BACKGROUND: Although increasing abnormal expression of circular RNAs (circRNAs) has been revealed in various cancers, there were a small number of studies about circRNAs in gastric cancer (GC). Here, we explored the expression and function of a novel circRNA, circ_0049447, in GC. METHODS: A total of 80 GC tissues and non-tumorous tissues were collected from the First Affiliated Hospital of China Medical University. And all cells were cultured with 10% fetal bovine serum and incubated at 37°C and 5% CO2. The expression of circ_0049447 was quantified by real-time polymerase chain reaction. The biological function of circ_0049447 on proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) was evaluated by cell counting kit-8 (CCK-8), colony formation assay, transwell migration and invasion assay, and Western blotting. Luciferase report assay was used to verify the direct binding between circ_0049447 and predicted microRNA (miRNA). Furthermore, a xenograft mouse model was used to validate the function of circ_0049447 in vivo. RESULTS: We demonstrated that circ_0049447 was downregulated in GC (P < 0.001). The area under the receiver operating characteristic curve reached 0.838, while sensitivity was 82.3% and specificity was 77.2%. CCK-8 and colony formation assay showed that overexpression of circ_0049447 could inhibit the proliferation (P < 0.05). Transwell migration and invasion assay showed upregulated circ_0049447 could impede migration in GC cells (P < 0.05). In addition, overexpression of circ_0049447 could impede GC cell EMT. Upregulation of miR-324-5p in GC specimens and direct binding between miR-324-5p with circ_0049447 proven by luciferase reporter assay indicated that circ_0049447 may inhibit GC by sponging certain miRNA. CONCLUSION Circ_0049447 acts as a tumor suppressor in GC through reducing proliferation, migration, invasion, and EMT, and it is a promising biomarker for diagnosis.
Animals ; Cell Line, Tumor ; Cell Proliferation/genetics* ; China ; Epithelial-Mesenchymal Transition/genetics* ; Mice ; Stomach Neoplasms/genetics*

Metastasis is the main cause of cancer mortality. One of the initiating events of cancer metastasis of epithelial tumors is epithelial-to-mesenchymal transition (EMT), during which cells dedifferentiate from a relatively rigid cell structure/morphology to a flexible and changeable structure/morphology often associated with mesenchymal cells. The presence of EMT in human epithelial tumors is reflected by the increased expression of genes and levels of proteins that are preferentially present in mesenchymal cells. The combined presence of these genes forms the basis of mesenchymal gene signatures, which are the foundation for classifying a mesenchymal subtype of tumors. Indeed, tumor classification schemes that use clustering analysis of large genomic characterizations, like The Cancer Genome Atlas (TCGA), have defined mesenchymal subtype in a number of cancer types, such as high-grade serous ovarian cancer and glioblastoma. However, recent analyses have shown that gene expression-based classifications of mesenchymal subtypes often do not associate with poor survival. This "paradox" can be ameliorated using integrated analysis that combines multiple data types. We recently found that integrating mRNA and microRNA (miRNA) data revealed an integrated mesenchymal subtype that is consistently associated with poor survival in multiple cohorts of patients with serous ovarian cancer. This network consists of 8 major miRNAs and 214 mRNAs. Among the 8 miRNAs, 4 are known to be regulators of EMT. This review provides a summary of these 8 miRNAs, which were associated with the integrated mesenchymal subtype of serous ovarian cancer.
Cystadenocarcinoma, Serous ; genetics ; pathology ; Epithelial-Mesenchymal Transition ; Female ; Humans ; MicroRNAs ; physiology ; Ovarian Neoplasms ; genetics ; pathology

GATA transcription factor family members have been found to involve in the growth and differentiation of mammary gland. Among them GATA-3 is regarded as the most critical regulator involving the tumorigenesis of breast cancer (BC). Recently, trichorhinophalangeal syndrome-1 gene (TRPS-1), a new GATA family member, has been identified to be highly prevalent in breast cancer. Compared with ER-negative breast cancer, the expression of TRPS-1 is higher in ER-positive breast cancer and was significantly correlates with estrogen receptor, progesterone receptor, and GATA-3, indicating it may serve as a ductal epithelial cell-specific regulator in the differentiation of breast ductal epithelial cells. Studies have shown that miR221/222 is able to downregulate the expression of an epithelial cell marker E-cadherin by targeting TRPS-1, resulting in mammary epithelial cells transition to mesenchymal cell (EMT). In addition, it has been well accepted that, and the Science and Technology Bureau of Jiaxing (2012AY1071-2)TRPS-1 plays a role in the differentiation of several other cell types including kidney nephric mesenchymal cells, columnar chondrocytes, and osteoclasts, indicating that TRPS-1 involves in mesenchymal-to-epithelial cell transition (MET). In this article, we summarize the roles of GATA transcription factor TRPS-1 in ductal epithelial cells and the roles of its gene and protein expressions in predicting the prognosis of breast cancer.
Breast Neoplasms ; genetics ; pathology ; DNA-Binding Proteins ; genetics ; Epithelial-Mesenchymal Transition ; Female ; GATA3 Transcription Factor ; genetics ; Humans ; Transcription Factors ; genetics

Kidney is one of the most important organs of the body and the mammalian kidney development is essential for kidney unit formation. The key process of kidney development is metanephric development, where mesenchymal-epithelial transition (MET) plays a crucial role. Here we investigated the biological function of PPP3CA in metanephric mesenchyme (MM) cells. qRT-PCR and Western blotting were used to detect PPP3CA and MET makers expression in mK3, mK4 cells respectively at mRNA and protein level. Subsequently, PPP3CA was stably knocked down via lentivirus infection in mK4 cells. Flow cytometry, EdU/CCK-8 assay, wound healing assay were conducted to clarify the regulation of PPP3CA on cell apoptosis, proliferation and migration respectively. PPP3CA was expressed higher in epithelial-like mK4 cells than mesenchyme-like mK3 cells. Thus, PPP3CA was silenced in mK4 cells and PPP3CA deficiency promoted E-cadherin expression, cell apoptosis. Moreover, PPP3CA knock down attenuated cell proliferation and cell migration in mK4 cell. The underlying mechanism was associated with the dephosphorylation of PPP3CA on ERK1/2. Taken together, our results indicated that PPP3CA mediated MET process and cell behaviors of MM cells, providing new foundation for analyzing potential regulator in kidney development process.
Animals ; Apoptosis/genetics* ; Cell Line ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Epithelial-Mesenchymal Transition/genetics* ; Gene Silencing ; Mesenchymal Stem Cells/cytology* ; Mesoderm ; Mice

OBJECTIVETo examine the transfection of Homeobox A13 (HOXA13) on epithelial-mesenchymal transition (EMT) and the expression of bone morphogenetic protein-7 (BMP-7) induced by albumin-overload in human kidney tubular epithelial cells (HKCs).

METHODSThe cultured HKCs were treated with 20 mg/mL human serum albumin (HSA) for 48 hours. Protein expression of cytokeratin (CK), vimentin and HOXA13 in the HKCs was assessed by Western blot. Protein expression of CK, vimentin, and BMP-7 was also detected in HKCs transfected with lipofectamine contained HOXA13 DNA.

RESULTSHSA induced EMT in HKCs, presented by decreased CK expression (P<0.01) and increased vimentin expression (P<0.01). The up-regulated expression of HOXA13 transfected by lipofectamine inhibited the level of EMT induced by HSA in HKCs (P<0.05). The decreased rate of BMP-7 protein expression induced by HSA was inhibited by over-expressed HOXA13 in HKCs (P<0.05).

CONCLUSIONSTransfection of HOXA13 in HKCs could inhibit the degree of EMT induced by albumin-overload, possibly by increasing BMP-7 expression.

Bone Morphogenetic Protein 7 ; genetics ; Cells, Cultured ; Epithelial Cells ; metabolism ; Epithelial-Mesenchymal Transition ; Homeodomain Proteins ; physiology ; Humans ; Keratins ; genetics ; Kidney Tubules ; metabolism ; Transfection ; Vimentin ; genetics

Animals ; Epithelial Cells ; Epithelial-Mesenchymal Transition/genetics* ; MicroRNAs/genetics* ; Rats ; Rats, Inbred SHR ; Transforming Growth Factor beta/genetics* ; Transforming Growth Factor beta1/pharmacology*

OBJECTIVETo investigate the influence of silencing PAX2 gene in vivo on epithelial-mesenchymal transition (EMT) of renal tubular cells in rats with renal interstitial fibrosis.

METHODSA total of 64 Wistar rats were anaesthetized, and unilateral ureteral obstruction (UUO) was performed to establish a rat model of renal interstitial fibrosis. The 64 rats were randomly divided into negative control and PAX2 gene silencing groups (n=32 each). The rats in the control group were transfected with 200 μL NC-siRNA-in vivo jetPEI(TM) solution. Those in the PAX2 gene silencing group were transfected with 200 μL PAX2-siRNA-in vivo jetPEI(TM) solution. Each group was further divided into 4 subgroups based on the post-transfection time (3, 5, 7 and 14 days after transfection), with 8 rats in each subgroup. Renal tissue samples were harvested in each group. Real-time PCR and Western blot were used to measure the mRNA and protein expression of PAX2 in the renal cortex, as well as the mRNA and protein expression of E-cadherin and α-SMA.

RESULTSCompared with the control group, the PAX2 gene silencing group showed significantly lower mRNA and protein expression of PAX2 (P<0.05). In the two groups, the mRNA and protein expression levels of E-cadherin were gradually reduced over the time of obstruction, while those of α-SMA gradually increased. At 14 days after transfection, the PAX2 gene silencing group had significantly higher mRNA and protein expression of E-cadherin but lower mRNA and protein expression of α-SMA compared with the control group (P<0.05).

CONCLUSIONSPAX2 gene silencing can significantly inhibit the process of EMT of renal tubular cells in rats with advanced fibrosis, suggesting that PAX2 gene silencing may have a therapeutic effect on renal interstitial fibrosis.

Animals ; Epithelial-Mesenchymal Transition ; Fibrosis ; Gene Silencing ; Kidney ; pathology ; Male ; PAX2 Transcription Factor ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar

Globally, the incidence of colorectal carcinoma (CRC) ranks the third among all cancers. The incidence of CRC is continually increasing in China. Invasion and metastasis are the major causes of death. Metastasis is a complex multistep malignant process, including the detachment of tumor cells from the primary site, interaction of tumor cells with the surrounding extracellular matrix, entering into the circulation or lymph system, adhesion to the endothelial cells of vascular wall, migration of tumor cells into secondary sites, angiogenesis and formation of new metastases. This article reviews the recent research progress in aspects of the metastasis related genes, microRNAs, epithelial mesenchymal transition, tumor stem cells, and micro environment of colorectal cancer.
Colorectal Neoplasms ; pathology ; Epithelial-Mesenchymal Transition ; Humans ; MicroRNAs ; Neoplasm Invasiveness ; Neoplasm Metastasis ; genetics ; pathology ; Neoplastic Stem Cells ; Tumor Microenvironment

Cell fate conversion is considered as the changing of one type of cells to another type including somatic cell reprogramming (de-differentiation), differentiation, and trans-differentiation. Epithelial and mesenchymal cells are two major types of cells and the transitions between these two cell states as epithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) have been observed during multiple cell fate conversions including embryonic development, tumor progression and somatic cell reprogramming. In addition, MET and sequential EMT-MET during the generation of induced pluripotent stem cells (iPSC) from fibroblasts have been reported recently. Such observation is consistent with multiple rounds of sequential EMT-MET during embryonic development which could be considered as a reversed process of reprogramming at least partially. Therefore in current review, we briefly discussed the potential roles played by EMT, MET, or even sequential EMT-MET during different kinds of cell fate conversions. We also provided some preliminary hypotheses on the mechanisms that connect cell state transitions and cell fate conversions based on results collected from cell cycle, epigenetic regulation, and stemness acquisition.
Animals ; Cell Differentiation ; Cell Lineage ; Cellular Reprogramming ; Epigenesis, Genetic ; genetics ; Epithelial-Mesenchymal Transition ; Humans ; Induced Pluripotent Stem Cells ; cytology

BACKGROUND: Epithelial to mesenchymal transition (EMT) is strongly linked with tumor invasion and metastasis, which performs a vital role in carcinogenesis and cancer progression. Emerging evidence suggests that microRNAs (miRNAs) expression are closely associated to EMT by regulating targeted genes. MiR542 has been found to be involved in the EMT program and bound up with various cancers. However, the functions of miR542 and its underlying mechanism in glioblastoma multiforme (GBM) remain largely unknown. In the current study, we investigated the effect of astrocyte elevated gene-1 (AEG-1) on U251 cells aggressiveness, proliferation, apoptosis, and cell cycle. METHODS: The screening of targeted miRNAs was performed, as well as the functional roles and mechanisms of miR542 were explored. RESULTS: MiR542 was selected as the target because of the most significantly differential expression and this high level of expression negatively correlated with cell migration and proliferation, which suggested that miR542 could be a novel tumor suppressor. Moreover, we confirmed that AEG-1 was a direct targeted gene of miR542 by luciferase activity assay, reverse transcription-polymerase chain reaction, and immunoblotting analysis. Furthermore, miR542 suppressed the expression of AEG-1, which upgraded the level of E-cadherin and degraded Vimentin expression contributing to retraining EMT. CONCLUSION The in vitro findings demonstrated that miR542 inhibited the migration and proliferation of U251 cells and suppressed EMT through targeting AEG-1, indicating that miR542 may be a potential anti-cancer target for GBM.
Astrocytes ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Epithelial-Mesenchymal Transition/genetics* ; Gene Expression Regulation, Neoplastic ; Glioblastoma/genetics* ; Humans ; MicroRNAs/genetics* ; Neoplasm Invasiveness/genetics*