Invasion Of Endometrial Carcinoma Cells Research Articles

Influence of Epidermal Growth Factor Receptor Inhibitor AG1478 on Epithelial-Mesenchymal Transition in Endometrial Carcinoma Cells

To analyze the influence of epidermal growth factor receptor inhibitor AG1478 on the proliferation and epithelial-mesenchymal transition in endometrial carcinoma cells. The inhibitory effect of different concentrations of AG1478 on the proliferation of endometrial carcinoma cells was detected by tetrazolium-based assay. Western blot was applied to investigate the influence of AG1478 on expressions of epithelium-cadherin, α-catenin, neural cadherin, vimentin, matrix metalloproteinase 9 (MMP9), and MMP2 protein in endometrial carcinoma cells. The influence of AG1478 on migration and invasion of endometrial carcinoma cells was examined by Transwell migration and invasion assay, respectively. AG1478 could suppress the proliferation of different endometrial carcinoma cells, and cells transfected with epidermal growth factor receptor were more sensitive (P < 0.05). The expression of an increase in epithelial marker proteins and a decrease in mesenchymal marker proteins, MMP9, MMP2 were observed in endometrial carcinoma cells after AG1478 treated. This effect was more obvious in cells transfected with epidermal growth factor receptor (P < 0.05). The migration and invasion ability of endometrial carcinoma cells were suppressed by AG1478, and Ishikawa cells transfected with epidermal growth factor receptor were demonstrated to be more sensitive to AG1478 (P < 0.05). Epidermal growth factor receptor inhibitor AG1478 could effectively inhibit the proliferation and epithelial-mesenchymal transition of endometrial carcinoma cells.

Insulin promotes proliferation, survival, and invasion in endometrial carcinoma by activating the MEK/ERK pathway

The involvement of insulin in endometrial carcinoma (EC) was investigated using radioimmunoassay, Western blot, immunoprecipitation, MTT, and Annexin V-FITC/PI assays in tissue samples and cultured cells. Serum levels of insulin, p-p52Shc, p-p46Shc, Shc·Grb2 complexes, p-MEK, p-ERK, and cyclin D1 were elevated in patients with EC. Expression of key proteins in the MEK/ERK pathway, including p-p52Shc, Shc·Grb2 complexes, p-MEK, p-ERK, and cyclin D1, was significantly higher in patients with advanced FIGO stage, high grade, and lymph-node metastasis and correlated positively with serum insulin concentration. Insulin promotes Ishikawa 3-H-12 cell proliferation, survival, and invasion, and these effects induced by insulin were significantly blocked by MEK inhibitor PD98059. Insulin thus promotes EC cell proliferation, survival, and invasion via the MEK/ERK pathway.

Prognostic significance of Notch signalling molecules and their involvement in the invasiveness of endometrial carcinoma cells

The aim of this study was to investigate the significance of the expression of Notch-related molecules in endometrial carcinoma. The expression of Notch receptors (Notch1 and 3) and Notch ligands [Jagged (JAG) 1 and Delta-like (DLL) 4] was examined immunohistochemically in 37 normal and 76 malignant endometrial tissue samples. For each section, immunohistochemical staining was scored using a positivity index (PI, full score; 200). The effects of a Notch inhibitor, DAPT, on cell proliferation, invasion and motility were investigated using endometrial carcinoma cell lines. The PIs for Notch1 (mean±SD 90.4±15.3), Notch3 (95.6 ± 20.4), JAG1 (95.5±10.0) and DLL4 (88.2±9.6), were significantly higher in endometrial carcinoma than normal endometrium. The PI for Notch1 was associated significantly with advanced International Federation of Gynecologists & Obstetricians (FIGO) stage. In addition, patients with tumours showing high expression of both Notch1 and JAG1 had a poor prognosis compared with those having double-negative carcinomas (P=0.015). DAPT suppressed invasiveness of cells derived from the endometrial carcinoma cell line KLE. The Notch1-JAG1 axis may enhance the invasive properties of endometrial carcinomas, which suggests the Notch pathway may be a promising target for the treatment of this malignancy.

Abstract 1538: Inhibition of adenosine-mediated stabilization of intercellular adhesions promotes hypoxia-stressed endometrial carcinoma cell metastasis

Abstract Hypoxic microenvironments are commonly encountered in multiple epithelial malignancies. Epithelial cells classically up-regulate cellular adhesive mechanisms to counter the noxious effects of hypoxia. Inhibiting these tissue protective mechanisms is necessary for carcinoma cell invasion and metastasis. Our previous studies utilizing a transgenic model deficient for 5’nucleotidase (CD73), an enzyme responsible for adenosine biosynthesis, demonstrated that adenosine is required to circumvent hypoxia-mediated disruption of cellular adhesiveness in the normal endometrium. In endometrial carcinoma (EC), CD73 is down-regulated in poorly-differentiated, invasive, and metastatic ECs, but is expressed and functional in well-differentiated and non-metastatic disease. Based on these findings, we hypothesized that the malignant progression of EC is dependant on the loss of adenosine-mediated regulation of intercellular adhesions. Modified and unmodified Boyden chambers were used to assess migration and invasion of endometrial adenocarcinoma cells HEC-1A and HEC-1B. Hypoxia (5% or 1.5% O2) significantly reduced HEC-1A and HEC-1B migration and invasion in vitro; this effect was abrogated by CD73 RNA interference and the CD73 enzymatic inhibitor, α, β- methylenediphosphate (AoPCP). The inhibitory effect of CD73 on EC cell migration and invasion was restored by the stable, receptor-targeting adenosine analog, 5’-N-ethylcarboxamido adenosine (NECA). Quantitative RT-PCR identified two adenosine receptors, A1R and A2BR, to be expressed in HEC-1A and HEC-1B. Inhibition of the A2BR by MRS1754 significantly increased HEC-1B migration and invasion, while A1R antagonism (DPCPX) had no effect. A2BR inhibition in HEC-1A monolayers also resulted in increased paracellular permeability to FITC-labeled dextrans. Moreover, A2BR antagonism lowered cellular levels of junctional adhesion proteins claudin-1 and claudin-2, and resulted in increased accumulation of β-catenin within the cytoplasm. Intracellular pools of β-catenin re-organized to the cell membrane with NECA application. In summary, we have shown that CD73-generated adenosine is necessary to maintain normal protective epithelial barrier function in the uterus. Our results demonstrate for the first time that inhibition of adenosine-mediated stabilization of intercellular adhesions promotes cancer cell invasion and metastasis in a hypoxic microenvironment. (NIH TL1RR024147 and NIH 1P50CA098258-01) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1538. doi:10.1158/1538-7445.AM2011-1538

Artemin Reduces Sensitivity to Doxorubicin and Paclitaxel in Endometrial Carcinoma Cells through Specific Regulation of CD24

We have previously reported that artemin (ARTN) stimulates the oncogenicity and invasiveness of endometrial carcinoma cells. Herein, we demonstrate that ARTN modulates the sensitivity of endometrial carcinoma cells to agents used to treat late-stage endometrial carcinoma. Forced expression of ARTN in endometrial carcinoma cells decreased sensitivity to doxorubicin and paclitaxel. Accordingly, depletion of ARTN by small interfering RNA or functional inhibition of ARTN with antibodies significantly increased sensitivity of endometrial carcinoma cells to doxorubicin and paclitaxel. Forced expression of ARTN in endometrial carcinoma cells abrogated doxorubicin-induced G2-M arrest and paclitaxel-induced apoptosis. ARTN increased CD24 expression in endometrial carcinoma cells by transcriptional up-regulation, and CD24 was partially correlated to ARTN expression in endometrial carcinoma. Forced expression of CD24 in endometrial carcinoma cells stimulated cell proliferation and oncogenicity, enhanced cell invasion, and decreased sensitivity to doxorubicin and paclitaxel. Depletion of CD24 in endometrial carcinoma cells abrogated ARTN-stimulated resistance to doxorubicin and paclitaxel. ARTN-stimulated resistance to doxorubicin and paclitaxel in endometrial carcinoma cells is therefore mediated by the specific regulation of CD24. Functional inhibition of ARTN may therefore be considered as an adjuvant therapeutic approach to improve the response of endometrial carcinoma to specific chemotherapeutic agents.

STAT3α Is Oncogenic for Endometrial Carcinoma Cells and Mediates the Oncogenic Effects of Autocrine Human Growth Hormone

We herein demonstrate an oncogenic role for signal transducer and activator of transcription (STAT)-3alpha (the full length STAT3 isoform), which also mediates autocrine human GH (hGH)-stimulated oncogenicity, in human endometrial carcinoma (EC) cells. Autocrine hGH stimulated Y705 phosphorylation of STAT3 and STAT3-mediated transcriptional activity in a SRC and Janus-2 Kinase dependent manner in human EC cell lines. Forced expression of a constitutively active variant of STAT3alpha increased proliferation, anchorage-independent, three-dimensional (3D) Matrigel, and xenograft growth and promoted epithelial-mesenchymal transition, migration, and invasion of EC cells. Conversely, the oncogenic capacity of EC cells was significantly impaired by treatment with JSI-124, an inhibitor of STAT3 phosphorylation and activity, small interfering RNA-mediated depletion of STAT3alpha, or a dominant-negative variant of STAT3alpha. Furthermore, the enhanced EC cell oncogenicity stimulated by autocrine hGH, was also abrogated by functional inhibition or small interfering RNA-mediated depletion of STAT3alpha. STAT3alpha may therefore be a common mediator of oncogenic signaling pathways stimulating progression of EC.

Artemin Stimulates Oncogenicity and Invasiveness of Human Endometrial Carcinoma Cells

Here, we provide evidence for a functional role of artemin (ARTN) in progression of endometrial carcinoma (EC). Increased ARTN protein expression was observed in EC compared with normal endometrial tissue, and ARTN protein expression in EC was significantly associated with higher tumor grade and invasiveness. Forced expression of ARTN in EC cells significantly increased total cell number as a result of enhanced cell cycle progression and cell survival. In addition, forced expression of ARTN significantly enhanced anchorage-independent growth and invasiveness of EC cells. Moreover, forced expression of ARTN increased tumor size in xenograft models and produced highly proliferative, poorly differentiated, and invasive tumors. The ARTN-stimulated increases in oncogenicity and invasion were mediated by increased expression and activity of AKT1. Small interfering RNA-mediated depletion or antibody inhibition of ARTN significantly reduced oncogenicity and invasion of EC cells. Thus, inhibition of ARTN may be considered as a potential therapeutic strategy to retard progression of EC.

Novel expression profiles and invasiveness-related biology function of DKK1 in endometrial carcinoma

DKK1 is a negative regulator in the Wnt signal transduction pathway. It can inhibit the pathway's activation. Previous studies in some malignant tumors revealed the possibility that DKK1 is involved in tumorigenesis inducing abnormalities of the Wnt signal pathway. In this study, we showed that in benign and malignant endometrium, DKK1 exhibited novel expression profiles and invasiveness-related biology function: DKK1 was expressed in both glandular epithelium and matrix of two kinds of endometrium tissues and mostly distributed in the cytoplasm and epicytes of endometrial carcinoma (EC) Ishikawa cell line. DKK1 expression level in EC was significantly lower than that in benign endometrium. The expression correlated well with histology and clinical stage of EC. Exogenous DKK1 suppressed invasiveness of EC cells. Taken together, DKK1 is involved in genesis and early phase of EC by suppressing the invasiveness via the Wnt signal pathway. It shows promise as a biomarker for screening the progression of EC.

Transforming Growth Factor-β3 Increases the Invasiveness of Endometrial Carcinoma Cells through Phosphatidylinositol 3-Kinase-dependent Up-regulation of X-linked Inhibitor of Apoptosis and Protein Kinase C-dependent Induction of Matrix Metalloproteinase-9

Tumor cells often acquire intrinsic resistance to the growth inhibitory and pro-apoptotic effects of transforming growth factor-beta (TGF-beta); moreover, TGF-beta can confer invasive properties to established tumor cells. In the present study, we show that TGF-beta isoforms (TGF-beta1, TGF-beta2, and TGF-beta3) trigger proper Smad signaling in human endometrial carcinoma cell lines and efficiently inhibit cellular proliferation. These cells, however, exhibit a high degree of resistance to TGF-beta pro-apoptotic effects; we found that this resistant phenotype would be acquired through up-regulation of X-linked inhibitor of apoptosis protein (XIAP) levels. In addition, using RNA interference and pharmacological inhibitors, we show that TGF-beta increases cellular invasiveness via two distinct signaling pathways in endometrial carcinoma cells: phosphatidylinositol 3-kinase/AKT-dependent up-regulation of XIAP and protein kinase C-dependent induction of matrix-metalloproteinase-9 (MMP-9) expression. Additionally, these findings were correlated with clinical observations showing abundant TGF-beta immunoreactivity in human endometrial carcinoma tumors in vivo, extending from the epithelial compartment to the stroma upon acquisition of an invasive phenotype (gradually from grades I to III). Collectively our results describe for the first time a role for TGF-beta3 in tumor invasiveness.