Mitogen-activated protein kinases(MAPKs) are the main regulators of cellular proliferation, growth, and survival in physiological or pathological conditions. Aberrant MAPK signaling plays a pivotal role in carcinogene...Mitogen-activated protein kinases(MAPKs) are the main regulators of cellular proliferation, growth, and survival in physiological or pathological conditions. Aberrant MAPK signaling plays a pivotal role in carcinogenesis, which leads to development and progression of human cancer. Dual-specificity phosphatase 6(DUSP6), a member of the MAPK phosphatase family, interacts with specifically targeted extracellular signal-regulated kinase 1/2 via negative feedback regulation in the MAPK pathway of mammalian cells. This phosphatase functions in a dual manner, pro-oncogenic or tumor-suppressive, depending on the type of cancer. To date, the tumor-suppressive role of DUSP6 has been demonstrated in pancreatic cancer, non-small cell lung cancer, esophageal squamous cell and nasopharyngeal carcinoma, and ovarian cancer. Its pro-oncogenic role has been observed in human glioblastoma, thyroid carcinoma, breast cancer, and acute myeloid carcinoma. Both roles of DUSP6 have been documented in malignant melanoma depending on the histological subtype of the cancer. Loss-or gain-of-function effects of DUSP6 in these cancers highlights the significance of this phosphatase in carcinogenesis. Development of methods that use the DUSP6 gene as a therapeutic target for cancer treatment or as a prognostic factor for diagnosis and evaluation of cancer treatment outcome has great potential. This review focuses on molecular characteristics of the DUSP6 gene and its role in cancers in the purview of development, progression, and cancer treatment outcome.展开更多
Platelet-activating factor (PAF) is a potent inflammatory phospholipid mediator that is known to play a role in early-phase responses in asthma and other diseases. Through its high affinity receptor, PAFR, PAF is know...Platelet-activating factor (PAF) is a potent inflammatory phospholipid mediator that is known to play a role in early-phase responses in asthma and other diseases. Through its high affinity receptor, PAFR, PAF is known to activate multiple signalling pathways contributing to its proinflammatory effects. Of these pathways, the mitogen-activated protein kinase (MAPK) cascade is initiated upon PAF stimulation, leading to the activation of the conventional MAPKs ERK1/2, p38 and JNK. Since dual-specificity phosphatases (DUSP) downregulated MAPK activity, we postulated that PAF could also enhance DUSP expression and thus induced an autoregulatory loop. In this report, we studied the effect of PAF on DUSP mRNA expression in human monocytes. Our results demonstrate that PAF induces DUSP1 and DUSP5 gene expression in a time- and concentration-dependent manner, with maximal effects at PAF 100 nM and at 20 - 30 min of stimulation. In contrast, DUSP2 and DUSP6 gene expression was not enhanced by PAF. Moreover, leukotriene D4, another lipid mediator of inflammation, was unable to modulate DUSP expression. PAF-induced DUSP expression was prevented by the PAFR antagonist WEB2170 and by pretreatment with the transcriptional inhibitor Actinomycin D. Moreover, enhanced DUSP5, but not DUSP1 expression was prevented by pretreatment with the ERK inhibitor PD98059 or the PI3K inhibitor Wortmannin. Taken together, our results indicate that PAF selectively enhances DUSP1 and DUSP5 gene expressions through PAFR activation, and suggest that PAF may have an active role in the resolution of inflammation by its ability to upregulate the two DUSPs and thus provide a negative auto-regulatory signalling mechanism.展开更多
Background： Previously, we reported that dual-specificity adenocarcinoma （EEA）. However, the role of DUSP1 medroxyprogesterone （MPA） are still unclear. phosphatase I （DUSPI） was differentially expressed in endo...Background： Previously, we reported that dual-specificity adenocarcinoma （EEA）. However, the role of DUSP1 medroxyprogesterone （MPA） are still unclear. phosphatase I （DUSPI） was differentially expressed in endometrioid in EEA progression and the relationship between DUSPI and Methods： The expression of DUSPI in EEA specimens was detected by immunohistochemical analysis. The effect of DUSPI on cell proliferation was analyzed by Cell Counting Kit 8 and colony formation assay, and cell migration was analyzed by transwell assay. MPA-induced DUSPI expression in EEA cells was measured by Western blot. Results： DUSPI expression was deficient in advanced International Federation of Gynecology and Obstetrics stage, high-grade and myometrial invasive EEA. In EEA cell lines （HeclA, Hecl B, RL952, and Ishikawa）, the DUSP1 expression was substantially higher in lshikawa cells than in other cell lines （P 〈 0.05）. Knockdown ofDUSP I promoted lshikawa cells proliferation, migration, and activation of mitogen-activated protein kinases/extracellular signal-regulated kinase （MAPK/Erk） pathway. MPA-induced DUSP1 expression and inhibited MAPK/Erk pathway in Ishikawa cells. Conclusions： Our data suggest that DUSP1 deficiency promotes EEA progression via MAPK/Erk pathway, which may be reversed by MPA, suggesting that DUSP I may serve as a potential therapeutic target for the treatment of EEA.展开更多
Ferroptosis is a oxidative damage-dependent form of regulated cell death that has become an emerging target for disease prevention and treatment.Here,we show that dual-specificity phosphatase 1(DUSP1),a phosphatase pl...Ferroptosis is a oxidative damage-dependent form of regulated cell death that has become an emerging target for disease prevention and treatment.Here,we show that dual-specificity phosphatase 1(DUSP1),a phosphatase playing multiple roles in stress-signaling pathways,is a new repressor of ferroptosis in human pancreatic cancer cells.Several classical ferroptosis activators(eg,erastin and RSL3)induce the expression of DUSP1,but not other members of DUSP,which depends on extracellular signal-regulated protein kinases 1 and 2(ERK1/2).Moreover,shRNA-mediated DUSP1 knockdown increases the anticancer activity of ferroptosis activators in pancreatic cancer cells through activating lipid peroxidation in vitro and in vivo.Importantly,DUSP1-mediated autophagy is responsible for lipid peroxidation-mediated ferroptotic cell death.Thus,the DUSP1-related ferroptotic pathway may represent a potential target for therapeutic intervention in pancreatic cancer.展开更多
基金funded by a grant from Fundamental Research Grant Scheme, Ministry of Higher Education Malaysia (Grant No. 203.CIPPT.6711505)
文摘Mitogen-activated protein kinases(MAPKs) are the main regulators of cellular proliferation, growth, and survival in physiological or pathological conditions. Aberrant MAPK signaling plays a pivotal role in carcinogenesis, which leads to development and progression of human cancer. Dual-specificity phosphatase 6(DUSP6), a member of the MAPK phosphatase family, interacts with specifically targeted extracellular signal-regulated kinase 1/2 via negative feedback regulation in the MAPK pathway of mammalian cells. This phosphatase functions in a dual manner, pro-oncogenic or tumor-suppressive, depending on the type of cancer. To date, the tumor-suppressive role of DUSP6 has been demonstrated in pancreatic cancer, non-small cell lung cancer, esophageal squamous cell and nasopharyngeal carcinoma, and ovarian cancer. Its pro-oncogenic role has been observed in human glioblastoma, thyroid carcinoma, breast cancer, and acute myeloid carcinoma. Both roles of DUSP6 have been documented in malignant melanoma depending on the histological subtype of the cancer. Loss-or gain-of-function effects of DUSP6 in these cancers highlights the significance of this phosphatase in carcinogenesis. Development of methods that use the DUSP6 gene as a therapeutic target for cancer treatment or as a prognostic factor for diagnosis and evaluation of cancer treatment outcome has great potential. This review focuses on molecular characteristics of the DUSP6 gene and its role in cancers in the purview of development, progression, and cancer treatment outcome.
文摘Platelet-activating factor (PAF) is a potent inflammatory phospholipid mediator that is known to play a role in early-phase responses in asthma and other diseases. Through its high affinity receptor, PAFR, PAF is known to activate multiple signalling pathways contributing to its proinflammatory effects. Of these pathways, the mitogen-activated protein kinase (MAPK) cascade is initiated upon PAF stimulation, leading to the activation of the conventional MAPKs ERK1/2, p38 and JNK. Since dual-specificity phosphatases (DUSP) downregulated MAPK activity, we postulated that PAF could also enhance DUSP expression and thus induced an autoregulatory loop. In this report, we studied the effect of PAF on DUSP mRNA expression in human monocytes. Our results demonstrate that PAF induces DUSP1 and DUSP5 gene expression in a time- and concentration-dependent manner, with maximal effects at PAF 100 nM and at 20 - 30 min of stimulation. In contrast, DUSP2 and DUSP6 gene expression was not enhanced by PAF. Moreover, leukotriene D4, another lipid mediator of inflammation, was unable to modulate DUSP expression. PAF-induced DUSP expression was prevented by the PAFR antagonist WEB2170 and by pretreatment with the transcriptional inhibitor Actinomycin D. Moreover, enhanced DUSP5, but not DUSP1 expression was prevented by pretreatment with the ERK inhibitor PD98059 or the PI3K inhibitor Wortmannin. Taken together, our results indicate that PAF selectively enhances DUSP1 and DUSP5 gene expressions through PAFR activation, and suggest that PAF may have an active role in the resolution of inflammation by its ability to upregulate the two DUSPs and thus provide a negative auto-regulatory signalling mechanism.
文摘Background： Previously, we reported that dual-specificity adenocarcinoma （EEA）. However, the role of DUSP1 medroxyprogesterone （MPA） are still unclear. phosphatase I （DUSPI） was differentially expressed in endometrioid in EEA progression and the relationship between DUSPI and Methods： The expression of DUSPI in EEA specimens was detected by immunohistochemical analysis. The effect of DUSPI on cell proliferation was analyzed by Cell Counting Kit 8 and colony formation assay, and cell migration was analyzed by transwell assay. MPA-induced DUSPI expression in EEA cells was measured by Western blot. Results： DUSPI expression was deficient in advanced International Federation of Gynecology and Obstetrics stage, high-grade and myometrial invasive EEA. In EEA cell lines （HeclA, Hecl B, RL952, and Ishikawa）, the DUSP1 expression was substantially higher in lshikawa cells than in other cell lines （P 〈 0.05）. Knockdown ofDUSP I promoted lshikawa cells proliferation, migration, and activation of mitogen-activated protein kinases/extracellular signal-regulated kinase （MAPK/Erk） pathway. MPA-induced DUSP1 expression and inhibited MAPK/Erk pathway in Ishikawa cells. Conclusions： Our data suggest that DUSP1 deficiency promotes EEA progression via MAPK/Erk pathway, which may be reversed by MPA, suggesting that DUSP I may serve as a potential therapeutic target for the treatment of EEA.
基金supported the National Natural Science Foundation of China(81802476 and 81772508).
文摘Ferroptosis is a oxidative damage-dependent form of regulated cell death that has become an emerging target for disease prevention and treatment.Here,we show that dual-specificity phosphatase 1(DUSP1),a phosphatase playing multiple roles in stress-signaling pathways,is a new repressor of ferroptosis in human pancreatic cancer cells.Several classical ferroptosis activators(eg,erastin and RSL3)induce the expression of DUSP1,but not other members of DUSP,which depends on extracellular signal-regulated protein kinases 1 and 2(ERK1/2).Moreover,shRNA-mediated DUSP1 knockdown increases the anticancer activity of ferroptosis activators in pancreatic cancer cells through activating lipid peroxidation in vitro and in vivo.Importantly,DUSP1-mediated autophagy is responsible for lipid peroxidation-mediated ferroptotic cell death.Thus,the DUSP1-related ferroptotic pathway may represent a potential target for therapeutic intervention in pancreatic cancer.
