Circular RNA circ_GLIS2 suppresses hepatocellular carcinoma growth and metastasis.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is one of the leading causes of tumour-related death. Here, we investigated the molecular mechanism of HCC by studying the function of circ_GLIS2. METHODS: Human HCC specimens and cell lines were used. Sanger sequencing, actinomycin D and RNase R treatment were performed to validate circular RNA features of circ_GLIS2. qRT-PCR, western blotting, immunostaining, and IHC were employed to examine levels of circ_GLIS2, GLIS2 mRNA, and EMT-related markers. CCK-8, colony formation, flow cytometry, wound healing assay, and transwell assays were performed to evaluate cancer cell proliferation, apoptosis, migration, and invasion. RIP and RNA pull-down assay were used to validate EIF4A3/GLIS2 mRNA interaction. MSP was performed to measure the methylation status of GLIS2 promoter. Nude mouse xenograft model was used to examine tumour growth and metastasis in vivo. RESULTS: Circ_GLIS2 and linear GLIS2 mRNA were reduced in human HCC tissues and cells. Their low levels correlated with a poor survival rate of HCC patients. Overexpression of circ_GLIS2 and GLIS2 suppressed HCC cell proliferation, migration, and invasion but promoted cell apoptosis. GLIS2 promoter region was hypermethylated in HCC cells. EIF4A3 was directly bound with GLIS2 mRNA and promoted circ_GLIS2/GLIS2 expression. Moreover, overexpression of circ_GLIS2 restrained HCC tumour growth and metastasis in vivo. CONCLUSION: Circ_GLIS2 suppresses HCC growth and metastasis by inhibiting cell proliferation, migration, and invasion, but promoting cell apoptosis. These findings provide molecular insights into the mechanism of HCC and indicate that circ_GLIS2 could serve as a diagnosis marker or therapeutic target for HCC.

Transcriptional regulation of Glis2 in hepatic fibrosis.

The role of Gli-similar 2 (Glis2) in hepatic fibrosis (HF) is controversial. In this study, we focused on the functional and molecular mechanisms involved in the Glis2-mediated activation of hepatic stellate cells (HSCs)-a milestone event leading to HF. The expression levels of Glis2 mRNA and protein were significantly decreased in the liver tissues of patients with severe HF and in mouse fibrotic liver tissues as well as HSCs activated by TGFß1. Functional studies indicated that upregulated Glis2 significantly inhibited HSC activation and alleviated BDL-induced HF in mice. Downregulation of Glis2 was found to correlate significantly with DNA methylation of the Glis2 promoter mediated by methyltransferase 1 (DNMT1), which restricted the binding of hepatic nuclear factor 1-α (HNF1-α), a liver-specific transcription factor, to Glis2 promoters. In addition, the enrichment of DNMT1 in the Glis2 promoter region was mediated by metastasis-associated lung adenocarcinoma transcriptor-1 (MALAT1) lncRNA, leading to transcriptional silencing of Glis2 and activation of HSCs. In conclusion, our findings reveal that the upregulation of Glis2 can maintain the resting state of HSCs. The decreased expression of Glis2 under pathological conditions may lead to the occurrence and development of HF with the expression silencing of DNA methylation mediated by MALAT1 and DNMT1.

[Analysis of the prophylactic effect of nucleosides against reactivation of HBV in HBsAg-positive patients with non-hepatic tumors after chemotherapy].

OBJECTIVE: To investigate the efficacy of nucleosides as a prophylactic agent against reactivation of hepatitis B virus (HBV) in HBsAg-positive patients with non-hepatic tumors after chemotherapy. METHODS: Fifty-eight patients with non-hepatic tumors were divided into prevention group and control group. The patients of prevention group received nucleosides as a prophylactic agent before chemotherapy and were compared with the control ones about the clinical manifestation of HBV reactivation. Then, the patients of the control group were divided into three groups according to antiviral drugs, use or not and time of the use. The patients having HBV reactivation but never received nucleosides were included in the group A, the patients receiving nucleosides after having HBV reactivation were divided into the group B, and the patients receiving nucleosides before HBV reactivation were divided into the group C. The progression, prognosis and curative effect among the three groups were compared. RESULTS: The rate of HBV reactivation, incidence of severe hepatitis, mortality rate of the control group (61.1%, 27.8%, 16.7%) were significantly higher than those of the prevention group (13.6%, 0, 0), and liver dysfunction was more serious than that in the prevention group. In the control group, all the 5 patients of group A died of liver failure. Of the 13 patients in the group B, 4 cases suffered from severe hepatitis and 1 of them died of the disease. Of the 18 patients in the group C, 4 cases suffered from HBV reactivation, but the clinical manifestation was milder than that of the group B. CONCLUSION: Nucleosides can be used as a prophylactic measure to prevent HBV reactivation. If chemotherapy had begun, the use of nucleosides may reduce the risk of HBV reactivation. Even if patients had suffered from HBV reactivation, the use of nucleosides may still help the recovery of liver function and improve prognosis.

11ß­hydroxysteroid dehydrogenase­1 is associated with the activation of hepatic stellate cells in the development of hepatic fibrosis.

Hepatic fibrosis (HF) is a common complication of numerous chronic liver diseases, but predominantly results from persistent liver inflammation or injury. If left untreated, HF can progress and develop into liver cirrhosis and even hepatocellular carcinoma. However, the underlying molecular mechanisms of HF remain unknown. The present study aimed to investigate the role of 11ß­hydroxysteroid dehydrogenase­1 (11ß­HSD1) during the development of hepatic fibrosis. An experimental rat model of liver fibrosis was induced using porcine serum. 11ß­HSD1 gene expression levels and enzyme activity during hepatic fibrogenesis were assessed. 11ß­HSD1 gene knockdown using small interfering RNA and overexpression were performed in LX2­human hepatic stellate cells (HSCs). HSCs were stimulated with transforming growth factor­ß1 (TGF­ß1). Cell cycle distribution, proliferation, collagen secretion and 11ß­HSD1 gene activity in HSCs were compared before and after stimulation. As hepatic fibrosis progressed, 11ß­HSD1 gene expression and activity increased, indicating a positive correlation with typical markers of liver fibrosis. 11ß­HSD1 inhibition markedly reduced the degree of fibrosis. The cell proliferation was increased, the number of cells in the G0/G1 phase decreased and the number of cells in the S and G2/M phases increased in the pSuper transfected group compared with the N group. In addition, the overexpression of 11ß­HSD1 enhanced the TGF­ß1­induced activation of LX2­HSCs and enzyme activity of connective tissue growth factor. 11ß­HSD1 knockdown suppressed cell proliferation by blocking the G0/G1 phase of the cell cycle, which was associated with HSC stimulation and inhibition of 11ß­HSD1 enzyme activity. In conclusion, increased 11ß­HSD1 expression in the liver may be partially responsible for hepatic fibrogenesis, which is potentially associated with HSC activation and proliferation.

[Analysis of antibiotics treatment in 86 cases of liver transplant recipients].

OBJECTIVE: To analyze the characteristic of bacterial infections, and the relationship between antibiotics treatment and bacterial infections after liver transplantation, and to prevent antibiotic-resistant bacterial infections. METHODS: 86 liver transplant recipients were retrospected. Different indexes including limited daily dose, the frequency of medication, drug use index were used to evaluate the rationality of the use of antibiotics, three-dimensional test was used to explore extended-spectrum beta-lactamase and AmpC enzyme of Gram-negative bacteria. RESULTS: The major pathogens of infection after liver transplantation were Enterococcus faecalis, Enterobacter cloacae, fungi and E. coli. Pre-operative antibiotic utilization rate was 83.7%, it was mainly a single use of antibiotics; After- operative antibiotic usage was 100.0%, it was mainly joint use of two or three antibiotics; The top 3 antibiotics used were cephalosporins, the combined enzyme inhibitors and penicillin. Antibiotics with drug utilization index (DUI) more than 1.1 included ampicillin and Lalin proxy. 43.3% and 31.8% of Gram -Negative bacteria produced ESBLs and AmpC, respectively, while 21.3% Gram -Negative bacteria produced two enzymes. CONCLUSION: There is high incidence of bacterial infections after liver transplantation. The use of antibiotics is high dose, high-frequency and reasonable; High resistance of bacterial infections was prone to develop and the prevention of the high resistance of bacterial infections is very important.

A meta-analysis comparing the efficacy of entecavir and tenofovir for the treatment of chronic hepatitis B infection.

The efficacy of entecavir and tenofovir in patients with chronic hepatitis B virus (HBV) is inconsistent. To address this issue, we conducted a meta-analysis based on a current review of the literature addressing the efficacy and safety of entecavir and tenofovir. Electronic databases were searched through June 2014 for relevant clinical trials. We included 2 randomized controlled trials, 2 prospective cohort studies, and 7 case-control studies that included 1,656 patients. In the entecavir group, 842 of 992 were nucleos(t)ide-naïve chronic HBV patients, and in the tenofovir group 481 of 664 were nucleos(t)ide-naïve. The virological response to tenofovir was superior to entecavir (RR: 0.82; 95%CI: 0.72-0.93), especially in nucleos(t)ide-naïve chronic HBV patients at 48 weeks (RR: 0.78; 95%CI: 0.65-0.92). Additionally, there was no difference between entecavir and tenofovir for virological response at 24 weeks (RR: 0.87, 95%CI: 0.71-1.05). The alanine aminotransferase normalization rate, serological response, and adverse event rate were also not significantly different between entecavir and tenofovir at 24 or 48 weeks after treatment. These results suggest that tenofovir is a better choice to treat chronic HBV patients than entecavir as it is better able to suppress HBV viral load and has a similar safety profile.