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.     

Progesterone, estradiol and their receptors in leiomyomata and the adjacent normal myometria of black Kenyan women

The contents of progesterone and oestrogen, and their respective receptors in uterine leiomyomata and adjacent normal myometrial tissue in indigenous black women in Kenya were studied. A random selection of twenty women undergoing hysterectomy for uterine fibroids at Kenyatta National Hospital was used for the studies. The myometria contained higher levels of E(2 ) (181% : P < 0.001); and P(4 ) (240.6 % : P < 0.001); as compared to the leiomyomata. On the other hand uterine leiomyomata contained significantly higher levels of ER (147.6% : P < 0.001); and PR (178.7% : P < 0.001 ); than normal myometria. These findings differ slightly from those reported in black women in developed countries, but support the proposal that manipulation of sex steroids may be useful in the treatment and management of uterine leiomyomata.     

SC58125对HepG-2细胞增殖和凋亡的影响

目的：探讨SC-58125对HepG-2细胞增殖和凋亡的作用及其分子机理。方法：应用细胞培养、MTT、TUNEL、流式细胞光度术、琼脂糖凝胶电泳及Western blot等方法研究SC-58125对HepG-2细胞增殖和凋亡的作用及其分子机理。结果：SC58125抑制HepG-2细胞的增殖、诱导其凋亡及引起G₀/G₁期阻滞，S期抑制。并使P33^cdk2、P34^cdc2、cyclinB₁、cyclinE、Mpm-2、Rb、PCNA 7种蛋白水平下降。结论：SC58125抑制HepG-2细胞的增殖及诱导其凋亡，可能与P33^cdk2、P34^cdc2、cyclinB₁、cyclinE、Mpm-2、Rb、PCNA 7种蛋白水平的下降有关。     

Opioid peptides inhibit the action of oestradiol on human myometrial cells in culture.

The effect of opioid peptides on cultured, oestradiol-stimulated human myometrial cells was examined. Oestradiol increased cell densities in mixed-cell (smooth muscle cells + stromal fibroblasts) cultures by 40%. This oestradiol-induced stimulation of cell proliferation was decreased to control values by D-met2-pro5-enkephalinamide. The half-effective inhibitory concentration of enkephalinamide was 0.3 nmol/l. The opioid-induced inhibition of cell proliferation was blocked completely by the specific opiate receptor antagonist naloxone, while naloxone did not have any effect on its own. This opioid effect was mediated dominantly by the mu opiate receptor. The optimal concentration for oestradiol to stimulate uterine cell proliferation was 2.2 nM. The basal rate of cell proliferation was not affected by enkephalinamide. In saturation experiments, the parameters of specific [3H]-naloxone binding were: dissociation constant = 1.02 nM, maximal binding capacity = 2910 binding sites/cell, Hill coefficient = 1.029. In human myometrial pure smooth muscle cell cultures, oestradiol decreased the proliferation of cells. Progesterone potentiated these oestradiol effects, but had no effect on its own. Enkephalinamide was also able to block the effects of oestradiol, but naloxone did not antagonize it. In summary, here we present a novel inhibitory role of endogenous opioid peptides in the regulation of cell growth and proliferation in the human uterus.     

Growth dynamics of human leiomyoma cells and inhibitory effects of the peroxisome proliferator-activated receptor-gamma ligand, pioglitazone

Uterine leiomyomas (fibroids) are the most frequent tumour of the female reproductive tract and are the primary cause of hysterectomies in women worldwide. Effective treatment options are few. In a search for alternative treatments, we have established primary cultures of human leiomyoma cells and adjacent myometrial tissues, and documented their growth dynamics in response to estradiol (E2) and pioglitazone (PIO), a peroxisome proliferation-activated receptor-gamma (PPARgamma) ligand, currently in clinical use for type II diabetes mellitus. Human uterine primary cell cultures display morphology and desmin content consistent with their smooth muscle origin. Surprisingly, leiomyoma cells exhibited slower proliferation patterns relative to matched myometrial cells, both in the absence and presence of E2, suggesting that tumour genesis may not be because of increased growth potential but could be related to suppression of growth-inhibiting factors in vivo. PIO significantly inhibited the cell proliferation of both myometrial and leiomyoma cells in a dose-dependent manner. Our results suggest the possibility of using PPARgamma ligands, such as PIO, as therapeutic agents for the conservative management of uterine fibroids.     

Mechanical stretch regulates TRPC expression and calcium entry in human myometrial smooth muscle cells

Stretch is known to stimulate myometrial hyperplasia and hypertrophy in early pregnancy and uterine contraction at term. We propose that transduction of the stretch signal involves alteration of intracellular calcium signalling, including changes in transient receptor potential canonical (TRPC) isoform expression. The aim of the present study was to investigate the effect of prolonged mechanical (tonic) stretch in vitro on human myometrial smooth muscle cell calcium signalling and TRPC expression. Cells were cultured from myometrial biopsies, obtained from women undergoing elective Caesarean section at term, grown on Flexiplates and subjected to 25% tonic mechanical stretch for 1, 4 and 14 h. Time-matched control cells were not stretched. Mechanical stretch (14 h) increased basal calcium entry and cyclopiazonic acid (CPA)-induced calcium/Mn(2+) entry (P < 0.05) in Fura-2 loaded cells. The calcium selectivity of CPA-thapsigarin induced inward currents, measured by patch clamp electrophysiology, was also increased in stretched cells compared with control cells (P < 0.05). Real time PCR and Western blot data demonstrated that TRPC3 and TRPC4 mRNA and TRPC3 protein expression were increased by stretch (P < 0.05), respectively. These data support the hypothesis that uterine stretch modulates uterine growth and contractility in pregnancy via alterations in calcium signalling.     

Rodent model of reproductive tract leiomyomata. Establishment and characterization of tumor-derived cell lines.

Uterine myometrial tumors are the most commonly found gynecological neoplasm in women. The underlying causes of uterine leiomyomata are poorly understood, a result in part of the absence of a good animal model system in which to study these tumors. This report describes a novel rat model (Eker rat) in which spontaneous gynecological smooth muscle tumors arise with a high frequency. Leiomyomas are the predominant reproductive tract tumor that arise in these animals, although leiomyosarcomas have also been observed. Cell lines have been established from both the benign and malignant lesions. All of the lines express smooth muscle-specific actin, and leiomyoma-derived cell lines express desmin. Two of the cell lines are tumorigenic in nude mice, and the lines are variable for expression of estrogen and progesterone receptors. These lines are the first rodent tumor-derived lines to be established from leiomyomata and are the only lines available from a hereditary form of these tumors. Together with Eker rats that spontaneously develop leiomyomata, they constitute an in vitro/in vivo model system for gaining insights into the mechanism of transformation of uterine smooth muscle cells and the role of steroid hormones and hormone receptors in myometrial tumorigenesis.     

Selective progesterone receptor modulator asoprisnil down-regulates collagen synthesis in cultured human uterine leiomyoma cells through up-regulating extracellular matrix metalloproteinase inducer

BACKGROUND: A recent clinical trial demonstrated that selective progesterone receptor modulator asoprisnil is effective in reducing uterine leiomyoma volume. We investigated the effects of asoprisnil in vitro on the expression of the extracellular matrix (ECM)-remodeling enzymes and collagens in cultured leiomyoma and matching normal myometrial cells. METHODS: The expression of extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), tissue inhibitors of MMP (TIMPs) and collagens were assessed by western blot analysis. RESULTS: Untreated cultured leiomyoma cells had significantly lower EMMPRIN (P < 0.05), MMP-1 (P < 0.05) and membrane type 1-MMP (MT1-MMP) (P < 0.01) protein contents, but significantly higher TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.05) and type III (P < 0.01) collagen protein contents compared with untreated cultured myometrial cells. Treatment with asoprisnil at concentrations > or =10(-7) M for 48 h significantly (P < 0.05) increased EMMPRIN, MMP-1 and MT1-MMP protein contents, and decreased TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.01) and type III (P < 0.05 at 10(-7) M; P < 0.01 at 10(-6) M) collagen protein contents in cultured leiomyoma cells compared with control cultures. However, asoprisnil treatment did not affect the protein contents of ECM-remodeling enzymes and collagens in cultured myometrial cells. CONCLUSIONS: These results suggest that asoprisnil may reduce collagen deposit in the ECM of cultured leiomyoma cells through decreasing collagen synthesis and enhancing the expression of EMMPRIN, MMPs and TIMPs without comparable effects on cultured myometrial cells.     

Induction of superoxide dismutase by decidualization in human endometrial stromal cells

The present study was undertaken to investigate the effect of decidualization on superoxide dismutase (SOD) expression in human endometrial stromal cells (ESC). To induce decidualization, isolated ESC were incubated with medroxyprogesterone acetate (MPA, 10(-6) mol/l) and oestradiol (10(-8) mol/l) for 23 days. Insulin-like growth factor-binding protein-1 (IGFBP-1) was used as a marker of decidualization. SOD mRNA in ESC was significantly increased on day 12 of the hormone treatment (P < 0.01), which was concomitant with the onset of IGFBP-1 mRNA expression, and further increased until day 23 of the treatment in a manner similar to the change in IGFBP-1 expression. To examine the synergistic effect of human chorionic gonadotrophin (HCG) with MPA and oestradiol on SOD and IGFBP-1 expression, ESC were incubated with HCG in the presence or absence of MPA and oestradiol. HCG had no synergistic effect on SOD and IGFBP-1 expression. SOD activities in the decidualized endometrial tissue obtained from patients given oestradiol and progesterone for 7-10 days were significantly higher than those in the non-decidualized endometrial tissue from patients without the hormone treatment (P < 0.01). In conclusion, SOD expression in ESC was induced by MPA and oestradiol accompanied by decidualization, suggesting that SOD may play important roles in decidualization of ESC.     

The growth arrest-specific gene CCN5 is deficient in human leiomyomas and inhibits the proliferation and motility of cultured human uterine smooth muscle cells

Uterine fibroids (leiomyomas) are a major women's health problem. Currently, the standard for treatment remains hysterectomy, since no other treatment modalities can reduce both symptoms and recurrence. As leiomyomas are benign neoplasias of smooth muscle cells, we sought to understand the regulation of uterine smooth muscle cell mitogenesis by CCN5, a growth arrest-specific gene in vascular smooth muscle cells which is induced and maintained by heparin treatment. Using autologous human myometrial and leiomyoma smooth muscle cells, we demonstrate that the proliferation and motility of both cell types are inhibited by the overexpression of CCN5. Surprisingly, we show that even though CCN5 is induced by heparin in vascular smooth muscle cells, treatment with heparin does not induce CCN5 expression in human uterine smooth muscle cells. Furthermore, we examine CCN5 mRNA expression in 10 autologous pairs of human myometrial and leiomyoma tissues and determine that CCN5 is down-regulated in 100% of the leiomyoma tissues analysed when compared to their normal myometrial counterparts. Thus, our data strongly suggest that CCN5 may exert an important function in maintaining the normal uterine phenotype and that loss of the anti-proliferative protein CCN5 from normal myometrium may account, at least in part, for tumorigenesis.     

氯喹对人肺癌A549细胞周期阻滞及增殖抑制的机制

目的 探讨氯喹抑制人非小细胞肺癌A549细胞增殖、促进凋亡、阻滞细胞周期的作用及其分子机制。 方法 应用MTT法和流式细胞术分别检测氯喹对A549细胞增殖、细胞凋亡和细胞周期的影响;Western blotting检测氯喹对A549细胞周期蛋白(cyclin E1)和细胞周期蛋白依赖性激酶（CDK2）、肿瘤抑制蛋白PTEN以及细胞周期抑制蛋白P21、P27表达水平的影响。 结果 氯喹能够抑制A549细胞增殖,并且具有时间-剂量依赖性。氯喹可以诱导细胞凋亡,不同浓度的氯喹作用于A549细胞24h后,细胞凋亡率随着作用剂量的增加而升高。进一步的研究发现,氯喹还能够阻滞细胞周期于G₀/G₁期,降低cyclinE1和CDK2表达水平,明显提高PTEN、P21和P27的表达水平。 结论 氯喹具有抑制肺癌细胞增殖、促进其凋亡和阻滞细胞周期的作用,其机制可能与其抑制CyclinE1和CDK2表达,并且上调PTEN、P21和P27蛋白的表达有关。     

微小RNA-146a 上调cyclin D1 表达诱导大鼠血管平滑肌细胞的增殖

目的:采用基因芯片技术研究小分子RNA-146a(miR-146a)促进血管平滑肌细胞增殖的作用靶点并进行验证。方法:原代培养大鼠血管平滑肌细胞,分成mimics 组、inhibitor 组、control 组、sham 组,分别体外转染miR-146a mimics(50nmol/ L)、miR-146a inhibitor(50 nmol/ L)、miR-146a 错义链(50 nmol/ L)、PBS,Real time PCR 测定转染后miR-146a 水平,CCK8法检测转染后血管平滑肌细胞增殖情况。采用基因芯片检测inhibitor 组和control 组基因表达谱,通过生物信息学技术筛选出差异基因和调控的信号通路。对筛选出来的信号通路用Real time PCR 和Western blot 进行验证。结果:转染48 h后,inhibitor 组血管平滑肌细胞的miR-146a 水平明显低于control 组和sham 组(P<0.01),inhibitor 组血管平滑肌细胞的OD 值明显低于control 组、sham 组(P<0.05)。通过对基因表达谱分析发现,p53 信号通路被miR-146a 上调。用Real time PCR 和Western blot进行检测发现,p53 信号通路中关键分子p53、caspase3、PTEN 的mRNA 和蛋白水平无明显变化(P>0.05),而mimics 组VSMC中cyclin D1 的mRNA 和蛋白水平增加(与sham 相比,P<0.05),inhibitor 组VSMC 中cyclin D1 的mRNA 和蛋白水平下降(与sham相比,P<0.05)。结论: miR-146a 可能通过上调细胞周期蛋白cyclin D1 的表达促进大鼠血管平滑肌细胞的增殖。     

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.     

miR-141表达异常对人肝癌细胞恶性生物学表型的影响

 目的: 研究微小RNA-141(miR-141)在人肝癌细胞和正常胎肝细胞中的表达,同时分析miR-141表达异常对人肝癌细胞恶性生物学表型的影响。方法: 分别提取人肝癌细胞SMMC-7721和正常肝细胞HL-7702的总RNA,采用实时荧光定量PCR法检测miR-141的表达。采用脂质体介导的转染方法分别将miR-141 mimic转染SMMC-7721细胞,将miR-141 inhibitor转染HL-7702细胞;MTS试剂盒和BrdU-ELISA检测细胞增殖能力,流式细胞术检测转染前后细胞周期和凋亡率的变化。Transwell实验检测miR-141表达变化对细胞体外迁移能力的影响。结果: miR-141在SMMC-7721细胞中的表达较HL-7702细胞明显下降。与空白组、脂质体组和阴性对照组相比,转染25 nmol/L miR-141 mimic的SMMC-7721细胞中,细胞增殖速度减慢,S期细胞比例降低,凋亡细胞比例上升,细胞体外迁移能力下降;转染50 nmol/L miR-141 inhibitor的HL-7702细胞中,细胞增殖速度加快,S期细胞比例上升,凋亡细胞比例下降,细胞体外迁移能力增强。结论: miR-141在人肝癌细胞中表达下降,上调miR-141表达可抑制肝癌细胞体外增殖活性和迁移能力,影响细胞周期和凋亡。在肝癌发病进程中,miR-141可能扮演抑癌基因的角色。     

临产前后子宫平滑肌细胞内游离钙含量的变化

目的:探讨临产前后子宫平滑肌细胞内游离Ca²⁺含量变化。方法:应用特异性Ca²⁺荧光指示剂Fluo-3AM,对19例未临产和23例临产足月妊娠孕妇,剖宫产子宫下段平滑肌细胞进行负载,结合激光扫描共聚焦显微镜测定子宫平滑肌细胞内游离Ca²⁺分布状态及其浓度变化规律。结果:Ca²⁺在子宫平滑肌细胞胞浆内呈弥漫分布的颗粒状红色荧光物质,在未临产平滑肌细胞中分布和荧光强度均较弱,在临产子宫平滑肌细胞中明显增强。在未临产和临产子宫平滑肌[Ca²⁺]i分别为(35±8.1)nmol/L和(75±7.3)nmol/L,二者静息状态下子宫平滑肌[Ca²⁺]i差异显著(P＜0.05)。结论:分娩前后子宫平滑肌细胞内游离Ca²⁺含量的变化,可能为宫缩发生发展过程复杂的重要事件和分子机制之一。