The RON receptor tyrosine kinase, a member of the MET proto-oncogene family, is a pathogenic factor im- plicated in tumor malignancy. Specifically, aberrations in RON signaling result in increased cancer cell growth, ...The RON receptor tyrosine kinase, a member of the MET proto-oncogene family, is a pathogenic factor im- plicated in tumor malignancy. Specifically, aberrations in RON signaling result in increased cancer cell growth, survival, invasion, angiogenesis, and drug resistance. Biochemical events such as ligand binding, receptor over- expression, generation of structure-defected variants, and point mutations in the kinase domain contribute to RON signaling activation. Recently, functional crosstalk between RON and signaling proteins such as MET and EFGR has emerged as an additional mechanism for RON activation, which is critical for tumorigenic develop- ment. The RON signaling crosstalk acts either as a regulatory feedback loop that strengthens or enhances tumor- igenic phenotype of cancer cells or serves as a signaling compensatory pathway providing a growth/survival ad- vantage for cancer cells to escape targeted therapy. Moreover, viral oncoproteins derived from Friend leukemia or Epstein-Barr viruses interact with RON to drive viral oncogenesis. In cancer cells, RON signaling is integrated into cellular signaling network essential for cancer cell growth and survival. These activities provide the mo- lecular basis of targeting RON for cancer treatment. In this review, we will discuss recent data that uncover the mechanisms of RON activation in cancer cells, review evidence of RON signaling crosstalk relevant to cancer malignancy, and emphasize the significance of the RON signaling addiction by cancer cells for tumor therapy. Understanding aberrant RON signaling will not only provide insight into the mechanisms of tumor pathogenesis, but also lead to the development of novel strategies for molecularly targeted cancer treatment.展开更多
Immune system is a complex network that clears pathogens,toxic substrates,and cancer cells.Distinguishing self-antigens from non-self-antigens is critical for the immune cell-mediated response against foreign antigens...Immune system is a complex network that clears pathogens,toxic substrates,and cancer cells.Distinguishing self-antigens from non-self-antigens is critical for the immune cell-mediated response against foreign antigens.The innate immune system elicits an early-phase response to various stimuli,whereas the adaptive immune response is tailored to previously encountered antigens.During immune responses,B cells differentiate into antibody-secreting cells,while naïve T cells differentiate into functionally specific effector cells[T helper 1(Th1),Th2,Th17,and regulatory T cells].However,enhanced or prolonged immune responses can result in autoimmune disorders,which are characterized by lymphocytemediated immune responses against self-antigens.Signal transduction of cytokines,which regulate the inflammatory cascades,is dependent on the members of the Janus family of protein kinases.Tyrosine kinase 2(Tyk2)is associated with receptor subunits of immune-related cytokines,such as type I interferon,interleukin(IL)-6,IL-10,IL-12,and IL-23.Clinical studies on the therapeutic effects and the underlying mechanisms of Tyk2 inhibitors in autoimmune or chronic inflammatory diseases are currently ongoing.This review summarizes the findings of studies examining the role of Tyk2 in immune and/or inflammatory responses using Tyk2-deficient cells and mice.展开更多
Objective:This study aimed to investigate the role of receptor tyrosine kinase-like orphan receptor 2(ROR2)in triple-negative breast cancer(TNBC).Methods:ROR2 expression in primary TNBC and metastatic TNBC tissues was...Objective:This study aimed to investigate the role of receptor tyrosine kinase-like orphan receptor 2(ROR2)in triple-negative breast cancer(TNBC).Methods:ROR2 expression in primary TNBC and metastatic TNBC tissues was analyzed by immunohistochemical staining and PCR.ROR2 expression in TNBC cell lines was detected by PCR and Western blot analysis.The migration,invasion and chemosensitivity of TNBC cells with overexpression or knockdown of ROR2 were examined.Results:ROR2 expression was high in metastatic TNBC tissues.ROR2 knockdown suppressed the migration,invasion and chemoresistance of TNBC cells.ROR2 overexpression in MDA-MB-435 cells promoted the migration,invasion,and chemoresistance.Moreover,ROR2 knockdown in HC1599 and MDA-MB-435 adriamycin-resistant cells enhanced chemosensitivity to adriamycin.ROR2 could activate PI3K/AKT/mTOR signaling in TNBC cells.Conclusion:ROR2 is upregulated and promotes metastatic phenotypes of TNBC by activating PI3K/AKT/mTOR signaling.展开更多
AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles pe...AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles per liter of caerulein(Cae)was administrated to induce the apoptosis of AR42 J cells and the apoptosis rate was detected by flow cytometry analysis. An amylase assay kit was used to measure the amylase expression level in the supernatant. Quantitative real-time PCR(qRT-PCR)was adopted to measure miR-22 expression. We used online tools to predict the potential transcription promoter of miR-22 and the binding sites, which was further identified by using luciferase reporter analysis,chromatin immunoprecipitation(ChIP) and ChIPqP CR assays. Then, a mimic of miR-22, Nr3 c1 plasmid encoding the glucocorticoid receptor(GR), and siNr3 c1 were used to transfect AR42 J cells, respectively.The mRNA expression of miR-22, Nr3 c1, and Erb-b2 receptor tyrosine kinase 3(ErbB3) was confirmed by qRT-PCR and the apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of ErbB3, GR, PI3 k, PI3 kp85α, Akt, p-Akt, Bad, Bax, Bcl-xl, Bcl-2, and cleaved caspase3.RESULTS After inducing apoptosis of AR42 J cells in vitro, the expression of miR-22 was significantly increased by2.20 ± 0.26 and 4.19 ± 0.54 times, respectively, at3 h and 6 h in comparison with the control group.As revealed by qRT-PCR assay, the expression of miR-22 was 78.25 ± 6.61 times higher in the miR-22 mimic group relative to the miRNA control group,accompanied with an obviously increased acinar cell apoptosis rate(32.53 ± 1.15 vs 18.07 ± 0.89, P =0.0006). The upregulation of miR-22 could suppress its target gene, ErbB3, and the phosphorylation of PI3 k and Akt. Furthermore, we predicted the potential transcription promoter of miR-22 and the binding sites using online tools. Luciferase reporter analysis and sitedirected mutagenesis indicated that the binding site(GACAGCCATGTACA) of the GR, which is encoded by the Nr3 c1 gene. Downregulation of the expression of GR could upregulate the expression of miR-22, which further promoted the apoptosis of AR42 J cells.CONCLUSION GR transcriptionally represses the expression of miR-22,which further promotes the apoptosis of pancreatic acinar cells by downregulating the downstream signaling pathway.展开更多
AIMTo evaluate whether protein tyrosine phosphatase 1B (PTP1B) contributed to initiate human retinal pigment epithelium cells (A)-19 migration and investigate the signaling pathways involved in this process.METHODSARP...AIMTo evaluate whether protein tyrosine phosphatase 1B (PTP1B) contributed to initiate human retinal pigment epithelium cells (A)-19 migration and investigate the signaling pathways involved in this process.METHODSARPE-19 cells were cultured and treated with the siRNA-PTP1B. Expression of PTP1B was confirmed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). AG1478 [a selective inhibitor of epidermal growth factor receptor (EGFR)] and PD98059 (a specific inhibitor of the activation of mitogen-activated protein kinase) were used to help to determine the PTP1B signaling mechanism. Western blot analysis verified expression of EGFR and extracellular signal-regulated kinase (ERK) in ARPE-19 cells. The effect of siRNA-PTP1B on cell differentiation was confirmed by immunostaining for α-smooth muscle actin (α-SMA) and qRT-PCR. Cell migration ability was analyzed by transwell chamber assay.RESULTSThe mRNA levels of PTP1B were reduced by siRNA-PTP1B as determined by qRT-PCR assay. SiRNA-PTP1B activated EGFR and ERK phosphorylation. α-SMA staining and qRT-PCR assay demonstrated that siRNA-PTP1B induced retinal pigment epithelium (RPE) cells to differentiate toward better contractility and motility. Transwell chamber assay proved that PTP1B inhibition improved migration activity of RPE cells. Treatment with AG1478 and PD98059 abolished siRNA-PTP1B-induced activation of EGFR and ERK, α-SMA expression and cell migration.CONCLUSIONPTP1B inhibition promoted myofibroblast differentiation and migration of ARPE-19 cells, and EGFR/ERK signaling pathway played important role in migration process.展开更多
AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cel...AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC 50 ) and reversal index (IC 50 in experimental group/IC 50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 μg/mL and 10 μmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 μmol/L in HepG2/OXA cells, the IC 50 decreased to 39.65 μmol/L after treatment with 10 μmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/ OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway.展开更多
目的:探讨鸢尾素调节Janus蛋白酪氨酸激酶2(Janus protein tyrosine kinase 2,JAK2)/信号转导和转录激活子3(Signal transduction and activator of transcription 3,STAT3)信号通路对牙周炎大鼠牙周组织损伤的影响。方法:通过结扎和接...目的:探讨鸢尾素调节Janus蛋白酪氨酸激酶2(Janus protein tyrosine kinase 2,JAK2)/信号转导和转录激活子3(Signal transduction and activator of transcription 3,STAT3)信号通路对牙周炎大鼠牙周组织损伤的影响。方法:通过结扎和接种牙龈卟啉单胞菌液建立牙周炎大鼠模型,将大鼠随机分为模型组、鸢尾素低(鸢尾素-L,50 mg/kg)、中(鸢尾素-M,100 mg/kg)、高剂量(鸢尾素-H,200 mg/kg)组、鸢尾素-H+激活剂(200 mg/kg鸢尾素+2 mg/kg香豆霉素)组,每组10只,并以注射等体积生理盐水的正常大鼠对照组。干预结束后,对大鼠牙龈出血指数、牙齿松动度评分;牙槽骨吸收、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)、白细胞介素(Interleukin,IL)-6、IL-1β以及丙二醛(Malondialdehyde,MDA)、超氧化物歧化酶(Superoxide dismutase,SOD)水平分别以Micro-CT试剂盒检测;HE检测牙周组织病理学变化;Western blot检测JAK2、STAT3、p-JAK2、p-STAT3蛋白表达。结果:与对照组相比,模型组大鼠牙周组织被破坏,炎性浸润严重,牙龈出血指数、牙齿松动度评分、牙槽骨吸收、TNF-α、IL-6、IL-1β、MDA水平、p-JAK2/JAK2、p-STAT3/STAT3表达显著增加,SOD水平显著降低(P<0.05);与模型组相比,不同剂量的鸢尾素组大鼠病理损伤得到改善,牙龈出血指数、牙齿松动度评分、牙槽骨吸收、TNF-α、IL-6、IL-1β、MDA水平、p-JAK2/JAK2、p-STAT3/STAT3表达显著降低,SOD水平显著增加,具有剂量依赖性(P<0.05);与鸢尾素-H组相比,鸢尾素-H组+激活剂组大鼠病理损伤加重,大鼠牙龈出血指数、牙齿松动度评分、牙槽骨吸收、TNF-α、IL-6、IL-1β、MDA水平、p-JAK2/JAK2、p-STAT3/STAT3表达显著增加,SOD水平显著降低(P<0.05)。结论:鸢尾素抑制牙周炎大鼠氧化应激、炎性反应,减轻大鼠牙周组织损伤,减少牙槽骨吸收,可能与抑制JAK2/STAT3信号通路有关。展开更多
Cigarette smoking is correlated with the development of various cancers. 4- （Methylnitresoamino） -1- （3-pyridyl） - 1-butanone（NNK） is one of the major tobacco-specific carcinogens in the cigarette smoke, which i...Cigarette smoking is correlated with the development of various cancers. 4- （Methylnitresoamino） -1- （3-pyridyl） - 1-butanone（NNK） is one of the major tobacco-specific carcinogens in the cigarette smoke, which increases the risk of breast cancer. In the present study, it was demonstrated that NNK rapidly activated ERK1 and ERK2 MAP kinases in human normal mammary epithelial cells. It was found that there are two different routes for the activation of ERK1/2 with NNK. One is from nicotinic receptor nAchR to MEK1/2, and the other is from tyrosine kinase containing receptor to MEK1/2. The tobacco-specific carcinogen NNK shows a strong proliferative effect on normal human mammary epithelial cells and cancer mammary epithelial cells.展开更多
OBJECTIVE:To observe the effect of electroacupuncture(EA)stimulating Zusanli(ST36),Sanyinjiao(SP6)on inhibition of osteoclastogenesis and the role of the adenosine A2A receptor(A2AR)and the p38αMitogen-Activated Prot...OBJECTIVE:To observe the effect of electroacupuncture(EA)stimulating Zusanli(ST36),Sanyinjiao(SP6)on inhibition of osteoclastogenesis and the role of the adenosine A2A receptor(A2AR)and the p38αMitogen-Activated Protein Kinase(MAPK)signaling pathway in mediating this effect.METHODS:Mice with collagen induced arthritis(CIA)received different treatments.Immunohistochemistry and western blotting were used to determine the levels of multiple signaling molecules in these joints[receptor activator of nuclear transcription factor-κB(NF-κB)ligand(RANKL),receptor activator of NF-κB(RANK),tumor necrosis factor receptor associated factor 6(TRAF6),p38α,NF-κB,and nuclear factor of activated T cells C1(NFATc1)].Osteoclasts were identified using tartrate-resistant acid phosphatase(TRAP)staining.RESULTS:The immunohistochemistry results indicated upregulation of p38α,NF-κB,and NFATc1 in the CIA-control and CIA-EA-SCH58261 groups,but reduced levels in the CIA-EA group.Western blotting indicated upregulation of RANKL,RANK,TRAF6,p38α,NF-κB,and NFATc1 in the CIA-control and CIA-EA-SCH58261 groups,but reduced expression in the CIA-EA group.Osteoclasts were more abundant in the CIA-control and CIA-EA-SCH58261 groups than in the CIA-EA group.CONCLUSIONS:EA treatment enhanced the A2AR activity and inhibited osteoclast formation by inhibition of RANKL,RANK,TRAF6,p38α,NF-κB,and NFATc1.SCH58261 reversed the effect of EA.These results suggest that EA regulated p38α-MAPK signaling by increasing A2AR activity,which inhibited osteoclastogenesis.展开更多
基金supported in part by National Institutes of Health grantR01 CA91980 (MHW)a grant from the Amarillo Area Foundation(MHW)supported by NIH grants R01 CA112029 and CA121211
文摘The RON receptor tyrosine kinase, a member of the MET proto-oncogene family, is a pathogenic factor im- plicated in tumor malignancy. Specifically, aberrations in RON signaling result in increased cancer cell growth, survival, invasion, angiogenesis, and drug resistance. Biochemical events such as ligand binding, receptor over- expression, generation of structure-defected variants, and point mutations in the kinase domain contribute to RON signaling activation. Recently, functional crosstalk between RON and signaling proteins such as MET and EFGR has emerged as an additional mechanism for RON activation, which is critical for tumorigenic develop- ment. The RON signaling crosstalk acts either as a regulatory feedback loop that strengthens or enhances tumor- igenic phenotype of cancer cells or serves as a signaling compensatory pathway providing a growth/survival ad- vantage for cancer cells to escape targeted therapy. Moreover, viral oncoproteins derived from Friend leukemia or Epstein-Barr viruses interact with RON to drive viral oncogenesis. In cancer cells, RON signaling is integrated into cellular signaling network essential for cancer cell growth and survival. These activities provide the mo- lecular basis of targeting RON for cancer treatment. In this review, we will discuss recent data that uncover the mechanisms of RON activation in cancer cells, review evidence of RON signaling crosstalk relevant to cancer malignancy, and emphasize the significance of the RON signaling addiction by cancer cells for tumor therapy. Understanding aberrant RON signaling will not only provide insight into the mechanisms of tumor pathogenesis, but also lead to the development of novel strategies for molecularly targeted cancer treatment.
基金Supported by Grant-in-Aid for scientific research from Ministry of Education,Culture,Sports,Science and Technology of Japan,No.19H03364 and No.20K07010。
文摘Immune system is a complex network that clears pathogens,toxic substrates,and cancer cells.Distinguishing self-antigens from non-self-antigens is critical for the immune cell-mediated response against foreign antigens.The innate immune system elicits an early-phase response to various stimuli,whereas the adaptive immune response is tailored to previously encountered antigens.During immune responses,B cells differentiate into antibody-secreting cells,while naïve T cells differentiate into functionally specific effector cells[T helper 1(Th1),Th2,Th17,and regulatory T cells].However,enhanced or prolonged immune responses can result in autoimmune disorders,which are characterized by lymphocytemediated immune responses against self-antigens.Signal transduction of cytokines,which regulate the inflammatory cascades,is dependent on the members of the Janus family of protein kinases.Tyrosine kinase 2(Tyk2)is associated with receptor subunits of immune-related cytokines,such as type I interferon,interleukin(IL)-6,IL-10,IL-12,and IL-23.Clinical studies on the therapeutic effects and the underlying mechanisms of Tyk2 inhibitors in autoimmune or chronic inflammatory diseases are currently ongoing.This review summarizes the findings of studies examining the role of Tyk2 in immune and/or inflammatory responses using Tyk2-deficient cells and mice.
基金supported by Medical and Health Research Project of Nanjing Health Science and Technology Development Special Fund(ZKX21040).
文摘Objective:This study aimed to investigate the role of receptor tyrosine kinase-like orphan receptor 2(ROR2)in triple-negative breast cancer(TNBC).Methods:ROR2 expression in primary TNBC and metastatic TNBC tissues was analyzed by immunohistochemical staining and PCR.ROR2 expression in TNBC cell lines was detected by PCR and Western blot analysis.The migration,invasion and chemosensitivity of TNBC cells with overexpression or knockdown of ROR2 were examined.Results:ROR2 expression was high in metastatic TNBC tissues.ROR2 knockdown suppressed the migration,invasion and chemoresistance of TNBC cells.ROR2 overexpression in MDA-MB-435 cells promoted the migration,invasion,and chemoresistance.Moreover,ROR2 knockdown in HC1599 and MDA-MB-435 adriamycin-resistant cells enhanced chemosensitivity to adriamycin.ROR2 could activate PI3K/AKT/mTOR signaling in TNBC cells.Conclusion:ROR2 is upregulated and promotes metastatic phenotypes of TNBC by activating PI3K/AKT/mTOR signaling.
基金National Natural Science Foundation of China,No.31671440
文摘AIM To elucidate the underlying mechanism that microRNA-22(miR-22) promotes the apoptosis of rat pancreatic acinar cells(AR42 J) and the elements that regulate the expression of miR-22.METHODS One hundred nanomoles per liter of caerulein(Cae)was administrated to induce the apoptosis of AR42 J cells and the apoptosis rate was detected by flow cytometry analysis. An amylase assay kit was used to measure the amylase expression level in the supernatant. Quantitative real-time PCR(qRT-PCR)was adopted to measure miR-22 expression. We used online tools to predict the potential transcription promoter of miR-22 and the binding sites, which was further identified by using luciferase reporter analysis,chromatin immunoprecipitation(ChIP) and ChIPqP CR assays. Then, a mimic of miR-22, Nr3 c1 plasmid encoding the glucocorticoid receptor(GR), and siNr3 c1 were used to transfect AR42 J cells, respectively.The mRNA expression of miR-22, Nr3 c1, and Erb-b2 receptor tyrosine kinase 3(ErbB3) was confirmed by qRT-PCR and the apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of ErbB3, GR, PI3 k, PI3 kp85α, Akt, p-Akt, Bad, Bax, Bcl-xl, Bcl-2, and cleaved caspase3.RESULTS After inducing apoptosis of AR42 J cells in vitro, the expression of miR-22 was significantly increased by2.20 ± 0.26 and 4.19 ± 0.54 times, respectively, at3 h and 6 h in comparison with the control group.As revealed by qRT-PCR assay, the expression of miR-22 was 78.25 ± 6.61 times higher in the miR-22 mimic group relative to the miRNA control group,accompanied with an obviously increased acinar cell apoptosis rate(32.53 ± 1.15 vs 18.07 ± 0.89, P =0.0006). The upregulation of miR-22 could suppress its target gene, ErbB3, and the phosphorylation of PI3 k and Akt. Furthermore, we predicted the potential transcription promoter of miR-22 and the binding sites using online tools. Luciferase reporter analysis and sitedirected mutagenesis indicated that the binding site(GACAGCCATGTACA) of the GR, which is encoded by the Nr3 c1 gene. Downregulation of the expression of GR could upregulate the expression of miR-22, which further promoted the apoptosis of AR42 J cells.CONCLUSION GR transcriptionally represses the expression of miR-22,which further promotes the apoptosis of pancreatic acinar cells by downregulating the downstream signaling pathway.
基金Supported by Shandong Provincial Natural Science Foundation,China(No.ZR2012HQ004)the Research Fund for Fundamental Research Project of Qingdao(No.13-1-4-180-jch)+1 种基金the Scientific Research Fund of Huangdao District of Qingdao City(No.2014-1-74)the Young People Scientific Research Fund of Affiliated Hospital,Qingdao University(No.QDFY134)
文摘AIMTo evaluate whether protein tyrosine phosphatase 1B (PTP1B) contributed to initiate human retinal pigment epithelium cells (A)-19 migration and investigate the signaling pathways involved in this process.METHODSARPE-19 cells were cultured and treated with the siRNA-PTP1B. Expression of PTP1B was confirmed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). AG1478 [a selective inhibitor of epidermal growth factor receptor (EGFR)] and PD98059 (a specific inhibitor of the activation of mitogen-activated protein kinase) were used to help to determine the PTP1B signaling mechanism. Western blot analysis verified expression of EGFR and extracellular signal-regulated kinase (ERK) in ARPE-19 cells. The effect of siRNA-PTP1B on cell differentiation was confirmed by immunostaining for α-smooth muscle actin (α-SMA) and qRT-PCR. Cell migration ability was analyzed by transwell chamber assay.RESULTSThe mRNA levels of PTP1B were reduced by siRNA-PTP1B as determined by qRT-PCR assay. SiRNA-PTP1B activated EGFR and ERK phosphorylation. α-SMA staining and qRT-PCR assay demonstrated that siRNA-PTP1B induced retinal pigment epithelium (RPE) cells to differentiate toward better contractility and motility. Transwell chamber assay proved that PTP1B inhibition improved migration activity of RPE cells. Treatment with AG1478 and PD98059 abolished siRNA-PTP1B-induced activation of EGFR and ERK, α-SMA expression and cell migration.CONCLUSIONPTP1B inhibition promoted myofibroblast differentiation and migration of ARPE-19 cells, and EGFR/ERK signaling pathway played important role in migration process.
基金Supported by National Natural Sciences Foundation of China,No. 81001067the Ministry of Science and Technology International Cooperation Project, No. 2010DFA31870the AstraZeneca Special Research Foundation for Targeted Therapy of the Wu Jieping Medical Foundation, No. 320.6700.09068
文摘AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC 50 ) and reversal index (IC 50 in experimental group/IC 50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 μg/mL and 10 μmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 μmol/L in HepG2/OXA cells, the IC 50 decreased to 39.65 μmol/L after treatment with 10 μmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/ OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway.
基金Supported by the Natural Science Foundation of Jilin Province(No 200305-50-1)
文摘Cigarette smoking is correlated with the development of various cancers. 4- （Methylnitresoamino） -1- （3-pyridyl） - 1-butanone（NNK） is one of the major tobacco-specific carcinogens in the cigarette smoke, which increases the risk of breast cancer. In the present study, it was demonstrated that NNK rapidly activated ERK1 and ERK2 MAP kinases in human normal mammary epithelial cells. It was found that there are two different routes for the activation of ERK1/2 with NNK. One is from nicotinic receptor nAchR to MEK1/2, and the other is from tyrosine kinase containing receptor to MEK1/2. The tobacco-specific carcinogen NNK shows a strong proliferative effect on normal human mammary epithelial cells and cancer mammary epithelial cells.
基金National Natural Science Foundation of China:the Mechanism of Adenosine A2A Receptor Modulate Electroacupuncture Inhibiting Osteoclast Formation in Mice with Collagen-Induced Arthritis (No.81674053)Zhejiang Basic Public Welfare Research Project:the Role of P38 MAPK Pathway in the Inhibition of CIA Osteoclast Differentiation by Electroacupuncture via Adenosine Pathway (No.LY20H270015)+1 种基金Basic Medical and Health Technology Project of Wenzhou Science and Technology Bureau:Electroacupuncture of Mice with CIA Mitigate Joint Damage by the p38MAPK Pathway (No.Y20190198)Scientific Research Incubation Project of the First Affiliated Hospital of Wenzhou Medical University:Electroacupuncture of Mice with CIA Mitigate Joint Damage by the p38MAPK Pathway (No.FHY2019021)
文摘OBJECTIVE:To observe the effect of electroacupuncture(EA)stimulating Zusanli(ST36),Sanyinjiao(SP6)on inhibition of osteoclastogenesis and the role of the adenosine A2A receptor(A2AR)and the p38αMitogen-Activated Protein Kinase(MAPK)signaling pathway in mediating this effect.METHODS:Mice with collagen induced arthritis(CIA)received different treatments.Immunohistochemistry and western blotting were used to determine the levels of multiple signaling molecules in these joints[receptor activator of nuclear transcription factor-κB(NF-κB)ligand(RANKL),receptor activator of NF-κB(RANK),tumor necrosis factor receptor associated factor 6(TRAF6),p38α,NF-κB,and nuclear factor of activated T cells C1(NFATc1)].Osteoclasts were identified using tartrate-resistant acid phosphatase(TRAP)staining.RESULTS:The immunohistochemistry results indicated upregulation of p38α,NF-κB,and NFATc1 in the CIA-control and CIA-EA-SCH58261 groups,but reduced levels in the CIA-EA group.Western blotting indicated upregulation of RANKL,RANK,TRAF6,p38α,NF-κB,and NFATc1 in the CIA-control and CIA-EA-SCH58261 groups,but reduced expression in the CIA-EA group.Osteoclasts were more abundant in the CIA-control and CIA-EA-SCH58261 groups than in the CIA-EA group.CONCLUSIONS:EA treatment enhanced the A2AR activity and inhibited osteoclast formation by inhibition of RANKL,RANK,TRAF6,p38α,NF-κB,and NFATc1.SCH58261 reversed the effect of EA.These results suggest that EA regulated p38α-MAPK signaling by increasing A2AR activity,which inhibited osteoclastogenesis.
