Development and validation of a prognostic nomogram model in primary cutaneous and subcutaneous soft tissue angiosarcoma.

OBJECTIVE: The current study aimed to investigate the prognosis and treatment of primary cutaneous angiosarcoma (PCA) and primary subcutaneous angiosarcoma (PSCA), and tried to develop a prognostic nomogram model of them. METHODS: A total of 1763 cases retrieved from the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively analyzed. Survival analyses were performed to explore the prognosis of patients and the effects of different treatment methods. All data were randomly allocated into a training set and a testing set to develop and validate the nomogram model. RESULTS: The findings showed that age, sex, grade, tumor size, multiple primary malignant tumors, stage, primary site surgery (PSS), radiotherapy (RT), and chemotherapy (CT) were correlated with prognosis (p < .05). The nomogram achieved good accuracy in predicting the prognosis. PSS + RT + CT showed the best prognosis for patients in stages I, II, and III (p < .05). CONCLUSION: PCA and PSCA are rare with poor prognoses. Patients undergoing PSS may not gain survival benefits from combining with RT or (and) CT, whereas PSS + RT + CT should be actively performed in earlier stages to improve the prognosis of patients. The nomogram model can be used to predict the overall survival rate and guide better treatment.

Single Hormone Receptor-Positive Metaplastic Breast Cancer: Similar Outcome as Triple-Negative Subtype.

Background: Metaplastic breast cancer (MBC) is a rare and aggressive subtype of the breast. To understand the characteristics and prognosis of single hormone receptor-positive (HR+) MBC (estrogen receptor-positive [ER+]/progesterone receptor-negative [PR-] and ER-/PR+), we compared these tumors to double HR+ tumors as well as HR- tumors. Patients and Methods: The Surveillance, Epidemiology, and End Results database was used to analyze MBC between 1975 and 2016. The effect of HR status was evaluated using a multivariate Cox regression model. Results: We included 3369 patients with a median follow-up time of 42 months (range 0-322 months). In this study, 280 (8.3%) cases were double HR+ tumors, 2597 (77.1%) were double HR- tumors, and 492 (14.6%) cases were single HR+ tumors, of which 159 (4.7%) cases were ER-/PR+ tumors and 333 (9.9%) were ER+/PR- tumors. On multivariate Cox analysis, the prognosis was related to age, race/ethnicity, tumor grade, TNM stage, and surgery. HR status remained no impact on breast cancer-specific survival (BCSS). In the Kaplan-Meier curve, HR status was not associated with better BCSS or overall survival (OS). In patients without HER2 overexpression, the BCSS and OS of ER+/PR- and ER-/PR+ tumors were not significantly different from that of ER-/PR- and ER+/PR+ tumors. The difference remains no significant in patients with HER2 overexpression. Conclusions: In comparison with both ER-/PR- and ER+/PR+ tumors, we have identified clinically and biologically distinct features of single HR+ tumors. In patients with or without HER2 overexpression, the prognosis of single HR+ tumors was similar to ER-/PR- and ER+/PR+ tumors.

Intranasal Insulin Prevents Anesthesia-induced Cognitive Impairments in Aged Mice.

BACKGROUND: Preclinical and clinical evidence suggests that elderly individuals are at increased risk of cognitive decline after general anesthesia. General anesthesia is also believed to be a risk factor for Postoperative Cognitive Dysfunction (POCD) and Alzheimer's Disease (AD). Intranasal administration of insulin, which delivers the drug directly into the brain, improves memory and cognition in both animal studies and small clinical trials. However, how insulin treatment improves cognitive function is poorly understood. METHODS: Aged mice were pretreated with intranasal insulin or saline before anesthesia. Propofol was added intraperitoneally to the mice from 7th day of insulin/saline treatment, and general anesthesia was induced and maintained for 2 hours/day for 5 consecutive days. Mice were evaluated at 26th day when the mice were continued on insulin or saline administration for another 15 days. RESULTS: We found that intranasal insulin treatment prevented anesthesia-induced cognitive impairments, as measured by novel object recognition test and contextual-dependent fear conditioning test. Insulin treatment also increased the expression level of Post-synaptic Density Protein 95 (PSD95), as well as upregulated Microtubule-associated Protein-2 (MAP-2) in the dentate gyrus of the hippocampus. Furthermore, we found that insulin treatment restored insulin signaling disturbed by anesthesia via activating PI3K/PDK1/AKT pathway, and attenuated anesthesia-induced hyperphosphorylation of tau at multiple AD-associated sites. We found the attenuation of tau hyperphosphorylation occurred by increasing the level of GSK3ß phosphorylated at Ser9, which leads to inactivation of GSK-3ß. CONCLUSION: Intranasal insulin administration might be a promising therapy to prevent anesthesiainduced cognitive deficit in elderly individuals.

Intranasal insulin prevents anesthesia-induced hyperphosphorylation of tau in 3xTg-AD mice.

BACKGROUND: It is well documented that elderly individuals are at increased risk of cognitive decline after anesthesia. General anesthesia is believed to be a risk factor for Alzheimer's disease (AD). Recent studies suggest that anesthesia may increase the risk for cognitive decline and AD through promoting abnormal hyperphosphorylation of tau, which is crucial to neurodegeneration seen in AD. METHODS: We treated 3xTg-AD mice, a commonly used transgenic mouse model of AD, with daily intranasal administration of insulin (1.75 U/day) for one week. The insulin- and control-treated mice were then anesthetized with single intraperitoneal injection of propofol (250 mg/kg body weight). Tau phosphorylation and tau protein kinases and phosphatases in the brains of mice 30 min and 2 h after propofol injection were then investigated by using Western blots and immunohistochemistry. RESULTS: Propofol strongly promoted hyperphosphorylation of tau at several AD-related phosphorylation sites. Intranasal administration of insulin attenuated propofol-induced hyperphosphorylation of tau, promoted brain insulin signaling, and led to up-regulation of protein phosphatase 2A, a major tau phosphatase in the brain. Intranasal insulin also resulted in down-regulation of several tau protein kinases, including cyclin-dependent protein kinase 5, calcium/calmodulin-dependent protein kinase II, and c-Jun N-terminal kinase. CONCLUSION: Our results demonstrate that pretreatment with intranasal insulin prevents AD-like tau hyperphosphorylation. These findings provide the first evidence supporting that intranasal insulin administration might be used for the prevention of anesthesia-induced cognitive decline and increased risk for AD and dementia.

Intranasal insulin restores insulin signaling, increases synaptic proteins, and reduces Aß level and microglia activation in the brains of 3xTg-AD mice.

Decreased brain insulin signaling has been found recently in Alzheimer's disease (AD). Intranasal administration of insulin, which delivers the drug directly into the brain, improves memory and cognition in both animal studies and small clinical trials. However, the underlying mechanisms are unknown. Here, we treated 9-month-old 3xTg-AD mice, a commonly used mouse model of AD, with daily intranasal administration of insulin for seven days and then studied brain abnormalities of the mice biochemically and immunohistochemically. We found that intranasal insulin restored insulin signaling, increased the levels of synaptic proteins, and reduced Aß40 level and microglia activation in the brains of 3xTg-AD mice. However, this treatment did not affect the levels of glucose transporters and O-GlcNAcylation or tau phosphorylation. Our findings provide a mechanistic insight into the beneficial effects of intranasal insulin treatment and support continuous clinical trials of intranasal insulin for the treatment of AD.

Temperature control can abolish anesthesia-induced tau hyperphosphorylation and partly reverse anesthesia-induced cognitive impairment in old mice.

AIMS: Anesthesia is related to cognitive impairment and the risk for Alzheimer's disease. Hypothermia during anesthesia can lead to abnormal hyperphosphorylation of tau, which has been speculated to be involved in anesthesia-induced cognitive impairment. The aim of this study was to investigate whether maintenance of the tau phosphorylation level by body temperature control during anesthesia could reverse the cognitive dysfunction in C57BL/6 mice. METHODS: Eighteen-month-old mice were repeatedly anesthetized during a 2-week period with or without maintenance of body temperature, control mice were treated with normal saline instead of anesthetics. Tau phosphorylation level in mice brain was detected on western blot, and cognitive performance was measured using the Morris water maze (MWM). RESULTS: After anesthesia-induced hypothermia in old mice, tau was hyperphosphorylated and the cognitive performance, measured on MWM, was impaired. When body temperature was controlled during anesthesia, however, the tau hyperphosphorylation was completely avoided, and there was partial recovery in cognitive impairment measured on the MWM. CONCLUSION: Hyperphosphorylation of tau in the brain after anesthesia is an important event, and it might be, although not solely, responsible for postoperative cognitive decline.

Rapamycin decreases tau phosphorylation at Ser214 through regulation of cAMP-dependent kinase.

Preventing or reducing tau hyperphosphorylation is considered to be a therapeutic strategy in the treatment of Alzheimer's disease (AD). Rapamycin may be a potential therapeutic agent for AD, because the rapamycin-induced autophagy may enhance the clearance of the hyperphosphorylated tau. However, recent rodent studies show that the protective effect of rapamycin may not be limited in the autophagic clearance of the hyperphosphorylated tau. Because some tau-related kinases are targets of the mammalian target of rapamycin (mTOR), we assume that rapamycin may regulate tau phosphorylation by regulating these kinases. Our results showed that in human neuroblastoma SH-SY5Y cells, treatment with rapamycin induced phosphorylation of the type IIα regulatory (RIIα) subunit of cAMP-dependent kinase (PKA). Rapamycin also induced nuclear translocation of the catalytic subunits (Cat) of PKA and decreases in tau phosphorylation at Ser214 (pS214). The above effects of rapamycin were prevented by pretreatment with the mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) inhibitor U0126. In addition, these effects of rapamycin might not depend on the level of tau expression, because similar results were obtained in both the non-tau-expressing wild type human embryonic kidney 293 (HEK293) cells and HEK293 cells stably transfected with the longest isoform of recombinant human tau (tau441; HEK293/tau441). These findings suggest that rapamycin decreases pS214 via regulation of PKA. Because tau phosphorylation at Ser214 may prime tau for further phosphorylation by other kinases, our findings provide a novel possible mechanism by which rapamycin reduces or prevents tau hyperphosphorylation.

Pretreatment of PC12 cells with 17ß-estradiol prevents Aß-induced down-regulation of CREB phosphorylation and prolongs inhibition of GSK-3ß.

It is believed that estrogen protects neurons against various toxicities like that from amyloid ß (Aß) in Alzheimer's disease (AD). In the present study, we investigated the effects of Aß1-42 on the activities of cyclic-AMP response element-binding protein (CREB) and glycogen synthase kinase-3ß (GSK-3ß), two key proteins associated with learning and memory, and the effects of 17ß-estradiol on Aß(1-42)-induced changes of CREB and GSK-3ß in PC12 cells. We found that Aß1-42 induced a decrease in phosphorylation of CREB at Ser133 (CREB pS133) and caused a transient (30 min) up-regulation of the inhibitory GSK-3ß phosphorylation at Ser9 (GSK-3ß pS9), followed by down-regulation of GSK-3ß pS9. Pretreatment of 17ß-estradiol is needed for its protection against Aß1-42-induced changes of CREB. The protective role of 17ß-estradiol against Aß(1-42)-induced down-regulation of CREB pS133 was abolished by the mitogen-activated protein kinase (MAPK) pathway inhibitor U0126. Furthermore, 17ß-estradiol also prolonged the up-regulation of GSK-3ß pS9 for at least 8 h. However, this action of 17ß-estradiol was abrogated by PKA inhibitor H-89, AKT inhibitor LY294002, and MAPK inhibitor U0126. These results suggest that, while the protection of 17ß-estradiol on CREB is MAPK dependent, its effect on GSK-3ß integrates several pathways. These studies provide new insights into the role of estrogen in memory and AD.

Developmental regulation of protein O-GlcNAcylation, O-GlcNAc transferase, and O-GlcNAcase in mammalian brain.

O-GlcNAcylation is a common posttranslational modification of nucleocytoplasmic proteins by ß-N-acetylglucosamine (GlcNAc). The dynamic addition and removal of O-GlcNAc groups to and from proteins are catalyzed by O-linked N-acetylglucosamine transferase (O-GlcNAc transferase, OGT) and ß-N-acetylglucosaminidase (O-GlcNAcase, OGA), respectively. O-GlcNAcylation often modulates protein phosphorylation and regulates several cellular signaling and functions, especially in the brain. However, its developmental regulation is not well known. Here, we studied protein O-GlcNAcylation, OGT, and OGA in the rat brain at various ages from embryonic day 15 to the age of 2 years. We found a gradual decline of global protein O-GlcNAcylation during developmental stages and adulthood. This decline correlated positively to the total protein phosphorylation at serine residues, but not at threonine residues. The expression of OGT and OGA isoforms was regulated differently at various ages. Immunohistochemical studies revealed ubiquitous distribution of O-GlcNAcylation at all ages. Strong immunostaining of O-GlcNAc, OGT, and OGA was observed mostly in neuronal cell bodies and processes, further suggesting the role of O-GlcNAc modification of neuronal proteins in the brain. These studies provide fundamental knowledge of age-dependent protein modification by O-GlcNAc and will help guide future studies on the role of O-GlcNAcylation in the mammalian brain.

Tau phosphorylation and µ-calpain activation mediate the dexamethasone-induced inhibition on the insulin-stimulated Akt phosphorylation.

Evidence has suggested that insulin resistance (IR) or high levels of glucocorticoids (GCs) may be linked with the pathogenesis and/or progression of Alzheimer's disease (AD). Although studies have shown that a high level of GCs results in IR, little is known about the molecular details that link GCs and IR in the context of AD. Abnormal phosphorylation of tau and activation of µ-calpain are two key events in the pathology of AD. Importantly, these two events are also related with GCs and IR. We therefore speculate that tau phosphorylation and µ-calpain activation may mediate the GCs-induced IR. Akt phosphorylation at Ser-473 (pAkt) is commonly used as a marker for assessing IR. We employed two cell lines, wild-type HEK293 cells and HEK293 cells stably expressing the longest human tau isoform (tau-441; HEK293/tau441 cells). We examined whether DEX, a synthetic GCs, induces tau phosphorylation and µ-calpain activation. If so, we examined whether the DEX-induced tau phosphorylation and µ-calpain activation mediate the DEX-induced inhibition on the insulin-stimulated Akt phosphorylation. The results showed that DEX increased tau phosphorylation and induced tau-mediated µ-calpain activation. Furthermore, pre-treatment with LiCl prevented the effects of DEX on tau phosphorylation and µ-calpain activation. Finally, both LiCl pre-treatment and calpain inhibition prevented the DEX-induced inhibition on the insulin-stimulated Akt phosphorylation. In conclusion, our study suggests that the tau phosphorylation and µ-calpain activation mediate the DEX-induced inhibition on the insulin-stimulated Akt phosphorylation.

Differential effects of an O-GlcNAcase inhibitor on tau phosphorylation.

Abnormal hyperphosphorylation of microtubule-associated protein tau plays a crucial role in neurodegeneration in Alzheimer's disease (AD). The aggregation of hyperphosphorylated tau into neurofibrillary tangles is also a hallmark brain lesion of AD. Tau phosphorylation is regulated by tau kinases, tau phosphatases, and O-GlcNAcylation, a posttranslational modification of proteins on the serine or threonine residues with ß-N-acetylglucosamine (GlcNAc). O-GlcNAcylation is dynamically regulated by O-GlcNAc transferase, the enzyme catalyzing the transfer of GlcNAc to proteins, and N-acetylglucosaminidase (OGA), the enzyme catalyzing the removal of GlcNAc from proteins. Thiamet-G is a recently synthesized potent OGA inhibitor, and initial studies suggest it can influence O-GlcNAc levels in the brain, allowing OGA inhibition to be a potential route to altering disease progression in AD. In this study, we injected thiamet-G into the lateral ventricle of mice to increase O-GlcNAcylation of proteins and investigated the resulting effects on site-specific tau phosphorylation. We found that acute thiamet-G treatment led to a decrease in tau phosphorylation at Thr181, Thr212, Ser214, Ser262/Ser356, Ser404 and Ser409, and an increase in tau phosphorylation at Ser199, Ser202, Ser396 and Ser422 in the mouse brain. Investigation of the major tau kinases showed that acute delivery of a high dose of thiamet-G into the brain also led to a marked activation of glycogen synthase kinase-3ß (GSK-3ß), possibly as a consequence of down-regulation of its upstream regulating kinase, AKT. However, the elevation of tau phosphorylation at the sites above was not observed and GSK-3ß was not activated in cultured adult hippocampal progenitor cells or in PC12 cells after thiamet-G treatment. These results suggest that acute high-dose thiamet-G injection can not only directly antagonize tau phosphorylation, but also stimulate GSK-3ß activity, with the downstream consequence being site-specific, bi-directional regulation of tau phosphorylation in the mammalian brain.

Human tau may modify glucocorticoids-mediated regulation of cAMP-dependent kinase and phosphorylated cAMP response element binding protein.

Phosphorylation of the cAMP response element binding protein (CREB) by cAMP-dependent kinase (PKA) is critical to memory formation. However, activation of PKA can also increase tau phosphorylation, which may contribute to memory impairment. Therefore, the regulation of PKA may be part of the mechanism by which glucocorticoids (GCs) influence memory. Additionally, the cellular response to GCs may be affected by the presence of human tau. The goal of this paper was to study GCs-mediated regulation of PKA as well as CREB and tau phosphorylation in wild-type HEK293 cells and HEK293 cells stably expressing human tau441 (HEK293/tau441 cells). By using dexamethasone (DEX) as GCs, we found that DEX induced a tau-dependent selective decrease in the level of PKA RIIß subunit protein. The observed decrease in RIIß expression was not due to alterations of mRNA levels and was reversed by inhibiting the proteasome with lactacystin. Moreover, the decrease in RIIß did not diminish the co-localization of the catalytic subunit of PKA with tau and might contribute to the DEX-induced increase in tau phosphorylation at Ser-214. DEX also induced a tau-dependent decrease in CREB phosphorylation that could not be reversed by activating PKA with forskolin. Taken together, these results show that human tau protein may alter the GCs-mediated regulation of PKA activity and CREB phosphorylation.

1,5-dicaffeoylquinic acid protects primary neurons from amyloid ß 1-42-induced apoptosis via PI3K/Akt signaling pathway.

BACKGROUND: Recently, 1,5-dicaffeoylquinic acid (1,5-DQA), a caffeoylquinic acid derivative isolated from Aster scaber, was found to have neuroprotective effects. However, the protective mechanisms of 1,5-DQA have not yet been clearly identified. The purpose of this study was to explore the protective mechanisms of 1,5-DQA on neuronal culture. METHODS: We investigated the neuroprotective effects of 1,5-DQA against amyloid ß(1-42) (Aß(42))-induced neurotoxicity in primary neuronal culture. To evaluate the neuroprotective effects of 1,5-DQA, primary cultured cortical neurons from neonate rats were pretreated with 1,5-DQA for 2 hours and then treated with 40 µmol/L Aß(42) for 6 hours. Cell counting kit-8, Hoechst staining and Western blotting were used for detecting the protective mechanism. Comparisons between two groups were evaluated by independent t test, and multiple comparisons were analyzed by one-way analysis of variance (ANOVA). RESULTS: 1,5-DQA treated neurons showed increased neuronal cell viability against Aß(42) toxicity in a concentration-dependent manner, both phosphoinositide 3-kinase (PI3K)/Akt and extracellular regulated protein kinase 1/2 (Erk1/2) were activated by 1,5-DQA with stimulating their upstream tyrosine kinase A (Trk A). However, the neuroprotective effects of 1,5-DQA were blocked by LY294002, a PI3K inhibitor, but not by PD98059, an inhibitor of mitogen-activated protein kinase kinase. Furthermore, 1,5-DQA's anti-apoptotic potential was related to the enhanced inactivating phosphorylation of glycogen synthase kinase 3ß (GSK3ß) and the modulation of expression of apoptosis-related protein Bcl-2/Bax. CONCLUSION: These results suggest that 1,5-DQA prevents Aß(42)-induced neurotoxicity through the activation of PI3K/Akt followed by the stimulation of Trk A, then the inhibition of GSK3ß as well as the modulation of Bcl-2/Bax.

Anesthetics and tau protein: animal model studies.

Recent studies have suggested that general anesthesia may initiate or accelerate cognitive impairment and Alzheimer's disease (AD). To understand the possible underlying mechanisms, several studies have been carried out in animal models. In this review, we first briefly discuss the mechanisms leading to neurodegeneration and cognitive impairment in AD, with an emphasis on tau abnormalities in this pathological process. Subsequently, we review the role of anesthesia in inducing tau abnormalities and the possible mechanisms. Recent studies suggest that anesthesia may accelerate the development of AD by promoting abnormal hyperphosphorylation of tau. Further studies are certainly needed to understand the molecular mechanism by which anesthesia may initiate or accelerate cognitive impairment and AD. An understanding of the mechanism will help develop strategies for preventing or eliminating this adverse effect of anesthesia.

Anesthesia induces phosphorylation of tau.

Abnormal hyperphosphorylation and aggregation of microtubule-associated protein tau play a crucial role in neurodegeneration of Alzheimer's disease (AD). Anesthesia has been associated with cognitive impairment and the risk for AD. Here we investigated the effects of anesthesia on site-specific tau phosphorylation and the possible mechanisms. We found that anesthesia for short periods (30 sec to 5 min) induced tau phosphorylation at Thr181, Ser199, Thr205, Thr212, Ser262, and Ser404 to small, but significant, extents, which appeared to result from anesthesia-induced activation of stress-activated protein kinases. Anesthesia for a longer time (1~h) induced much more dramatic phosphorylation of tau at the above sites, and the further phosphorylation may be associated with hypothermia induced by anesthesia. Anesthesia-induced tau phosphorylation appears to be specific because the increased phosphorylation was only seen at half of the tau phosphorylation sites studied and was not observed in global brain proteins. These studies clarified the dynamic changes of tau phosphorylation at various sites and, thus, served as a fundamental guide for future studies on tau phosphorylation by using brains of anesthetized experimental animals. Our findings also provide a possible mechanism by which anesthesia may cause postoperative cognitive impairment and increase the risk for AD.

Developmental regulation of tau phosphorylation, tau kinases, and tau phosphatases.

Tau is a neuronal microtubule-associated protein. Its hyperphosphorylation plays a critical role in Alzheimer disease (AD). Expression and phosphorylation of tau are regulated developmentally, but its dynamic regulation and the responsible kinases or phosphatases remain elusive. Here, we studied the developmental regulation of tau in rats during development from embryonic day 15 through the age of 24 months. We found that tau expression increased sharply during the embryonic stage and then became relatively stable, whereas tau phosphorylation was much higher in developing brain than in mature brain. However, the extent of tau phosphorylation at seven of the 14 sites studied was much less in developing brain than in AD brain. Tau phosphorylation during development matched the period of active neurite outgrowth in general. Tau phosphorylation at various sites had different topographic distributions. Several tau kinases appeared to regulate tau phosphorylation collectively at overlapping sites, and the decrease of overall tau phosphorylation in adult brain might be due to the higher levels of tau phosphatases in mature brain. These studies provide new insight into the developmental regulation of site-specific tau phosphorylation and identify the likely sites required for the abnormal hyperphosphorylation of tau in AD.