Transition In Ovarian Cancer Cells Research Articles

Retracted] ATP‑binding cassette transporter A7 accelerates epithelial‑to‑mesenchymal transition in ovarian cancer cells by upregulating the transforming growth factor‑β signaling pathway.

[This retracts the article DOI: 10.3892/ol.2018.9366.].

Methyl vanillate for inhibiting the proliferation, migration, and epithelial-mesenchymal transition of ovarian cancer cells via the ZEB2/Snail signaling pathway.

Globally, ovarian cancer is the leading cause of female reproductive-related death, with a 5-year survival rate below 50%. Conventional therapies, such as cancer cell reduction and paclitaxel chemotherapy, have strong toxicity and are prone to drug resistance. Thus, the development of alternatives for the treatment of ovarian cancer is urgently needed. Methyl vanillate is a principal component of Hovenia dulcis Thunberg. It is known that several cancer cells are inhibited by methyl vanillate; however, whether methyl vanillate can inhibit the proliferation and migration of ovarian cancer cells still needs to be further studied. In this study, cell counting kit 8 (CCK8) was used to examine the effects of methyl vanillic acid on the proliferation of SKOV3 cell lines and human ovarian surface epithelial cell (HOSEpiC) lines. Wound healing and transwell assays were used to determine the effect of methyl vanillate on cell migration. The expression of epithelial-mesenchymal transition (EMT) marker proteins (E-cadherin and vimentin), transcription factors (Snail and ZEB2), and skeletal proteins (F-actin) were evaluated with Western blotting. F-actin was detected by immunofluorescence assay. The proliferation and migration of SKOV3 cells were dose-dependently inhibited by methyl vanillate, but HOSEpiC cells were not inhibited by low concentrations of methyl vanillate. Western blotting analyses revealed a significant decrease in the expression of vimentin and a significant increase in the expression of E-cadherin in SKOV3 cells treated with methyl vanillate. This finding indicated that EMT inhibition was induced by the vanillate. Furthermore, methyl vanillate inhibited the expression of transcription factors (Snail and ZEB2) in SKOV3 cells as well as cytoskeletal F-actin assembly. Methyl vanillate plays an important role in inhibiting EMT and cell proliferation and the migration of ovarian cancer, likely via the inhibition of the ZEB2/Snail signaling pathway. Consequently, methyl vanillate may be a promising therapeutic drug for ovarian cancer.

Effect of WWOX on epithelial-mesenchymal transition in ovarian cancer cells in vivo, and its association with Elf5/Snail-1 signal pathway

Purpose: To investigate how WW domain-containing oxidoreductase (WWOX) gene affects epithelial-mesenchymal transition (EMT) of ovarian cancer (OC) cells, and the implication of Elf5/Snail-1 pathway in the process.
 Methods: This study employed female BALB/c nude mice aged 6 weeks. The expression levels of E-cadherin, β-Catenin, N-cadherin, Vimentin, Snail1 and Elf5 were assayed using qRT-PCR. The protein levels of WW1, WW2, E-cad, β-Cat, N-cad, vimentin, Snail-1 and Elf5 were determined using western blotting (WB). Invasion changes in cells in each group were analyzed by Transwell invasion test while WWOX and Elf5 were evaluated by GST pull-down test; furthermore, WWOX and ELF5 were evaluated by co-immunoprecipitation (COIP).
 Results: Relative to control group, tumor volume and weight of WWOX high-expression mice were significantly decreased, while those of WWOX low-expression group were increased (p < 0.05). The levels of E-cad, Elf5 and β-catenin increased, but those of N-cad, Snail-1 and vimentin decreased in WWOX high expression group. In the WWOX low-expression group, the levels of E-cad, Elf5 and β-cat were down-regulated, while those of N-cad, Snail-1 and vimentin were up-regulated (p < 0.05). The expression of E-cad, Elf5 and β-cat declined; on the other hand, those of N-Cad, Snail-1 and vimentin were elevated after mutation of WW1 domain in WWOX gene (p < 0.05).
 Conclusion: Based on the in vivo results, the role of WWOX/Elf5/Snail1 signal route in the epithelial-mesenchymal transition of ovarian cancer, and its related mechanisms have been clarified. This provides a new target for gene therapy of ovarian cancer.

Wnt5A and TGFβ1 Converges through YAP1 Activity and Integrin Alpha v Up-Regulation Promoting Epithelial to Mesenchymal Transition in Ovarian Cancer Cells and Mesothelial Cell Activation.

In this paper, we investigate whether Wnt5A is associated with the TGF-β1/Smad2/3 and Hippo-YAP1/TAZ-TEAD pathways, implicated in epithelial to mesenchymal transition (EMT) in epithelial ovarian cancer. We used 3D and 2D cultures of human epithelial ovarian cancer cell lines SKOV-3, OVCAR-3, CAOV-4, and different subtypes of human serous ovarian cancer compared to normal ovary specimens. Wnt5A showed a positive correlation with TAZ and TGFβ1 in high- and low-grade serous ovarian cancer specimens compared to borderline serous and normal ovaries. Silencing Wnt5A by siRNAs significantly decreased Smad2/3 activation and YAP1 expression and nuclear shuttling in ovarian cancer (OvCa) cells. Furthermore, Wnt5A was required for TGFβ1-induced cell migration and invasion. In addition, inhibition of YAP1 transcriptional activity by Verteporfin (VP) altered OvCa cell migration and invasion through decreased Wnt5A expression and inhibition of Smad2/3 activation, which was reverted in the presence of exogenous Wnt5A. We found that the activation of TGFβ1 and YAP1 nuclear shuttling was promoted by Wnt5A-induced integrin alpha v. Lastly, Wnt5A was implicated in activating human primary omental mesothelial cells and subsequent invasion of ovarian cancer cells. Together, we propose that Wnt5A could be a critical mediator of EMT-associated pathways.

MicroRNA-30 inhibits the growth of human ovarian cancer cells by suppressing RAB32 expression.

IntroductionMicroRNAs (miRs) exhibit the potential to act as therapeutic targets for the management of human cancers including ovarian cancer. The role of microRNA-30 (miR-30) via modulation of RAB32 expression has not been studied in ovarian cancer. Consistently, the present study was designed to characterize the molecular role of miR-30/RAB32 axis in human ovarian cancer.MethodsCell viability was determined by MTT assay. Expression analysis was carried out by qRT-PCR. Dual luciferase assay was used to confirm the interaction between miR-30 and RAB32. Scratch-heal and transwell chamber assays were used to monitor the cell migration and invasion. Western blotting and immunofluorescence assays were used to determine the protein expression.ResultsThe results revealed significant (p < 0.05) downregulation of miR-30 in human ovarian cancer cell lines. Overexpression of miR-30 in ovarian SK-OV-3 and A2780 cancer cells significantly (p < 0.05) inhibited their proliferation. Besides, ovarian cancer cells overexpressing miR-30 showed significantly (p < 0.05) lower migration and invasion. The miR-30 upregulation also altered the expression pattern of marker proteins of epithelial–mesenchymal transition in ovarian cancer cells. In silico analysis predicted RAB32 as the molecular target of miR-30 at post-transcriptional level. The silencing of RAB32 mimicked the tumor-suppressive effects of miR-30 overexpression in ovarian cancer cells. Nonetheless, overexpression of RAB32 could prevent the tumor-suppressive effects of miR-30 on SK-OV-3 and A2780 cancer cells.ConclusionTaken together, the results suggest the tumor-suppressive role of miR-30 and point towards the therapeutic utility of miR-30/RAB32 molecular axis in the management of ovarian cancer

A transcription factor that promotes proliferation, migration, invasion, and epithelial\u2013mesenchymal transition of ovarian cancer cells and its possible mechanisms

BackgroundOvarian cancer is one of the most common gynecological malignancies with the high morbidity and mortality. This study was aimed to explore the role of non-structure maintenance of chromosomes condensin I complex subunit H (NCAPH) in the progression of ovarian cancer (OC) and the transcription regulatory effects of GATA binding protein 3 (GATA3) on this gene.MethodsFirstly, NCAPH and GATA3 expression in OC tissues and several human OC cell lines was, respectively, evaluated by TNMplot database and Western blot analysis. Then, NCAPH was silenced to assess the proliferation, migration, and invasion of OC cells in turn using CCK-8, wound healing, and transwell assays. Western blotting was used to determine the expression of epithelial--mesenchymal transition (EMT)-related proteins and PI3K/PDK1/AKT signaling proteins. The potential binding sites of GATA3 on NCAPH promoter were predicated using JASPAR database, which were verified by luciferase reporter assay and chromosomal immunoprecipitation. Subsequently, GATA3 was overexpressed to examine the biological functions of OC cells with NCAPH silencing.ResultsNCAPH and GATA3 expression was significantly upregulated in OC tissues and cell lines. NCAPH loss-of-function notably inhibited the proliferation, migration, invasion, and EMT of OC cells. Moreover, the expression of p-PI3K, PDK1, and p-AKT was downregulated after NCAPH knockdown. Furthermore, GATA3 was confirmed to bind to NCAPH promoter. GATA3 overexpression alleviated the inhibitory effects of NCAPH silencing on the proliferation, migration, invasion, EMT, and expression of proteins in PI3K/PDK1/AKT pathway of OC cells.ConclusionTo sum up, NCAPH expression transcriptional activation by GATA3 accelerates the progression of OC via upregulating PI3K/PDK1/AKT pathway.

Overexpression of Long Noncoding RNA H19 Downregulates miR-140-5p and Activates PI3K/AKT Signaling Pathway to Promote Invasion, Migration and Epithelial-Mesenchymal Transition of Ovarian Cancer Cells.

Objective The abnormal expression of LncRNA H19 and miR-140-5p has been linked to ovarian cancer (OC). Whether H19 directly regulates miR-140-5p in ovarian cancer cells has been unclear. In this study, we deeply explored the relationship between H19 and miR-140-5p in ovarian cancer and the mechanism of action in regulating OC progression. Methods A total of 66 patients with OC admitted to the hospital from June 2017 to June 2019 were selected as the research group (RG), and meanwhile, 60 cases of healthy subjects were selected as the control group (CG). In addition, OC cells and normal ovarian epithelial cells were used to detect H19 and miR-140-5p expression levels and to analyze the effect of H19 on OC cells. The activation of the PI3K/AKT pathway and downstream proteins were analyzed by western blot. Results H19 was highly expressed while miR-140-5p was lowly expressed in OC patients and cell lines (P < 0.050). The proliferation, invasion, migration ability, and epithelial-mesenchymal transition (EMT) of OC cells were reduced after inhibiting H19 expression, and the apoptosis rate was increased. Transfection of cells with miR-140-5p mimics brought opposite effects. Online prediction and dual-luciferase reporter (DLR) confirmed that H19 directly binds miR-140-5p. Western blot assay indicated overexpression activated the PI3K/AKT signaling pathway in OC cells. Moreover, overexpression promoted tumor growth in nude mice and was suppressed by PI3K inhibitor. Conclusion LncRNA H19 downregulation of miR-140-5p to activate the PI3K/AKT signaling pathway and promote the proliferation, invasion, migration and EMT of OC.

Exosomes in ovarian cancer ascites promote epithelial\u2013mesenchymal transition of ovarian cancer cells by delivery of miR-6780b-5p

The poor prognosis of ovarian cancer is mainly due to metastasis, and the specific mechanism underlying ovarian cancer metastasis is not clear. Ascites-derived exosomes (ADEs) play an important role in the progression of ovarian cancer, but the mechanism is unknown. Here, we found that ADEs promoted ovarian cancer metastasis not only in vitro but also in vivo. This promotive function was based on epithelial–mesenchymal transition (EMT) of ovarian cancer cells. Bioinformatics analysis of RNA sequencing microarray data indicated that miR-6780b-5p may be the key microRNA (miRNA) in ADEs that facilitates cancer metastasis. Moreover, the expression of exosomal miR-6780b-5p correlated with tumor metastasis in ovarian cancer patients. miR-6780b-5p overexpression promoted and miR-6780b-5p downregulation suppressed EMT of ovarian cancer cells. These results suggest that ADEs transfer miR-6780b-5p to ovarian cancer cells, promoting EMT and finally facilitating ovarian cancer metastasis.

Correction to: Interaction between LncRNA-ROR and miR-145 contributes to epithelial-mesenchymal transition of ovarian cancer cells

Correction to: Interaction between LncRNA-ROR and miR-145 contributes to epithelial-mesenchymal transition of ovarian cancer cells

Involvement of Wnt/β-catenin pathway in the inhibition of invasion and epithelial-mesenchymal transition in ovarian cancer cells

Purpose: To investigate the effects of zerumbone on cell invasion, epithelial-mesenchymal transition (EMT) and the potential signaling pathway involved in ovarian cancer cells.Methods: Caov-3 cell proliferation was assessed using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-diphenytetrazoliumromide (MTT) assay. Wound healing assay was used to determine Caov-3 cell migration while cell invasion was evaluated using Transwell assay. Protein expression was determinedby western blot.Results: Cell viability was reduced by 5, 10, 20, and 50 μM zerumbone (p &lt; 0.05) in a concentrationdependent manner while cell migration and invasion were inhibited by 10 and 20 μM zerumbone (p &lt; 0.05). Protein expression levels of E-cadherin and cytoplasm β-catenin were upregulated by zerumbone (p &lt; 0.05) in a concentration-dependent manner. On the other hand, protein expression levels of Ncadherin, vimentin, ZEB1, nuclear β-catenin, and c-Myc were suppressed by zerumbone (p &lt; 0.05) also in a concentration-dependent manner.Conclusion: The results demonstrate that zerumbone inhibits cell proliferation, migration and invasion, but represses the EMT process via inactivation of Wnt/β-catenin signaling pathway.&#x0D; Keywords: Zerumbone, Ovarian cancer, Wnt/β-catenin pathway, Epithelial-mesenchymal transition

Effects of activating GABAB1 receptor on proliferation, migration, invasion and epithelial-mesenchymal transition of ovarian cancer cells

ObjectiveThis study aimed to explore the effects of activating GABAB1 receptor by baclofen on proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of ovarian cancer cells.ResultsOne hundred μmol/L, 200 μmol/L and 300 μmol/L were selected as low, medium and high baclofen concentrations respectively. Cells were divided into four groups: Control, 100 μmol/L, 200 μmol/L and 300 μmol/L. Compared with the control group, the viability, colony formation, migration and invasion of SKOV3 cells were inhibited, and the apoptosis of SKOV3 cells were enhanced significantly at 200 μmol/L and 300 μmol/L baclofen. Moreover, they changed significantly with the increase of baclofen concentration. Compared with the control group, the expression of E-cadherin and GABAB1 increased and the N-cadherin expression decreased significantly in 200 μmol/L and 300 μmol/L groups. Higher concentration of baclofen induced higher expression of E-cadherin and lower expression of N-cadherin.ConclusionBaclofen inhibited the proliferation, cloning, migration, invasion and EMT of ovarian cancer cells by activating GABAB1 receptor. These results might contribute a lot to clarify the role and possible mechanism of GABAB1 receptor in ovarian cancer.

Abstract 122: Targeting forward and reverse EphB4/EFNB2 signaling by a peptide with dual functions

Although chloroquine administration in vivo following haemorrhage in mice decreases tumour necrosis factor-alpha (TNF-alpha) release by macrophage (M phi), the mechanism remains unknown. To study this, peritoneal M phi (pM phi) from unmanipulated, sham-operated and post-haemorrhage mice were isolated, treated with 0.13 mg/ml chloroquine for 2 hr, and then stimulated with lipopolysaccharide (LPS) for 48 hr. Pretreatment of pM phi from various groups of mice with chloroquine resulted in 75-90% inhibition of TNF-alpha release, determined by bioassay. Total RNA was isolated from pM phi and murine M phi-derived cell lines (P388D1 and RAW 264.7), stimulated with LPS for 0.5 or 1 hr, respectively, and Northern blot analysis for TNF-alpha mRNA performed. Chloroquine inhibited TNF-alpha mRNA expression without interfering with mRNA stability, suggesting that this agent reduces M phi TNF-alpha release by disrupting TNF-alpha gene transcription.

Abstract B59: Rac1 overexpression promotes epithelial-to-mesenchymal transition in ovarian cancer cells

Abstract The small GTPase Rac1 (Ras-related C3 botulinum toxin substrate 1) is commonly overexpressed in cancer and high Rac1 levels are associated with poor patient outcomes in ovarian cancer. Rac1 drives multiple hallmarks of cancer such as proliferation, quiescence, epithelial-to-mesenchymal transition (EMT), and transcriptional programs relevant to tumor development, progression, and chemoresistance. EMT promotes metastatic dissemination, chemoresistance, and cancer stem cell properties. We find that modest overexpression of Rac1 in ovarian tumor cells causes morphologic changes consistent with EMT. Elevated Rac1 (4- fold) expression decreases colony number and increases colony area when compared to vector control cells. In addition, cell invasion through an artificial basement membrane is increased by 10-fold in cells overexpressing Rac1. An increase in mesenchymal markers (e.g., N-cadherin) and decrease in epithelial markers (e.g., E-cadherin) was observed as a consequence of Rac1 expression. Rac1 overexpression was associated with selective upregulation of Slug/Snai2 (8-fold) and Zeb2 (100-fold) mRNA levels with little impact on Snai1, Twist, or Zeb1. Slug/Snai2 expression is reportedly induced by oxidative stress and treatment of six ovarian tumor cell lines with tert-butyl hydroperoxide (TBHP) to generate oxidative stress increased the expression Slug/Snai2, Snai1, and heme oxygenase-1, an indicator of oxidative stress response. This finding confirms that elevated oxidative stress regulates certain EMT transcription factors in various ovarian cancer cells. Rac1 is an essential factor for activation of NADPH oxidases 1, 2, and 3 and generation of reactive oxygen species (ROS). Basal level of ROS was elevated in cells overexpressing Rac1 compared to vector control cells as detected by the fluorescent probe Dihydroethidium (DHE). Similarly, elevated Rac1 increased expression of the oxidative stress response genes heme oxygenase-1 (17-fold) and superoxide dismutase-1 (12-fold), further supporting that Rac1 stimulated ROS signaling in these cells. We further tested the impact of Rac1 inhibition in vivo using R-ketorolac. Analysis of tumor tissue from mice showed decreased expression of heme-oxygenase-1 and Slug/Snai2 in mice treated with R-ketorolac compared to placebo controls. R-ketorolac also decreased invasive implantation and expansion of ovarian cancer xenografts. Taken together, these findings illustrate the functional impact of Rac1 overexpression in ovarian cancer cells and suggest that Rac1 may be a viable target for further drug development to attenuate EMT in ovarian tumors. Citation Format: Martha M. Grimes, Dayna R. Dominquez, Michaela L. Granados, Alejandra Rosales, Melanie Rivera, Angela Wandinger-Ness, Laurie G. Hudson. Rac1 overexpression promotes epithelial-to-mesenchymal transition in ovarian cancer cells [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr B59.

Targeting Forward and Reverse EphB4/EFNB2 Signaling by a Peptide with Dual Functions

The tyrosine kinase receptor EphB4 is frequently overexpressed in ovarian and other solid tumors and is involved in interactions between tumor cells and the tumor microenvironment, contributing to metastasis. Trans-interaction between EphB4 and its membrane-bound ligand ephrin B2 (EFNB2) mediates bi-directional signaling: forward EFNB2-to-EphB4 signaling suppresses tumor cell proliferation, while reverse EphB4-to-EFNB2 signaling stimulates the invasive and angiogenic properties of endothelial cells. Currently, no small molecule–based, dual-function, EphB4-binding peptides are available. Here, we report our discovery of a bi-directional ephrin agonist peptide, BIDEN-AP which, when selectively internalized via receptor-mediated endocytosis, suppressed invasion and epithelial-mesenchymal transition of ovarian cancer cells. BIDEN-AP also inhibited endothelial migration and tube formation. In vivo, BIDEN-AP and its nanoconjugate CCPM-BIDEN-AP significantly reduced growth of orthotopic ovarian tumors, with CCPM-BIDEN-AP displaying greater antitumor potency than BIDEN-AP. Both BIDEN-AP and CCPM-BIDEN-AP compromised angiogenesis by downregulating epithelial-mesenchymal transition and angiogenic pathways. Thus, we report a novel EphB4-based therapeutic approach against ovarian cancer.

SERPIND1 Affects the Malignant Biological Behavior of Epithelial Ovarian Cancer via the PI3K/AKT Pathway: A Mechanistic Study.

Serpin family D member 1 (SERPIND1) belongs to the serine protease inhibitor family. Its role in cancers has gradually attracted interest from researchers in recent years. However, the role of SERPIND1 in the development of epithelial ovarian cancer remains poorly understood. This studied aimed to investigate the expression and clinical significance of SERPIND1 in epithelial ovarian cancer, as well as its effect on the malignant biological behavior of ovarian cancer cells and the related regulatory mechanisms. We found that SERPIND1 expression was significantly elevated in epithelial ovarian cancer. Patients with higher expression of SERPIND1 in ovarian cancer tissues had poor prognoses. SERPIND1 promoted the proliferation, migration, invasion, G1-to-S phase transition, and epithelial–mesenchymal transition of ovarian cancer cells and inhibited their apoptosis by promoting phosphorylation in the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway. Meanwhile, the inhibition of SERPIND1 expression in ovarian cancer cells resulted in opposite effects. The addition of the PI3K/AKT pathway inhibitor LY294002 to SERPIND1-overexpressing cells could reverse the promoting effect of SERPIND1 on the malignant biological behavior of ovarian cancer cells. Further, nuclear factor kappa B subunit 1, a transcription factor could bind to the promoter region of SERPIND1 and regulate SERPIND1 expression. In conclusion, our results indicated that SERPIND1 could be an effective marker for assessing the prognosis of ovarian cancer. By elucidating its mechanism underlying the promotion of malignant biological behavior of ovarian cancer by SERPIND1, we demonstrated that SERPIND1 could potentially serve as a novel drug target.

MiR-9 accelerates epithelial-mesenchymal transition of ovarian cancer cells via inhibiting e-cadherin.

To investigate the influence of micro-ribonucleic acid (miR)-9 on epithelial-mesenchymal transition (EMT) of ovarian cancer cells by targeted inhibition on E-cadherin (CDH1). The human ovarian cancer cells were cultured and miR-9 was repressed by inhibitors and overexpressed by miRNA mimics. The expression of EMT-related proteins was measured via Western blotting (WB). The action target of miR-9 was determined through the dual-luciferase reporter gene assay. The changes in protein levels were detected using WB. The expression of miR-9 was markedly up-regulated in ovarian cancer tissues, that is, the expression level of serum miR-9 in ovarian cancer patients was higher than that in control group. After the inhibition of miR-9, the expression level of epithelial indicator CDH1 was increased, while that of interstitial indicator Vimentin was decreased. MiR-9 contained a complementary site in the 3'-untranslated region (UTR) of CDH1 messenger RNA (mRNA) and the mRNA and protein expressions of CDH1 in the cells were down-regulated obviously by miR-9 overexpression. MiR-9 promotes the EMT of ovarian cancer cells through the targeted inhibition on CDH1.

LncRNA MEG3 modified epithelial-mesenchymal transition of ovarian cancer cells by sponging miR-219a-5p and regulating EGFR.

This study was aimed to verify whether there existed any associations between long noncoding RNA MEG3/miR-219a-5p/EGFR axis and the development of ovarian cancer (OC). As a whole, we gathered 317 pairs of OC tissues and surgical marginal normal tissues and simultaneously acquired four OC cell lines (ie, A2780, Caov-3, OVCAR-3, and SKOV-3) and human normal ovarian surface epithelial cell line. Moreover, pcDNA3.1-MEG3, si-MEG3, miR-219a-5p mimic, miR-219a-5p inhibitor, pcDNA3.1-EGFR, and si-EGFR were, respectively, transfected into the OC cells, and their impacts on viability, proliferation, apoptosis, invasion, and migration of OC cells were assessed via conduction of MTT assay, colony formation assay, flow cytometry assay, transwell assay, and scratch assay. Ultimately, dual-luciferase reporter gene assay was performed to testify the targeted relationships among maternally expressed gene 3 (MEG3), miR-219a-5p, and estimated glomerular filtration rate (EGFR). It was indicated that underexpressed MEG3 and miR-219a-5p were significantly associated with unfavorable prognosis of patients with OC when compared with overexpressed MEG3 and miR-219a-5p (P < .05). In addition, the OC cells transfected with si-MEG3 or miR-219a-5p inhibitor exhibited stronger viability, proliferation, invasion, and migration than untreated cells (P < .05). Correspondingly, the apoptotic percentage of OC cells was reduced observably under treatments of si-MEG3 and miR-219a-5p inhibitor (P < .05). Moreover, MEG3 exerted modulatory effects on the expression of miR-219a-5p (P < .05), and there was a sponging relationship between them (P < .05). Finally, EGFR expression was modified by both MEG3 and miR-219a-5p significantly (P < .05), and raising EGFR expression could changeover the impacts of MEG3 and miR-219a-5p on the above-mentioned activity of OC cells (P < .05). Conclusively, MEG3 could serve as a promising biomarker for diagnosis and treatment of OC, considering its involvement with OC etiology via regulation of miR-219a-5p/EGFR axis.

Sequence diverse miRNAs converge to induce mesenchymal-to-epithelial transition in ovarian cancer cells through direct and indirect regulatory controls.

Epithelial-to-mesenchymal transition (EMT) has been shown to be similarly regulated by multiple miRNAs, some displaying little or no sequence identity. While alternate models have been proposed to explain the functional convergence of sequence divergent miRNAs, little experimental evidence exists to elucidate the underlying mechanisms involved. Representative members of the miR-200 family of miRNAs and the sequence divergent miR-205 miRNA were independently over expressed in mesenchymal-like ovarian cancer (OC) cells resulting in mesenchymal-to-epithelial transition (MET). The miR-205 and the miR-200 family of miRNAs were found to coordinately induce MET in mesenchymal-like OC cells by affecting both direct and indirect changes in the expression of genes previously associated with EMT/MET. Only two direct targets of these miRNAs (ZEB 1 and WNT5A) are commonly down regulated in response to over-expression of miR-205 and/or the miR-200 family of miRNAs. Down-regulation of these genes, alone or in combination, only partially recapitulates the changes induced by the miRNAs indicating an additional contribution of indirect changes regulated by the miRNAs. Combined gene expression analyses and phylogenetic comparisons suggest an evolutionarily more recent involvement of miR-205 in the EMT/MET process.

Platelets promote invasion and induce epithelial to mesenchymal transition in ovarian cancer cells by TGF-β signaling pathway

ObjectiveTo test whether platelets could increase invasion potential and initiate EMT in ovarian cancer cells via a TGF-β signaling pathway. MethodsBlood samples were collected in 69 patients with ovarian cancer, 16 patients with benign ovarian tumor and 64 healthy donors. SK-OV-3 and OVCAR-3 ovarian cancer cells were treated with platelets. Transwell assays were used to analyze the invasive capacity, and EMT was assessed by microarray analysis, quantitative real-time PCR (qPCR) and Western blotting. Activation of TGF-β pathway was examined by ELISA and Western blotting. TGF-β type I receptor (TβR I) inhibitor A83-01 was used to confirm the role of TGF-β pathway in vitro and in vivo. ResultsClinical data showed ovarian cancer patients with elevated platelet counts had a higher incidence of advanced stages. Treatment with platelets increased the invasive properties of both cell lines. Mesenchymal markers (snail family transcriptional repressor-1, vimentin, neural cadherin, fibronectin-1 and matrix metalloproteinase-2) were up-regulated in platelet-treated cells, while the epithelial marker (epithelial cadherin) was down-regulated. Higher TGF-β level was observed in patients with elevated platelet counts when compared to the subjects. Higher levels of TGF-β were also found in culture medium treated with platelets, and cells treated with platelets also showed increased phosphorylation of Smad2. TβR I inhibitor A83–01 reversed the EMT-like alterations and inhibited platelet-induced invasion in vitro and in vivo. ConclusionPlatelet increased invasion potential and induced EMT in ovarian cancer cells in a TGF-β dependent pathway. Platelet-derived TGF-β may be useful as a new target treatment for ovarian cancer.

HOXD-AS1 promotes the epithelial to mesenchymal transition of ovarian cancer cells by regulating miR-186-5p and PIK3R3

BackgroundEpithelial ovarian cancer (EOC) is one of the most malignant gynecological tumors worldwide. Deregulation of long non-coding RNAs (lncRNAs) has been implicated in various oncogenic processes in multiple cancers. In this study, we aim to identify and characterize clinically relevant lncRNA deregulation in EOC.MethodsLncRNAs, mRNAs and miRNAs were profiled using expression microarrays and validated using reverse transcription quantitative PCR in EOC cells and tissues. siRNAs targeting either HOXD-AS1 or PIK3R3 together with miR-186-5p inhibitors were used to modulate endogenous target expression in EOC cell lines in vitro. In vitro wound healing assay, trans-well assay, Western-blot assay,and Dual-luciferase reporter assay were used to explore the biological roles and molecular function underlying HOXD-AS1 in the EOC cells. Progression-free survival (PFS) and overall survival (OS) were statistically analyzed by Kaplan-Meier method test.ResultsHOXD-AS1 was found to be significantly over-expressed in EOC tumors. High HOXD-AS1 expression significantly correlated with poorer PFS and OS of EOC patients. Multivariate Cox proportional hazards modeling indicated that HOXD-AS1 was an independent risk predictor of EOC patients (HR = 1.92, p = 0.004). SiRNA inhibition of HOXD-AS1 reduced cell migration, invasion, and epithelial-mesenchymal transition (EMT) in EOC cells in vitro by preventing HOXD-AS1 directly binding to miR-186-5p, and resulting in down-regulating of PIK3R3. The novel HOXD-AS1/miR-186-5p/PIK3R3 pathway was clinically relevant as we observed a significantly inverse correlation between HOXD-AS1/miR-186-5p and between miR-186-5p/PIK3R3 in an independent cohort of 200 EOC tissues.ConclusionsHOXD-AS1/miR-186-5p/PIK3R3 is a novel pathway to promote cell migration, invasion, and EMT in EOC.