Effect of Rapamycin on TGF-β_1-induced epithelial-mesenchymal transition in LoVo colonic adenocarcinoma cells

Objective： To investigate the effect of Rapamycin on epithelial-mesenchymal transition（EMT） of LoVo colonic adenocarcinoma cells in vitro. Methods：Cultured LoVo colonic adenocarcinoma cells were divided into three groups： negative control group, EMT-inducing group（TGF-β1） and EMT-interfering group（TGF-β1 plus Rapamycin）. E-cadherin expression in LoVo cells was detected by Western Blot, while the expression of vimentin was evaluated through immunocytochemistry. The Snail mRNA in LoVo cells was examined by RT- PCR. Results：TGF-β1 induced LoVo cell switching from polygonal to spindle-shaped. TGF-β1 enhanced the expression of vimentin, but lowered the level of E-cadhefin. In contrast, Rapamycin impaired the transition induced by TGF-β1. Rapamycin dramatically abrogated TGF-β1-induced vimentin expression and restored E-cadherin expression in LoVo cells. Rapamycin significantly repressed the upregulation of Snail mRNA expression induced by TGF-β1. Conclusion：Rapamycin dramatically abrogated TGF-β1 induced Snail mRNA expression in LoVo cells, hence inhibiting EMT of these cells in vitro.

Niaoduqing granules inhibits TGF-β1-induced epithelial-mesenchymal transition in human renal tubular epithelial HK-2 cells

Objective Chronic renal failure(CRF)is a worldwide public health burden.Niaoduqing granules(NDQ)is widely used for CRF treatment in China.However,the underlying mechanism of NDQ is not fully studied.This study is aimed to investigate whether NDQ ameliorate CRF by inhibiting transforming growth factor-β1(TGF-β1)-induced EMT in human renal tubular epithelial HK-2 cells.Methods 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylterazolium bromide assay and colony formation assay were used to investigate the cytotoxicity of NDQ in HK-2 cells.Morphological changes of HK-2 cells after TGF-β1 or/and NDQ treatment were observed under a microscope.Wound-healing,migration and invasion assays were performed to determine the cell movement,migratory and invasive abilities,respectively.Western blot analysis was carried out to examine the protein levels of TGF-βreceptor I(TβRI)and epithelial-mesenchymal transition(EMT)-associated factors.Fluorescence confocal microscopy was applied to observe the organization of filamentous actin.Results NDQ suppressed TβRI expression dose-dependently.NDQ inhibited TGF-β1-stimulated EMT in HK-2 cells,supported by the evidences that NDQ prevented morphology change,attenuated cell migration and invasion,downregulated EMT factors and reorganized filamentous actin distribution in TGF-β1-stimulated HK-2 cells.Conclusions NDQ attenuates chronic renal failure which may be associated with inhibition of TβRI expression and EMT process.

Inhibition of Ubiquitin-specific Protease 4 Attenuates Epithelial-Mesenchymal Transition of Renal Tubular Epithelial Cells via Transforming Growth Factor Beta Receptor Type Ⅰ

Objective Ubiquitin-specific protease 4(USP4)facilitates the development of transforming growth factor-beta 1(TGF-β1)-induced epithelial-mesenchymal transition(EMT)in various cancer cells.Moreover,EMT of renal tubular epithelial cells(RTECs)is required for the progression of renal interstitial fibrosis.However,the role of USP4 in EMT of RTECs remains unknown.The present study aimed to explore the effect of USP4 on the EMT of RTECs as well as the involved mechanism.Methods In established unilateral ureteral obstruction(UUO)rats and NRK-52E cells,immunohistochemistry and Western blot assays were performed.Results USP4 expression was increased significantly with obstruction time.In NRK-52E cells stimulated by TGF-β1,USP4 expression was increased in a time-dependent manner.In addition,USP4 silencing with specific siRNA indicated that USP4 protein was suppressed effectively.Meanwhile,USP4 siRNA treatment restored E-cadherin and weakened alpha smooth muscle actin(α-SMA)expression,indicating that USP4 may promote EMT.After treatment with USP4 siRNA and TGF-β1 for 24 h,the expression of TGF-β1 receptor type I(TβRI)was decreased.Conclusion USP4 promotes the EMT of RTECs through upregulating TβRI,thereby facilitating renal interstitial fibrosis.These findings may provide a potential target of USP4 in the treatment of renal fibrosis.

Suspended particulate matter promotes epithelial-to-mesenchymal transition in alveolar epithelial cells via TGF-β1-mediated ROS/IL-8/SMAD3 axis

Epidemiological evidence presents that dust storms are related to respiratory diseases,such as pulmonary fibrosis(PF).However,the precise underlying mechanisms of SPM-elicited adverse effects still need to be investigated.Epithelial-mesenchymal transition(EMT)process is a characteristic of PF.We discussed whether suspended particulate matter(SPM)is involved in EMT induction via transforming growth factor-β1(TGF-β1).In this study,a detailed elemental analysis(55 elements),particle size,and morphology were determined.To investigate the toxicity of SPM,an MTT test was performed to detect cell viability.Next,A549cells were exposed to selected concentrations of SPM(20 and 40μg/mL)for single and repeated exposures.The DCFH-DA assay showed that exposure to SPM could produce reactive oxygen species(ROS).The ELISA assay demonstrated increased levels of interleukin-8(IL-8)and TGF-β1 in the supernatant.Western blot was used to detect the expression of proteins associated with EMT and the SMAD3-dependent pathway.Results of western blot demonstrated that E-cadherin was reduced,whereas p-SMAD3,vimentin,andα-smooth muscle actin were elevated.Our findings indicated that SPM triggered EMT by induction of oxidative stress,inflammation,and the TGF-β1/SMAD3 pathway activation.

Ganoderic acid A ameliorates renalfibrosis by suppressing the expression of NPC1L1

Objective: The study aimed to explore the protective mechanism of Ganoderic acid A (GAA) in renal fibrosisand to verify that GAA can ameliorate renal fibrosis by regulating the Niemann-pick C1-like 1 (NPC1L1) gene. Methods:Transforming growth factor beta1 (TGF-β1) was used to treat Human Kidney-2 (HK-2) cells to establish a renal fibrosismodel. The differentially expressed genes in the control (CTRL) group, TGF-β1 group, and TGF-β1 + GAA group werescreened via transcriptome sequencing technology and verified by qPCR and Western blot experiments. The NPC1L1gene overexpression plasmid was constructed. The expression levels of N-cad, E-cad, and Slug-related proteins inCTRL, TGF-β1, TGF-β1+GAA (25 μg/mL), and TGF-β1+GAA (25 μg/mL) + NPC1L1 Overexpression (OE) groupswere detected by qPCR and Western blot analysis. Western blot analysis was used to identify the extracellular matrixassociated proteins Tenascin-C, α-SMA, and fibrosis-related protein Collagen I. Fibrosis marker protein Fibronectinwas detected and quantified by immunofluorescence. Results: Transcriptomic sequencing revealed that TGF-β1stimulation led to 267 differentially regulated genes, with 118 up-regulated and 149 down-regulated, while furthermodulation of 213 genes, comprising 112 up-regulated and 101 down-regulated genes, was observed in the GAAintervention group. The target gene in these processes was found to be NPC1L1 by investigations using GeneOntology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). qPCR and Western blot resultsconfirmed that TGF-β1 increased NPC1L1 expression, which was attenuated by GAA. Additionally, TGF-β1upregulated N-cad and Slug. However, GAA reversed this effect and NPC1L1 overexpression partially rescued theGAA effect. TGF-β1 also decreased E-cad expression, reversed by GAA, and NPC1L1 overexpression antagonized thisreversal. Furthermore, TGF-β1 promoted Collagen I, α-SMA, and Tenascin-C expression, and GAA reduced theselevels, effects that were reversed by NPC1L1 overexpression. Immunofluorescence results showed that TGF-β1increased fibronectin expression, which was decreased by GAA, and increased by NPC1L1 overexpression.Conclusion: GAA ameliorates renal fibrosis by antagonizing NPC1L1 gene expression inhibiting epithelialmesenchymal transition and reducing extracellular matrix formation.

Expression and significance of E-cadherin,N-cadherin,transforming growth factor-β1 and Twist in prostate cancer

Objective:To study the expression of E-cadherin,N-cadherin,TGF-|3 1 and Twist protein and investigate its significance in the occurrence and development of prostate cancer.Methods:The expression of E-cadherin,N-cadherin,TGF-β1 and Twist protein in 59 prostate cancer tissues and 21 adjacent tissues were detected by immunohistochemical SABC staining,and the correlation with clinicopathological features was analyzed.Results:Positive rates of E-cadherin,N-cadherin,TGF-β1 and Twist were 32.2%,54.2%,71.2%and 74.6%,respectively,in prostate cancer tissues and 85.7%,9.52%,19.0%and 9.52%,respectively,in cancer—adjacent tissues,with significant differences between the two groups(P<0.05).The reduced expression of E-cadherin was related to the differentiation of prostate cancer tissues and PSA level,but was not associated with clinical stage,lymph node metastasis,bony metastasis and age.The increased expression of N-cadherin,TGF-β1 and Twist was related to the differentiation of prostate cancer tissues,clinical stage,lymph node metastasis,bony metastasis,but not to age.The difference in positive expression of N-cadherin and TGF-β1 was significant between PSA≤20μg/L group and PSA>20μg/L group,but the positive expression of Twist was not significant between groups.The expression of E-cadherin was highly negatively correlated with that of N-cadherin and also highly negatively correlated with that of Twist The expression of TGF-β1 was correlated with those of E-cadherin,N-cadherin and Twist.Conclusions:The reduced expression of E-cadherin,abnormal expression of N-cadherin,transformation form E-cadherin to N-cadherin and the increased expression of TGF-β1 and Twist play an important role in the occurrence and development of prostate cancer.

Influence of ginsenoside Rg1, a panaxatriol saponin from Panax notoginseng, on renal fibrosis in rats with unilateral ureteral obstruction

Total saponins of Panax notoginseng （PNS） have been shown to ameliorate renal interstitial fibrosis. Ginsenoside Rg 1, a panaxatriol saponin, is one of the major active molecules from PNS. The present study was undertaken to investigate the effect of ginsenoside Rgl on renal fibrosis in rats with unilateral ureteral obstruction （UUO）. The rats were randomly divided into 3 groups： sham-operation （n=15）, UUO （n=15） and UUO with ginsenoside Rgl treatment （n=15, 50 mg per kg body weight, intraperitoneally （i.p.） injected）. The rats were sacrificed on Days 7 and 14 after the surgery. Histological examination demonstrated that ginsenoside Rgl significantly inhibited interstitial fibrosis including tubular injury as well as collagen deposition, u-smooth muscle actin （α-SMA） and E-cadherin are two markers of tubular epithelial-myofibroblast transition （TEMT）. Interestingly, ginsenoside Rgl notably decreased α-SMA expression and simultaneously enhanced E-cadherin expression. The messenger RNA （mRNA） of transforming growth factor-β1 （TGF-β1）, a key mediator to regulate TEMT, in the obstructed kidney increased dramatically, but was found to decrease significantly after administration of ginsenoside Rg 1. Further study showed that ginsenoside Rgl considerably decreased the levels of both active TGF-β1 and phosphorylated Smad2 （pSmad2）. Moreover, ginsenoside Rgl substantially suppressed the expression of thrombospondin-1 （TSP-1）, a cytokine which can promote the transcription of TGF-β1 mRNA and the activation of latent TGF-β1. These results suggest that ginsenoside Rgl inhibits renal interstitial fibrosis in rats with UUO. The mechanism might be partly related to the blocking of TEMT via suppressing the expression of TSP-1.