High expression of NEDD9 predicts adverse outcomes of colorectal cancer patients

NEDD9, a member of Crk-associated substrate (CAS) family, is highly expressed in multiple cancer types and involved cancer cell adhesion, migration, invasion. The prognostic value of NEDD9 has not been evaluated before. The aim of this study was to evaluate the association between NEDD9 expression and survival in colorectal cancer (CRC) patients. NEDD9 expression was analyzed by immunohistochemistry in 92 patients with CRC. Patients were followed-up annually by telephone or at outpatient clinic. The results revealed that high expression of NEDD9 in 68/92 CRC samples, compared with 12/92 normal tissues (P<0.01). Correlation analysis showed high level of expression of NEDD9 was significantly correlated with advanced TNM stage (P=0.014), pT grade (P=0.009), pN (P=0.013) and pM status (P=0.047). Patients with a higher NEDD9 expression had a significantly shorter overall survival (OS) (P<0.01). The multivariate analysis revealed that NEDD9 expression could serve as an independent predictive factor of OS. Our finding demonstrated the potential value of NEDD9 expression level as a prognostic molecular marker and a target for new therapies for CRC patients.     

Genetic ablation of FLRT3 reveals a novel morphogenetic function for the anterior visceral endoderm in suppressing mesoderm differentiation

During early mouse development, the anterior visceral endoderm (AVE) secretes inhibitor and activator signals that are essential for establishing the anterior–posterior (AP) axis of the embryo and for restricting mesoderm formation to the posterior epiblast in the primitive streak (PS) region. Here we show that AVE cells have an additional morphogenetic function. These cells express the transmembrane protein FLRT3. Genetic ablation of FLRT3 did not affect the signaling functions of the AVE according to the normal expression pattern of Nodal and Wnt and the establishment of a proper AP patterning in the epiblast. However, FLRT3^−/− embryos showed a highly disorganized basement membrane (BM) in the AVE region. Subsequently, adjacent anterior epiblast cells displayed an epithelial-to-mesenchymal transition (EMT)-like process characterized by the loss of cell polarity, cell ingression, and the up-regulation of the EMT and the mesodermal marker genes Eomes, Brachyury/T, and FGF8. These results suggest that the AVE acts as a morphogenetic boundary to prevent EMT and mesoderm induction in the anterior epiblast by maintaining the integrity of the BM. We propose that this novel function cooperates with the signaling activities of the AVE to restrict EMT and mesoderm induction to the posterior epiblast.     

ATAD2对人胶质瘤细胞系转移及上皮间质转换的影响

目的探讨三磷酸腺苷酶家族蛋白2(ATAD2)对人胶质瘤细胞的影响。方法用real-time PCR及Western blot检测ATAD2在人胶质瘤细胞系U87MG、U251和正常人星形胶质细胞的表达。U87MG和U251分为对照组(control)、脂质体对照组(mock)、ATAD2 siRNA(转染特异性siRNA)和ATAD2 overexpression(过表达ATAD2)4组,MTT法、Transwell实验观察细胞增殖和侵袭迁移。Western blot检测上皮间质转换标志蛋白上皮钙黏素、神经钙黏素和波形蛋白的表达。结果 U87MG和U251细胞ATAD2高表达。与对照相比,ATAD2 siRNA抑制U87MG和U251细胞增殖、侵袭、迁移、神经钙黏素及波形蛋白表达,促进上皮钙黏素表达(P0.05);ATAD2 overexpression促进细胞增殖、侵袭、迁移、神经钙黏素和波形蛋白表达,降低上皮钙黏素表达(P0.05)。结论 ATAD2可能通过调节上皮间充质转换进程参与人胶质瘤细胞转移。     

miR-183 promotes radioresistance of lung adenocarcinoma H1299 cells via epithelial-mesenchymal transition

Lung adenocarcinomas are usually sensitive to radiation therapy, but some develop resistance. Radiation resistance can lead to poor patient prognosis. Studies have shown that lung adenocarcinoma cells (H1299 cells) can develop radioresistance through epithelial-mesenchymal transition (EMT), and this process is regulated by miRNAs. However, it is unclear which miRNAs are involved in the process of EMT. In our present study, we found that miR-183 expression was increased in a radioresistant lung adenocarcinoma cell line (H1299R cells). We then explored the regulatory mechanism of miR-183 and found that it may be involved in the regulation of zinc finger E-box-binding homeobox 1 (ZEB1) expression and mediate EMT in lung adenocarcinoma cells. qPCR results showed that miR-183, ZEB1, and vimentin were highly expressed in H1299R cells, whereas no difference was observed in E-cadherin expression. Western blot results showed that ZEB1 and vimentin were highly expressed in H1299R cells, while E-cadherin expression was decreased. When miR-183 expression was inhibited in H1299R cells, radiation resistance, proliferation, and cell migration were decreased. The expression of ZEB1 and vimentin in H1299R cells was decreased, while the expression of E-cadherin was increased. Moreover, miR-183 overexpression in H1299 cells enhanced radiation resistance, proliferative capacity, and cell migration ability. The expression of ZEB1 and vimentin in H1299 cells was increased, while that of E-cadherin was decreased. In conclusion, miR-183 may promote EMT and radioresistance in H1299 cells, and targeting the miR-183-ZEB1 signaling pathway may be a promising approach for lung cancer treatment.     

Invasive prostate cancer cells are tumor initiating cells that have a stem cell-like genomic signature

Development of metastasis is a leading cause of cancer-induced death. Acquisition of an invasive tumor cell phenotype suggests loss of cell adhesion and basement membrane breakdown during a process termed epithelial-to-mesenchymal transition (EMT). Recently, cancer stem cells (CSC) were discovered to mediate solid tumor initiation and progression. Prostate CSCs are a subpopulation of CD44⁺ cells within the tumor that give rise to differentiated tumor cells and also self-renew. Using both primary and established prostate cancer cell lines, we tested the assumption that CSCs are more invasive. The ability of unsorted cells and CD44-positve and -negative subpopulations to undergo Matrigel invasion and EMT was evaluated, and the gene expression profiles of these cells were analyzed by microarray and a subset confirmed using QRT-PCR. Our data reveal that a subpopulation of CD44⁺ CSC-like cells invade Matrigel through an EMT, while in contrast, CD44⁻ cells are non-invasive. Furthermore, the genomic profile of the invasive cells closely resembles that of CD44⁺CD24⁻ prostate CSCs and shows evidence for increased Hedgehog signaling. Finally, invasive cells from DU145 and primary prostate cancer cells are more tumorigenic in NOD/SCID mice compared with non-invasive cells. Our data strongly suggest that basement membrane invasion, an early and necessary step in metastasis development, is mediated by these potential cancer stem cells. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Livin通过Akt信号途径促进胃癌SGC7901细胞的上皮细胞间质转换

目的探讨胃癌SGC7901细胞中Livin基因的表达对细胞上皮细胞间质转换(EMT)的影响。方法用Livin基因的shRNA慢病毒感染胃癌SGC7901细胞,筛选稳定沉默的细胞株,Transwell检测细胞的侵袭能力,细胞划痕实验检测细胞迁移能力,Western blot检测E-cadherin和vimentin表达,同时检测Akt信号通路的激活状态。结果沉默Livin基因后,胃癌SGC7901细胞侵袭迁移能力明显降低(P0.05),E-cadherin明显上调,vimentin则明显下调(P0.05),同时明显抑制Akt信号通路信号的激活(P0.05)。结论 Livin能够通过激活Akt信号通路从而诱导SGC7901细胞发生EMT,从而促进肿瘤细胞体外侵袭及迁移能力。     

Connective tissue growth factor induces renal fibrosis via epidermal growth factor receptor activation

Connective tissue growth factor (CCN2/CTGF) is a matricellular protein that is overexpressed in progressive human renal diseases, mainly in fibrotic areas. In vitro studies have demonstrated that CCN2 regulates the production of extracellular matrix (ECM) proteins and epithelial–mesenchymal transition (EMT), and could therefore contribute to renal fibrosis. CCN2 blockade ameliorates experimental renal damage, including diminution of ECM accumulation. We have reported that CCN2 and its C‐terminal degradation product CCN2(IV) bind to epidermal growth factor receptor (EGFR) to modulate renal inflammation. However, the receptor involved in CCN2 profibrotic actions has not been described so far. Using a murine model of systemic administration of CCN2(IV), we have unveiled a fibrotic response in the kidney that was diminished by EGFR blockade. Additionally, in conditional CCN2 knockout mice, renal fibrosis elicited by folic acid‐induced renal damage was prevented, and this was linked to inhibition of EGFR pathway activation. Our in vitro studies demonstrated a direct effect of CCN2 via the EGFR pathway on ECM production by fibroblasts and the induction of EMT in tubular epithelial cells. Our studies clearly show that the EGFR regulates CCN2 fibrotic signalling in the kidney, and suggest that EGFR pathway blockade could be a potential therapeutic option to block CCN2‐mediated profibrotic effects in renal diseases. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.