Modulation of pp60c-src activity and cellular localization during differentiation of human trophoblast cells in culture

1993 ◽  
Vol 105 (3) ◽  
pp. 629-636 ◽  
Author(s):  
C. Rebut-Bonneton ◽  
S. Boutemy-Roulier ◽  
D. Evain-Brion
Keyword(s):  
Tyrosine Kinase ◽  
Cellular Localization ◽  
Kinase Activity ◽  
Cell Aggregation ◽  
Trophoblast Cells ◽  
Tyrosine Kinase Activity ◽  
Human Trophoblast ◽  
Human Trophoblast Cells ◽  
E Cadherin

The morphological and functional differentiation of human trophoblast cells ends with the formation of terminally differentiated multinucleated syncytial trophoblasts. This in vivo differentiation is mimicked in vitro during the primary culture of extravillous cytotrophoblasts: isolated mononuclear cytotrophoblasts aggregate and fuse to form syncytia. This in vitro differentiation is associated with an increase in epidermal growth factor receptor (EGF-R) expression and a transitory increase in E-cadherin expression during cell aggregation. In the present study, we investigated the expression of pp60c-src during morphological differentiation of trophoblast cells. Cultures were terminated at various time intervals and pp60c-src was analysed by immunocytochemistry using a specific antibody. In addition, pp60c-src was investigated by western blot analysis and its tyrosine kinase activity was measured concomitantly. In mononuclear cytotrophoblasts, pp60c-src was localized at cell-matrix contacts and during the aggregation of cytotrophoblasts, pp60c-src was distributed on the cell surface at points of cell-cell contact being colocalized with EGF-R and E-cadherin. The kinase activity of the pp60c-src protein increased significantly at day 2 when cells were completely aggregated and started to fuse, and remained elevated while cells underwent further differentiation. Inhibition of pp60c-src by herbimycin A at 0.25 to 1 microgram/ml during the first day of culture was associated with a decreased expression of tyrosine kinase activity of EGF-R and an increase in E-cadherin expression. These data suggest that pp60c-src is involved in the modulation of trophoblast cell aggregation and fusion leading to syncytial formation.

Effect of a Soluble Factor Secreted From Cultured Human Trophoblast Cells on In Vitro Lymphocyte Reactions

1987 ◽  
Vol 13 (4) ◽  
pp. 121-124 ◽  
Author(s):  
FUMITAKA SAJI ◽  
MASAYASU KOYAMA ◽  
TAKASHI KAMEDA ◽  
TAKAO NEGORO ◽  
KARO NAKAMURO ◽  
...  
Keyword(s):  
Soluble Factor ◽  
Trophoblast Cells ◽  
Human Trophoblast ◽  
Human Trophoblast Cells

Reduction of tyrosine kinase activity and protein tyrosine dephosphorylation by anoxic stimulation in vitro

Neuroscience ◽  
1997 ◽  
Vol 82 (1) ◽  
pp. 161-170 ◽  
Author(s):  
J.L Braunton ◽  
V Wong ◽  
W Wang ◽  
M.W Salter ◽  
J Roder ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Tyrosine Kinase Activity ◽  
Protein Tyrosine

scholarly journals Kidney-Replenishing Herb Induces SOCS-3 Expression via ERK/MAPK Pathway and Improves Growth of the First-Trimester Human Trophoblast Cells

2017 ◽  
Vol 2017 ◽  
pp. 1-12
Author(s):  
Chang-ying Xing ◽  
De-xiang Zhang ◽  
Sui-qi Gui ◽  
Min-fang Tao
Keyword(s):  
Mapk Pathway ◽  
Recurrent Miscarriage ◽  
First Trimester ◽  
Mek Inhibitor ◽  
Biological Functions ◽  
Trophoblast Cells ◽  
Human Trophoblast ◽  
Mitogen Activated Protein ◽  
Human Trophoblast Cells

Kidney-replenishing herb is a traditional medicine formula in China which has been widely used for clinical treatment of recurrent miscarriage. Our previous study showed that Kidney-replenishing herb could promote proliferation and inhibit apoptosis of the human first-trimester trophoblasts. In the present study, we further explored the potential mechanism and signal pathway of Kidney-replenishing herb on human trophoblast cells. Our research showed that Kidney-replenishing herb stimulated proliferation and reduced apoptosis of human trophoblast cells in vitro, and this appeared to be positive correlation with SOCS-3 transcription, suggesting that Kidney-replenishing herb regulated biological functions of human trophoblast cells by inducing SCOS-3 expression. Furthermore, the Kidney-replenishing herb treatment stimulated the phosphorylation of ERK1/2, and blocking the signaling pathway by mitogen-activated protein MAPK (MEK) inhibitor, U0126, inhibited Kidney-replenishing herb-induced SOCS-3 transcription, depressed proliferation, and promoted apoptosis of human trophoblasts. Kidney-replenishing herbs still induced ERK1/2 phosphorylation after SOCS-3 siRNA silence. Overexpression of SOCS-3 stimulated the proliferation of trophoblast. These findings suggest that SOCS-3 expression is induced by Kidney-replenishing herbs via activation of MAPK pathways, and this may possibly be involved in promoting human trophoblast cells growth which is contributed to embryo development.

scholarly journals Activation of the c-abl oncogene by viral transduction or chromosomal translocation generates altered c-abl proteins with similar in vitro kinase properties.

1985 ◽  
Vol 5 (1) ◽  
pp. 204-213 ◽  
Author(s):  
R L Davis ◽  
J B Konopka ◽  
O N Witte
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Leukemia Virus ◽  
Leukemia Cell ◽  
Chromosomal Translocation ◽  
Leukemia Cell Line ◽  
Tyrosine Kinase Activity ◽  
Serine Kinase ◽  
Abelson Murine Leukemia Virus

The v-abl protein of Abelson murine leukemia virus is a tyrosine-specific kinase. Its normal cellular homolog, murine c-abl, does not possess detectable tyrosine kinase activity in vitro. Previously, we have detected tyrosine kinase activity in vitro for an altered c-abl gene product (c-abl P210) in the K562 human chronic myelogenous leukemia cell line. The expression of this variant c-abl gene product correlates with chromosomal translocation and amplification of the c-abl gene in K562 cells. Like v-abl, c-abl P210 is a fusion protein containing non-abl sequences near the amino terminus of c-abl. We compared the in vitro tyrosine kinase activity of c-abl P210 with that of wild-type murine v-abl. The remarkable similarities of these two proteins with respect to cis-acting autophosphorylation, trans-acting phosphorylation of exogenous substrates, and kinase inhibition, using site-directed abl-specific antisera, suggested that c-abl P210 could function similarly to v-abl in vivo. In addition, c-abl P210 possessed an associated serine kinase activity in immunoprecipitates. The serine kinase activity was not inhibited by site-directed, abl-specific antisera that inhibit the tyrosine kinase activity, suggesting that the serine kinase activity is not an intrinsic property of c-abl P210. Thus, the activation of the c-abl gene in a human leukemia cell line may have functional consequences analogous to activation of the c-abl gene in Abelson murine leukemia virus.

Differentiation of human trophoblast cells in vitro stimulated by extracellular matrix

Placenta ◽  
1993 ◽  
Vol 14 ◽  
pp. 181-200
Author(s):  
Hans-Peter Hohn ◽  
Larry R. Boots ◽  
Hans-Werner Denker ◽  
Magnus Höök
Keyword(s):  
Extracellular Matrix ◽  
Trophoblast Cells ◽  
Human Trophoblast ◽  
Human Trophoblast Cells

scholarly journals Mammary tumors expressing the neu proto-oncogene possess elevated c-Src tyrosine kinase activity.

1994 ◽  
Vol 14 (1) ◽  
pp. 735-743 ◽  
Author(s):  
S K Muthuswamy ◽  
P M Siegel ◽  
D L Dankort ◽  
M A Webster ◽  
W J Muller
Keyword(s):  
Signal Transduction ◽  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Specific Activity ◽  
Fusion Gene ◽  
Mammary Tumorigenesis ◽  
Mammary Tumors ◽  
Tyrosine Kinase Activity ◽  
Src Tyrosine Kinase

Amplification and overexpression of the neu (c-erbB2) proto-oncogene has been implicated in the pathogenesis of 20 to 30% of human breast cancers. Although the activation of Neu receptor tyrosine kinase appears to be a pivotal step during mammary tumorigenesis, the mechanism by which Neu signals cell proliferation is unclear. Molecules bearing a domain shared by the c-Src proto-oncogene (Src homology 2) are thought to be involved in signal transduction from activated receptor tyrosine kinases such as Neu. To test whether c-Src was implicated in Neu-mediated signal transduction, we measured the activity of the c-Src tyrosine kinase in tissue extracts from either mammary tumors or adjacent mammary epithelium derived from transgenic mice expressing a mouse mammary tumor virus promoter/enhancer/unactivated neu fusion gene. The Neu-induced mammary tumors possessed six- to eightfold-higher c-Src kinase activity than the adjacent epithelium. The increase in c-Src tyrosine kinase activity was not due to an increase in the levels of c-Src but rather was a result of the elevation of its specific activity. Moreover, activation of c-Src was correlated with its ability to complex tyrosine-phosphorylated Neu both in vitro and in vivo. Together, these observations suggest that activation of the c-Src tyrosine kinase during mammary tumorigenesis may occur through a direct interaction with activated Neu.

Inhibition by two lavendustins of the tyrosine kinase activity of pp60F527 in vitro and in intact cells

1994 ◽  
Vol 269 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Wenceslas K. Agbotounou ◽  
Kazuo Umezawa ◽  
Alain Jacquemin-Sablon ◽  
Josiane Pierre
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Tyrosine Kinase Activity ◽  
Intact Cells

Leukemic Stem Cells of Chronic Phase CML Patients Possess Uniquely Elevated BCR-ABL Kinase Activity and Acquire Spontaneous BCR-ABL Kinase Domain Mutations at a High Frequency.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 438-438 ◽  
Author(s):  
Xiaoyan Jiang ◽  
Kyi Min Saw ◽  
Allen Eaves ◽  
Connie Eaves
Keyword(s):  
Stem Cells ◽  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Point Mutations ◽  
Chronic Phase ◽  
Kinase Domain ◽  
Tyrosine Kinase Activity ◽  
Abl Kinase ◽  
Kinase Domain Mutations

Abstract Growing evidence indicates that the therapeutic potential of imatinib mesylate (IM) for the treatment of CML may be limited initially by a relative innate resistance of the leukemic stem cells and eventually by an accumulation of cells with BCR-ABL tyrosine kinase domain mutations. We now show that the amount and tyrosine kinase activity of p210-BCR-ABL in the most primitive and relatively IM-unresponsive lin−CD34+CD38− CML cells is 3 to 10-fold higher than in the majority of the lin−CD34+CD38+ CML progenitors (n=3). These results confirm previous BCR-ABL transcript data and identify elevated p210-BCR-ABL expression to be a likely important factor in the characteristic IM-insensitivity of very primitive CML cells. To determine whether in vivo, CML stem cells also accumulate gene mutations affecting the BCR-ABL kinase domain, cDNAs were prepared from RNA extracts of purified lin−CD34+CD38− cells isolated from 3 chronic phase patients that had not received IM therapy. Bidirectional sequencing of individually cloned cDNAs from these samples revealed BCR-ABL kinase domain mutations in 2 of the 3 patients at frequencies of 10% (1/10), 20% (2*/10,*identical mutations). Incubation of these lin−CD34+CD38− cells in vitro for 2–3 wk ± a high concentration of IM (up to 10 μM, which was sufficient to reduce the tyrosine kinase activity in the input cells by 70±12% and in their 2 wk progeny by 10±5%) selected a subpopulation of more differentiated and completely IM-resistant cells. This was shown in Western blots by the inability of 10 μM IM to reduce either their p210-BCR-ABL tyrosine kinase activity or CrkL phosphorylation and in methylcellulose assays ±5 μM IM. As predicted, IM-selected cells showed a higher frequency of kinase domain mutations (13–20% vs 0–20% of cDNA clones analyzed from 3 wk cells cultured ±IM). Analysis of individual colonies produced from CFCs in the cultured cells showed all (21/21) colonies from IM-selected cells had mutations vs 50% (5/10) in those cultured without IM. The total frequency of mutant cDNAs detected was also increased in the IM-resistant cells (35–55% vs 10–25% mutant cDNAs in selected vs control cells). Interestingly, in most cases, both wild-type and mutant cDNAs were identified in the same colony, indicating de novo generation of mutations in vitro. Overall, >50 different mutations were identified. These included 10 point mutations previously associated with clinical IM resistance (including G250 and T315), another 13 point mutations previously identified in a comprehensive mutational screen, and >20 previously undescribed mutations. Several of the latter affect the critical region of the P loop, the c-helix and the activation loop and would be predicted to confer significant IM resistance. To investigate the possibility that the observed genomic instability of very primitive CML cells might be related to their elevated innate p210-BCR-ABL activity, BCR-ABL transcript levels in individual IM-selected, fully resistant and control (similarly treated but no IM exposure) colonies were compared. This showed that BCR-ABL transcripts were ~20-fold higher (P<0.05) in the resistant colonies (30 assessed from 3 patients). These findings suggest that the increased BCR-ABL expression and activity that uniquely characterizes the most primitive CML cells may contribute not only to their innate insensitivity to IM but also to a deregulation of genomic stability leading to the emergence of IM-resistant mutants and other subclones associated with disease progression.

scholarly journals Moderate Hypoxia Down-Regulates Interleukin-6 Secretion and TLR4 Expression in Human Sw.71 Placental Cells

2015 ◽  
Vol 36 (6) ◽  
pp. 2149-2160 ◽  
Author(s):  
Koumei Shirasuna ◽  
Narumi Shimamura ◽  
Kotomi Seno ◽  
Ayaka Ohtsu ◽  
Shogo Shiratsuki ◽  
...  
Keyword(s):  
Interleukin 6 ◽  
Ros Production ◽  
Tlr4 Expression ◽  
Trophoblast Cells ◽  
Human Trophoblast ◽  
Moderate Hypoxia ◽  
Hypoxic Conditions ◽  
Markers Of Inflammation ◽  
Human Trophoblast Cells

Background/Aims: The placenta is a vital organ for pregnancy. Many in vitro placental experiments are conducted under 21% O2; however, O2 tension could influence cellular functions, including cytokine secretion. We investigated the effects of oxygen tension between moderate hypoxia (5% O2) and normoxia (21% O2) by testing the hypothesis that moderate hypoxia regulates cellular phenotypes differently from normoxia in human trophoblast cells. Methods and Results: Sw.71 trophoblast cells were incubated under normoxic or moderately hypoxic conditions. Cells were also treated with lipopolysaccharide (LPS) as a Toll-like receptor 4 (TLR4) ligand inducing inflammation. Interleukin-6 (IL-6) as an inflammatory cytokine was determined, and TLR4, hypoxia-induced factor-1α (HIF1α), and reactive oxygen species (ROS) production were detected. Moderate hypoxia increased HIF1α expression and cell proliferation and acted by two different mechanisms to decrease IL-6 secretion compared with normoxia: it limits the TLR4 expression and ROS production. Treatment with cobalt chloride as an HIF1 activator inhibited IL-6 secretion and TLR4 expression; this effect was reversed on treatment with PX-12 as an HIF1 suppressor. Conclusion: IL-6 secretion, TLR4 expression, and ROS production, classical markers of inflammation, are down-regulated by moderate hypoxia, and HIF1α and ROS have a potential to regulate these responses in human trophoblast cells.

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