Epithelial-mesenchymal Transition Marker Genes Research Articles

Integrative Analysis Reveals STC2 as a Prognostic Biomarker of Laryngeal Squamous Cell Carcinoma.

Stanniocalcin 2 (STC2) is involved in many tumour types, but it remains unclear what its biological function is in laryngeal squamous cell carcinoma (LSCC). Therefore, we investigated STC2's expression, potential function, and prognostic significance of in LSCC. The expression and prognosis of STC2 in LSCC were described using the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. In the TCGA database, the relationship between STC2 and immune infiltration, expression of immune cell chemokine and receptor genes, immune cell molecular marker genes, and epithelial‒mesenchymal transition (EMT) marker genes were analysed. The biological processes involved in STC2 and its expression-related genes were analysed comprehensively using bioinformatics. The single-gene ceRNA network of STC2 was constructed in the TCGA database. Finally, LSCC patients' tumour tissue STC2 expression was verified. STC2 silencing with the RNAi technique was used for the determination of cellular functions in a laryngeal cancer cell line. STC2 expression was higher in most tumours, including LSCC, than in normal tissues and was associated with poor prognosis. The relative proportions of naïve B, plasma, follicular helper T, and macrophage M0 cells in LSCC and normal samples differed significantly. STC2 expression correlated significantly positively with that of TGFB1 (biomarker of Tregs) and significantly negatively with that of D79A and CD19 (biomarkers of B cells). Furthermore, STC2 affected chemokine and receptor gene expression in immune cells. STC2 expression correlated with EMT marker gene expression in LSCC. STC2 was enriched in the PI3K/AKT signalling pathway, extracellular matrix (ECM) organisation, ECM-receptor interaction, and other tumour-related signalling pathways. STC2 was highly expressed in our clinical samples. N-cadherin and vimentin expression were decreased in the TU686 cell line after successful silencing of STC2, indicating that high STC2 expression may prompt LSCC cells to adopt a mesenchymal cell phenotype. STC2 silencing substantially reduced proliferation and migration in the TU686 cell line. STC2 may be a promising predictive biomarker for tumours, providing new approaches for LSCC diagnosis and treatment monitoring.

Copper Exposure Induces Epithelial-Mesenchymal Transition-Related Fibrotic Change via Autophagy and Increase Risk of Lung Fibrosis in Human

Copper is an essential trace element involved in several vital biological processes of the human body. However, excess exposure to copper caused by occupational hazards and environmental contamination, such as food, water, and air, damages human health. In this study, in vitro cell culture model and epidemiologic studies were conducted to evaluate the effect of copper on lung fibrosis. In vitro, treatment of CuSO4 in lung epithelial cells at 100 μM consistently decreases cell viability in alveolar type (A549) and human bronchial epithelial (HBE) cells. CuSO4 promotes epithelial-mesenchymal transition (EMT) as shown by increased cell migration and increased EMT marker and fibrotic gene expressions. Besides, CuSO4 induced cell autophagy, with an increased LC3, PINK, and decreased p62 expression. Inhibition of ROS by N-acetylcysteine reversed the CuSO4-induced PINK1, LC3, and Snail expressions. Inhibition of autophagy by chloroquine reverses the CuSO4-induced EMT changes. Nature flavonoids, especially kaempferol, and fustin, were shown to inhibit Copper-induced EMT. In humans, a unit increase in urinary copper concentration was significantly associated with an increased risk of lung fibrotic changes (odds ratio [OR] = 1.17, 95% confidence interval [CI] = 1.01-1.36, p = 0.038). These results indicated that Copper is a risk factor for lung fibrosis through activation of the ROS-autophagy-EMT pathway, which can be reversed by flavonoids.

Tumor-Educated Platelet Extracellular Vesicles: Proteomic Profiling and Crosstalk with Colorectal Cancer Cells.

Platelet-cancer cell interactions modulate tumor metastasis and thrombosis in cancer. Platelet-derived extracellular vesicles (EVs) can contribute to these outcomes. We characterized the medium-sized EVs (mEVs) released by thrombin-stimulated platelets of colorectal cancer (CRC) patients and healthy subjects (HS) on the capacity to induce epithelial-mesenchymal transition (EMT)-related genes and cyclooxygenase (COX)-2(PTGS2), and thromboxane (TX)B2 production in cocultures with four colorectal cancer cell lines. Platelet-derived mEVs were assessed for their size distribution and proteomics signature. The mEV population released from thrombin-activated platelets of CRC patients had a different size distribution vs. HS. Platelet-derived mEVs from CRC patients, but not from HS, upregulated EMT marker genes, such as TWIST1 and VIM, and downregulated CDH1. PTGS2 was also upregulated. In cocultures of platelet-derived mEVs with cancer cells, TXB2 generation was enhanced. The proteomics profile of mEVs released from activated platelets of CRC patients revealed that 119 proteins were downregulated and 89 upregulated vs. HS. We show that mEVs released from thrombin-activated platelets of CRC patients have distinct features (size distribution and proteomics cargo) vs. HS and promote prometastatic and prothrombotic phenotypes in cancer cells. The analysis of platelet-derived mEVs from CRC patients could provide valuable information for developing an appropriate treatment plan.

Immunological and Genetic Characterization of Patients With Head and Neck Cancer who Developed Recurrence.

The recurrence rate of head and neck squamous cell carcinoma (HNSCC) remains high; thus the control of recurrence is a clinical problem to be challenged. To clarify the precise mechanism, specific immunological biomarkers responsible for recurrence were investigated. The expression levels of immune response-associated and Shizuoka Cancer Center 820 cancer-associated genes, and genetic mutations from whole-exome sequencing were compared between HNSCC patients who developed recurrence (n=8) and HNSCC patients who did not develop recurrence (n=19) using a volcano plot analysis. Cytokine and epithelial-mesenchymal transition marker genes were analyzed using quantitative PCR. Tumor-infiltrating lymphocytes, immune checkpoint molecules, and human papilloma virus status were investigated using immunohistochemistry (IHC). Twenty-seven evaluable patients with HNSCCs received radiation therapy after surgery. Recurrence was identified in 8 patients. TP53 mutations tended to be higher in patients who developed recurrence than in those who did not develop recurrence (75% vs. 31.6%). Gene expression profiling showed the down-regulation of T cell activation genes (ICOS, CD69 and CD83) and the upregulation of the ERBB4, EGFR, VEGF, HIF1A, TGFB1, TWIST1, IL-8, and PAX7 genes, which suggested the activation of the TP53 mutation-TGF-β1-PAX7 pathway and epithelial-mesenchymal transition. Additionally, IHC indicated a tendency toward a reduction in T cell accumulation and an increase in M2-type macrophage infiltration in tumors that recurred. A TP53 mutation-mediated immune-suppressive state in the tumor microenvironment and TGF-β1-PAX7-mediated EMT might contribute to the promotion of recurrence in patients with HNSCC after postoperative radiotherapy.

Serglycin Is Involved in TGF-β Induced Epithelial-Mesenchymal Transition and Is Highly Expressed by Immune Cells in Breast Cancer Tissue.

Serglycin is a proteoglycan highly expressed by immune cells, in which its functions are linked to storage, secretion, transport, and protection of chemokines, proteases, histamine, growth factors, and other bioactive molecules. In recent years, it has been demonstrated that serglycin is also expressed by several other cell types, such as endothelial cells, muscle cells, and multiple types of cancer cells. Here, we show that serglycin expression is upregulated in transforming growth factor beta (TGF-β) induced epithelial-mesenchymal transition (EMT). Functional studies provide evidence that serglycin plays an important role in the regulation of the transition between the epithelial and mesenchymal phenotypes, and it is a significant EMT marker gene. We further find that serglycin is more expressed by breast cancer cell lines with a mesenchymal phenotype as well as the basal-like subtype of breast cancers. By examining immune staining and single cell sequencing data of breast cancer tissue, we show that serglycin is highly expressed by infiltrating immune cells in breast tumor tissue.

Excessive activation of IL-33/ST2 in cancer-associated fibroblasts promotes invasion and metastasis in ovarian cancer.

Ovarian cancer is highly prevalent and has high mortality rates due to metastasis and relapse. The cross communication between cancer-associated fibroblasts (CAFs) and cancer-associated macrophages (CAMs) in the ovarian tumor microenvironment leads to cancer cell invasion and metastasis. However, the role of overproduction of IL-33/ST2 in the CAFs of ovarian cancer is still unclear. The expression of IL-33, ST2, apoptosis-related proteins and epithelial-mesenchymal transition (EMT) markers was measured by western blotting. Primary normal fibroblasts and CAFs from ovarian cancerous tissue were isolated and cultured in vitro, and the medium was used to stimulate blood-derived monocytes. Flow cytometry analysis was used to detect the frequency of M2-like macrophages in blood-derived monocytes from patients with ovarian cancer. Cell invasion were evaluated using Transwell assays. A xenograft model was used to study tumor growth in ST2-knockout and wild-type NOD-SCID mice. The results demonstrated higher expression of IL-33 and ST2 in carcinoma tissues compared with in para-carcinoma tissues, and there was a survival improvement associated with elevated IL-33. IL-33 and culture supernatants from CAFs, rather than normal ovarian fibroblasts, led to a higher expression of M2 macrophage marker genes in human blood-derived monocytes. Invasion and migration were aggravated in COC1 cells co-cultured with CAF-induced CAMs, and the EMT marker genes were upregulated. It was reported that EMT marker genes were downregulated and tumor volumes were significantly reduced in ST2-deficient mice. Overall, the IL-33/ST2 axis in ovarian cancer might integrate IL-33-expressing CAFs with M2 type-like CAMs, which aggravated invasion and metastasis by promoting EMT.

Next Potential Therapeutic Targets in Rheumatoid Arthritis are Molecules Regulating Inflammatory Transition of Synovium

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic joint inflammation and destruction. The affected synovium becomes the basis of the inflammatory milieu by recruiting immune cells including T cells, B cells, monocytes, macrophages and granulocytes etc., and activates osteoclasts leading to joint destruction and dysfunction. If this inflammatory environment can be restored, destructive arthritis in RA can be prevented. With the introduction of molecular-targeted agents (MTAs) at the beginning of this century, RA has become a controllable disease. Nevertheless, effective drugs including MTAs require continuous administration. This is because they are still unable to eliminate the cause of the disease. Patients with refractory RA often show a decreased response to treatment over time, suggesting that there underlie the irreversible traits of cytokine dysregulation. For the treatment aiming a closer-to-cure condition, it is necessary to find new approach to restore such traits. The RA synovium has two abnormalities: morphological and functional ones. The first is the loss of the single-cell-layer structure surrounding the joint cavity followed by abnormal proliferation to form a tumor-like tissue called pannus which is comparable to epithelial-mesenchymal transition (EMT), and the second is the autonomous activation of inflammation-related genes due to epigenetic changes in DNA and the decrease in immune regulatory response due to metabolic changes, etc. Especially, these functional abnormalities seem to be associated with traits of cytokine dysregulation in RA synovium. Recent chromatin immunoprecipitation sequencing analysis with synovial fibroblasts has shown that EMT-like changes are linked to changes in cytokine production. In RA, compared to osteoarthritis, non-autoimmune joint disease, there were activating histone modifications at the IL-6 locus. Intriguingly, such activation changes were observed also in the loci of EMT marker genes, SNAI1 and COL1A1. These epigenetic changes in the RA synovium seem to be related to irreversible, fixed traits that continue the inflammatory response. Candidate targets of the trait-restoring therapy for RA include molecules involved in epigenetic plasticity that can restore irreversible changes toward inflammatory nature in the RA synovium.

Culturing Chinese hamster ovary cells on cyclo olefin polymer triggers epithelial-mesenchymal transition and spheroid formation, which increases the foreign gene expression driven by the Moloney murine leukemia virus long terminal repeat promoter.

Chinese hamster ovary (CHO) cells are frequently used for recombinant protein production (RPP) as a host. While the RPP has been proven successful, there is still a compelling need for further improvement. Cyclo olefin polymer (COP) is a plastic material widely utilized due to its properties including its low protein absorption. We applied this as a raw material for RPP cell culture to see if the COP is suitable. A recombinant CHO cell line expressing the human erythropoietin (hEPO) gene under the control of the Moloney murine leukemia virus-long terminal repeat (MMLV-LTR) was established. When the cells were cultured in a dish made from COP, the cells attached to the bottom, and then started to float and form spheroids. RNASeq data analysis suggested the epithelial-mesenchymal transition (EMT) was triggered with receptor tyrosine kinase activation shortly after cultivation. It coincided with the hEPO transcription increase. After the cell floating, though EMT marker gene expression subsided, a hEPO expression increase sustained. When fibronectin was applied to COP dish surface, the cell floating was suppressed and hEPO expression decreased. We then treated cells with MβCD, a drug that destroys the lipid raft, eliminating molecules in the raft. This facilitated cell floating and spheroid formation coincided with hEPO expression enhancement. These results suggest interactions between a cell and COP surface might trigger the EMT and the subsequent event, both of which activated the MMLV-LTR promoter. Thus, employing COP for culturing cells, a potent RPP system could be established with its advantage for efficient protein purification.

Direct suppression of human islet dedifferentiation, progenitor genes, but not epithelial to mesenchymal transition by liraglutide

β-cell dedifferentiation has been accounted as one of the major mechanisms for β-cell failure; thus, is a cause to diabetes. We study direct impacts of liraglutide treatment on ex vivo human dedifferentiated islets, and its effects on genes important in endocrine function, progenitor states, and epithelial mesenchymal transition (EMT). Human islets from non-diabetic donors, were purified and incubated until day 1 and day 4, and were determined insulin contents, numbers of insulin (INS+) and glucagon (GCG+) cells. The islets from day 3 to day 7 were treated with diabetic drugs, the long acting GLP-1 receptor agonist, liraglutide. As observed in pancreatic islets of type 2 diabetic patients, ex vivo dedifferentiated islets showed more than 50% reduced insulin contents while number of glucagon increased from 10% to about 20%. β-cell specific genes: PDX1, MAFA, as well as β-cell functional markers: GLUT1 and SUR1, were significantly depleted more than 40%. Notably, we found increased levels of glucagon regulator, ARX and pre-glucagon transcripts, and remarkably upregulated progenitor expressions: NEUROG3 and ALDH1A identified as β-cell dysfunction markers in diabetic models. Hyperglucagonemia was often observed in type 2 patients that could lead to over production of gluconeogenesis by the liver. Liraglutide treatments resulted in decreased number of GCG+ cells, increased numbers of GLP-1 positive cells but did not alter elevated levels of EMT marker genes: ACTA2, CDH-2, SNAIL2, and VIM. These effects of liraglutide were blunted when FOXO1 transcripts were depleted. This work illustrates that ex vivo human isolated islets can be used as a tool to study different aspects of β-cell dedifferentiation. Our novel finding suggests a role of GLP-1 pathway in beta-cell maintenance in FOXO1-dependent manner. Importantly, dedifferentiated islets ex vivo is a useful model that can be utilized to verify the actions of potential drugs to diabetic β-cell failure.

Identification of new hypoxia-regulated epithelial-mesenchymal transition marker genes labeled by H3K4 acetylation.

Hypoxia-induced epithelial-mesenchymal transition (EMT) involves the interplay between chromatin modifiers histone deacetylase 3 (HDAC3) and WDR5. The histone mark histone 3 lysine 4 acetylation (H3K4Ac) is observed in the promoter regions of various EMT marker genes (eg, CDH1 and VIM). To further define the genome-wide location of H3K4Ac, a chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) analysis was performed using a head and neck squamous cell carcinoma (HNSCC) FaDu cell line under normoxia and hypoxia. H3K4Ac was found to be located mainly around the transcription start site. Coupled with analysis of gene expression by RNA sequencing and using a HDAC3 knockdown cell line, 10 new genes (BMI1, GLI1, SMO, FOXF1, SIRT2, etc) that were labeled by H3K4Ac and regulated by HDAC3 were identified. Overexpression or knockdown of GLI1/SMO increased or repressed the in vitro migration and invasion activity in OECM-1/FaDu cells, respectively. In HNSCC patients, coexpression of GLI1 and SMO in primary tumors correlated with metastasis. Our results identify new EMT marker genes that may play a significant role in hypoxia-induced EMT and metastasis and further provide diagnostic and prognostic implications.

Epigenetic Modifications of the Liver Tumor Cell Line HepG2 Increase Their Drug Metabolic Capacity.

Although human liver tumor cells have reduced metabolic functions as compared to primary human hepatocytes (PHH) they are widely used for pre-screening tests of drug metabolism and toxicity. The aim of the present study was to modify liver cancer cell lines in order to improve their drug-metabolizing activities towards PHH. It is well-known that epigenetics is strongly modified in tumor cells and that epigenetic regulators influence the expression and function of Cytochrome P450 (CYP) enzymes through altering crucial transcription factors responsible for drug-metabolizing enzymes. Therefore, we screened the epigenetic status of four different liver cancer cell lines (Huh7, HLE, HepG2 and AKN-1) which were reported to have metabolizing drug activities. Our results showed that HepG2 cells demonstrated the highest similarity compared to PHH. Thus, we modified the epigenetic status of HepG2 cells towards ‘normal’ liver cells by 5-Azacytidine (5-AZA) and Vitamin C exposure. Then, mRNA expression of Epithelial-mesenchymal transition (EMT) marker SNAIL and CYP enzymes were measured by PCR and determinate specific drug metabolites, associated with CYP enzymes by LC/MS. Our results demonstrated an epigenetic shift in HepG2 cells towards PHH after exposure to 5-AZA and Vitamin C which resulted in a higher expression and activity of specific drug metabolizing CYP enzymes. Finally, we observed that 5-AZA and Vitamin C led to an increased expression of Hepatocyte nuclear factor 4α (HNF4α) and E-Cadherin and a significant down regulation of Snail1 (SNAIL), the key transcriptional repressor of E-Cadherin. Our study shows, that certain phase I genes and their enzyme activities are increased by epigenetic modification in HepG2 cells with a concomitant reduction of EMT marker gene SNAIL. The enhancing of liver specific functions in hepatoma cells using epigenetic modifiers opens new opportunities for the usage of cell lines as a potential liver in vitro model for drug testing and development.

RASSF1C regulates miR-33a and EMT marker gene expression in lung cancer cells.

RASSF1C functions as an oncogene in lung cancer cells by stimulating proliferation and migration, and reducing apoptosis. Further, RASSF1C up-regulates important protein-coding and non-coding genes involved in lung cancer cell growth, including the stem cell self-renewal gene, piwil1, and small noncoding PIWI-interacting RNAs (piRNAs). In this article, we report the identification of microRNAs (miRNAs) that are modulated in lung cancer cells over-expressing RASSF1C. A lung cancer-specific miRNA PCR array screen was performed to identify RASSF1C target miRNA-coding genes using RNA isolated from the lung cancer cell line H1299 stably over-expressing RASSF1C and corresponding control. Several modulated miRNA genes were identified that are important in cancer cell proliferation and survival. Among the miRNAs down-regulated by RASSF1C is miRNA-33a-5p (miRNA-33a), which functions as a tumor suppressor in lung cancer cells. We validated that over-expression of RASSF1C down-regulates miR-33a expression and RASSF1C knockdown up-regulates miR-33a expression. We found that RASSF1C over-expression also increases β-catenin, vimentin, and snail protein levels in cells over-expressing miR-33a. In addition, we found that RASSF1C up-regulates the expression of ABCA1 mRNA which is a known target of miR-33a. Our findings suggest that RASSF1C may promote lung epithelial mesenchymal transition (EMT), resulting in the development of a lung cancer stem cell phenotype, progression, and metastasis, in part, through modulation of miR-33a expression. Our findings reveal a new mechanistic insight into how RASSF1C functions as an oncogene.

Ahnak promotes tumor metastasis through transforming growth factor-\u03b2-mediated epithelial-mesenchymal transition

Previously, we reported a molecular mechanism by which Ahnak potentiates transforming growth factor-β (TGFβ) signaling during cell growth. Here, we show that Ahnak induces epithelial-mesenchymal transition (EMT) in response to TGFβ. EMT phenotypes, including altered in cell morphology, and expression patterns of various EMT marker genes were detected in HaCaT keratinocytes transfected with Ahnak-specific siRNA. Knockdown of Ahnak expression in HaCaT keratinocytes resulted in attenuated cell migration and invasion. We found that Ahnak activates TGFβ signaling via Smad3 phosphorylation, leading to enhanced Smad3 transcriptional activity. To validate function of Ahnak in EMT of B16F10 cells having high metastatic and tumorigenic properties, we established B16F10 cells with stable knockdown of Ahnak. N-cadherin expression and Smad3 phosphorylation were significantly decreased in B16F10-shAhnak cells, compared to B16F10-shControl cells after treatment of TGFβ. Moreover, TGFβ failed to induce cell migration and cell invasion in B16F10-shAhnak cells. To determine whether Ahnak regulates the metastatic activity of B16F10 cells, we established a lung metastasis model in C57BL/6 mice via tail vein injection of B16F10-shAhnak cells. Lung metastasis was significantly suppressed in mice injected with B16F10-shAhnak cells, compared to those injected with B16F10-shControl cells. Taken together, we propose that TGFβ-Ahnak signaling axis regulates EMT during tumor metastasis.

Potential role of periodontal pathogens in compromising epithelial barrier function by inducing epithelial-mesenchymal transition.

Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells acquire a mesenchymal-like phenotype and this may be induced by exposure to gram-negative bacteria. It has been proposed that EMT is responsible for compromising epithelial barrier function in the pathogenesis of several diseases. However, the possible role of EMT in the pathogenesis of periodontitis has not previously been investigated. The aim of this study therefore was to investigate whether gram-negative, anaerobic periodontal pathogens could trigger EMT in primary oral keratinocytes in vitro. Primary oral keratinocytes were harvested from labial mandibular mucosa of Wistar Han rats. Cells were exposed to heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis (100 bacteria/epithelial cell) and to 20μg/mL of Escherichia coli lipopolysaccharide over an 8-day period. Exposure to bacteria did not significantly change epithelial cell number or vitality in comparison with unstimulated controls at the majority of time-points examined. Expression of EMT marker genes was determined by semiquantitative RT-PCR at 1, 5, and 8days following stimulation. The expression of EMT markers was also assessed by immunofluorescence (E-cadherin and vimentin) and using immunocytochemistry to determine Snail activation. The loss of epithelial monolayer coherence, in response to bacterial challenge, was determined by measuring trans-epithelial electrical resistance. The induction of a migratory phenotype was investigated using scratch-wound and transwell migration assays. Exposure of primary epithelial cell cultures to periodontal pathogens was associated with a significant decrease in transcription (~3-fold) of E-cadherin and the upregulation of N-cadherin, vimentin, Snail, matrix metalloproteinase-2 (~3-5 fold) and toll-like receptor 4. Bacterial stimulation (for 8 days) also resulted in an increased percentage of vimentin-positive cells (an increase of 20% after stimulation with P.gingivalis and an increase of 30% after stimulation with F.nucleatum, compared with controls). Furthermore, periodontal pathogens significantly increased the activation of Snail (60%) and cultures exhibited a decrease in electrical impedance (P<.001) in comparison with unexposed controls. The migratory ability of the cells increased significantly in response to bacterial stimulation, as shown by both the number of migrated cells and scratch-wound closure rates. Prolonged exposure of primary rat oral keratinocyte cultures to periodontal pathogens generated EMT-like features, which introduces the possibility that this process may be involved in loss of epithelial integrity during periodontitis.

Effect of transforming growth factor-β1 on the invasion and migration of human lung adenocarcinoma cells and epithelial mesenchymal transformation and autophagy

Objective To investigate the effect of transforming growth factor-β1 (TGF-β1) on the invasion and migration of lung adenocarcinoma cells and the epithelial-mesenchymal transition (EMT) and autophagy of epithelial cells. Methods Transwell assay was used to detect the effect of TGF-β1 on the migration and invasion of lung adenocarcinoma A549 and SK-LU-1 cells. The changes of autophagy in A549 cells induced by TGF-β1 were examined by immunofluorescence. The effect of TGF-β1 on the expression of EMT marker and autophagy regulatory genes in A549 cells was detected by Western blotting. Results The interference efficiency of sh-TGF-β1 was about 60% in A549 and SK-LU-1 cells, and the overexpression efficiency in GV358-TGF-β1 overexpression group was more than 4 times. The migration assay showed that in A549 cells, the migration was 1.02±0.06 in shNC group, and 5.14±0.43 in TGF-β1 overexpression group (t=16.440, P=0.004); In SK-LU-1 cells, the migration was 1.04±0.08 in shNC group, and 4.92±0.48 in TGF-β1 overexpression group (t=13.810, P=0.005). The invasion assay showed that in A549 cells, the invasion rate was 0.96±0.07 in the shNC group, and 4.28±0.51 in the TGF-β1 overexpression group (t=11.170, P=0.007); In SK-LU-1 cells, the invasion rate was 1.03±0.05 in the shNC group, and 4.11±0.36 in the TGF-β1 overexpression group (t=10.410, P=0.009). The results of immunofluorescence showed that as compared with the control group, the number of autophagic bodies punctured in TGF-β1 overexpression group was significantly increased (t=22.340, P=0.000), and the fluorescence intensity was significantly increased. The results of Western blotting revealed the expression of E-cadherin in TGF-β1 overexpression group was significantly decreased, and that of Vimentin, Twist and Snail significantly increased as compared with the control group. The autophagy-related protein Beclin1 and phosphorylated mammalian target of rapamycin (p-mTOR) were significantly upregulated. The results in the TGF-β1 interference group showed the opposite trend to the TGF-β1 over-expression group. Conclusion In lung adenocarcinoma cells, autophagy and EMT induced by TGF-β1 positive expression may be related to their ability to enhance invasion and migration of lung adenocarcinoma cells. Key words: Lung adenocarcinoma; Transforming growth factor-β1; Migration; Invasion; Epithelial-mesenchymal transition; Autophagy

Effects of knockdown of Stat5 on invasion and epithelial mesenchymal transition of thyroid carcinoma TT cells

Objective To investigate the effects of knockdown of signal transducer and activator of transcription 5 (Stat5) on invasion and epithelial mesenchymal transition (EMT) of thyroid carcinoma TT cells. Methods Thyroid carcinoma TT cells were cultured and divided into Stat5-small interfering RNA (siRNA) group and NC-siRNA group, transfected with Stat5 siRNA and negative control NC-siRNA respectively. After transfection, the numbers of invasive cells were determined by Transwell model and the expressions of matrix metalloproteinase (MMP) family genes, EMT marker genes, angiogenesis genes in the cells were determined by fluorescent quantitative PCR. Results The numbers of invasive cells in Stat5-siRNA group were significantly lower than those in NC-siRNA group (42.39±5.82 vs. 64.41±8.49, t=-4.784, P=0.001; 51.23±6.38 vs. 78.54±9.52, t=-5.329, P<0.001; 60.35±8.35 vs. 98.42±11.25, t=-6.076, P<0.001) after the transfection of siRNA for 12 hours, 18 hours and 24 hours. Twenty-four hours after transfection of siRNA, the mRNA expressions of MMP1, MMP2, MMP9, MMP13, N-cadherin, Vimentin, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiogenin (Ang)-1 and Ang-2 in Stat5-siRNA group were significantly lower than those in NC-siRNA group (0.42±0.07 vs. 1.03±0.15, t=-8.240, P<0.001; 0.35±0.06 vs. 1.01±0.13, t=-10.307, P<0.001; 0.29±0.05 vs. 1.05±0.18, t=-9.097, P<0.001; 0.54±0.08 vs. 0.98±0.12, t=-6.822, P<0.001; 0.38±0.06 vs. 1.04±0.18, t=-7.778, P<0.001; 0.29±0.04 vs. 1.06±0.12, t=-12.612, P<0.001; 0.36±0.07 vs. 1.06±0.14, t=-10.000, P<0.001; 0.43±0.08 vs. 0.97±0.12, t=-8.372, P<0.001; 0.25±0.03 vs. 1.03±0.12, t=-14.100, P<0.001; 0.19±0.03 vs. 0.99±0.13, t=-13.408, P<0.001). The mRNA expression of E-cadherin was significantly higher than that in NC-siRNA group (2.88±0.42 vs. 0.98±0.12, t=9.726, P<0.001). Conclusion Knockdown of Stat5 inhibits the invasion and EMT of thyroid carcinoma TT cells. Key words: Thyroid neoplasms; Neoplasm invasiveness; Signal transducer and activator of transcription 5; Epithelial mesenchymal transition

DDR2 controls the epithelial-mesenchymal-transition-related gene expression via c-Myb acetylation upon matrix stiffening

Increasing matrix stiffness caused by the extracellular matrix (ECM) deposition surrounding cancer cells is accompanied by epithelial–mesenchymal transition (EMT). Here, we show that expression levels of EMT marker genes along with discoidin domain receptor 2 (DDR2) can increase upon matrix stiffening. DDR2 silencing by short hairpin RNA downregulated EMT markers. Promoter analysis and chromatin immunoprecipitation revealed that c-Myb and LEF1 may be responsible for DDR2 induction during cell culture on a stiff matrix. Mechanistically, c-Myb acetylation by p300, which is upregulated on the stiff matrix, seems to be necessary for the c-Myb-and-LEF1–mediated DDR2 expression. Finally, we found that the c-Myb–DDR2 axis is crucial for lung cancer cell line proliferation and expression of EMT marker genes in a stiff environment. Thus, our results suggest that DDR2 regulation by p300 expression and/or c-Myb acetylation upon matrix stiffening may be necessary for regulation of EMT and invasiveness of lung cancer cells.

Abstract 861: Olfactomedin 4 downregulation is associated with enhancing epithelial-mesenchymal transition in human benign prostate cells and prostate cancer cells

Abstract We have previously reported that lost or reduced olfactomedin 4 (OLFM4) expression is caused by deletions within the OLFM4 gene in 10-25% of all human prostate-cancer samples, and that its expression is lost in more than 58% of advanced prostate-cancer samples. Therefore, we sought to study the role of epigenetic factors in the regulation of OLFM4 gene expression in normal prostate, as well as prostate-cancer, cell lines. Pyrosequencing of genomic DNA extracted from normal prostate or prostate-cancer tissue cells demonstrated that three of the eight CpG sites in the OLFM4 gene promoter were significantly hypermethylated in prostate cancer compared with normal tissue. Exposure to the methylation inhibitor 5-azadeoxycytidine (5-Aza 5 μM) significantly increased OLFM4 expression in RWPE1 benign prostate cells. Knockdown of OLFM4 expression in RWPE benign prostate cells reduced autophagy and enhanced the epithelial-mesenchymal transition (EMT). Restoration of OLFM4 expression in metastatic prostate-cancer cells lacking OLFM4 inhibited cell growth in both in vitro culture models and an in vivo xenograft tumor model, and also inhibited EMT marker gene expression in these cells. 5-Aza induced OLFM4 expression in PC-3 prostate cancer cells and OLFM4 shRNA transfected PC-3 cells affects 5-Aza mediated cell proliferation compared to control-shRNA transfected PC-3 cells. Taken together, our results suggest that OLFM4 inhibits the EMT program in both normal prostate and prostate-cancer cells, and may play a critical role in regulating the EMT program during the progression of cancer. They also suggest that modulation of OLFM4 expression might be a novel molecular target for advancing prostate-cancer therapies. Citation Format: Hongzhen Li, Wenli Liu, Jianqiong Zhu, Kay Chin, Jaime Rodriguez-Canales, Griffin P. Rodgers. Olfactomedin 4 downregulation is associated with enhancing epithelial-mesenchymal transition in human benign prostate cells and prostate cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 861. doi:10.1158/1538-7445.AM2017-861

Involvement of DNMT 3B promotes epithelial-mesenchymal transition and gene expression profile of invasive head and neck squamous cell carcinomas cell lines

BackgroundThe 5-year overall survival rates for head and neck cancer (HNC) relies on distant metastasis. Importantly, the epithelial-mesenchymal transition (EMT) is believed to be an initial step of metastasis. However, the relationship of epigenetic with EMT formation is still unexplored in HNC. This study focuses on invasive subclones of HNC cell lines through the simulation of invasion in vitro; and underlying mechanisms were analyzed including DNA methylation and gene expression profile.MethodsInvasive subclones of NHC cell lines were successfully obtained using transwell coated with Matrixgel. Cells invaded through 8 μm pore several times were subcultured and examined with EMT features including morphology, EMT marker genes expression, and invasive ability. Moreover, compared the profile of genes expression in parental and invasive cells was analyzed using mRNA expression array.ResultsDNA methyltransferase 3B (DNMT 3B) was upregulated in invasive subclones and might control the 5′ region of E-cadherin (E-cad) methylation and further inhibited E-cad protein expression. Interference of DNMT 3B by siRNA or miRNA 29b could reduce EMT and cell invasion. Expression array analysis revealed the most possible involved pathways in cell invasion including arginine and proline metabolism, TGF-beta, and focal adhesion.ConclusionsDNMT 3B might control EMT by DNA methylation manner in invasive HNC cell lines. Moreover, miR-29b mimic downregulated DNMT 3B and inhibited EMT and cell invasion indicated the role of therapeutic agent for invasive HNC. Genes identified from array data and new molecules are involved in metastasis of HNC need further validation.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2468-x) contains supplementary material, which is available to authorized users.

CDH1 (E-cadherin) expression independently affects clinical outcome in acute myeloid leukemia with normal cytogenetics.

Epithelial-mesenchymal transition (EMT) is a critical process which involves in tumor metastasis. As an important EMT marker gene, CDH1 (E-cadherin) expression and its clinical implication in acute myeloid leukemia (AML) remain largely elusive. Real-time quantitative PCR (RQ-PCR) was carried out to examine CDH1 transcript level in 123 de novo AML patients and 34 controls. Compared with controls, CDH1 was significantly downregulated in AML (p<0.001). The median level of CDH1 expression divided total AML patients into CDH1 low-expressed (CDH11ow) and CDH1 high-expressed (CDH1high) groups. There were no significant differences between the two groups in age, peripheral blood cell counts, complete remission (CR) rate, and the distribution of FAB/WHO subtypes as well as karyotypes/karyotypic classifications (p>0.05). However, CDH11ow group tended to have a higher bone marrow (BM) blasts (p=0.093). The spearman correlation analysis further illustrated a trend towards a negative correlation between CDH1 expression level and BM blasts (r=-0.214, p=0.052). CDH1low group had a tendency towards a lower frequency of N/K-RAS mutations (p=0.094). Furthermore, CDH1low patients had markedly shorter overall survival (OS) time in cytogenetic normal AML (CN-AML) (p=0.019). Both univariate and multivariate analyses confirmed the prognostic value of CDH1 expression in CN-AML patients (p=0.027 and 0.033, respectively). CDH1 downregulation acted as an independent prognostic biomarker in CN-AML patients.