Colorectal cancer is highly metastatic even when the tumors are small. To disseminate, cells use a complex and multistage process known as the epithelial-mesenchymal transition, in which epithelial phenotype is transformed into mesenchymal phenotype. The objective of this study is to describe the epithelial-mesenchymal transition in terms of gene expression profile and somatic alterations in samples of colorectal cancer with or without peritoneal carcinomatosis. We analyzed samples taken from 38 patients with colorectal cancer (stages II-IV) and samples from 20 patients with colorectal cancer complicated by peritoneal carcinomatosis. The expression of ZEB1, ZEB2, CDH1, VIM, and SNAI1 was analyzed by real-time PCR. KRAS/BRAF mutations were mapped using sequencing. Microsatellite instability was evaluated by fragment analysis. Epithelial-mesenchymal transition was detected in 6 out of 38 samples of colorectal cancer (stages II-IV), 7 out of 20 tumors from patients with peritoneal carcinomatosis, and 19 out of 20 samples taken from carcinomatous nodules. Tumors of the mesenchymal subtype displayed high frequency of somatic mutations, microsatellite stability, and low degree of differentiation. The identification of epithelial-mesenchymal transition may be used as a marker of high metastatic potential, which is particularly relevant at early stages of tumor growth.

OBJECTIVE

To explore the molecular mechanisms in lens development and the pathogenesis of Peters anomaly in Smad4 defective mice.

METHODS

Le-Cre transgenic mouse line was employed to inactivate Smad4 in the surface ectoderm selectively. Pathological techniques were used to reveal the morphological changes of the anterior segment in Smad4 defective eye. Immunohistochemical staining was employed to observe the expression of E-cadherin, N-cadherin and α-SMA in anterior segment of Smad4 defective mice and control mice at embryonic (E) day 16.5. Real-time quantitative polymerase chain reaction (qPCR) was performed to detect the expression of Snail, Zeb1, Zeb2 and Twist2 in lens of Smad4 defective mice and control mice at E16.5. Statistical evaluations were performed using the unpaired Student's t-test (two-tailed) by SPSS 11.0 software.

RESULTS

Conditional deletion of Smad4 on eye surface ectoderm resulted in corneal dysplasia, iridocorneal angle closure, corneolenticular adhesions and cataract resembling Peters anomaly. Loss of Smad4 function inhibited E-cadherin expression in the lens epithelium cells and corneal epithelium cells in Smad4 defective eye. Expression of N-cadherin was up-regulated in corneal epithelium and corneal stroma. Both E-cadherin and N-cadherin were down-regulated at the future trabecular meshwork region in mutant eye. The qPCR results showed that the expression of Twist2 was increased significantly in the mutant lens (P<0.01).

CONCLUSIONS

Smad4 is essential to eye development and likely a candidate pathogenic gene to Peters anomaly by regulating epithelial-mesenchymal transition. Twist2 can be regulated by Smad4 and plays an essential role in lens development.

MicroRNAs (miRs) are a group of short, endogenous, non-protein-coding and single-stranded RNAs that regulate gene expression by binding to the 3'-untranslated region (3'UTR) of mRNAs, which results in their degradation or translational repression. The aim of the present study was to investigate the expression and function of miR-335 in human papillary thyroid cancer (PTC). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to quantify the relative miR-335 expression levels in PTC tissues and cell lines. The effect of miR-335 on the proliferation, migration and invasion of PTC cells was assessed by an MTT assay, and transwell migration and invasion assays, respectively. Dual-luciferase reporter assays were employed to explore whether miR-335 directly targeted the 3'UTR of the potential target gene zinc finger E-box binding homeobox 2 (ZEB2). RT-qPCR and western blotting were adopted to assess the effect of miR-335 on the mRNA and protein expression of ZEB2. RT-qPCR revealed that miR-335 was downregulated in PTC tissues and cell lines. The MTT assay and transwell migration and invasion assays demonstrated that the overexpression of miR-335 significantly inhibited the proliferation, migration and invasion of PTC cells. ZEB2 was identified as a direct target of miR-335 with computational analysis, which was confirmed with a dual-luciferase reporter assay, RT-qPCR and western blotting. The knockdown of ZEB2 significantly inhibited the proliferation, migration and invasion of PTC cells, indicating that ZEB2 may be a functional target of miR-335. Taken together, these findings suggested that miR-335 functioned as a tumor suppressor and suppressed the growth and metastatic behavior of PTC cells by targeting ZEB2.

OBJECTIVE

To investigate the expression patterns of ZEB2 and C-myc in epithelial ovarian cancer (EOC) and the associations between their expressions and the pathological features of EOC.

METHODS

The expressions of ZEB2 and C-myc proteins were detected immunohistochemically in 191 cervical cancer tissues and 13 normal ovarian tissues. The relationship between ZEB2 and C-myc protein expressions and the clinicopathological features of EOC was evaluated.

RESULTS

ZEB2 positive expression ratea in EOC tissues and normal ovarian tissues were 49.2% (94/191) and 30.8% (4/13), respectively (P=0.007), and C-myc positive expression rates in the two tissues were 53.9% (103/191) and 15.4% (2/13), respectively (P=0.001). A high expression of ZEB2 was positively correlated with the pathological type of the tumor (P=0.003), FIGO stage (P=0.028), T stage (P=0.002), and N stage (P=0.04), and a high expression of C-myc was positively correlated with FIGO stage (P=0.035), histological grade (P=0.039), and T stage (P=0.002). C-myc and ZEB2 expressions were positively correlated in EOC (P<0.001), and their co-expression in EOC was significantly correlated with T stage (R=0.358, P<0.001) and FIGO stage (P=0.008).

CONCLUSIONS

ZEB2 and C-myc can promote the progression, invasion and metastasis of EOC, and their combined detection may assist in early diagnosis of EOC.

OBJECTIVE

The aggressive manner of ovarian cancer (OVC) cells accounts for the majority of its lethality. Recently, we have shown that placental growth factor (PLGF) promotes metastases of OVC cells through miR-543-regulated MMP7. In the current study, we analyzed the effects of PLGF on another cell invasion associated protein, ZEB2, in OVC cells.

METHODS

The PLGF and ZEB2 levels in OVC tissues were compared to the paired adjacent non-tumor ovary tissue. We modified ZEB2 levels in OVC cells, and examined its effects on PLGF mRNA and protein levels by RT-qPCR and by Western blot, respectively. We also modified PLGF levels in OVC cells, and examined its effects on ZEB2 mRNA and protein levels by RT-qPCR and by Western blot, respectively. Then, we examined the cell invasiveness in PLGF-modified OVC cells in a transwell cell invasion assay. Finally, we used specific signal pathway inhibitors to treat PLGF-modified OVC cells and examined the effects on ZEB2 activation.

RESULTS

PLGF and ZEB2 levels were both significantly increased in OVC tissues, compared to the paired adjacent non-tumor ovary tissue. The PLGF and ZEB2 levels were strongly correlated. ZEB2 modification did not alter PLGF levels. Overexpression of PLGF in OVC cells significantly increased ZEB2 levels and cell invasiveness, while PLGF depletion in OVC cells significantly decreased ZEB2 levels and cell invasiveness. Application of a specific MAPK-p38 inhibitor, but not application of specific inhibitors for MAPK-p42/p44, PI3k/Akt, or JNK signaling pathways, to PLGF-overexpressing OVC cells substantially abolished the PLGF-induced ZEB2 activation.

CONCLUSIONS

PLGF enhances OVC cell invasion through MAPK-p38-dependent activation of ZEB2.

ABSTRAT Alcoholic liver disease (ALD) and its complication continued to be a major health problem throughout the world. Increasing evidence suggests that microRNA (miRNA) that regulate apoptosis, inflammation and lipid metabolism are affected by alcohol in ALD. MiR-200a has emerged as a major regulator in several liver diseases, but its role in ALD has not been elucidated. The aim of this study is to figure out the biological function of miR-200a in ALD and to explore its underlying mechanism. The expression pattern of miR-200a were analyzed in vitro and in vivo, we showed that miR-200a was up-regulated in ALD in AML-12 and primary hepatocyte. We then examined it's effect on cell apoptosis and identified zinc finger E-box binding homeobox 2 (ZEB2; also known as SIP1) as a direct target gene of miR-200a. Furthermore, reintroduction of ZEB2 could reverse the pro-apoptosis of miR-200a on AML-12. Taken together, our study demonstrated that miR-200a regulates the apoptosis of hepatocyte in ALD by directly target ZEB2, both of which could serve as new therapeutic targets for ALD.

Lung cancer is the leading cause of cancer-related deaths worldwide. Epithelial-mesenchymal transition (EMT) is a major event that drives cancer progression. Here we aim to investigate the role of microRNA, miR-145, in regulating EMT of the highly invasive non-small cell lung cancer (NSCLC). Quantitative real-time polymerase chain reaction analysis indicated that miR-145 was downregulated in cancer tissue compared with that in adjacent normal tissue. NSCLC cell lines, namely H1299, PC7, and SPCA-1, also demonstrated miR-145 downregulation, which is correlated well with their invasive ability, assessed by the Matrigel invasion assay. miR-145 overexpression resulted in downregulation of N-cadherin, and downregulation of vimentin and E-cadherin, suggesting a decreased EMT activity. TargetScan analysis predicted that a binding site exists between miR-145 and an oncogene, ZEB2, which was verified using the dual-luciferase assay. Alteration of miR-145 expression also induced inverse effects on ZEB2 expression, and a negative correlation exists between ZEB2 and miR-145 in human tissues. ZEB2 and miR-145 also exerted antagonizing effects on the invasion of NSCLC cells. Therefore, miR-145 is an important molecule in NSCLC that regulates cancer EMT through targeting ZEB2.

The triple-negative breast cancer is the most malignant type of breast cancer. Its pathogenesis and prognosis remain poor despite the significant advances in breast cancer diagnosis and therapy. Meanwhile, long noncoding RNAs (LncRNAs) play a pivotal role in the progression of malignant tumors. In this study, we found that LncRNA-ZEB2-AS1 was dramatically up-regulated in our breast cancer specimens and cells (MDA231), especially in metastatic tumor specimens and highly invasive cells, and high lncRNA-ZEB2-AS1 expression is associated with clinicopathologic features and short survival of breast cancer patients. LncRNA-ZEB2-AS1 promotes the proliferation and metastasis of MDA231 cells in SCID mice. Thus, it is regarded as an oncogene in triple-negative breast cancer. It is mainly endo-nuclear and situated near ZEB2, positively regulating ZEB2 expression and activating the epithelial mesenchymal transition via the PI3K/Akt/GSK3β/Zeb2 signaling pathway. Meanwhile, EGF-induced F-actin polymerization in MDA231 cells can be suppressed by reducing lncRNA-ZEB2-AS1 expression. The migration and invasion of triple-negative breast cancer can be altered through cytoskeleton rearrangement. In summary, we demonstrated that lncRNA-ZEB2-AS1 is an important factor affecting the development of triple-negative breast cancer and thus a potential oncogene target.

The long noncoding RNAs (lncRNAs) have been increasingly appreciated as key players underlying tumourigenesis and hold great potentials as prognostic biomarkers and therapeutic targets. However, their roles in head neck squamous cell carcinoma (HNSCC) have remained incompletely known. Here, we sought to reveal the oncogenic roles and clinical significance of a tumour-associated lncRNA, zinc finger E-box binding homeobox 2 antisense RNA 1 (ZEB2-AS1), in HNSCC. ZEB2-AS1 was aberrantly overexpressed in a fraction of HNSCC samples. Its overexpression significantly associated with large tumour size, cervical node metastasis and reduced overall and disease-free survival. Antisense oligonucleotides (ASO)-mediated ZEB2-AS1 depletion markedly inhibited cell proliferation, migration and invasion while triggered apoptosis in HNSCC cells in part via modulating ZEB2 mRNA stability. Enforced overexpression of ZEB2 largely attenuated the phenotypic changes resulted from ZEB2-AS1 inhibition except the impaired cell proliferation. In addition, ZEB2-AS1 was required for TGF-β1-induced epithelial-mesenchymal transition (EMT) in vitro. Significantly reduced tumour growth and lung metastasis were observed in ZEB2-AS1-depleted cells in HNSCC xenograft animal models. Taken together, our findings reveal that overexpression of ZEB2-AS1 associates with tumour aggressiveness and unfavourable prognosis by serving as a putative oncogenic lncRNA and a novel prognostic biomarker in HNSCC.

Pre-eclampsia (PE) is a pregnancy disease that causes maternal death and threatens the health of newborns. Accumulating evidence has revealed the essential roles of long noncoding RNAs (lncRNAs) in the progression of PE. The present investigation determined lncRNA ZEB2 antisense RNA 1 (ZEB2-AS1) expression in PE and looked into the potential role of ZEB2-AS1 in modulating trophoblastic cell functions. Quantitative real-time polymerase chain reaction evaluated gene expression. Western blot analyzed the placental growth factor (PGF) protein level. Cell counting kit-8 and Transwell invasion assays assessed the proliferative and invasive abilities of placental trophoblast cells, respectively. Wound healing assay determined cell migratory potentials. Dual-luciferase reporter assay assessed the targeting relationship among ZEB2-AS1, miR-149, and PGF. Downregulation of lncRNA ZEB2-AS1 was detected in placentas from patients with PE when compared with those from normal pregnancies. Moreover, ZEB2-AS1 upregulation markedly promoted proliferative, migratory, and invasive potentials in HTR-8/SVneo cells, while knockdown of ZEB2-AS1 had the opposite effects. The effects on HTR-8/SVneo cells mediated by ZEB2-AS1 was correlated with the miR-149/PGF axis. These findings indicate that ZEB2-AS1 contributes to PE progression by affecting cell proliferative and invasive capacities via the miR-149/PGF axis in HTR-8/SVneo cells. In sum, we identified that ZEB2-AS1 was a novel aberrantly expressed lncRNA in the placentas of PE patients and lncRNA ZEB2-AS1 modulated trophoblastic cell line HTR-8/SVneo's proliferative and invasive potentials via targeting the miR-149/PGF axis.

Breast cancer is a major cause of global mortality in women. Curcumin exerts anti-proliferative, anti-migratory and apoptotic effects. The aim of this study was to evaluate gene expression involved in epithelial-mesenchymal transition (EMT). An in vitro model was developed with the MCF-10F immortalized breast epithelial cell line exposed to low radiation doses of high LET (linear energy transfer) α-particles (150 keV/µm) and cultured in the presence of 17β-estradiol (estrogen). The following cell lines were used: i) MCF-10F, normal; ii) Alpha5, pre-tumorigenic, and iii) Tumor2 derived from Alpha5 injected into the nude mice. Our previous results have shown that Alpha5 and Tumor2 increased cell proliferation, anchorage independency, invasive capabilities and tumor formation in nude mice in comparison to control. Results indicated that curcumin decreased expression of EMT-related genes in Tumor2 cell line when compared to its counterpart as E-cadherin, N-cadherin, ZEB2, Twist1, Slug, Axl, vimentin, STAT-3, fibronectin; and genes p53 and caveolin-1, as well as apoptotic genes caspase-3, caspase-8, and others such as cyclin D1 and NFκB. All these changes induced a decrease in migratory and invasive capabilities of such a cell line. Thus, it seems that curcumin may impinge upon apoptosis and metastatic properties of the malignant cells exerting antitumor activity in breast cancer cells transformed by low doses of α-particles and estrogen in vitro.

Oncogenic epithelial-mesenchymal transition (oncEMT) plays important roles in the genesis of cancer stem cells (CSCs), malignant tumor initiation and progression, cancer metastasis, and drug resistance. Although the role of oncEMT in tumorigenesis has recently been extensively studied, the initiation of oncEMT is not clearly understood, and its mechanisms of action are still unknown. Emerging evidence suggests that oncEMT is a complex process, which involves multiple endogenous and exogenous factors. Overexpression of several oncogenes and reprogramming factors in precancerous and cancerous cells, including Ras, Myc, Bmi-1, Oct4, Nanog, Slug, Twist, Zeb1, and Zeb2, may initiate oncEMT and tumorigenesis. Defects in key tumor suppressors, such as p53, PTEN, CCN6 protein, and p21 also are associated with oncEMT. MicroRNA (miRNA) may also play a role in the oncEMT. Furthermore, exogenous factors, including chemical carcinogens, viruses, radiation, hypoxia, and acidic microenvironment, can drive oncEMT. Moreover, various growth factors derived from either malignant tumor cells or tumor-associated non-tumor cells in the cancer microenvironment can promote oncEMT. Together, the endogenous and exogenous factors, as well as a hostile cancer microenvironment, initiate the oncEMT program through diverse signaling pathways and networks. However, the dynamic process of initiating oncEMT and the mechanisms are still incompletely understood. Further characterization of the dynamics and mechanisms of the oncEMT will provide new insights into oncogenesis, as well as identify specific oncEMT markers and targets for early diagnosis of cancer and novel anti-cancer drug discovery.

Colon cancer (CC) is the third most common cancer and the fourth leading cause of cancer-associated death in the world. Long non-coding RNA (lncRNA) ZEB2-AS1 was reported to be dysregulated and play important roles in multiple human cancers. However, the expression level and functions of ZEB2-AS1 in colon cancer is unknown. Here, we firstly observed that ZEB2-AS1 was significantly upregulated in colon cancer and predicted a poor prognosis. Functional assays showed that silencing ZEB2-AS1 expression remarkably inhibited proliferation, suppressed cell cycle transition while induced apoptosis in CC cells. In addition, miR-143 was demonstrated to act as a tumor suppressor and predicted as a downstream target of ZEB2-AS1 in CC. Furthermore, bcl-2 was identified as a direct target of miR-143 and ZEB2-AS1 could regulate the expression of bcl-2 via miR-143 in CC. A rescue assay indicated that downregulation of miR-143 partly abolished the suppressive effect of ZEB2-AS1 silencing on CC cells proliferation. Collectively, our results revealed that ZEB2-AS1 was upregualted and functioned as an oncogene via regulating miR-143/bcl-2 axis in colon cancer. These findings suggest that ZEB2-AS1 may serve a novel biomarker in the diagnosis and a potential therapeutic target in the treatment of colon cancer.

Epithelial-mesenchymal transition (EMT) plays an important role in the development of tumor metastases by facilitating cell migration and invasion. One of the hallmarks of EMT is the diminished expression of E-cadherin and gain of mesenchymal traits, which are regulated by core EMT-inducing transcriptional factors (EMT-TFs), such as Snail/Slug, ZEB1/ZEB2, and Twist1. EMT-TFs are known to be extremely labile proteins, and their protein levels are tightly controlled by the ubiquitin-proteasome system (UPS). Several E3 ubiquitin ligases have been shown to play crucial roles in the regulation of EMT, and genetic aberrations and alterations in these ligases have been detected in human cancer. In this review, we focused on EMT-TFs, describing the UPS controlling their activities and functions in cancer. A deeper understanding of the role of UPS in the regulation of EMT will provide valuable information for the development of effective anti-metastatic drugs to modulate the malignant processes mediated by EMT.

OBJECTIVE

MicroRNAs (miRNAs) have been involved in hepatocarcinogenesis, but little is known on their role in the progression of chronic viral hepatitis. Aim of this study was to identify miRNA signatures associated with stages of disease progression in patients with chronic viral hepatitis.

METHODS

MiRNA expression profile was investigated in liver biopsies from patients with chronic viral hepatitis and correlated with clinical, virological and histopathological features. Relevant miRNAs were further investigated.

RESULTS

Most of the significant changes in miRNA expression were associated with liver fibrosis stages and included the significant up-regulation of a group of miRNAs that were demonstrated to target the master regulators of epithelial-mesenchymal transition ZEB1 and ZEB2 and involved in the preservation of epithelial cell differentiation, but also in cell proliferation and fibrogenesis. In agreement with miRNA data, immunostaining of liver biopsies showed that expression of the epithelial marker E-cadherin was maintained in severe fibrosis/cirrhosis while expression of ZEBs and other markers of epithelial-mesenchymal transition were low or absent. Severe liver fibrosis was also significantly associated with the down-regulation of miRNAs with antiproliferative and tumour suppressor activity. Similar changes in miRNA and target gene expression were demonstrated along with disease progression in a mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis, suggesting that they might represent a general response to liver injury.

CONCLUSIONS

Chronic viral hepatitis progression is associated with the activation of miRNA pathways that promote cell proliferation and fibrogenesis, but preserve the differentiated hepatocyte phenotype.

OBJECTIVE

To analyze the effect of three-dimensional (3D)-arrangement on the expression of epithelial-to-mesenchymal transition markers in pancreatic adenocarcinoma (PDAC) cells.

METHODS

HPAF-II, HPAC, and PL45 PDAC cells were cultured in either 2D-monolayers or 3D-spheroids. Ultrastructure was analyzed by transmission electron microscopy. The expression of E-cadherin, β-catenin, N-cadherin, collagen type I (COL-I), vimentin, α-smooth muscle actin (αSMA), and podoplanin was assayed by confocal microscopy in cells cultured on 12-mm diameter round coverslips and in 3D-spheroids. Gene expression for E-cadherin, Snail, Slug, Twist, Zeb1, and Zeb2 was quantified by real-time PCR. E-cadherin protein level and its electrophoretic pattern were studied by Western blot in cell lysates obtained from cells grown in 2D-monolayers and 3D-spheroids.

RESULTS

The E-cadherin/β-catenin complex was expressed in a similar way in plasma membrane cell boundaries in both 2D-monolayers and 3D-spheroids. E-cadherin increased in lysates obtained from 3D-spheroids, while cleavage fragments were more evident in 2D-monolayers. N-cadherin expression was observed in very few PDAC cells grown in 2D-monolayers, but was more evident in 3D-spheroids. Some cells expressing COL-I were observed in 3D-spheroids. Podoplanin, expressed in collectively migrating cells, and αSMA were similarly expressed in both experimental conditions. The concomitant maintenance of the E-cadherin/β-catenin complex at cell boundaries supports the hypothesis of a collective migration for these cells, which is consistent with podoplanin expression.

CONCLUSIONS

We show that a 3D-cell culture model could provide deeper insight into understanding the biology of PDAC and allow for the detection of marked differences in the phenotype of PDAC cells grown in 3D-spheroids.

The 6%-9% risk of an untoward outcome previously established by Warburton for prenatally detected de novo balanced chromosomal rearrangements (BCRs) does not account for long-term morbidity. We performed long-term follow-up (mean 17 years) of a registry-based nationwide cohort of 41 individuals carrying a prenatally detected de novo BCR with normal first trimester screening/ultrasound scan. We observed a significantly higher frequency of neurodevelopmental and/or neuropsychiatric disorders than in a matched control group (19.5% versus 8.3%, p = 0.04), which was increased to 26.8% upon clinical follow-up. Chromosomal microarray of 32 carriers revealed no pathogenic imbalances, illustrating a low prognostic value when fetal ultrasound scan is normal. In contrast, mate-pair sequencing revealed disrupted genes (ARID1B, NPAS3, CELF4), regulatory domains of known developmental genes (ZEB2, HOXC), and complex BCRs associated with adverse outcomes. Seven unmappable autosomal-autosomal BCRs with breakpoints involving pericentromeric/heterochromatic regions may represent a low-risk group. We performed independent phenotype-aware and blinded interpretation, which accurately predicted benign outcomes (specificity = 100%) but demonstrated relatively low sensitivity for prediction of the clinical outcome in affected carriers (sensitivity = 45%-55%). This sensitivity emphasizes the challenges associated with prenatal risk prediction for long-term morbidity in the absence of phenotypic data given the still immature annotation of the morbidity genome and poorly understood long-range regulatory mechanisms. In conclusion, we upwardly revise the previous estimates of Warburton to a morbidity risk of 27% and recommend sequencing of the chromosomal breakpoints as the first-tier diagnostic test in pregnancies with a de novo BCR.

Mowat-Wilson syndrome (MWS) is a rare genetic condition where variable and multiple congenital anomalies including Hirschsprung's disease, intellectual disability, and prominent facial features are present. At molecular level, MWS is characterized by many different described mutations in the zinc finger E-box protein 2 (ZEB2) gene, ultimately leading to loss of gene function. This report is the first to describe the association of MWS with two different asynchronous malignant brain tumors (medulloblastoma and glioblastoma) occurring in a child.

MicroRNAs (miRNAs) are frequently dysregulated in a variety of human cancers, including gastric carcinoma. To improve our understanding of the role of miRNAs in gastric carcinoma and potential identify novel biomarkers or therapeutic agents, we performed microarray analysis to identify differentially expressed miRNAs in gastric carcinoma, compared with paired non-cancerous gastric tissues. We identified significantly differentially expressed miRNAs in gastric carcinoma tissues, including miR-506. We validated the microarray results by quantitative reverse transcription polymerase chain reaction in 26 specimens and confirmed significant downregulation of miR-506 in gastric carcinoma. Bioinformatics analysis predicted ZEB2 (zinc finger E-box-binding homeobox 2) as a potential target of miR-506. MiR-506 levels and ZEB2 levels were inversely correlated in gastric carcinoma, and low miR-506 levels in gastric carcinoma were associated with poor prognosis. Overexpression of miR-506 in gastric carcinoma cells significantly inhibited cell migration and invasion, while depletion of miR-506 in gastric carcinoma cells significantly increased cell migration and invasion. Transplantation of miR-506-overexpressing gastric carcinoma cells developed significantly smaller tumor, compared to the control. Thus, our results suggest that miR-506 may function as a tumor suppressor and targets and inhibits ZEB2 in gastric carcinoma.

The E-cadherin loss has frequently been associated with transcriptional repression mediated by transcription factors, such as the Zinc Finger E-Box Binding Homeobox-2 (ZEB2). Invasive micropapillary carcinomas (IMPCs) of the breast are aggressive neoplasms frequently related to lymph node metastasis and poor overall survival. In the canine mammary gland, IMPCs has just been reported and, based on its behavioral similarity with the human IMPCs, appears to be a good spontaneous model to this human entity. This study aimed to evaluate the relationship between E-cadherin and ZEB2 in a spontaneous canine model of invasive micropapillary carcinoma of the mammary gland. The correlation among gene expression (ZEB2 and CDH1) and clinicopathological findings was also explored. Nineteen cases of IMPC of the canine mammary gland were obtained, protein and mRNA expression were investigated through immunohistochemistry and RNA In Situ Hybridization, respectively. To better understand the relationship between E-cadherin and ZEB2, immunofluorescence was performed in canine IMPCs. Immunohistochemically, most of IMPCs showed 1+ (14/19, 73.7%) for E-cadherin; and positivity for ZEB2 was diagnosed in 47.4% of the IMPCs. Regarding the RNA In Situ Hybridization (ISH), most of IMPCs showed 4+ and 0+ for E-cadherin (CDH1) and ZEB2 respectively. Through immunofluorescence, the first and second more frequent combinatorial group were E-cadherin+ZEB2- and E-cadherin+ZEB2+; neoplastic cells showing concomitantly weak expression for E-cadherin and positivity for ZEB2 were frequently observed. A negative correlation was observed between E-cadherin and progesterone receptor expression in IMPCs. Based on these results, canine mammary IMPCs show E-cadherin lost and, at times reveals nuclear positivity for the transcription factor ZEB2 that seems to exert transcriptional repression of the CDH1.

Background: Accumulating reports have demonstrated that long-noncoding RNAs (lncRNAs) play critical roles in the pathological progression of colorectal cancer (CRC). However, the role of lncRNA zinc finger E-box binding homeobox 2 antisense RNA 1 (ZEB2-AS1) in CRC remains largely unknown. Methods: The authors detected the ZEB2-AS1 expression in CRC tissue sample and CRC cell lines. The effects of ZEB2-AS1 on CRC were identified through in vitro assays (i.e., transwell assay, wound-healing assay, immunofluorescence assay, and Western blot) in a ZEB2-AS1 knockdown system. The molecular mechanism of ZEB2-AS1 was explored via bioinformatic tools, quantitative real-time polymerase chain reaction (qRT-PCR), dual-luciferase reporter assay, RNA immunoprecipitation assay, and so on. Moreover, a series of gain-of-function experiments were performed to identify the effect of ZEB2-AS1 and miR-1205 on epithelial-to-mesenchymal transition (EMT) in CRC cells. Results: This analysis clarified that ZEB2-AS1 was upregulated in both CRC tissue sample and cells lines; meanwhile, the high expression of ZEB2-AS1 was correlated with poor overall survival rate. ZEB2-AS1 knockdown significantly suppresses the EMT in CRC cells. Furthermore, the authors identified that the expression of ZEB2-AS1 was negatively correlated with expression of miR-1205, and CRKL could be a direct target of miR-1205. Through the gain-of-function experiments, they found that ZEB2-AS1 accelerates EMT in CRC cells via modulating the expression of miR-1205 and CRKL. Conclusion: Taken together, this study revealed that ZEB2-AS1 accelerates EMT in CRC through the miR-1205/CRKL pathway, suggesting that ZEB2-AS1 may potentially serve as a target of CRC.

The present study aims to investigate the roles of TCF4 and its underlying mechanism in colorectal cancer (CRC). Doxorubicin-resistant DLD-1 (DLD1 DR), TCF4 overexpression, and TCF4 knockdown cell lines were constructed. A flow cytometer was used to analyze frequencies of CD133⁺ cell in the DLD1 and DLD1 DR cells. Quantitative real-time PCR (qPCR) was used to determine the expressions of cancer stem cell (CSC) makers. Stemness of CRC cells were determined using tumorsphere formation assay. The correlation between TCF4 and ZEB1/ZEB2 were determined using public data from The Cancer Genome Atlas (TCGA) datasets. ZEB1/ZEB2 overexpression cell lines were constructed and cell viabilities were then determined using MTT and colony formation assays. TCF4 overexpression promoted proliferation of CRC cell lines and relative expressions of TCF4 were significantly increased in the DLD1 DR cells. TCF4 overexpression promoted CRC cell doxorubicin resistance, whereas TCF4 knockdown significantly decreased doxorubicin resistance. Additionally, TCF4 overexpression also significantly increased frequencies of CSC cells, expressions of CSC markers, and CRC ability to form tumorsphere. Furthermore, TCF4 promoted ZEB1 and ZEB2 expression, leading to CRC proliferation and doxorubicin resistance. TCF4 promoted CRC doxorubicin resistance and stemness by regulating expressions of ZEB1 and ZEB2.

In the present study, hereditary non-polyposis colorectal cancer (HNPCC) susceptibility genes were screened for using whole exome sequencing in 3 HNPCC patients from 1 family and using single nucleotide polymorphism (SNP) genotyping assays in 96 other colorectal cancer and control samples. Peripheral blood was obtained from 3 HNPCC patients from 1 family; the proband and the proband's brother and cousin. High-throughput sequencing was performed using whole exome capture technology. Sequences were aligned against the HAPMAP, dbSNP130 and 1,000 Genome Project databases. Reported common variations and synonymous mutations were filtered out. Non-synonymous single nucleotide variants in the 3 HNPCC patients were integrated and the candidate genes were identified. Finally, SNP genotyping was performed for the genes in 96 peripheral blood samples. In total, 60.4 Gb of data was retrieved from the 3 HNPCC patients using whole exome capture technology. Subsequently, according to certain screening criteria, 15 candidate genes were identified. Among the 96 samples that had been SNP genotyped, 92 were successfully genotyped for 15 gene loci, while genotyping for HTRA1 failed in 4 sporadic colorectal cancer patient samples. In 12 control subjects and 81 sporadic colorectal cancer patients, genotypes at 13 loci were wild-type, namely DDX20, ZFYVE26, PIK3R3, SLC26A8, ZEB2, TP53INP1, SLC11A1, LRBA, CEBPZ, ETAA1, SEMA3G, IFRD2 and FAT1. The CEP290 genotype was mutant in 1 sporadic colorectal cancer patient and was wild-type in all other subjects. A total of 5 of the 12 control subjects and 30 of the 81 sporadic colorectal cancer patients had a mutant HTRA1 genotype. In all 3 HNPCC patients, the same mutant genotypes were identified at all 15 gene loci. Overall, 13 potential susceptibility genes for HNPCC were identified, namely DDX20, ZFYVE26, PIK3R3, SLC26A8, ZEB2, TP53INP1, SLC11A1, LRBA, CEBPZ, ETAA1, SEMA3G, IFRD2 and FAT1.