Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulat...Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulatory mechanism for various physiological processes including cytoskeleton function,regulation of cell growth and death,modulation of ion channels and multiple signaling events.However,mechanisms underlying the functional diversity of Pyk2 are not clear.A Pyk2 isoform that encodes only part of the C-terminal domain of Pyk2,named as PRNK (Pyk2-related non-kinase),acts as a dominant-negative inhibitor of Pyk2-dependent signaling by displacing Pyk2 from focal adhesions.Research on functional PRNK probably provides new potential inhibitory tool targeting Pyk2 and makes it possible to explore more of Pyk2 pathological mechanism.PRNK is a promising candidate targeting Pyk2 modulation.This review focuses on the functional investigation of Pyk2 and its structure and localization,including recent research with inhibitory strategies targeting Pyk2 by the method of PRNK.展开更多
The body of evidence investigating human epidermal growth factor receptor-2(HER2)directed therapy in patients with breast cancer(BC)has been growing within the last decade.Recently,the use of tyrosine kinase inhibitor...The body of evidence investigating human epidermal growth factor receptor-2(HER2)directed therapy in patients with breast cancer(BC)has been growing within the last decade.Recently,the use of tyrosine kinase inhibitors(TKIs)has been of particular interest in the treatment of human malignancies.This literature commentary is intended to highlight the most recent findings associated with the widely-studied TKI agents and their clinical significance in improving the outcomes of HER2 positive BC.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
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
BACKGROUND: Electromagnetic radiation can influence dopamine (DA) synthesis in brain tissues or ceils, but electromagnetic frequencies, intensities, and radiation time can produce different effects. In addition, th...BACKGROUND: Electromagnetic radiation can influence dopamine (DA) synthesis in brain tissues or ceils, but electromagnetic frequencies, intensities, and radiation time can produce different effects. In addition, the signal pathway by which electromagnetic radiation influences DA synthesis remains controversial. OBJECTIVE: To determine tyrosine hydroxylase (TH) expression in PC12 cells and DA levels in cell culture media after different periods of low-frequency pulsed electric field (LF-PEF) stimulation, and to determine how LF-PEF signaling stimulates TH synthesis using inhibitors. DESIGN, TIME AND SETTING: A parallel, controlled, cell experiment was performed at the Laboratory of Cell Biology, School of Life Science, East China Normal University, between January and October 2006. MATERIALS: PC12 cells were purchased from the Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, China. Nerve growth factor was purchased from PeproTech, USA. The protein kinase A inhibitor, H-89, and mitogen-activated protein kinase kinase inhibitor, U0126, were purchased from Sigma, USA. METHODS: (1) Following routine culture in Dulbecco's modified eagle medium, primary PC12 cells were stimulated under LF-PEF (pulse frequency 50.Hz, pulse width 20 μs, peak field strength 1 V/m) for 5, 10, 15, 20, and 30 minutes. (2) Inhibitors (H-89 or U0126, 1 μmol/L) were added 30 minutes before LF-PEF stimulation for 10 minutes. MAIN OUTCOME MEASURES: (1) TH expression was determined by Western blot in PC12 cells at 0.5, 1,2, 3, and 4 days after LF-PEF stimulation. Similarly, DA was measured by high-performance liquid chromatography in media at 2, 3, 4, or 5 days after LF-PEE (2) TH expression was detected 1 day after H-89 or U0126 treatment and LF-PEE RESULTS: (1) Short-term LF-PEF stimulation (5 and 10 minutes) increased TH expression and media DA levels after short-term culture (2 days) (P 〈 0.01), but both parameters decreased with longer culture (3 4 days) (P 〈 0.01). Long-term LF-PEF stimulation (15, 20, or 30 minutes) decreased TH and DA synthesis, followed by a rapid increase (P 〈 0.01). (2) H89 could completely inhibit TH expression in PC12 cells stimulated by LF-PEF for 10 minutes, while the inhibition rate of U0126 was 53.2%. CONCLUSION: Short-term LF-PEF first promotes then inhibits, while long-term LF-PEF first inhibits then promotes, TH and DA synthesis. LF-PEF stimulation regulates TH expression primarily by activating protein kinase A to regulate DA synthesis.展开更多
基金Supported by the National Natural Science Foundation of China(30700822)
文摘Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulatory mechanism for various physiological processes including cytoskeleton function,regulation of cell growth and death,modulation of ion channels and multiple signaling events.However,mechanisms underlying the functional diversity of Pyk2 are not clear.A Pyk2 isoform that encodes only part of the C-terminal domain of Pyk2,named as PRNK (Pyk2-related non-kinase),acts as a dominant-negative inhibitor of Pyk2-dependent signaling by displacing Pyk2 from focal adhesions.Research on functional PRNK probably provides new potential inhibitory tool targeting Pyk2 and makes it possible to explore more of Pyk2 pathological mechanism.PRNK is a promising candidate targeting Pyk2 modulation.This review focuses on the functional investigation of Pyk2 and its structure and localization,including recent research with inhibitory strategies targeting Pyk2 by the method of PRNK.
基金Supported by the Elsa U.Pardee Foundation Grant,No.671432(to Sahu RP)NIH R21 Grant,No.ES033806(to Sahu RP).
文摘The body of evidence investigating human epidermal growth factor receptor-2(HER2)directed therapy in patients with breast cancer(BC)has been growing within the last decade.Recently,the use of tyrosine kinase inhibitors(TKIs)has been of particular interest in the treatment of human malignancies.This literature commentary is intended to highlight the most recent findings associated with the widely-studied TKI agents and their clinical significance in improving the outcomes of HER2 positive BC.
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the National Natural Science Foundation of China,No.50677022
文摘BACKGROUND: Electromagnetic radiation can influence dopamine (DA) synthesis in brain tissues or ceils, but electromagnetic frequencies, intensities, and radiation time can produce different effects. In addition, the signal pathway by which electromagnetic radiation influences DA synthesis remains controversial. OBJECTIVE: To determine tyrosine hydroxylase (TH) expression in PC12 cells and DA levels in cell culture media after different periods of low-frequency pulsed electric field (LF-PEF) stimulation, and to determine how LF-PEF signaling stimulates TH synthesis using inhibitors. DESIGN, TIME AND SETTING: A parallel, controlled, cell experiment was performed at the Laboratory of Cell Biology, School of Life Science, East China Normal University, between January and October 2006. MATERIALS: PC12 cells were purchased from the Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, China. Nerve growth factor was purchased from PeproTech, USA. The protein kinase A inhibitor, H-89, and mitogen-activated protein kinase kinase inhibitor, U0126, were purchased from Sigma, USA. METHODS: (1) Following routine culture in Dulbecco's modified eagle medium, primary PC12 cells were stimulated under LF-PEF (pulse frequency 50.Hz, pulse width 20 μs, peak field strength 1 V/m) for 5, 10, 15, 20, and 30 minutes. (2) Inhibitors (H-89 or U0126, 1 μmol/L) were added 30 minutes before LF-PEF stimulation for 10 minutes. MAIN OUTCOME MEASURES: (1) TH expression was determined by Western blot in PC12 cells at 0.5, 1,2, 3, and 4 days after LF-PEF stimulation. Similarly, DA was measured by high-performance liquid chromatography in media at 2, 3, 4, or 5 days after LF-PEE (2) TH expression was detected 1 day after H-89 or U0126 treatment and LF-PEE RESULTS: (1) Short-term LF-PEF stimulation (5 and 10 minutes) increased TH expression and media DA levels after short-term culture (2 days) (P 〈 0.01), but both parameters decreased with longer culture (3 4 days) (P 〈 0.01). Long-term LF-PEF stimulation (15, 20, or 30 minutes) decreased TH and DA synthesis, followed by a rapid increase (P 〈 0.01). (2) H89 could completely inhibit TH expression in PC12 cells stimulated by LF-PEF for 10 minutes, while the inhibition rate of U0126 was 53.2%. CONCLUSION: Short-term LF-PEF first promotes then inhibits, while long-term LF-PEF first inhibits then promotes, TH and DA synthesis. LF-PEF stimulation regulates TH expression primarily by activating protein kinase A to regulate DA synthesis.