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Experimental and Molecular Pathology Apr 2022Neutrophils stand sentinel over infection and possess diverse antimicrobial weapons, including neutrophil extracellular traps (NETs). NETs are composed of web-like...
Neutrophils stand sentinel over infection and possess diverse antimicrobial weapons, including neutrophil extracellular traps (NETs). NETs are composed of web-like extracellular DNA decorated with antimicrobial substances and can trap and eliminate invading microorganisms. Although phorbol 12-myristate 13-acetate (PMA) is a potent NET inducer, previous studies have demonstrated that not all neutrophils exhibit NET formation even if stimulated by PMA at high concentrations. This study first showed that some neutrophils stimulated by PMA displayed a swollen nucleus but not NET formation and that hypoxic environments suppressed the NET release. Next, characterization of PMA-stimulated neutrophils with a swollen nucleus was accomplished by differentiating between suicidal-type NETosis and apoptosis. Furthermore, the significance of the phenomenon was examined using formalin-fixed, paraffin-embedded human lung disease tissues with and without pneumonia. As a result, histone H3 citrullination, DNA outflow, propidium iodide labeling, resistance to DNase I, and suspended actin rearrangement were characteristics of PMA-stimulated neutrophils with a swollen nucleus distinct from neutrophils that underwent either suicidal-type NETosis or apoptosis. Neutrophils stimulated by PMA under hypoxic conditions secreted matrix metalloproteinase-9 cytotoxic to human lung-derived fibroblasts. Further, deposition of neutrophil-derived citrullinated histone H3 chromatin substances in pulmonary lesions was greater in patients with pneumonia than in patients without pneumonia and positively correlated with hypoxia-inducible factor-1α expression. The collective findings suggested that neutrophils activated under hypoxic conditions could be putative modulators of hypoxia-related disease manifestations.
Topics: Acetates; DNA; Extracellular Traps; Histones; Humans; Hypoxia; Lung Diseases; Myristic Acid; Neutrophils; Phorbols; Tetradecanoylphorbol Acetate
PubMed: 35259405
DOI: 10.1016/j.yexmp.2022.104754 -
Biochemical and Biophysical Research... Nov 1980
Topics: Animals; Animals, Newborn; Cells, Cultured; Enzyme Induction; Kinetics; Mice; Mice, Inbred BALB C; Phorbol Esters; Phorbols; Skin; Tetradecanoylphorbol Acetate; gamma-Glutamyltransferase
PubMed: 6110426
DOI: 10.1016/0006-291x(80)90321-6 -
The Journal of Investigative Dermatology Jul 1983Stimulation of epidermal growth in adult mouse skin can be induced by chemical agents, such as phorbol esters and other skin mitogens, or by mechanical means, such as...
Stimulation of epidermal growth in adult mouse skin can be induced by chemical agents, such as phorbol esters and other skin mitogens, or by mechanical means, such as skin massage and skin wounding. It leads to different kinds of epidermal hyperproliferation, according to interference with mechanisms of endogenous growth control (G1 chalone) and to mediation by endogenous regulatory factors (prostaglandins). Certain phorbol esters and skin wounding induce epidermal hyperproliferation and, in addition, a metaplastic process. Another property of these metaplasiogenic mitogens is their tumor-promoting efficacy in mouse skin, which has been initiated by a carcinogen in a subthreshold dose. Tailor-made phorbol esters allow the subdivision of the process of tumor promotion into two stages. In the first--probably irreversible--stage, a single application of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) or wounding brings about the events critical and obligatory for promotion, whereas in the second--probably reversible--stage, repetitive applications of an "incomplete promoter" evoke epidermal hyperplasia necessary to make the tumors visible. Adult guinea pig epidermis in vivo, as well as primary cell cultures derived from adult guinea pig ear epidermis, responds to the proliferative effects of phorbol esters such as TPA along a similar sequence of biochemical events as mouse skin in vivo. The in vitro approach allows the study of the molecular events involved in the mechanism of action of phorbol esters in more detail.
Topics: Animals; Cell Division; Cell Transformation, Neoplastic; Mice; Phorbol Esters; Phorbols; Prostaglandins; Skin; Tetradecanoylphorbol Acetate
PubMed: 6863986
DOI: 10.1111/1523-1747.ep12540971 -
Cell Calcium 2003We have studied the modulation of gating properties of the Ca2+-permeable, cation channel TRPV4 transiently expressed in HEK293 cells. The phorbol ester 4alphaPDD...
We have studied the modulation of gating properties of the Ca2+-permeable, cation channel TRPV4 transiently expressed in HEK293 cells. The phorbol ester 4alphaPDD transiently activated a current through TRPV4 in the presence of extracellular Ca2+. Increasing the concentration of extracellular Ca2+ ([Ca2+](e)) reduced the current amplitude and accelerated its decay. This decay was dramatically delayed in the absence of [Ca2+](e). It was also much slower in the presence of [Ca2+](e) in a mutant channel, obtained by a point mutation in the 6th transmembrane domain, F707A. Mutant channels, containing a single mutation in the C-terminus of TRPV4 (E797), were constitutively open. In conclusion, gating of the 4alphaPDD-activated TRPV4 channel depends on both extra- and intracellular Ca2+, and is modulated by mutations of single amino acid residues in the 6th transmembrane domain and the C-terminus of the TRPV4 protein.
Topics: Amino Acid Substitution; Cation Transport Proteins; Cations; Cells, Cultured; Electrophysiology; Extracellular Space; Humans; Intercellular Junctions; Ion Channel Gating; Ion Channels; Mutation; Phorbols; TRPV Cation Channels
PubMed: 12765694
DOI: 10.1016/s0143-4160(03)00064-2 -
Proceedings of the National Academy of... May 1984Solubilized lectin-purified extracts from human monocyte-like cells (U-937) and freshly isolated human mononuclear cells preincubated in the presence of phorbol...
Solubilized lectin-purified extracts from human monocyte-like cells (U-937) and freshly isolated human mononuclear cells preincubated in the presence of phorbol 12-myristate 13-acetate (PMA) stimulated phosphorylation of synthetic tyrosine-containing polymers and of casein. Tyrosine phosphorylation was confirmed by phospho amino acid analysis. PMA stimulated phosphorylation of exogenous substrates in a time- and concentration-dependent manner. This phosphorylation reaction did not require addition of phospholipid, diolein, or calcium. Biologically inactive phorbol compounds did not stimulate phosphorylation in this system. In addition, PMA enhanced phosphorylation of a Mr approximately equal to 140,000 protein as well as several other endogenous proteins in the U-937 extracts. PMA treatment stimulated predominantly phosphorylation on tyrosine residues of the Mr 140,000 protein. Tyrosine phosphorylation, typical of growth-promoting peptides such as insulin or epidermal growth factor, is believed to play a role in regulating normal and disordered cellular growth and proliferation. The demonstration of PMA-stimulated tyrosine phosphorylation might provide a clue to the mechanism of cellular differentiation and proliferation induced by the tumor promoter.
Topics: Cells, Cultured; Humans; Monocytes; Phorbol Esters; Phorbols; Phosphorylation; Phosphotyrosine; Protein Kinases; Protein-Tyrosine Kinases; Tetradecanoylphorbol Acetate; Tyrosine
PubMed: 6201862
DOI: 10.1073/pnas.81.9.2762 -
Journal of the National Cancer Institute Nov 1976Dose-response relationships on the abilities of several phorbol ester tumor promoters to promote skin tumors after 7,12-dimethylbenz[a]anthracene initiation and to bring...
Dose-response relationships on the abilities of several phorbol ester tumor promoters to promote skin tumors after 7,12-dimethylbenz[a]anthracene initiation and to bring about edema, inflammation, and epidermal hyperplasia were determined in female Charles River CD-1 mice. The promoting ability of the potent synthetic promoter, phorbol-12,13-dioctanoate (PdiC8), was determined over a dose range of 0.1-10 mug/application. Administration of PdiC8 two times weekly at dosages of 4, 6, 8, and 10 mug gave little variation in tumor response. A dose-dependent tumor response occurred at doses of 1-4 mug PdiC8. Only 1 papilloma was observed when PdiC8 was given twice weekly at a dose of 0.1 or 0.5 mug. A similar dose-response relation was observed for the ability of PdiC8 to stimulate epidermal hyperplasia. Investigations of other phorbol esters revealed an excellent correlation between their promoting ability and their ability to induce epidermal hyperplasia; however, that was not the case for compounds outside the phorbol ester series (i.e., acetic acid, cantharidin, and ethylphenylpropiolate).
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Cell Division; Dose-Response Relationship, Drug; Drug Synergism; Edema; Female; Hyperplasia; Inflammation; Mice; Neoplasms, Experimental; Papilloma; Phorbol Esters; Phorbols; Skin; Skin Neoplasms; Tetradecanoylphorbol Acetate
PubMed: 826651
DOI: 10.1093/jnci/57.5.1145 -
Science (New York, N.Y.) Nov 1979Wild-type Chinese hamster V79 cells (6-thioguanine-sensitive) reduce the recovery of 6-thioguanine-resistant cells when they are cultured together at high densities,...
Wild-type Chinese hamster V79 cells (6-thioguanine-sensitive) reduce the recovery of 6-thioguanine-resistant cells when they are cultured together at high densities, through a form of intercellular communication (metabolic cooperation). Cooperation is inhibited by 12-O-tetradecanoyl phorbol-13-acetate, rescuing the 6-thioguanine-resistant cells. These results may be useful in the study of an aspect of the mechanism of tumor promotion and in assaying for promoters.
Topics: Animals; Cell Communication; Cell Membrane; Cricetinae; Dose-Response Relationship, Drug; Drug Resistance; Phorbol Esters; Phorbols; Structure-Activity Relationship; Tetradecanoylphorbol Acetate; Thioguanine
PubMed: 493994
DOI: 10.1126/science.493994 -
Science (New York, N.Y.) Apr 1983By means of a two-stage promotion protocol in mouse epidermis with 12-O-tetradecanoylphorbol-13-acetate as first-stage promoter and 12-O-retinoylphorbol-13-acetate as...
By means of a two-stage promotion protocol in mouse epidermis with 12-O-tetradecanoylphorbol-13-acetate as first-stage promoter and 12-O-retinoylphorbol-13-acetate as second-stage promoter, the effects of the former that are critical and obligatory for tumor promotion were shown to be irreversible in nature for at least 8 weeks. The reversibility of tumor promotion was related to the second stage of promotion, reflecting the reversibility of epidermal hyperplasia induced by 12-O-tetradecanoylphorbol-13-acetate.
Topics: Animals; Carcinogens; Cell Line; Epidermis; Female; Hyperplasia; Mice; Mice, Inbred Strains; Neoplasms, Experimental; Phorbol Esters; Phorbols; Precancerous Conditions; Skin Neoplasms; Tetradecanoylphorbol Acetate; Time Factors
PubMed: 6828884
DOI: 10.1126/science.6828884 -
Proceedings of the National Academy of... Mar 1979Human promyelocytic leukemia cells (HL-60) were induced to differentiate into mature cells by the tumor-promoting agent phorbol-12-myristate-13-acetate and other related...
Human promyelocytic leukemia cells (HL-60) were induced to differentiate into mature cells by the tumor-promoting agent phorbol-12-myristate-13-acetate and other related phorbol diesters. Differentiation was determined by an increase in the percent of myelocytes, metamyelocytes, and other mature myeloid cells as well as by an increase in the percent of phagocytizing cells. Induction of differentiation could be determined after 2 days of treatment with phorbol-12-myristate-13-acetate at a dose as low as 6 X 10(11) M. A correlation was found between reported tumor-promoting activity of a series of phorbol esters and their ability to induce myeloid differentiation and to inhibit cell growth. It is suggested that tumor-promoting agents like chemicals that induce terminal differentiation in these cells, at extremely low concentrations, may be used as a tool in the study of the control of cell growth, cell differentiation, and malignancy in human leukemic cells.
Topics: Cell Differentiation; Cell Division; Cell Line; Humans; Kinetics; Leukemia, Myeloid; Phagocytosis; Phorbol Esters; Phorbols; Structure-Activity Relationship
PubMed: 286311
DOI: 10.1073/pnas.76.3.1293 -
The Journal of Biological Chemistry Jul 1982Tumor-promoting phorbol esters such as 12-O-tetradecanoylphorbol-13-acetate (TPA) directly activate in vitro Ca2+-activated, phospholipid-dependent protein kinase...
Tumor-promoting phorbol esters such as 12-O-tetradecanoylphorbol-13-acetate (TPA) directly activate in vitro Ca2+-activated, phospholipid-dependent protein kinase (protein kinase C), which normally requires unsaturated diacylglycerol. Kinetic analysis indicates that TPA can substitute for diacylglycerol and greatly increases the affinity of the enzyme for Ca2+ as well as for phospholipid. Under physiological conditions, the activation of this enzyme appears to be linked to the receptor-mediated phosphatidylinositol breakdown which may be provoked by a wide variety of extracellular messengers, eventually leading to the activation of specific cellular functions or proliferation. Using human platelets as a model system, TPA is shown to enhance the protein kinase C-specific phosphorylation associated with the release reaction in the total absence of phosphatidylinositol breakdown. Various phorbol derivatives which have been shown to be active in tumor promotion are also capable of activating this protein kinase in in vitro systems.
Topics: Animals; Blood Platelets; Blood Proteins; Brain; Calcium; Enzyme Activation; Kinetics; Phorbols; Phospholipids; Phosphorylation; Protein Kinases; Rats; Tetradecanoylphorbol Acetate
PubMed: 7085651
DOI: No ID Found