Activating mechanism of transcriptor NF-kappaB regulated by hepatitis B virus X protein in hepatocellular carcinoma

AIM:To investigate the mechanism and significance of NF-κB activation regulated by hepatitis B virus X protein (HBx) in hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC).METHODS:The expression levels of HBx, p65,IκB-α and ubiquitin were detected by immunohistochemistry in HCC tissue microarrays (TMA) respectively, and IκB-α was detected by Western blot in HCC and corresponding liver tissues.RESULTS: The percentage of informative TMA samples was 98.8% in 186 cases with a total of 367 samples. Compared with corresponding liver tissues (60.0%),the HBx expression was obviously decreased in HBV-associated HCC (47.9%,u=2.24,P<0.05).On the contrary, the expressions of p65 (20.6% vs45.3%, u=4.85, P<0.01) and ubiquitin (8.9% vs 59.0%,u=9.68,P<0.01) were notably elevated in HCC.In addition, IκB-α had a tendency to go up. Importantly, positive relativity was observed between HBx and p65 (X^2=10.26,P<0.01), p65 and IκB-α (x^2=16.86,P<0.01), IκB-α and ubiquitin (x^2=8.90, P<0.01) in HCC, respectively.CONCLUSION:Both active and non-active forms of NF-κB are increased in HBV-associated HCC. Variant HBx is the major cause of the enhancement of NF-κB activity. The activation always proceeds in nucleus and the proteasome complexes play an important role in the activation.

Microvessel density of malignant and benign hepatic lesions and MRI evaluation

AIM. To study the difference of microvessel density (MVD) between malignant and benign hepatic lesions and study the relationship between MVD and dynamic enhanced magnetic resonance imaging (MRI) for evaluation of microvessels within malignant and benign hepatic lesions. METHODS: A total of 265 specimens of hepatocellular carcinoma (HCC), 122 cirrhosis tissues and 22 hepatic benign lesions were enrolled for MVD by immunohistochemistry on tissue microarray, of which 49 underwent MRI examination before surgery, then contrast-to-noise ratios (CNR) and enhancement index (EI) in all the phases were calculated. Pearson correlation was performed for correlation analysis between CNR, EI and MVD. RESULTS: MVD of HCC was 22.7±15.8 (mean±SD), which was obviously higher than that of cirrhosis tissue (8.3±7.6, P<0.01), but was not statistically different from that of benign lesions (31.3±22.7, P>0.05). Among HCC, MVD of gradesⅠ-Ⅱ was 29.9±18.6, which was much higher than those ofgrade Ⅲ (22.2±18.2, P<0.01) and gradeⅣ (22.9±19.0, P<0.01). MVD of HCC (P=0.018) and of benign lesions (P=0.014) were both correlative with CNR in arterial phase. CONCLUSION: Neoangiogenesis is an important feature for malignant tumor, and MVD may act as a biological marker in differentiating malignant from benign hepatic lesions. Dynamic enhanced MRI, especially image in arterial phase, may act as an MVD evaluation criterion for malignant and benign hepatic lesions.

Effect of body mass index on adenocarcinoma of gastric cardia

AIM: Obesity has been proved as one of the main risk factors for gastric cardia adenocarcinoma (GCA) in the West.The objective of our research was to evaluate the relationship between obesity and the risk of GCA in people from North China.METHODS: A total of 300 patients who had been diagnosed as GCA and had accepted surgical operation at Beijing Cancer Hospital from 1995 to 2002 were enrolled. Data were collected from pathology materials and hospital records. Two hundred and fifty-eight healthy people who had accepted health examination at the same hospital during the same period were enrolled as controls. Height, weight and gender of them at the time of examination were also collected.Obesity was estimated by body mass index (BMI), computed as weight in kilograms per square surface area (Kg/m2).The degree of obesity was determined by using BMI≤ 18.5,24-27.9 and ≥28 (Kg/m2) as the cut-off points for underweight/normal, overweight and obesity, respectively.Associations with obesity were estimated by odds ratios (ORs) and 95 % confidence intervals (CIs). All ORs were adjusted for age and sex.RESULTS: The mean level of BMI was significantly lower in the patient group than that in the control group. The ORs for obesity in age groups 30-59 and 60-79 were 1.15 (95 %CI=0.37-3.65) and 0.16 (95 % CI=0.05-0.44) for males and 0.78 (95 % CI=0.26-2.36) and 0.28 (95 % CI=0.04-2.05)for females, respectively. The ORs for underweight were 2.42 (95 % CI=0.56-10.53) and 4.68 (95 % CI=1.13-19.40)for males in age subgroups 30-59 and 60-79 and 40.7 (95 %CI=9.32-177.92) for females older than 60 yrs. BMI was significantly associated with GCA (P＜0.01). Underweight people were at high risk for GCA.CONCLUSION: BMI is an independent risk factor for GCA.Underweight is positively associated with GCA.

Establishment of a P-glycoprotein substrate screening model and its preliminary application

AIM: To establish a high P-glycoprotein (P-gp) expressing cell line as a model for studying drug absorption and distribution, and to explore the preliminary application of this screening model.METHODS: A full-length MDR1 cDNA fragment in plasmid pMDRA1 was first subcloned into plasmid pET28a(+), then MDR1 cDNA was cut from the recombinant plasmid with double-digestion and ligated into the mammalian expression vector pcDNA3.1(+). The recombinant plasmid pcDNA3.1(+)/MDR1 was transfected into breast cancer cell line Bcap37 using the Superfect transfection reagent. Several stably transfected clones were obtained after selection with G418.Real-time fluorescent quantitative RT- PCR and Western blot methods were used to detect the expression of P-gp, and the cellular location of the expressed protein was determined by immunohistochemical staining. Drug sensitivity assay was used to evaluate the biological function of expressed P-gp.Concentration of quercetin in cells was determined by high-performance liquid chromatography (HPLC).RESULTS: The recombinant plasmid was confirmed to be inserted in the correct orientation by restrictive enzyme digestion and DNA sequencing. Real-time fluorescent quantitative RT-PCR showed a higher level of P-gp mRNA in transfected cells compared to that in the control cells, and the Western blot result also indicated that P-gp expression in transfected cells was higher than that in control cells. The immunohistochemical staining showed that the expressed P-gp was localized on cell membranes. Drug sensitivity assay showed that the ICs0 for adriamycin and colchicine of the transfected cells was higher than that of the control cells.The concentration of quercetin in model cells was lower than that in control cells by HPLC. After P-gp inhibitor verapamil was administered, the concentration of quercetin in model cells was increased.CONCLUSION: A high P-gp expressing cell line can be established, which could provide a suitable in vitro model system for studying drug intestinal absorption mechanism,predicting the drug permeability characteristics and screening new multi-drug resistance reversing agents. With this model,quercetin can be found to be transported by P-gp, and it is a P-gp substrate.

A key‘foxy’aroma gene is regulated by homologyinduced promoter indels in the iconic juice grape‘Concord’

‘Concord’,the most well-known juice grape with a parentage of the North American grape species Vitis labrusca L.,possesses a special‘foxy’aroma predominantly resulted from the accumulation of methyl anthranilate(MA)in berries.This aroma,however,is often perceived as an undesirable attribute by wine consumers and rarely noticeable in the common table and wine grape species V.vinifera.Here we discovered homology-induced promoter indels as a major genetic mechanism for species-specific regulation of a key‘foxy’aroma gene,anthraniloyl-CoA:methanol acyltransferase(AMAT),that is responsible for MA biosynthesis.We found the absence of a 426-bp and/or a 42-bp sequence in AMAT promoters highly associated with high levels of AMAT expression and MA accumulation in‘Concord’and other V.labrusca-derived grapes.These promoter variants,all with direct and inverted repeats,were further confirmed in more than 1,300 Vitis germplasm.Moreover,functional impact of these indels was validated in transgenic Arabidopsis.Superimposed on the promoter regulation,large structural changes including exonic insertion of a retrotransposon were present at the AMAT locus in some V.vinifera grapes.Elucidation of the AMAT genetic regulation advances our understanding of the‘foxy’aroma trait and makes it genetically trackable and amenable in grapevine breeding.

Clinical efficacy of oral enteral nutrition in lung cancer patients receiving chemotherapy and/or radiotherapy： a systematic review of randomized controlled trials

Background and Objectives： the effects of oral enteral nutrition （EN） in lung cancer patients receivingchemotherapy and/or radiotherapy were controversial, so we made a systematic review to analyze the clinicalefficacy of EN in lung cancer patients after chemotherapy and/or radiotherapy. Methods and Study Design：Pertinent studies were identified by searching in PubMed, Embase, Web of Science, Cochrane Library, ChinaNational Knowledge Infrastructure （CNKI）, WanFang Database, China Biomedical Literature database （CBM） andChinese Science and Technology Periodical Database （VIP）. Energy intake, protein intake, weight and other datawere extracted. Results： Finally, 5 randomized controlled trials （RCTs） were included in this systematic review.Patients in 3 studies received chemotherapy, in 1 with radiotherapy and in 1 with chemo-radiotherapy. Thecombined results showed that EN significantly increased energy and protein intake in lung cancer duringchemotherapy, while there was no significant effect on other results after patients had received chemotherapyand/or radiotherapy. Conclusions： Limited evidence is available to judge whether EN can improve clinical effect oflung cancer with or without chemotherapy and/or radiotherapy, as clinical heterogeneity and other potentialvariation existed in this review. Further studies are needed.

Genome-scale metabolic models applied for human health and biopharmaceutical engineering

Over the last 15 years,genome-scale metabolic models(GEMs)have been reconstructed for human and model animals,such as mouse and rat,to systematically understand metabolism,simulate multicellular or multi-tissue interplay,understand human diseases,and guide cell factory design for biopharmaceutical protein production.Here,we describe how metabolic networks can be represented using stoichiometric matrices and well-defined constraints for flux simulation.Then,we review the history of GEM development for quantitative understanding of Homo sapiens and other relevant animals,together with their applications.We describe how model develops from H.sapiens to other animals and from generic purpose to precise context-specific simulation.The progress of GEMs for animals greatly expand our systematic understanding of metabolism in human and related animals.We discuss the difficulties and present perspectives on the GEM development and the quest to integrate more biological processes and omics data for future research and translation.We truly hope that this review can inspire new models developed for other mammalian organisms and generate new algorithms for integrating big data to conduct more in-depth analysis to further make progress on human health and biopharmaceutical engineering.