1 Wnt/β-catenin signaling This signaling pathway is known to play key roles during development and in maintaining homeostasis in many adult tissues. Its aberrant activation is associated with cancers in many tissues
AIM:To study the activation of pancreatic and pulmonary mast cells and the effect of mast cell inhibition on the activation of peritoneal and alveolar macrophages during acute pancreatitis.METHODS:Pancreatitis was ind...AIM:To study the activation of pancreatic and pulmonary mast cells and the effect of mast cell inhibition on the activation of peritoneal and alveolar macrophages during acute pancreatitis.METHODS:Pancreatitis was induced by intraductal infusion of 5% sodium taurodeoxycholate in rats.The mast cell inhibitor cromolyn was administered intraperitoneally(i.p.) 30 min before pancreatitis induction.The pancreatic and pulmonary tissue damage was evaluated histologically and mast cells and their state of activation were evaluated.Peritoneal and alveolar macrophages were obtained and the expression of tumor necrosis factor α was determined.Myeloperoxidase activity was measured to evaluate the effect of mast cell inhibition on the progression of the inflammatory process.Finally,the effect of plasma on cultured mast cells or macrophages was evaluated in vitro.RESULTS:The mast cell stabilizer signif icantly reduced inflammation in the pancreas and lung and the activation of alveolar macrophages but had no effect on peritoneal macrophages.Mast cell degranulation was observed in the pancreas during pancreatitis but no changes were observed in the lung.Plasma from rats with pancreatitis could activate alveolar macrophages but did not induce degranulation of mast cells in vitro.CONCLUSION:Pancreatic mast cells play an important role in triggering the local and systemic inflammatory response in the early stages of acute pancreatitis.In contrast,lung mast cells are not directly involved in the inflammatory response related to pancreatic damage.展开更多
Neutrophils have emerged as key players in tumor progression and are often associated with poor prognosis.Despite ongoing efforts to target neutrophil functions in cancer,therapeutic success has been limited.In this s...Neutrophils have emerged as key players in tumor progression and are often associated with poor prognosis.Despite ongoing efforts to target neutrophil functions in cancer,therapeutic success has been limited.In this study,we addressed the possibility of blocking STAT3 signaling in neutrophils as a targeted therapeutic intervention in cancer.Conditional deletion of Stat3 in a neutrophil-specific manner(Ly6GcreStat3fl/fl mice)significantly impaired tumor growth and metastasis in mice.Neutrophils isolated from these mice exhibited a strong antitumoral phenotype,with increased MHCII,CD80/86 and ICAM-1 expression.Immune profiling of tumors and tumor-draining lymph nodes of these mice revealed significant enrichment of CD8^(+)T cells(granzymeB^(hi),perforin^(hi) and IFN-γ^(hi))with strong cytotoxic activity.To further translate these findings to human settings,we blocked STAT3 signaling in cancer patient neutrophils via the small molecule in^(hi)bitor LLL12 and assessed its effects on patient-derived tumor explants.In agreement with the in vivo mouse data,we observed the expansion and activation of cytotoxic CD8^(+)T cells in such explants.To test the therapeutic applicability of STAT3 targeting,we utilized myeloid cell-selective STAT3 antisense oligonucleotide(CpG-STAT3ASO)to target neutrophils in vivo in tumor-bearing mice.Consistent with previous results,neutrophil-specific STAT3 knockdown impaired tumor growth and enhanced cytotoxic T cell activity in the tumors and tumor-draining lymph nodes of treated mice.These findings highlight STAT3 signaling as a deleterious pathway supporting the protumoral activity of neutrophils and suggest that neutrophil-targeted STAT3 in^(hi)bition is a promising opportunity for cancer immunotherapy,providing novel insights into targeted therapeutic avenues.展开更多
The role of chronic inflammation,acting as an independent factor,on the onset of gastrointestinal carcinogenesis is now well accepted.However,even if there is an increase in the number of elements directly involving p...The role of chronic inflammation,acting as an independent factor,on the onset of gastrointestinal carcinogenesis is now well accepted.However,even if there is an increase in the number of elements directly involving polymorphonuclear leukocytes (PMNL),as a major actor in digestive carcinogenesis,the different cellular and molecular events occurring in this process are still not completely understood.The transepithelial migration of PMNL,which is the ultimate step of the afflux of PMNL into the digestive mucosa,is a complex phenomenon involving sequential interaction of molecules expressed both on PMNL and on digestive epithelial cells.Chronic inflammatory areas rich in PMNL [so-called (chronic active inflammation)] and iterative transepithelial migration of PMNL certainly evoke intracellular signals,which lead toward progressive transformation of epithelia.Among these different signals,the mutagenic effect of reactive oxygen species and nitrates,the activation of the nuclear factor-κB pathway,and the modulation of expression of certain microRNA are key actors.Following the initiation of carcinogenesis,PMNL are involved in the progression and invasion of digestive carcinomas,with which they interact.It is noteworthy that different subpopulations of PMNL,which can have some opposite effects on tumor growth,in association with different levels of transforming growth factor-β and with the number of CD8 positive T lymphocytes,could be present during the development of digestive carcinoma.Other factors that involve PMNL,such as massive elastase release,and the production of angiogenic factors,can participate in the progression of neoplastic cells through tissues.PMNL may play a major role in the onset of metastases,since they allow the tumor cells to cross the endothelial barrier and to migrate into the blood stream.Finally,PMNL play a role,alone or in association with other cell parameters,in the initiation,promotion,progression and dissemination of digestive carcinomas.This review focuses on the main currently accepted cellular and molecular mechanisms that involve PMNL as key actors in digestive carcinogenesis.展开更多
Viral-mediated gene transfer of thymidine kinase ofherpes simplex virus (HSV-tk) has been used to confercytotoxic sensitivity to ganciclovir (GCV) in a variety oftnmor cells. HSV-tk converts GCV into a phosphorylatedc...Viral-mediated gene transfer of thymidine kinase ofherpes simplex virus (HSV-tk) has been used to confercytotoxic sensitivity to ganciclovir (GCV) in a variety oftnmor cells. HSV-tk converts GCV into a phosphorylatedcompound which is toxic for dividing cells by blockingDNA synthesis. Our previous study has shown展开更多
AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B1 (AFB1) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis.METH...AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B1 (AFB1) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis.METHODS: Tree shrews were divided into four groups:group A, those infected with HBV and fed with AFB1 (n = 39);group B, those infected with HBV alone (n = 28); group C,those fed with AFB1 alone (n = 29); and group D, normal controls (n = 20). The tree shrews underwent liver biopsies once every 15 wk. Expression of p53 and p21 proteins and genes in the biopsies and tumor tissues of the experimental tree shrews was detected, respectively, by immunohistochemistry,and by Southem blotting and reverse transcription-polymerase chain reaction and sequencing.RESULTS: The incidence of hepatocellular carcinomas (HCC) was higher in group A (66.7%) than that in group B (3.57%) and C (30%). The time of HCC occurrence was also earlier in group A than that in group C (120.0±16.6 wk vs 153.3±5.8 wk, respectively, P<0.01). p53 protein was not detected by immunohistochemistry in all groups before the 75^th wk of the experiment. At the 105^th wk, the positive rates fo p53 were 78.6%, 60% and 71.4% in groups A, B and C, respectively, which were significantly higher than that in group D (10%) (all P<0.05). An abnormal band of p53 gene was observed in groups A and C. The mutation points of p53gene in tree shrews with HCC were at codons 275, 78 and 13. The nucleotide sequence and amino acid sequence of tree shrew's wild-type p53 showed 91.7% and 93.4% homologies with those of human p53,respectively. The immunopositivity for p21 was found before HCC development. The incidence of HCC was significantly higher in tree shrews that were positive for p21 than those negative for p21 (80.0% vs 11.0%, P<0.001).The incidence of HCC in p21 positive animals in group A was significantly higher than those positive for p21 in group C (P<O.05).CONCLUSION: A remarkable synergistic effect on HCC development exists between HBV and AFB1. p53 mutation promotes the development of HCC. HBV and AFB1 may synergistically induce p53 gene mutation, and stimulate ras gene expression, ras gene is activated at the earlier stage during hepatocarcinogenesis, p21 protein may be an early marker, and the alterations of p53 may be a late event in the development of HCC.展开更多
Long-standing inflammation has emerged as a hallmark of neoplastic transformation of epithelial cells and may be a limiting factor of successful conventional tumor therapies.A complex milieu composed of distinct strom...Long-standing inflammation has emerged as a hallmark of neoplastic transformation of epithelial cells and may be a limiting factor of successful conventional tumor therapies.A complex milieu composed of distinct stromal and immune cells,soluble factors and inflammatory mediators plays a crucial role in supporting and promoting various types of cancers.An augmented inflammatory response can predispose a patient to colorectal cancer(CRC).Common risk factors associated with CRC development include diet and lifestyle,altered intestinal microbiota and commensals,and chronic inflammatory bowel diseases.Cysteinyl leukotrienes are potent inflammatory metabolites synthesized from arachidonic acid and have a broad range of functions involved in the etiology of various pathologies.This review discusses the important role of cysteinyl leukotriene signaling in linking inflammation and CRC.展开更多
AIM To investigate the hepatitis C virus(HCV)infection in the tissues of carcinoma ofextrahepatic bile duct and study theircorrelation.METHODS HCV NS5 protein and HCV RNA weredetected by labeled streptavidin biotin(LS...AIM To investigate the hepatitis C virus(HCV)infection in the tissues of carcinoma ofextrahepatic bile duct and study theircorrelation.METHODS HCV NS5 protein and HCV RNA weredetected by labeled streptavidin biotin(LSAB)method and in situ reverse transcriptionpolymerase chain reaction(IS-RT-PCR)insections of 51 cases of carcinoma ofextrahepatic bile duct and 34 cases of controlgroup(without malignant biliary disease).RESULTS In 51 cases of carcinoma ofextrahepatic bile duct,HCV NS5 protein wasdetected in 14(27.5%),which was clearlystained in the cytoplasm of cancer cell but not inthe nucleus or cell membrane.HCV RNA wasdetected in 18(35.4%),which was located inthe nucleus of cancer cell in 12 cases and in thecytoplasm in 6 cases.HCV NS5 protein and RNAcoexistence was found in 2 cases.In 34 cases ofcontrol group,HCV RNA was detected in 2(5.9%).HCV NS5 protein and RNA positive cellswere found either scattered or in clusters.CONCLUSION The prevalence of hepatitis C viral infection in the tissues of carcinoma ofextrahepatic bile duct was significantly higherthan in control group(X^2=9.808,P=0.002).The findings suggest a correlation between HCVinfection and carcinoma of extrahepatic bileduct,which is different from the traditionalviewpoint.HCV infection might be involved inthe development of carcinoma of extrahepaticbile duct.展开更多
With key roles in essential brain functions ranging from the long-term potentiation(LTP) to synaptic plasticity,the N-methyl-D-aspartic acid receptor(NMDAR) can be considered as one of the fundamental glutamate recept...With key roles in essential brain functions ranging from the long-term potentiation(LTP) to synaptic plasticity,the N-methyl-D-aspartic acid receptor(NMDAR) can be considered as one of the fundamental glutamate receptors in the central nervous system.The role of NMDA R was first identified in synaptic plasticity and has been extensively studied.Some molecules,such as Ca^(2+),postsynaptic density 95(PSD-95),calcium/calmodulin-dependent protein kinase II(Ca MK II),protein kinase A(PKA),mitogen-activated protein kinase(MAPK) and cyclic adenosine monophosphate(c AMP) responsive element binding protein(CREB),are of special importance in learning and memory.This review mainly focused on the new research of key molecules connected with learning and memory,which played important roles in the NMDAR signaling pathway.展开更多
Hepatic encephalopathy(HE)is a neuropsychiatric complex syndrome,ranging from subtle behavioral abnormalities to deep coma and death.Hepatic encephalopathy emerges as the major complication of acute or chronic liver f...Hepatic encephalopathy(HE)is a neuropsychiatric complex syndrome,ranging from subtle behavioral abnormalities to deep coma and death.Hepatic encephalopathy emerges as the major complication of acute or chronic liver failure.Multiplicity of factors are involved in its pathophysiology,such as central and neuromuscular neurotransmission disorder,alterations in sleep patterns and cognition,changes in energy metabolism leading to cell injury,an oxidative/nitrosative state and a neuroinflammatory condition.Moreover,in acute HE,a condition of imminent threat of death is present due to a deleterious astrocyte swelling.In chronic HE,changes in calcium signaling,mitochondrial membrane potential and long term potential expression,N-methyl-D-aspartate-cGMP and peripheral benzodiazepine receptors alterations,and changes in the mRNA and protein expression and redistribution in the cerebral blood flow can be observed.The main molecule indicated as responsible for all these changes in HE is ammonia.There is no doubt that ammonia,a neurotoxic molecule,triggers or at least facilitates most of these changes.Ammonia plasma levels are increased two-to three-fold in patients with mild to moderate cirrhotic HE and up to ten-fold in patients with acute liver failure. Hepatic and inter-organ trafficking of ammonia and its metabolite,glutamine(GLN),lead to hyperammonemic conditions.Removal of hepatic ammonia is a differentiated work that includes the hepatocyte,through the urea cycle,converting ammonia into GLN via glutamine synthetase.Under pathological conditions,such as liver damage or liver blood bypass,the ammonia plasma level starts to rise and the risk of HE developing is high. Knowledge of the pathophysiology of HE is rapidly expanding and identification of focally localized triggers has led the development of new possibilities for HE to be considered.This editorial will focus on issues where, to the best of our knowledge,more research is needed in order to clarify,at least partially,controversial topics.展开更多
Signal transducers and activators of transcription 3 (STAT3) play an important role in various autoimmune disorders including inflammatory bowel disease (IBD). Recent studies have revealed that STAT3 activation plays ...Signal transducers and activators of transcription 3 (STAT3) play an important role in various autoimmune disorders including inflammatory bowel disease (IBD). Recent studies have revealed that STAT3 activation plays distinctly different roles between innate immune responses and acquired immune responses in colitis. STAT3-mediated activation of acquired immune re-sponses plays a pathogenic role in colitis by enhancing the survival of pathogenic T cells. In contrast, STAT3-mediated activation of innate responses contributes to the suppression of colitis. This review will summarize the current understanding of the roles of STAT3 in IBD and the potential of targeting STAT3 for the treatment of IBD, emphasizing recent observations.展开更多
Objective To estimate the detrimental effects of shortwave exposure on rat hippocampal structure and function and explore the underlying mechanisms. Methods One hundred Wistar rats were randomly divided into four grou...Objective To estimate the detrimental effects of shortwave exposure on rat hippocampal structure and function and explore the underlying mechanisms. Methods One hundred Wistar rats were randomly divided into four groups(25 rats per group) and exposed to 27 MHz continuous shortwave at a power density of 5, 10, or 30 m W/cm^2 for 6 min once only or underwent sham exposure for the control. The spatial learning and memory, electroencephalogram(EEG), hippocampal structure and Nissl bodies were analysed. Furthermore, the expressions of N-methyl-D-aspartate receptor(NMDAR) subunits(NR1, NR2 A, and NR2 B), c AMP responsive element-binding protein(CREB) and phosphorylated CREB(p-CREB) in hippocampal tissue were analysed on 1, 7, and 14 days after exposure. Results The rats in the 10 and 30 m W/cm^2 groups had poor learning and memory, disrupted EEG oscillations, and injured hippocampal structures, including hippocampal neurons degeneration, mitochondria cavitation and blood capillaries swelling. The Nissl body content was also reduced in the exposure groups. Moreover, the hippocampal tissue in the 30 m W/cm^2 group had increased expressions of NR2 A and NR2 B and decreased levels of CREB and p-CREB. Conclusion Shortwave exposure(27 MHz, with an average power density of 10 and 30 m W/cm^2) impaired rats' spatial learning and memory and caused a series of dose-dependent pathophysiological changes. Moreover, NMDAR-related CREB pathway suppression might be involved in shortwave-induced structural and functional impairments in the rat hippocampus.展开更多
In addition to pancreatic cells,other inflammatory cell populations contribute to the generation of inflammatory mediators during acute pancreatitis.In particular,macrophages could be activated by mediators released d...In addition to pancreatic cells,other inflammatory cell populations contribute to the generation of inflammatory mediators during acute pancreatitis.In particular,macrophages could be activated by mediators released during pancreatitis by a damaged pancreas.It has been reported that peritoneal macrophages,alveolar macrophages and Kupffer cells become activated in different stages of severe acute pancreatitis.However,macrophages display remarkable plasticity and can change their physiology in response to environmental cues.Depending on their microenvironmental stimulation,macrophages could follow different activation pathways resulting in marked phenotypic heterogeneity.This ability has made these cells interesting therapeutical targets and several approaches have been assayed to modulate the progression of inflammatory response secondary to acute pancreatitis.However,despite the recent advances in the modulation of macrophage function in vivo,the therapeutical applications of these strategies require a better understanding of the regulation of gene expression in these cells.展开更多
Studies on rodents and humans demonstrate an inherited predisposition to hepatocellular carcinoma （HCC）. Analysis of the molecular alterations involved in the acquisition of a phenotype resistant or susceptible to h...Studies on rodents and humans demonstrate an inherited predisposition to hepatocellular carcinoma （HCC）. Analysis of the molecular alterations involved in the acquisition of a phenotype resistant or susceptible to hepatocarcinogenesis showed a deregulation of G1 and S phases in HCC of genetically susceptible F344 rats and a G1-S block in lesions of resistant Brown norway （BN） rats. Unrestrained extracellular signal-regulated kinase （ERK） activity linked to proteasomal degradation of dual-specificity phosphatase 1 （DUSP1）, a specific ERK inhibitor, by the CKS1-SKP2 ubiquitin ligase complex occurs in more aggressive HCC of F344 rats and humans. This mechanism is less active in HCC of BN rats and human HCC with better prognosis. Upregulation of iNos cross-talk with IKK/NF-KB and RAS/ERK pathways occurs in rodent liver lesions at higher levels in the most aggressive models represented by HCC of F344 rats and c-Myc-TGF-α transgenic mice. iNOS, IKK/NF-κB, and RAS/ERK upregulation is highest in human HCC with a poorer prognosis and positively correlates with tumor proliferation, genomic instability and microvascularization, and negatively with apoptosis. Thus, cell cycle regulation and the activity of signal transduction pathways seem to be modulated by HCC modifier genes, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC.展开更多
Pancreatitis-associated protein (PAP) was discovered in the pancreatic juice of rats with acute pancreatitis. PAP is a 16 kDa secretory protein structurally related to the C-type lectins although classical lectin-rela...Pancreatitis-associated protein (PAP) was discovered in the pancreatic juice of rats with acute pancreatitis. PAP is a 16 kDa secretory protein structurally related to the C-type lectins although classical lectin-related function has not been reported yet. Then, it was demonstrated that PAP expression may be activated in some tissues in a constitutive or injury- and inflammation-induced manner. More recently, it has been found that PAP acts as an anti-inflammatory factor in vitro and in vivo. PAP expression can be induced by several pro- and anti-inflammatory cytokines and by itself through a JAK/STAT3-dependent pathway. PAP is able to activate the expression of the anti-inflammatory factor SOCS3 through the JAK/STAT3-dependent pathway. The JAK/STAT3/SOCS3 pathway seems to be a common point between PAP and several cytokines. Therefore, it is reasonable to propose that PAP is a new anti- inflammatory cytokine.展开更多
A major issue in organ transplantation is the development of a protocol that can preserve organs under optimal conditions. Damage to organs is commonly a consequence of flow deprivation and oxygen starvation following...A major issue in organ transplantation is the development of a protocol that can preserve organs under optimal conditions. Damage to organs is commonly a consequence of flow deprivation and oxygen starvation following the restoration of blood flow and reoxygenation. This is known as ischemia-reperfusion injury(IRI): a complex multifactorial process that causes cell damage. While the oxygen deprivation due to ischemia depletes cell energy, subsequent tissue oxygenation due to reperfusion induces many cascades, from reactive oxygen species production to apoptosis initiation. Autophagy has also been identified in the pathogenesis of IRI, although such alterations and their subsequent functional significance are controversial. Moreover, proteasome activation may be a relevant pathophysiological mechanism. Different strategies have been adopted to limit IRI damage, including the supplementation of commercial preservation media with pharmacological agents or additives. In this review, we focus on novel strategies related to the ubiquitin proteasome system and oxidative stress inhibition, which have been used to minimize damage in liver transplantation.展开更多
The terahertz(THz) band lies between microwave and infrared rays in wavelength and consists of non-ionizing radiation. Both domestic and foreign research institutions, including the army, have attached considerable im...The terahertz(THz) band lies between microwave and infrared rays in wavelength and consists of non-ionizing radiation. Both domestic and foreign research institutions, including the army, have attached considerable importance to the research and development of THz technology because this radiation exhibits both photon-like and electron-like properties, which grant it considerable application value and potential. With the rapid development of THz technology and related applications, studies of the biological effects of THz radiation have become a major focus in the field of life sciences. Research in this field has only just begun, both at home and abroad. In this paper, research progress with respect to THz radiation, including its biological effects, mechanisms and methods of protection, will be reviewed.展开更多
文摘1 Wnt/β-catenin signaling This signaling pathway is known to play key roles during development and in maintaining homeostasis in many adult tissues. Its aberrant activation is associated with cancers in many tissues
基金Supported by The Project SAF2006-08449 and agrant from Fundación para la Investigación del Hospital General Universitario de AlicanteInmaculada Lopez-Font has a Juan de la Cierva contract supported by the Spanish Ministry of Science and Innovation
文摘AIM:To study the activation of pancreatic and pulmonary mast cells and the effect of mast cell inhibition on the activation of peritoneal and alveolar macrophages during acute pancreatitis.METHODS:Pancreatitis was induced by intraductal infusion of 5% sodium taurodeoxycholate in rats.The mast cell inhibitor cromolyn was administered intraperitoneally(i.p.) 30 min before pancreatitis induction.The pancreatic and pulmonary tissue damage was evaluated histologically and mast cells and their state of activation were evaluated.Peritoneal and alveolar macrophages were obtained and the expression of tumor necrosis factor α was determined.Myeloperoxidase activity was measured to evaluate the effect of mast cell inhibition on the progression of the inflammatory process.Finally,the effect of plasma on cultured mast cells or macrophages was evaluated in vitro.RESULTS:The mast cell stabilizer signif icantly reduced inflammation in the pancreas and lung and the activation of alveolar macrophages but had no effect on peritoneal macrophages.Mast cell degranulation was observed in the pancreas during pancreatitis but no changes were observed in the lung.Plasma from rats with pancreatitis could activate alveolar macrophages but did not induce degranulation of mast cells in vitro.CONCLUSION:Pancreatic mast cells play an important role in triggering the local and systemic inflammatory response in the early stages of acute pancreatitis.In contrast,lung mast cells are not directly involved in the inflammatory response related to pancreatic damage.
基金support from the Open Access Publication Fund of the University of Duisburg-Essensupported by the Deutsche Forschungsgemeinschaft(DFG/JA-2461/7-1)+1 种基金CRC TRR332 project A05 to JJthe Stiftung Tumorforschung Kopf-Hals to CK.
文摘Neutrophils have emerged as key players in tumor progression and are often associated with poor prognosis.Despite ongoing efforts to target neutrophil functions in cancer,therapeutic success has been limited.In this study,we addressed the possibility of blocking STAT3 signaling in neutrophils as a targeted therapeutic intervention in cancer.Conditional deletion of Stat3 in a neutrophil-specific manner(Ly6GcreStat3fl/fl mice)significantly impaired tumor growth and metastasis in mice.Neutrophils isolated from these mice exhibited a strong antitumoral phenotype,with increased MHCII,CD80/86 and ICAM-1 expression.Immune profiling of tumors and tumor-draining lymph nodes of these mice revealed significant enrichment of CD8^(+)T cells(granzymeB^(hi),perforin^(hi) and IFN-γ^(hi))with strong cytotoxic activity.To further translate these findings to human settings,we blocked STAT3 signaling in cancer patient neutrophils via the small molecule in^(hi)bitor LLL12 and assessed its effects on patient-derived tumor explants.In agreement with the in vivo mouse data,we observed the expansion and activation of cytotoxic CD8^(+)T cells in such explants.To test the therapeutic applicability of STAT3 targeting,we utilized myeloid cell-selective STAT3 antisense oligonucleotide(CpG-STAT3ASO)to target neutrophils in vivo in tumor-bearing mice.Consistent with previous results,neutrophil-specific STAT3 knockdown impaired tumor growth and enhanced cytotoxic T cell activity in the tumors and tumor-draining lymph nodes of treated mice.These findings highlight STAT3 signaling as a deleterious pathway supporting the protumoral activity of neutrophils and suggest that neutrophil-targeted STAT3 in^(hi)bition is a promising opportunity for cancer immunotherapy,providing novel insights into targeted therapeutic avenues.
文摘The role of chronic inflammation,acting as an independent factor,on the onset of gastrointestinal carcinogenesis is now well accepted.However,even if there is an increase in the number of elements directly involving polymorphonuclear leukocytes (PMNL),as a major actor in digestive carcinogenesis,the different cellular and molecular events occurring in this process are still not completely understood.The transepithelial migration of PMNL,which is the ultimate step of the afflux of PMNL into the digestive mucosa,is a complex phenomenon involving sequential interaction of molecules expressed both on PMNL and on digestive epithelial cells.Chronic inflammatory areas rich in PMNL [so-called (chronic active inflammation)] and iterative transepithelial migration of PMNL certainly evoke intracellular signals,which lead toward progressive transformation of epithelia.Among these different signals,the mutagenic effect of reactive oxygen species and nitrates,the activation of the nuclear factor-κB pathway,and the modulation of expression of certain microRNA are key actors.Following the initiation of carcinogenesis,PMNL are involved in the progression and invasion of digestive carcinomas,with which they interact.It is noteworthy that different subpopulations of PMNL,which can have some opposite effects on tumor growth,in association with different levels of transforming growth factor-β and with the number of CD8 positive T lymphocytes,could be present during the development of digestive carcinoma.Other factors that involve PMNL,such as massive elastase release,and the production of angiogenic factors,can participate in the progression of neoplastic cells through tissues.PMNL may play a major role in the onset of metastases,since they allow the tumor cells to cross the endothelial barrier and to migrate into the blood stream.Finally,PMNL play a role,alone or in association with other cell parameters,in the initiation,promotion,progression and dissemination of digestive carcinomas.This review focuses on the main currently accepted cellular and molecular mechanisms that involve PMNL as key actors in digestive carcinogenesis.
文摘Viral-mediated gene transfer of thymidine kinase ofherpes simplex virus (HSV-tk) has been used to confercytotoxic sensitivity to ganciclovir (GCV) in a variety oftnmor cells. HSV-tk converts GCV into a phosphorylatedcompound which is toxic for dividing cells by blockingDNA synthesis. Our previous study has shown
基金Supported by the National Natural Science Foundation of China,No.39260033Natural Science Foundation of Guangxi,No.0143058
文摘AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B1 (AFB1) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis.METHODS: Tree shrews were divided into four groups:group A, those infected with HBV and fed with AFB1 (n = 39);group B, those infected with HBV alone (n = 28); group C,those fed with AFB1 alone (n = 29); and group D, normal controls (n = 20). The tree shrews underwent liver biopsies once every 15 wk. Expression of p53 and p21 proteins and genes in the biopsies and tumor tissues of the experimental tree shrews was detected, respectively, by immunohistochemistry,and by Southem blotting and reverse transcription-polymerase chain reaction and sequencing.RESULTS: The incidence of hepatocellular carcinomas (HCC) was higher in group A (66.7%) than that in group B (3.57%) and C (30%). The time of HCC occurrence was also earlier in group A than that in group C (120.0±16.6 wk vs 153.3±5.8 wk, respectively, P<0.01). p53 protein was not detected by immunohistochemistry in all groups before the 75^th wk of the experiment. At the 105^th wk, the positive rates fo p53 were 78.6%, 60% and 71.4% in groups A, B and C, respectively, which were significantly higher than that in group D (10%) (all P<0.05). An abnormal band of p53 gene was observed in groups A and C. The mutation points of p53gene in tree shrews with HCC were at codons 275, 78 and 13. The nucleotide sequence and amino acid sequence of tree shrew's wild-type p53 showed 91.7% and 93.4% homologies with those of human p53,respectively. The immunopositivity for p21 was found before HCC development. The incidence of HCC was significantly higher in tree shrews that were positive for p21 than those negative for p21 (80.0% vs 11.0%, P<0.001).The incidence of HCC in p21 positive animals in group A was significantly higher than those positive for p21 in group C (P<O.05).CONCLUSION: A remarkable synergistic effect on HCC development exists between HBV and AFB1. p53 mutation promotes the development of HCC. HBV and AFB1 may synergistically induce p53 gene mutation, and stimulate ras gene expression, ras gene is activated at the earlier stage during hepatocarcinogenesis, p21 protein may be an early marker, and the alterations of p53 may be a late event in the development of HCC.
文摘Long-standing inflammation has emerged as a hallmark of neoplastic transformation of epithelial cells and may be a limiting factor of successful conventional tumor therapies.A complex milieu composed of distinct stromal and immune cells,soluble factors and inflammatory mediators plays a crucial role in supporting and promoting various types of cancers.An augmented inflammatory response can predispose a patient to colorectal cancer(CRC).Common risk factors associated with CRC development include diet and lifestyle,altered intestinal microbiota and commensals,and chronic inflammatory bowel diseases.Cysteinyl leukotrienes are potent inflammatory metabolites synthesized from arachidonic acid and have a broad range of functions involved in the etiology of various pathologies.This review discusses the important role of cysteinyl leukotriene signaling in linking inflammation and CRC.
文摘AIM To investigate the hepatitis C virus(HCV)infection in the tissues of carcinoma ofextrahepatic bile duct and study theircorrelation.METHODS HCV NS5 protein and HCV RNA weredetected by labeled streptavidin biotin(LSAB)method and in situ reverse transcriptionpolymerase chain reaction(IS-RT-PCR)insections of 51 cases of carcinoma ofextrahepatic bile duct and 34 cases of controlgroup(without malignant biliary disease).RESULTS In 51 cases of carcinoma ofextrahepatic bile duct,HCV NS5 protein wasdetected in 14(27.5%),which was clearlystained in the cytoplasm of cancer cell but not inthe nucleus or cell membrane.HCV RNA wasdetected in 18(35.4%),which was located inthe nucleus of cancer cell in 12 cases and in thecytoplasm in 6 cases.HCV NS5 protein and RNAcoexistence was found in 2 cases.In 34 cases ofcontrol group,HCV RNA was detected in 2(5.9%).HCV NS5 protein and RNA positive cellswere found either scattered or in clusters.CONCLUSION The prevalence of hepatitis C viral infection in the tissues of carcinoma ofextrahepatic bile duct was significantly higherthan in control group(X^2=9.808,P=0.002).The findings suggest a correlation between HCVinfection and carcinoma of extrahepatic bileduct,which is different from the traditionalviewpoint.HCV infection might be involved inthe development of carcinoma of extrahepaticbile duct.
基金supported by the National Natural Science Foundation of China(61401497)
文摘With key roles in essential brain functions ranging from the long-term potentiation(LTP) to synaptic plasticity,the N-methyl-D-aspartic acid receptor(NMDAR) can be considered as one of the fundamental glutamate receptors in the central nervous system.The role of NMDA R was first identified in synaptic plasticity and has been extensively studied.Some molecules,such as Ca^(2+),postsynaptic density 95(PSD-95),calcium/calmodulin-dependent protein kinase II(Ca MK II),protein kinase A(PKA),mitogen-activated protein kinase(MAPK) and cyclic adenosine monophosphate(c AMP) responsive element binding protein(CREB),are of special importance in learning and memory.This review mainly focused on the new research of key molecules connected with learning and memory,which played important roles in the NMDAR signaling pathway.
文摘Hepatic encephalopathy(HE)is a neuropsychiatric complex syndrome,ranging from subtle behavioral abnormalities to deep coma and death.Hepatic encephalopathy emerges as the major complication of acute or chronic liver failure.Multiplicity of factors are involved in its pathophysiology,such as central and neuromuscular neurotransmission disorder,alterations in sleep patterns and cognition,changes in energy metabolism leading to cell injury,an oxidative/nitrosative state and a neuroinflammatory condition.Moreover,in acute HE,a condition of imminent threat of death is present due to a deleterious astrocyte swelling.In chronic HE,changes in calcium signaling,mitochondrial membrane potential and long term potential expression,N-methyl-D-aspartate-cGMP and peripheral benzodiazepine receptors alterations,and changes in the mRNA and protein expression and redistribution in the cerebral blood flow can be observed.The main molecule indicated as responsible for all these changes in HE is ammonia.There is no doubt that ammonia,a neurotoxic molecule,triggers or at least facilitates most of these changes.Ammonia plasma levels are increased two-to three-fold in patients with mild to moderate cirrhotic HE and up to ten-fold in patients with acute liver failure. Hepatic and inter-organ trafficking of ammonia and its metabolite,glutamine(GLN),lead to hyperammonemic conditions.Removal of hepatic ammonia is a differentiated work that includes the hepatocyte,through the urea cycle,converting ammonia into GLN via glutamine synthetase.Under pathological conditions,such as liver damage or liver blood bypass,the ammonia plasma level starts to rise and the risk of HE developing is high. Knowledge of the pathophysiology of HE is rapidly expanding and identification of focally localized triggers has led the development of new possibilities for HE to be considered.This editorial will focus on issues where, to the best of our knowledge,more research is needed in order to clarify,at least partially,controversial topics.
文摘Signal transducers and activators of transcription 3 (STAT3) play an important role in various autoimmune disorders including inflammatory bowel disease (IBD). Recent studies have revealed that STAT3 activation plays distinctly different roles between innate immune responses and acquired immune responses in colitis. STAT3-mediated activation of acquired immune re-sponses plays a pathogenic role in colitis by enhancing the survival of pathogenic T cells. In contrast, STAT3-mediated activation of innate responses contributes to the suppression of colitis. This review will summarize the current understanding of the roles of STAT3 in IBD and the potential of targeting STAT3 for the treatment of IBD, emphasizing recent observations.
基金supported by the National Natural Science Fund [No.31570847]the fund organization had no role in the design or conduct of this research
文摘Objective To estimate the detrimental effects of shortwave exposure on rat hippocampal structure and function and explore the underlying mechanisms. Methods One hundred Wistar rats were randomly divided into four groups(25 rats per group) and exposed to 27 MHz continuous shortwave at a power density of 5, 10, or 30 m W/cm^2 for 6 min once only or underwent sham exposure for the control. The spatial learning and memory, electroencephalogram(EEG), hippocampal structure and Nissl bodies were analysed. Furthermore, the expressions of N-methyl-D-aspartate receptor(NMDAR) subunits(NR1, NR2 A, and NR2 B), c AMP responsive element-binding protein(CREB) and phosphorylated CREB(p-CREB) in hippocampal tissue were analysed on 1, 7, and 14 days after exposure. Results The rats in the 10 and 30 m W/cm^2 groups had poor learning and memory, disrupted EEG oscillations, and injured hippocampal structures, including hippocampal neurons degeneration, mitochondria cavitation and blood capillaries swelling. The Nissl body content was also reduced in the exposure groups. Moreover, the hippocampal tissue in the 30 m W/cm^2 group had increased expressions of NR2 A and NR2 B and decreased levels of CREB and p-CREB. Conclusion Shortwave exposure(27 MHz, with an average power density of 10 and 30 m W/cm^2) impaired rats' spatial learning and memory and caused a series of dose-dependent pathophysiological changes. Moreover, NMDAR-related CREB pathway suppression might be involved in shortwave-induced structural and functional impairments in the rat hippocampus.
文摘In addition to pancreatic cells,other inflammatory cell populations contribute to the generation of inflammatory mediators during acute pancreatitis.In particular,macrophages could be activated by mediators released during pancreatitis by a damaged pancreas.It has been reported that peritoneal macrophages,alveolar macrophages and Kupffer cells become activated in different stages of severe acute pancreatitis.However,macrophages display remarkable plasticity and can change their physiology in response to environmental cues.Depending on their microenvironmental stimulation,macrophages could follow different activation pathways resulting in marked phenotypic heterogeneity.This ability has made these cells interesting therapeutical targets and several approaches have been assayed to modulate the progression of inflammatory response secondary to acute pancreatitis.However,despite the recent advances in the modulation of macrophage function in vivo,the therapeutical applications of these strategies require a better understanding of the regulation of gene expression in these cells.
基金Supported by Grants from the"Associazione Italiana Ricerche sul Cancro"
文摘Studies on rodents and humans demonstrate an inherited predisposition to hepatocellular carcinoma （HCC）. Analysis of the molecular alterations involved in the acquisition of a phenotype resistant or susceptible to hepatocarcinogenesis showed a deregulation of G1 and S phases in HCC of genetically susceptible F344 rats and a G1-S block in lesions of resistant Brown norway （BN） rats. Unrestrained extracellular signal-regulated kinase （ERK） activity linked to proteasomal degradation of dual-specificity phosphatase 1 （DUSP1）, a specific ERK inhibitor, by the CKS1-SKP2 ubiquitin ligase complex occurs in more aggressive HCC of F344 rats and humans. This mechanism is less active in HCC of BN rats and human HCC with better prognosis. Upregulation of iNos cross-talk with IKK/NF-KB and RAS/ERK pathways occurs in rodent liver lesions at higher levels in the most aggressive models represented by HCC of F344 rats and c-Myc-TGF-α transgenic mice. iNOS, IKK/NF-κB, and RAS/ERK upregulation is highest in human HCC with a poorer prognosis and positively correlates with tumor proliferation, genomic instability and microvascularization, and negatively with apoptosis. Thus, cell cycle regulation and the activity of signal transduction pathways seem to be modulated by HCC modifier genes, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC.
文摘Pancreatitis-associated protein (PAP) was discovered in the pancreatic juice of rats with acute pancreatitis. PAP is a 16 kDa secretory protein structurally related to the C-type lectins although classical lectin-related function has not been reported yet. Then, it was demonstrated that PAP expression may be activated in some tissues in a constitutive or injury- and inflammation-induced manner. More recently, it has been found that PAP acts as an anti-inflammatory factor in vitro and in vivo. PAP expression can be induced by several pro- and anti-inflammatory cytokines and by itself through a JAK/STAT3-dependent pathway. PAP is able to activate the expression of the anti-inflammatory factor SOCS3 through the JAK/STAT3-dependent pathway. The JAK/STAT3/SOCS3 pathway seems to be a common point between PAP and several cytokines. Therefore, it is reasonable to propose that PAP is a new anti- inflammatory cytokine.
基金Supported by Fondo de Investigaciones Sanitarias,Ministerio de Economia y Competitividad(Madrid,Spain),No.PI15/00110
文摘A major issue in organ transplantation is the development of a protocol that can preserve organs under optimal conditions. Damage to organs is commonly a consequence of flow deprivation and oxygen starvation following the restoration of blood flow and reoxygenation. This is known as ischemia-reperfusion injury(IRI): a complex multifactorial process that causes cell damage. While the oxygen deprivation due to ischemia depletes cell energy, subsequent tissue oxygenation due to reperfusion induces many cascades, from reactive oxygen species production to apoptosis initiation. Autophagy has also been identified in the pathogenesis of IRI, although such alterations and their subsequent functional significance are controversial. Moreover, proteasome activation may be a relevant pathophysiological mechanism. Different strategies have been adopted to limit IRI damage, including the supplementation of commercial preservation media with pharmacological agents or additives. In this review, we focus on novel strategies related to the ubiquitin proteasome system and oxidative stress inhibition, which have been used to minimize damage in liver transplantation.
文摘The terahertz(THz) band lies between microwave and infrared rays in wavelength and consists of non-ionizing radiation. Both domestic and foreign research institutions, including the army, have attached considerable importance to the research and development of THz technology because this radiation exhibits both photon-like and electron-like properties, which grant it considerable application value and potential. With the rapid development of THz technology and related applications, studies of the biological effects of THz radiation have become a major focus in the field of life sciences. Research in this field has only just begun, both at home and abroad. In this paper, research progress with respect to THz radiation, including its biological effects, mechanisms and methods of protection, will be reviewed.
