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Previous studies by our group have demonstrated that extract of clove exhibits potent anticancer effects in vitro and in vivo. In the present study, the effect of an extracted and isolated active fraction of clove (AFC) on induction of cellular apoptosis in human colorectal cancer HCT-116 cells was investigated by morphological observation, flow cytometry, and western blotting analysis. The results revealed that AFC induced apoptosis of HCT-116 cells. AFC also induced autophagy, demonstrated by increased punctuate microtubule-associated protein 1A/1B-light chain 3 (LC3) staining, and LC3-II and Beclin-1 protein expression levels. Furthermore, the autophagy inhibitors 3-MA and baflomycin A1 potentiated the pro-apoptotic activity of AFC in HCT-116 cells. AFC also inhibited the phosphorylation of the phosphoinositide 3-kinase/Akt/mechanistic target of rapamycin signaling pathway. The present study may improve the existing understanding of the anticancer mechanisms of clove and provide a scientific rationale for AFC to be further developed as a promising novel anticancer agent for the treatment of colorectal cancer.

Acquired resistance to classical chemotherapeutics such as docetaxel (DTX) remains a critical challenge in breast cancer (BCa) treatment. Epigenetic modification by microRNAs (miRNAs) has been shown to play a crucial role in cancer drug resistance. Previous study, using human drug-resistant BCa tissues, has identified miR-638 as one of the most down-regulated miRNAs, but its exact roles and underlying mechanisms during the pathogenesis of chemoresistance remain to be determined. In the current study, we found that miR-638 expression was significantly down-regulated in clinical DTX-resistant BCa tissues compared to that in DTX-sensitive BCa tissues. By using the previously established DTX-resistant MCF-7 cells (MCF-7/R), we also confirmed that chemoresistant cells displayed decreased levels of miR-638. To provide the direct functional evidence, we inhibited and overexpressed miR-638 in different cell lines. Thereby, the cells were rendered more resistant or susceptible to DTX treatment. Mechanistically, the lipid-binding protein STARD10 was identified as a miR-638 target mediating the DTX-resistance. Hence, we provide a molecular explanation for acquired resistance to DTX that is caused by the miR-638 deficiency and subsequent STARD10 upregulation. In consequence, alteration of miR-638/STARD10 cascade may represent an attractive strategy in future adjuvant therapy along with DTX chemotherapy., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Aim: To investigate whether Tg737 is regulated by microRNA-548a-5p (miR-548a-5p), and correlates with hepatocellular carcinoma (HCC) cell proliferation and apoptosis., Methods: Assays of loss of function of Tg737 were performed by the colony formation assay, CCK assay and cell cycle assay in HCC cell lines. The interaction between miR-548a-5p and its downstream target, Tg737, was evaluated by a dual-luciferase reporter assay and quantitative real-time polymerase chain reaction. Tg737 was then up-regulated in HCC cells to evaluate its effect on miR-548a-5p regulation. HepG2 cells stably overexpressing miR-548a-5p or miR-control were also subcutaneously inoculated into nude mice to evaluate the effect of miR-548a-5p up-regulation on in vivo tumor growth. As the final step, the effect of miR-548a-5p on the apoptosis induced by cisplatin was evaluated by flow cytometry., Results: Down-regulation of Tg737, which is a target gene of miR-548a-5p, accelerated HCC cell proliferation, and miR-548a-5p promoted HCC cell proliferation in vitro and in vivo. Like the down-regulation of Tg737, overexpression of miR-548a-5p in HCC cell lines promoted cell proliferation, increased colony forming ability and hampered cell apoptosis. In addition, miR-548a-5p overexpression increased HCC cell growth in vivo. MiR-548a-5p down-regulated Tg737 expression through direct contact with its 3' untranslated region (UTR), and miR-548a-5p expression was negatively correlated with Tg737 levels in HCC specimens. Restoring Tg737 (without the 3'UTR) significantly hampered miR-548a-5p induced cell proliferation, and rescued the miR-548a-5p induced cell proliferation inhibition and apoptosis induced by cisplatin., Conclusion: MiR-548a-5p negatively regulates the tumor inhibitor gene Tg737 and promotes tumorigenesis in vitro and in vivo, indicating its potential as a novel therapeutic target for HCC.

Objective: To observe the effect of resveratrol and propofol, used either alone or in combination, on hepatocyte apoptosis in rats with hepatic ischemia-reperfusion injury (HIRI)., Methods: A total of 144 male SD rats were randomized into 8 equal groups, including a sham-operated group and 7 HIRI (established using Pringle method) groups with pretreatments with normal saline, Tween80, propofol (10 or 20 mg·kg(-1)·h(-1)), or resveratrol (10 or 20 mg/kg), or both propofol and resveratrol 10 min before hepatic portal vein occlusion. At 1, 3 and 6 h after the reperfusion, 6 rats from each group were sacrificed for histopathological examination of the liver tissue, detection of hepatocyte apoptosis using TUNEL assay, and measurement of Bcl-2, Bax and caspase-3 protein expressions using immunohistochemistry., Results: Compared with normal saline and Tween80, propofol and resveratrol at different doses used alone or in combination all significantly alleviated the hepatic pathologies, lowered the apoptosis index (P<0.05), increased Bcl-2 expression (P<0.05), and reduced Bax and caspase-3 expressions in the liver tissues following HIRI (P<0.05). Compared with low doses of propofol and resveratrol used alone, their combination showed more obvious protective effects against hepatocyte apoptosis (P<0.05), but at higher doses, propofol and resveratrol either alone or in combination produced similar effects., Conclusions: Propofol and resveratrol can suppress HIRI-induced hepatocyte apoptosis by up-regulating Bcl-2 and down-regulating Bax and caspase-3 expressions, and their combined use can reduce the effective doses of the drugs.

It has been reported that exposure to infrasound causes cardiac dysfunction. Allowing for the key role of apoptosis in the pathogenesis of cardiovascular diseases, the objective of this study was to investigate the apoptotic effects of infrasound. Cardiac myocytes cultured from neonatal rats were exposed to infrasound of 5 Hz at 130 dB. The apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. Also, the expression levels of a series of apoptosis-related proteins were detected. As a result, infrasound induced apoptosis of cultured rat cardiac myocytes in a time-dependant manner. The expression of proapoptotic proteins such as Bax, caspase-3, caspase-8, caspase-9, and FAS was significantly up-regulated, with concomitant down-regulated expression of antiapoptotic proteins such as Bcl-x, and the inhibitory apoptosis proteins family proteins including XIAP, cIAP-1, and cIAP-2. The expression of poly (ADP-ribose) polymerase and β-catenin, which are the substrate proteins of caspase-3, was significantly decreased. In conclusion, infrasound is an apoptotic inducer of cardiac myocytes.

Smokeless tobacco products provide an alternative to cigarettes; however, smokeless tobacco is carcinogenic and harmful to human health. This study evaluated the toxicological effects of snus extracts and cigarette smoke total particulate matter (TPM) on human umbilical vein endothelial cells (HUVECs). Treated cells were examined for cell viability, reactive oxygen species (ROS), apoptosis, and inflammatory cytokines. Moreover, we explored the mechanism of programmed cell death induced by snus. The results showed that snus extracts significantly inhibited cell viability in a dose-dependent manner. ROS was significantly increased in treatment groups, and anti-oxidant treatment could not prevent snus extract-induced cell death. Snus extracts induced apoptosis, DNA damage, activation and cleavage of caspase-3 and caspase-8, pathway-related gene change, and interleukin (IL)-6 and IL-8 release in HUVECs. Snus extracts exposure may induce cytotoxicity, ROS generation, inflammatory cytokines release, and apoptosis or DNA damage through intrinsic and extrinsic pathways in HUVECs. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of ulinastatin (UTI) pretreatment on liver regeneration and energy metabolism after 70% hepatectomy combined wíth ischemia reperfuison injury in rats. Methods Totally 120 healthy clean grade male Sprague-Dawley rats weighting 230~280 g were selected and aligned into three groups randomly: imple partial hepatectomy (PH) group, partial hepatectomy combined with ischemia reperfuison (PHIR) group and ulinastatin (UTI) group, with forty rats in each. Rats in each group had the left and middle liver lobes resected, but the remnant lobes (right and caudate lobes) were treated differently as follows: the blood flow to the reserved lobes was not occluded in PH group, but occluded for 30 minutes in PHIR group, and then reperfused. UTI group had the same liver resection and blood flow occlussion as PHIR group except for administration of ulinastatin 50 000 U/kg by i.v. injection via caudal vein. Inferior vena cava blood and the reserved liver tissue were collected to measure serum alanine transaminase (ALT) and aspartate aminotransferase (AST), apoptois index (AI), regenerated liver weight, PCNA staining as well as ATP, ADP and AMP contents. Results Serum ALT and AST activites and AI level were lower, and the regenerated liver weight and poitive PCNA staining as well as ATP content and energy charge were significantly higher inUTI group than in PHIR group (P<0.05). Conclusion ulinastatin can promote liver regeneration after major hepatectomy combined with ischemia reperfuison injury, which is possibly related to maintaining energy metabolism. [ABSTRACT FROM AUTHOR]

Abstract: Background: It was previously reported that propofol, an intravenously administered hypnotic and anesthetic agent, protects organs from ischemia–reperfusion (I/R) injury. However, the underlying mechanisms are largely unknown. Glycogen synthase kinase 3β (GSK-3β) is known to play an important role in the oxidative stress–induced apoptosis. In this study, we investigated the role of GSK-3β and mitochondrial permeability transition pore (MPTP) in the protective effects of propofol against hepatic I/R injury. Materials and methods: The left and median hepatic artery and the portal vein branches were blocked by no-damage artery clips to create the model of partial ischemia (70%), and liver lobes were subjected to warm ischemia for 30, 60, 90 min, respectively. Reperfusion of 120 min was then initiated by the removal of clamp. The MPTP opening was assessed by measuring mitochondrial large amplitude swelling and mitochondrial membrane potential. Results: Pretreatment with propofol in conditions of hepatic I/R inhibits the apoptosis of hepatocytes as evidenced by decreased terminal deoxynucleotidyl transferase dUTP nick end labeling–positive cells. Importantly, propofol suppressed the mitochondrial GSK-3β by promoting or preserving its phosphorylation at Ser9, thus restraining the opening of MPTP and preventing the mitochondrial swell and mitochondrial membrane potential collapse. Conclusions: Propofol protects liver from I/R injury by sustaining the mitochondrial function, which is possibly involved with the modulation of MPTP and GSK-3β. [Copyright &y& Elsevier]

Abstract: Background: Remifentanil protects against ischemia/reperfusion (I/R)-induced organ injury, although its underlying mechanism remains elusive. This study was designed to examine the protective effect of remifentanil preconditioning, if any, against hepatic I/R injury in rats and the underlying mechanism involved. Materials and methods: Adult Sprague-Dawley rats were randomly divided into sham operation (S group), ischemia/reperfusion (I/R group), and remifentanil preconditioning (R group) groups. Rats in the I/R group were subjected to a partial (70%) hepatic ischemia for 45 min, followed by 1 h, 3 h, and 6 h of reperfusion. Rats in the R group received venous injection of remifentanil (2 μg/kg/min) from 30 min prior to hepatic ischemia to the end of ischemia. Hepatic morphology and apoptosis were examined. Markers of liver damage, oxidative stress, and inflammation were evaluated. Mitochondrial function was assessed using mitochondrial membrane potential and appearance of mitochondrial swelling. Results: Compared with the S group, rats in the I/R group displayed a massive degenerative death in liver tissues and significantly enhanced cell apoptosis. Remifentanil preconditioning significantly reduced I/R-induced hepatocyte apoptosis. In addition, remifentanil protected against I/R-induced mitochondrial swelling and loss of membrane potential. Remifentanil preconditioning inhibited I/R-induced increases in tumor necrosis factor α, intercellular adhesion molecule 1, and nuclear factor κB p65 levels in liver tissues. Remifentanil preconditioning also inhibited the loss in superoxide dismutase and rise in malondialdehyde levels in liver tissues going through I/R injury. Conclusions: Our data revealed that remifentanil preconditioning may turn on multiple cellular pathways in hepatocytes to protect the liver from I/R injury by alleviating hepatic apoptosis. [Copyright &y& Elsevier]

Determining the origin of liver cancer stem cells is important for treating hepatocellular carcinoma. Tg737 deficiency plays an important role in the malignant transformation of liver stem cells, but the underlying mechanism remains unclear. Here we established a chemical-induced mouse hepatoma model and found that Tg737 and hepatocyte nuclear factor 4-alpha (HNF4α) expression decreased and epithelial-mesenchymal transition (EMT)-related marker expression increased during liver cancer development. To investigate the underlying mechanism, we knocked down Tg737 in WB-F344 (WB) rat hepatic oval cells. Loss of Tg737 resulted in nuclear β-catenin accumulation and activation of the Wnt/β-catenin pathway, which further promoted EMT and the malignant phenotype. XAV939, a β-catenin inhibitor, attenuated WB cell malignant transformation due to Tg737 knockdown. To clarify the relationships of Tg737, the β-catenin pathway, and HNF4α, we inhibited Snail and overexpressed HNF4α after Tg737 knockdown in WB cells and found that Snail and HNF4α comprise a negative feedback circuit. Taken together, the results showed that Tg737 regulates a Wnt/β-catenin/Snail-HNF4α negative feedback circuit, thereby blocking EMT and the malignant transformation of liver stem cells to liver cancer stem cells. [ABSTRACT FROM AUTHOR]