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Lee CH, Tsao YH, Weng YP, Wang IC, Chen YP, Hung PF. Therapeutic Effects of Perilla Phenols in Oral Squamous Cell Carcinoma. Int J Mol Sci 2023; 24:14931. [PMID: 37834377 PMCID: PMC10573788 DOI: 10.3390/ijms241914931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 10/15/2023] Open
Abstract
The herbal medicine perilla leaf extract (PLE) exhibits various pharmacological properties. We showed that PLE inhibits the viability of oral squamous cell carcinoma (OSCC) cells. HPLC analysis revealed that caffeic acid (CA) and rosmarinic acid (RA) are the two main phenols in PLE, and reduced OSCC cell viability in a dose-dependent manner. The optimal CA/RA combination ratio was 1:2 at concentrations of 300-500 μM but had no synergistic inhibitory effect on the viability of OSCC cells. CA, RA, or their combination effectively suppressed interleukin (IL)-1β secretion by OSCC OC3 cells. Long-term treatment with CA and CA/RA mixtures, respectively, induced EGFR activation, which might cause OC3 cells to become EGFR-dependent and consequently increased the sensitivity of OC3 cells to a low dose (5 μM) of the EGFR tyrosine kinase inhibitor gefitinib. Chronic treatment with CA, RA, or their combination exhibited an inhibitory effect more potent than that of low-dose (1 μM) cisplatin on the colony formation ability of OSCC cells; this may be attributed to the induction of apoptosis by these treatments. These findings suggest that perilla phenols, particularly CA and RA, can be used as adjuvant therapies to improve the efficacy of chemotherapy and EGFR-targeted therapy in OSCC.
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Affiliation(s)
- Chia-Huei Lee
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 35053, Taiwan; (Y.-H.T.); (Y.-P.C.); (P.-F.H.)
| | - Yu-Hsin Tsao
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 35053, Taiwan; (Y.-H.T.); (Y.-P.C.); (P.-F.H.)
- Department of Life Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Yui-Ping Weng
- Department of Acupressure Technology, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan;
| | - I-Ching Wang
- Department of Life Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Yao-Ping Chen
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 35053, Taiwan; (Y.-H.T.); (Y.-P.C.); (P.-F.H.)
| | - Pin-Feng Hung
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 35053, Taiwan; (Y.-H.T.); (Y.-P.C.); (P.-F.H.)
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Chan CH, Lin P, Yang TY, Bao BY, Jhong JY, Weng YP, Lee TH, Cheng HF, Lu TL. Epithelial polarization in the 3D matrix requires MST3 signaling to regulate ZO-1 position. PLoS One 2023; 18:e0285217. [PMID: 37155619 PMCID: PMC10166550 DOI: 10.1371/journal.pone.0285217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 04/17/2023] [Indexed: 05/10/2023] Open
Abstract
Apical-basal cell polarity must be tightly controlled for epithelial cyst and tubule formation, and these are important functional units in various epithelial organs. Polarization is achieved through the coordination of several molecules that divide cells into an apical domain and a basolateral domain, which are separated from tight and adherens junctions. Cdc42 regulates cytoskeletal organization and the tight junction protein ZO-1 at the apical margin of epithelial cell junctions. MST kinases control organ size through the regulation of cell proliferation and cell polarity. For example, MST1 relays the Rap1 signal to induce cell polarity and adhesion of lymphocytes. Our previous study showed that MST3 was involved in E-cadherin regulation and migration in MCF7 cells. In vivo, MST3 knockout mice exhibited higher ENaC expression at the apical site of renal tubules, resulting in hypertension. However, it was not clear whether MST3 was involved in cell polarity. Here, control MDCK cells, HA-MST3 and HA-MST3 kinase-dead (HA-MST3-KD) overexpressing MDCK cells were cultured in collagen or Matrigel. We found that the cysts of HA-MST3 cells were fewer and smaller than those of control MDCK cells; ZO-1 was delayed to the apical site of cysts and in cell-cell contact in the Ca2+ switch assay. However, HA-MST3-KD cells exhibited multilumen cysts. Intensive F-actin stress fibers were observed in HA-MST3 cells with higher Cdc42 activity; in contrast, HA-MST3-KD cells had lower Cdc42 activity and weaker F-actin staining. In this study, we identified a new MST3 function in the establishment of cell polarity through Cdc42 regulation.
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Affiliation(s)
- Chee-Hong Chan
- Department of Nephrology, Chang Bing Show Chwan Memorial Hospital, Lukang, Changhua, Taiwan
| | - Pei Lin
- Division of Cardiology, Department of Internal Medicine, An Nan Hospital, China Medical University, Tainan, Taiwan
| | - Tse-Yen Yang
- Molecular and Genomic Epidemiology Center, Department of Medical Research, China Medical University, Tainan, Taiwan
| | - Bo-Ying Bao
- College of School of Pharmacy, China Medical University, Tainan, Taiwan
| | - Jhen-Yang Jhong
- Department of Medical Laboratory Science and Biotechnology, Sin-Lau Hospital, Tainan, Taiwan
| | - Yui-Ping Weng
- Department of Acupressure Technology, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Te-Hsiu Lee
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Hui-Fen Cheng
- Department of Laboratory Medicine, Tainan Municipal Hospital (Managed by Show Chwan Medical Care Corporation), Tainan, Taiwan
| | - Te-Ling Lu
- College of School of Pharmacy, China Medical University, Tainan, Taiwan
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Lu TJ, Kan WC, Yang SS, Jiang ST, Wu SN, Ling P, Bao BY, Lin CY, Yang ZY, Weng YP, Chan CH, Lu TL. MST3 is involved in ENaC-mediated hypertension. Am J Physiol Renal Physiol 2019; 317:F30-F42. [PMID: 30969802 DOI: 10.1152/ajprenal.00455.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Liddle syndrome is an inherited form of human hypertension caused by increasing epithelial Na+ channel (ENaC) expression. Increased Na+ retention through ENaC with subsequent volume expansion causes hypertension. In addition to ENaC, the Na+-K+-Cl- cotransporter (NKCC) and Na+-Cl- symporter (NCC) are responsible for Na+ reabsorption in the kidneys. Several Na+ transporters are evolutionarily regulated by the Ste20 kinase family. Ste20-related proline/alanine-rich kinase and oxidative stress-responsive kinase-1 phosphorylate downstream NKCC2 and NCC to maintain Na+ and blood pressure (BP) homeostasis. Mammalian Ste20 kinase 3 (MST3) is another member of the Ste20 family. We previously reported that reduced MST3 levels were found in the kidneys in spontaneously hypertensive rats and that MST3 was involved in Na+ regulation. To determine whether MST3 is involved in BP stability through Na+ regulation, we generated a MST3 hypomorphic mutation and designated MST3+/- and MST3-/- mice to examine BP and serum Na+ and K+ concentrations. MST3-/- mice exhibited hypernatremia, hypokalemia, and hypertension. The increased ENaC in the kidney played roles in hypernatremia. The reabsorption of more Na+ promoted more K+ secretion in the kidney and caused hypokalemia. The hypernatremia and hypokalemia in MST3-/- mice were significantly reversed by the ENaC inhibitor amiloride, indicating that MST3-/- mice reabsorbed more Na+ through ENaC. Furthermore, Madin-Darby canine kidney cells stably expressing kinase-dead MST3 displayed elevated ENaC currents. Both the in vivo and in vitro results indicated that MST3 maintained Na+ homeostasis through ENaC regulation. We are the first to report that MST3 maintains BP stability through ENaC regulation.
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Affiliation(s)
- Te-Jung Lu
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology , Tainan , Taiwan
| | - Wei-Chih Kan
- Department of Nephrology, Chi-Mei Medical Center , Tainan , Taiwan.,Department of Biological Science and Technology, Chung Hwa University of Medical Technology , Tainan , Taiwan
| | - Sung-Sen Yang
- Division of Nephrology, Department of Medicine, Tri-service General Hospital, Graduate Institute of Medical Sciences, National Defense Medical Center , Taipei , Taiwan
| | - Si-Tse Jiang
- Department of Research and Development, National Laboratory Animal Center, National Applied Research Laboratories , Tainan , Taiwan
| | - Sheng-Nan Wu
- Department of Physiology, College of Medicine, National Cheng Kung University , Tainan , Taiwan
| | - Pin Ling
- Department of Physiology, College of Medicine, National Cheng Kung University , Tainan , Taiwan.,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University , Tainan , Taiwan
| | - Bo-Ying Bao
- School of Pharmacy, China Medical University , Taichung , Taiwan
| | - Chia-Yu Lin
- Department of Medical Laboratory Science and Biotechnology, China Medical University , Taichung , Taiwan
| | - Zin-Ya Yang
- Department of Medical Laboratory Science and Biotechnology, China Medical University , Taichung , Taiwan
| | - Yui-Ping Weng
- Department of Biological Science and Technology, Chung Hwa University of Medical Technology , Tainan , Taiwan
| | - Chee-Hong Chan
- Department of Nephrology, Chang Bing Show Chwan Memorial Hospital, Lukang, Changhua, Taiwan
| | - Te Ling Lu
- School of Pharmacy, China Medical University , Taichung , Taiwan
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Liu YH, Weng YP, Tsai HY, Chen CJ, Lee DY, Hsieh CL, Wu YC, Lin JY. Aqueous extracts of Paeonia suffruticosa modulates mitochondrial proteostasis by reactive oxygen species-induced endoplasmic reticulum stress in pancreatic cancer cells. Phytomedicine 2018; 46:184-192. [PMID: 30097117 DOI: 10.1016/j.phymed.2018.03.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 02/09/2018] [Accepted: 03/17/2018] [Indexed: 05/27/2023]
Abstract
BACKGROUND Pancreatic cancer (PC) remains the leading cause of cancer mortality, with limited therapeutic targets, and alterations in endoplasmic reticulum (ER)-related proteostasis may be a potential target for therapy. The root bark of Paeonia suffruticosa has been shown to inhibit cancer growth and metastasis, although its impact on PC is unknown. PURPOSE To ascertain the anti-cancer effects of P. suffruticosa on oncogenic functions of PC and determine the detailed molecular mechanisms. STUDY DESIGN Efficacy assessment of extracts, in vitro using PC cells as a model system and in vivo in mouse xenograft tumors. METHODS P. suffruticosa aqueous extracts (PS) were prepared and assessed using liquid chromatography-tandem mass spectrometry. Cell viability, proteins, and cell components were measured using MTT assay, western blotting, and immunofluorescence. Cell apoptosis, cell cycle, and migration were assessed using colorimetric assays, fluorescence activated cell sorting, and transwell migration. Reactive oxygen species (ROS) were evaluated with a commercial 2'-7'-dichlorofluorescin diacetate kit. For the xenograft model, AsPC1 cells were inoculated subcutaneously into immunocompromised mice and PS (oral) was administered over 3 weeks with or without gemcitabine (GEM, intraperitoneal), a first-line advanced/metastatic PC therapy. RESULTS PS stimulated ER stress and affected mitochondrial membrane potential to increase autophagosome numbers and block their degradation, followed by autophagy induction and finally cell apoptosis. Additionally, PS-mediated proteostasis impairment resulted in altered dynamics of the actin cytoskeleton, cell motility impairment, and cell cycle progression inhibition. Conversely, a ROS scavenger partially reversed PS-mediated degradation of peptidyl-prolyl cis-trans isomerase B (PPIB), an ER protein important for protein folding, suggesting that ROS generation by PS may be the upstream of PS-triggering of mitophagy and final cell apoptosis. Nevertheless, oral administration of PS, alone or in combination with GEM, delayed tumor growth in a xenograft model without affecting body weight. CONCLUSION These findings indicate that PS may constitute a potential new alternative or complementary medicine for PC.
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Affiliation(s)
- Yu-Huei Liu
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan; Department of Medical Genetics and Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Yui-Ping Weng
- Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Hsin-Ying Tsai
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan; Department of Medical Genetics and Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Chao-Jung Chen
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
| | - Der-Yen Lee
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
| | - Ching-Liang Hsieh
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan; Department of Chinese Medicine, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Research Center for Chinese Medicine and Acupuncture, China Medical University, Taichung, Taiwan
| | - Yang-Chang Wu
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; Research Center for Natural Products & Drug Development, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung, Taiwan
| | - Jung-Yaw Lin
- Department of Life Science, National Taiwan Normal University, No. 88, Ting-Chow Road, Section 4, Taipei, Taiwan; Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan.
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Weng YP, Hung PF, Ku WY, Chang CY, Wu BH, Wu MH, Yao JY, Yang JR, Lee CH. The inhibitory activity of gallic acid against DNA methylation: application of gallic acid on epigenetic therapy of human cancers. Oncotarget 2017; 9:361-374. [PMID: 29416619 PMCID: PMC5787471 DOI: 10.18632/oncotarget.23015] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 11/13/2017] [Indexed: 12/22/2022] Open
Abstract
Epigenome aberrations have been observed in tobacco-associated human malignancies. (−)-epigallocatechin-3-gallate (EGCG) has been proven to modulate gene expression by targeting DNA methyltransferases (DNMTs) through a proposed mechanism involving the gallate moiety of EGCG. We show that gallic acid (GA) changes the methylome of lung cancer and pre-malignant oral cell lines and markedly reduces both nuclear and cytoplasmic DNMT1 and DNMT3B within 1 week. GA exhibits stronger cytotoxicity against the lung cancer cell line H1299 than EGCG. We found that GA reactivates the growth arrest and DNA damage-inducible 45 (GADD45) signaling pathway may through the demethylation of CCNE2 and CCNB1 in H1299 cells. To improve the epigenetic anti-cancer activities of oolong tea, we identified a fungus, Aspergillus sojae which can efficiently increase the GA content in oolong tea via a 2-week fermentation process. The fungus dramatically increased GA up to 44.8 fold in the post-fermentation oolong tea extract (PFOTE), resulting in enhanced demethylation effects and a significant reduction in the nuclear abundances of DNMT1, DNMT3A, and DNMT3B in lung cancer cell lines. PFOTE also showed stronger anti-proliferation activities than oolong tea extract (OTE) and increased sensitivity to cisplatin in H1299 cells. In summary, we demonstrate the potent inhibitory effects of GA on the activities of DNMTs and provide a strong scientific foundation for the use of specialized fermented oolong tea high in GA as an effective dietary intervention strategy for tobacco-associated cancers.
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Affiliation(s)
- Yui-Ping Weng
- Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Pin-Feng Hung
- National Institute of Cancer Research, National Health Research Institutes, Zhunan, Taiwan
| | - Wen-Yen Ku
- Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Chang-Yuan Chang
- Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Bo-Han Wu
- Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Ming-Han Wu
- Graduate Institute of Biomedical Science, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Jau-Ying Yao
- National Institute of Cancer Research, National Health Research Institutes, Zhunan, Taiwan
| | - Ji-Rui Yang
- National Institute of Cancer Research, National Health Research Institutes, Zhunan, Taiwan
| | - Chia-Huei Lee
- National Institute of Cancer Research, National Health Research Institutes, Zhunan, Taiwan
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Liu YH, Weng YP, Lin HY, Tang SW, Chen CJ, Liang CJ, Ku CY, Lin JY. Aqueous extract of Polygonum bistorta modulates proteostasis by ROS-induced ER stress in human hepatoma cells. Sci Rep 2017; 7:41437. [PMID: 28134285 PMCID: PMC5278379 DOI: 10.1038/srep41437] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 12/16/2016] [Indexed: 01/16/2023] Open
Abstract
Hepatocellular carcinoma (HCC) remains the leading cause of cancer mortality with limited therapeutic targets. The endoplasmic reticulum (ER) plays a pivotal role in maintaining proteostasis in normal cells. However, alterations in proteostasis are often found in cancer cells, making it a potential target for therapy. Polygonum bistorta is used in traditional Chinese medicine owing to its anticancer activities, but the molecular and pharmacological mechanisms remain unclear. Using hepatoma cells as a model system, this study demonstrated that P. bistorta aqueous extract (PB) stimulated ER stress by increasing autophagosomes but by blocking degradation, followed by the accumulation of ubiquitinated proteins and cell apoptosis. In addition, an autophagy inhibitor did not enhance ubiquitinated protein accumulation whereas a reactive oxygen species (ROS) scavenger diminished both ubiquitinated protein accumulation and ligand-stimulated epidermal growth factor receptor (EGFR) expression, suggesting that ROS generation by PB may be upstream of PB-triggered cell death. Nevertheless, PB-exerted proteostasis impairment resulted in cytoskeletal changes, impairment of cell adhesion and motility, and inhibition of cell cycle progression. Oral administration of PB delayed tumour growth in a xenograft model without significant body weight loss. These findings indicate that PB may be a potential new alternative or complementary medicine for HCC.
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Affiliation(s)
- Yu-Huei Liu
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, 404, Taiwan.,Department of Medical Genetics and Medical Research, China Medical University Hospital, Taichung, 404, Taiwan
| | - Yui-Ping Weng
- Graduate Institute of Biological Science and Technology, Chung Hwa University of Medical Technology, Tainan, 717, Taiwan.,Department of Biological Science and Technology, Chung Hwa University of Medical Technology, Tainan, 717, Taiwan
| | - Hsuan-Yuan Lin
- Department of Life Science, National Taiwan Normal University, Taipei, 116, Taiwan
| | - Sai-Wen Tang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Chao-Jung Chen
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, 404, Taiwan
| | - Chi-Jung Liang
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Chung-Yu Ku
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Jung-Yaw Lin
- Department of Life Science, National Taiwan Normal University, Taipei, 116, Taiwan.,Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
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Kan WC, Lu TL, Ling P, Lee TH, Cho CY, Huang CYF, Jeng WY, Weng YP, Chiang CY, Wu JB, Lu TJ. Pervanadate induces Mammalian Ste20 Kinase 3 (MST3) tyrosine phosphorylation but not activation. J Inorg Biochem 2016; 160:33-9. [PMID: 27118027 DOI: 10.1016/j.jinorgbio.2016.04.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 04/08/2016] [Accepted: 04/12/2016] [Indexed: 11/18/2022]
Abstract
The yeast Ste20 (sterile) protein kinase, which is a serine/threonine kinase, responds to the stimulation of the G proteincoupled receptor (GPCR) pheromone receptor. Ste20 protein kinase serves as the critical component that links signaling from the GPCR/G proteins to the mitogen-activated protein kinase (MAPK) cascade in yeast. The yeast Ste20p functions as a MAP kinase kinase kinase kinase (MAP4K) in the pheromone response. Ste20-like kinases are structurally conserved from yeast to mammals. The mechanism by which MAP4K links GPCR to the MAPK pathway is less clearly defined in vertebrates. In addition to MAP4K, the tyrosine kinase cascade bridges G proteins and the MAPK pathway in vertebrate cells. Mammalian Ste20 Kinase 3 (MST3) has been categorized into the Ste20 family and has been reported to function in the regulation of cell polarity and migration. However, whether MST3 tyrosine phosphorylation regulates diverse signaling pathways is unknown. In this study, the tyrosine phosphatase inhibitor pervanadate was found to induce MST3 tyrosine phosphorylation in intact cells, and the activity of tyrosine-phosphorylated MST3 was measured. This tyrosine-directed phosphorylation was independent of MST3 activity. Parameters including protein conformation, Triton concentration and ionic concentration influenced the sensitivity of MST3 activity. Taken together, our data suggests that the serine/threonine kinase MST3 undergoes tyrosinedirected phosphorylation. The tyrosine-phosphorylated MST3 may create a docking site for the structurally conserved SH2/SH3 (Src Homology 2 and 3) domains within the Src oncoprotein. The unusual tyrosinephosphorylated MST3 may recruit MST3 to various signaling components.
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Affiliation(s)
- Wei-Chih Kan
- Department of Nephrology, Chi-Mei Medical Center, Tainan 701, Taiwan; Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, Tainan 701, Taiwan
| | - Te-Ling Lu
- School of Pharmacy, Tsuzuki Institute for Traditional Medicine, China Medical University, Taichung 404, Taiwan
| | - Pin Ling
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Te-Hsiu Lee
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, Tainan 701, Taiwan
| | - Chien-Yu Cho
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Chi-Ying F Huang
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei 112, Taiwan
| | - Wen-Yih Jeng
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Yui-Ping Weng
- Graduate Institute of Biological Science and Technology, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Chun-Yen Chiang
- Department of Cardiology, Chi-Mei Medical Center, Tainan, Taiwan; Department of Optometry, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Jin Bin Wu
- School of Pharmacy, Tsuzuki Institute for Traditional Medicine, China Medical University, Taichung 404, Taiwan
| | - Te-Jung Lu
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, Tainan 701, Taiwan.
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Abstract
Volvatoxin A2 (VVA2), a novel pore-forming cardiotoxic protein was isolated from the mushroom Volvariella volvacea. We identified an N-terminal fragment (NTF) (1-127 residues) of VVA2 as a domain for oligomerization by limited tryptic digestion. On preincubation of NTF with VVA2, NTF was found to inhibit VVA2 hemolytic activity by inducing VVA2 oligomerization in the solution in the same manner as liposomes. By site-directed mutagenesis, the amphipathic alpha-helix B of NTF or VVA2 was shown to be indispensable for its biological functions. Interestingly, at a molar ratio of recombinant NTF (reNTF)/VVA2 as low as 0.01, reNTF was able to inhibit VVA2 hemolytic activity and induce VVA2 oligomerization. This indicates that reNTF can trigger VVA2 oligomerization by a seeding effect. Furthermore, the recombinant C-terminal fragment (128-199 residues) was found to be a functional domain that mediates the membrane binding of VVA2. We found a fragment localized at the C-terminal half of VVA2 containing beta6, -7, and -8, which is protected from protease digestion because of its insertion of a membrane. We also identified a putative heparin binding site (HBS) located in the VVA2 C terminus (166-194 residues), which was conserved among 10 kinds of snake venom cardiotoxins. VVA2 or the reHBS fragment was shown to interact with sulfated glycoaminoglycans by affinity column chromatography. The finding of a higher number of glycoaminoglycans in the membrane of cardiac myocytes suggested that they could be the specific membrane target for VVA2. Taken together, these findings indicate that VVA2 contains two functional domains, NTF and CTF. The NTF domain is responsible for VVA2 oligomerization and the CTF domain for membrane binding and insertion. Our results support a model whereby the formation of VVA2 oligomeric pre-pore complexes precedes their membrane insertion.
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Affiliation(s)
- Yui-Ping Weng
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10081, Taiwan, Republic of China
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Tien YC, Chih HW, Cheng YM, Su JY, Weng YP, Lin SY. The influence of the gap size on the interfacial union between the bone and the tendon. Kaohsiung J Med Sci 1999; 15:581-8. [PMID: 10603705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
An in-vivo model of New Zealand white rabbit was used to study the influence of gap size on the interfacial union between bone and tendon through histological observation and mechanical testing. In the model, the anterior cruciate ligament (ACL) was cut and reconstructed by autografted semitendinosus tendon (with average diameter of 1.48 mm +/- 0.12 mm). Mechanical testing of the interfacial healing tissue was done on the 15th post-operative day. At that time the mean maximal tensile strength was 2.511 +/- 0.293 kg to a bone tunnel size of 1.5 mm. The maximal tensile strength lowered to 1.853 +/- 0.563 kg to a bone tunnel size of 1.8 mm. The maximal tensile strength lowered to 1.302 +/- 0.657 kg to a bone tunnel size of 2.0 mm. Using a paired-t test, the gap size was found to have great influence on the tensile strength of the interfacial healing tissue (p < 0.05). The histological study showed that the interfacial gap was connected by the new growing collagen fibers. The healing tissue appeared much denser and much more maturated and organized in the smaller interfacial gap in comparison with specimens with a larger gap so that it can tolerate higher tensile strength. From this study, we concluded that the gap size really plays an important role in the process of maturation and organization of interfacial healing tissue. Furthermore, we recommend that in order to achieve greater anchoring strength of the grafted tendons, the bone tunnel should be made with approximately the same diameter of grafted tendon.
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Affiliation(s)
- Y C Tien
- Department of Orthopaedic Surgery, Kaohsiung Medical University, Taiwan, Republic of China
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