Altered apoptosis and proliferation in endometrial stromal cells of women with adenomyosis

BACKGROUND: The eutopic endometrium in a woman suffering from adenomyosis is known to be biologically different from that of healthy women. The aim of this study was to examine the apoptosis and proliferation of eutopic endometrium from women with adenomyosis. METHODS: We enrolled 23 women with adenomyosis (study group) and 21 without (control group). Eutopic endometrium was obtained and separated into single endometrial stromal cells (ESCs). ESCs were treated in vitro with hydrogen peroxide (H(2)O(2)) to examine their apoptosis using a fluorescence-activated cell sorter. Cells were also treated with estradiol (E(2)), medroxyprogesterone acetate, interleukin (IL)-6, lipopolysaccharide and interferon-gamma (IFN-gamma) to test their proliferation using a non-radioactive cell proliferation assay. RESULTS: The percentage of annexin V ( + )/7-amino-actinomycin D ( + ) ESCs was much lower in women with adenomyosis after 24 h culture with and without H(2)O(2) treatment when compared with the control group. ESCs of adenomyosis proliferated more rapidly than those of the control group, whether they were cultured alone or were treated with E(2), MPA, IL-6 or IFN-gamma. The immunocytochemical Ki-67 labelling index was much more prominent in adenomyotic ESCs than that of the control group (7.7% versus 1.1%, P < 0.001). CONCLUSIONS: Altered apoptosis and proliferation of eutopic endometrium possibly elucidate some aspects of the pathophysiology of adenomyosis. A high Ki-67 labelling index in immunocytochemistry might be a potential indicator in predicting the occurrence of adenomyosis.     

IL-22 in the endometriotic milieu promotes the proliferation of endometrial stromal cells via stimulating the secretion of CCL2 and IL-8

Interleukin-22 (IL-22) is a member of the IL-10 cytokine family and plays critical roles in inflammation, immune surveillance, and tissue homeostasis. However, whether IL-22 regulates the growth of endometrial stromal cells (ESCs), and participates in the pathogenesis of endometriosis remain unclear. In this study, we found that the expression of IL-22 and it receptors (IL-22R1 and IL-10R2) in eutopic endometrium and ectopic lesion of women with endometriosis was higher than that from healthy control. Recombinant human IL-22 (rhIL-22) stimulated the proliferation of ESCs in a dosage-dependent manner. On the contrary, anti-human IL-22 neutralizing antibody inhibited the proliferation of ESCs in vitro. The stimulatory effect of IL-22 on the proliferation of ESCs could be reversed by inhibitor of STAT5, ERK1/2 or AKT signal pathway. However, blocking STAT3, JNK or P38 signal pathway had no these effects. By Enzyme-linked immunosorbent assay (ELISA) and flow cytometry assay, we demonstrated the rhIL-22 not only stimulate the secretion of CCL2 and IL-8, but also significantly up-regulate the expression of IL-8 receptor CXCR1 on ESCs. Meanwhile, STAT5, ERK1/2 and or AKT signal inhibitors could abrogate the increase of CCL2, IL-8 and CXCR1 levels induced by rhIL-22. However, rhIL-22 had not similar influence on CCL2 receptor CCR2. Our current results suggested that the higher level of IL-22 and it receptors in eutopic endometrium may stimulate the expression of CCL2, IL-8/CXCR1, and further promote the growth of ESCs possibly through activating STAT5, MAPK/ERK1/2 and or AKT signal pathways, which may be involved in the occurrence and development of endometriosis.     

Uterus and endometrium: Inhibition of human endometrial stromal cell proliferation by interleukin 6

We investigated the ability of interleukin 6 (IL-6) to modulatehuman endometrial stromal cell growth in vitro Stromal cellproliferation in response to treatment with varying concentrationsof IL-6 was determined. Endometrial tissue was obtained from10 normally cycling women during the secretory phase of theirmenstrual cycle. Treatment with IL-6 resulted in a dose- andcell-density-dependent inhibition of endometrial stromal cellproliferation in vitro. The maximal inhibition was observedwith 200 pg/ml of IL-6 and at a concentration of 10⁵ cells/well.During in-vitro culture, stromal cells produced low amountsof IL-6 and demonstrated the presence of IL-6 receptor. Thesedata demonstrate that IL-6 acts as a growth-regulatory signalfor human endometrial stromal cells. We postulate that IL-6may contribute to the maintenance of homeostasis in normal endometriumand that perturbation of IL-6 mediated responses may play arole in disorders of the endometrium such as endometrial cancerand endometriosis.     

Involvement of insulin-like growth factor-binding protein-related protein 1 in decidualization of human endometrial stromal cells

Uterine decidualization is crucial for successful implantation and the establishment of pregnancy. In the present study, the expression of insulin-like growth factor-binding protein (IGFBP)-related protein 1 (IGFBP-rP1) in the human uterus and endometrial stromal cells (ESCs) and its physiological significance in decidualization were examined. IGFBP-rP1 protein was localized in the glandular epithelium and stromal cells, and blood vessels in the endometrium. Cultured stromal cells expressed IGFBP-rP1 and secreted it into the medium. IGFBP-rP1 was localized mostly in the cytoplasm near the nucleus. Knocking down the endogenous IGFBP-rP1 expression in stromal cells, by a small interfering (si)RNA, diminished the expression of prolactin and IGFBP-1 which serve as decidual markers. These results suggest that IGFBP-rP1 may play a role in decidualization of ESCs.     

Progesterone induces the fibulin-1 expression in human endometrial stromal cells

BACKGROUND: By using microarray analysis with human endometrial stromal cells (ESCs), we previously reported that the mRNA for fibulin-1, an extracellular matrix as well as a plasma glycoprotein, is up-regulated by progesterone. In the present study, we tried to clarify the spatial and temporal regulation mechanism of fibulin-1 in the human endometrium. METHODS AND RESULTS: Quantitative analysis with real-time PCR experiments on human endometrial tissues showed significantly higher fibulin-1 mRNA expressions in secretory phase endometria than in proliferative phase. Immunohistochemical studies revealed that the fibulin-1 protein is expressed in the glandular epithelium in proliferative phase endometria, and that expression switched to the stroma in secretory phase endometria. In culture experiments with ESCs, a significant increase of fibulin-1 mRNA expression was observed in cells treated with 6 alpha-methyl-17 alpha-hydroxy-progesterone acetate (MPA) or 8 bromoadenosine 3':5'-cyclic monophosphate (8-Br-cAMP). MPA stimulated the fibulin-1 mRNA expression in a dose-dependent manner, and a progesterone antagonist, RU-486, inhibited the stimulatory effect almost completely. By contrast, beta-estradiol alone did not increase the fibulin-1 mRNA expression. CONCLUSIONS: These results suggest that fiblin-1 is an important molecule that mediates progesterone action in human ESC differentiation towards implantation.     

Lidocaine inhibits proliferation and induces apoptosis in colorectal cancer cells by upregulating mir-520a-3p and targeting EGFR

Lidocaine is a conventional local anesthetic which is shown antiproliferative of colorectal cancer (CRC) in patients. MicroRNAs (miRNAs) have been consistently demonstrated to be involved in CRC, and miR-520a-3p could suppress CRC migration, promote apoptosis by targeting epidermal growth factor receptor (EGFR). However, the mechanism by which lidocaine regulated CRC proliferation and apoptosis remains unknown. In this study, quantitative RT-PCR were used to measure miR-520a-3p and EGFR expression levels, and western blotting assays ware performed to measure EGFR expression in CRC cells. Luciferase reporter assay was employed to validate the direct targeting of EGFR by miR-520a-3p. Cell proliferation and apoptosis assays ware utilized to analyze the role of lidocaine in CRC cells. The results indicated that 500 and 1000 μM lidocaine over 24?h inhibited proliferation and induced apoptosis of CRC cells. Compared with the control group, the expression of EGFR was suppressed by lidocaine (500 μM) in CRC cells. Furthermore, miR-520a-3p could directly targets EGFR in CRC cells. Lidocaine (500 μM) increased the expression of miR-520a-3p and rescued the reduction of miR-520a-3p caused by miR-520a-3p inhibitor. The results suggested that lidocaine could suppress the expression of EGFR by upregulating miR-520a-3p, and it could induce apoptosis and inhibit proliferation in CRC cells. Lidocaine may serve as potential therapeutic regimen for colorectal cancer.     

Effect of human endometrial stromal cell-derived conditioned medium on uterine natural killer (uNK) cells' proliferation and cytotoxicity

Citation Chen Y, Zhuang Y, Chen X, Huang L. Effect of human endometrial stromal cell‐derived conditioned medium on uterine natural killer (uNK) cells’ proliferation and cytotoxicity. Am J Reprod Immunol 2011; 65: 589–596 Problem Human endometrial stromal cells are involved in the regulation of immune cell proliferation, apoptosis, differentiation, and function. In the endometrium, uNK cells are in close contact with stromal cells. The aim of the study was to investigate the effects of human endometrial stromal cells on uNK‐cell proliferation and uNK‐cell cytotoxicity. Method of study The conditioned medium was derived from the endometrial stromal cells in the proliferative phase, secretory phase, and early pregnancy. The effects of stromal cell‐derived conditioned medium on uNK‐cell proliferation and cytotoxicity were detected by mitochondrial lactate dehydrogenase‐based MTS staining and flow cytometry. Results The stromal cell‐derived conditioned medium in both secretory phase and early pregnancy significantly promoted uNK‐cell proliferation. Compared with the control group, the uNK‐cell cytotoxicity were significantly reduced by conditioned medium in the proliferative, secretory, and decidua groups, but there were no significant differences among these different physiological stages in the inhibiting ability. Conclusion Human endometrial stromal cells may be involved in the regulation of uNK‐cell functions through influencing proliferation and cytolytic activity.     

Roles of p38 and c-jun in the differentiation, proliferation and immortalization of normal human endometrial cells

BACKGROUND: It has been reported that p38 and c-jun operateas mediators of cell proliferation and differentiation. Therefore,by studying the roles of c-jun and p38 in the proliferationand differentiation of normal human endometrial cells, we canbetter understand the mechanism of these processes in endometrialcells. METHODS: Separation of glandular and stromal componentswas based on a modification of the work of Satyaswaroop et al.To confirm the purification of the endometrial cells and theexpression of the transfected SV40 large T antigen, immunocytochemicalanalysis and western blot analysis were performed. RESULTS:There were polygonal shapes in the stromal cells in the earlypassage 1–2, while the aged endometrial stromal cellswere spindle shaped. To investigate passage-dependent molecularevents in endometrial cells, the c-jun and pp38 levels wereexamined. Both c-jun and pp38 were significantly reduced withcellular aging and passages. To understand the role of c-jun,endometrial stromal cells were treated with SP600125 which isa specific inhibitor of c-jun. SP600125 induced morphologicalchanges of young endometrial stromal cells with polygonal shape;the young cells appeared as aged endometrial cells with spindleshape. In addition, an immortalized endometrial cell line wasestablished and shown to express activated c-jun, similiar tonormal endometrial cells. CONCLUSIONS: These results suggestthat the modulation of p38 and c-jun may play an important rolein the differentiation and proliferation of human endometrialcells.     

L-22 enhances the invasiveness of endometrial stromal cells of adenomyosis in an autocrine manner

It has reported that interleukin-22 (IL-22) promotes the invasion of tumor cells. IL-22 in the endometriotic milieu stimulates the proliferation of human endometrial stromal cells (ESCs). The present study aimed to elucidate whether and how IL-22 regulates the invasion of ESCs from adenomyosis. The expression of IL-22 and its receptors in normal endometrium, eutopic endometrium and ectopic lesion was analyzed by immunohistochemistry; the invasiveness of ESCs in vitro was verified by Matrigel invasion assay; and the effects of IL-22 on the correspondent functional molecules were investigated by ELISA and flow cytometry. Here we found that IL-22 and its receptors IL-22R1 and IL-10R2 in eutopic endometrium and ectopic lesion of adenomyosis were significantly higher than that of normal endometrium. Recombinant human IL-22 (rhIL-22) increased IL-22R1 and IL-10R2 levels on ESCs. Moreover, rhIL-22 promoted the invasiveness of ESCs, and inhibited the expression of metastasis suppressor gene CD82, stimulated the secretion of IL-8, RANTES, IL-6 and VEGF of ESCs. On the contrary, the neutralizing antibody for IL-22 reversed these effects. Our current study has demonstrated that IL-22 has a positive feedback on the expression of its receptors IL-22R1 and IL-10R2 on ESCs. This autocrine effect of IL-22 promotes the invasion of ESCs possibly through regulating invasion-related molecules, suggesting that the abnormal high expression of IL-22 may play an important role in ESCs invasion and finally contribute to the origin and development of adenomyosis.     

Pathogenetic role of the stromal cells in endometriosis and adenomyosis

Ten cases of endometriosis of bowel, ovaries, uterine serosa and 10 cases of adenomyosis were studied. Blocks of tissue with areas of interest were submitted for serial sectioning of the entire block. Some sections were immunostained for oestrogen receptor, vimentin, Ber-EP-4 and cytokeratins. The common finding was the presence of type 1 nodules, consisting of isolated nodules of endometrial stromal cells without endometrial glands, along blood or lymphatic vessels. The stromal cells showed positive immunoreactivities for oestrogen receptor and vimentin, and negative reactivities for cytokeratins. Due to the absence of connection with adjacent endometriosis or adenomyosis, it is likely that these endometrial stromal nodules arise from the multipotential pericytes. In addition, in serosa of all cases of endometriosis, type 2 nodules, having adjacent mesothelium (Ber-EP4 ?) changing into epithelium (Ber-EP4 +) and type 3 nodules, with non-endometrial epithelium (oestrogen receptor ?) changing into endometrial gland (oestrogen receptor +) were identified. We believe that the formation of type 1 nodules from the pericytes and the transformation of the mesothelium into endometrial glands in type 2 and 3 nodules are accomplished through the process of induction by the endometrial stroma, and the proliferation is controlled by genetic, hormonal and immunological factors. Type 1, 2 and 3 nodules are likely to represent a histological continuum in the development of early endometriosis. Subsequent to the formation of endometriosis in the serosa, the pathway of development of endometriosis and adenomyosis is similar. Through the processes of induction and proliferation there is an increase in size of the stroma of type 1 nodules and that of endometrial tissue with subsequent fusion of the stroma of type 1 nodules and that of foci of adenomyosis or endometriosis. Consequently, there is enlargement of the stroma of the foci of adenomyosis or endometriosis. The ‘newly enlarged stroma’ serves as ‘new soil’ for further growth of the endometrial glands in the endometrial tissue.     

Functional characterization of prostaglandin transporter and terminal prostaglandin synthases during decidualization of human endometrial stromal cells

BACKGROUND: Decidualization of endometrial stromal cells is essential for successful implantation and pregnancy. Prostaglandins (PG) have been shown to be required for the initiation and maintenance of decidualization in animal models. The transport of PG across the plasma membrane is mediated by carriers such as prostaglandin transporter (PGT). Our recent data have shown the expression of human PGT (hPGT) in the endometrium during the menstrual cycle. The objective of the present study was to characterize hPGT in decidualized stromal cells. METHODS AND RESULTS: Human endometrial stromal cells were treated with a combination of cAMP and medroxyprogesterone acetate to induce decidualization. Decidualization was confirmed by morphological differentiation and increased secretion of prolactin. A large increase in hPGT mRNA level, as measured by real-time PCR analysis, was observed in decidual cells compared with control. Similarly, a 2-fold up-regulation of hPGT and 3-12-fold increase in PG biosynthetic enzymes were obtained at the protein level. Decidual cells exhibited a higher isotopic PGE2 uptake and greater intracellular PG levels than control. CONCLUSIONS: The higher uptake of PG by decidual cells is highly likely to be mediated via hPGT. PGT is a newly identified regulator of PG action at the cellular level and likely contributes to the regulation of PG action in female reproductive processes.     

Apoptosis in endometrial glandular and stromal cells in women with and without endometriosis

BACKGROUND: The aetiology of endometriosis is unknown. Ectopic dissemination of the endometrial cells gives origin to endometriotic lesions, but occurs in women with and without endometriosis. It has been suggested that increased ectopic cell survival facilitates their implantation. The objectives of this study were to evaluate endometrial apoptosis in women with endometriosis according to: (i) cyclic changes, (ii) glandular and stromal contribution, and (iii) stage of the disease. METHODS: The subjects were women undergoing diagnostic laparoscopy and endometrial biopsies for suspected endometriosis. Spontaneous apoptosis was evaluated using TdT-mediated dUTP-biotin nick end-labelling (TUNEL) assay. Apoptotic cells per 10 mm(2) (apoptotic index) in an area of 10-50 mm(2) in 5 microm endometrial tissue sections were counted and location of these cells was recorded. RESULTS: The apoptotic index in glandular epithelium was lower in endometriosis than controls (26.0 +/- 5.5 versus 51.2 +/- 9.7, P = 0.03) but not in the stroma (36.3 +/- 6.4 versus 48.4 +/- 11.3, NS). In controls, apoptosis was highest during the late secretory/menstrual and early proliferative phases and cyclic variability was apparent. In endometriosis, this cyclic variability was lost. There was a trend toward decreased apoptosis with increasing stage of the disease, but the differences lacked statistical significance. CONCLUSIONS: Spontaneous apoptosis is decreased in the endometrial glands in women with endometriosis, especially during late secretory/menstrual and early proliferative phases of the cycle. This may indicate increased viability of endometrial cells shed during menses, facilitating their ectopic survival and implantation.     

miR-195靶向调控PDK4表达抑制肝癌细胞增殖和促进凋亡

目的 探讨miR-195调控PDK4表达在肝癌增殖和凋亡中的作用.方法 体外培养肝癌细胞,分别转染miR-195模拟物或阴性对照质粒Nc,转染48h后,MTT检测细胞增殖,流式细胞术检测细胞凋亡,划痕实验检测迁移能力,Western blot和PCR检测PDK4表达.采用双荧光素酶实验检测miR-195与PDK4的靶向调控关系.结果 转染miR-195可明显抑制肝癌细胞内PDK4的表达,抑制肝癌细胞增殖和迁移,促进细胞凋亡.HEPG2细胞转染miR-195 mimics后,细胞增殖率和细胞迁移能力较对照组和miR-NC组显著下降(P＜0.05);细胞凋亡率较对照组和miR-NC组显著升高,PDK4 mRNA及蛋白表达水平较对照组和miR-NC组显著下降(P＜0.05).Target Scan结果提示PDK4可能是miR-195的下游靶基因,miR-195能够抑制野生型PDK4 3'UTR报告基因载体的荧光素酶活性,但是对突变型PDK4 3'UTR无明显影响.结论 上调miR-195能靶向抑制PDK4,进而对肝癌细胞起抑制增殖、迁移和促进凋亡的作用.     

Progesterone-dependent release of transforming growth factor-beta1 from epithelial cells enhances the endometrial decidualization by turning on the Smad signalling in stromal cells

Endometrial decidualization results from the differentiationof stromal cells in an ovarian steroid-sensitive manner. Humanendometrial tissues obtained from fertile women at various stagesof the menstrual cycle were subjected to immunohistochemistryto localize the components of the transforming growth factor-beta(TGF-ß) system. TGF-ß receptor-I and -IIexpression was higher in stromal cells than in epithelial cellsduring the secretory phase while no such variation was observedduring the proliferative phase. The expression of phosphorylatedSmad3 (pSmad2/3), an activated form of a component of the TGF-ßsignalling pathway, and translocation of pSmad2/3 from the cytoplasmto the nucleus were more pronounced in secretory endometrium.In coculture of human endometrial epithelial with stromal cells,each isolated from the proliferative endometrium, administrationof progesterone stimulated decidualization as well as TGF-ßsignalling activation in stromal cells. Progesterone also significantlyelevated the concentration of TGF-ß1 in the coculturemedium. Careful manipulation of the coculture, i.e. selectiveaddition and omission of the cellular components, showed thatthis progesterone-induced increase in secretion of TGF-ß1come mainly from epithelial cells. Moreover, administrationof TGF-ß1 (10 ng/ml) directly to cultured stromalcells enhanced the expression of prolactin as well as pSamd2/3even without progesterone. Taken together, our present datasupport the notion that progesterone induces stromal decidualizationindirectly, i.e. by enhancing the expression and secretion ofTGF-ß1 from epithelial cells. The secreted, epithelial-derivedTGF-ß1 then acts on adjacent stromal cells, at leastin part, to turn on Smad signalling that could lead to stromaldecidualization.     

miR-101 suppresses tumor proliferation and migration,and induces apoptosis by targeting EZH2 in esophageal cancer cells

Aim: To investigate the role of miR-101 in the regulation of tumor proliferation, invasion, apoptosis and to its target gene in human ESCC. Methods: The expression level of miR-101 in Eca109 cell line was determined by real-time polymerase chain reaction (PCR). After transfected with miR-101 mimics and inhibitor, proliferation, migration and apoptosis in ESCC cell line (Eca109) were detected by MTT, cell wound healing assay and flow cytometry, respectively. The expression of EZH2 in Eca109 cell was examined by immunohistochemical staining. Results: We found that miR-101 was significantly down-regulated in ESCC cell than in matched normal esophageal epithelium cell. The expression level of miR-101 was inversely correlated to EZH2 protein expression in ESCC cell. In Eca109 cells, over-expression of miR-101 significantly inhibited the migration and invasion of ESCC cells, and promotes cell apoptosis. Conclusions: These findings suggest that decreased expression of miR-101 might promote metastasis of human ESCC by inducing accumulation of EZH2 protein.     

Expression of focal adhesion kinase in endometrial stromal cells of women with endometriosis was adjusted by ovarian steroid hormones

The aim of our study is to investigate the effects of ovarian steroid hormones on focal adhesion kinase (FAK) expression in ESCs and whether there is alteration in women with endometriosis. FAK expression was assessed by western blotting analysis. Elevated expression of FAK was seen in the cultured ESCs treated with estrogen (P < 0.05). Expression of FAK protein was not changed in ESCs after treated by progesterone or treated by estrogen and progesterone. The level of up-regulation by estrogen in endometriosis is significantly higher than that from women without endometriosis (P < 0.05). FAK expression in endometrial stromal cells from endometriosis was more sensitive to estrogen, which might contribute to the pathogenesis and progress of endometriosis.