Impairment of Assembly of the Vimentin Intermediate Filaments Leads to Suppression of Formation and Maturation of Focal Contacts and Alteration of the Type of Cellular Protrusions.

Cell migration is largely determined by the type of protrusions formed by the cell. Mesenchymal migration is accomplished by formation of lamellipodia and/or filopodia, while amoeboid migration is based on bleb formation. Changing of migrational conditions can lead to alteration in the character of cell movement. For example, inhibition of the Arp2/3-dependent actin polymerization by the CK-666 inhibitor leads to transition from mesenchymal to amoeboid motility mode. Ability of the cells to switch from one type of motility to another is called migratory plasticity. Cellular mechanisms regulating migratory plasticity are poorly understood. One of the factors determining the possibility of migratory plasticity may be the presence and/or organization of vimentin intermediate filaments (VIFs). To investigate whether organization of the VIF network affects the ability of fibroblasts to form membrane blebs, we used rat embryo fibroblasts REF52 with normal VIF organization, fibroblasts with vimentin knockout (REF-/-), and fibroblasts with mutation inhibiting assembly of the full-length VIFs (REF117). Blebs formation was induced by treatment of cells with CK-666. Vimentin knockout did not lead to statistically significant increase in the number of cells with blebs. The fibroblasts with short fragments of vimentin demonstrate the significant increase in number of cells forming blebs both spontaneously and in the presence of CK-666. Disruption of the VIF organization did not lead to the significant changes in the microtubules network or the level of myosin light chain phosphorylation, but caused significant reduction in the focal contact system. The most pronounced and statistically significant decrease in both size and number of focal adhesions were observed in the REF117 cells. We believe that regulation of the membrane blebbing by VIFs is mediated by their effect on the focal adhesion system. Analysis of migration of fibroblasts with different organization of VIFs in a three-dimensional collagen gel showed that organization of VIFs determines the type of cell protrusions, which, in turn, determines the character of cell movement. A novel role of VIFs as a regulator of membrane blebbing, essential for manifestation of the migratory plasticity, is shown.

[Different calcium ion concentrations affect epithelial mesenchymal transformation of human peritoneal mesothelial cells via endoplasmic reticulum stress].

OBJECTIVE: To study the effects of different calcium ion concentrations on epithelial mesenchymal transformation (EMT) of human peritoneal mesothelial cell (HPMC) via endoplasmic reticulum stress (ERS). METHODS: HPMC cell line HMrSV5 was cultured in vitro and treated in groups. The cells in the control group, high calcium group 1, and high calcium group 2 were treated with medium containing calcium ion concentrations of 1.25, 1.75, and 2.25 mmol/L, respectively. The solvent control group was treated with medium containing 1.25 mmol/L physiological calcium ion concentration and 0.1% dimethyl sulfoxide (DMSO), the high calcium+solvent group was treated with medium containing 2.25 mmol/L calcium ion concentration and 0.1% DMSO, the high calcium+4-phenylbutyric acid (4-PBA) group was treated with medium containing 2.25 mmol/L calcium ion concentration and 1 mmol/L ERS inhibitor 4-PBA, and each group was treated for 48 hours. Morphological changes of cells in each group were observed under light microscope. The expressions of epithelial cell phenotype marker zonula occluden-1 (ZO-1) and mesenchymal cell phenotype marker α-smooth muscle actin (α-SMA) in the cells were observed by immunofluorescence staining. The expressions of EMT marker genes E-cadherin, ZO-1, α-SMA and Vimentin were detected by fluorescence quantitative polymerase chain reaction (PCR). The expressions of ERS marker proteins phosphorylated protein kinase R-like endoplasmic reticulum kinase (p-PERK), phosphorylated eukaryotic initiation factor 2α (p-eIF2α), transcription activating factor 4 (ATF4) and C/EBP homologous protein (CHOP) were detected by Western blotting. RESULTS: Compared with the control group, the morphology of HMrSV5 cells became slender and fibrotic, the fluorescence intensity of ZO-1 increased, and the fluorescence intensity of α-SMA decreased in high calcium 1 and high calcium 2 groups, indicating that the cells transformed from epithelial cells to mesenchyme cells. The mRNA expressions of E-cadherin and ZO-1 were significantly decreased, while the mRNA expressions of α-SMA and Vimentin and the protein expressions of p-PERK, p-eIF2α, ATF4 and CHOP were significantly increased, moreover, the expressions of the above marker genes or proteins in the high calcium 2 group was more obvious than those in the high calcium 1 group [E-cadherin mRNA (2-ΔΔCt): 0.53±0.05 vs. 0.75±0.09, ZO-1 mRNA (2-ΔΔCt): 0.42±0.06 vs. 0.69±0.06, α-SMA mRNA (2-ΔΔCt): 1.81±0.16 vs. 1.32±0.14, Vimentin mRNA (2-ΔΔCt): 2.05±0.22 vs. 1.48±0.16, p-PERK protein (p-PERK/ß-actin): 0.81±0.09 vs. 0.59±0.06, p-eIF2α protein (p-eIF2α/ß-actin): 0.87±0.10 vs. 0.50±0.06, ATF4 protein (ATF4/ß-actin): 0.93±0.10 vs. 0.72±0.06, CHOP protein (CHOP/ß-actin): 0.79±0.09 vs. 0.46±0.04, all P < 0.05]. Compared with the solvent control group, the morphological changes of cells, the expressions of EMT marker genes and ERS marker proteins after high calcium ion concentration of 2.25 mmol/L were consistent with those in the high calcium 2 group than control group. Compared with the high calcium+solvent group, the cell morphology recovered the characteristics of polygonal and pebble-like epithelial cells in the high calcium+4-PBA group, the fluorescence intensity of ZO-1 increased, the fluorescence intensity of α-SMA decreased, and the mRNA expressions of E-cadherin and ZO-1 in the cells were significantly increased [E-cadherin mRNA (2-ΔΔCt): 0.86±0.09 vs. 0.57±0.04, ZO-1 mRNA (2-ΔΔCt): 0.81±0.06 vs. 0.48±0.05, both P < 0.05], the mRNA expressions of α-SMA and Vimentin and the protein expressions of p-PERK, p-eIF2α, ATF4 and CHOP were significantly decreased [α-SMA mRNA (2-ΔΔCt): 1.21±0.13 vs. 1.77±0.15, Vimentin mRNA (2-ΔΔCt): 1.30±0.14 vs. 1.94±0.20, p-PERK protein (p-PERK/ß-actin): 0.38±0.04 vs. 0.92±0.11, p-eIF2α protein (p-eIF2α/ß-actin): 0.34±0.05 vs. 1.05±0.13, ATF4 protein (ATF4/ß-actin): 0.57±0.06 vs. 0.97±0.11, CHOP protein (CHOP/ß-actin): 0.51±0.04 vs. 0.90±0.12, all P < 0.05]. CONCLUSIONS: High calcium ion concentrations of 1.75 mmol/L and 2.25 mmol/L promote EMT of HPMC via activating ERS.

Molecular mechanism of triptolide in myocardial fibrosis through the Wnt/ß-catenin signaling pathway.

Objective. Myocardial fibrosis (MF) is a common manifestation of end-stage cardiovascular diseases. Triptolide (TP) provides protection against cardiovascular diseases. This study was to explore the functional mechanism of TP in MF rats via the Wnt/ß-catenin pathway. Methods. The MF rat model was established via subcutaneous injection of isoproterenol (ISO) and treated with low/medium/high doses of TP (L-TP/M-TP/H-TP) or Wnt agonist BML-284. Cardiac function was examined by echocardiography. Pathological changes of myocardial tissues were observed by HE and Masson staining. Col-I/Col-III/Vimentin/α-SMA levels were detected by immunohistochemistry, RT-qPCR, and Western blot. Collagen volume fraction content was measured. Expression levels of the Wnt/ß-catenin pathway-related proteins (ß-catenin/c-myc/Cyclin D1) were detected by Western blot. Rat cardiac fibroblasts were utilized for in vitro validation experiments. Results. MF rats had enlarged left ventricle, decreased systolic and diastolic function and cardiac dysfunction, elevated collagen fiber distribution, collagen volume fraction and hydroxyproline content. Levels of Col-I/Col-III/Vimentin/α-SMA, and protein levels of ß-catenin/c-myc/Cyclin D1 were increased in MF rats. The Wnt/ß-catenin pathway was activated in the myocardial tissues of MF rats. TP treatment alleviated impairments of cardiac function and myocardial tissuepathological injury, decreased collagen fibers, collagen volume fraction, Col-I, Col-III, α-SMA and Vimentin levels, HYP content, inhibited Wnt/ß-catenin pathway, with H-TP showing the most significant effects. Wnt agonist BML-284 antagonized the inhibitive effect of TP on MF. TP inhibited the Wnt/ß-catenin pathway to repress the proliferation and differentiation of mouse cardiac fibroblasts in vitro. Conclusions. TP was found to ameliorate ISO-induced MF in rats by inhibiting the Wnt/ß-catenin pathway.

Carbonate apatite increases gene expression of osterix and bone morphogenetic protein 2 in the alveolar ridge after socket grafting.

PURPOSE: After tooth extraction, preservation of the alveolar ridge by socket grafting attenuates bone resorption. Runt-related transcription factor 2 (RUNX2) and SP7/Osterix (OSX) are transcription factors playing an important role in osteoblast differentiation. The purpose of this study was to evaluate the effects of carbonate apatite (CO3Ap) on osteoblast-related gene and protein expression after socket grafting. METHODS: Alveolar bone and new bone after CO3Ap grafting were collected at the time of implant placement. Levels of mRNA for RUNX2, SP7/OSX, bone morphogenetic protein 2 (BMP2), BMP7 and platelet derived growth factor B were determined by real-time PCR. Immunostaining was performed using antibodies against RUNX2, SP7/OSX, vimentin and cytokeratin. To evaluate bone resorption rates, cone-beam CT (CBCT) imaging was performed after socket grafting and before implant placement. RESULTS: CBCT imaging showed that the average degree of bone resorption at the CO3Ap graft site was 7.15 ± 3.79%. At the graft sites, levels of SP7/OSX and BMP2 mRNA were significantly increased. Replacement of CO3Ap with osteoid was evident histologically, and in the osteoid osteoblast-like cells were stained for SP7/OSX and vimentin. CONCLUSION: These results show that gene expression of both SP7/OSX and BMP2 can be induced by CO3Ap, suggesting that increased expression of SP7/OSX and vimentin may be involved in the BMP pathway.

HBx Modulates Drug Resistance of Sorafenib-Resistant Hepatocellular Carcinoma Cells.

BACKGROUND: Approximately 50% of hepatocellular carcinoma (HCC) arises due to the infection by hepatitis B virus X protein (HBx). Sorafenib, a unique targeted oral kinase inhibitor, is the therapeutic agent of choice for advanced HCC. The mechanism of HBx in drug resistance of sorafenib-resistant HCC cells was evaluated in this study. METHODS: Employing a stepwise increase of the sorafenib content, Hep3B and HepG2 cells were iteratively induced to establish drug-resistant cell lines (Hep3B/R and HepG2/R). The survival rate of Hep3B, Hep3B/R, HepG2, and HepG2/R cells was estimated using the cell counting kit-8 (CCK-8) assay. The IC50 values of sorafenib were calculated, exploring its effects under varying concentrations. The HBx content was quantified via quantitative reverse transcription PCR (RT-qPCR) and Western Blot. HBx overexpression and interfering virus vectors were constructed and transfected into Hep3B/R and HepG2/R cells. Cell viability and metastasis were assessed by colony formation, wound healing, and transwell assays. E-cadherin, N-cadherin, Vimentin, Slug, and Snail content was evaluated via Western Blot. RESULTS: HBx content was significantly elevated in Hep3B/R and HepG2/R subgroups compared to Hep3B and HepG2 subgroups. The proliferation, clonogenicity, invasiveness, and migratory abilities of Hep3B/R and HepG2/R cells in the HBx subgroup were markedly enhanced; E-cadherin content was significantly reduced, whereas the content of N-cadherin, Vimentin, Slug, and Snail was significantly elevated in the HBx subgroup. Conversely, in the sh-HBx subgroup, the proliferation, clonogenicity, invasion, and migration of Hep3B/R and HepG2/R cells were significantly reduced, E-cadherin content was markedly increased, and N-cadherin, Vimentin, Slug, and Snail content was significantly reduced, compared to the sh-negative control (NC) subgroup. CONCLUSIONS: HBx knockout may affect the development of HCC by reducing the proliferation, invasion, and migration of Hep3B/R and HepG2/R cells through the inhibition of Epithelial-Mesenchymal Transition (EMT).

[Aumolertinib inhibits proliferation, invasion and migration and promotes apoptosis of neuroblastoma cells by downregulating MMP2 and MMP9 expression].

OBJECTIVE: To investigate the effects of aumolertinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), on biological behaviors of neuroblastoma SH-SY5Y cells. METHODS: CCK-8 assay, colony-forming assay, Transwell assay and flow cytometry were used to assess the effects of 2, 4 and 8 µmol/L aumolertinib on proliferation, survival, migration, invasion and apoptosis of SH-SY5Y cells, and the changes in ultrastructure of the cells were observed using transmission electron microscopy. The protein expressions of Bax, Bcl-2, E-cadherin, vimentin, MMP2, and MMP9 in the treated cells were detected using Western blotting. A nude mouse model bearing subcutaneous SH-SY5Y cell xenograft were treated with aumolertinib (15 mg/kg) or cyclophosphamide (20 mg/kg), and the tumor volume and body mass changes was measured. HE staining was used to observe adverse effects of the treatment on the heart, liver, spleen, lungs and kidneys. RESULTS: Aumolertinib significantly inhibited the proliferation and viability of SH-SY5Y cells (P<0.05) with IC50 of 5.004, 3.728 and 3.228 µmol/L at 24, 48 and 72 h, respectively. Aumolertinib treatment induced obvious apoptosis of the cells, which showed characteristic morphological changes of apoptosis under transmission electron microscope. The treatment also inhibited the invasion and migration abilities of SH-SY5Y cells (P<0.01), up-regulated the expression levels of E-cadherin and Bax and lowered the expression levels of Bcl-2, vimentin, MMP2 and MMP9 (P<0.05). In the nude mouse models, treatment with aumolertinib effectively inhibited the growth of neuroblastoma without causing significant toxicity to the vital organs. CONCLUSION: Aumolertinib inhibits proliferation, survival, invasion and migration and induces apoptosis in SH-SY5Y cells by downregulating MMP2 and MMP9 expression.

Ephedrine alleviates bleomycin-induced pulmonary fibrosis by inhibiting epithelial-mesenchymal transition and restraining NF-κB signaling.

Pulmonary fibrosis is a lethal and progressive pulmonary disorder in human beings. Ephedrine is a compound isolated from Ephedra and plays a regulatory role in inflammatory response. This study focused on the anti-pulmonary fibrosis effect of ephedrine and its potential molecular mechanism. After a mouse model of pulmonary fibrosis was established through bleomycin (BLM) induction, the survival percentage, body weight, and pulmonary index were measured. Hematoxylin-eosin staining and Masson's trichrome staining for lung tissues were performed to observe the pathological alterations. The viability of lung epithelial BEAS-2B cells, intracellular production of reactive oxygen species, and the levels of pro-inflammatory cytokines were examined by cell counting kit-8 assays, 2',7'-dichlorofluorescein diacetate (DCF-DA) staining, and enzyme-linked immunosorbent assay, respectively. Immunofluorescence staining was performed to determine E-cadherin and vimentin expression after BLM or ephedrine treatment. The mRNA and protein levels of cytokeratin-8, E-cadherin, α-SMA, and vimentin were subjected to quantitative polymerase chain reaction and immunoblotting. Experimental results revealed that ephedrine treatment rescued the repressive impact of BLM on BEAS-2B cell viability, and ephedrine inhibited BLM-induced overproduction of reactive oxygen species and inflammatory response in BEAS-2B cells. Additionally, ephedrine suppressed epithelial-mesenchymal transition (EMT) process stimulated by BLM treatment, as demonstrated by the reduced α-SMA and vimentin levels together with the increased cytokeratin-8 and E-cadherin levels in BLM + Ephedrine group. In addition, ephedrine inhibited NF-κB and activated Nrf-2 signaling in BLM-treated BEAS-2B cells. Moreover, ephedrine ameliorated pulmonary fibrosis in BLM-induced mice and improved the survival of model mice. In conclusion, ephedrine attenuates BLM-evoked pulmonary fibrosis by repressing EMT process via blocking NF-κB signaling and activating Nrf-2 signaling, suggesting that ephedrine might become a potential anti-pulmonary fibrosis agent in the future.

Effect of emodin combined with cisplatin on the invasion and migration of HepG2 hepatoma cells.

Cisplatin is the leading chemotherapy agent for advanced liver cancer. However, the resistance to cisplatin in liver cancer reduces its efficacy. A potential strategy to increase its effectiveness and reduce toxicity is to combine cisplatin with 1,3,8-trihydroxy-6-methylanthraquinone (emodin). In this study, we examined the effects of emodin combined with cisplatin on the invasion and migration of HepG2 cells and analyzed the role of emodin. The effects of cisplatin, emodin and their combination were assessed in HepG2 cells. Proliferation, invasion and migration of HepG2 cells were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), scar and Transwell assays. The gelatinase spectrum and an ELISA detected the expression of matrix metallopeptidase 2 (MMP-2) and matrix metallopeptidase 9 (MMP-9). The expression of E-cadherin and vimentin was detected by immunofluorescence and Western blots. Emodin inhibited cell invasion and migration in HepG2 hepatoma cells, increased E-cadherin expression, decreased vimentin, MMP-2, and MMP-9 expression. The combination of emodin and cisplatin-induced a more significant effect in a dose-dependent manner. In this study, we found that emodin inhibited hepatocellular carcinoma (HCC) metastasis. Compared with either cisplatin or emodin alone, the combination of both showed a more significant synergistic effect. Emodin can enhance the sensitivity of HepG2 HCC cells to cisplatin by inhibiting epithelial-mesenchymal transition, and thus, play a role in preventing recurrence and metastasis in HCC.

Circular RNA circARPC1B functions as a stabilisation enhancer of Vimentin to prevent high cholesterol-induced articular cartilage degeneration.

BACKGROUND: Osteoarthritis (OA) is a prevalent and debilitating condition, that is, directly associated with cholesterol metabolism. Nevertheless, the molecular mechanisms of OA remain largely unknown, and the role of cholesterol in this process has not been thoroughly investigated. This study aimed to investigate the role of a novel circular RNA, circARPC1B in the relationship between cholesterol and OA progression. METHODS: We measured total cholesterol (TC) levels in the synovial fluid of patients with or without OA to determine the diagnostic role of cholesterol in OA. The effects of cholesterol were explored in human and mouse chondrocytes in vitro. An in vivo OA model was also established in mice fed a high-cholesterol diet (HCD) to explore the role of cholesterol in OA. RNAseq analysis was used to study the influence of cholesterol on circRNAs in chondrocytes. The role of circARPC1B in the OA development was verified through circARPC1B overexpression and knockdown. Additionally, RNA pulldown assays and RNA binding protein immunoprecipitation were used to determine the interaction between circARPC1B and Vimentin. CircARPC1B adeno-associated virus (AAV) was used to determine the role of circARPC1B in cholesterol-induced OA. RESULTS: TC levels in synovial fluid of OA patients were found to be elevated and exhibited high sensitivity and specificity as predictors of OA diagnosis. Moreover, elevated cholesterol accelerated OA progression. CircARPC1B was downregulated in chondrocytes treated with cholesterol and played a crucial role in preserving the extracellular matrix (ECM). Mechanistically, circARPC1B is competitively bound to the E3 ligase synoviolin 1 (SYVN1) binding site on Vimentin, inhibiting the proteasomal degradation of Vimentin. Furthermore, circARPC1B AAV infection alleviates Vimentin degradation and OA progression caused by high cholesterol. CONCLUSIONS: These findings indicate that the cholesterol-circARPC1B-Vimentin axis plays a crucial role in OA progression, and circARPC1B gene therapy has the opportunity to provide a potential therapeutic approach for OA.

Kinesin family member 23 knockdown inhibits cell proliferation and epithelial-mesenchymal transition in esophageal carcinoma by inactivating the Wnt/ß-catenin pathway.

Kinesin family member 23 (KIF23) serves as a tumor-promoting gene with prognostic values in various tumors. However, the role of KIF23 in esophageal carcinoma (ESCA) progression is largely unknown. The overlapping differentially expressed genes (DEGs) in GSE12452, GSE17351, and GSE20347 datasets were identified via GEO2R tool and Venn diagram software. KIF23 expression was analyzed using GSE12452, GSE17351, and GSE20347 datasets, GEPIA database, and qRT-PCR. Cell proliferation was assessed by CCK-8 and EdU incorporation assays. Gene set enrichment analysis (GSEA) analysis was performed to investigate the pathways associated with the regulatory mechanisms of KIF23 in ESCA. The expression of E-cadherin, vimentin, N-cadherin, and matrix metalloproteinase-9 (MMP-9) and alternation of Wnt/ß-catenin pathway were detected by western blot analysis. We identified two overlapping upregulated DEGs, among which KIF23 was selected for subsequent experiments. KIF23 was overexpressed in ESCA samples and cells, and knockdown of KIF23 retarded cell proliferation in ESCA cells. Besides, KIF23 knockdown suppressed epithelial-mesenchymal transition (EMT) process in ESCA cells, as evidenced by the increase of E-cadherin expression and the reduction of vimentin, N-cadherin, and MMP-9 expression. GSEA analysis suggested that Wnt signaling pathway was the significant pathway related to KIF23. Moreover, we demonstrated that KIF23 silencing inhibited the Wnt/ß-catenin pathway in ESCA cells. Activation of Wnt/ß-catenin pathway by SKL2001 reversed the effects of KIF23 silencing on cell proliferation and EMT in ESCA cells. In conclusion, KIF23 knockdown inhibited the proliferation and EMT in ESCA cells through blockage of Wnt/ß-catenin pathway.

Efficacy of Danggui Buxue decoction on diabetic nephropathy-induced renal fibrosis in rats and possible mechanism.

OBJECTIVE: To observe the efficacy of Danggui Buxue decoction (, DBD) on diabetic nephropathy-induced renal fibrosis in rats, and to study the possible mechanism. METHODS: Sixty male Goto Kakizaki (GK) rats were randomly assigned to the model group, gliquidone group, astragaloside IV group, and high-, medium- and low-doses DBD groups. After 8 weeks, changes in body weight, blood glucose, serum creatinine, serum urea nitrogen, and total cholesterol were observed. Changes in transforming growth factor-ß1 (TGF-ß1), Smad3, and Smad5 pathways and the expression of the fibrosis-related proteins collagen IV (col IV), α-smooth muscle actin (α-SMA), and vimentin were assessed. The degree of renal fibrosis was observed by immunohistochemistry and Mason staining. The expression of interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor (TNF-α), and C-reactive protein (CRP) in the kidneys was assessed using enzyme linked immunosorbent assay. RESULTS: Our experiments showed that DBD effectively reduced blood glucose, blood urea nitrogen, and creatinine levels after 8 weeks of administration, improved renal function in diabetic rats, alleviated renal fibrosis, and reduced the renal tissue levels of IL-6, IL-10, TNF-α, and CRP. Furthermore, DBD decreased the expression of TGF-ß1, Smad3, col IV, α-SMA, and vimentin in renal tissues and increased the expression of Smad5. CONCLUSIONS: DBD ameliorates diabetic renal interstitial fibrosis by modulating the TGF-ß1/Smads pathway.

CircRNA7632 down-regulation alleviates endothelial cell dysfunction in Kawasaki disease via regulating IL-33 expression.

Kawasaki disease (KD) is a form of idiopathic vasculitis frequently accompanied by coronary artery lesions, which involves endothelial dysfunction. Recent studies have demonstrated that circular RNAs (circRNAs) are implicated in many cardiovascular diseases. However, few studies have examined the role of circRNAs on endothelial dysfunction in KD. In this study, we investigated the role of circ7632 on endothelial-mesenchymal transition (EndoMT) in KD and then explored the underlying mechanism. Children diagnosed with KD and age-matched healthy controls (HC) were included. Sera samples were collected. Primary human umbilical vein endothelial cells (HUVECs) were obtained and incubated with 15% HC and KD serum for 48 h. The mRNA and protein expression of mesenchymal markers vimentin and α-smooth muscle actin (α-SMA) and endothelial marker zonula occludens-1 (ZO-1) in HUVECs transfected with plasmid-circ7632 and si-circ7632 were detected by RT-qPCR and Western blot analysis. CCK8, scratch test, and migration test were performed to examine the effect of circ7632 on the cell proliferation and migration. The circ7632 level was higher in HUVECs treated by KD serum than in HUVECs treated with HC serum. Overexpression of circ7632 significantly increased vimentin and α-SMA expression, decreased ZO-1 expression, and also decreased cell proliferation. Down-regulation of circ7632 expression got the opposite results. RNA-seq analysis, and confirmatory experiment displayed that down-regulation of circ7632 decreased IL-33 expression, and IL-33 silencing mitigated KD serum-mediated EndoMT. Our study revealed that circ7632 level was elevated in KD serum-treated HUVECs. Circ7632 down-regulation could alleviate EndoMT likely through decreasing IL-33 expression. The circ7632 may become a potential therapeutic target for KD.

ß-Elemene regulates epithelial-mesenchymal transformation and inhibits invasion and metastasis of colorectal cancer cells.

OBJECTIVES: To study the inhibitory effect of ß-elemene on invasion and metastasis of colorectal cancer cells and its possible mechanism. METHODS: Human colon cancer HCT116 cells were treated with different concentrations of ß-elemene. The proliferation inhibition rate of the cells was detected by MTT assay, cell migration rate was detected by scratched assay, and cell invasion rate was evaluated by Transwell cell invasion assay. The expressions of Vimentin, E-cadherin, N-cadherin, and ß-catenin were detected by Western blotting. The mRNA expressions of Vimentin, E-cadherin, N-cadherin, and ß-catenin were detected by real-time PCR. RESULTS: Compared with the control group, the expressions of migration rate, invasion rate, scratch healing rate, N-cadherin, and Vimentin protein of HCT116 cells were decreased after ß-elemene treatment, while the expression of E-cadherin protein was increased, and the inhibition rate of cell proliferation was increased (p<0.05). CONCLUSIONS: ß-Elemene may inhibit cell proliferation and invasion and metastasis by inhibiting EMT signaling pathway in human colon cancer cell line HCT116.

Chlorogenic Acid Inhibits Epithelial-Mesenchymal Transition and Invasion of Breast Cancer by Down-Regulating LRP6.

Epithelial-mesenchymal transition (EMT) is a crucial biologic process for breast cancer metastasis, and inhibition of EMT could be an effective approach to suppress metastatic potential of mammary cancer. High expression of low-density lipoprotein receptor-related protein 6 (LRP6) is usually observed in breast carcinoma and predicts poor prognosis. In the present study, we investigated whether chlorogenic acid (CA) can inhibit the EMT of breast cancer cells and underlying molecular mechanism. We found that CA treatment transformed MCF-7 cell morphology from spindle shape (mesenchymal phenotype) to spherical shape (epithelial phenotype). CA clearly increased epithelial biomarkers' expression (E-cadherin and ZO-1) but decreased mesenchymal proteins' expression (ZEB1, N-cadherin, vimentin, snail, and slug). In addition, CA attenuated MMP-2 and MMP-9 activities and inhibited cell migration and invasion. CA downregulated the expression of LRP6 in MCF-7 cells. Knockdown LRP6 with siRNA repressed cell mobility and invasion, wheras overexpression of LRP6 promoted EMT and antagonized the EMT inhibitory effect of CA on MCF-7 cells. Furthermore, CA directly interacted with Wnt/ß-catenin signaling coreceptor LRP6 and reduced LRP6, p-LRP6, and ß-catenin expression levels in MCF-7 cells. In vivo study revealed that CA notably reduced tumor volume and tumor weight. CA decreased the expression of LRP6, N-cadherin, ZEB1, vimentin, MMP2, MMP9, and increased the expression of E-cadherin and ZO-1. In conclusion, CA inhibited EMT and invasion of breast cancer by targeting LRP6. SIGNIFICANCE STATEMENT: CA, the familiar polyphenol compound in traditional Chinese medicine, repressed EMT and weakened cellular mobility and invasion in MCF-7 cells. The mechanism studies demonstrated that CA could inhibit EMT and invasion of MCF-7 cells via targeting LRP6. Additionally, CA restrained tumor growth and xenograft tumor EMT in vivo. The EMT inhibitory property of CA warrants further studies of CA as a drug candidate for the therapy of metastatic breast carcinoma.

The role of PI3K/AKT-related proteins in di(2-ethyl)hexylphthalate-induced BG-1 and MCF-7 cell proliferation, and inhibition by metformin.

OBJECTIVE: To investigate the molecular mechanism of the proliferation and migration of BG-1 and MCF-7cells induced by DEHP, and the antagonistic effect of metformin. METHODS: The proliferation, cell cycle progression, migration, and invasion abilities of BG-1 and MCF-7 cancer cells were examined via Cell Counting Kit-8, flow cytometry, Transwell, and scratch assays. E2F1, SKP2, cyclin D1, vimentin, E-cadherin, and GSK-3ß, all of which play key roles in cancer development via the PI3K/AKT signaling pathway, were examined by immunofluorescence and immunocytochemistry. RESULTS: Cell proliferation was significantly increased, and the wound closure and number of trans-membrane migrating cells were significantly increased, by DHEP treatment. The numbers of BG-1 and MCF-7 cells in the G0/G1 phase were significantly decreased, while those in the S phase were significantly increased. Increased E2F1, SKP2, cyclin D1, and vimentin levels and decreased E-cadherin and GSK-3ß levels were detected in BG-1 and MCF-7 cells treated with DEHP compared to that in control cells. Furthermore, DEHP-induced effects were markedly inhibited by LY294002 (a PI3K/AKT inhibitor) or metformin. CONCLUSION: We demonstrated that DEHP-induced cell proliferation and migration involves the PI3K/AKT signaling pathway and that metformin can be used to inhibit this proliferation and migration.

GPR55 activation prevents amphetamine-induced conditioned place preference and decrease the amphetamine-stimulated inflammatory response in the ventral hippocampus in male rats.

Inflammatory response in the Central Nervous System (CNS) induced by psychostimulants seems to be a crucial factor in the development and maintenance of drug addiction. The ventral hippocampus (vHp) is part of the reward system involved in substance addiction and expresses abundant G protein-coupled receptor 55 (GPR55). This receptor modulates the inflammatory response in vitro and in vivo, but there is no information regarding its anti-inflammatory effects and its impact on psychostimulant consumption. The aim of the present study was to investigate whether vHp GPR55 activation prevents both the inflammatory response induced by amphetamine (AMPH) in the vHp and the AMPH-induced conditioned place preference (A-CPP). Wistar adult male rats with a bilateral cannula into the vHp or intact males were subjected to A-CPP (5 mg/kg). Upon the completion of A-CPP, the vHp was dissected to evaluate IL-1ß and IL-6 expression through RT-PCR, Western blot and immunofluorescence. Our results reveal that AMPH induces both A-CPP and an increase of IL-1ß and IL-6 in the vHp. The GPR55 agonist lysophosphatidylinositol (LPI, 10 µM) infused into the vHp prevented A-CPP and the AMPH-induced IL-1ß increase. CID 16020046 (CID, 10 µM), a selective GPR55 antagonist, abolished LPI effects. To evaluate the effect of the inflammatory response, lipopolysaccharide (LPS, 5 µg/µl) was infused bilaterally into the vHp during A-CPP acquisition. LPS strengthened A-CPP and increased IL-1ß/IL-6 mRNA and protein levels in the vHp. LPS also increased CD68, Iba1, GFAP and vimentin expression. All LPS-induced effects were blocked by LPI. Our results suggest that GPR55 activation in the vHp prevents A-CPP while decreasing the local neuro-inflammatory response. These findings indicate that vHp GPR55 is a crucial factor in preventing the rewarding effects of AMPH due to its capacity to interfere with proinflammatory responses in the vHp.

[Protective effect of active vitamin D on liver fibrosis induced by sodium arsenite in SD rats].

OBJECTIVE: To explore the protective effect of active vitamin D(VD) on liver fibrosis injury induced by sodium arsenite(NaAsO_2) in SD rats. METHODS: Eighteen healthy newly weaned SD rats, half male and half female, were randomly divided into Control group(gavaged with 10 mL/kg normal saline), NaAsO_2-treated group(gavaged with 10 mg/kg NaAsO_2), Active VD(calcitriol) intervention group(gavaged with 10 mg/kg NaAsO_2 and 1.0 µg/kg calcitriol was given by gavage along with NaAsO_2 administration after 12 weeks), all rats were administered 6 days a week for 36 weeks and weighed every week. Enzyme-linked immunosorbent(ELISA) was used to detect the secretion levels of 25(OH)D_3 and hyaluronic acid(HA), laminin(LN), type Ⅲ pre-collagen amino-terminal peptide(PⅢNP), type Ⅳ collagen(COL-Ⅳ) in the serum of rats in each group; HE staining was used to observe the basic pathological changes of liver tissues in each group, Masson and Sirius Red staining were used to observe the fibrosis and collagen deposition of liver tissues in each group; Western Blot was used to detected the protein levels of fibrosis-related markers α-smooth actin(α-SMA), transforming growth factor-ß1(TGF-ß1) and Vimentin in each group. RESULTS: After 36 weeks of NaAsO_2 exposure, the weight of rats was significantly decreased compared with the control group, and the weight of female rats after calcitriol intervention was significantly increased compared with NaAsO_2-treated group(P<0.05). The result of liver coefficient showed increasing in NaAsO_2-treated group compared with the control group, while decreasing in calcitriol intervention group compared with NaAsO_2-treated group, and the difference was statistically significant in female rats. ELISA assay showed that compared with the control group((550.21±29.16) ng/L), the serum level of 25(OH)D_3 in NaAsO_2-treated group((436.82±74.37) ng/L) was significantly decreased(P<0.05), while the serum level of 25(OH)D_3 was significantly higher in calcitriol intervention group than that of NaAsO_2-treated group(P<0.05). HE staining found that, compared with the control group, the liver tissue of rats in NaAsO_2-treated group showed abnormal morphology, the liver tissue was structurally disordered, false lobules and fat vacuoles were also increased. Masson and Sirius Red staining also revealed abnormal hepatic lobule structure, enlarged and deformed portal area and abundant collagen fiber deposition in NaAsO_2-treated group. Further analysis showed that the positive staining area of collagen deposition in liver tissue of rats exposed to NaAsO_2 increased significantly compared with the control group(P<0.05). Those above changes in calcitriol intervention group were significantly alleviated compared with NaAsO_2-treated group(P<0.05). Western Blot analysis showed that the protein levels of α-SMA, TGF-ß1 and Vimentin were obviously higher in NaAsO_2-treated group(1.12±0.21, 1.12±0.26, 1.31±0.15) than that in the control group(0.57±0.10, 0.64±0.13, 0.72±0.16)(P<0.05). In addition, the serum levels of HA, LN, PⅢNP and COL-Ⅳ in rats exposed to NaAsO_(2 )((87.92±9.67), (89.04±11.91), (12.09±2.97) and(19.86±3.40)ng/mL) were also higher than those in control group. After calcitriol intervention, the protein levels of α-SMA, TGF-ß1 and Vimentin(0.68±0.16, 0.85±0.21, 0.84±0.09) in liver tissue and the serum levels of HA, LN, PⅢNP and COL-Ⅳ((54.29±7.23), (55.56±9.43), (6.49±1.08), (10.15±1.99) ng/mL) were significantly lower than those of NaAsO_2-treated group(P<0.05). CONCLUSION: Calcitriol can effectively alleviate liver fibrosis injury caused by long-term NaAsO_2 exposure in SD rats.

Nickel nanoparticles induce epithelial-mesenchymal transition in human bronchial epithelial cells via the HIF-1α/HDAC3 pathway.

We and others have previously demonstrated that exposure to nickel nanoparticles (Nano-Ni) caused fibrogenic and carcinogenic effects; however, the underlying mechanisms are still not fully understood. This study aimed to investigate the effects of Nano-Ni on epithelial-mesenchymal transition (EMT) in human bronchial epithelial cells (BEAS-2B) and its underlying mechanisms since EMT is involved in both cancer pathogenesis and tissue fibrosis. Our results showed that exposure to Nano-Ni, compared to the control Nano-TiO2, caused a remarkable decrease in the expression of E-cadherin and an increase in the expression of vimentin and α-SMA, indicating an inducible role of Nano-Ni in EMT development in human bronchial epithelial cells. HIF-1α nuclear accumulation, HDAC3 upregulation, and decreased histone acetylation were also observed in the cells exposed to Nano-Ni, but not in those exposed to Nano-TiO2. Pretreatment of the cells with a specific HIF-1α inhibitor, CAY10585, or HIF-1α-specific siRNA transfection prior to Nano-Ni exposure resulted in the restoration of E-cadherin and abolished Nano-Ni-induced upregulation of vimentin and α-SMA, suggesting a crucial role of HIF-1α in Nano-Ni-induced EMT development. CAY10585 pretreatment also attenuated the HDAC3 upregulation and increased histone acetylation. Inhibition of HDAC3 with specific siRNA significantly restrained Nano-Ni-induced reduction in histone acetylation and restored EMT-related protein expression to near control levels. In summary, our findings suggest that exposure to Nano-Ni promotes the development of EMT in human bronchial epithelial cells by decreasing histone acetylation through HIF-1α-mediated HDAC3 upregulation. Our findings may provide information for further understanding of the molecular mechanisms of Nano-Ni-induced fibrosis and carcinogenesis.

PEG2-Induced Pyroptosis Regulates the Expression of HMGB1 and Promotes hEM15A Migration in Endometriosis.

Endometriosis (EMS) is a common gynecological disease. Prostaglandin E2 (PGE2), which induces chronic pelvic inflammation and cell pyroptosis, a form of programmed cell death based on inflammasome activation, are involved in EMS, but the extent of their involvement and roles remain unclear. The present study aimed to evaluate PGE2-induced pyroptosis in EMS and the influence of PGE2 in EMS progression. Using western blotting, it was found that the expressions of PGE2 and pyroptosis-related proteins (NLRP3, cleaved caspase-1, interleukin (IL)-1ß and IL-18) were higher in EMS tissues than in normal endometrial tissues. The levels of PGE2, IL-1ß, and IL-18 in the serum of patients with EMS and cell culture fluids were also detected. Using the transwell assay, we verified that PGE2 promoted hEM15A migration via the NLRP3/caspase-1 pyroptotic pathway, and PGE2-induced pyroptosis upregulated the expressions of high mobility group box 1 (HMGB1), E-cadherin, and vimentin. Immunohistochemistry analysis confirmed that PGE2-induced pyroptosis contributed to EMS invasion. These results suggest that PGE2-induced pyroptosis affects the progression of EMS by changing the migration ability of pyroptotic cells and upregulating the expression of HMGB1, E-cadherin, and vimentin. Our findings provide crucial evidence for new treatment pathways and use of anti-inflammatory drugs in EMS.

Cobalt Chloride-induced Hypoxia Can Lead SKBR3 and HEK293T Cell Lines toward Epithelial-mesenchymal Transition.

Hypoxia is a common characteristic of the tumor microenvironment. In response to hypoxia, expression of the hypoxia-inducible factor (HIF) can lead to activation of downstream molecular events such as epithelial-mesenchymal transition (EMT), invasion, and angiogenesis. In this study, CoCl2 was used to simulate hypoxia in SKBR3 and HEK293T cell lines to investigate whether this treatment can induce hypoxia-associated EMT and invasion in the studied cells. SKBR3 and HEK293T cells were treated with different concentrations of CoCl2 at different exposure times and their viability was analyzed. To confirm successful hypoxia induction, the expression levels of HIF1α and vascular endothelial growth factor A (VEGFA) mRNA were assessed. Additionally, the expression of EMT-associated markers including snail, E-cadherin, N-cadherin, and vimentin, as well as invasion-related genes including matrix metalloproteinase-2 (MMP2) and MMP9 was measured. We found that cell viability in CoCl2-treated cells was concentration-dependent and was not affected at low doses. While the expression of HIF and VEGFA genes was upregulated following hypoxia induction. E-cadherin expression was significantly downregulated in HEK293T cells; while, N-cadherin and snail were upregulated in both cell lines. Moreover, an increment of MMP expression was only observed in SKBR3 cells. Taken together, the findings indicated that CoCl2 can mimic hypoxia in both cell lines, but EMT was triggered in SKBR3 cells more effectively than in HEK293T cells, and invasion was only stimulated in SKBR3 cells. In conclusion, SKBR3 cancer cells can be used as an EMT model to better understand its control and manipulation mechanisms and to investigate new therapeutic targets for the suppression of tumor metastasis.