Differing roles of protein kinase C on the antiproliferative effects of tumor necrosis factor alpha and beta on LoVo cells

In this study we examined whether the antiproliferative effects of tumor necrosis factor (TNF)-alpha and beta were associated with the activation of protein kinase C (PKC), using the LoVo human colon cancer cell line which is resistant to both TNFs. In combination with 12-O-tetradecanoylphorbol-13-acetate (TPA), a potent activator of PKC, TNF-alpha caused marked growth inhibition of LoVo cells, but TNF-beta had little antiproliferative effect. There was no difference in the effect when TPA was added 1 h before or 4 h after TNF-alpha administration. A PKC inhibitor, H-7, not only decreased the sensitivity of LoVo cells to TNF-alpha but also caused a slight promotion of cell proliferation and dose-dependently blocked the growth inhibition induced by TNF-alpha and TPA. These results suggested a possible regulatory function of PKC within the TNF-alpha-mediated intracellular signalling pathway. PKC may act at a later stage in the transduction pathway.     

Interferon-α is a Potent Inhibitor of Basic Fibroblast Growth Factor-Stimulated Cell Proliferation in Human Uterine Cells

PROBLEM: Abnormal uterine bleeding is a significant health problem for many women and is the number-one reason for performing hysterectomy in the United States. Leiomyomas (uterine fibroids) are benign neoplams that are a frequent cause of abnormal uterine bleeding. The goal of this study was to assess the effects of the anti-angiogenic cytokine, interferon (INF)-α, on the proliferation of both leiomyoma and normal uterine cells. METHOD OF STUDY: Primary cultures of leiomyoma, myometrial, and endometrial stromal cells were established for in vitro study. The effects of INF-α (10, 100, and 1000 U/ml) were tested on serum-stimulated and basic fibroblast growth factor-stimulated cell proliferation using the [³H]thymidine incorporation assay. RESULTS: INF-α was a potent inhibitor of cell proliferation for all three cell types, with endometrial stromal cells showing the greatest sensitivity. The antiproliferative effect did not appear to result from toxic effects on the cells. CONCLUSION: INFs may prove to be useful therapeutic agents for the treatment of leiomyoma-related abnormal uterine bleeding.     

Cyclin-dependent kinase inhibitor p27Kip1 controls growth and cell cycle progression in human uterine leiomyoma

The molecular mechanism of the cell-cycle machinery in uterine leiomyoma has not yet been fully elucidated. Among the various types of cell-cycle regulators, p27(Kip1) (p27) is considered to be a potent tumor suppressor. To provide further molecular basis for understanding the progression of uterine leiomyoma, our objective was to evaluate the expression level of p27 in normal myometrium and uterine leiomyoma tissue and its effect on cytogenic growth. Western blot analysis, real-time polymerase chain reaction (PCR) and immunohistochemical staining revealed that p27 protein and messenger RNA were down-regulated in uterine leiomyoma tissue and cultured cells compared to normal myometrium. Full-length human p27 cDNA was transferred using a replication-deficient recombinant adenoviral vector (Ad.p27) into uterine leiomyoma cells and evaluated the effect on cell proliferation. Transfection of Ad.p27 into uterine leiomyoma cells resulted in the induction of apoptosis, reduction in viability and proliferation of uterine leiomyoma cells. Our results suggest a new paradigm that down-regulated p27 protein expression is the possible underlying mechanism for the growth of uterine leiomyoma and over-expression of p27 induces cell death. This study provides better understanding of the control exerted by p27 in regulating growth and disease progression of uterine leiomyoma.     

MicroRNA-139-5p Regulates Fibrotic Potentials via Modulation of Collagen Type 1 and Phosphorylated p38 MAPK in Uterine Leiomyoma

PurposeThis study aimed to elucidate whether microRNA-139-5p is involved in the pathogenesis of uterine leiomyoma.Materials and MethodsHuman leiomyoma and matched human smooth muscle samples were obtained from 10 women who underwent hysterectomy for uterine leiomyoma. MicroRNA (miRNA) expression was analyzed by quantitative real-time polymerase chain reaction. To assess the effects of miR-139-5p on cultured leiomyoma cells, cell migration, collagen gel contraction, wound healing, and the expression levels of hallmark proteins were evaluated in cells transfected with a miR-139-5p mimic.ResultsThe expression of miR-139-5p was significantly lower in leiomyoma tissues than in matched smooth muscle tissues. Restored miR-139-5p expression in miR-139-5p mimic-transfected human leiomyoma cells resulted in decreased contractility of the ECM and cell migration. In addition, upregulation of miR-139-5p decreased the protein expression of collagen type 1 and phosphorylated p38 MAPK.ConclusionExpression of miR-139-5p is downregulated in leiomyoma cells and modulation of miR-139-5p may be involved inthe pathogenesis of leiomyomas through the regulation of collagen type 1 and phosphorylated p38 MAPK. Therefore, miR-139-5p is a potential therapeutic target for leiomyoma.     

Progesterone receptor modulator CDB-2914 down-regulates vascular endothelial growth factor, adrenomedullin and their receptors and modulates progesterone receptor content in cultured human uterine leiomyoma cells

BACKGROUND: This study was conducted to evaluate the effects of graded concentrations (10(-8), 10(-7) and 10(-6) M) of progesterone receptor (PR) modulator CDB-2914 on the protein contents of PR, of vascular endothelial growth factor (VEGF), adrenomedullin (ADM) and their receptors in cultured human uterine leiomyoma and matching myometrial cells. METHODS: PR-A, PR-B, VEGF-A, VEGF-B, VEGF receptor (VEGFR)-1, VEGFR-2, ADM and ADM receptor (ADMR) contents were assessed by Western blot analysis. RESULTS: Treatment with 100 ng/ml progesterone increased VEGF-A, VEGF-B and ADM contents in cultured leiomyoma cells and normal myometrial cells. The concomitant treatment with 10(-6) M CDB-2914 significantly decreased the progesterone-induced VEGF-A, VEGF-B and ADM contents in cultured leiomyoma cells but not in normal myometrial cells. CDB-2914 treatment alone decreased VEGFR-1, VEGFR-2 and ADMR contents in cultured leiomyoma cells but not in normal myometrial cells. CDB-2914 treatment increased PR-A and decreased PR-B contents in cultured leiomyoma cells in a dose-dependent manner compared with untreated cultures, whereas no significant changes in PR isoform contents were observed in normal myometrial cells. CONCLUSIONS: These results suggest that CDB-2914 down-regulates VEGF, ADM and their receptor contents and modulates PR isoform contents in cultured leiomyoma cells in a cell-type-specific manner.     

膜联蛋白A5与宫颈黏膜上皮细胞癌变的关系

目的：确定在宫颈癌细胞系Hela细胞和SiHa细胞中是否有膜联蛋白A5(anxA5)的表达,为研究anxA5的功能及其与宫颈癌的关系奠定基础。方法：培养Hela细胞和SiHa细胞。TRIzol法提取细胞总RNA,RT- PCR法检测anxA5在mRNA水平的表达并将其基因片段连接于T载体,测序仪测序;Western印迹法和免疫细胞化学ABC法检测anxA5的表达。结果：两种宫颈癌细胞的RT-PCR结果和Western印迹法均显示目的条带;免疫细胞化学染色可见胞质和核膜被染成棕黄色;测序并经NCBI的BLAST进行比对,显示为人anxA5。结论：anxA5在宫颈癌细胞系Hela细胞和SiHa细胞的mRNA水平和蛋白质水平均有表达。     

Effects of luteolin, quercetin and baicalein on immunoglobulin E-mediated mediator release from human cultured mast cells

BACKGROUND: Flavonoids have a variety of activities including anti-allergic activities, and are known to inhibit histamine release from human basophils and murine mast cells. OBJECTIVE: The effects of luteolin, a flavone, on the immunoglobulin (Ig) E-mediated allergic mediator release from human cultured mast cells (HCMCs) were investigated and compared with those of baicalein and quercetin. METHODS: HCMCs were sensitized with IgE, and then treated with flavonoids before challenge with antihuman IgE. The amount of released mediators was determined as was mobilization of intracellular Ca2+ concentration, protein kinase C (PKC) translocation and phosphorylation of intracellular proteins were detected after anti-IgE stimulation. RESULTS: Luteolin, baicalein and quercetin inhibited the release of histamine, leukotrienes (LTs), prostaglandin D2 (PGD2), and granulocyte macrophage-colony stimulating factor (GM-CSF) from HCMC in a concentration-dependent manner. Additionally, the three flavonoids inhibited A23187-induced histamine release. As concerns Ca2+ signalling, luteolin and quercetin inhibited Ca2+ influx strongly, although baicalein did slightly. With regard to PKC signalling, luteolin and quercetin inhibited PKC translocation and PKC activity strongly, although baicalein did slightly. The suppression of Ca2+ and PKC signallings might contribute to the inhibition of mediator release. The activation of extracellular signal-regulated kinases (ERKs) and c-Jun NH2-terminal kinase (JNK), that were activated just before the release of LTs and PGD2 and GM-CSF mRNA expression in IgE-mediated signal transduction events, were clearly suppressed by luteolin and quercetin. In contrast, the flavonoids did not affect the activation of p38 mitogen-activated protein kinase (p38 MAPK) pathway. CONCLUSION: These results indicate that luteolin is a potent inhibitor of human mast cell activation through the inhibition of Ca2+ influx and PKC activation.     

Effect of scoparone on neurite outgrowth in PC12 cells

The neurite outgrowth-promoting effects of scoparone isolated from the stem bark of Liriodendron tulipifera were investigated in PC12 cells. At a concentration of 200 microM, scoparone markedly induced neurite outgrowth from PC12 cells. Scoparone at 200 microM also enhanced the outgrowth of neurites from cells in the presence of nerve growth factor (NGF, 2 ng/ml). The levels of intracellular cyclic AMP and concentration of Ca2+ were also increased by 200 microM scoparone. In addition, scoparone at 200 microM increased the activities of extracellular signal-regulated protein kinase (ERK), cyclic AMP-dependent protein kinase (PKA), protein kinase C (PKC) and Ca2+/calmodulin kinase II (CaMK II). However, scoparone-induced neurite outgrowth was blocked by a mitogen-activated protein kinase inhibitor (U0126), a PKA inhibitor (H89), a PKC inhibitor (GF109203X) and a CaMK II inhibitor (KN62). These kinase inhibitors also reduced the scoparone-induced neurite outgrowth associated with NGF. These results suggest that scoparone can induce neurite outgrowth by stimulating the upstream steps of ERK, PKA, PKC and CaMK II in PC12 cells.     

Association of breakpoint 14q23 with uterine leiomyoma

A chromosomal study of short-term cultured tumor cells from a benign uterine leiomyoma showed a clonal insertion, dir ins(14;6)(q23;p23p25) as a unique change. This finding supports the hypothesis of a specific association of the breakpoint 14q23 with uterine leiomyoma.     

Progesterone down-regulates insulin-like growth factor-I expression in cultured human uterine leiomyoma cells

BACKGROUND: Insulin-like growth factor-I (IGF-I) plays crucial roles in uterine leiomyoma cell growth through stimulating proliferation and inhibiting apoptosis. The present study was conducted to elucidate whether progesterone affects IGF-I and its receptor expression in cultured leiomyoma cells. METHODS: Isolated leiomyoma cells were subcultured in Phenol Red-free Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum for 120 h and then stepped down to serum-free conditions for an additional 48 h in the presence or absence of 17beta-estradiol (E(2)) (10 ng/ml) or progesterone (100 ng/ml). IGF-I and its receptor mRNA and immunoreactive IGF-I in the cultured cells were assessed by quantitative RT-PCR with Southern blot analysis and by radioimmunoassay with Seppak C18 chromatography, respectively. The presence of estrogen receptor (ER) and progesterone receptor (PR) in cultured leiomyoma cells was immunocytochemically examined. RESULTS: Both treatment with progesterone alone and treatment with E(2) and progesterone combined significantly decreased IGF-I mRNA and protein expression in cultured leiomyoma cells compared with that in untreated cultures, but treatment with E(2) alone did not. IGF-I receptor mRNA expression in those cells was not affected by treatment with either E(2) or progesterone. Immunocytochemical analysis revealed that PR protein expression in cultured leiomyoma cells maintained in a serum-free condition for 48 h whereas ER protein expression in the cells remarkably decreased after 24 h culture under the serum-free condition. CONCLUSIONS: The present study provided evidence for the first time that progesterone down-regulates IGF-I mRNA and protein expression in cultured leiomyoma cells without affecting IGF-I receptor mRNA expression.     

Progesterone receptor modulator CDB-2914 induces extracellular matrix metalloproteinase inducer in cultured human uterine leiomyoma cells

Effects of progesterone receptor modulator CDB-2914 on the expression of the extracellular matrix (ECM) components were examined in cultured human uterine leiomyoma and myometrial cells. ECM metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), tissue inhibitors of MMP (TIMPs) and collagen levels were assessed by Western blot analysis, MMP activity assay and real-time RT-PCR. RNA interference (RNAi) of EMMPRIN was performed using small interfering mRNA. In cultured leiomyoma cells, CDB-2914 treatment at concentrations greater than or equal to 10(-8) M significantly increased EMMPRIN, MMP-1 and MMP-8 protein contents and MMP-1, MMP-2, MMP-3 and MMP-9 mRNA levels, and activity of MMP-1, MMP-2, MMP-3 and MMP-9 in the medium. TIMP-1 and TIMP-2 were significantly decreased at mRNA and protein levels by CDB-2914 treatment at concentrations > or =10(-7) M in these cells. CDB-2914 treatment decreased types I and III collagen protein contents. However, CDB-2914 treatment did not affect the ECM component expression in cultured myometrial cells. RNAi of EMMPRIN abrogated CDB-2914-mediated both induction of MMPs and reduction of TIMPs and collagens in cultured leiomyoma cells. These results suggest that CDB-2914 modulates the expression of EMMPRIN, MMPs, TIMPs and collagens in cultured leiomyoma cells without comparable effects on myometrial cells.     

左炔诺孕酮下调survivin基因促进人子宫肌瘤细胞凋亡

目的探讨左炔诺孕酮(LNG)诱导人子宫肌瘤细胞(UtLMC)凋亡过程中survivin的表达变化。方法原代培养人子宫肌瘤细胞传代后,加入不同浓度LNG,以AO/EB双染法区分早、晚期凋亡细胞和坏死细胞;RT-PCR检测抑凋亡基因survivin mRNA的表达,Western blot测定survivin蛋白的表达。结果 10 mg/L LNG作用UtLMC后早期凋亡细胞多于阴性对照组,随着LNG剂量的增加,晚期凋亡细胞也逐渐增多,核浓聚、偏位,被染成桔红色;在10 mg/L以上LNG诱导的UtLMC凋亡中,survivin mRNA表达显著下降,蛋白表达由对照组的33.82±0.02下降至10.37±0.03(P<0.05)。结论一定浓度的左炔诺孕酮所诱导的人子宫肌瘤细胞凋亡,可能与抑制survivin抗凋亡活性相关。     

Human uterine leiomyoma cells: binding and growth responses to epidermal growth factor, platelet-derived growth factor, and insulin

The specific binding of epidermal growth factor (EGF), platelet-derived growth factor (PDGF) and insulin were measured in matching cultures of human leiomyoma and myometrial cells, along with the effects of these proteins on DNA and protein syntheses. Scatchard analyses of the binding data revealed that the EGF receptor sites/cell were significantly lower in leiomyoma than myometrial cultures. Two types of PDGF binding were observed when porcine PDGF was used, and one type was seen with human PDGF. By contrast to EGF, more PDGF receptor sites/cell were found in leiomyoma than myometrium but the receptor affinity was higher in the latter. Insulin binding was similar among the myometrial and leiomyoma cells. Protein synthesis was stimulated 3-fold by EGF, PDGF, or insulin in both cell types. DNA synthesis, was higher in myometrial than leiomyoma cells in the basal state and was stimulated by EGF, insulin, or PDGF. A synergistic stimulation (p less than 0.02) of DNA synthesis was observed in both myometrial and leiomyoma cells when EGF was added with insulin. The addition of PDGF with insulin caused only additive stimulation of DNA synthesis. However, the addition of EGF with PDGF caused a synergistic decrease (p less than 0.05) in DNA synthesis by myometrial but no leiomyoma cells. Cultures of human vascular smooth muscle cells obtained from umbilical veins gave results similar to those from myometrium. These findings single out the EGF receptor and EGF, or perhaps an EGF-like growth factor, and to a lesser degree PDGF, as potential regulators of uterine leiomyomata.     

Heparin inhibits proliferation of myometrial and leiomyomal smooth muscle cells through the induction of alpha-smooth muscle actin, calponin h1 and p27

Mast cells are widely distributed in human tissues, including the human uterus. However, the function of mast cells in uterine smooth muscle has not been clearly established. Mast cells possess secretory granules containing such substances as heparin, serotonin, histamine and many cytokines. To help establish the role of mast cells in the human myometrium, the action of heparin was investigated using smooth muscle cells (SMC) from normal myometrium and from leiomyoma. The proliferation of cultured myometrial and leiomyomal SMC was inhibited by heparin treatment. Flow cytometric analysis showed that the population in the G1 phase of the cell cycle increased under heparin treatment. Western blotting analysis showed that markers of SMC differentiation such as alpha-smooth muscle actin (alpha-SMA), calponin h1 and cyclin-dependent kinase inhibitor p27 were induced by heparin, whereas cell-cycle-related gene products from the G1 phase of the cell cycle, such as cyclin E and cdk2, were not changed. Taken together, these results indicate that heparin inhibits the proliferation of myometrial and leiomyomal SMC through the induction of alpha-SMA, calponin h1 and p27. We suggest that heparin from mast cells may induce differentiation in uterine SMC and may influence tissue remodelling and reconstruction during physiological and pathophysiological events.     

Signal transduction in human endothelial cells induced by their interaction with group B Streptococci

The molecular mechanisms underlying entry of group B Streptococci (GBS) into human endothelial cells are not yet fully understood. This study is centered on the triggering of signaling cascade in human umbilical vein endothelial cells (HUVEC) during their interaction with different GBS serotypes/strains (type III: 80340-vagina and 90356-CSF and type V: 88641-vagina and 90186-blood). We have shown that the analyzed microorganisms adhere to HUVEC, but only those of the strains 90356-CSF, 88641-vagina and 90186-blood presented intracellular viability. Activation of PKC directly increased F-actin content and organization into stress fibers, and increased intracellular viability of GBS-III microorganisms. PKA inhibitor seems to promote surveillance of GBS type V microorganisms within HUVEC. These studies indicate that different molecules present at the cell surface of the GBS might induce different responses to HUVEC, interfering with the recruitment of cortical actin filaments.     

蛋白激酶C活性下调对钙库操纵的钙通道活性和气道平滑肌细胞增殖的作用

目的:研究蛋白激酶C(PKC)活性下调对大鼠气道平滑肌细胞(ASMCs)的Ca2+库操纵的Ca2+通道(SOC)和ASMCs增殖的影响。方法:分离培养大鼠支气管平滑肌细胞;利用激光共聚焦显微镜测定ASMCs的fluo-3/AM的荧光信号;利用长时间暴露于PKC活化剂诱导PKC活性下调,观察PKC活性下调对ASMCs的SOC通道和增殖的影响;Alamar blue还原率测定法测定ASMCs的增殖。结果:PKC激活剂PMA(10μmol/L)和PDBu(1μmol/L)作用24h下调PKC活性后可以抑制ASMCs的增殖,PKC抑制剂chelerythrine同样抑制ASMCs的增殖;PKC活性下调和chelerythrine均可以抑制ASMCs的SOC通道活性;小剂量PKC激活剂PMA(100nmol/L)可以促进ASMCs的增殖,这种作用被SOC通道抑制剂SKF-96365抑制。结论:PKC活性下调或抑制导致SOC通道的活性下降,表明PKC可能参与了SOC通道功能调控;SOC通道开放可能参与了PKC促进ASMCs增殖的作用。     

A novel selective progesterone receptor modulator asoprisnil (J867) down-regulates the expression of EGF, IGF-I, TGFbeta3 and their receptors in cultured uterine leiomyoma cells

BACKGROUND: This study was conducted to evaluate the effects of a novel selective progesterone receptor modulator (SPRM) asoprisnil on the expression of growth factors and their receptors and on growth factor-induced proliferation of cultured uterine leiomyoma and matching myometrial cells. METHODS: The expression of epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I) and transforming growth factor (TGFbeta3) was assessed by immunocytochemistry and semi-quantitative RT-PCR. The expression of phosphorylated EGF receptor (p-EGFR), IGF-I receptor alpha subunit (IGF-IRalpha) and phosphorylated TGFbeta receptor type II (p-TGFbeta RII) was assessed by Western blot analysis. Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. RESULTS: Treatment with 10(-7) M asoprisnil decreased EGF, IGF-I and TGFbeta3 mRNA and protein expression as well as p-EGFR, IGF-IRalpha and p-TGFbeta RII protein expression in leiomyoma cells cultured for 72 h. EGF (100 ng/ml), IGF-I (100 ng/ml) and TGFbeta3 (10 ng/ml) increased the number of viable leiomyoma cells cultured for 72 h, whereas the concomitant treatment with 10(-7) M asoprisnil antagonized the growth factor-induced increase in leiomyoma cell proliferation. In cultured myometrial cells, however, asoprisnil affected neither the growth factor and their receptor expression nor the cell proliferation. CONCLUSION: Asoprisnil inhibits the expression of EGF, IGF-I, TGFbeta3 and their receptors in cultured leiomyoma cells without affecting their expressions in myometrial cells.     

Effects of polyunsaturated fatty acids on interleukin-2-dependent T cell growth

Cellular membranes, in addition to serving as structural constituents of cells, also provide precursors for a number of chemical messengers involved in intracellular signal transduction. This includes the eicosanoids (prostaglandins and leukotrienes) and diacylglycerol, and activator of protein kinase C (PKC). Changes induced in the fatty acid profile of lymphocytes can influence vital metabolic processes in cells. Such changes, independent of the function of fatty acids as prostaglandin and leukotriene precursors, can alter the development and regulation of immune responses. In this report we study the effects of the polyunsaturated fatty acids (PUFA) on proliferation and signal transduction in the interleukin-2 (IL-2)-dependent murine T cell line CTL.L-2. Culture of CTL.L-2 cells in the presence of specific PUFA resulted in their incorporation into the cellular phospholipids. IL-2-induced proliferation of CTL.L-2 cells was markedly suppressed in a dose-dependent fashion by incubation in media supplemented with dihomogammalinolenic acid (an n-6 PUFA) slightly inhibited proliferation, while eicosapentaenoic acid (an n-3 PUFA) had no effect. Neither indomethacin (a cyclooxygenase inhibitor) nor nordihydroguaiaretic acid (NDGA, a lipoxygenase inhibitor) reversed the effect of DGLA. In contrast, phorbol 12-myristate 13-acetate (a phorbol ester and activator of PKC), blocked, in a dose-dependent manner, the antiproliferative effect of DGLA. This study presents evidence that PUFA alter signal transduction in cells in a manner which is separate from their function as eicosanoid precursors. The botanical lipid-derived DGLA has a potent suppressive effect on IL-2-driven T cell proliferation and may alter signal transduction by modification of second messenger or PKC activity.