Miao Shen

Salinomycin Inhibits Proliferation and Induces Apoptosis of Human Hepatocellular Carcinoma Cells In Vitro and In Vivo

The anti-tumor antibiotic salinomycin (Sal) was recently identified as a selective inhibitor of breast cancer stem cells; however, the effect of Sal on hepatocellular carcinoma (HCC) is not clear. This study aimed to determine the anti-tumor efficacy and mechanism of Sal on HCC. HCC cell lines (HepG2, SMMC-7721, and BEL-7402) were treated with Sal. Cell doubling time was determinated by drawing growth curve, cell viability was evaluated using the Cell Counting Kit 8. The fraction of CD133+ cell subpopulations was assessed by flow cytometry. We found that Sal inhibits proliferation and decreases PCNA levels as well as the proportion of HCC CD133+cell subpopulations in HCC cells. Cell cycle was analyzed using flow cytometry and showed that Sal caused cell cycle arrest of the various HCC cell lines in different phases. Cell apoptosis was evaluated using flow cytometry and Hoechst 33342 staining. Sal induced apoptosis as characterized by an increase in the Bax/Bcl-2 ratio. Several signaling pathways were selected for further mechanistic analyses using real time-PCR and Western blot assays. Compared to control, β-catenin expression is significantly down-regulated upon Sal addition. The Ca2+ concentration in HCC cells was examined by flow cytometry and higher Ca2+ concentrations were observed in Sal treatment groups. The anti-tumor effect of Sal was further verified in vivo using the hepatoma orthotopic tumor model and the data obtained showed that the size of liver tumors in Sal-treated groups decreased compared to controls. Immunohistochemistry and TUNEL staining also demonstrated that Sal inhibits proliferation and induces apoptosis in vivo. Finally, the role of Sal on in vivo Wnt/β-catenin signaling was evaluated by Western blot and immunohistochemistry. This study demonstrates Sal inhibits proliferation and induces apoptosis of HCC cells in vitro and in vivo and one potential mechanism is inhibition of Wnt/β-catenin signaling via increased intracellular Ca2+ levels.

Genistein inhibits hepatocellular carcinoma cell migration by reversing the epithelial–mesenchymal transition: Partial mediation by the transcription factor NFAT1

To investigate the effects and mechanism of genistein on hepatocellular carcinoma. Cell counting kit‐8 assays showed that genistein at 3, 6, and 9 µM had no significant cytotoxic effects on HepG2, SMMC‐7721, and Bel‐7402 cells. Cell scratch and Transwell assays identified that genistein inhibited migration of three cell lines. In three cell lines, genistein enhanced E‐cadherin and α‐catenin, but reduced N‐cadherin and Vimentin at both mRNA and protein levels in a dose‐dependent manner. Simultaneously, treatment with genistein suppressed epithelial–mesenchymal transition (EMT) induced by TGF‐β. In HepG2 cells, genistein reduced mRNA, and protein expressions of nuclear factor of activated T cells 1 (NFAT1), Abca3, Autotaxin, CD154, and Cox‐2. Phorbol 12‐myristate 13‐acetate (PMA) and ionomycin enhanced activity of NFAT1, reduced E‐cadherin and α‐catenin protein levels, and increased protein levels of N‐cadherin and Vimentin. Transwell demonstrated that PMA and ionomycin reversed the migration inhibitory effects of genistein on HepG2 cells. In vivo, genistein inhibited the intrahepatic metastasis by reversing the EMT, which was correlated with reduced NFAT1. Genistein inhibited hepatocellular carcinoma cell migration by reversing the EMT, which was partly mediated by NFAT1. The fact that EMT can be reversed by genistein may shed light on the possible mechanisms for its role in liver cancer therapy.

Protective Effects of Necrostatin-1 against Concanavalin A-Induced Acute Hepatic Injury in Mice

Objective. Necrostatin-1 (Nec-1) inhibits receptor-interacting protein 1 (RIP1) kinase and programmed necrosis. This study was designed to examine the protective effects and mechanisms of Nec-1 in concanavalin A- (ConA-) induced hepatitis in mice. Methods. C57BL/6 mice were exposed to ConA via tail vein injection and injected intraperitoneally with Nec-1 or vehicle. Levels of serum liver enzymes and histopathology were determined. Levels of inflammatory cytokines with ConA-induced hepatitis were determined with real-time polymerase chain reaction (real-time PCR). The expression of TNF-α, RIP1, and LC3 was detected with immunohistochemical staining. The expression of TNF-α, IFN-γ, IL2, IL6, caspase 3, RIP1, beclin-1, and LC3 protein was assessed by immunofluorescence and western blotting. Autophagosomes were observed with transmission electron microscopy (TEM). Results. Amelioration in liver functions and histopathological changes and the suppression of inflammatory cytokine production were observed in Nec-1-injected mice. Western blotting analysis showed that the expression of TNF-α, IFN-γ, IL2, IL6, and RIP1 was significantly reduced in the Nec-1-injected mice, which was confirmed by immunofluorescence and immunohistochemistry. Autophagosome formation was significantly reduced by Nec-1 treatment, as the expression of beclin-1 and LC3, determined with immunofluorescence and western blotting. Conclusion. These results demonstrate that Nec-1 prevents ConA-induced liver injury via RIP1-related and autophagy-related pathways.

Ethyl Pyruvate Ameliorates Hepatic Ischemia-Reperfusion Injury by Inhibiting Intrinsic Pathway of Apoptosis and Autophagy

Background. Hepatic ischemia-reperfusion (I/R) injury is a pivotal clinical problem occurring in many clinical conditions such as transplantation, trauma, and hepatic failure after hemorrhagic shock. Apoptosis and autophagy have been shown to contribute to cell death in hepatic I/R injury. Ethyl pyruvate, a stable and simple lipophilic ester, has been shown to have anti-inflammatory properties. In this study, the purpose is to explore both the effect of ethyl pyruvate on hepatic I/R injury and regulation of intrinsic pathway of apoptosis and autophagy. Methods. Three doses of ethyl pyruvate (20 mg/kg, 40 mg/kg, and 80 mg/kg) were administered 1 h before a model of segmental (70%) hepatic warm ischemia was established in Balb/c mice. All serum and liver tissues were obtained at three different time points (4 h, 8 h, and 16 h). Results. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and pathological features were significantly ameliorated by ethyl pyruvate (80 mg/kg). The expression of Bcl-2, Bax, Beclin-1, and LC3, which play an important role in the regulation of intrinsic pathway of apoptosis and autophagy, was also obviously decreased by ethyl pyruvate (80 mg/kg). Furthermore, ethyl pyruvate inhibited the HMGB1/TLR4/ NF-κb axis and the release of cytokines (TNF-α and IL-6). Conclusion. Our results showed that ethyl pyruvate might attenuate to hepatic I/R injury by inhibiting intrinsic pathway of apoptosis and autophagy, mediated partly through downregulation of HMGB1/TLR4/ NF-κb axis and the competitive interaction with Beclin-1 of HMGB1.

Meta-analysis of the efficacy of probiotics in Helicobacter pylori eradication therapy

AIM To evaluate the role of probiotics in the standard triple Helicobacter pylori therapy. METHODS In this meta-analysis, we investigated the efficacy of probiotics in a standard triple H. pylori therapy in adults. Searches were mainly conducted in MEDLINE/PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Fourteen studies met our criteria, and the quality of these studies was assessed using the Jadad scale. We used STATA version 12.0 to extract data and to calculate the odds ratios (ORs), which are presented with the corresponding 95% confidence intervals (CIs). The data are presented as forest plots. RESULTS The pooled ORs for the eradication rates calculated by intention-to-treat analysis and per-protocol analysis in the probiotic group vs the control group were 1.67 (95%CI: 1.38-2.02) and 1.68 (95%CI: 1.35-2.08), respectively, using the fixed-effects model. The sensitivity of the Asian studies was greater than that of the Caucasian studies (Asian: OR = 1.78, 95%CI: 1.40-2.26; Caucasian: OR = 1.48, 95%CI: 1.06-2.05). The pooled OR for the incidence of total adverse effects was significantly lower in the probiotic group (OR = 0.49, 95%CI: 0.26-0.94), using the random effects model, with significant heterogeneity (I (2) = 85.7%). The incidence of diarrhea was significantly reduced in the probiotic group (OR = 0.21, 95%CI: 0.06-0.74), whereas the incidence of taste disorders, metallic taste, vomiting, nausea, and epigastric pain did not differ significantly between the probiotic group and the control group. CONCLUSION Supplementary probiotic preparations during standard triple H. pylori therapy may improve the eradication rate, particularly in Asian patients, and the incidence of total adverse effects.

Protective effect of astaxanthin on liver fibrosis through modulation of TGF-β1 expression and autophagy.

Liver fibrosis is a common pathway leading to cirrhosis and a worldwide clinical issue. Astaxanthin is a red carotenoid pigment with antioxidant, anticancer, and anti-inflammatory properties. The aim of this study was to investigate the effect of astaxanthin on liver fibrosis and its potential protective mechanisms. Liver fibrosis was induced in a mouse model using CCL4 (intraperitoneal injection, three times a week for 8 weeks), and astaxanthin was administered everyday at three doses (20, 40, and 80 mg/kg). Pathological results indicated that astaxanthin significantly improved the pathological lesions of liver fibrosis. The levels of alanine aminotransferase aspartate aminotransferase and hydroxyproline were also significantly decreased by astaxanthin. The same results were confirmed in bile duct liagtion, (BDL) model. In addition, astaxanthin inhibited hepatic stellate cells (HSCs) activation and formation of extracellular matrix (ECM) by decreasing the expression of NF-κB and TGF-β1 and maintaining the balance between MMP2 and TIMP1. In addition, astaxanthin reduced energy production in HSCs by downregulating the level of autophagy. These results were simultaneously confirmed in vivo and in vitro. In conclusion, our study showed that 80 mg/kg astaxanthin had a significant protective effect on liver fibrosis by suppressing multiple profibrogenic factors.

N-acetylcysteine attenuates ischemia-reperfusion-induced apoptosis and autophagy in mouse liver via regulation of the ROS/JNK/Bcl-2 pathway.

Background Hepatic ischemia–reperfusion injury (HIRI) remains a pivotal clinical problem after hemorrhagic shock, transplantation, and some types of toxic hepatic injury. Apoptosis and autophagy play important roles in cell death during HIRI. It is also known that N-acetylcysteine (NAC) has significant pharmacologic effects on HIRI including elimination of reactive oxygen species (ROS) and attenuation of hepatic apoptosis. However, the effects of NAC on HIRI-induced autophagy have not been reported. In this study, we evaluated the effects of NAC on autophagy and apoptosis in HIRI, and explored the possible mechanism involved. Methods A mouse model of segmental (70%) hepatic warm ischemia was adopted to determine hepatic injury. NAC (150 mg/kg), a hepatoprotection agent, was administered before surgery. We hypothesized that the mechanism of NAC may involve the ROS/JNK/Bcl-2 pathway. We evaluated the expression of JNK, P-JNK, Bcl-2, Beclin 1 and LC3 by western blotting and immunohistochemical staining. Autophagosomes were evaluated by transmission electron microscopy (TEM). Results We found that ALT, AST and pathological changes were significantly improved in the NAC group. Western blotting analysis showed that the expression levels of Beclin 1 and LC3 were significantly decreased in NAC-treated mice. In addition, JNK, p-JNK, Bax, TNF-α, NF-κB, IL2, IL6 and levels were also decreased in NAC-treated mice. Conclusion NAC can prevent HIRI-induced autophagy and apoptosis by influencing the JNK signal pathway. The mechanism is likely to involve attenuation of JNK and p-JNK via scavenged ROS, an indirect increase in Bcl-2 level, and finally an alteration in the balance of Beclin 1 and Bcl-2.

Hydrogen Sulfide Ameliorates Ischemia/Reperfusion-Induced Hepatitis by Inhibiting Apoptosis and Autophagy Pathways

Background. Hepatic ischemia/reperfusion (I/R) injury is an important clinical problem, and its consequences can seriously threaten human health. Apoptosis and autophagy have been shown to contribute to cell death in hepatic I/R injury. Hydrogen sulfide (H2S) is the third most common endogenously produced gaseous signaling molecule and is known to exert a protective effect against hepatic I/R injury. In this study, the purpose is to explore both the effect and mechanism of H2S on hepatic I/R injury. Methods. Balb/c mice were randomized into Sham, I/R, or two doses (14 μmol/kg and 28 μmol/kg) of sodium hydrosulfide (NaHS, an H2S donor) preconditioning groups. Results. NaHS significantly reduced the levels of TNF-α and IL-6 at 12 h and 24 h after injection compared with ischemia/reperfusion challenge alone. The expression of Bcl-2, Bax, Beclin-1, and LC3, which play important roles in the regulation of the apoptosis and autophagy pathways, was also clearly affected by NaHS. Furthermore, NaHS affected the p-JNK1, p-ERK1, and p-p38. Conclusion. Our results indicate that H2S attenuates hepatic I/R injury, at least in part, by regulating apoptosis through inhibiting JNK1 signaling. The autophagy agonist rapamycin potentiated this hepatoprotective effect by reversing the inhibition of autophagy by H2S.

Ethyl pyruvate inhibits proliferation and induces apoptosis of hepatocellular carcinoma via regulation of the HMGB1-RAGE and AKT pathways.

Ethyl pyruvate (EP) was recently identified as a stable lipophilic derivative of pyruvic acid with significant antineoplastic activities. The high mobility group box-B1 (HMGB1)-receptor for advanced glycation end-products (RAGE) and the protein kinase B (Akt) pathways play a crucial role in tumorigenesis and development of many malignant tumors. We tried to observe the effects of ethyl pyruvate on liver cancer growth and explored its effects in hepatocellular carcinoma model. In this study, three hepatocellular carcinoma cell lines were treated with ethyl pyruvate. An MTT colorimetric assay was used to assess the effects of EP on cell proliferation. Flow cytometry and TUNEL assays were used to analyze apoptosis. Real-time PCR, Western blotting and immunofluorescence demonstrated ethyl pyruvate reduced the HMGB1-RAGE and AKT pathways. The results of hepatoma orthotopic tumor model verified the antitumor effects of ethyl pyruvate in vivo. EP could induce apoptosis and slow the growth of liver cancer. Moreover, EP decreased the expression of HMGB1, RAGE, p-AKT and matrix metallopeptidase-9 (MMP9) and increased the Bax/Bcl-2 ratio. In conclusion, this study demonstrates that ethyl pyruvate induces apoptosis and cell-cycle arrest in G phase in hepatocellular carcinoma cells, plays a critical role in the treatment of cancer.

Mechanism of action of salinomycin on growth and migration in pancreatic cancer cell lines.

OBJECTIVES Pancreatic cancer is one of the most aggressive and lethal cancers worldwide and there are few effective treatments. Recently, salinomycin (Sal) was reported to alter proliferation and apoptosis in various tumors. This prompted us to investigate the effect of Sal on pancreatic cancer cells and to explore the possible molecular mechanism in vitro. METHODS After treatment with Sal, pancreatic cancer cell viability and apoptosis were analyzed by Hoechst 33342 staining and flow cytometry, respectively. Invasion and metastasis of pancreatic cancer cells were assayed by a Transwell migration assay. Flow cytometry was also used to assessed the fraction of CD133(+) cell subpopulations. The expression of proliferating cell nuclear antigen (PCNA), Bcl-2, E-cadherin, and Wnt/β-catenin signaling-related proteins were detected by RT-PCR and western blot. RESULTS Sal inhibited the growth and migration of pancreatic cancer cells in vitro in a dose- and time-dependent manner. We found that the proportion of CD133(+) cell subpopulations decreased after treatment with Sal in pancreatic cancer cell lines at the same time. The percentage of apoptotic cells was increased after Sal treatment. Compared with control groups, Bax and E-cadherin were significantly upregulated, and Bcl-2 and PCNA were significantly downregulated in Sal-treated cells. The expression of Wnt/β-catenin signaling-related proteins (β-catenin and p-GSK-3β) was inhibited. CONCLUSIONS These results indicate that Sal could influence the cell growth and migration in pancreatic cancer cells in vitro, which may occur by inhibition of Wnt/β-catenin signaling.