Cathepsin V is correlated with the prognosis and tumor microenvironment in liver cancer.

Recent studies have shown that high cell cycle activity negatively correlates with antitumor immunity in certain cancer types. However, a similar correlation has not been proven in liver cancer. We downloaded transcriptomic profiles of the cancer genome atlas-liver hepatocellular carcinoma (TCGA-LIHC) and assessed the cell cycle distribution of samples using single sample gene set enrichment analysis (ssGSEA), termed the cell cycle score (CCS). We obtained cell cycle-related differentially expressed prognostic genes and identified CENPA, CDC20, and CTSV using LASSO regression. We studied the effect of CTSV on clinical features and immune alterations in liver cancer based on TCGA-LIHC data. In vitro and in vivo experiments were performed to validate the role of CTSV in liver cancer using liver cancer cell lines and tissues. We found that the CCS closely correlated with the clinical features and prognosis of patients in TCGA-LIHC. Analysis of differentially expressed genes (DEGs), univariate Cox regression, and least absolute shrinkage and selection operator (LASSO) regression identified cathepsin V (CTSV) with prognostic significance in LIHC. Importantly, single-gene survival analysis of CTSV using microarray and sequencing data indicated that high levels of CTSV expression correlated with an unfavorable prognosis in various cancers. Gene set enrichment analysis revealed that high CTSV expression closely correlated with decreased expression of metabolic genes and increased expression of cell cycle genes. Furthermore, difference and correlation analyses of the relationship between CTSV expression and immune infiltrates, determined using CIBERSORT and TIMER algorithms, revealed that CTSV expression correlated with macrophages and CD4+ T cells. In vitro and in vivo experiments revealed that knockdown of CTSV inhibited liver cancer cells proliferation. Immunohistochemical staining showed that high CTSV expression correlated with macrophage infiltration in liver cancer tissues, predicted a poor prognosis, and is associated with the effectiveness of hepatocellular carcinoma treatment. In couclusion, CTSV is a novel cell cycle-associated gene with clinical significance in HCC.

Sustained ameliorating effects and autonomic mechanisms of transcutaneous electrical acustimulation at ST36 in patients with chronic constipation.

Background and aims: The treatment of chronic constipation is still a great challenge in clinical practice. This study aimed to determine the efficacy and sustained effects of transcutaneous electrical acustimulation (TEA) at acupoint ST36 on the treatment of chronic constipation and explore possible underlying mechanisms. Methods: Forty-four patients with chronic constipation were recruited and randomly assigned to a TEA group or sham-TEA group. A bowel diary was recorded by the patients. The Patient Assessment of Constipation Symptom (PAC-SYM) and the Patient Assessment of Constipation Quality of Life (PAC-QoL) questionnaires were administered during each visit. Anal and rectal functions were evaluated with anorectal manometry. Autonomic functions were assessed by the special analysis of heart rate variability derived from the ECG recording. Results: Compared with sham-TEA, 2-week TEA treatment significantly increased the number of spontaneous bowel movements (SBMs) (5.64 ± 0.54 vs. 2.82 ± 0.36, P < 0.001) and lowered the total scores of PAC-SYM (0.90 ± 0.14 vs. 1.35 ± 0.13, P < 0.001) and PAC-QoL (0.89 ± 0.13 vs. 1.32 ± 0.14, P < 0.05). TEA improved symptoms, as reflected by a reduction in the straining (P < 0.001), the incomplete defecation (P < 0.05), the frequency of emergency drug use (P < 0.05), the days of abdominal distension (P < 0.01) and an increase in intestinal satisfaction (P < 0.01). Interestingly, the effects of TEA on the improvement of weekly SBMs sustained four weeks after the cessation of treatment (P < 0.001). Anorectal manometry indicated that 2-week treatment of TEA lowered the threshold of first sensation (P < 0.05), desire of defecation (P < 0.01) and maximum tolerable volume (P < 0.001) compared with sham-TEA group. TEA also significantly enhanced vagal activity, reflected by high-frequency band of heart rate variability, compared with sham-TEA (57.86 ± 1.83 vs. 48.51 ± 2.04, P < 0.01). Conclusion: TEA ameliorates constipation with sustained effects, which may be mediated via improvement of rectal sensitivity and enhancement of vagal activity. Clinical trial registration: [https://clinicaltrials.gov/], identifier [ChiCTR210004267].

The effect of neoadjuvant chemotherapy on the tumor immune microenvironment in gastrointestinal tumors.

In recent years, numerous studies have demonstrated that the tumor immune microenvironment (TIME) is capable of regulating the growth of tumors, and tumor-infiltrating immune cells in the TIME can affect the prognosis and treatment responses of patients. Consequently, therapies targeting these immune cells have emerged as important antitumor treatments. As a crucial componet of the perioperative treatment of malignant tumors, neoadjuvant chemotherapy (NACT) can improve the surgical resection rate and prognosis of patients and is a suitable clinical model to evaluate the effect of chemotherapy on the TIME. To provide a rationale for developing valid combinational therapies, this review summarizes the impact of NACT on the TIME, the relationship between tumor-infiltrating immune cells and treatment responses of patients, and the prognostic value of these infiltrating immune cells.

Effects of Low-dose and High-dose Rifaximin in the Treatment of Covert Hepatic Encephalopathy.

Background and Aims: Rifaximin is effective in preventing and treating hepatic encephalopathy (HE). This study aimed to investigate the efficacy and safety of different dosages of rifaximin in the treatment of cirrhotic patients with covert HE (CHE). Methods: In this single-center, randomized, controlled, open-label study, CHE was diagnosed using a combination of the psychometric HE score and the EncephalApp Stroop test. Cirrhotic patients with CHE were recruited and randomly assigned to low-dose rifaximin 800 mg/day, high-dose rifaximin (1,200 mg/day), and control groups, and were treated for 8 weeks. The sickness impact profile (SIP) scale was used to evaluate the health-related quality of life (HRQOL) of patients. Forty patients were included in the study, 12 were assigned to the low-dose group, 14 to the high-dose group, and 14 patients to the control group. Results: The percentage of patients with CHE reversal was significantly higher in both the low-dose (41.67%, 5/12) and high-dose (57.14%, 8/14) groups than in the control group (7.14%, 1/14) at 8 weeks (p=0.037 and p=0.005, respectively). In addition, both doses of rifaximin resulted in significant improvement of the total SIP score compared with the control group. There were no significant differences in the CHE reversal rate, total SIP score improvement, and incidence of adverse event between the low-dose and high-dose groups (p>0.05). Conclusions: Low-dose rifaximin reverses CHE and improves HRQOL in cirrhotic patients with comparable effects and safety to high-dose rifaximin.

Transcutaneous Electrical Acustimulation Ameliorates Motion Sickness Induced by Rotary Chair in Healthy Subjects: A Prospective Randomized Crossover Study.

OBJECTIVES: Motion sickness (MS) is a common physiological response to real or virtual motion. The purpose of this study was to investigate the effects of transcutaneous electrical acustimulation (TEA) on MS and the underlying mechanisms in healthy subjects. MATERIALS AND METHODS: A total of 50 healthy participants were recruited and randomly assigned into two groups to complete two separate sessions in a crossover study. A Coriolis rotary chair was used as a model to provoke severe MS. The total tolerable rotation time and Graybiel scoring scale were recorded. Gastric slow waves were detected by electrogastrogram. The autonomic nervous function, including the vagal activity, was evaluated by the analysis of heart rate variability derived from the electrocardiogram recording. The serum levels of arginine vasopressin (AVP) and norepinephrine (NE) were examined. RESULTS: Of note, 22 participants in TEA and only 11 participants in the sham-TEA session completed the entire five-rotation MS stimuli (p = 0.019). TEA significantly prolonged the total tolerable rotation time of MS stimuli (220.4 ± 11.59 vs 173.6 ± 12.3 seconds, p < 0.001) and lowered MS symptom scores (12.56 ± 2.03 vs 22.06 ± 3.0, p < 0.001). TEA improved the percentage of normal gastric slow waves, compared with sham-TEA (56.0 ± 2.1% vs 51.6 ± 2.0%, p = 0.033). TEA also significantly enhanced vagal activity compared with sham-TEA (0.41 ± 0.02 vs 0.31 ± 0.02, p < 0.001). In addition, the increased serum levels of AVP and NE on MS stimulation were markedly suppressed by TEA treatment, compared with sham-TEA (AVP, 56.791 ± 4.057 vs 79.312 ± 10.036 ng/mL, p = 0.033; NE, 0.388 ± 0.037 vs 0.501 ± 0.055 ng/mL, p = 0.021). CONCLUSIONS: Needleless TEA is a potent therapeutic approach for severe MS, as it increases participants' tolerance and ameliorates MS symptoms, which may be attributed to the integrative effects of TEA on autonomic functions and neuroendocrine balance.

m6A RNA methylation-mediated HNF3γ reduction renders hepatocellular carcinoma dedifferentiation and sorafenib resistance.

Hepatocyte nuclear factor 3γ (HNF3γ) is a hepatocyte nuclear factor, but its role and clinical significance in hepatocellular carcinoma (HCC) remain unclear. Herein, we report that HNF3γ expression is downregulated in patient HCC and inversely correlated with HCC malignancy and patient survival. Moreover, our data suggested that the HNF3γ reduction in HCC could be mediated by METTL14-dependent m6A methylation of HNF3γ mRNA. HNF3γ expression was increased during hepatic differentiation and decreased in dedifferentiated HCC cells. Interestingly, HNF3γ delivery promoted differentiation of not only HCC cells but also liver CSCs, which led to suppression of HCC growth. Mechanistic analysis suggested an HNF3γ-centered regulatory network that includes essential liver differentiation-associated transcription factors and functional molecules, which could synergistically facilitate HCC cell differentiation. More importantly, enforced HNF3γ expression sensitized HCC cells to sorafenib-induced growth inhibition and cell apoptosis through transactivation of OATP1B1 and OATP1B3 expression, which are major membrane transporters for sorafenib uptake. Clinical investigation showed that patient-derived HCC xenografts with high HNF3γ expression exhibited a sorafenib response and patients with high HCC HNF3γ levels benefited from sorafenib therapy. Together, these results suggest that HNF3γ plays an essential role in HCC differentiation and may serve as a therapeutic target and predictor of sorafenib benefit in patients.

Ameliorating Effects and Autonomic Mechanisms of Transcutaneous Electrical Acustimulation in Patients With Gastroesophageal Reflux Disease.

BACKGROUND/AIM: Gastric dysmotility is one of pathophysiologies of gastroesophageal reflux disease (GERD). The aim of this study was to investigate the effects of transcutaneous electrical acustimulation (TEA) on gastric accommodation and gastric slow waves, and evaluate possible mechanisms in patients with GERD. METHODS: Thirty patients were studied in two randomized sessions of sham-TEA and TEA with the measurements of esophageal high-resolution manometry (HRM), gastric accommodation assessed by a nutrient-drinking test, electrogastrogram (EGG), electrocardiogram (ECG), and postprandial dyspeptic symptoms. RESULTS: Compared with sham-TEA, TEA improved nutrient drinking-induced fullness (42.0 ± 3.3 vs. 31.0 ± 3.5, P = 0.003) at 10 min after the drink, and belching right after the drink (22.0 ± 4.6 vs. 11.7 ± 3.1, P = 0.012) and at 10 min (16.0 ± 3.8 vs. 3.0 ± 1.5, P = 0.002) after the drink. TEA also improved gastric accommodation (954 ± 37 mL vs. 857 ± 47 mL, P = 0.001) and normalized maximal drink-induced impairment in gastric slow waves. Concurrently, TEA enhanced vagal activity assessed from spectral analysis of heart rate variability in the postprandial state (0.42 ± 0.03 vs. 0.49 ± 0.04, P = 0.039). The vagal activity was positively correlated with the percentage of normal slow waves (r = 0.528; P = 0.003) and negatively correlated with the regurgitation score (r = -0.408, P = 0.025). CONCLUSIONS: Acute TEA increases gastric accommodation, improves gastric slow waves, and reduces postprandial fullness and belching, possibly mediated via the vagal mechanisms.

Conversion of hepatoma cells to hepatocyte-like cells by defined hepatocyte nuclear factors.

Normal cells become cancer cells after a malignant transformation, but whether cancer cells can be reversed to normal status remains elusive. Here, we report that the combination of hepatocyte nuclear factor 1A (HNF1A), HNF4A and forkhead box protein A3 (FOXA3) synergistically reprograms hepatocellular carcinoma (HCC) cells to hepatocyte-like cells (reprogrammed hepatocytes, rHeps). Our results show that rHeps lose the malignant phenotypes of cancer cells and retrieve hepatocyte-specific characteristics including hepatocyte-like morphology; global expression pattern of genes and specific biomarkers of hepatocytes; and the unique hepatic functions of albumin (ALB) secretion, glycogen synthesis, low-density lipoprotein (LDL) uptake, urea production, cytochrome P450 enzymes induction and drug metabolism. Intratumoral injection of these three factors efficiently shrank patient-derived tumor xenografts and reprogrammed HCC cells in vivo. Most importantly, transplantation of rHeps in the liver of fumarylacetoacetate hydrolase-deficient (Fah-/-) mice led to the reconstruction of hepatic lobules and the restoration of hepatic function. Mechanistically, exogenous expression of HNF1A, HNF4A and FOXA3 in HCC cells initiated the endogenous expression of numerous hepatocyte nuclear factors, which promoted the conversion of HCC cells to hepatocyte-like cells. Collectively, our results indicate the successful conversion of hepatoma cells to hepatocyte-like cells, not only extending our current knowledge of cell reprogramming but also providing a route towards a novel therapeutic strategy for cancer.

The HLF/IL-6/STAT3 feedforward circuit drives hepatic stellate cell activation to promote liver fibrosis.

BACKGROUND AND AIMS: Liver fibrosis is a wound-healing response that disrupts the liver architecture and function by replacing functional parenchyma with scar tissue. Recent progress has advanced our knowledge of this scarring process, but the detailed mechanism of liver fibrosis is far from clear. METHODS: The fibrotic specimens of patients and HLF (hepatic leukemia factor)PB/PB mice were used to assess the expression and role of HLF in liver fibrosis. Primary murine hepatic stellate cells (HSCs) and human HSC line Lx2 were used to investigate the impact of HLF on HSC activation and the underlying mechanism. RESULTS: Expression of HLF was detected in fibrotic livers of patients, but it was absent in the livers of healthy individuals. Intriguingly, HLF expression was confined to activated HSCs rather than other cell types in the liver. The loss of HLF impaired primary HSC activation and attenuated liver fibrosis in HLFPB/PB mice. Consistently, ectopic HLF expression significantly facilitated the activation of human HSCs. Mechanistic studies revealed that upregulated HLF transcriptionally enhanced interleukin 6 (IL-6) expression and intensified signal transducer and activator of transcription 3 (STAT3) phosphorylation, thus promoting HSC activation. Coincidentally, IL-6/STAT3 signalling in turn activated HLF expression in HSCs, thus completing a feedforward regulatory circuit in HSC activation. Moreover, correlation between HLF expression and alpha-smooth muscle actin, IL-6 and p-STAT3 levels was observed in patient fibrotic livers, supporting the role of HLF/IL-6/STAT3 cascade in liver fibrosis. CONCLUSIONS: In aggregate, we delineate a paradigm of HLF/IL-6/STAT3 regulatory circuit in liver fibrosis and propose that HLF is a novel biomarker for activated HSCs and a potential target for antifibrotic therapy.

Chronic inflammation-elicited liver progenitor cell conversion to liver cancer stem cell with clinical significance.

The substantial heterogeneity and hierarchical organization in liver cancer support the theory of liver cancer stem cells (LCSCs). However, the relationship between chronic hepatic inflammation and LCSC generation remains obscure. Here, we observed a close correlation between aggravated inflammation and liver progenitor cell (LPC) propagation in the cirrhotic liver of rats exposed to diethylnitrosamine. LPCs isolated from the rat cirrhotic liver initiated subcutaneous liver cancers in nonobese diabetic/severe combined immunodeficient mice, suggesting the malignant transformation of LPCs toward LCSCs. Interestingly, depletion of Kupffer cells in vivo attenuated the LCSC properties of transformed LPCs and suppressed cytokeratin 19/Oval cell 6-positive tumor occurrence. Conversely, LPCs cocultured with macrophages exhibited enhanced LCSC properties. We further demonstrated that macrophage-secreted tumor necrosis factor-α triggered chromosomal instability in LPCs through the deregulation of ubiquitin D and checkpoint kinase 2 and enhanced the self-renewal of LPCs through the tumor necrosis factor receptor 1/Src/signal transducer and activator of transcription 3 pathway, which synergistically contributed to the conversion of LPCs to LCSCs. Clinical investigation revealed that cytokeratin 19/Oval cell 6-positive liver cancer patients displayed a worse prognosis and exhibited superior response to sorafenib treatment. CONCLUSION: Our results not only clarify the cellular and molecular mechanisms underlying the inflammation-mediated LCSC generation but also provide a molecular classification for the individualized treatment of liver cancer. (Hepatology 2017;66:1934-1951).

Cancer-associated fibroblasts promote hepatocellular carcinoma metastasis through chemokine-activated hedgehog and TGF-ß pathways.

Fibroblasts are rich in the surrounding microenvironment of hepatocellular carcinoma (HCC) because most HCCs occur in fibrotic or cirrhotic livers. However, the role of cancer-associated fibroblasts (CAFs) in HCC metastasis remains obscure. Here, we reported that CAFs promote the migration and invasion of HCC cells in vitro and facilitate the HCC metastasis to the bone, brain and lung in NOD/SCID mice. The RayBio human chemokine antibody array revealed that CAFs secret higher levels of CCL2, CCL5, CCL7 and CXCL16 than peri-tumor fibroblasts. CCL2 and CCL5 increase the migration but not the invasion of HCC cells, while CCL7 and CXCL16 promote both migration and invasion of HCC cells. Moreover, CCL2 and CCL5 stimulate the activation of the hedgehog (Hh) pathway, while CCL7 and CXCL16 enhance the activity of the transforming growth factor-ß (TGF-ß) pathway in HCC cells. The neutralizing antibodies of chemokines notably attenuate the effect of CAFs on HCC metastasis and compromised the activation of Hh and TGF-ß pathways in HCC cells. In summary, CAF-secreted CCL2, CCL5, CCL7 and CXCL16 promote HCC metastasis through the coordinate activation of Hh and TGF-ß pathways in HCC cells.

Long non-coding RNA DILC regulates liver cancer stem cells via IL-6/STAT3 axis.

BACKGROUND & AIMS: Emerging evidence has demonstrated the aberrant expression of long non-coding RNAs (lncRNAs) in various malignancies including HCC. However, the knowledge of cancer stem cell-related lncRNAs remains limited. METHODS: lnc-DILC (lncRNA downregulated in liver cancer stem cells (LCSCs)) was identified by microarray and validated by real-time PCR. The role of lnc-DILC in LCSCs was assessed both in vitro and in vivo. Pull down assay and oligoribonucleotides or oligodeoxynucleotides treatment were conducted to evaluate the interaction between lnc-DILC and interleukin-6 (IL-6) promoter. RESULTS: Depletion of lnc-DILC markedly enhanced LCSC expansion and facilitated HCC initiation and progression, whereas ectopic expression of lnc-DILC dramatically inhibited LCSC expansion. Mechanistically, lnc-DILC inhibited the autocrine IL-6/STAT3 signaling. The putative binding locus of lnc-DILC within IL-6 promoter was confirmed by pull down assay. Consistently, the oligoribonucleotide mimics and an oligodeoxynucleotide decoy of lnc-DILC abrogated the effects on IL-6 transcription, STAT3 activation and LCSC expansion triggered by lnc-DILC depletion and lnc-DILC overexpression. Moreover, our data suggested that lnc-DILC mediated the crosstalk between TNF-α/NF-κB signaling and IL-6/STAT3 cascade. Clinical investigation demonstrated the reduction of lnc-DILC in patient HCCs, and suggested the correlation between lnc-DILC levels and IL-6, EpCAM or CD24 expression. Decreased lnc-DILC expression in HCCs predicts early recurrence and short survival of patients, highlighting its prognostic value. CONCLUSIONS: lnc-DILC mediates the crosstalk between TNF-α/NF-κB signaling and autocrine IL-6/STAT3 cascade and connects hepatic inflammation with LCSC expansion, suggesting that lnc-DILC could be not only a potential prognostic biomarker, but also a possible therapeutic target against LCSCs.

MicroRNA-370 Attenuates Hepatic Fibrogenesis by Targeting Smoothened.

BACKGROUND AND AIMS: Recent research shows that abnormal expression of microRNA plays an important role in the process of hepatic fibrosis . miR-370 has been reported to be involved in liver function and is suppressed during hepatic carcinogenesis. The aim of this study was to investigate the role of miR-370 in hepatic fibrosis. METHODS: The expression levels of miR-370 in rat fibrotic livers and activated hepatic stellate cells (HSCs) were evaluated by quantitative real-time PCR. The effect of miR-370 on the activation of HSCs was analyzed by flow cytometric analyses, real-time PCR and Western blot. Adenovirus carrying miR-370 was injected through the tail vein to access the effect of miR-370 on hepatic fibrosis induced by CCl4 in rats. The downstream targets of miR-370 were predicted by the Target Scan database and verified by luciferase assays, real-time PCR and Western blot in HSCs and were further confirmed by immunohistochemistry in vivo. RESULTS: Real-time PCR showed that miR-370 expression was significantly reduced in rat fibrotic livers and TGFß1-stimulated HSCs. Overexpression of miR-370 inhibited the proliferation of HSC-T6 cells via inducing cell apoptosis and suppressed the activation of HSCs. Upregulation of miR-370 obviously attenuated the CCl4-induced liver fibrosis in rats. miR-370 was directly bound to the 3'UTR of Smoothened (SMO) and suppressed the expression of SMO in HSCs and fibrotic livers. CONCLUSIONS: Our study demonstrated that miR-370 plays an inhibitory role in hepatic fibrogenesis by targeting SMO. Restoration of miR-370 may have beneficial effects on the treatment of liver fibrosis.

The transcription factor FOXA2 suppresses gastric tumorigenesis in vitro and in vivo.

BACKGROUND AND AIMS: The transcription factor forkhead box A2 (FOXA2) plays a central role in the development of endoderm-derived organs. It has been reported that FOXA2 acts as a suppressor in many kinds of tumor. However, little is known about the role of FOXA2 in gastric cancer. METHODS: The expression of FOXA2 in gastric cancer tissue samples from 89 patients was assessed by immunohistochemistry, and the clinicopathological characteristics of the samples were analyzed. The human gastric cancer cell line, BGC-823, was used to investigate the effects of FOXA2 in gastric cancer in vitro and in vivo and the potential mechanism involved was explored. RESULTS: FOXA2 expression in human gastric cancer cell lines and human gastric cancer tissues was lower compared with the normal gastric epithelium cell line GES1 and normal adult gastric tissues, respectively. Patients with high FOXA2 expression level had longer 5-year overall survival than those with low FOXA2 expression level. FOXA2 markedly inhibited growth of BGC-823 cells accompanied with the cell cycle arrest and apoptosis. Infection of BGC-823 cells by FOXA2 lentivirus resulted in reduced cell tumorigenesis in vitro and in vivo. Moreover, expression of Mucin 5AC was up-regulated along with increased expression of exogenous FOXA2 in BGC-823 cells; in contrast, dedifferentiation markers, BMI, CD54 and CD24, were down-regulated. CONCLUSIONS: These results suggest that FOXA2 induces the differentiation of gastric cancer and highlight FOXA2 as a novel therapeutic target and prognostic marker for human gastric cancer.

MicroRNA-155 attenuates activation of hepatic stellate cell by simultaneously preventing EMT process and ERK1 signalling pathway.

BACKGROUND & AIMS: Epithelial-mesenchymal transition (EMT) process and extracellular signal-regulated kinase 1 (ERK1) signalling pathway play pivotal roles in hepatic stellate cell (HSC) activation, which is associated with the altered expression patterns of microRNAs (miRNAs). miR-155 is considered a typical multifunctional miRNA to regulate many biological processes. However, little attention has been given to the contributions of miR-155 to simultaneous regulation of EMT process and ERK1 pathway during HSC activation. METHODS: Differential expression of miR-155 was assessed in activated HSC, sera and liver tissues from cirrhotic patients. Whether miR-155 could directly interact with 3'-untranslated region (3'-UTR) of T cell factor 4 (TCF4) and angiotensin II receptor type 1 (AGTR1) respectively was detected by luciferase reporter assay. The effects of enhanced miR-155 on EMT process and ERK1 pathway, cell apoptosis in HSC activation were also evaluated. RESULTS: A significant decrease in miR-155 expression was observed in activated HSC, sera or liver tissues of cirrhotic patients. MiR-155 was found to simultaneously interact with 3'-UTR of TCF4 and AGTR1 mRNAs, which are known as important regulators associated with EMT and ERK1 pathway repectively. Inhibiting miR-155 expression could stimulate the EMT state and ERK1 pathway activity, thus contributing to HSC activation. Forced miR-155 expression markedly decreased the mesenchymal markers and phosphorylated ERK1 level, and enhanced E-cadherin expression, leading to the synchronous inhibitory effect on EMT and ERK1 pathway and inducing HSC apoptosis. CONCLUSIONS: Our results implicate that miR-155 plays an important role in regulating the pathological network involving EMT process and ERK1 pathway during HSC activation.

MiR-21 simultaneously regulates ERK1 signaling in HSC activation and hepatocyte EMT in hepatic fibrosis.

BACKGROUND: MicroRNA-21 (miR-21) plays an important role in the pathogenesis and progression of liver fibrosis. Here, we determined the serum and hepatic content of miR-21 in patients with liver cirrhosis and rats with dimethylnitrosamine-induced hepatic cirrhosis and examined the effects of miR-21 on SPRY2 and HNF4α in modulating ERK1 signaling in hepatic stellate cells (HSCs) and epithelial-mesenchymal transition (EMT) of hepatocytes. METHODS: Quantitative RT-PCR was used to determine miR-21 and the expression of SPRY2, HNF4α and other genes. Immunoblotting assay was carried out to examine the expression of relevant proteins. Luciferase reporter assay was performed to assess the effects of miR-21 on its predicted target genes SPRY2 and HNF4α. Primary HSCs and hepatocytes were treated with miR-21 mimics/inhibitors or appropriate adenoviral vectors to examine the relation between miR-21 and SPRY2 or HNF4α. RESULTS: The serum and hepatic content of miR-21 was significantly higher in cirrhotic patients and rats. SPRY2 and HNF4α mRNA levels were markedly lower in the cirrhotic liver. MiR-21 overexpression was associated with enhanced ERK1 signaling and EMT in liver fibrosis. Luciferase assay revealed suppressed SPRY2 and HNF4α expression by miR-21. Ectopic miR-21 stimulated ERK1 signaling in HSCs and induced hepatocyte EMT by targeting SPRY2 or HNF4α. Downregulating miR-21 suppressed ERK1 signaling, inhibited HSC activation, and blocked EMT in TGFß1-treated hepatocytes. CONCLUSIONS: MiR-21 modulates ERK1 signaling and EMT in liver fibrosis by regulating SPRY2 and HNF4α expression. MiR-21 may serve as a potentially biomarker as well as intervention target for hepatic cirrhosis.

FOXA2 suppresses the metastasis of hepatocellular carcinoma partially through matrix metalloproteinase-9 inhibition.

The forkhead box transcription factor A2 (FOXA2) is a member of the hepatocyte nuclear factor family and plays an important role in liver development and metabolic homeostasis, but its role in the metastasis of hepatocellular carcinoma (HCC) has not been evaluated. In this study, we found that the expression of FOXA2 was decreased in 68.1% (49/72) of human HCC tissues compared with their paired non-cancerous adjacent tissues. Clinicopathological analysis revealed that reduced FOXA2 expression was correlated with aggressive characteristics (venous invasion, poor differentiation, high tumor node metastasis grade). FOXA2 level was even lower in portal vein tumor thrombus compared with primary tumor tissues and correlated with epithelial-mesenchymal transition in HCC cells. Overexpression of FOXA2 inhibited migration and invasion of Focus cells, whereas knockdown of FOXA2 in HepG2 showed the opposite effect. Moreover, upregulation of FOXA2 suppressed HCC metastasis to bone, brain and lung in two distinct mouse models. Finally, we proved that FOXA2 repressed the transcription of matrix metalloproteinase (MMP)-9 and exerted its antimetastasis effect partially through downregulation of MMP-9. In conclusion, our findings indicate that FOXA2 plays a critical role in HCC metastasis and may serve as a novel therapeutic target for HCC.

Hepatocyte nuclear factor 4α-nuclear factor-κB feedback circuit modulates liver cancer progression.

UNLABELLED: Hepatocyte nuclear factor 4α (HNF4α) is a liver enriched transcription factor and is indispensable for liver development. However, the role of HNF4α in hepatocellular carcinoma (HCC) progression remains to be elucidated. We report that reduced HNF4α expression correlated well with the aggressive clinicopathological characteristics of HCC and predicted poor prognosis of patients. HNF4α levels were even lower in metastatic HCCs, and ectopic HNF4α expression suppressed the metastasis of hepatoma cells both in vitro and in vivo. Forced HNF4α expression attenuated the expression and nuclear translocation of RelA (p65) and impaired NF-κB activation through an IKK-independent mechanism. Blockage of RelA robustly attenuated the suppressive effect of HNF4α on hepatoma cell metastasis. MicroRNA (miR)-7 and miR-124 were transcriptionally up-regulated by HNF4α, which repressed RelA expression by way of interaction with RelA-3' untranslated region (UTR). In addition, nuclear factor kappa B (NF-κB) up-regulated the expression of miR-21 in hepatoma cells, resulting in decreased HNF4α levels through down-regulating HNF4α-3'UTR activity. CONCLUSIONS: Collectively, an HNF4α-NF-κB feedback circuit including miR-124, miR-7, and miR-21 was identified in HCC, and the combination of HNF4α and NF-κB exhibited more powerful predictive efficiency of patient prognosis. These findings broaden the knowledge of hepatic inflammation and cancer initiation/progression, and also provide novel prognostic biomarkers and therapeutic targets for HCC.

Perturbation of MicroRNA-370/Lin-28 homolog A/nuclear factor kappa B regulatory circuit contributes to the development of hepatocellular carcinoma.

UNLABELLED: MicroRNA 370 (miR-370) is located within the DLK1/DIO3 imprinting region on human chromosome 14, which has been identified as a cancer-associated genomic region. However, the role of miR-370 in malignances remains controversial. Here, we report that miR-370 was repressed in human hepatocellular carcinoma (HCC) tissues and hepatoma cell lines. Using gain-of-function and loss-of-function experiments, we demonstrated that miR-370 inhibited the malignant phenotype of HCC cells in vitro. Overexpression of miR-370 inhibited growth and metastasis of HCC cells in vivo. Moreover, the RNA-binding protein, LIN28A, was identified as a direct functional target of miR-370, which, in turn, blocked the biogenesis of miR-370 by binding to its precursor. LIN28A also mediated the suppressive effects of miR-370 on migration and invasion of HCC cells by post-transcriptionally regulating RelA/p65, which is an important effector of the canonical nuclear factor kappa B (NF-κB) pathway. Interleukin-6 (IL-6), a well-known NF-κB downstream inflammatory molecule, reduced miR-370 but increased LIN28A levels in HCC. Furthermore, miR-370 levels were inversely correlated with LIN28A and IL-6 messenger RNA (mRNA) levels, whereas LIN28A mRNA expression was positively correlated with IL-6 expression in human HCC samples. Interestingly, reduction of miR-370 expression was associated with the development of HCC in rats, as well as with aggressive tumor behavior and short survival in HCC patients. CONCLUSIONS: These data demonstrate the involvement of a novel regulatory circuit consisting of miR-370, LIN28A, RelA/p65 and IL-6 in HCC progression. Manipulating this feedback loop may have beneficial effect in HCC treatment.