ESC reverses epithelial mesenchymal transition induced by transforming growth factor-β via inhibition of Smad signal pathway in HepG2 liver cancer cells

Value of biomarkers in epithelial-mesenchymal transition models of liver cancer under different interventions: a meta-analysis

Aim: A meta-analysis was conducted to evaluate the effectiveness of crucial biomarkers in HepG2 cells during epithelial-mesenchymal transformation induced by multiple interventions. Methods: PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Wan Fang Data and VIP databases were systematically searched from inception to 14 June 2020, by two independent reviewers. Results: A total of 58 studies were included in the meta-analysis. E-cadherin, N-cadherin and vimentin performed well under medicinal interventions. E-cadherin worked well under genetic interventions. E-cadherin and N-cadherin also performed significantly well under tumor microenvironment interventions. Under ncRNA interventions, the expression of E-cadherin significantly changed. Conclusion: Different sets of biomarkers should be selected under various interventions based on their performance.

4-Phenylbutyrate Mitigates the Motor Impairment and Dopaminergic Neuronal Death During Parkinson's Disease Pathology via Targeting VDAC1 Mediated Mitochondrial Function and Astrocytes Activation

Parkinson's disease (PD) is a progressive motor neurodegenerative disorder significantly associated with protein aggregation related neurodegenerative mechanisms. In view of no disease modifying drugs, the present study was targeted to investigate the therapeutic effects of pharmacological agent 4-phenylbutyric acid (4PBA) in PD pathology. 4PBA is an FDA approved monocarboxylic acid with inhibitory activity towards histone deacetylase and clinically treats urea cycle disorder. First, we observed the significant protective effects of 4PBA on PD specific neuromuscular coordination, level of tyrosine hydroxylase, α-synuclein level and neurotransmitter dopamine in both substantia nigra and striatal regions of the experimental rat model of PD. Further results revealed that treatment with 4PBA drug exhibited significant protection against disease related oxidative stress and augmented nitrite levels. The disease pathology-related depletion in mitochondrial membrane potential and augmented level of calcium as well as mitochondrion membrane located VDAC1 protein level and cytochrome-c translocation were also significantly attenuated with 4PBA administration. Inhibited neuronal apoptosis and restored neuronal morphology were also observed with 4PBA treatment as measured by level of pro-apoptotic proteins t-Bid, Bax and cleaved caspase-3 along with cresyl violet staining in both substantia nigra and striatal regions. Lastly, PD-linked astrocyte activation was significantly inhibited with 4PBA treatment. Altogether, our findings suggest that 4PBA exerts broad-spectrum neuroprotective effects in PD animal model.

Cinnamomum bejolghota Extract Inhibits Colorectal Cancer Cell Metastasis and TGF-β1-Induced Epithelial-Mesenchymal Transition via Smad and Non-Smad Signaling Pathway

Cinnamomum bejolghota, used in Thai traditional medicine remedies, has several biological activities including antimicrobial, antifungal, and anticancer. In colorectal cancer, epithelial-mesenchymal transition (EMT) is an initial step of cancer metastasis. Thus, this study investigated the effects of C. bejolghota bark extract (CBE) on colorectal cancer cell metastasis and transforming growth factor-β1 (TGF-β1) induced EMT in LoVo cells. The results showed that CBE could reduce cell migration, invasion, and adhesion of LoVo cells in a dose-dependent manner. In addition, our studies also showed that CBE could reverse TGF-β1-induced morphological changes as well as increase an epithelial marker, E-cadherin, while the expression of the mesenchymal marker, N-cadherin, was decreased in TGF-β1-treated LoVo cells. MMP-2 expression was effectively decreased but TIMP-1 and TIMP-2 expression was increased by the CBE treatment in LoVo cells. CBE also inhibited Smad2/3 phosphorylation and nuclear translocation as well as decreased the expression of Snail, Slug, and TCF8/ZEB1 transcription factors in LoVo cells. Moreover, CBE could inhibit TGF-β1-induced Smad-independent signaling pathway by decreased phosphorylation of ERK1/2, p38, and Akt. These findings suggest that CBE inhibited TGF-β1-induced EMT in LoVo cells via both Smad-dependent and Smad-independent pathways. Therefore, CBE may function as an alternative therapeutic treatment for colorectal cancer metastasis.

Drug resistance via radixin-mediated increase of P-glycoprotein membrane expression during SNAI1-induced epithelial-mesenchymal transition in HepG2 cells

OBJECTIVES

Epithelial-mesenchymal transition (EMT) plays a role in cancer metastasis as well as in drug resistance through various mechanisms, including increased drug efflux mediated by P-glycoprotein (P-gp). In this study, we investigated the activation mechanism of P-gp, including its regulatory factors, during EMT in hepatoblastoma-derived HepG2 cells.

METHODS

HepG2 cells were transfected with SNAI1 using human adenovirus serotype 5 vector. We quantified mRNA and protein expression levels using qRT-PCR and western blot analysis, respectively. P-gp activity was evaluated by uptake assay, and cell viability was assessed by an MTT assay.

KEY FINDINGS

P-gp protein expression on plasma membrane was higher in SNAI1-transfected cells than in Mock cells, although there was no difference in P-gp protein level in whole cells. Among the scaffold proteins such as ezrin, radixin and moesin (ERM), only radixin was increased in SNAI1-transfected cells. Uptake of both Rho123 and paclitaxel was decreased in SNAI1-transfected cells, and this decrease was blocked by verapamil, a P-gp inhibitor. The reduced susceptibility of SNAI1-transfected cells to paclitaxel was reversed by elacridar, another P-gp inhibitor.

CONCLUSIONS

Increased expression of radixin during SNAI1-induced EMT leads to increased P-gp membrane expression in HepG2 cells, enhancing P-gp function and thereby increasing drug resistance.

CDCA8 as an independent predictor for a poor prognosis in liver cancer

Background

Human cell division cycle associated 8 (CDCA8) a key regulator of mitosis, has been described as a potential prognostic biomarker for a variety of cancers, such as breast, colon and lung cancers. We aimed to evaluate the potential role of CDCA8 expression in the prognosis of liver cancer by analysing data from The Cancer Genome Atlas (TCGA).

Methods

The Wilcoxon rank-sum test was used to compare the difference in CDCA8 expression between liver cancer tissues and matched normal tissues. Then, we applied logistic regression and the Wilcoxon rank-sum test to identify the association between CDCA8 expression and clinicopathologic characteristics. Cox regression and the Kaplan–Meier method were used to examine the clinicopathologic features correlated with overall survival (OS) in patients from the TCGA. Gene set enrichment analysis (GSEA) was performed to explore possible mechanisms of CDCA8 according to the TCGA dataset.

Results

CDCA8 expression was higher in liver cancer tissues than in matched normal tissues. Logistic regression and the Wilcoxon rank-sum test revealed that the increased level of CDCA8 expression in liver cancer tissues was notably related to T stage (OR = 1.64 for T1/2 vs. T3/4), clinical stage (OR = 1.66 for I/II vs. III/IV), histologic grade (OR = 6.71 for G1 vs. G4) and histological type (OR = 0.24 for cholangiocarcinoma [CHOL] vs. hepatocellular carcinoma [LIHC]) (all P-values < 0.05). Kaplan–Meier survival analysis indicated that high CDCA8 expression was related to a poor prognosis in liver cancer (P = 2.456 × 10⁻⁶). Univariate analysis showed that high CDCA8 expression was associated with poor OS in liver cancer patients, with a hazard ratio (HR) of 1.85 (95% confidence interval [CI]: 1.47–2.32; P = 1.16 × 10^–7). Multivariate analysis showed that CDCA8 expression was independently correlated with OS (HR = 1.74; CI: 1.25–12.64; P = 1.27 × 10^–5). GSEA revealed that the apoptosis, cell cycle, ErbB, MAPK, mTOR, Notch, p53 and TGF-β signaling pathways were differentially enriched in the CDCA8 high expression phenotype.

Conclusions

High CDCA8 expression is a potential molecular predictor of a poor prognosis in liver cancer.

TGF-β1 mediated Smad signaling pathway and EMT in hepatic fibrosis induced by Nano NiO in vivo and in vitro

Nickel oxide nanoparticles (Nano NiO) bears hepatotoxicity, while whether it leads to liver fibrosis remains unclear. The aim of this study was to establish the Nano NiO-induced hepatic fibrosis model in vivo and investigate the roles of transforming growth factor β1 (TGF-β1) in Smad pathway activation, epithelial-mesenchymal transition (EMT) occurrence, and extracellular matrix (ECM) deposition in vitro. Male Wistar rats were exposed to 0.015, 0.06, and 0.24 mg/kg Nano NiO by intratracheal instilling twice a week for 9 weeks. HepG2 cells were treated with 100 μg/mL Nano NiO and TGF-β1 inhibitor (SB431542) to explore the mechanism of collagen formation. Results of Masson staining as well as the elevated levels of type I collagen (Col-I) and Col-III suggested that Nano NiO resulted in hepatic fibrosis in rats. Furthermore, Nano NiO increased the protein expression of TGF-β1, p-Smad2, p-Smad3, alpha-smooth muscle actin (α-SMA), matrix metalloproteinase9 (MMP9), and tissue inhibitors of metalloproteinase1 (TIMP1), while decreased the protein content of E-cadherin and Smad7 in rat liver and HepG2 cells. Most importantly, Nano NiO-triggered the abnormal expression of the abovementioned proteins were all alleviated by co-treatment with SB431542, implying that TGF-β1-mediated Smad pathway, EMT and MMP9/TIMP1 imbalance were involved in overproduction of collagen in HepG2 cells. In conclusion, these findings indicated that Nano NiO induced hepatic fibrosis via TGF-β1-mediated Smad pathway activation, EMT occurrence, and ECM deposition.

The Telocytes in the Subepicardial Niche

A great interest has developed over the last several years in research on interstitial Cajal-like cells (ICLCs), later renamed to telocytes (TCs). Such studies are restricted by diverse limitations. We aimed to critically review (sub)epicardial ICLCs/TCs and to bring forward supplemental immunohistochemical evidence on (sub)epicardial stromal niche inhabitants. We tested the epicardial expressions of CD117/c-kit, CD34, Cytokeratin 7 (CK7), Ki67, Platelet-Derived Growth Factor Receptor (PDGFR)-α and D2-40 in adult human cardiac samples. The mesothelial epicardial cells expressed D2-40, CK7, CD117/c-kit and PDGFR-α. Subepicardial D2-40-positive lymphatic vessels and isolated D2-40-positive and CK7-positive subepicardial cells were also found. Immediate submesothelial spindle-shaped cells expressed Ki-67. Submesothelial stromal cells and endothelial tubes were PDGFR-α-positive and CD34-positive. The expression of CD34 was pan-stromal, so a particular stromal cell type could not be distinguished. The stromal expression of CD117/c-kit was also noted. It seems that epicardial TCs could not be regarded as belonging to a unique cell type until (pre)lymphatic endothelial cells are inadequately excluded. Markers such as CD117/c-kit or CD34 seem to be improper for identifying TCs as a distinctive cell type. Care should be taken when using the immunohistochemical method and histological interpretations, as they may not produce accurate results.

Isoviolanthin Extracted from Dendrobium officinale Reverses TGF-β1-Mediated Epithelial⁻Mesenchymal Transition in Hepatocellular Carcinoma Cells via Deactivating the TGF-β/Smad and PI3K/Akt/mTOR Signaling Pathways

Dendrobium officinale is a precious medicinal herb and health food, and its pharmacological actions have been studied and proved. However, the mechanisms by which its active flavonoid glycosides affect epithelial⁻mesenchymal transition (EMT) in hepatocellular carcinoma (HCC) cells, such as HepG2 and Bel-7402 cells, have not been previously investigated. Therefore, we investigated whether isoviolanthin extracted from the leaves of Dendrobium officinale inhibits transforming growth factor (TGF)-β1-induced EMT in HCC cells. In this study, the physicochemical properties and structure of isoviolanthin were identified by HPLC, UV, ESIMS, and NMR and were compared with literature data. HCC cells were pretreated with 10 ng/mL TGF-β1 to induce EMT and then treated with isoviolanthin. Herein, we found that isoviolanthin exhibited no cytotoxic effects on normal liver LO2 cells but notably reduced the migratory and invasive capacities of TGF-β1-treated HCC cells. Additionally, isoviolanthin treatment decreased matrix metalloproteinase (MMP)-2 and -9 levels, and remarkably altered the expression of EMT markers via regulating the TGF-β/Smad and PI3K/Akt/mTOR signaling pathways; Western blot analysis confirmed that the effects of the inhibitors SB431542 and LY294002 were consistent with those of isoviolanthin. These findings demonstrate the potential of isoviolanthin as a therapeutic agent for the treatment of advanced-stage metastatic HCC.

Extract of Stellerachamaejasme L(ESC) inhibits growth and metastasis of human hepatocellular carcinoma via regulating microRNA expression

BACKGROUND

MicroRNAs(miRNAs)are involved in the initiation and progression of hepatocellular carcinoma. ESC, an extract of Stellerachamaejasme L, had been confirmed as a potential anti-tumor extract of Traditional Chinese Medicine. In light of the important role of miRNAs in hepatocellular carcinoma, we questioned whether the inhibitory effects of ESC on hepatocellular carcinoma (HCC) were associated with miRNAs.

METHODS

The proliferation inhibition of ESC on HCC cells was measured with MTT assay. The migration inhibition of ESC on HCC cells was measured with transwell assay. The influences of ESC on growth and metastasis inhibition were evaluated with xenograft tumor model of HCC. Protein expressions were measured with western blot and immunofluorescence methods and miRNA profiles were detected with miRNA array. Differential miRNA and target mRNAs were verified with real-time PCR.

RESULTS

The results showed that ESC could inhibit proliferation and epithelial mesenchymal transition (EMT) in HCC cells in vitro and tumor growth and metastasis in xenograft models in vivo. miRNA array results showed that 69 differential miRNAs in total of 429 ones were obtained in MHCC97H cells treated by ESC. hsa-miR-107, hsa-miR-638, hsa-miR-106b-5p were selected to be validated with real-time PCR method in HepG2 and MHCC97H cells. Expressions of hsa-miR-107 and hsa-miR-638 increased obviously in HCC cells treated by ESC. Target genes of three miRNAs were also validated with real-time PCR. Interestingly, only target genes of hsa-miR-107 changed greatly. ESC downregulated the MCL1, SALL4 and BCL2 gene expressions significantly but did not influence the expression of CACNA2D1.

CONCLUSION

The findings suggested ESC regressed growth and metastasis of human hepatocellular carcinoma via regulating microRNAs expression and their corresponding target genes.

Oxymatrine protects against the effects of cardiopulmonary resuscitation via modulation of the TGF-β1/Smad3 signaling pathway

Previous studies have demonstrated that oxymatrine may inhibit ventricular remodeling and serves an important role in the treatment of cardiovascular disease. The present study investigated whether oxymatrine treatment protects against the effects of cardiopulmonary resuscitation (CPR) via regulation of the transforming growth factor‑β1 (TGF‑β1)/mothers against decapentaplegic (Smad) signaling pathway. A CPR model was established in Sprague‑Dawley (SD) rats by asphyxiation, and rats were subsequently anaesthetized by intraperitoneal injection of chloral hydrate. SD rats were then administered 25 or 50 mg/kg oxymatrine once a day for 4 weeks. Oxymatrine treatment significantly improved troponin I levels, the ejection fraction, hydroxyproline content and the myocardial performance index in model rats. However, treatment with oxymatrine significantly reduced arterial oxygen tension, arterial lactate levels and oxygen extraction. Treatment with oxymatrine following CPR significantly inhibited the protein expression levels of TGF‑β1, TGF‑β1 receptor type 1 and Smad homolog 3 (Smad3) in model rats. The results of this research indicated that oxymatrine treatment may protect against the effects of CPR via regulation of the TGF‑β1/Smad3 signaling pathway and may be a novel drug for CPR in a clinical setting.

Methyl-CpG-binding domain 3 inhibits epithelial-mesenchymal transition in pancreatic cancer cells via TGF-β/Smad signalling

BACKGROUND

Methyl-CpG-binding domain 3 (MBD3) is an aberrant expression in human malignancies. However, the role of MBD3 in pancreatic cancer progression remains to be clarified. In this study, we investigated the effects of MBD3 on the epithelial-mesenchymal transition (EMT), and the underlying mechanism in pancreatic cancer cells.

METHODS

The abilities of migration and invasion were examined by transwell and BD Matrigel invasion assays. EMT and TGF-β/Smad signalling were evaluated.

RESULTS

First, we find that MBD3 expression is lower in pancreatic cancer tissues than that in non-tumour tissues, and patients with lower MBD3 levels survive significantly less than those with higher levels. Subsequently, we find that MBD3 knockdown promotes the abilities of migration and invasion, while MBD3 overexpression inhibits the above abilities. Also, MBD3 knockdown remarkably increases mesenchymal markers expression of Vimentin, α-SMA, Snail, N-cadherin, β-catenin, and downregulates epithelial markers expression of E-cadherin. On the contrary, MBD3 overexpression results in the opposite effects. Further evidence reveals that MBD3 knockdown up-regulates expression of TGF-β, and then activates p-Smad2 and p-Smad3, while MBD3 overexpression results in downregulation of TGF-β, p-Smad2, and p-Smad3.

CONCLUSIONS

MBD3 inhibits EMT in pancreatic cancer cells probably via TGF-β/Smad signalling, and may be a new candidate target for diagnostics and prognosis of pancreatic cancer.

Effect of RhoC on the epithelial-mesenchymal transition process induced by TGF-β1 in lung adenocarcinoma cells

According to recent research, Ras homolog gene family member C (RhoC) is confirmed to have a powerful regulatory effect on cell motility mediated by the cytoskeleton, and this process is closely associated with tumor invasion and metastasis. In addition, the epithelial-mesenchymal transition (EMT) process which causes cytoskeleton rearrangement, also plays a pivotal role in tumor invasion and metastasis.Consequently, in the present study, we aimed to ascertain whether RhoC has an effect on the EMT process induced by TGF-β1 in lung adenocarcinoma cells and whether RhoC promotes tumor invasion by mediating the occurrence of EMT. Based on the findings, we demonstrated that RhoC was an essential mediator of the EMT process in lung adenocarcinoma cell line A549 which was evaluated by observing the morphological characteristics of the cells and by assessing the expression levels of two EMT marker proteins: E-cadherin and vimentin. During the process of EMT in the A549 cells induced by TGF-β1 (5 ng/ml), upregulated RhoC protein and RhoC activity were detected, which was associated with the enhanced invasive capability of the cells in vitro. Conversely, downregulation of the expression of RhoC by shRNA markedly impeded EMT progression as well as the invasion of A549 cells. Our results may provide a novel target towards the prevention of metastasis in advanced lung adenocarcinoma.