleviates blood-brain barrier disruption and attenuates neuronal apoptosis following traumatic brain injury in mice.

Urolithin A (UA) is a natural metabolite produced from polyphenolics in foods such as pomegranates, berries, and nuts. UA is neuroprotective against Parkinson's disease, Alzheimer's disease, and cerebral hemorrhage. However, its effect against traumatic brain injury remains unknown. In this study, we established adult C57BL/6J mouse models of traumatic brain injury by controlled cortical impact and then intraperitoneally administered UA. We found that UA greatly reduced brain edema; increased the expression of tight junction proteins in injured cortex; increased the immunopositivity of two neuronal autophagy markers, microtubule-associated protein 1A/B light chain 3A/B (LC3) and p62; downregulated protein kinase B (Akt) and mammalian target of rapamycin (mTOR), two regulators of the phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR signaling pathway; decreased the phosphorylation levels of inhibitor of NFκB (IκB) kinase alpha (IKKα) and nuclear factor kappa B (NFκB), two regulators of the neuroinflammation-related Akt/IKK/NFκB signaling pathway; reduced blood-brain barrier permeability and neuronal apoptosis in injured cortex; and improved mouse neurological function. These findings suggest that UA may be a candidate drug for the treatment of traumatic brain injury, and its neuroprotective effects may be mediated by inhibition of the PI3K/Akt/mTOR and Akt/IKK/NFκB signaling pathways, thus reducing neuroinflammation and enhancing autophagy.

Repair of dural defects with electrospun bacterial cellulose membranes in a rabbit experimental model.

To evaluate the advantages and mechanisms involved in repairing rabbit dural defect with a novel electrospun bacterial cellulose (EBC) membrane, a series of experiments were carried out in vitro and in vivo. Compared with common bacterial cellulose (BC) membrane, a more dispersed and regular fiber structure and a better porosity and water holding capacity were found in the EBC membrane, which also had superior degradability. However, the biomechanical properties were slightly decreased. The results demonstrated that BC and EBC membranes had little effect on proliferation and apoptosis of mouse fibroblast cells. There were no complications such as infection, cerebrospinal fluid leakage, epilepsy and brain swelling after BC and EBC membrane repairs in rabbit models. Using real-time quantitative polymerase chain reaction (RT-qPCR) and western blot, the early inflammatory reactions in the EBC group were shown to be lower than in the BC group, and were close to the autologous dura mater group. Histological observations and western blot revealed more collagen fibers evenly distributed on the outer side of EBC membranes than in the BC and unpatched groups, and fewer brain tissue adhesions and epidural scars were found in the EBC group. Compared with common BC membrane, the EBC membrane had better biophysical properties and biocompatibility. It is expected to be a suitable alternative material for the repair of damaged dura mater.

Regulation of tNOX expression through the ROS-p53-POU3F2 axis contributes to cellular responses against oxaliplatin in human colon cancer cells.

BACKGROUND: Oxaliplatin belongs to the platinum-based drug family and has shown promise in treating cancer by binding to DNA to induce cytotoxicity. However, individual patients show diverse therapeutic responses toward oxaliplatin due to yet-unknown underlying mechanisms. We recently established that oxaliplatin also exert its anti-cancer activity in gastric cancer cell lines by targeting tumor-associated NADH oxidase (tNOX), attenuate NAD+ generation and reduce NAD+-dependent sirtuin 1 (SIRT1) deacetylase activity, which in turn enhances p53 acetylation and apoptosis. METHODS: In this study, differential cellular outcomes in response to oxaliplatin exposure of p53-wild-type versus p53-null HCT116 human colon cancer cells were examined. Cell growth profile was determined by cell impedance measurements and apoptosis was analyzed by flow cytometry. The engagement between oxaliplatin and tNOX protein was studied by cellular thermal shift assay. Furthermore, western blot analysis revealed that p53 was important in regulating tNOX expression in these cell lines. RESULTS: In p53-wild-type cells, we found that oxaliplatin inhibited cell growth by inducing apoptosis and concurrently down-regulating tNOX at both the transcriptional and translational levels. In p53-null cells, in contrast, oxaliplatin moderately up-regulated tNOX expression and yielded no apoptosis and much less cytotoxicity. Further experiments revealed that in p53-wild-type cells, oxaliplatin enhanced ROS generation and p53 transcriptional activation, leading to down-regulation of the transcriptional factor, POU3F2, which enhances the expression of tNOX. Moreover, the addition of a ROS scavenger reversed the p53 activation, POU3F2 down-regulation, and apoptosis induced by oxaliplatin in p53-wild-type cells. In the p53-null line, on the other hand, oxaliplatin treatment triggered less ROS generation and no p53 protein, such that POU3F2 and tNOX were not down-regulated and oxaliplatin-mediated cytotoxicity was attenuated. CONCLUSION: Our results show that oxaliplatin mediates differential cellular responses in colon cancer cells depending on their p53 status, and demonstrate that the ROS-p53 axis is important for regulating POU3F2 and its downstream target, tNOX. Notably, the depletion of tNOX sensitizes p53-null cells to both spontaneous and oxaliplatin-induced apoptosis. Our work thus clearly shows a scenario in which targeting of tNOX may be a potential strategy for cancer therapy in a p53-inactivated system.

Tumor-associated NADH oxidase (tNOX)-NAD+-sirtuin 1 axis contributes to oxaliplatin-induced apoptosis of gastric cancer cells.

Oxaliplatin belongs to the platinum-based drug family and has shown promise in cancer treatment. The major mechanism of action of platinum compounds is to form platinum-DNA adducts, leading to DNA damage and apoptosis. Accumulating evidence suggests that they might also target non-DNA molecules for their apoptotic activity. We explored the effects of oxaliplatin on a tumor-associated NADH oxidase (tNOX) in gastric cancer lines. In AGS cells, we found that the oxaliplatin-inhibited tNOX effectively attenuated the NAD+/NADH ratio and reduced the deacetylase activity of an NAD+-dependent sirtuin 1, thereby enhancing p53 acetylation and apoptosis. Similar results were also observed in tNOX-knockdown AGS cells. In the more aggressive MKN45 and TMK-1 lines, oxaliplatin did not inhibit tNOX, and induced only minimal apoptosis and cytotoxicity. However, the downregulation of either sirtuin 1 or tNOX sensitized TMK-1 cells to oxaliplatin-induced apoptosis. Moreover, tNOX-depletion in these resistant cells enhanced spontaneous apoptosis, reduced cyclin D expression and prolonged the cell cycle, resulting in diminished cancer cell growth. Together, our results demonstrate that oxaliplatin targets tNOX and SIRT1, and that the tNOX-NAD+-sirtuin 1 axis is essential for oxaliplatin-induced apoptosis.

Update on a tumor-associated NADH oxidase in gastric cancer cell growth.

Gastric cancer is one of the most common human malignancies, and its prevalence has been shown to be well-correlated with cancer-related deaths worldwide. Regrettably, the poor prognosis of this disease is mainly due to its late diagnosis at advanced stages after the cancer has already metastasized. Recent research has emphasized the identification of cancer biomarkers in the hope of diagnosing cancer early and designing targeted therapies to reverse cancer progression. One member of a family of growth-related nicotinamide adenine dinucleotide (NADH or hydroquinone) oxidases is tumor-associated NADH oxidase (tNOX; ENOX2). Unlike its counterpart CNOX (ENOX1), identified in normal rat liver plasma membranes and shown to be stimulated by growth factors and hormones, tNOX activity purified from rat hepatoma cells is constitutively active. Its activity is detectable in the sera of cancer patients but not in those of healthy volunteers, suggesting its clinical relevance. Interestingly, tNOX expression was shown to be present in an array of cancer cell lines. More importantly, inhibition of tNOX was well correlated with reduced cancer cell growth and induction of apoptosis. RNA interference targeting tNOX expression in cancer cells effectively restored non-cancerous phenotypes, further supporting the vital role of tNOX in cancer cells. Here, we review the regulatory role of tNOX in gastric cancer cell growth.

Clinicopathological correlation of keratinocyte growth factor and matrix metalloproteinase-9 expression in human gastric cancer.

AIMS AND BACKGROUND: Keratinocyte growth factor (KGF) is reported to be implicated in the growth of some cancer cells. Matrix metalloproteinase 9 (MMP-9) is thought to enhance the tumor invasion and metastasis ability. This study was aimed at analyzing the relationship between KGF and MMP-9 expression and patients' clinicopathological characteristics to clarify the clinical significance of the expression of KGF and MMP-9 in gastric cancer. METHODS: Tissue samples from 161 patients with primary gastric cancer were investigated using immunohistochemistry. The relationship between KGF and/or MMP-9 expression and clinicopathological characteristics was analyzed. RESULTS: KGF expression and MMP-9 expression in gastric cancer tissue were observed in 62 cases (38.5%) and 97 cases (60.2%), respectively. MMP-9 was significantly associated with depth of invasion, lymph node metastasis and TNM stage. The prognosis of MMP-9-positive patients was significantly poorer than that of MMP-9-negative patients (p = 0.009). KGF expression was positively correlated with MMP-9 expression in gastric cancer, and the prognosis of patients with both KGF- and MMP-9-positive tumors was significantly worse than that of patients with negative tumors for either factor (p = 0.045). Expression of MMP-9 was revealed to be an independent prognostic factor (p = 0.026). CONCLUSIONS: Coexpression of KGF and MMP-9 in gastric cancer could be a useful prognostic factor, and MMP-9 might also serve as a novel target for both prognostic prediction and therapeutics.

Endostatin/collagen XVIII is increased in cerebrospinal fluid after severe traumatic brain injury.

Recent studies have suggested that endogenous angiogenesis inhibitor endostatin/collagen XVIII might play an important role in the secondary brain injury following traumatic brain injury (TBI). In this study, we measured endostatin/collagen XVIII concentrations serially for 1 week after hospitalization by using the enzyme-linked immunosorbent assay method in the cerebrospinal fluid (CSF) of 30 patients with TBI and a Glasgow Coma Scale (GCS) score of 8 or less on admission. There was a significant trend toward increased CSF levels of endostatin after TBI versus control from 72 h after injury. In patients with GCS score of 3-5, CSF endostatin concentration was substantially higher at 72 h after injury than that in patients with GCS score of 6-8 (P < 0.05) and peaked rapidly at day 5 after injury, but decreased thereafter. The CSF endostatin concentration in 12 patients with an unfavorable outcome was significantly higher than that in 18 patients with a favorable outcome at day 5 (P = 0.043) and day 7 (P = 0.005) after trauma. Receiver operating characteristic curve analysis suggested a reliable operating point for the 7-day CSF endostatin concentration predicting poor prognosis to be 67.29 pg/mL. Our preliminary findings provide new evidence that endostatin/collagen XVIII concentration in the CSF increases substantially in patients with sTBI. Its dynamic change may have some clinical significance on the judgment of brain injury severity and the assessment of prognosis. This trial is registered with the ClinicalTrials.gov Identifier: NCT01846546.

Dose-dependent protective effect of bisperoxovanadium against acute cerebral ischemia in a rat model of ischemia/reperfusion injury.

PTEN (phosphatase and tensin homologue deleted on chromosome 10) is a dual-specificity lipid and protein phosphatase. The loss of PTEN was originally discovered in numerous human cancers. PTEN inhibition by bisperoxovanadium (bpV) reduces neurological damage after ischemic brain injury. The purpose of this study was to identify the optimal neuroprotective dose of bpV when administrated after focal ischemia/reperfusion (I/R) injury in rats. Focal I/R injury was induced using the middle cerebral artery occlusion method. bpV at doses of 0.25, 0.50 and 1.0 mg/kg were injected intraperitoneally just after reperfusion, with saline serving as a vehicle control. A maximal reduction in brain injury was observed with 1.0 mg/kg bpV. This dose of bpV also significantly blocked apoptosis in the penumbral cortex of rats. This beneficial effect was associated with the increasing levels of Akt phosphorylation in the penumbral cortex. These results demonstrate that the pharmacological inhibition of PTEN protects against I/R injury in a dose-dependent manner and the protective effect might be induced through upregulation of the phosphoinositide-3 kinase/Akt pro-survival pathway, suggesting a new therapeutic strategy to combat ischemic brain injury.

Predicting outcomes after traumatic brain injury: the development and validation of prognostic models based on admission characteristics.

BACKGROUND: Early estimation of prognosis for the patient with traumatic brain injury is an important factor in making treatment decisions, resource allocation, classify patients, or communicating with family. We aimed to develop and validate practical prognostic models for mortality at 30 days and for 6 months unfavorable outcome after moderate and severe traumatic brain injury. METHODS: Retrospectively collected data from our department were used to develop prognostic models for outcome. We developed four prognostic models based on admission predictors with logistic regression analysis. The performance of models was assessed with respect to discrimination and calibration. Discriminative ability was evaluated with C statistic, equal to the area under the receiver operating characteristic curve. Calibrative ability was assessed with the Hosmer-Lemeshow test (H-L test). The internal validity of models was evaluated with the bootstrap re-sampling technique. We validated three of the models in an external series of 203 patients that collected from another research center. Discrimination and calibration were further assessed to indicate the performance of the models in external patients. RESULTS: Logistic regression showed that age, pupillary reactivity, motor Glasgow Coma Score, computed tomography characters, glucose, hemoglobin, D-dimer, serum calcium, and intracranial pressure were independent prognostic factors of outcome. The models discriminated well in the development patients (C statistic 0.709-0.939). We extensively validate three of the models. Internal validation showed no overoptimism in any of the models' predictive C statistics. External validity was much better (C statistic 0.844-0.902). Calibration was also good (H-L tests, p > 0.05). Computer-based calculator that based on prognostic models was developed for clinical use. CONCLUSION: Our validated prognostic models have good performance and are generalizable to be used to predict outcome of new patients. We recommend the use of prognostic models to complement clinical decision making.

[Anatomic study of mandibular bone flap pedicled with temporal muscle for midface bone defect].

OBJECTIVE: To study the anatomy of mandibular bone flap pedicled with temporal muscle for midfacial bone defects. METHODS: The shape and blood supply of the temporal muscle and mandibular ramus, as well as their relationship, were observed and measured in 30 sides of adult head specimens. RESULTS: The temporal muscle has a fan-shaped main portion, then is scattered into three bundles as anterolateral, anteromedial, posterior bundles, which end respectively at anterior border of ramus, the temporal ridge and posterior portion of coronoid process. Then the muscle goes downward until it reaches the distal side of the third medial surface molar and attaches the 3/4 of medial surface of anterior portion of ramus. The blood supply of temporal muscle includes the medial temporal artery with external diameter of (0.76 +/- 0.20) mm, the anterior deep temporal arteries with external diameter of (0.79 +/- 0.21) mm, posterior deep temporal arteries with external diameter of (0.98 +/- 0.64) mm, the accessory deep temporal artery formed by many little branches. The anterior part of ramus is supplied by the periosteal arteries and the bony perforator of the deep temporal arteries. Rectangular ramus of mandible was divided into anterior portion and posterior portion by the line linking the lowest point of mandibular notch, mandibular foramen and mandibular canal. Anterior portion can supply a bone flap with a size of (46.67 +/- 6.85) mm x (17.98 +/- 2.64) mm x (11.49 +/- 0.99) mm. CONCLUSIONS: The mandibular bone flap pedicled with temporal muscle has a reliable blood supply and abundant bone volume. It is feasible to design a mandibular bone flap pedicled with temporal muscle for midfacial bone defect.

Glial implications in transplantation therapy of spinal cord injury.

Spinal cord injuries are damages that result in complete or partial loss of sensation and/or mobility and affect the life qualities of many patients. Their pathophysiology includes primary and secondary processes, which are related with the activation of astrocytes and microgliacytes and the degeneration of oligodendrocytes. Although transplantation of embryonic stem cells or neural progenitor cells is an attractive strategy for repair of the injured central nervous system (CNS), transplantation of these cells alone for acute spinal cord injuries has not resulted in robust axon regeneration beyond the injury sites. This may be due to the progenitor cells differentiating to the cell types that support axon growth poorly and/or their inability to modify the inhibitory environment of adult CNS after injury. Recent studies indicate that transplantation of glial progenitor cells has exhibited beneficial effects on the recovery and promising future for the therapy strategy of spinal cord injury. In this review, we summarized the data from recent literature regarding glial implications in transplantation therapy of spinal cord injury.

Risk factors related to hospital mortality in patients with isolated traumatic acute subdural haematoma: analysis of 308 patients undergone surgery.

BACKGROUND: Acute subdural haematoma (ASDH) is a common traumatic brain injury with a relatively high mortality rate. However, few studies have examined the factors predicting the outcome of isolated traumatic ASDH. This clinical study examined the hospital mortality and analyzed the risk factors for mortality in patients treated surgically for isolated traumatic ASDH. METHODS: We collected 308 consecutive patients who underwent neurosurgery for isolated traumatic ASDH between January 1999 and December 2007 and used multivariate Logistic regression analysis to evaluate the influence of 11 clinical variables on hospital mortality. RESULTS: The overall hospital mortality was 21.75% (67/308). Age (OR = 1.807), preoperative Glasgow Coma Score (OR = 0.316), brain herniation (OR = 2.181) and the time from trauma to decompression (OR = 1.815) were independent predictors of death, while no independent association was observed between hospital mortality and haematoma volume, midline shift, acute brain swelling or brain herniation duration, although these variables were correlated with hospital mortality in univariate analyses. CONCLUSIONS: This study identified the risk factors for hospital mortality in patients who underwent surgical treatment for isolated traumatic ASDH. An increased risk of death occurs in patients who are over 50 years of age and have lower preoperative Glasgow Coma Scores, the presence of brain herniation and a long interval between trauma and decompression. The findings should help clinicians determine management criteria and improve survival.

Clinicopathologic correlation of up-regulated genes identified using cDNA microarray and real-time reverse transcription-PCR in human colorectal cancer.

PURPOSE: We hypothesize that changes in the transcription of up-regulated genes are biologically meaningful and may be linked to variations in tumor behavior and clinical features. This study aimed to find individual up-regulated genes responsible for clinicopathologic variations in human colorectal cancer. EXPERIMENTAL DESIGN: Genes up-regulated concurrently in four microarray experiments were taken as candidate genes; 20 candidate genes were verified using real-time reverse transcription-PCR in these four experiments, along with 27 new samples. The presence or absence of up-regulation of these genes was correlated with 10 clinicopathologic variables from 31 patients. The mRNA transcript levels of these 20 candidate genes in the 31 paired samples were also correlated with each other to disclose any expression relationship. RESULTS: Forty percent (8/20) of the candidate genes were verified by real-time reverse transcription-PCR to have a tumor/normal expression ratio > 2. Up-regulation of THY1 and PHLAD1 was associated with the presence of anemia in colon cancer patients (P = 0.036 and 0.009, respectively). Up-regulation of HNRPA1 was more significant in cancer growing in the right-sided colon than the left side (P = 0.027). Up-regulated GPX2 was related to a higher degree of tumor differentiation (P = 0.019). c-MYC was significantly over-expressed in specimens from male compared with female colon cancer patients (P = 0.012). GRO1 was significantly up-regulated in patients younger than 65 years old (P = 0.010) and was found to be frequently over-expressed when cancers were less invasive. In addition, we found that normalized transcript levels of HNRPA1 were tightly associated with that of c-MYC (r = 0.948). CONCLUSIONS: Validation of microarray data using another independent laboratory approach is mandatory and statistical correlation between gene expression status and the patient's clinical features may reveal individual genes relevant to tumor behavior and clinicopathologic variations in human colorectal cancer.