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G D Niswender - One of the best experts on this subject based on the ideXlab platform.
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endocrine delivery of interferon tau protects the corpus luteum from Prostaglandin F2 alpha induced luteolysis in ewes
Biology of Reproduction, 2013Co-Authors: Alfredo Q Antoniazzi, Brett T Webb, Jared J Romero, Ryan L Ashley, Natalia P Smirnova, Luiz E Henkes, Rebecca C Bott, Joao Francisco Coelho De Oliveira, G D NiswenderAbstract:Paracrine release of ovine interferon tau (oIFNT) from the conceptus alters release of endometrial Prostaglandin F2 alpha (PGF) and prevents luteolysis. Endocrine release of oIFNT into the uterine vein occurs by Day 15 of pregnancy and may impart resistance of the corpus luteum (CL) to PGF. It was hypothesized that infusion of recombinant oIFNT (roIFNT) into the uterine or jugular veins on Day 10 of the estrous cycle would protect the CL against exogenous PGF-induced luteolysis. Osmotic pumps were surgically installed in 24 ewes to deliver bovine serum albumin (BSA; n ¼ 12) or roIFNT (200 lg/day; n ¼ 12) for 24 h into the uterine vein. Six ewes in each treatment group received a single injection of PGF (4 mg/58 kg body weight) 12 h after pump installation. In a second experiment, BSA or roIFNT was delivered at 20 or 200 lg/day into the uterine vein or 200 lg/day into the jugular vein for 72 h in 30 ewes. One half of these ewes received an injection of PGF 24 h after pump installation. Concentrations of progesterone in serum declined in BSAtreated ewes injected with PGF, but were sustained in all ewes infused with 20 lg/day of roIFNT into the uterine vein and 200 lg of roIFNT into the jugular vein followed 24 h later with injection of PGF. All concentrations of roIFNT and modes of delivery (uterine or jugular vein) increased luteal concentrations of IFN-stimulated gene (i.e., ISG15) mRNA. Infusion of 200 l go f IFNT over 24 h induced greater mRNA concentrations for cell survival genes, such as BCL2-like 1 (BCL2L1 or Bcl-xL), serine/ threonine kinase (AKT), and X-linked inhibitor of apoptosis (XIAP) and decreased Prostaglandin F receptor (PTGFR) mRNA concentrations, when compared to controls. It is concluded that endocrine delivery of roIFNT, regardless of route (uterine or jugular vein), effectively protects CL from the luteolytic actions of PGF by mechanisms that involve ISGs and stabilization of cell survival genes. corpus luteum, IFNT, ISG15, ovine, pregnancy, progesterone
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regulation of steady state concentrations of messenger ribonucleic acid encoding Prostaglandin F2 alpha receptor in ovine corpus luteum
Biology of Reproduction, 1996Co-Authors: Jennifer L Juengel, M C Wiltbank, Bernadette M Meberg, G D NiswenderAbstract:To investigate the regulation of ovine luteal receptors for Prostaglandin F2 alpha (PGF2 alpha), reverse transcription-polymerase chain reaction was used to produce a 284-bp partial cDNA that was 98% identical to that reported for the bovine PGF2 alpha receptor (PGF2 alpha-R). In situ hybridization localized mRNA for PGF2 alpha-R specifically to large luteal cells. In experiment 1, pools of luteal tissue (n = 4/day) collected from ewes on Days 3, 6, 9, 12, and 15 of the estrous cycle were analyzed for mRNA encoding PGF2 alpha-R. There was no difference in mean steady-state concentrations of mRNA encoding PGF2 alpha-R among any of the days studied (range = 2.3 +/- 0.3 to 3.5 +/- 0.7 fmol PGF2 alpha-R mRNA/ microgram poly[A]+ RNA as assessed by slot-blot hybridization). In experiment 2, ewes on Day 11 or Day 12 of the estrous cycle were administered PGF2 alpha, and corpora lutea were collected 4, 12, or 24 h later (n = 4-5 per time point). Nontreated (n = 4) or saline-treated (n = 4) ewes served as controls. Luteal concentrations of mRNA encoding PGF2 alpha-R were decreased (p < 0.05) at 4, 12, and 24 h after injection of PGF2 alpha. In experiment 3, ewes (midluteal phase) were administered saline, PGF2 alpha, phorbol 12-myristate 13-acetate (PMA), or LH via ovarian arterial injection, and luteal tissue was collected 0, 4, 12, or 24 h later (n = 3-4 per treatment per time). Steady-state concentrations of mRNA encoding PGF2 alpha-R were decreased (p < 0.05) by PGF2 alpha and PMA treatment (4 and 12 h) but were increased (p < 0.05) at 24 h after LH treatment. In summary, 1) mRNA encoding PGF2 alpha-R was localized to large luteal cells; 2) concentrations of mRNA encoding PGF2 alpha-R did not vary during the estrous cycle; 3) treatment with PGF2 alpha or PMA to activate protein kinase C decreased concentrations of PGF2 alpha-R mRNA within 4 h of treatment; and 4) administration LH increased concentrations of mRNA encoding PGF2 alpha-R 24 h following injection.
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protein kinase c second messenger system mediates the antisteroidogenic effects of Prostaglandin F2 alpha in the ovine corpus luteum in vivo
Biology of Reproduction, 1994Co-Authors: William J Mcguire, Jennifer L Juengel, G D NiswenderAbstract:Experiment I was designed to determine the optimal dose of phorbol 12-myristate 13-acetate (PMA) that inhibited progesterone production when infused into the ovarian artery. The most efficacious dose of PMA was 2 mumol. Experiment II was designed to determine whether activation of protein kinase C (PKC) inhibited progesterone production without initiating luteolysis. Ewes received ovarian arterial infusions of 4 alpha-phorbol (2 mumol, n = 4), PMA (2 mumol, n = 8), or Prostaglandin F2 alpha (PGF2 alpha; 1 mumol, n = 5). Concentrations of progesterone in serum decreased by 3 h in PMA-treated ewes and by 5 h in PGF2 alpha treated ewes (p < 0.05). By 48 h, serum levels of progesterone in PMA-treated ewes had returned to control values; but in PGF2 alpha-treated ewes they remained low for the duration of the experiment. Luteal weights and progesterone contents at 48 h were similar in 4 alpha-phorbol- and PMA-treated ewes but were decreased in PGF2 alpha-treated ewes (p < 0.05). Experiment III was designed to determine whether PGF2 alpha or PKC activation induced oligonucleosome formation or influenced mRNA levels for cytochrome P450sec or 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD). Ewes received treatments as in experiment II, and CL were collected at 3, 12, or 24 h (n = 3-4 per group). Luteal weights were decreased (p < 0.05) and oligonucleosome formation was increased (p < 0.05) in PGF2 alpha-treated ewes compared to controls or to PMA-treated ewes by 12 h.(ABSTRACT TRUNCATED AT 250 WORDS)
James D Lindsey - One of the best experts on this subject based on the ideXlab platform.
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induction of c fos by Prostaglandin F2 alpha in human ciliary smooth muscle cells
Investigative Ophthalmology & Visual Science, 1994Co-Authors: James D Lindsey, Robert N WeinrebAbstract:Purpose To evaluate the induction of the proto-oncogene c-fos in cultured human ciliary muscle cells by Prostaglandin F2 alpha (PGF2 alpha) by 17-phenyltrinor-PGF 2 alpha. Method Human ciliary muscle cells were grown to confluency in monolayer cell culture, placed in medium containing 1% fetal bovine serum for 5 days, treated by addition of PGF2 alpha or the trinor derivative, fixed, and then immunocytochemically stained using an antibody to c-Fos, the protein product of the translation of c-fos. Results After treatment with either agonist, the mean induction score (proportion of brightly immunostained nuclei) increased to a maximal level during the first hour and returned to basal levels 4 to 8 hours after treatment. Increasing the agonist concentration increased the maximal level, but had no effect on the time course of the response. The dose responses after 1 hour of treatment with PGF2 alpha or 17-phenyltrinor-PGF2 alpha increased similarly between 1.6 x 10(-9) M and 2 x 10(-7) M. When treated with 1 x 10(-6) M of either agonist, however, the induction was half that obtained at 2 x 10(-7) M. Conclusion Exposure of ciliary smooth muscle cells to either PGF2 alpha or 17-phenyltrinor-PGF2 alpha induces an immediate early gene expression response that is similar to c-Fos induction in other cell systems. These results establish the basis for future investigations evaluating the potential role of c-fos induction in mediating the effects of PGF2 alpha on uveoscleral outflow.
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propagation of ciliary smooth muscle cells in vitro and effects of Prostaglandin F2 alpha on calcium efflux
Investigative Ophthalmology & Visual Science, 1992Co-Authors: Robert N Weinreb, Dong Myung Kim, James D LindseyAbstract:The effect of Prostaglandin F2 alpha (PGF2 alpha) on calcium efflux from ciliary smooth muscle cells was studied. Ciliary smooth muscle cells, cultured from human ciliary muscle explants, retained the morphologic and immunologic characteristics of smooth muscle cells. High concentrations (to 10(-6) mol/l) of PGF2 alpha were associated with a dose-dependent increase of calcium (45Ca) efflux, whereas at concentrations lower than 10(-8) mol/l there was little or no 45Ca efflux. Our in vitro data are inconsistent with the experimental hypothesis that PGF2 alpha at pharmacologic concentrations relaxes ciliary muscle with a consequent increase in uveoscleral outflow.
Robert N Weinreb - One of the best experts on this subject based on the ideXlab platform.
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induction of c fos by Prostaglandin F2 alpha in human ciliary smooth muscle cells
Investigative Ophthalmology & Visual Science, 1994Co-Authors: James D Lindsey, Robert N WeinrebAbstract:Purpose To evaluate the induction of the proto-oncogene c-fos in cultured human ciliary muscle cells by Prostaglandin F2 alpha (PGF2 alpha) by 17-phenyltrinor-PGF 2 alpha. Method Human ciliary muscle cells were grown to confluency in monolayer cell culture, placed in medium containing 1% fetal bovine serum for 5 days, treated by addition of PGF2 alpha or the trinor derivative, fixed, and then immunocytochemically stained using an antibody to c-Fos, the protein product of the translation of c-fos. Results After treatment with either agonist, the mean induction score (proportion of brightly immunostained nuclei) increased to a maximal level during the first hour and returned to basal levels 4 to 8 hours after treatment. Increasing the agonist concentration increased the maximal level, but had no effect on the time course of the response. The dose responses after 1 hour of treatment with PGF2 alpha or 17-phenyltrinor-PGF2 alpha increased similarly between 1.6 x 10(-9) M and 2 x 10(-7) M. When treated with 1 x 10(-6) M of either agonist, however, the induction was half that obtained at 2 x 10(-7) M. Conclusion Exposure of ciliary smooth muscle cells to either PGF2 alpha or 17-phenyltrinor-PGF2 alpha induces an immediate early gene expression response that is similar to c-Fos induction in other cell systems. These results establish the basis for future investigations evaluating the potential role of c-fos induction in mediating the effects of PGF2 alpha on uveoscleral outflow.
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propagation of ciliary smooth muscle cells in vitro and effects of Prostaglandin F2 alpha on calcium efflux
Investigative Ophthalmology & Visual Science, 1992Co-Authors: Robert N Weinreb, Dong Myung Kim, James D LindseyAbstract:The effect of Prostaglandin F2 alpha (PGF2 alpha) on calcium efflux from ciliary smooth muscle cells was studied. Ciliary smooth muscle cells, cultured from human ciliary muscle explants, retained the morphologic and immunologic characteristics of smooth muscle cells. High concentrations (to 10(-6) mol/l) of PGF2 alpha were associated with a dose-dependent increase of calcium (45Ca) efflux, whereas at concentrations lower than 10(-8) mol/l there was little or no 45Ca efflux. Our in vitro data are inconsistent with the experimental hypothesis that PGF2 alpha at pharmacologic concentrations relaxes ciliary muscle with a consequent increase in uveoscleral outflow.
Ginette Serrero - One of the best experts on this subject based on the ideXlab platform.
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Abstract LB116: Prostaglandin F2 Receptor Negative Regulator (PTGFRN) is a novel target to inhibit tumor growth via antibody drug conjugate
Experimental and Molecular Therapeutics, 2021Co-Authors: Jorge Marquez, Jianping Dong, Chun Dong, Ginette SerreroAbstract:Introduction: Antibody-drug conjugates (ADC) are effective antibody-based therapeutics for a growing number of cancers, particularly hematopoietic and lymphoid tumors. There is need to identify new targets for ADCs, particularly for cancers with unmet needs. Methods: Our strategy has been to develop hybridoma libraries developed against cancer cells surface proteins and select antibody able to bind and internalize in cancer cell lines. Selected antibody can then be used for identification of the cancer cell surface target by immunoprecipitation (IP) and mass spectrometric analysis (Mass-spec), followed by target validation. After target validation, binding and target positivity can be tested by flow cytometry and western blot analysis on several cancer cell lines. The in vitro and in vivo efficacy of the antibody conjugated to a cytotoxic payload as ADC can then be evaluated with the target positive cancer cell lines.Results: Using the strategy described above, we have selected a monoclonal antibody named 33B7 able to bind and internalize in several cancer cell lines. The cell surface target binding 33B7 was identified by IP/Mass-spec as Prostaglandin F2 Receptor Negative Regulator (PTGFRN), a transmembrane protein in the Tetraspanin family. This target was then validated by showing that cells transfected with PTGFRN cDNA bound and internalized the antibody. Screening by Flow bidning and by western blot identified several human cancer cells lines expressing PTGFRN. In vitro treatment of these cell lines with the 33B7-saporin ADC inhibited their proliferation in a dose-dependent fashion. 33B7 conjugated to saporin was also able to block tumor growth in vivo in mouse xenografts when compared to a control ADC. Conclusion: These findings show that screening antibody libraries for internalizing antibodies in cancer cell lines is a good approach to identify new cancer targets for ADC development. These results suggest PTGFRN is a possible therapeutic target via antibody-based approach for certain cancers. The elucidation of PTGFRN role in cancer cells, particularly in possibly mediating metastasis is presently being carried out. Citation Format: Jorge Marquez, Jianping Dong, Chun Dong, Ginette Serrero. Prostaglandin F2 Receptor Negative Regulator (PTGFRN) is a novel target to inhibit tumor growth via antibody drug conjugate [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB116.
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Identification of Prostaglandin F2 Receptor Negative Regulator (PTGFRN) as an internalizable target in cancer cells for antibody-drug conjugate development.
PloS one, 2021Co-Authors: Jorge Marquez, Jianping Dong, Chun Dong, Changsheng Tian, Ginette SerreroAbstract:Antibody-drug conjugates (ADC) are effective antibody-based therapeutics for hematopoietic and lymphoid tumors. However, there is need to identify new targets for ADCs, particularly for solid tumors and cancers with unmet needs. From a hybridoma library developed against cancer cells, we selected the mouse monoclonal antibody 33B7, which was able to bind to, and internalize, cancer cell lines. This antibody was used for identification of the target by immunoprecipitation and mass spectrometric analysis, followed by target validation. After target validation, 33B7 binding and target positivity were tested by flow cytometry and western blot analysis in several cancer cell lines. The ability of 33B7 conjugated to saporin to inhibit in vitro proliferation of PTFRN positive cell lines was investigated, as well as the 33B7 ADC in vivo effect on tumor growth in athymic mice. All flow cytometry and in vitro internalization assays were analyzed for statistical significance using a Welsh's T-test. Animal studies were analyzed using Two-Way Analysis of Variance (ANOVA) utilizing post-hoc Bonferroni analysis, and/or Mixed Effects analysis. The 33B7 cell surface target was identified as Prostaglandin F2 Receptor Negative Regulator (PTGFRN), a transmembrane protein in the Tetraspanin family. This target was confirmed by showing that PTGFRN-expressing cells bound and internalized 33B7, compared to PTGFRN negative cells. Cells able to bind 33B7 were PTGFRN-positive by Western blot analysis. In vitro treatment PTGFRN-positive cancer cell lines with the 33B7-saporin ADC inhibited their proliferation in a dose-dependent fashion. 33B7 conjugated to saporin was also able to block tumor growth in vivo in mouse xenografts when compared to a control ADC. These findings show that screening antibody libraries for internalizing antibodies in cancer cell lines is a good approach to identify new cancer targets for ADC development. These results suggest PTGFRN is a possible therapeutic target via antibody-based approach for certain cancers.
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Prostaglandin F2 alpha stimulates transforming growth factor alpha expression in adipocyte precursors
Endocrinology, 1995Co-Authors: Nancy M Lepak, Ginette SerreroAbstract:Transforming growth factor-alpha (TGF alpha) and Prostaglandin F2 alpha (PGF2 alpha) are potent inhibitors of adipocyte differentiation. We demonstrate here that TGF alpha messenger RNA (mRNA) is expressed in freshly isolated fat pads and in primary culture of adipocyte precursors cultivated in defined medium before and after differentiation. We show that PGF2 alpha stimulated TGF alpha mRNA expression in a dose-dependent manner. PGF2 alpha also stimulated TGF alpha production in the culture medium of adipocyte precursors in primary culture. PGF2 alpha stimulated TGF alpha mRNA expression in both undifferentiated and differentiated cells. 9 alpha,11 beta-PGF2 alpha, which also inhibited adipose differentiation, stimulated TGF alpha mRNA expression similarly to PGF2 alpha, whereas other PGs had no effect on TGF alpha mRNA expression. The time-course experiment indicates that the stimulation of TGF alpha mRNA expression by PGF2 alpha is observed within 6 h of exposure to PGF2 alpha and is inhibited by treat...
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paracrine regulation of adipose differentiation by arachidonate metabolites Prostaglandin F2 alpha inhibits early and late markers of differentiation in the adipogenic cell line 1246
Endocrinology, 1992Co-Authors: Ginette Serrero, Nancy M Lepak, Stephen P GoodrichAbstract:The effect of arachidonate metabolites on the differentiation of the adipogenic cell line 1246 was investigated. Among the metabolites examined, only Prostaglandin F2 alpha (PGF2 alpha) inhibited differentiation in a dose-dependent fashion with an ED50 of 3 x 10(-9) M. PGF2 alpha inhibited the mRNA expression of lipoprotein lipase, clone 154, and fatty acid-binding protein, which are early markers of differentiation, as well as glycerol-3-phosphate dehydrogenase specific activity and triglyceride accumulation, which are late markers of differentiation. Chronic exposure of 1246 cells to PGF2 alpha before and during differentiation indicated that the cells that have just initiated their differentiation program were the most susceptible to the inhibitory effect of PGF2 alpha. Since 1246 cells produce PGs, we determined whether the PG produced by the cells influenced adipose differentiation. Cyclooxygenase inhibitors added to the culture medium stimulated differentiation of 1246 cells up to 18-fold depending on the type and concentration of inhibitor used. In contrast, lipoxygenase inhibitors had no effect. Treatment of 1246 cells with arachidonic acid resulted in a dose-dependent inhibition of cell differentiation. Oleate or linoleate had no effect. These data indicate that PGF2 alpha inhibits early and late events of adipose differentiation and that the endogenous production of PGs (particularly PGF2 alpha) plays an important role as a negative paracrine or autocrine regulatory pathway of adipose differentiation.
John W Regan - One of the best experts on this subject based on the ideXlab platform.
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Prostaglandin F2 alpha receptors in the human trabecular meshwork.
Investigative Ophthalmology & Visual Science, 1998Co-Authors: Todd L. Anthony, William D. Stamer, Kristen L. Pierce, John W ReganAbstract:PURPOSE: Prostaglandin F2 alpha (PGF2 alpha) and analogs, such as latanoprost, are thought to lower intraocular pressure (IOP), primarily by increasing uveoscleral outflow. However, outflow through the trabecular meshwork may be increased as well. The authors hypothesize that any effect on the trabecular meshwork is mediated by prostanoid FP receptors (receptors for Prostaglandin F2 alpha) in this tissue. METHODS: To test this hypothesis, tissue sections of the human trabecular meshwork and cultures of human trabecular meshwork cells were examined for the presence of FP receptors using immunofluorescence microscopy with affinity-purified antibodies raised against a glutathione-S-transferase (GST)-FPA receptor fusion protein. The presence of the receptor was confirmed by using reverse transcription-polymerase chain reaction (RT-PCR), functional assays of PGF2 alpha-stimulated inositol phosphate hydrolysis, and intracellular calcium measurements. RESULTS: Positive FPA receptor immunolabeling was observed in sections of the human trabecular meshwork and in cultured human trabecular meshwork cells. In both cases, specific labeling could be blocked by preincubation with a GST-FPA receptor fusion protein. Cross-blocking experiments with other receptor fusion proteins did not block specific labeling in cultured trabecular meshwork cells. PGF2 alpha caused a dose-dependent increase in total inositol phosphate accumulation and intracellular calcium release in human trabecular meshwork cells that was consistent with the presence of FP receptors. Using RT-PCR, message-encoding prostanoid FPA receptors were found in total RNA isolated from human trabecular meshwork cells. CONCLUSIONS: Prostanoid FPA receptors exist in human trabecular meshwork cells, as shown by the presence of mRNA, protein, and functional response to PGF2 alpha. This study indicates that functional FP receptors are present in the human trabecular meshwork and that they may be involved in mediating some of the IOP-lowering effects of PGF2 alpha in the eye.
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cloning of a receptor for Prostaglandin F2 alpha from the ovine corpus luteum
Endocrinology, 1995Co-Authors: P E Graves, Kristen L. Pierce, Thomas J Bailey, Bo R Rueda, Daniel W Gil, D F Woodward, Andrea J Yool, Patricia B Hoyer, John W ReganAbstract:A complementary DNA clone encoding a functional receptor for Prostaglandin F2 alpha (PGF2 alpha) has been isolated from an ovine large luteal cell complementary DNA library (prepared from day 10 mid-luteal phase RNA). This receptor, which has been designated FP, consists of 362 amino acids (M(r) = 40,982) and is a member of the family of G protein-coupled receptors. Radioligand binding studies with membranes prepared from transfected COS cells demonstrated specific 17-[3H]phenyl-trinor-PGF2 alpha binding that was displaced by prostanoids in the order of 17-phenyl-trinor-PGF2 alpha > PGF2 alpha > fluprostenol > PGD2 > PGE2 >> 8-epi PGF2 alpha. Xenopus laevis oocytes injected with RNA encoding the ovine FP receptor responded to 17-phenyl-trinor-PGF2 alpha with increased membrane chloride conductance in calcium-free medium. Northern blot analysis with RNA from day 10 corpus luteum showed a major band of approximately 6.1 kilobases. On day 14, when luteolysis usually starts, the abundance of this 6.1-kilobase...
