Stem cell factor affects fate determination of human gonocytes in vitro

The stem cell factor (SCF), binding its tyrosine kinase receptor c-Kit, has been shown to play essential roles in the proliferation, differentiation, and survival of germline cells. However, few reports are available about the effect of SCF on the development of human gonocytes within the fetal testis. The objective of this study was to investigate whether SCF affects the biological behaviors of human gonocytes before or after they enter the mitotic arrest stage. Employing an organ culture system, we observed that addition of exogenous SCF could influence the morphology of human gonocytesin vitro. Moreover, SCF was able to trigger the colony formation of round gonocytes, which were characterized positive for alkaline phosphatase activity, Oct-4, SSEA-4, and c-Kit as well. We found that SCF exerted actions in a dose- and age-dependent manner, although the stimulatory effect lasted no more than 14 days. We also showed that SCF played a role in suppressing the apoptosis of human gonocytes. Blocking of SCF signaling with either phosphatidylinositol 3-kinase or mitogen-activated protein kinase inhibitor resulted in similar apoptotic features as well as the SCF-withdrawal cultures. Taken together, we report that SCF acts as a potent regulator in the fate determination of human gonocytes. Our studies should form the basis forin vitrostudies and facilitate investigation of the molecular mechanisms underlying this unique stage.

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P–314 Serum Stem Cell Factor as a predictor of top quality blasotcysts formation in women with endometriosis

Human Reproduction ◽

10.1093/humrep/deab130.313 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

J Liss ◽

M Kuczynska ◽

A Knight ◽

K Lukaszuk

Keyword(s):

Stem Cell ◽

Ovarian Stimulation ◽

Stem Cell Factor ◽

Enzyme Linked Immunosorbent Assay ◽

Tyrosine Kinase Receptor ◽

Target Cells ◽

Serum Samples ◽

The Mean ◽

Ovary Reserve

Abstract Study question To evaluate the correlation between the serum level of stem cell factor (s-SCF) during the stimulation and results of embryo culture. Summary answer The serum SCF concentration at the stimulation stage may be a potential predictor of IVF outcome in endometriosis patients. What is known already Stem cell factor (SCF) is a pleiotropic cytokine that affects the target cells via the c-kit receptor, a tyrosine kinase receptor. Recent evidence indicates that SCF and c-kit may play a role in regulation and growth of ovarian follicular function. It is unclear whether endometriosis primarily affects in vitro fertilization outcomes via oocyte quality. SCF is produced during the human follicular phase, immediately before the ovulatory phase, and may play an important role in folliculogenesis and in the mechanism of ovulation. It may reflect a successful stimulation with ample follicle maturation. Study design, size, duration This was a prospective case-control study and consisted four group of patients: 10 with endometriosis, 24 PCOs, 20 with normal (AMH 1.2–4.0 ng/ml) and 11 with lower (AMH<1.2 ng/ml) ovary reserve who were undergoing IVF treatment with the assessment of serum SCF concentration between August 2019 and March 2020 at INVICTA Fertility Centre, Poland. The age of the patients ranged from 22 to 42 years (median 34 years). Participants/materials, setting, methods s-SCF was measured in duplicate by enzyme-linked immunosorbent assay (ELISA) kit in 195 serum samples collected during ovarian stimulation on days 1 and 8 and on the day of oocyte retrieval. We analysed correlation between s-SCF level and formation of top quality (TQ) blastocysts on day 5 formation in the study groups. Main results and the role of chance We have compared mean level of s-SCF within each group dividing the patients into two subgroups – those with at least one TQ blastocyst (TQ) on day 5 vs. those with no TQ blastocysts (no-TQ). There were no significant differences in mean s-SCF level on day 1 of stimulation between no-TQ and TQ patients in PCOs, normal and lower ovary reserve groups (41.1 pg/ml vs. 40.9 pg/ml; 34.8 pg/ml vs. 38.9 pg/ml and 32.3pg/ml vs. 28.7 pg/ml respectively). The mean level of s-SCF in endometriosis patients was higher in case of no-TQ compared to the TQ subgroup and were 41.1 pg/ml and 29.1 pg/ml respectively. Also no significant differences were also observed in the mean level of s-SCF in the no-TQ and TQ subgroups on the 8 day of stimulation and pick-up in PCOs, normal and lower ovary reserve patients. However, again in the case of endometriosis patients, the mean level of s-SCF was significantly lower on the 8 day of stimulation (28.1 pg/ml vs. 49.1 pg/ml; p < 0.05) and pick-up day (33.4 pg/ml vs. 50.4 pg/ml; p < 0.005) in samples from patients who had at least one TQ blastocysts on day 5 of culture. Limitations, reasons for caution More data are required to confirm the corelation of s-SCF level and presence of top quality blastocysts in patients with endometriosis. Wider implications of the findings: Our study suggests that the level of serum SCF during ovarian stimulation in patients with endometriosis of less 30 pg/ml may potentially be a predictor for the chance of obtaining at least one top quality blastocyst on day 5 and thus a chance to successful treatment. Trial registration number Not applicable

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Stem cell factor and interleukin-7 synergize to enhance early myelopoiesis in vitro

Blood ◽

10.1182/blood.v84.5.1450.1450 ◽

1994 ◽

Vol 84 (5) ◽

pp. 1450-1456 ◽

Cited By ~ 11

Author(s):

C Fahlman ◽

HK Blomhoff ◽

OP Veiby ◽

IK McNiece ◽

SE Jacobsen

Keyword(s):

Stem Cell ◽

B Cells ◽

Stem Cell Factor ◽

Critical Factor ◽

Dependent Manner ◽

Murine Bone Marrow ◽

Proliferative Effect ◽

Interleukin 7 ◽

Potent Growth

Abstract Interleukin-7 (IL-7) has been shown to be a critical factor in murine lymphoid development. It stimulates pre-B cells to divide in the absence of stroma cells and it is an important growth regulator of immature and mature T cells. IL-7 has been shown to synergize with stem cell factor (SCF) to provide a potent growth stimulus for pre-B cells. However, the combined effects of IL-7 and SCF on murine primitive hematopoietic cells in vitro have not been established. In the present study, the effects of recombinant rat (rr) SCF and recombinant human (rh) IL-7 on primitive murine bone marrow progenitors (Lin-Sca1+) were investigated in single-cell cloning experiments. rhIL-7 alone had no proliferative effect on Lin-Sca1+ cells, but in a dose-dependent manner directly enhanced rrSCF-induced colony formation, with an average increase in colony numbers of 2.7-fold. Interestingly, the cells formed in response to SCF and IL-7 were predominantly mature granulocytes. Thus, SCF and IL-7 synergize to stimulate early myelopoiesis in vitro.

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Stem cell factor and interleukin-7 synergize to enhance early myelopoiesis in vitro

Blood ◽

10.1182/blood.v84.5.1450.bloodjournal8451450 ◽

1994 ◽

Vol 84 (5) ◽

pp. 1450-1456 ◽

Cited By ~ 1

Author(s):

C Fahlman ◽

HK Blomhoff ◽

OP Veiby ◽

IK McNiece ◽

SE Jacobsen

Keyword(s):

Stem Cell ◽

B Cells ◽

Stem Cell Factor ◽

Critical Factor ◽

Dependent Manner ◽

Murine Bone Marrow ◽

Proliferative Effect ◽

Interleukin 7 ◽

Potent Growth

Interleukin-7 (IL-7) has been shown to be a critical factor in murine lymphoid development. It stimulates pre-B cells to divide in the absence of stroma cells and it is an important growth regulator of immature and mature T cells. IL-7 has been shown to synergize with stem cell factor (SCF) to provide a potent growth stimulus for pre-B cells. However, the combined effects of IL-7 and SCF on murine primitive hematopoietic cells in vitro have not been established. In the present study, the effects of recombinant rat (rr) SCF and recombinant human (rh) IL-7 on primitive murine bone marrow progenitors (Lin-Sca1+) were investigated in single-cell cloning experiments. rhIL-7 alone had no proliferative effect on Lin-Sca1+ cells, but in a dose-dependent manner directly enhanced rrSCF-induced colony formation, with an average increase in colony numbers of 2.7-fold. Interestingly, the cells formed in response to SCF and IL-7 were predominantly mature granulocytes. Thus, SCF and IL-7 synergize to stimulate early myelopoiesis in vitro.

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Inhibition of MELK Protooncogene as an Innovative Treatment for Intrahepatic Cholangiocarcinoma

Medicina ◽

10.3390/medicina56010001 ◽

2019 ◽

Vol 56 (1) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Antonio Cigliano ◽

Maria Giulia Pilo ◽

Marta Mela ◽

Silvia Ribback ◽

Frank Dombrowski ◽

...

Keyword(s):

Cell Lines ◽

Intrahepatic Cholangiocarcinoma ◽

Leucine Zipper ◽

Molecular Mechanisms ◽

Kinase Inhibitor ◽

Prognostic Indicator ◽

Dependent Manner ◽

Downstream Target ◽

Forkhead Box M1

Background and Objectives: Intrahepatic cholangiocarcinoma (iCCA) is a pernicious tumor characterized by a dismal outcome and scarce therapeutic options. To substantially improve the prognosis of iCCA patients, a better understanding of the molecular mechanisms responsible for development and progression of this disease is imperative. In the present study, we aimed at elucidating the role of the maternal embryonic leucine zipper kinase (MELK) protooncogene in iCCA. Materials and Methods: We analyzed the expression of MELK and two putative targets, Forkhead Box M1 (FOXM1) and Enhancer of Zeste Homolog 2 (EZH2), in a collection of human iCCA by real-time RT-PCR and immunohistochemistry (IHC). The effects on iCCA growth of both the multi-kinase inhibitor OTSSP167 and specific small-interfering RNA (siRNA) against MELK were investigated in iCCA cell lines. Results: Expression of MELK was significantly higher in tumors than in corresponding non-neoplastic liver counterparts, with highest levels of MELK being associated with patients’ shorter survival length. In vitro, OTSSP167 suppressed the growth of iCCA cell lines in a dose-dependent manner by reducing proliferation and inducing apoptosis. These effects were amplified when OTSSP167 administration was coupled to the DNA-damaging agent doxorubicin. Similar results, but less remarkable, were obtained when MELK was silenced by specific siRNA in the same cells. At the molecular level, siRNA against MELK triggered downregulation of MELK and its targets. Finally, we found that MELK is a downstream target of the E2F1 transcription factor. Conclusion: Our results indicate that MELK is ubiquitously overexpressed in iCCA, where it may represent a prognostic indicator and a therapeutic target. In particular, the combination of OTSSP167 (or other, more specific MELK inhibitors) with DNA-damaging agents might be a potentially effective therapy for human iCCA.

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Stem cell factor and interleukin-2/15 combine to enhance MAPK-mediated proliferation of human natural killer cells

Blood ◽

10.1182/blood-2008-05-159285 ◽

2009 ◽

Vol 113 (12) ◽

pp. 2706-2714 ◽

Cited By ~ 24

Author(s):

Don M. Benson ◽

Jianhua Yu ◽

Brian Becknell ◽

Min Wei ◽

Aharon G. Freud ◽

...

Keyword(s):

Stem Cell ◽

Nk Cells ◽

Natural Killer ◽

Stem Cell Factor ◽

Molecular Mechanisms ◽

Cellular Proliferation ◽

Nk Cell ◽

Interleukin 2 ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase

Abstract Stem cell factor (SCF) promotes synergistic cellular proliferation in combination with several growth factors, and appears important for normal natural killer (NK)–cell development. CD34+ hematopoietic precursor cells (HPCs) require interleukin-15 (IL-15) for differentiation into human NK cells, and this effect can be mimicked by IL-2. Culture of CD34+ HPCs or some primary human NK cells in IL-2/15 and SCF results in enhanced growth compared with either cytokine alone. The molecular mechanisms responsible for this are unknown and were investigated in the present work. Activation of NK cells by IL-2/15 increases expression of c-kit whose kinase activity is required for synergy with IL-2/15 signaling. Mitogen-activated protein kinase (MAPK) signaling intermediaries that are activated both by SCF and IL-2/15 are enhanced in combination to facilitate earlier cell-cycle entry. The effect results at least in part via enhanced MAPK-mediated modulation of p27 and CDK4. Collectively the data reveal a novel mechanism by which SCF enhances cellular proliferation in combination with IL-2/15 in primary human NK cells.

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Thrombopoietin (c-mpl ligand) acts synergistically with erythropoietin, stem cell factor, and interleukin-11 to enhance murine megakaryocyte colony growth and increases megakaryocyte ploidy in vitro

Blood ◽

10.1182/blood.v85.7.1719.bloodjournal8571719 ◽

1995 ◽

Vol 85 (7) ◽

pp. 1719-1726 ◽

Cited By ~ 293

Author(s):

VC Broudy ◽

NL Lin ◽

K Kaushansky

Keyword(s):

Stem Cell ◽

Growth Factors ◽

Stem Cell Factor ◽

Horse Serum ◽

Colony Growth ◽

Dependent Manner ◽

Synergistic Enhancement ◽

Marrow Cells

Thrombopoietin (Tpo), the ligand for the c-mpl receptor, is a major regulator of platelet production in vivo. Treatment of mice with purified recombinant Tpo increases platelet count fourfold and expands colony-forming unit-megakaryocyte (CFU-Meg) numbers. Other cytokines including interleukin-3 (IL-3), IL-6, IL-11, erythropoietin (Epo), and stem cell factor (SCF) can stimulate megakaryopoiesis. Therefore, we examined the effects of recombinant murine Tpo in combination with these cytokines on megakaryopoiesis in vitro. Murine marrow cells were cultured in agar in Iscove's modified Dulbecco's medium (IMDM) supplemented with 10% horse serum and beta-mercaptoethanol in the presence of recombinant growth factors, and CFU-Meg colonies were counted on day 5. Megakaryocyte ploidy was analyzed using murine marrow cells cultured for 5 days in IMDM supplemented with 1% nutridoma-SP and recombinant growth factors. Megakaryocytes were identified by labeling with the 4A5 antibody and ploidy was analyzed by flow cytometry. Tpo supported the growth of CFU-Meg in a dose-dependent manner. Although the addition of SCF (50 ng/mL), Epo (2 U/mL), or IL-11 (50 ng/mL) alone exerted only a modest effect on CFU-Meg growth, the combination of SCF plus Tpo, Epo plus Tpo, or IL-11 plus Tpo resulted in a synergistic enhancement of the number of CFU-Meg colonies. IL-3 alone supported CFU- Meg colony growth, and the effects of IL-3 plus Tpo or IL-6 plus Tpo on colony growth appeared to be approximately additive. Fifty percent of megakaryocytes generated in cultures containing IL-3 or Epo displayed < or = 16 N ploidy. In contrast, cultures containing Tpo uniquely generated large numbers (30% to 35% of the total) of megakaryocytes with > or = 64N ploidy. These results show that Tpo stimulates both proliferation of committed megakaryocytic progenitor cells and maturation of megakaryocytes, and that two multipotent cytokines, SCF and IL-11, as well as a late-acting erythroid cytokine, Epo, can synergize with Tpo to stimulate proliferation of CFU-Meg.

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P2X7 receptors activate protein kinase D and p42/p44 mitogen-activated protein kinase (MAPK) downstream of protein kinase C

Biochemical Journal ◽

10.1042/bj20020358 ◽

2002 ◽

Vol 366 (3) ◽

pp. 745-755 ◽

Cited By ~ 59

Author(s):

Michelle D. BRADFORD ◽

Stephen P. SOLTOFF

Keyword(s):

Protein Kinase ◽

Tyrosine Kinases ◽

P2x7 Receptor ◽

Kinase Inhibitor ◽

Mitogen Activated Protein Kinase ◽

Protein Kinase D ◽

Dependent Manner ◽

P2x7 Receptors ◽

High Concentrations

Protein kinase D (PKD), also called protein kinase Cμ (PKCμ), is a serine/threonine kinase that has unique enzymic and structural properties distinct from members of the PKC family of proteins. In freshly isolated rat parotid acinar salivary cells, extracellular ATP rapidly increased the activity and phosphorylation of PKD. The stimulation by ATP required high concentrations, was mimicked by the P2X7 receptor ligand BzATP [2′- and 3′-O-(4-benzoylbenzoyl)ATP], and was blocked by Mg2+ and 4,4′-di-isothiocyano-2,2′-stilbene disulphonate (DIDS), suggesting that activation of PKD was mediated by P2X7 receptors, which are ligand-gated non-selective cation channels. Phorbol ester (PMA) and the activation of muscarinic and substance P receptors also increased PKD activity. PKC inhibitors blocked ligand-dependent PKD activation and phosphorylation, determined by in vitro phosphorylation studies and by phospho-specific antibodies to two activation loop sites (Ser744 and Ser748) and an autophosphorylation site (Ser916). ATP and BzATP also increased the tyrosine phosphorylation and activity of PKCΔ, and these stimuli also increased extracellular signal-regulated protein kinase (ERK) 1/2 activity in a PKC-dependent manner. PKD activation was not promoted by pervanadate (an inhibitor of tyrosine phosphatases) and was not blocked by PP1 (an inhibitor of Src family kinases) or genistein (a tyrosine kinase inhibitor), suggesting that tyrosine kinases and phosphatases did not play a major role in PKD activation. P2X7 receptor-mediated signalling events were not dependent on Ca2+ entry. These studies indicate that PKC is involved in cellular signalling initiated by P2X7 receptors as well as by G-protein-coupled receptors, and demonstrate that PKD and ERK1/2 are activated in similar PKC-dependent signalling pathways initiated by these diverse receptor types.

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JAK2 Activates TFII-I and Regulates Its Interaction with Extracellular Signal-Regulated Kinase

Molecular and Cellular Biology ◽

10.1128/mcb.21.10.3387-3397.2000 ◽

2001 ◽

Vol 21 (10) ◽

pp. 3387-3397 ◽

Cited By ~ 21

Author(s):

Dae-Won Kim ◽

Brent H. Cochran

Keyword(s):

Transcription Factor ◽

Tyrosine Kinase ◽

Tyrosine Phosphorylation ◽

Kinase Inhibitor ◽

Dominant Negative ◽

Mitogen Activated Protein Kinase ◽

Dependent Manner ◽

Serum Stimulation

ABSTRACT TFII-I is a transcription factor that shuttles between the cytoplasm and nucleus and is regulated by serine and tyrosine phosphorylation. Tyrosine phosphorylation of TFII-I can be regulated in a signal-dependent manner in various cell types. In B lymphocytes, Bruton's tyrosine kinase has been identified as a TFII-I tyrosine kinase. Here we report that JAK2 can phosphorylate and regulate TFII-I in nonlymphoid cells. The activity of TFII-I on the c-fospromoter in response to serum can be abolished by dominant negative JAK2 or the specific JAK2 kinase inhibitor AG490. Consistent with this, we have also found that JAK2 is activated by serum stimulation of fibroblasts. Tyrosine 248 of TFII-I is phosphorylated in vivo upon serum stimulation or JAK2 overexpression, and mutation of tyrosine 248 to phenylalanine inhibits the ability of JAK2 to phosphorylate TFII-I in vitro. Tyrosine 248 of TFII-I is required for its interaction with and phosphorylation by ERK and its in vivo activity on the c-fos promoter. These results indicate that the interaction between TFII-I and ERK, which is essential for its activity, can be regulated by JAK2 through phosphorylation of TFII-I at tyrosine 248. Thus, like the STAT factors, TFII-I is a direct substrate of JAK2 and a signal-dependent transcription factor that integrates signals from both tyrosine kinase and mitogen-activated protein kinase pathways to regulate transcription.

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VDAC1 Mediated Anticancer Activity of Gallic Acid in Human Lung Adenocarcinoma A549 Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520617666170912115441 ◽

2018 ◽

Vol 18 (2) ◽

pp. 255-262 ◽

Cited By ~ 5

Author(s):

Aikebaier Maimaiti ◽

Amier Aili ◽

Hureshitanmu Kuerban ◽

Xuejun Li

Keyword(s):

Western Blot ◽

Cell Viability ◽

Gallic Acid ◽

Molecular Mechanisms ◽

A549 Cells ◽

Dependent Manner ◽

Lung Carcinoma Cells ◽

Induced Apoptosis ◽

The Impact

Aims: Gallic acid (GA) is generally distributed in a variety of plants and foods, and possesses cell growth-inhibiting activities in cancer cell lines. In the present study, the impact of GA on cell viability, apoptosis induction and possible molecular mechanisms in cultured A549 lung carcinoma cells was investigated. Methods: In vitro experiments showed that treating A549 cells with various concentrations of GA inhibited cell viability and induced apoptosis in a dose-dependent manner. In order to understand the mechanism by which GA inhibits cell viability, comparative proteomic analysis was applied. The changed proteins were identified by Western blot and siRNA methods. Results: Two-dimensional electrophoresis revealed changes that occurred to the cells when treated with or without GA. Four up-regulated protein spots were clearly identified as malate dehydrogenase (MDH), voltagedependent, anion-selective channel protein 1(VDAC1), calreticulin (CRT) and brain acid soluble protein 1(BASP1). VDAC1 in A549 cells was reconfirmed by western blot. Transfection with VDAC1 siRNA significantly increased cell viability after the treatment of GA. Further investigation showed that GA down regulated PI3K/Akt signaling pathways. These data strongly suggest that up-regulation of VDAC1 by GA may play an important role in GA-induced, inhibitory effects on A549 cell viability.

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The TGFβ Family in Human Placental Development at the Fetal-Maternal Interface

Biomolecules ◽

10.3390/biom10030453 ◽

2020 ◽

Vol 10 (3) ◽

pp. 453

Author(s):

Susana M. Chuva de Sousa Lopes ◽

Marta S. Alexdottir ◽

Gudrun Valdimarsdottir

Keyword(s):

Stem Cell ◽

Transforming Growth Factor Beta ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Cell Model ◽

Embryonic Stem ◽

Model Systems ◽

Special Focus ◽

Placental Development

Emerging data suggest that a trophoblast stem cell (TSC) population exists in the early human placenta. However, in vitro stem cell culture models are still in development and it remains under debate how well they reflect primary trophoblast (TB) cells. The absence of robust protocols to generate TSCs from humans has resulted in limited knowledge of the molecular mechanisms that regulate human placental development and TB lineage specification when compared to other human embryonic stem cells (hESCs). As placentation in mouse and human differ considerably, it is only with the development of human-based disease models using TSCs that we will be able to understand the various diseases caused by abnormal placentation in humans, such as preeclampsia. In this review, we summarize the knowledge on normal human placental development, the placental disease preeclampsia, and current stem cell model systems used to mimic TB differentiation. A special focus is given to the transforming growth factor-beta (TGFβ) family as it has been shown that the TGFβ family has an important role in human placental development and disease.

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