BackgroundHexokinase-2(HK-2) plays dual roles in glucose metabolism and mediation of cell apoptosis, making it an attractive target for cancer therapy. Chrysin is a natural flavone found in plant extracts which are widely used as herb medicine in China. In the present study, we investigated the antitumor activity of chrysin against hepatocellular carcinoma (HCC) and the role of HK-2 played for chrysin to exert its function.MethodsThe expression of HK-2 in HCC cell line and tumor tissue was examined by western blotting and immunohistochemistry staining. The activities of chrysin against HCC cell proliferation and tumor glycolysis were investigated. Chrysin-induced apoptosis was analyzed by flow cytometry. The effect of chrysin on HK-2 expression and the underlying mechanisms by which induced HCC cell apoptosis were studied. In HK-2 exogenous overexpression cell, the changes of chrysin-induced cell apoptosis and glycolysis suppression were investigated. HCC cell xenograft model was used to confirm the antitumor activity of chrysin in vivo and the effect on HK-2 was tested in chrysin-treated tumor tissue.ResultsIn contrast with normal cell lines and tissue, HK-2 expression was substantially elevated in the majority of tested HCC cell lines and tumor tissue. Owing to the decrease of HK-2 expression, glucose uptake and lactate production in HCC cells were substantially inhibited after exposure to chrysin. After chrysin treatment, HK-2 which combined with VDAC-1 on mitochondria was significantly declined, resulting in the transfer of Bax from cytoplasm to mitochondria and induction of cell apoptosis. Chrysin-mediated cell apoptosis and glycolysis suppression were dramatically impaired in HK-2 exogenous overexpression cells. Tumor growth in HCC xenograft models was significantly restrained after chrysin treatment and significant decrease of HK-2 expression was observed in chrysin-treated tumor tissue.ConclusionThrough suppressing glycolysis and inducing apoptosis in HCC, chrysin, or its derivative has a promising potential to be a novel therapeutic for HCC management, especially for those patients with high HK-2 expression.

Capsaicin is the major pungent ingredient in red peppers which is world widely consumed. Except its potent pain relieving efficacy as reported, capsaicin also exerted its antitumor activity in several tumor models. Here, we reported that capsaicin had a profound anti-proliferative effect on human colon cancer cells via inducing cell cycle G0/G1 phase arrest and apoptosis, which was associated with an increase of p21, Bax and cleaved PARP. The underlying mechanism of capsaicin's antitumor potency was mainly attributed to the stabilization and activation of p53. Capsaicin substantially prolonged the half-life of p53 and significantly elevated the transcriptional activity of p53. Through suppressing the interaction between p53 and MDM2, MDM2-mediated p53 ubiquitination was remarkably decreased after capsaicin treatment, which resulted in the stabilization and accumulation of p53. The results of p53-shRNA experiment further demonstrated that p53 knockdown severely impaired the sensitivity of tested cells to capsaicin, G0/G1 phase arrest and the apoptosis induced by capsaicin in p53-knockdown cells was also dramatically decreased, implicating the important role of p53 played in capsaicin's antitumor activity. In summary, our data suggested that capsaicin, or a related analogue, may have a role in the management of human colon cancer.

Based on current evidence, chewing gum offers an inexpensive, well-tolerated, safe and effective method to ameliorate ileus following colorectal surgery. However, tightly controlled, randomized and considerably larger multicenter trials are warranted to further validate our findings.

Background/Aims: Hepatocellular carcinoma (HCC) represents the most common type of liver cancer. DAX1 (dosage-sensitive sex reversal adrenal hypoplasia congenital critical region on X chromosome, gene 1), an atypical member of the nuclear receptor family due to lack of classical DNA-binding domains, has been known for its fundamental roles in the development, especially in the sex determination and steroidogenesis. Previous studies also showed that DAX-1 played a critical role in endocrine and sex steroid-dependent neoplasms such as adrenocortical, pituitary, endometrial, and ovarian tumors. However, its biological roles in the development of HCC remain largely unexplored. Methods: Real-time PCR and Western blot were used to detect the expression of DAX-1 in HCC tissues and cell lines. Immunoprecipitation (IP) assay was used to show the interaction between DAX-1 and β-Catenin. Small interfering RNA (siRNA) was used to silence the expression of DAX-1. BrdU incorporation and Cell-cycle assays were used to detect the role of DAX-1 in HCC cells proliferation. Migration and invasion assays were carried out to test the metastasis ability of DAX-1 in HCC cells. Results: In the present study, we found that mRNA and protein levels of DAX-1 were down-regulated in HCC tissues and cell lines. Furthermore, overexpression of DAX-1 could inhibit while its knockdown using small interfering RNA promoted cell proliferation in several HCC cell lines. At the molecular level, we demonstrated that DAX-1 could interact with β-Catenin and attenuate its transcriptional activity. Conclusion: Therefore, our results suggest a previously unknown DAX-1/β-Catenin molecular network controlling HCC development.

Background/Aims: MafB, a member of the Maf transcription factor family, plays a key role in the regulation of pancreatic alpha and beta cell differentiation. However, its function in the control of cancer cell proliferation remains unknown. Methods: The mRNA and protein expression levels of MafB in hepatocellular carcinoma tissues and adjacent non-tumor normal specimens were determined by real-time RT-PCR and Western blot, respectively. Report assay was performed to determine whether the regulation of Cyclin D1 by MafB is at the transcriptional level. The binding of MafB to the Cyclin D1 promoter was determined by Chromatin Immunoprecipitation (ChIP) assays. To determine the potential oncogenic effects of MafB in vivo, HepG2 cells transfected with adenovirus containing empty vector or MafB were injected subcutaneously to the skin under the front legs of the nude mice. Results: In the current study, we showed that MafB was markedly up-regulated in hepatocellular carcinoma (HCC) tissues and cells. Enforced overexpression of MafB enhanced, while its deficiency inhibited HCC cell proliferation. Mechanistically, Cyclin D1, an important regulator of cell cycle progression, was identified as a direct transcriptional target of MafB. Consistently, knockdown of Cyclin D1 largely attenuated the proliferative roles of MafB in HCC cells. Importantly, MafB overexpression significantly promoted cancer cell growth in mice. Conclusions: Collectively, our results identified a novel HCC regulatory pathway involving MafB and Cyclin D1, the dysfunction of which drives proliferative character in HCC.

PHA665752 (PHA), a selective small molecule c-Met Inhibitor, potently inhibited HGF-stimulated and constitutive c-Met phosphorylation, as well as HGF and c-Met-driven phenotypes of a variety of tumor cells including hepatocellular carcinoma cells. However, these effects were impaired in c-Met-deficient cancer cells. In the present study, we investigated the potential anti-human c-Met-deficient hepatocellular carcinoma effects of Celastrol, a novel triterpene, and its combination with PHA. Human hepatocellular carcinoma cells BEL-7402 (c-Met-positive) and Huh7 (c-Met-deficient) were treated with different dose of PHA with or without equal dose of Celastrol, and cell growth, cell cycle and apoptosis were evaluated, respectively, by MTT assay, flow cytometry and Caspase3/7 activity. Nude mice bearing Huh7 xenografts were used to assess the in vivo anti-tumor activity. Our results showed that Celastrol at high concentration (>1.0 μM) induced G2/M arrest and apoptosis with the activation of Caspase3/7 in Huh7 cells whereas at low concentration (<1.0 μM) had no obvious effects. Low concentration Celastrol presented significant combined effects with PHA on Huh7 cells and Huh7 xenografts in terms of growth inhibition, migration inhibition and apoptosis induction. These results suggest that Celastrol and its combination with PHA present the therapeutic potential on c-Met-deficient hepatocellular carcinoma, and deserve further preclinical and clinical studies.

Eupafolin is a flavonoid extracted from the common sage herb which has been used in China as traditional medicine. Previous studies had reported that eupafolin had antioxidative, anti-inflammatory and antitumor effects. However, the function and the mechanism of eupafolin to exert its antitumor activity, especially its effect on tumor angiogenesis, have not been elucidated. Herein, we showed that eupafolin significantly inhibited vascular endothelial growth factor (VEGF)-induced cell proliferation, migration and tube formation of human umbilical vascular endothelial cells (HUVECs) in a dose-dependent manner. Meanwhile, the new blood microvessels induced by VEGF in the matrigel plug were also substantially suppressed by eupafolin. The results of HCC xenograft experiments demonstrated eupafolin remarkably inhibited tumor growth and tumor angiogenesis in vivo, suggesting the antitumor activity exerted by eupafolin was closely correlated with its potency on tumor angiogenesis. Mechanism investigations revealed that eupafolin significantly blocked VEGF-induced activation of VEGFR2 in HUVEC cells as well as its downstream signaling pathway. In addition to the effect on endothelial cells, through inhibiting Akt activity in tumor cells, VEGF secretion in HepG2 was dramatically decreased after eupafolin treatment. Our study was the first to report the activity of eupafolin against tumor angiogenesis as well as the underlying mechanism by which eupafolin to exert its anti-angiogenic activity.

The aim of the present study was to investigate whether acylation stimulating protein (ASP) and complement component 3 (C3) are associated with the occurrence and development of coronary heart disease (CHD). The participants of the study were divided into three groups, including the healthy control (n=42), metabolic syndrome (MS, n=56) and CHD (n=62) groups. An enzyme-linked immunosorbent assay was used to measure the ASP concentrations, while an immunoturbidimetric assay was employed to determine the C3 concentrations. In addition, coronary angiography was performed to determine the severity of coronary artery disease in the CHD group. The CHD group was divided into three subgroups, according to the final Gensini score of coronary artery stenosis for each patient (mild, ≤20 points; moderate, 21–40 points; severe, >40 points). Western blotting and quantitative reverse transcription-polymerase chain reaction (RT-PCR) were performed to analyze the protein and mRNA expression levels of C3 in the CHD subgroups and the healthy control group. The concentrations of ASP and C3 in the CHD group were found to be significantly higher compared with the control and MS groups. In addition, the levels of ASP and C3 in the mild and moderate CHD subgroups were significantly higher compared with the healthy controls or mild CHD patients. Furthermore, the protein expression levels of C3 in the moderate and severe CHD patients were found to be significantly higher compared with the healthy individuals and the mild CHD patients. The quantitative RT-PCR results revealed that the mRNA expression levels of C3 in the moderate and severe CHD patients were significantly higher compared with the healthy control group and the mild CHD patients. Furthermore, the mean levels of C3 transcripts in the severe CHD patients were found to be higher compared with the moderate CHD subgroup (P<0.05). Therefore, ASP and C3 were found to be associated with the occurrence and development of CHD; thus, may be used as novel indexes for CHD.