BACKGROUND Parathyroid hormone-related peptide(PTHrP)plays a key role in the development and progression of many tumors.We found that in colorectal cancer(CRC)HCT116 cells,the binding of PTHrP to its receptor PTHR typ...BACKGROUND Parathyroid hormone-related peptide(PTHrP)plays a key role in the development and progression of many tumors.We found that in colorectal cancer(CRC)HCT116 cells,the binding of PTHrP to its receptor PTHR type 1(PTHR1)activates events associated with an aggressive phenotype.In HCT116 cell xenografts,PTHrP modulates the expression of molecular markers linked to tumor progression.Empirical evidence suggests that the Met receptor is involved in the development and evolution of CRC.Based on these data,we hypothesized that the signaling pathway trigged by PTHrP could be involved in the transactivation of Met and consequently in the aggressive behavior of CRC cells.AIM To elucidate the relationship among PTHR1,PTHrP,and Met in CRC models.METHODS For in vitro assays,HCT116 and Caco-2 cells derived from human CRC were incubated in the absence or presence of PTHrP(1-34)(10-8 M).Where indicated,cells were pre-incubated with specific kinase inhibitors or dimethylsulfoxide,the vehicle of the inhibitors.The protein levels were evaluated by Western blot technique.Real-time polymerase chain reaction(RT-qPCR)was carried out to determine the changes in gene expression.Wound healing assay and morpho logical monitoring were performed to evaluate cell migration and changes related to the epithelialmesenchymal transition(EMT),respectively.The number of viable HCT116 cells was counted by trypan blue dye exclusion test to evaluate the effects of irinotecan(CPT-11),oxaliplatin(OXA),or doxorubicin(DOXO)with or without PTHrP.For in vivo tests,HCT116 cell xenografts on 6-wk-old male N:NIH(S)_nu mice received daily intratumoral injections of PTHrP(40μg/kg)in 100μL phosphate-buffered saline(PBS)or the vehicle(PBS)as a control during 20 d.Humanitarian slaughter was carried out and the tumors were removed,weighed,and fixed in a 4%formaldehyde solution for subsequent treatment by immunoassays.To evaluate the expression of molecular markers in human tumor samples,we studied 23 specimens obtained from CRC patients which were treated at the Hospital Interzonal de Graves y Agudos Dr.JoséPenna(Bahía Blanca,Buenos Aires,Argentina)and the Hospital Provincial de Neuquén(Neuquén,Neuquén,Argentina)from January 1990 to December 2007.Seven cases with normal colorectal tissues were assigned to the control group.Tumor tissue samples and clinical histories of patients were analyzed.Paraffin-embedded blocks from primary tumors were reviewed by hematoxylin-eosin staining technique;subsequently,representative histological samples were selected from each patient.From each paraffin block,tumor sections were stained for immunohistochemical detection.The statistical significance of differences was analyzed using proper statistical analysis.The results were considered statistically significant at P<0.05.RESULTS By Western blot analysis and using total Met antibody,we found that PTHrP regulated Met expression in HCT116 cells but not in Caco-2 cells.In HCT116 cells,Met protein levels increased at 30 min(P<0.01)and at 20 h(P<0.01)whereas the levels diminished at 3 min(P<0.05),10 min(P<0.01),and 1 h to 5 h(P<0.01)of PTHrP treatment.Using an active Met antibody,we found that where the protein levels of total Met decreased(3 min,10 min,and 60 min of PTHrP exposure),the status of phosphorylated/activated Met increased(P<0.01)at the same time,suggesting that Met undergoes proteasomal degradation after its phosphorylation/activation by PTHrP.The increment of its protein level after these decreases(at 30 min and 20 h)suggests a modulation of Met expression by PTHrP in order to improve Met levels and this idea is supported by our observation that the cytokine increased Met mRNA levels at least at 15 min in HCT116 cells as revealed by RT-qPCR analysis(P<0.05).We then proceeded to evaluate the signaling pathways that mediate the phosphorylation/activation of Met induced by PTHrP in HCT116 cells.By Western blot technique,we observed that PP1,a specific inhibitor of the activation of the protooncogene protein tyrosine kinase Src,blocked the effect of PTHrP on Met phosphorylation(P<0.05).Furthermore,the selective inhibition of the ERK 1/2 mitogen-activated protein kinase(ERK 1/2 MAPK)using PD98059 and the p38 MAPK using SB203580 diminished the effect of PTHrP on Met phosphorylation/activation(P<0.05).Using SU11274,the specific inhibitor of Met activation,and trypan blue dye exclusion test,Western blot,wound healing assay,and morphological analysis with a microscope,we observed the reversal of cell events induced by PTHrP such as cell proliferation(P<0.05),migration(P<0.05),and the EMT program(P<0.01)in HCT116 cells.Also,PTHrP favored the chemoresistance to CPT-11(P<0.001),OXA(P<0.01),and DOXO(P<0.01)through the Met pathway.Taken together,these findings suggest that Met activated by PTHrP participates in events associated with the aggressive phenotype of CRC cells.By immunohistochemical analysis,we found that PTHrP in HCT116 cell xenografts enhanced the protein expression of Met(0.190±0.014)compared to tumors from control mice(0.110±0.012;P<0.05)and of its own receptor(2.27±0.20)compared to tumors from control mice(1.98±0.14;P<0.01).Finally,assuming that the changes in the expression of PTHrP and its receptor are directly correlated,we investigated the expression of both Met and PTHR1 in biopsies of CRC patients by immunohistochemical analysis.Comparing histologically differentiated tumors with respect to those less differentiated,we found that the labeling intensity for Met and PTHR1 increased and diminished in a gradual manner,respectively(P<0.05).CONCLUSION PTHrP acts through the Met pathway in CRC cells and regulates Met expression in a CRC animal model.More basic and clinical studies are needed to further evaluate the PTHrP/Met relationship.展开更多
Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reve...Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reverse transcription PCR(RT-PCR)was used to detect the expressions of ERα,ERβ and c-met proto-oncogene mRNA in 30 samples of endometrial carcinoma and 11 samples of normal endometrium.Results The expression of ERα in endometrial carcinoma(0.70±0.40)was significantly reduced in comparison to that in normal endometrium(1.14±0.56,P<0.05).A similar finding was made for the expression of ERβ in carcinoma(0.24±0.18)versus normal tissues(0.48±0.20,P<0.05).In contrast,c-met mRNA expression was increased in endometrial carcinoma(1.45±0.72)compared to that in normal endometrium(0.42±0.31,P<0.01).A decrease tendency of the expression of ERα was also found from Stage Ⅰ(0.82±0.41)to a more severe Stag Ⅱ-Ⅲ of endometrial carcinoma(0.42±0.17,P<0.05).The analysis of ERα and ERβ mRNA revealed a decrease tendency from shallow to deep invasion of the uterine muscles(P<0.05).We found that the expressions of ERα and ERβ were negatively correlated with c-met proto-oncogene with a coefficient correlation of-0.63(P<0.01)and-0.32(P<0.05),respectively.Conclusion ERα and ERβ are both involved in mutagenic action of carcinogen.C-met proto-oncogene plays an important role in the carcinogenesis and development of endometrial carcinoma.C-met and ER expressions show a negative correlation in the development of endometrial carcinoma.展开更多
BACKGROUND: Ron receptor tyrosine kinase signaling in macrophages, including Kupffer cells and alveolar macrophages,suppresses endotoxin-induced proinflammatory cytokine/chemokine production. Further, we have also ide...BACKGROUND: Ron receptor tyrosine kinase signaling in macrophages, including Kupffer cells and alveolar macrophages,suppresses endotoxin-induced proinflammatory cytokine/chemokine production. Further, we have also identified genes from Ron replete and Ron deplete livers that were differentially expressed during the progression of liver inflammation associated with acute liver failure in mice by microarray analyses.While important genes and signaling pathways have been identified downstream of Ron signaling during progression of inflammation by this approach, the precise role that Ron receptor plays in regulating the transcriptional landscape in macrophages, and particular in isolated Kupffer cells, has still not been investigated.METHODS: Kupffer cells were isolated from wild-type(TK+/+)and Ron tyrosine kinase deficient(TK-/-) mice. Ex vivo, the cells were treated with lipopolysaccharide(LPS) in the presence or absence of the Ron ligand, hepatocyte growth factor-like protein(HGFL). Microarray and qRT-PCR analyses were utilized to identify alterations in gene expression between genotypes.RESULTS: Microarray analyses identified genes expressed differentially in TK+/+ and TK-/- Kupffer cells basally as well as after HGFL and LPS treatment. Interestingly, our studies identified Mefv, a gene that codes for the anti-inflammatory protein pyrin, as an HGFL-stimulated Ron-dependent gene.Moreover, lipocalin 2, a proinflammatory gene, which is induced by LPS, was significantly suppressed by HGFL treatment.Microarray results were validated by qRT-PCR studies on Kupffer cells treated with LPS and HGFL.CONCLUSION: The studies herein suggest a novel mechanism whereby HGFL-induced Ron receptor activation promotes the expression of anti-inflammatory genes while inhibiting genes involved in inflammation with a net effect of diminished inflammation in macrophages.展开更多
目的:探讨肝细胞生长因子(H G F)及其受体(C-M et)与子宫内膜异位症发病机制的关系。方法:采用链霉素抗生物素蛋白-过氧化物酶(S-P)法检测45例(增生期20例,分泌期25例)盆腔子宫内膜异位症及30例(增生期12例,分泌期18例非子宫内膜异位症...目的:探讨肝细胞生长因子(H G F)及其受体(C-M et)与子宫内膜异位症发病机制的关系。方法:采用链霉素抗生物素蛋白-过氧化物酶(S-P)法检测45例(增生期20例,分泌期25例)盆腔子宫内膜异位症及30例(增生期12例,分泌期18例非子宫内膜异位症妇女的在位子宫内膜的H G F与C-M et的免疫表达水平。结果:(1)盆腔子)宫内膜异位症的在位子宫内膜的H G F、C-M et表达水平显著增高P=0.006,P=0.001)。(2)H G F与C-M et呈正相(关(异位症及对照组r均为0.945)。(3)H G F与C-M et均随月经发生周期性变化(分泌期高于增生期,对照组H G F、C-M et分别为P=0.015、P=0.023;内异症组H G F、C-M et分别为P=0.003、P=0.015)。结论:类似肿瘤转移和浸润机制,H G F/C-M et系统可能参与了子宫内膜异位症的发病。展开更多
BACKGROUND:Prior experimentation has shown that loss of the tyrosine kinase(TK) signaling domain of the Ron receptor leads to marked hepatocyte protection in a model of lipopolysaccharideinduced acute liver failure(AL...BACKGROUND:Prior experimentation has shown that loss of the tyrosine kinase(TK) signaling domain of the Ron receptor leads to marked hepatocyte protection in a model of lipopolysaccharideinduced acute liver failure(ALF) in D-galactosamine(GalN)sensitized mice.The aim of this study was to identify the role of Ron in the regulation of hepatic gene expression.METHODS:Microarray analyses were performed on liver RNA isolated sequentially from wild-type(WT) and TK-/mice during the progression of ALF.Gene array data were validated using Western and immunohistochemistry analyses as well as with ex vivo culture systems.RESULTS:At baseline,101 genes were differentially expressed between WT and TK-/-livers,which regulate processes involved in hypoxia,proliferation,apoptosis and metabolism.One hour after ALF induction,WT livers exhibited increased cytokine expression compared to TK-/-livers,and after 4 hours,an induction of suppressor of cytokine signaling(SOCS) genes as well as JAK-STAT pathway activation were prominent in TK-/livers compared to controls.CONCLUSION:Our studies suggest a novel hepato-protective mechanism in Ron TK-/-mice wherein increased and sustained SOCS production and JAK-STAT activation in the hepatocyte may inhibit the destructive proinflammatory milieu and promote survival factors which blunt hepatic death and the ensuing development of ALF.展开更多
基金Supported by the Agencia Nacional de Promoción Científica y TecnológicaNo. PICT-2013-1441+8 种基金Consejo Nacional de Investigaciones Científicas y TécnicasNo. PIP11220150100350Instituto Nacional del Cáncer Asistencia Financiera ⅡRESOL 493/14, No. 2002-4395-14-1Instituto Nacional del Cáncer Asistencia Financiera Ⅲ-2016-2017, RESOL-2016-1006-E-APN-MSNo. 2002-3862-16-1 CANCERUniversidad Nacional del SurNo. PGI:24/B230 and No. PGI:24/B303Fundación Alberto J. Roemmers of Argentina
文摘BACKGROUND Parathyroid hormone-related peptide(PTHrP)plays a key role in the development and progression of many tumors.We found that in colorectal cancer(CRC)HCT116 cells,the binding of PTHrP to its receptor PTHR type 1(PTHR1)activates events associated with an aggressive phenotype.In HCT116 cell xenografts,PTHrP modulates the expression of molecular markers linked to tumor progression.Empirical evidence suggests that the Met receptor is involved in the development and evolution of CRC.Based on these data,we hypothesized that the signaling pathway trigged by PTHrP could be involved in the transactivation of Met and consequently in the aggressive behavior of CRC cells.AIM To elucidate the relationship among PTHR1,PTHrP,and Met in CRC models.METHODS For in vitro assays,HCT116 and Caco-2 cells derived from human CRC were incubated in the absence or presence of PTHrP(1-34)(10-8 M).Where indicated,cells were pre-incubated with specific kinase inhibitors or dimethylsulfoxide,the vehicle of the inhibitors.The protein levels were evaluated by Western blot technique.Real-time polymerase chain reaction(RT-qPCR)was carried out to determine the changes in gene expression.Wound healing assay and morpho logical monitoring were performed to evaluate cell migration and changes related to the epithelialmesenchymal transition(EMT),respectively.The number of viable HCT116 cells was counted by trypan blue dye exclusion test to evaluate the effects of irinotecan(CPT-11),oxaliplatin(OXA),or doxorubicin(DOXO)with or without PTHrP.For in vivo tests,HCT116 cell xenografts on 6-wk-old male N:NIH(S)_nu mice received daily intratumoral injections of PTHrP(40μg/kg)in 100μL phosphate-buffered saline(PBS)or the vehicle(PBS)as a control during 20 d.Humanitarian slaughter was carried out and the tumors were removed,weighed,and fixed in a 4%formaldehyde solution for subsequent treatment by immunoassays.To evaluate the expression of molecular markers in human tumor samples,we studied 23 specimens obtained from CRC patients which were treated at the Hospital Interzonal de Graves y Agudos Dr.JoséPenna(Bahía Blanca,Buenos Aires,Argentina)and the Hospital Provincial de Neuquén(Neuquén,Neuquén,Argentina)from January 1990 to December 2007.Seven cases with normal colorectal tissues were assigned to the control group.Tumor tissue samples and clinical histories of patients were analyzed.Paraffin-embedded blocks from primary tumors were reviewed by hematoxylin-eosin staining technique;subsequently,representative histological samples were selected from each patient.From each paraffin block,tumor sections were stained for immunohistochemical detection.The statistical significance of differences was analyzed using proper statistical analysis.The results were considered statistically significant at P<0.05.RESULTS By Western blot analysis and using total Met antibody,we found that PTHrP regulated Met expression in HCT116 cells but not in Caco-2 cells.In HCT116 cells,Met protein levels increased at 30 min(P<0.01)and at 20 h(P<0.01)whereas the levels diminished at 3 min(P<0.05),10 min(P<0.01),and 1 h to 5 h(P<0.01)of PTHrP treatment.Using an active Met antibody,we found that where the protein levels of total Met decreased(3 min,10 min,and 60 min of PTHrP exposure),the status of phosphorylated/activated Met increased(P<0.01)at the same time,suggesting that Met undergoes proteasomal degradation after its phosphorylation/activation by PTHrP.The increment of its protein level after these decreases(at 30 min and 20 h)suggests a modulation of Met expression by PTHrP in order to improve Met levels and this idea is supported by our observation that the cytokine increased Met mRNA levels at least at 15 min in HCT116 cells as revealed by RT-qPCR analysis(P<0.05).We then proceeded to evaluate the signaling pathways that mediate the phosphorylation/activation of Met induced by PTHrP in HCT116 cells.By Western blot technique,we observed that PP1,a specific inhibitor of the activation of the protooncogene protein tyrosine kinase Src,blocked the effect of PTHrP on Met phosphorylation(P<0.05).Furthermore,the selective inhibition of the ERK 1/2 mitogen-activated protein kinase(ERK 1/2 MAPK)using PD98059 and the p38 MAPK using SB203580 diminished the effect of PTHrP on Met phosphorylation/activation(P<0.05).Using SU11274,the specific inhibitor of Met activation,and trypan blue dye exclusion test,Western blot,wound healing assay,and morphological analysis with a microscope,we observed the reversal of cell events induced by PTHrP such as cell proliferation(P<0.05),migration(P<0.05),and the EMT program(P<0.01)in HCT116 cells.Also,PTHrP favored the chemoresistance to CPT-11(P<0.001),OXA(P<0.01),and DOXO(P<0.01)through the Met pathway.Taken together,these findings suggest that Met activated by PTHrP participates in events associated with the aggressive phenotype of CRC cells.By immunohistochemical analysis,we found that PTHrP in HCT116 cell xenografts enhanced the protein expression of Met(0.190±0.014)compared to tumors from control mice(0.110±0.012;P<0.05)and of its own receptor(2.27±0.20)compared to tumors from control mice(1.98±0.14;P<0.01).Finally,assuming that the changes in the expression of PTHrP and its receptor are directly correlated,we investigated the expression of both Met and PTHR1 in biopsies of CRC patients by immunohistochemical analysis.Comparing histologically differentiated tumors with respect to those less differentiated,we found that the labeling intensity for Met and PTHR1 increased and diminished in a gradual manner,respectively(P<0.05).CONCLUSION PTHrP acts through the Met pathway in CRC cells and regulates Met expression in a CRC animal model.More basic and clinical studies are needed to further evaluate the PTHrP/Met relationship.
文摘Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reverse transcription PCR(RT-PCR)was used to detect the expressions of ERα,ERβ and c-met proto-oncogene mRNA in 30 samples of endometrial carcinoma and 11 samples of normal endometrium.Results The expression of ERα in endometrial carcinoma(0.70±0.40)was significantly reduced in comparison to that in normal endometrium(1.14±0.56,P<0.05).A similar finding was made for the expression of ERβ in carcinoma(0.24±0.18)versus normal tissues(0.48±0.20,P<0.05).In contrast,c-met mRNA expression was increased in endometrial carcinoma(1.45±0.72)compared to that in normal endometrium(0.42±0.31,P<0.01).A decrease tendency of the expression of ERα was also found from Stage Ⅰ(0.82±0.41)to a more severe Stag Ⅱ-Ⅲ of endometrial carcinoma(0.42±0.17,P<0.05).The analysis of ERα and ERβ mRNA revealed a decrease tendency from shallow to deep invasion of the uterine muscles(P<0.05).We found that the expressions of ERα and ERβ were negatively correlated with c-met proto-oncogene with a coefficient correlation of-0.63(P<0.01)and-0.32(P<0.05),respectively.Conclusion ERα and ERβ are both involved in mutagenic action of carcinogen.C-met proto-oncogene plays an important role in the carcinogenesis and development of endometrial carcinoma.C-met and ER expressions show a negative correlation in the development of endometrial carcinoma.
基金supported in part by grants from the Public Health Services Grants CA125379NIH P30 DK078392 from the National Institutes of Health,Veteran's Administration VA1001BX00080312POST12040055 from the American Heart Association Great Rivers Affiliate
文摘BACKGROUND: Ron receptor tyrosine kinase signaling in macrophages, including Kupffer cells and alveolar macrophages,suppresses endotoxin-induced proinflammatory cytokine/chemokine production. Further, we have also identified genes from Ron replete and Ron deplete livers that were differentially expressed during the progression of liver inflammation associated with acute liver failure in mice by microarray analyses.While important genes and signaling pathways have been identified downstream of Ron signaling during progression of inflammation by this approach, the precise role that Ron receptor plays in regulating the transcriptional landscape in macrophages, and particular in isolated Kupffer cells, has still not been investigated.METHODS: Kupffer cells were isolated from wild-type(TK+/+)and Ron tyrosine kinase deficient(TK-/-) mice. Ex vivo, the cells were treated with lipopolysaccharide(LPS) in the presence or absence of the Ron ligand, hepatocyte growth factor-like protein(HGFL). Microarray and qRT-PCR analyses were utilized to identify alterations in gene expression between genotypes.RESULTS: Microarray analyses identified genes expressed differentially in TK+/+ and TK-/- Kupffer cells basally as well as after HGFL and LPS treatment. Interestingly, our studies identified Mefv, a gene that codes for the anti-inflammatory protein pyrin, as an HGFL-stimulated Ron-dependent gene.Moreover, lipocalin 2, a proinflammatory gene, which is induced by LPS, was significantly suppressed by HGFL treatment.Microarray results were validated by qRT-PCR studies on Kupffer cells treated with LPS and HGFL.CONCLUSION: The studies herein suggest a novel mechanism whereby HGFL-induced Ron receptor activation promotes the expression of anti-inflammatory genes while inhibiting genes involved in inflammation with a net effect of diminished inflammation in macrophages.
文摘目的:探讨肝细胞生长因子(H G F)及其受体(C-M et)与子宫内膜异位症发病机制的关系。方法:采用链霉素抗生物素蛋白-过氧化物酶(S-P)法检测45例(增生期20例,分泌期25例)盆腔子宫内膜异位症及30例(增生期12例,分泌期18例非子宫内膜异位症妇女的在位子宫内膜的H G F与C-M et的免疫表达水平。结果:(1)盆腔子)宫内膜异位症的在位子宫内膜的H G F、C-M et表达水平显著增高P=0.006,P=0.001)。(2)H G F与C-M et呈正相(关(异位症及对照组r均为0.945)。(3)H G F与C-M et均随月经发生周期性变化(分泌期高于增生期,对照组H G F、C-M et分别为P=0.015、P=0.023;内异症组H G F、C-M et分别为P=0.003、P=0.015)。结论:类似肿瘤转移和浸润机制,H G F/C-M et系统可能参与了子宫内膜异位症的发病。
基金supported by grants from the Public Health Services DK-73552 (WSE)the Digestive Diseases Research Development Center DK-064403 (WSE and LMA)from the National Institutes of Healthby grant project #8950(WSE) from Shriner's Hospital for Children
文摘BACKGROUND:Prior experimentation has shown that loss of the tyrosine kinase(TK) signaling domain of the Ron receptor leads to marked hepatocyte protection in a model of lipopolysaccharideinduced acute liver failure(ALF) in D-galactosamine(GalN)sensitized mice.The aim of this study was to identify the role of Ron in the regulation of hepatic gene expression.METHODS:Microarray analyses were performed on liver RNA isolated sequentially from wild-type(WT) and TK-/mice during the progression of ALF.Gene array data were validated using Western and immunohistochemistry analyses as well as with ex vivo culture systems.RESULTS:At baseline,101 genes were differentially expressed between WT and TK-/-livers,which regulate processes involved in hypoxia,proliferation,apoptosis and metabolism.One hour after ALF induction,WT livers exhibited increased cytokine expression compared to TK-/-livers,and after 4 hours,an induction of suppressor of cytokine signaling(SOCS) genes as well as JAK-STAT pathway activation were prominent in TK-/livers compared to controls.CONCLUSION:Our studies suggest a novel hepato-protective mechanism in Ron TK-/-mice wherein increased and sustained SOCS production and JAK-STAT activation in the hepatocyte may inhibit the destructive proinflammatory milieu and promote survival factors which blunt hepatic death and the ensuing development of ALF.
