上皮—间质转化及其在鼻咽癌中的作用研究进展

鼻咽癌（NPC）是一种与Epstein-Barr病毒（EBV）感染密切相关的鼻咽部黏膜上皮恶性肿瘤，对放疗较敏感，但大多数患者在初次确诊时已有局部淋巴结或远处转移，处于临床Ⅲ或Ⅳ期，晚期患者放疗后仍有30％～40％发生远距离转移和局部复发旧j，侵袭和转移仍是威胁患者生存的关键因素之一。上皮一间质转化（EMT）是肿瘤发生侵袭转移的重要机制，且与NPC原位侵袭和远处转移密切相关。现将EMT在NPC中的作用研究进展综述如下。

基于网络药理学探讨葛根芩连汤治疗肾纤维化的潜在作用

目的 通过网络药理学结合体外细胞实验探究葛根芩连汤治疗肾纤维化的潜在作用。方法 借助本草组鉴(HERB)、 PubChem数据库、 SwissADME平台及SwissTargetPrediction数据库获取葛根芩连汤的主要活性成分及作用靶点,利用DisGenet数据库获得肾脏纤维化相关的靶点基因。同时通过蛋白质免疫印迹法(WB)检测TGF-β1表达。利用RT-qPCR法检测Bcl-2、 STAT3和FN1表达。结果 筛选并得到葛根芩连汤与肾纤维化的共同作用靶点157个。GO/KEGG富集分析筛选GeneRatio在前15名的细胞成分、生物过程、分子功能和信号通路,这些靶点主要参与各种氧化应激反应,并通过MAPK信号通路和P13K-Akt信号通路调控细胞增殖和凋亡。体外实验证明葛根芩连汤含药血清干预可降低TGF-β1诱导HK-2细胞TGF-β1、 STAT3和FN1的表达,同时提高Bcl-2的表达水平。结论 葛根芩连汤改善肾脏纤维化可能与抑制TGF-β的表达以减少EMT发生,同时通过上调凋亡相关基因Bcl-2的表达、抑制STAT3的表达从而阻断细胞凋亡以减轻或逆转炎症状态有关。

CDK8 Promotes Cell Proliferation, Migration and Invasion in Esophageal Squamous Cell Carcinoma Through JAK/ STAT3/EMT Pathway

Objective To investigate the expression of cyclin-dependent kinase 8(CDK8)in esophageal squamous cell carcinoma(ESCC)and its effect on ESCC cells,and to explore its potential molecular mechanism.Methods The expression level of CDK8 mRNA was analyzed using UALCAN database,and then the expression level of CDK8 protein in tumor tissues of ESCC patients was detected by immunohistochemistry(IHC).Esophageal cancer cell lines Kyse-30 and Kyse-150 were stably transfected with lentivirus to achieve knockdown and overexpression of CDK8.EdU proliferation assay,cell colony formation assay,cell cycle assay,cell scratch assay and invasion assay were used to explore the effect of CDK8 protein expression level on the phenotype of ESCC cells.Subsequently,the effect of CDK8 on the growth of esophageal cancer xenografts in vitro was observed by subcutaneous tumor formation assay in mice.Finally,the expression of proliferation and metastasis related proteins was detected by Western blot.Results CDK8 showed high transcription and protein expression levels in ESCC tissues compared with normal esophageal tissues.Knockdown of CDK8 expression significantly inhibited the proliferation,migration and invasion of ESCC cells.In addition,inhibition of CDK8 expression significantly affected the JAK2/STAT3 pathway and the expression of E-cadherin/N-cadherin,while overexpression of CDK8 reversed these effects.Inhibition of STAT3 pathway reversed the promoting effect of CDK8 overexpression on ESCC cell phenotype.Conclusion CDK8 is a cancer-promoting factor of ESCC,which mediates the phosphorylation of JAK2/STAT3 and epithelial-mesenchymal transition(EMT).

Epithelial-mesenchymal transition and cancermetastasis

Epithelial-mesenchymal transition （EMT） is initially considered as a physiological phenomenon during the embryogenesis of mammals, as well as a basic biological event maintaining the stability of the vital body. Recent researches indicated that EMT plays a critical role in various tumors progression, through which epithelial cancers invade and metastasize. The cell characteristics are changed during EMT, in which the cells lose cell-cell and cell-matrix interactions and apical polarity, reorganize their cytoskeleton, and become isolated, motile, as well as resistant to anoikis, then become spindle-shaped mesenchymal cells. This review lays emphasis on studying the cell morphogenesis, makers and molecular mechanism regulation about EMT, discussing the relationship between the EMT and the cancer development and metastasis.

Targeting of RhoE inhibits epithelial-mesenchymal transition during colorectal cancer cell migration

Objective Despite microRNA （miR-200b） being proved to promote the proliferation of colorectal cancer （CRC） cells, the relationship between miR-200b and epithelial-mesenchymal transition （EMT） of CRC cells remains poorly understood. The aim of the study was to investigate the relationship between miR-200b and EMT during CRC cell migration. Methods The effect of miR-200b on EMT-associated markers E-cadherin and vimentin was evaluated by western blot in CRC cells （SW620 and HT-29） by treatment with miR-200b mimics and inhibitors. A lucifer- ase reporter assay was employed to detect downstream targets of miR-200b. Transwell migration assays were used to detect CRC cell migration. Results Westem blots revealed that treatment with miR-200b mimics led to up-regulation of E-cadherin and down-regulation of vimentin, metalloproteinase （MMP）-9, and MMP-2, whereas treatment with miR- 200b inhibitor exhibited opposite effects on expression of E-cadherin and vimentin. Luciferase reporter assays demonstrated that RhoE （RND3） was targeted by miR-200b. Two predicted target sites of miR-200b were present in the 3＇-UTR of RhoE. Predicted target site 1 was from nucleotides 1584 to 1591, and site 2 was from nucleotides 1729 to 1735. RhoE knockdown cell lines were also established to investigate the impact of RhoE and miR-200b on EMT and cell migration. RhoE knockdown enhanced the effect of miR- 200b mimics, up-regulating E-cadherin and down-regulating vimentin. RhoE knockdown also inhibited cell migration. Furthermore, miR-200b mimic treatment further promoted the inhibitory effect of RhoE knock- down on cell migration.

Induction of epithelial-mesenchymal transition (EMT) in human hepatocellular carcinoma after radiotherapy

Objective: Epithelial-mesenchymal transition (EMT) is a critical early event for the invasion and metastasis of many carcinomas. In the present study, we examined EMT markers in the residual cancer cells of hepatocellular carcinoma (HCC) after radiotherapy. Methods: Eight patients with large HCC who underwent hepatectomy with preoperative radiothera- py were studied. The expressions of E-cadherin and vimentin were determined immunohistochemically in the residual cancer cells of HCC following radiotherapy, and also in the pre-radiotherapy biopsy cancer cells. Results: Histological analysis showed that some residual cancer cells of HCC displayed an elongated spindle or fibroblast-like shape. The expression of E- cadherin was markedly reduced or negative in the spindle residual cancer cells, but the expression of vimentin significantly in- duced. However, the above changes were not found in the pre-radiotherapy biopsy cancer cells. Conclusion: EMT is induced in the residual cancer cells of HCC following radiotherapy, which may facilitate the systemic dissemination of cancer cells.

Relationship between epithelial to mesenchymaltransition and chemoresistance of lung cancer

Objective： The aim of this study was to explore the correlation between epithelial to mesenchymal transition （EMT） and chemoresistance of non-small-cell lung cancer （NSCLC）. Methods： In vitro, the drug resistance index of cisplatin resistant lung adenocarcinoma cell line （A549/DDP） was detected by CCK-8 assay; the morphological change between A549/ DDP cells and lung adenocarcinoma cells （A549） was observed by phase contrast microscope; expression of EMT markers （including E-cadherin and vimentin） and resistance protein, excision repair cross-complementing 1 （ERCC1） was detected by immunocytochemistry. The expression of E-cadherin, vimentin and ERCC1 was investigated by immunohistochemistry in 120 cases of NSCLC, half of that were treated with pre-operative neoadjuvant chemotherapy （neoadjuvant chemotherapy group）, and the other underwent surgery alone （simple surgery group）. Results： There was a significant difference between the ICso （half maximal inhibitory concentration） of A549/DDP cells （5.20） and A549 cells （1.88） （P 〈 0.05）, and the drug resistance index of A549/DDP cells was 2.77. Compared with A549 cells, A549/DDP cells increased expression of ERCC1 （P 〈 0.05）. Moreover, A549/DDP cells showed morphological and phenotypic changes consistent with EMT： with spindle-shaped morphology, and decreased expression of E-cadherin and increased expression of vimentin. Immunohistochemistry showed significant positive correlation between the expression of ERCCI and vimentin （r = 0.496, 0.332, P 〈 0.05）, and significant negative correlation between the ERCCI and E-cadherin （r = -0.403, -0.295, P 〈 0.05） in neoadjuvant chemotherapy group and simple surgery group. In addition, compared with simple surgery group, the expression of ERCC1 （P = 0.003） and vimentin （P = 0.004） was significantly increased, and the expression of E-cadherin was decreased in neoadjuvant chemotherapy group （P = 0.032）. Cenclusion： A549/DDP cells acquired cisplatin-resistance and occurred EMT simultaneously; the phenomenon of chemoresistance and EMT was caused more easily in neoadjuvant chemotherapy group. As such, we further confirmed the close correlation between chemoresistance and EMT of NSCLC, and provided theoretical basis for the targeting therapy with EMT regulatory factor for chemoresistant NSCLC patients.

二甲双胍对高葡萄糖环境下结肠癌细胞增殖和侵袭的影响

目的观察二甲双胍在高葡萄糖环境下对人结肠癌细胞系SW480增殖和侵袭的影响,并探讨其可能的机制。方法通过Western blot方法检测SW480细胞在高葡萄糖及不同浓度二甲双胍干预后E-cadherin和Vimentin的表达水平,并应用CCK-8法及Transwell侵袭实验检测细胞增殖及侵袭能力的变化。结果高葡萄糖作用不同时间后均能促进结肠癌细胞增殖,二甲双胍能抑制结肠癌细胞的增殖,并呈时间——剂量依赖性。20 mmol/L浓度二甲双胍干预48 h后,Transwell侵袭实验结果显示细胞穿膜数为(40.18±2.22)%,明显低于高糖组和对照组(F=49.403,P<0.001);Western blot结果显示E-cadherin表达明显增强,Vimentin表达明显减弱。结论高葡萄糖环境能促进结肠癌细胞生长,二甲双胍能明显抑制有或无高葡萄糖环境下结肠癌的增殖和侵袭能力,其机制可能与调节上皮——间质转化(EMT)过程有关。

Cyclooxygenase-2 promotes ovarian cancer cell migration and cisplatin resistance via regulating epithelial mesenchymal transition

Objective: Drug-resistance and metastasis are major reasons for the high mortality of ovarian cancer(OC) patients. Cyclooxygenase-2(COX-2) plays a critical role in OC development. This study was designed to evaluate the effects of COX-2 on migration and cisplatin(cis-dichloro diammine platinum, CDDP) resistance of OC cells and explore its related mechanisms. Methods: Cell counting kit-8(CCK-8) assay was used to detect the cytotoxicity effects of celecoxib(CXB) and CDDP on SKOV3 and ES2 cells. The effect of COX-2 on migration was evaluated via the healing test. Western blot and real-time quantitative polymerase chain reaction(q PCR) were used to analyze E-cadherin, vimentin, Snail, and Slug levels. Results: COX-2 promoted drug-resistance and cell migration. CXB inhibited these effects. The combination of CDDP and CXB increased tumor cell sensitivity, reduced the amount of CDDP required, and shortened treatment administration time. COX-2 upregulation increased the expression of Snail and Slug, resulting in E-cadherin expression downregulation and vimentin upregulation. Conclusions: COX-2 promotes cancer cell migration and CDDP resistance and may serve as a potential target for curing OC.

SMAD7 and SERPINE1 as novel dynamic network biomarkers detect and regulate the tipping point of TGF-beta induced EMT

Epithelial–mesenchymal transition(EMT) is a complex nonlinear biological process that plays essential roles in fundamental biological processes such as embryogenesis, wounding healing, tissue regeneration,and cancer metastasis. A hallmark of EMT is the switch-like behavior during state transition, which is characteristic of phase transitions. Hence, detecting the tipping point just before mesenchymal state transition is critical for understanding molecular mechanism of EMT. Through dynamic network biomarkers(DNB) model, a DNB group with 37 genes was identified which can provide the early-warning signals of EMT. Particularly, we found that two DNB genes, i.e., SMAD7 and SERPINE1 promoted EMT by switching their regulatory network which was further validated by biological experiments. Survival analyses revealed that SMAD7 and SERPINE1 as DNB genes further acted as prognostic biomarkers for lung adenocarcinoma.

Epigenetic and metabolic regulation of breast cancer stem cells

Breast cancer has a relatively high mortality rate in women due to recurrence and metastasis. Increasing evidence has identified a rare population of cells with stem cell-like properties in breast cancer. These cells, termed cancer stem cells （CSCs）, which have the capacity for self-renewal and differentiation, contribute significantly to tumor progression, recurrence, drug resistance and metastasis. Clarifying the mechanisms regulating breast CSCs has important implications for our understanding of breast cancer progression and therapeutics. A strong connection has been found between breast CSCs and epithelial mesenchymal transition （EMT）. In addition, recent studies suggest that the maintenance of the breast CSC phenotype is associated with epigenetic and metabolic regulation. In this review, we focus on recent discoveries about the connection between EMT and CSC, and advances made in under- standing the roles and mechanisms of epigenetic and metabolic reprogramming in controlling breast CSC properties.

Effect of Tangnaikang on TGF-β_1-induced transdifferentiation of human renal tubular epithelial HK-2 cells

OBJECTIVE： To explore the function of Tangnai- kang （TNK） in the prevention and treatment of re- nal interstitial fibrosis through transdifferentiation of the human renal tubular epithelial cell line HK-2 induced bytransforming growth factor-β1 （TGF-β1）. METHODS： HK-2 cells cultured in dulbecco＇s modi- fied eagle medium/F12 （1：1） with 10% fetal calf se- rum were divided into six groups： blank control group, TGF-β1 group （TGF-β1 10 ng/mL）, serum con- trol group （TGF-β1 10 ng/mL ＋ 10% serum）, treat- ment group 1 （TGF-β1 10 ng/mL ＋ 5% TNK serum）, treatment group 2 （TGF-β1 10 ng/mL＋10% TNK se-rum）, and treatment group 3 （TGF-β1 10 ng/mL＋ 20% TNK serum）. Cell proliferation was detected by 4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetrazoliu m bromide assay. Expression of a-smooth muscle ac- tin （a-SMA） and E-cadherin were observed by im- munohistochemical assay. The contents of collagen Ⅰ （Col Ⅰ）, collagen Ⅲ（ColⅢ）, and fibronectin （FN） in the culture medium supernatant were detected by ELISA. RESULTS： E-cadherin was expressed and α-SMA was not expressed in normal HK-2 cells. In HK-2 cells cultured with TGF-β1, α-SMA expression signifi- cantly increased, HK-2 cells significantly proliferat- ed, and secretion of Col Ⅰ, Col Ⅲ, and FN significantly increased compared with the blank control group （all P〈0.05）. In the HK-2 cells cultured with TGF-β1 and TNK serum, the expression of α-SMA signifi- cantly decreased, the expression of E-cadherin sig- nificantly increased, and the cell proliferation and the secretion of Col Ⅰ, Col Ⅲ and FN were significant- ly inhibited compared with the TGF-β1 group （all P〈 0.05. CONCLUSION： TNK can inhibit cell proliferation and reduce secretion of Col Ⅰ, Col Ⅲ, and FN.This in- dicates that TNK can inhibit transdifferentiation of human renal tubular epithelial cells induced by TGF-β1, with the effect of preventing and treating renal interstitial fibrosis.