BACKGROUND Colon cancer cell lines are widely used for research and for the screening of drugs that specifically target the stem cell compartment of colon cancers.It was reported that colon cancer carcinoma specimens ...BACKGROUND Colon cancer cell lines are widely used for research and for the screening of drugs that specifically target the stem cell compartment of colon cancers.It was reported that colon cancer carcinoma specimens contain a subset of leucine-rich repeatcontaining G protein-coupled receptor 5(LGR5)-expressing stem cells,these socalled“tumour-initiating”cells,reminiscent in their properties of the normal intestinal stem cells(ISCs),may explain the apparent heterogeneity of colon cancer cell lines.Also,colon cancer is initiated by aberrant Wnt signaling in ISCs known to express high levels of LGR5.Furthermore,in vivo reports demonstrate the clonal expansion of intestinal adenomas from a single LGR5-expressing cell.AIM To investigate whether colon cancer cell lines contain cancer stem cells and to characterize these putative cancer stem cells.METHODS A portable fluorescent reporter construct based on a conserved fragment of the LGR5 promoter was used to isolate the cell compartments expressing different levels of LGR5 in two widely used colon cancer cell lines(Caco-2 and LoVo).These cells were then characterized according to their proliferation capacity,gene expression signatures of ISC markers,and their tumorigenic properties in vivo and in vitro.RESULTS The data revealed that the LGR5 reporter can be used to identify and isolate a classical intestinal crypt stem cell-like population from the Caco-2,but not from the LoVo,cell lines,in which the cancer stem cell population is more akin to B lymphoma Moloney murine leukemia virus insertion region 1 homolog(+4 crypt)stem cells.This sub-population within Caco-2 cells exhibits an intestinal cancer stem cell gene expression signature and can both self-renew and generate differentiated LGR5 negative progeny.Our data also show that cells expressing high levels of LGR5/enhanced yellow fluorescent protein(EYFP)from this cell line exhibit tumorigenic-like properties in vivo and in vitro.In contrast,cell compartments of LoVo that are expressing high levels of LGR5/EYFP did not show these stem cell-like properties.Thus,cells that exhibit high levels of LGR5/EYFP expression represent the cancer stem cell compartment of Caco-2 colon cancer cells,but not LoVo cells.CONCLUSION Our findings highlight the presence of a spectrum of different ISC-like compartments in different colon cancer cell lines.Their existence is an important consideration for their screening applications and should be taken into account when interpreting drug screening data.We have generated a portable LGR5-reporter that serves as a valuable tool for the identification and isolation of different colon cancer stem cell populations in colon cancer lines.展开更多
OBJECTIVE Takeda G protein-coupled receptor 5(TGR5)is recognized as a promising target for type 2 diabetes and metabolic syndrome;its expression has been demonstrat⁃ed in the brain and is thought to be neuroprotec⁃tiv...OBJECTIVE Takeda G protein-coupled receptor 5(TGR5)is recognized as a promising target for type 2 diabetes and metabolic syndrome;its expression has been demonstrat⁃ed in the brain and is thought to be neuroprotec⁃tive.Here,we hypothesize that dysfunction of central TGR5 may contribute to the pathogene⁃sis of depression.METHODS In well-established chronic social defeat stress(CSDS)and chronic restraint stress(CRS)models of depression,we investigated the functional roles of TGR5 in CA3 pyramidal neurons(PyNs)and underlying mech⁃anisms of the neuronal circuit in depression(for in vivo studies,n=10;for in vitro studies,n=5-10)using fiber photometry;optogenetic,chemoge⁃netic,pharmacological,and molecular profiling techniques;and behavioral tests.RESULTS Both CSDS and CRS most significantly reduced TGR5 expression of hippocampal CA3 PyNs.Genetic overexpression of TGR5 in CA3 PyNs or intra-CA3 infusion of INT-777,a specific agonist,protected against CSDS and CRS,exerting sig⁃nificant antidepressant-like effects that were mediated via CA3 PyN activation.Conversely,genetic knockout or TGR5 knockdown in CA3 facilitated stress-induced depression-like behav⁃iors.Re-expression of TGR5 in CA3 PyNs rather than infusion of INT-777 significantly improved depression-like behaviors in Tgr5 knockout mice exposed to CSDS or CRS.Silencing and stimula⁃tion of CA3 PyNs→somatostatin-GABAergic(gamma-aminobutyric acidergic)neurons of the dorsolateral septum circuit bidirectionally regulat⁃ed depression-like behaviors,and blockade of this circuit abrogated the antidepressant-like effects from TGR5 activation of CA3 PyNs.CON⁃CLUSION TGR5 can regulate depression via CA3 PyNs→somatostatin-GABAergic neurons of dorsolateral septum transmission,suggesting that TGR5 could be a novel target for developing antidepressants.展开更多
BACKGROUND In the heart,aldosterone(Aldo)binds the mineralocorticoid receptor(MR)to exert damaging,adverse remodeling-promoting effects.We recently showed that G protein-coupled receptor-kinase(GRK)-5 blocks the cardi...BACKGROUND In the heart,aldosterone(Aldo)binds the mineralocorticoid receptor(MR)to exert damaging,adverse remodeling-promoting effects.We recently showed that G protein-coupled receptor-kinase(GRK)-5 blocks the cardiac MR by directly phosphorylating it,thereby repressing its transcriptional activity.MR antagonist(MRA)drugs block the cardiac MR reducing morbidity and mortality of advanced human heart failure.Non-steroidal MRAs,such as finerenone,may provide better cardio-protection against Aldo than classic,steroidal MRAs,like spironolactone and eplerenone.AIM To investigate potential differences between finerenone and eplerenone at engaging GRK5-dependent cardiac MR phosphorylation and subsequent blockade.METHODS We used H9c2 cardiomyocytes,which endogenously express the MR and GRK5.RESULTS GRK5 phosphorylates the MR in H9c2 cardiomyocytes in response to finerenone but not to eplerenone.Unlike eplerenone,finerenone alone potently and efficiently suppresses cardiac MR transcriptional activity,thus displaying inverse agonism.GRK5 is necessary for finerenone’s inverse agonism,since GRK5 genetic deletion renders finerenone incapable of blocking cardiac MR transcriptional activity.Eplerenone alone does not fully suppress cardiac MR basal activity regardless of GRK5 expression levels.Finally,GRK5 is necessary for the antiapoptotic,anti-oxidative,and anti-fibrotic effects of both finerenone and eplerenone against Aldo,as well as for the higher efficacy and potency of finerenone at blocking Aldo-induced apoptosis,oxidative stress,and fibrosis.CONCLUSION Finerenone,but not eplerenone,induces GRK5-dependent cardiac MR inhibition,which underlies,at least in part,its higher potency and efficacy,compared to eplerenone,as an MRA in the heart.GRK5 acts as a co-repressor of the cardiac MR and is essential for efficient MR antagonism in the myocardium.展开更多
Objective： To investigate Leucine-rich repeat-containing G protein-coupled receptor 5 （LGR5） expressions in gastric cancer and to evaluate its clinical significance. Methods： LGR5 expression was assessed by immuno...Objective： To investigate Leucine-rich repeat-containing G protein-coupled receptor 5 （LGR5） expressions in gastric cancer and to evaluate its clinical significance. Methods： LGR5 expression was assessed by immunohistochemistry in 257 gastric cancer patients after surgery. The relationships between LGR5 expression and clinicopathological features and patients prognosis were statistically analyzed. Results： The expression of LGR5 was significantly higher in gastric cancers as a cancer stem cell marker than in adjacent normal tissues （P〈0.001）, and more frequently in patients with intestinal type, well-moderate differentiation and stage I and II （P〈0.05）. Although we found gastric cancer patients with LGR5 positive expression had a poorer prognosis, it didn＇t meet statistical significance （P〉0.05）. LGR5 negative expression was significantly related to the favorable overall survival in stage I and II gastric cancer patients （P〈0.05）. Furthermore, patients with high LGR5 expression tended to be more likely to get progression and have poorer progress-free survival （P〈0.05）. Multivariate Cox regression analysis revealed that LGR5 expression was an independent factor of overall survival for the patients with stage I and II gastric cancer （P〈0.05）. Conclusions： Our results show that LGR5 may play an important role in tumorigenesis and progression and would be a powerful marker to predict the prognosis of patients with stage I and II gastric cancer.展开更多
AIM:To investigate the differential expression of leu-cine-rich repeat-containing G protein-coupled receptor5(LGR5)in gastric cancer tissues and its significance related to tumor growth and spread.METHODS:Formalin-fix...AIM:To investigate the differential expression of leu-cine-rich repeat-containing G protein-coupled receptor5(LGR5)in gastric cancer tissues and its significance related to tumor growth and spread.METHODS:Formalin-fixed biopsy specimens of intestinal metaplasia(n=90),dysplasia(n=53),gastric adenocarcinoma(n=180),metastases in lymph nodes and the liver(n=15),and lesion-adjacent normal gastric mucosa(controls;n=145)were obtained for analysis from the Peking University Cancer Hospital’s Department of Pathology and Gastrointestinal Surgery tissue archives(January 2003 to December 2011).The biopsied patients’demographic and clinicopathologic data were retrieved from the hospital’s medical records database.Each specimen was subjected to histopathological typing to classify the tumor node metastasis(TNM)stage and to immunohistochemistry staining to detect the expression of the cancer stem cell marker LGR5.The intergroup differences in LGR5 expression were assessed by Spearman’s rank correlation analysis,and the relationship between LGR5 expression level and the patients’clinicopathological characteristics was evaluated by theχ2test or Fisher’s exact test.RESULTS:Significantly more gastric cancer tissues showed LGR5+staining than normal control tissues(all P<0.01),with immunoreactivity detected in 72.2%(65/90)and 50.9%(27/53)of intestinal metaplasia and dysplasia specimens,respectively,52.8%(95/180)of gastric adenocarcinoma specimens,and 73.3%%(11/15)of metastasis specimens,but 26.9%(39/145)of lesion-adjacent normal gastric mucosa specimens.Comparison of the intensity of LGR5+staining showed an increasing trend that generally followed increasing dedifferentiation and tumor spread(normal tissue<dysplasia,<gastric adenocarcinoma<metastasis;all P<0.001),with the exception of expression level detected in intestinal metaplasia which was higher than that in normal gastric tissues(P<0.001).Moreover,gastric cancer-associated enhanced expression of LGR5 was found to be signifcantly associated with age,tumor differentiation,Lauren type and TNM stage(Ⅰ+ⅡvsⅢ+Ⅳ)(all P<0.05),but not with sex,tumor site,location,size,histology,lymphovascular invasion,depth of invasion,lymph node metastasis or distant metastasis.Patients with LGR5+gastric cancer specimens and without signs of metastasis from the original biopsy experienced more frequent rates of recurrence or metastasis during follow-up than patients with LGR5-specimens(P<0.05).CONCLUSION:Enhanced LGR5 is related to progressive dedifferentiation and metastasis of gastric cancer,indicating the potential of this receptor as an early diagnostic and prognostic biomarker.展开更多
AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood...AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood samples and 38 colonic biopsy samples from 18 patients with histologically proven active UC and 20 healthy control subjects were collected.After preparing tissue microarrays and blood smears HGFR,caudal type homeobox 2(CDX2),prominin-1(CD133) and Musashi-1conventional and double fluorescent immunolabelings were performed.Immunostained samples were digitalized using high-resolution Mirax Desk instrument,and analyzed with the Mirax TMA Module software.For semiquantitative counting of immunopositive lamina propria(LP) cells 5 fields of view were counted at magnification x 200 in each sample core,then mean ± SD were determined.In case of peripheral blood smears,30 fields of view with 100 μm diameter were evaluated in every sample and the number of immunopositive cells(mean ± SD) was determined.Using 337 nm UVA Laser MicroDissection system at least 5000 subepithelial cells from the lamina propria were collected.Gene expression analysis of HGFR,CDX2,CD133,leucine-rich repeat-containing G-protein coupled receptor 5(Lgr5),Musashi-1 and cytokeratin20(CK20) were performed in both laser-microdisscted samples and blood samples by using real time reverse transcription polymerase chain reaction(RT-PCR).RESULTS:By performing conventional and double fluorescent immunolabelings confirmed by RT-PCR,higher number of HGFR(blood:6.7 ± 1.22 vs 38.5 ±3.18;LP:2.25 ± 0.85 vs 9.22 ± 0.65;P < 0.05),CDX2(blood:0 vs 0.94 ± 0.64;LP:0.75 ± 0.55 vs 2.11± 0.75;P < 0.05),CD133(blood:1.1 ± 0.72 vs 8.3± 1.08;LP:11.1 ± 0.85 vs 26.28 ± 1.71;P < 0.05)and Musashi-1(blood and LP:0 vs scattered) positive cells were detected in blood and lamina propria of UC samples as compared to controls.HGFR/CDX2(blood:0 vs 1± 0.59;LP:0.8 ± 0.69 vs 2.06 ± 0.72,P < 0.05)and Musashi-1/CDX2(blood and LP:0 vs scattered) coexpressions were found in blood and lamina propria of UC samples.HGFR/CD133 and CD133/CDX2 coexpressions appeared only in UC lamina propria samples.CDX2,Lgr5 and Musashi-1 expressions in UC blood samples were not accompanied by CK20 mRNA expression.CONCLUSION:In active UC,a portion of circulating HGFR-expressing cells are committed to the epithelial lineage,and may participate in mucosal regeneration by undergoing mesenchymal-to-epithelial transition.展开更多
The process of apoptotic cell death for maintenance of cell homeostasis is now believed to be flexible. To examine the mechanism for this flexibility, the process of programmed cell death is sometimes divided into thr...The process of apoptotic cell death for maintenance of cell homeostasis is now believed to be flexible. To examine the mechanism for this flexibility, the process of programmed cell death is sometimes divided into three phases: initiation, effector and execution. We have demonstrated that apoptotic cells commonly express a de novo synthesized C5a receptor (C5aR), which belongs to the G protein-coupled receptor (GPCR) family. A natural agnostic ligand of the C5aR, C5a, is produced from plasma C5 by C5 convertase in the early phase of acute inflammation. Although it is not realistic, we found that C5a can adjust apoptotic cell lifespan long. We recently have read interesting reports that apoptotic cells can release natural agnostic ligands at the initiation phase and corresponding GPCRs are already expressed on cell surfaces of apoptotic cells. Conversely, we found that apoptotic cells commonly release an alternative antagonistic/agnostic ligand of the de novo synthesized C5aR, ribosomal protein S19 (RP S19) polymer. The RP S19 polymer can adjust apoptotic cell lifespan short. Importantly, the C5a-dependent regulation is limited by the C5aR sensitization, but the RP S19 polymer-dependent regulation is unlimited by the C5aR desensitization. Therefore, we suggested that apoptotic cells commonly release agnostic ligands in the initiation phase that should lengthen intermittently a period of the initiation phase. Next, apoptotic cells commonly release antagonistic/agnostic ligands in the effector phase that should continue shortening a period of the effector phase. In addition, we know that an inherited erythroblastopenia is associated with mutations in the RP S19 gene. However, the roles of RP S19 in the formation of erythroblast-macrophage islands are not clearly understood. We recently have found that a different arm that the RP S19 polymer has connects the de novo synthesized C5aR on erythroblasts and the generally expressed C5aR on macrophages. Therefore, we suggested that apoptotic cells commonly release antagonistic/agnostic ligands in the execution phase that should continue connecting apoptotic cells and macrophages in the execution phase for shortening a period of the execution phase. In this review, we introduce new aspects of the C5aR in apoptotic cells and discuss the effects of the long lifespan of apoptotic cell-like neutrophils on the development of periodontitis.展开更多
Background and aims:Diet-induced obesity and metabolic syndrome can trigger the progression of fatty liver disease to non-alcoholic steatohepatitis and fibrosis,which is a major public health concern.Bile acids regula...Background and aims:Diet-induced obesity and metabolic syndrome can trigger the progression of fatty liver disease to non-alcoholic steatohepatitis and fibrosis,which is a major public health concern.Bile acids regulate metabolic homeostasis and inflammation in the liver and gut via the activation of nuclear farnesoid X receptor(Fxr)and the membrane receptor Takeda G protein-coupled receptor 5(Tgr5).Tgr5 is highly expressed in the gut and skeletal muscle,and in cholangiocytes and Kupffer cells of the liver.Tgr5 is implicated in the mediation of liver and gut inflammation,as well as the maintenance of energy homeostasis.Here,we used a high fat,high fructose,and high sucrose(HFS)diet to determine how bile acid signaling through Tgr5 may regulate metabolism during the progression from fatty liver to non-alcoholic steatohepatitis and fibrosis.Materials and methods:Female C57BL/6J control wild type(WT)and Tgr5 knockout(Tgr5^(-/-))mice were fed HFS(high fat(40%kcal),high fructose,and 20%sucrose water)diet for 20 weeks.Metabolic phe-notypes were characterized through examination of bile acid synthesis pathways,lipid and cholesterol metabolism pathways,and fibrosis and inflammation pathways.Results:Tgr5^(-/-)mice were more glucose intolerant when fed HFS diet,despite gaining the same amount of weight as WT mice.Tgr5^(-/-)mice accumulated significantly more hepatic cholesterol and triglycerides on HFS diet compared to WT mice,and gene expression of lipogenic genes was significantly upregulated.Hepatic cholesterol 7alpha-hydroxylase(Cyp7a1)gene expression was consistently elevated in Tgr5^(-/-)mice,while oxysterol 7alpha-hydroxylase(Cyp7b1),sterol 27-hydroxylase(Cyp27a1),Fxr,and small heterodimer partner(Shp)were downregulated by HFS diet.Surprisingly,hepatic inflammation and fibrosis were also significantly reduced in Tgr5^(-/-)mice fed HFS diet,which may be due to altered se-rotonin signaling in the liver.Conclusions:Tgr5^(-/-)mice may be protected from high fat,high sugar-induced hepatic inflammation and injury due to altered serotonin metabolism.展开更多
基金We thank Professor McGuckin M(MMRI,Brisbane)for providing human colon cancer cell lines(Caco-2,LoVo,and SW480)Dr.Rolfe B(AIBN,Brisbane)for providing mouse NSC-34 cells.
文摘BACKGROUND Colon cancer cell lines are widely used for research and for the screening of drugs that specifically target the stem cell compartment of colon cancers.It was reported that colon cancer carcinoma specimens contain a subset of leucine-rich repeatcontaining G protein-coupled receptor 5(LGR5)-expressing stem cells,these socalled“tumour-initiating”cells,reminiscent in their properties of the normal intestinal stem cells(ISCs),may explain the apparent heterogeneity of colon cancer cell lines.Also,colon cancer is initiated by aberrant Wnt signaling in ISCs known to express high levels of LGR5.Furthermore,in vivo reports demonstrate the clonal expansion of intestinal adenomas from a single LGR5-expressing cell.AIM To investigate whether colon cancer cell lines contain cancer stem cells and to characterize these putative cancer stem cells.METHODS A portable fluorescent reporter construct based on a conserved fragment of the LGR5 promoter was used to isolate the cell compartments expressing different levels of LGR5 in two widely used colon cancer cell lines(Caco-2 and LoVo).These cells were then characterized according to their proliferation capacity,gene expression signatures of ISC markers,and their tumorigenic properties in vivo and in vitro.RESULTS The data revealed that the LGR5 reporter can be used to identify and isolate a classical intestinal crypt stem cell-like population from the Caco-2,but not from the LoVo,cell lines,in which the cancer stem cell population is more akin to B lymphoma Moloney murine leukemia virus insertion region 1 homolog(+4 crypt)stem cells.This sub-population within Caco-2 cells exhibits an intestinal cancer stem cell gene expression signature and can both self-renew and generate differentiated LGR5 negative progeny.Our data also show that cells expressing high levels of LGR5/enhanced yellow fluorescent protein(EYFP)from this cell line exhibit tumorigenic-like properties in vivo and in vitro.In contrast,cell compartments of LoVo that are expressing high levels of LGR5/EYFP did not show these stem cell-like properties.Thus,cells that exhibit high levels of LGR5/EYFP expression represent the cancer stem cell compartment of Caco-2 colon cancer cells,but not LoVo cells.CONCLUSION Our findings highlight the presence of a spectrum of different ISC-like compartments in different colon cancer cell lines.Their existence is an important consideration for their screening applications and should be taken into account when interpreting drug screening data.We have generated a portable LGR5-reporter that serves as a valuable tool for the identification and isolation of different colon cancer stem cell populations in colon cancer lines.
文摘OBJECTIVE Takeda G protein-coupled receptor 5(TGR5)is recognized as a promising target for type 2 diabetes and metabolic syndrome;its expression has been demonstrat⁃ed in the brain and is thought to be neuroprotec⁃tive.Here,we hypothesize that dysfunction of central TGR5 may contribute to the pathogene⁃sis of depression.METHODS In well-established chronic social defeat stress(CSDS)and chronic restraint stress(CRS)models of depression,we investigated the functional roles of TGR5 in CA3 pyramidal neurons(PyNs)and underlying mech⁃anisms of the neuronal circuit in depression(for in vivo studies,n=10;for in vitro studies,n=5-10)using fiber photometry;optogenetic,chemoge⁃netic,pharmacological,and molecular profiling techniques;and behavioral tests.RESULTS Both CSDS and CRS most significantly reduced TGR5 expression of hippocampal CA3 PyNs.Genetic overexpression of TGR5 in CA3 PyNs or intra-CA3 infusion of INT-777,a specific agonist,protected against CSDS and CRS,exerting sig⁃nificant antidepressant-like effects that were mediated via CA3 PyN activation.Conversely,genetic knockout or TGR5 knockdown in CA3 facilitated stress-induced depression-like behav⁃iors.Re-expression of TGR5 in CA3 PyNs rather than infusion of INT-777 significantly improved depression-like behaviors in Tgr5 knockout mice exposed to CSDS or CRS.Silencing and stimula⁃tion of CA3 PyNs→somatostatin-GABAergic(gamma-aminobutyric acidergic)neurons of the dorsolateral septum circuit bidirectionally regulat⁃ed depression-like behaviors,and blockade of this circuit abrogated the antidepressant-like effects from TGR5 activation of CA3 PyNs.CON⁃CLUSION TGR5 can regulate depression via CA3 PyNs→somatostatin-GABAergic neurons of dorsolateral septum transmission,suggesting that TGR5 could be a novel target for developing antidepressants.
文摘BACKGROUND In the heart,aldosterone(Aldo)binds the mineralocorticoid receptor(MR)to exert damaging,adverse remodeling-promoting effects.We recently showed that G protein-coupled receptor-kinase(GRK)-5 blocks the cardiac MR by directly phosphorylating it,thereby repressing its transcriptional activity.MR antagonist(MRA)drugs block the cardiac MR reducing morbidity and mortality of advanced human heart failure.Non-steroidal MRAs,such as finerenone,may provide better cardio-protection against Aldo than classic,steroidal MRAs,like spironolactone and eplerenone.AIM To investigate potential differences between finerenone and eplerenone at engaging GRK5-dependent cardiac MR phosphorylation and subsequent blockade.METHODS We used H9c2 cardiomyocytes,which endogenously express the MR and GRK5.RESULTS GRK5 phosphorylates the MR in H9c2 cardiomyocytes in response to finerenone but not to eplerenone.Unlike eplerenone,finerenone alone potently and efficiently suppresses cardiac MR transcriptional activity,thus displaying inverse agonism.GRK5 is necessary for finerenone’s inverse agonism,since GRK5 genetic deletion renders finerenone incapable of blocking cardiac MR transcriptional activity.Eplerenone alone does not fully suppress cardiac MR basal activity regardless of GRK5 expression levels.Finally,GRK5 is necessary for the antiapoptotic,anti-oxidative,and anti-fibrotic effects of both finerenone and eplerenone against Aldo,as well as for the higher efficacy and potency of finerenone at blocking Aldo-induced apoptosis,oxidative stress,and fibrosis.CONCLUSION Finerenone,but not eplerenone,induces GRK5-dependent cardiac MR inhibition,which underlies,at least in part,its higher potency and efficacy,compared to eplerenone,as an MRA in the heart.GRK5 acts as a co-repressor of the cardiac MR and is essential for efficient MR antagonism in the myocardium.
文摘Objective： To investigate Leucine-rich repeat-containing G protein-coupled receptor 5 （LGR5） expressions in gastric cancer and to evaluate its clinical significance. Methods： LGR5 expression was assessed by immunohistochemistry in 257 gastric cancer patients after surgery. The relationships between LGR5 expression and clinicopathological features and patients prognosis were statistically analyzed. Results： The expression of LGR5 was significantly higher in gastric cancers as a cancer stem cell marker than in adjacent normal tissues （P〈0.001）, and more frequently in patients with intestinal type, well-moderate differentiation and stage I and II （P〈0.05）. Although we found gastric cancer patients with LGR5 positive expression had a poorer prognosis, it didn＇t meet statistical significance （P〉0.05）. LGR5 negative expression was significantly related to the favorable overall survival in stage I and II gastric cancer patients （P〈0.05）. Furthermore, patients with high LGR5 expression tended to be more likely to get progression and have poorer progress-free survival （P〈0.05）. Multivariate Cox regression analysis revealed that LGR5 expression was an independent factor of overall survival for the patients with stage I and II gastric cancer （P〈0.05）. Conclusions： Our results show that LGR5 may play an important role in tumorigenesis and progression and would be a powerful marker to predict the prognosis of patients with stage I and II gastric cancer.
基金Supported by A grant from the Beijing Municipal Science and Technology Commission’s NOVA Program,No.2009BG-02Beijing Municipal Health System Special funds of High-Level Medical Personnel Construction,No.2013-3-082
文摘AIM:To investigate the differential expression of leu-cine-rich repeat-containing G protein-coupled receptor5(LGR5)in gastric cancer tissues and its significance related to tumor growth and spread.METHODS:Formalin-fixed biopsy specimens of intestinal metaplasia(n=90),dysplasia(n=53),gastric adenocarcinoma(n=180),metastases in lymph nodes and the liver(n=15),and lesion-adjacent normal gastric mucosa(controls;n=145)were obtained for analysis from the Peking University Cancer Hospital’s Department of Pathology and Gastrointestinal Surgery tissue archives(January 2003 to December 2011).The biopsied patients’demographic and clinicopathologic data were retrieved from the hospital’s medical records database.Each specimen was subjected to histopathological typing to classify the tumor node metastasis(TNM)stage and to immunohistochemistry staining to detect the expression of the cancer stem cell marker LGR5.The intergroup differences in LGR5 expression were assessed by Spearman’s rank correlation analysis,and the relationship between LGR5 expression level and the patients’clinicopathological characteristics was evaluated by theχ2test or Fisher’s exact test.RESULTS:Significantly more gastric cancer tissues showed LGR5+staining than normal control tissues(all P<0.01),with immunoreactivity detected in 72.2%(65/90)and 50.9%(27/53)of intestinal metaplasia and dysplasia specimens,respectively,52.8%(95/180)of gastric adenocarcinoma specimens,and 73.3%%(11/15)of metastasis specimens,but 26.9%(39/145)of lesion-adjacent normal gastric mucosa specimens.Comparison of the intensity of LGR5+staining showed an increasing trend that generally followed increasing dedifferentiation and tumor spread(normal tissue<dysplasia,<gastric adenocarcinoma<metastasis;all P<0.001),with the exception of expression level detected in intestinal metaplasia which was higher than that in normal gastric tissues(P<0.001).Moreover,gastric cancer-associated enhanced expression of LGR5 was found to be signifcantly associated with age,tumor differentiation,Lauren type and TNM stage(Ⅰ+ⅡvsⅢ+Ⅳ)(all P<0.05),but not with sex,tumor site,location,size,histology,lymphovascular invasion,depth of invasion,lymph node metastasis or distant metastasis.Patients with LGR5+gastric cancer specimens and without signs of metastasis from the original biopsy experienced more frequent rates of recurrence or metastasis during follow-up than patients with LGR5-specimens(P<0.05).CONCLUSION:Enhanced LGR5 is related to progressive dedifferentiation and metastasis of gastric cancer,indicating the potential of this receptor as an early diagnostic and prognostic biomarker.
基金Cell Analysis Laboratory, 2nd Department of Internal Medicine, and the 1st Department of Pathology and Experimental Oncology, Semmelweis University for their technical support
文摘AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood samples and 38 colonic biopsy samples from 18 patients with histologically proven active UC and 20 healthy control subjects were collected.After preparing tissue microarrays and blood smears HGFR,caudal type homeobox 2(CDX2),prominin-1(CD133) and Musashi-1conventional and double fluorescent immunolabelings were performed.Immunostained samples were digitalized using high-resolution Mirax Desk instrument,and analyzed with the Mirax TMA Module software.For semiquantitative counting of immunopositive lamina propria(LP) cells 5 fields of view were counted at magnification x 200 in each sample core,then mean ± SD were determined.In case of peripheral blood smears,30 fields of view with 100 μm diameter were evaluated in every sample and the number of immunopositive cells(mean ± SD) was determined.Using 337 nm UVA Laser MicroDissection system at least 5000 subepithelial cells from the lamina propria were collected.Gene expression analysis of HGFR,CDX2,CD133,leucine-rich repeat-containing G-protein coupled receptor 5(Lgr5),Musashi-1 and cytokeratin20(CK20) were performed in both laser-microdisscted samples and blood samples by using real time reverse transcription polymerase chain reaction(RT-PCR).RESULTS:By performing conventional and double fluorescent immunolabelings confirmed by RT-PCR,higher number of HGFR(blood:6.7 ± 1.22 vs 38.5 ±3.18;LP:2.25 ± 0.85 vs 9.22 ± 0.65;P < 0.05),CDX2(blood:0 vs 0.94 ± 0.64;LP:0.75 ± 0.55 vs 2.11± 0.75;P < 0.05),CD133(blood:1.1 ± 0.72 vs 8.3± 1.08;LP:11.1 ± 0.85 vs 26.28 ± 1.71;P < 0.05)and Musashi-1(blood and LP:0 vs scattered) positive cells were detected in blood and lamina propria of UC samples as compared to controls.HGFR/CDX2(blood:0 vs 1± 0.59;LP:0.8 ± 0.69 vs 2.06 ± 0.72,P < 0.05)and Musashi-1/CDX2(blood and LP:0 vs scattered) coexpressions were found in blood and lamina propria of UC samples.HGFR/CD133 and CD133/CDX2 coexpressions appeared only in UC lamina propria samples.CDX2,Lgr5 and Musashi-1 expressions in UC blood samples were not accompanied by CK20 mRNA expression.CONCLUSION:In active UC,a portion of circulating HGFR-expressing cells are committed to the epithelial lineage,and may participate in mucosal regeneration by undergoing mesenchymal-to-epithelial transition.
文摘The process of apoptotic cell death for maintenance of cell homeostasis is now believed to be flexible. To examine the mechanism for this flexibility, the process of programmed cell death is sometimes divided into three phases: initiation, effector and execution. We have demonstrated that apoptotic cells commonly express a de novo synthesized C5a receptor (C5aR), which belongs to the G protein-coupled receptor (GPCR) family. A natural agnostic ligand of the C5aR, C5a, is produced from plasma C5 by C5 convertase in the early phase of acute inflammation. Although it is not realistic, we found that C5a can adjust apoptotic cell lifespan long. We recently have read interesting reports that apoptotic cells can release natural agnostic ligands at the initiation phase and corresponding GPCRs are already expressed on cell surfaces of apoptotic cells. Conversely, we found that apoptotic cells commonly release an alternative antagonistic/agnostic ligand of the de novo synthesized C5aR, ribosomal protein S19 (RP S19) polymer. The RP S19 polymer can adjust apoptotic cell lifespan short. Importantly, the C5a-dependent regulation is limited by the C5aR sensitization, but the RP S19 polymer-dependent regulation is unlimited by the C5aR desensitization. Therefore, we suggested that apoptotic cells commonly release agnostic ligands in the initiation phase that should lengthen intermittently a period of the initiation phase. Next, apoptotic cells commonly release antagonistic/agnostic ligands in the effector phase that should continue shortening a period of the effector phase. In addition, we know that an inherited erythroblastopenia is associated with mutations in the RP S19 gene. However, the roles of RP S19 in the formation of erythroblast-macrophage islands are not clearly understood. We recently have found that a different arm that the RP S19 polymer has connects the de novo synthesized C5aR on erythroblasts and the generally expressed C5aR on macrophages. Therefore, we suggested that apoptotic cells commonly release antagonistic/agnostic ligands in the execution phase that should continue connecting apoptotic cells and macrophages in the execution phase for shortening a period of the execution phase. In this review, we introduce new aspects of the C5aR in apoptotic cells and discuss the effects of the long lifespan of apoptotic cell-like neutrophils on the development of periodontitis.
基金This work was supported by the USA National Institutes of Health(NIH)(AA015951,DK044442,and DK058379).
文摘Background and aims:Diet-induced obesity and metabolic syndrome can trigger the progression of fatty liver disease to non-alcoholic steatohepatitis and fibrosis,which is a major public health concern.Bile acids regulate metabolic homeostasis and inflammation in the liver and gut via the activation of nuclear farnesoid X receptor(Fxr)and the membrane receptor Takeda G protein-coupled receptor 5(Tgr5).Tgr5 is highly expressed in the gut and skeletal muscle,and in cholangiocytes and Kupffer cells of the liver.Tgr5 is implicated in the mediation of liver and gut inflammation,as well as the maintenance of energy homeostasis.Here,we used a high fat,high fructose,and high sucrose(HFS)diet to determine how bile acid signaling through Tgr5 may regulate metabolism during the progression from fatty liver to non-alcoholic steatohepatitis and fibrosis.Materials and methods:Female C57BL/6J control wild type(WT)and Tgr5 knockout(Tgr5^(-/-))mice were fed HFS(high fat(40%kcal),high fructose,and 20%sucrose water)diet for 20 weeks.Metabolic phe-notypes were characterized through examination of bile acid synthesis pathways,lipid and cholesterol metabolism pathways,and fibrosis and inflammation pathways.Results:Tgr5^(-/-)mice were more glucose intolerant when fed HFS diet,despite gaining the same amount of weight as WT mice.Tgr5^(-/-)mice accumulated significantly more hepatic cholesterol and triglycerides on HFS diet compared to WT mice,and gene expression of lipogenic genes was significantly upregulated.Hepatic cholesterol 7alpha-hydroxylase(Cyp7a1)gene expression was consistently elevated in Tgr5^(-/-)mice,while oxysterol 7alpha-hydroxylase(Cyp7b1),sterol 27-hydroxylase(Cyp27a1),Fxr,and small heterodimer partner(Shp)were downregulated by HFS diet.Surprisingly,hepatic inflammation and fibrosis were also significantly reduced in Tgr5^(-/-)mice fed HFS diet,which may be due to altered se-rotonin signaling in the liver.Conclusions:Tgr5^(-/-)mice may be protected from high fat,high sugar-induced hepatic inflammation and injury due to altered serotonin metabolism.
