结缔组织生长因子在肝细胞上皮-间充质转分化及肝纤维化形成中的作用研究进展

纤维化是器官（肝、肾、肺等）慢性功能衰竭的一个共同机制，目前尚无有效防治方法。对上皮-间充质转分化（epithelial—to—mesenchymaltransition，EMT）的研究使人们对器官纤维化的传统认识受到挑战，逆转分化已被认为是未来抗肝纤维化治疗的重要策略之一。

Hyperthermia inhibits hypoxia-induced epithelial-mesenchymal transition in HepG2 hepatocellular carcinoma cells

AIM:To investigate the effect of hyperthermia on hy-poxia-induced epithelial-mesenchymal transition (EMT) in HepG2 hepatocellular carcinoma (HCC) cells, and its mechanism. METHODS:Cells were treated with hyperthermia at 43 ℃ for 0.5 h, followed by incubation under hypoxic or normoxic conditions for 72 h. Cell morphology was observed. Expressions of E-cadherin and vimentin were determined by immunofluorescence assay or Western blot. The protein and mRNA expressions of Snail were also determined by Western blot and reverse transcrip-tion-polymerase chain reaction. Cell migratory capacity was evaluated. RESULTS:Hypoxia induced EMT in HepG2 cells, which was evidenced by morphological, molecular and func-tional changes, including the formation of a spindle shape and the loss of cell contact. The expression of E-cadherin was decreased but the expression of vimentin was increased; also, the migratory capability was increased by 2.2 ± 0.20-fold as compared with normoxia. However, those effects were inhibited by hyperthermia pretreatment. Furthermore, protein synthesis and mRNA expression of Snail in the cells were enhanced by hy-poxia as compared with normoxia, and also significantly inhibited by hyperthermia pretreatment. CONCLUSION:Hyperthermia may inhibit hypoxia-induced EMT in HepG2 HCC cells, and the mechanism may involve inhibition of induced expression of Snail.

Doublecortin and CaM kinase-like-1 as an independent prognostic factor in patients with resected pancreatic carcinoma

To elucidate the effect of expression of doublecortin and CaM kinase-like-1 (DCLK1) in patients with pancreatic ductal adenocarcinoma (PDAC). METHODSTumor specimens were obtained from 136 patients with pancreatic cancer who had undergone resection without preoperative therapy between January 2000 and December 2013 at the Department of Surgical Oncology, Osaka City University. The resected specimens were analyzed for associations with clinicopathological data, including DCLK1 expression, epithelial mesenchymal transition (EMT) marker expression, and cancer stem cell (CSC) marker expression. Univariate and multivariate survival analyses were performed and we assessed the association between DCLK1 expression and clinicopathological factors, including the EMT marker and CSC marker. RESULTSIn total, 48.5% (66/136) of the pancreatic cancer samples were positive for DCLK1. Patients with DCLK1-positive tumors had significantly shorter survival times than those with DCLK1-negative tumors (median, 18.7 mo vs 49.5 mo, respectively; P < 0.0001). Positive DCLK1 expression correlated with histological grade (P = 0.0290), preoperative CA19-9 level (P = 0.0060), epithelial cell adhesion molecule (EpCAM) expression (P = 0.0235), and the triple-positive expression of CD44/CD24/EpCAM (P = 0.0139). On univariate survival analysis, five factors were significantly associated with worse overall survival: histological grade of G2 to G4 (P = 0.0091), high preoperative serum SPan-1 level (P = 0.0034), R1/2 (P < 0.0001), positive expression of DCLK1 (P < 0.0001) or CD44 (P = 0.0245). On multivariate survival analysis, R1/2 [odds ratio (OR) = 2.019, 95% confidence interval (CI): 1.380-2.933; P = 0.0004] and positive DCLK1 expression (OR = 1.848, 95%CI: 1.2854-2.661; P = 0.0009) were independent prognostic factors. CONCLUSIONDCLK1 expression was found to be an independent prognostic factor and it may play a crucial prognostic role by promoting acquisition of stemness.

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.

Implication of the Hedgehog pathway in hepatocellular carcinoma

The prognosis for patients who are diagnosed with advanced stage hepatocellular carcinoma(HCC)is poor because there are few treatment options.Recent research has focused on the identification of novel molecular entities that can be targeted to inhibit oncogenic signals that are involved in the carcinogenesis,proliferation and progression of HCC.Among all of the pathways that are involved in the development of HCC,Hedgehog(HH)signalling has demonstrated a substantial role in hepatocarcinogenesis and HCC progression.HH plays a physiological role in embryogenesis,through the induction of the differentiation of hepatocytes from endodermal progenitors.The re-activation of the HH pathway in chronic damaged liver is a mechanism of fibrotic degeneration and is implicated in various stages of HCC development.HH activation sustains the subpopulation of immature liver epithelial cells that are involved in the pathogenesis of cirrhosis and HCC,and HH itself is a mediator of the alcohol-derived malignant transformation of liver cells.High levels of expression of HH protein markers in liver tumour tissues are correlated with aggressive histological and biological features and a poor clinical outcome.In vitro and in vivo inhibition models of the HH pathway confirm that HH is essential in maintaining tumour growth,metastasis and a mesenchymal phenotype.

Cullin 4A is associated with epithelial to mesenchymal transition and poor prognosis in perihilar cholangiocarcinoma

AIM To explore the functional role of cullin 4A(CUL4A), a core subunit of E3 ubiquitin ligase, in perihilar cholangiocarcinoma(PHCC).METHODS The expression of CUL4 A in PHCC cell lines was evaluated by Western blot and quantitative reverse transcription-polymerase chain reaction. Immunohistochemistry(IHC) was adopted to investigate the relationship between CUL4 A expression and clinicopathological characteristics of PHCC. Univariate analysis and multivariate regression analysis were performed to analyze the risk factors related to overall survival(OS) and progression-free survival(PFS) of PHCC patients. Wound healing, Transwell and Matrigel assays were utilized to explore the function of CUL4 A in PHCC metastasis. Furthermore, expression of epithelial to mesenchymal transition(EMT) markers was verified in cells with CUL4 A knockdown or overexpression. The relationship between CUL4 A expression and E-cadherin expression was also analyzed by IHC assay. Finally, the role of ZEB1 in regulating CUL4 A mediated PHCC was detected by IHC, Western blot, Transwell and Matrigel assays.RESULTS CUL4 A overexpression was detected in PHCC cell lines and clinical specimens. Clinicopathological analysis revealed a close correlation between CUL4 A overexpression and tumour differentiation, T, N and TNM stages in PHCC. Kaplan-Meier analysis revealed that high CUL4 A expression was correlated with poor OS and PFS of PHCC patients. Univariate analysis identified the following four parameters as risk factors related to OS rate of PHCC: T, N, TNM stages and high CUL4 A expression; as well as three related to PFS: N stage, TNM stage and high CUL4 A expression. Further multivariate logistic regression analysis identified high CUL4 A expression as the only independent prognostic factor for PHCC. Moreover, CUL4 A silencing in PHCC cell lines dramatically inhibited metastasis and the EMT. Conversely, CUL4 A overexpression promoted these processes. Mechanistically, ZEB1 was discovered to regulate the function of CUL4 A in promoting the EMT and metastasis.CONCLUSION CUL4 A is an independent prognostic factor for PHCC, and it can promote the EMT by regulating ZEB1 expression. CUL4 A may be a potential therapeutic target for PHCC.

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.

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.

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.

Myeloid-specific expression of Stat3C results in conversion of bone marrow mesenchymal stem cells into alveolar type Ⅱ epithelial cells in the lung

Bone marrow mesenchymal stem cells (BMSCs) and myeloid lineage cells originate from the bone marrow, and influence each other in vivo. To elucidate the mechanism that controls the interrelationship between these two cell types, the signaling path- way of signal transducer and activator of transcription 3 (Stat3) was activated by overexpressing Stat3C in a newly established c-fms-rtTA/(TetO)7-CMV-Stat3C bitransgenic mouse model, In this system, Stat3C-Flag fusion protein was overexpressed in myeloid lineage cells after doxycycline treatment. Stat3C overexpression induced systematic elevation of macrophages and neutrophils in multiple organs. In the lung, tissue neoplastic pneumocyte proliferation was observed. After in vitro cultured hSP-B 1.5-kb lacZ BMSCs were injected into the bitransgenic mice, BMSCs were able to repopulate in multiple organs, self-renew in the bone marrow and spleen, and convert into alveolar type II epithelial cells. The bone marrow transplantation study indicated that increases of myeloid lineage cells and BMSC-AT II cell conversion were due to malfunction of myeloid progenitor cells as a result of Stat3C overexpression. The study supports the concept that activation of the Stat3 pathway in myeloid cells plays an important role in BMSC function, including homing, repopulating and converting into residential AT II epithelial cells in the lung.

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.