HER2, MET and FGFR2 oncogenic driver alterations define distinct molecular segments for targeted therapies in gastric carcinoma

Background:

Gastric cancer (GC) is a leading cause of cancer deaths worldwide. Since the approval of trastuzumab, targeted therapies are emerging as promising treatment options for the disease. This study aimed to explore the molecular segmentation of several known therapeutics targets, human epidermal growth factor receptor 2 (HER2), MET and fibroblast growth factor receptor 2 (FGFR2), within GC using clinically approved or investigational kits and scoring criteria. Knowledge of how these markers are segmented in the same cohort of GC patients could improve future clinical trial designs.

Methods:

Using immunohistochemistry (IHC) and FISH methods, overexpression and amplification of HER2, FGFR2 and MET were profiled in a cohort of Chinese GC samples. The correlations between anti-tumour sensitivity and the molecular segments of HER2, MET and FGFR2 alterations were further tested in a panel of GC cell lines and the patient-derived GC xenograft (PDGCX) model using the targeted inhibitors.

Results:

Of 172 GC patients, positivity for HER2, MET and FGFR2 alternations was found in 23 (13.4%), 21 (12.2%) and 9 (5.2%) patients, respectively. Positivity for MET was found in 3 of 23 HER2-positive GC patients. Co-positivity for FGFR2 and MET was found in 1 GC patient, and amplification of the two genes was found in different tumour cells. Our study in a panel of GC cell lines showed that in most cell lines, amplification or high expression of a particular molecular marker was mutually exclusive and in vitro sensitivity to the targeted agents lapatinib, PD173074 and crizotinib was only observed in cell lines with the corresponding high expression of the drugs' target protein. SGC031, an MET-positive PDGCX mouse model, responded to crizotinib but not to lapatinib or PD173074.

Conclusions:

Human epidermal growth factor receptor 2, MET and FGFR2 oncogenic driver alterations (gene amplification and overexpression) occur in three largely distinct molecular segments in GC. A significant proportion of HER2-negative patients may potentially benefit from MET- or FGFR2-targeted therapies.

Spontaneous neuronal activity predicts intersubject variations in executive control of attention

Executive control of attention regulates our thoughts, emotion and behavior. Individual differences in executive control are associated with task-related differences in brain activity. But it is unknown whether attentional differences depend on endogenous (resting state) brain activity and to what extent regional fluctuations and functional connectivity contribute to individual variations in executive control processing. Here, we explored the potential contribution of intrinsic brain activity to executive control by using resting-state functional magnetic resonance imaging (fMRI). Using the amplitude of low-frequency fluctuations (ALFF) as an index of spontaneous brain activity, we found that ALFF in the right precuneus (PCUN) and the medial part of left superior frontal gyrus (msFC) was significantly correlated with the efficiency of executive control processing. Crucially, the strengths of functional connectivity between the right PCUN/left msFC and distributed brain regions, including the left fusiform gyrus, right inferior frontal gyrus, left superior frontal gyrus and right precentral gyrus, were correlated with individual differences in executive performance. Together, the ALFF and functional connectivity accounted for 67% of the variability in behavioral performance. Moreover, the strength of functional connectivity between specific regions could predict more individual variability in executive control performance than regionally specific fluctuations. In conclusion, our findings suggest that spontaneous brain activity may reflect or underpin executive control of attention. It will provide new insights into the origins of inter-individual variability in human executive control processing.

Improved post-prandial ghrelin response by nateglinide or acarbose therapy contributes to glucose stability in Type 2 diabetic patients

BACKGROUND

Recent studies highlight an important role of ghrelin in glucose homeostasis, while the association between ghrelin regulation and glucose fluctuation is unclear.

AIM

We compared the effects of two postprandial hypoglycemic agents on ghrelin response and determined the contribution of ghrelin response to glucose stability in Type 2 diabetic (T2DM) patients.

SUBJECTS AND METHODS

Forty newly- diagnosed T2DM patients were randomly allocated to receive nateglinide or acarbose for 4 weeks, with twenty body mass index (BMI)-matched normoglycemic subjects as controls. Mean glucose values and daily average glucose excursion were assessed using continuous glucose monitoring system. Serum ghrelin levels were determined by enzyme-linked immunosorbent assay.

RESULTS

T2DM patients had similar fasting ghrelin levels (p=0.546), while their postprandial ghrelin suppressions at 30 min and 120 min were reduced as compared to BMI-matched normoglycemic controls (p<0.01). Both nateglinide and acarbose increased post-prandial ghrelin suppression at 120 min and reduced ghrelin area under the curve (AUCGHRL) (p<0.05), while only nateglinide increased postprandial ghrelin suppression at 30 min (p<0.01), which was positively correlated with the increased early-phase insulin secretion by 4 weeks of nateglinide therapy (r=0.48, p=0.05). The decrease in AUCGHRL was positively correlated with the decrease in daily average glucose excursion and mean glucose values either by 4 weeks of nateglinide or acarbose therapy (p<0.05).

CONCLUSIONS

Both nateglinide and acarbose increase post-prandial ghrelin suppression. Improved ghrelin regulation is most likely to play a role in glucose stability in T2DM patients with nateglinide or acarbose therapy.

Protective effect of the nitric oxide pathway in L-citrulline renal ischaemia-reperfusion injury in rats

To observe the protective effects of L-citrulline on the renal I/R injury and elucidate the mechanisms involved, 48 rats were randomized into eight groups: Group 1: sham operated; Group 2: I/R (45 min renal ischaemia and 24 h reperfusion); Group 3: I/R + L-citrulline (300 mg/kg, i.g.); Group 4: I/R + L-citrulline (600 mg/kg, i.g.); Group 5: I/R + L-citrulline (900 mg/kg, i.g.); Group 6: I/R + normal saline (NS, i.g.); Group 7: I/R + N sup ω nitro-L-arginine ester (L-NAME, 20 mg/kg, i.p.); Group 8: I/R + L-citrulline (900 mg/kg, i.g.) + L-NAME (20 mg/ kg, i.p.). At the end of the reperfusion period, serum was collected and the kidneys underwent histological and biochemical examinations. Our results showed that pre-treatment with L-citrulline (300, 600, and 900 mg/kg) significantly ameliorated the renal injury caused by I/R. Moreover, L-citrulline prevented induction of lipid peroxidation and increased the activity of superoxide dismutase and the levels of glutathione and nitric oxide. The I/R-induced decreases in total nitric oxide synthase activity, inducible nitric oxide activity, constitutive nitric oxide activity and endothelial nitric oxide protein expression in the renal cortex were significantly prevented. However, the L-citrulline-mediated protection was significantly antagonized by co-administration of L-NAME. These results suggested that L-citrulline administration exhibited significant protection against renal I/R injury. This protective effect, at least in part, via up-regulation of the endothelial nitric oxide protein expression and constitutive nitric oxide synthase activity, maintained production of nitric oxide at the basal level.

Investigation of the vitamin D receptor gene (VDR) and its interaction with protein tyrosine phosphatase, non-receptor type 2 gene (PTPN2) on risk of islet autoimmunity and type 1 diabetes: the Diabetes Autoimmunity Study in the Young (DAISY)

The present study investigated the association between variants in the vitamin D receptor gene (VDR) and protein tyrosine phosphatase, non-receptor type 2 gene (PTPN2), as well as an interaction between VDR and PTPN2 and the risk of islet autoimmunity (IA) and progression to type 1 diabetes (T1D). The Diabetes Autoimmunity Study in the Young (DAISY) has followed children at increased risk of T1D since 1993. Of the 1692 DAISY children genotyped for VDR rs1544410, VDR rs2228570, VDR rs11568820, PTPN2 rs1893217, and PTPN2 rs478582, 111 developed IA, defined as positivity for GAD, insulin or IA-2 autoantibodies on 2 or more consecutive visits, and 38 IA positive children progressed to T1D. Proportional hazards regression analyses were conducted. There was no association between IA development and any of the gene variants, nor was there evidence of a VDR*PTPN2 interaction. Progression to T1D in IA positive children was associated with the VDR rs2228570 GG genotype (HR: 0.49, 95% CI: 0.26-0.92) and there was an interaction between VDR rs1544410 and PTPN2 rs1893217 (p(interaction)=0.02). In children with the PTPN2 rs1893217 AA genotype, the VDR rs1544410 AA/AG genotype was associated with a decreased risk of T1D (HR: 0.24, 95% CI: 0.11-0.53, p=0.0004), while in children with the PTPN2 rs1893217 GG/GA genotype, the VDR rs1544410 AA/AG genotype was not associated with T1D (HR: 1.32, 95% CI: 0.43-4.06, p=0.62). These findings should be replicated in larger cohorts for confirmation. The interaction between VDR and PTPN2 polymorphisms in the risk of progression to T1D offers insight concerning the role of vitamin D in the etiology of T1D.

Bifidobacterium infantis-mediated HSV-TK/GCV suicide gene therapy induces both extrinsic and intrinsic apoptosis in a rat model of bladder cancer

Bladder cancer is the most common cancer in the urological tract. Here, we investigated the molecular pathways involved in the apoptosis of rodent bladder cancer, which was treated with Bifidobacterium infantis (BI)-mediated herpes simplex virus thymidine kinase (HSV-TK)/ganciclovir (GCV) suicide gene therapy. We engineered the BI-TK system, which consists of BI with the recombinant plasmid PGEX-1λT carrying HSV-TK (that is, TK) gene. Tumor-bearing rats were randomly divided into three groups and tail vein injected with normal saline (group A), BI/PGEX-1λT (group B) or BI-TK (group C), followed by intraperitoneal injection of GCV. The BI-TK/GCV system (group C) was shown to inhibit tumor growth and caused the apoptosis of tumor cells as assessed by in situ terminal transferase dUTP nick-end labeling assay. While varied extents of apoptosis were detected in tumor cells from all groups, tumor cells treated with BI-TK/GCV system (group C) exhibited the highest level of apoptosis (P < 0.05), consistent with our previous studies. Furthermore, we found that the expression levels of Fas, FasL, Cyt-C and caspase-9 in tumor tissues derived from group C were significantly higher than the other two groups (P < 0.001). Therefore, our results have demonstrated that the BI-TK/GCV therapy system exhibits a sustainable antitumor growth activity in the rodent model of bladder cancer. Mechanistically, both extrinsic and intrinsic apoptosis pathways are involved in the BI-TK/GCV antitumor functionality.

Global variability in diabetes mellitus and its association with body weight and primary healthcare support in 49 low- and middle-income developing countries

AIMS

In the absence of any previous global comparison, we examined the variability in prevalence of diabetes mellitus across 49 developing countries, and the associations of diabetes with body weight and primary healthcare support using data from the World Health Survey.

METHODS

Diabetes mellitus was defined by individuals' self-report of a physician diagnosis of diabetes. BMI is the weight (kg)/the square of the height (m). Healthcare support was assessed using clinical treatment status and whether patients with diabetes followed prescribed behaviour changes to control diabetes. Associations of diabetes with BMI and diabetes treatment status were analysed cross-sectionally.

RESULTS

A total of 215898 participants were included in the analysis. Age-adjusted prevalence of diabetes ranged from 0.27% (Mali) to 15.54% (Mauritius). Participants who were underweight (BMI <18.5 kg/m(2) ), overweight (BMI 25-29.9 kg/m(2) ) and obese (BMI ≥ 30 kg/m(2) ) were significantly associated with odds of having diabetes as compared with those who were of normal weight (BMI 18.5-24.9 k/m(2) ), with corresponding values of multivariate adjusted odds ratios (95% CI) of 1.15 (1.07-1.24), 1.56 (1.44-1.68) and 2.35 (2.17-2.61), respectively. The overall untreated rate of those with diabetes mellitus was 9.6% in the total sample. Patients with underweight had the highest diabetes untreated rate, followed by those with normal weight, overweight and obesity.

CONCLUSION

There are significant variations in prevalence of diabetes and primary healthcare support for diabetes across low- and middle-income countries. Aggressively preventing abnormal body weight and improving healthcare support may play a pivotal role in ameliorating the unfavourable epidemic of diabetes in developing countries.

Effect of interaction of vitamin C on macrophage immune response to infection with Mycobacterium bovis

Bovine tuberculosis is a chronic infectious disease caused by Mycobacterium bovis affecting humans and livestock. Like Mycobacterium tuberculosis (M.tb), M. bovis can persist in cattle without causing overt symptoms after entering a non-replicating persistent (NRP) state. Given that M.tb enters NRP under stress conditions, we sought to find the effects of vitamin C (VC) on M. bovis in vitro and in vivo (VC could mimic stresses like hypoxia by O2 scavenging and acidic conditions in phagosome). M. bovis was cultured in a medium with VC for 48 h. The differential expression of five genes (dosR, dosS, dosT, icl, and hspX of M. bovis) implicated in the M. bovis NRP state was measured with real-time quantitative PCR. Expression of all five genes was increased by VC. Relative to the control, VC-exposed bacteria appeared smaller and more rounded in shape with a much thicker inner envelope. A lower number of viable bacteria were found in comparison with those of the control. We infected macrophage cell line ANA-1 with M. bovis and cultured it in VC-added medium (MC group) for 24h and 48 h. Expression of il-10, il-6, tnf-α, and il-β was examined and compared with expression by cells infected by M. bovis only without VC treatment (MB group), uninfected cells in the medium treated with VC (VC group), and cells in the medium only without VC. Il-1β, tnf-α, and il-6 transcription were up-regulated significantly in MC group. IL-10 gene expression in MB and MC groups was less than in the control at 24h, but that of MC group increased more than the MB group at 48 h. The numbers of intracellular M. bovis in the MC group were lower than that in the other groups. Slower growth was found in VC-treated M. bovis, and macrophages were more bactericidal for intracellular VC-stimulated M. bovis than for M. bovis with no VC treatment.

Hypoxia induces angiogenic factors in brain microvascular endothelial cells

Hypoxia is increasingly recognized as an important contributing factor to the development of brain diseases such as Alzheimer's disease (AD). In the periphery, hypoxia is a powerful regulator of angiogenesis. However, vascular endothelial cells are remarkably heterogeneous and little is known about how brain endothelial cells respond to hypoxic challenge. The objective of this study is to characterize the effect of hypoxic challenge on the angiogenic response of cultured brain-derived microvascular endothelial cells. Brain endothelial cell cultures were initiated from isolated rat brain microvessels and subjected to hypoxia (1% O(2)) for various time periods. The results showed that hypoxia induced rapid (≤ 0.5h) expression of hypoxia-inducible factor 1α (HIF-1α) and that cell viability, assessed by MTT assay, was unaffected within the first 8h. Examination of brain endothelial cell cultures for pro- and anti-angiogenic proteins by western blot, RT-PCR and ELISA revealed that within 0.5 to 2h of hypoxia levels of vascular endothelial growth factor and endothelin-1 mRNA and protein were elevated. The expression of heme oxygenase-1 also increased but only after 8h of hypoxia. In contrast, similar hypoxia exposure evoked a decrease in endothelial nitric oxide synthase and thrombospondin-2 levels. Exposure of brain endothelial cell cultures to hypoxia resulted in a significant (p<0.001) decrease (94%) in tube length, an in vitro index of angiogenesis, compared to control cultures. The data indicate that, despite a shift toward a pro-angiogenic phenotype, hypoxia inhibited vessel formation in brain endothelial cells. These results suggest that in brain endothelial cells expression of angiogenic factors is not sufficient for the development of new vessels. Further work is needed to determine what factors/conditions prevent hypoxia-induced angiogenic changes from culminating in the formation of new brain blood vessels and what role this may play in the pathologic changes observed in AD and other diseases characterized by cerebral hypoxia.

Expression of PTEN and survivin in cervical cancer: promising biological markers for early diagnosis and prognostic evaluation

This study aims to evaluate the expression of the antioncogene phosphatase and tensin (PTEN) homologue and survivin, a protein encoded by the anti-apoptotic gene baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5), in the progression of cervical neoplasia and to elucidate the relationship between PTEN and survivin expression based on clinicopathological features in squamous cell carcinoma of the uterine cervix. A total of 20 patients with cervical ectropion and squamous metaplasia, 30 with cervical intraepithelial neoplasia, and 49 with cervical squamous cell carcinoma were enrolled in the study. Immunohistochemical staining was performed to detect PTEN and survivin expression in each group. Normal cervical epithelium from 10 people served as the control. Results showed that PTEN expression progressively decreased with the continuum from normal epithelium to squamous cell carcinoma (P < 0.05), whereas survivin expression progressively increased (P < 0.05). Furthermore, positive PTEN immunostaining was associated with clinical stage and tumour size (P < 0.05). The level of PTEN expression in the metastatic pelvic lymph node group was significantly lower compared with the non-metastatic pelvic lymph node group (P < 0.01). Positive PTEN immunostaining was not associated with age or degree of differentiation (P > 0.05). Positive survivin immunostaining was associated with clinical stage and tumour size (P < 0.05). Survivin-positive expression in the metastatic pelvic lymph node group was significantly higher compared with the nonmetastatic pelvic lymph node group (P < 0.01). No obvious relationship was found between survivin expression and patient age (P > 0.05). PTEN expression negatively correlated with survivin expression in cervical intraepithelial neoplasia and cervical squamous cell carcinoma (P < 0.01). PTEN and survivin expression correlated with incidence and progression of uterine cervical cancer. Positive expression levels of PTEN and survivin provide potential evaluation indices for early diagnosis and prognosis of uterine cervical cancer, and these biomarkers are also potentially promising therapeutic targets.

Leaf photosynthesis and respiration of three bioenergy crops in relation to temperature and leaf nitrogen: how conserved are biochemical model parameters among crop species?

Given the need for parallel increases in food and energy production from crops in the context of global change, crop simulation models and data sets to feed these models with photosynthesis and respiration parameters are increasingly important. This study provides information on photosynthesis and respiration for three energy crops (sunflower, kenaf, and cynara), reviews relevant information for five other crops (wheat, barley, cotton, tobacco, and grape), and assesses how conserved photosynthesis parameters are among crops. Using large data sets and optimization techniques, the C(3) leaf photosynthesis model of Farquhar, von Caemmerer, and Berry (FvCB) and an empirical night respiration model for tested energy crops accounting for effects of temperature and leaf nitrogen were parameterized. Instead of the common approach of using information on net photosynthesis response to CO(2) at the stomatal cavity (A(n)-C(i)), the model was parameterized by analysing the photosynthesis response to incident light intensity (A(n)-I(inc)). Convincing evidence is provided that the maximum Rubisco carboxylation rate or the maximum electron transport rate was very similar whether derived from A(n)-C(i) or from A(n)-I(inc) data sets. Parameters characterizing Rubisco limitation, electron transport limitation, the degree to which light inhibits leaf respiration, night respiration, and the minimum leaf nitrogen required for photosynthesis were then determined. Model predictions were validated against independent sets. Only a few FvCB parameters were conserved among crop species, thus species-specific FvCB model parameters are needed for crop modelling. Therefore, information from readily available but underexplored A(n)-I(inc) data should be re-analysed, thereby expanding the potential of combining classical photosynthetic data and the biochemical model.

No association of vitamin D intake or 25-hydroxyvitamin D levels in childhood with risk of islet autoimmunity and type 1 diabetes: the Diabetes Autoimmunity Study in the Young (DAISY)

AIMS/HYPOTHESIS

The aim of the study was to investigate the association between vitamin D intake and status and the risk of islet autoimmunity (IA) and subsequent type 1 diabetes in children at increased risk of type 1 diabetes.

METHODS

The Diabetes Autoimmunity Study in the Young (DAISY) in Denver, CO, USA, has been following children at increased risk of diabetes since 1993. As of February 2011, 198 children developed IA during follow-up of 2,644 DAISY children. Vitamin D intake and plasma 25-hydroxyvitamin D [25(OH)D] were measured longitudinally. Proportional hazards regression analyses of time to IA, or type 1 diabetes in IA-positive children, were conducted, with vitamin D intake and 25(OH)D as time-varying covariates. HRs were calculated for a standard deviation difference in exposure, with adjustment for confounders.

RESULTS

Intake of vitamin D was not associated with the risk of IA (adjusted HR 1.13; 95% CI 0.95, 1.35; p = 0.18) nor progression to diabetes in IA-positive children (adjusted HR 1.30; 95% CI 0.91, 1.86; p = 0.15). Moreover, 25(OH)D level was not associated with the risk of IA (adjusted HR 1.12; 95% CI 0.88, 1.43; p = 0.36), nor progression to diabetes in IA-positive children (adjusted HR 0.91; 95% CI 0.68, 1.22; p = 0.54). In the 128 children in whom we measured 25(OH)D at 9 months of age, 25(OH)D was not associated with risk of IA (n = 30 IA-positive children) (adjusted HR 1.02; 95% CI 0.96, 1.07; p = 0.58).

CONCLUSIONS/INTERPRETATION

Neither vitamin D intake nor 25(OH)D levels throughout childhood were associated with the risk of IA or progression to type 1 diabetes in our population.

Production of a novel bioflocculant MNXY1 by Klebsiella pneumoniae strain NY1 and application in precipitation of cyanobacteria and municipal wastewater treatment

AIMS

To isolate and characterize the novel bioflocculant-producing bacteria, to optimize the bioflocculant production and to evaluate its potential applications.

METHODS AND RESULTS

Klebsiella pneumoniae strain NY1, a bacterium that produces a novel bioflocculant (MNXY1), was selected on the chemically defined media. It was classified according to the 16S rRNA gene sequence, morphological and microscopic characteristics. MNXY1 was characterized to contain 26% protein and 66% total sugar. The constituent sugar monomers of MNXY1, revealed by NMR analysis, are glucose, galactose and quinovose. Favourable culture conditions for MNXY1 production were determined. Strain NY1 produces a high level (14.9 g l(-1)) of MNXY1. MNXY1 is thermostable and tolerant to the extreme pH. It precipitated 54% of cyanobacteria from laboratory culture and 72% of the total suspended solids from raw wastewater.

CONCLUSIONS

Strain NY1 was identified to produce a novel bioflocculant MNXY1. The outstanding performance of MNXY1 in practical applications and its availability in copious amounts make it attractive for further investigation and development for industrial scale applications.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is first report for the identification of a quinovose-containing bioflocculant and application of a protein-polysaccharide complex bioflocculant in precipitation of cyanobacteria. These findings suggest that MNXY1 holds great potential for use in management of harmful algae and city wastewater treatment.

Somatic cell cryopreservation and protoplast regeneration of important disease-resistant wild riceOryza meyeriana Baill

Oryza meyeriana Baill is one of the three wild rice species found in Chiia.O. mcyeriana possesses valuable characteristics but is reluctant in cell culturein vitro. In a series of experiments, callus with no regeneration ability was induced from young panicle ofO. meyeriana. The callus was subcultured and propagated. Embryogenic cell clones were obtained after cryopreswation. Suspension cultures were established and protoplasts were isolated and regenerated into plants. Results of artificial inoculation ofXanthomonas campestris pv.Oryzae showed that the strong resistance did not change in the regenerated plants. The development of protoplast-to-plant system is an important progress towards utilization ofO. meyeriana via cellular engineering. The experiments demonstrated that cryopreservation of plant calli was a new way to obtain embryogenic cell line.

Dcdc2 knockout mice display exacerbated developmental disruptions following knockdown of doublecortin

The dyslexia-associated gene DCDC2 is a member of the DCX family of genes known to play roles in neurogenesis, neuronal migration, and differentiation. Here we report the first phenotypic analysis of a Dcdc2 knockout mouse. Comparisons between Dcdc2 knockout mice and wild-type (wt) littermates revealed no significant differences in neuronal migration, neocortical lamination, neuronal cilliogenesis or dendritic differentiation. Considering previous studies showing genetic interactions and potential functional redundancy among members of the DCX family, we tested whether decreasing Dcx expression by RNAi would differentially impair neurodevelopment in Dcdc2 knockouts and wild-type mice. Consistent with this hypothesis, we found that deficits in neuronal migration, and dendritic growth caused by RNAi of Dcx were more severe in Dcdc2 knockouts than in wild-type mice with the same transfection. These results indicate that Dcdc2 is not required for neurogenesis, neuronal migration or differentiation in mice, but may have partial functional redundancy with Dcx.

Efficacy of oxaliplatin plus 5-fluorouracil/leucovorin (FOLFOX4) versus doxorubicin in advanced HCC: Updates on the EACH study

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Background: In Asia, where hepatitis B is very common, patients often present with locally advanced or metastatic hepatocellular carcinoma (HCC), and their prognosis is poor. The EACH study was designed to evaluate the efficacy and safety of FOLFOX4 vs. doxorubicin as palliative systemic chemotherapy in advanced HCC.

Methods: The open-label, randomized, multicenter phase III study was conducted in 371 patients in China, Taiwan, Korea and Thailand, who had locally advanced or metastatic HCC and were ineligible for resection. Patients were randomized 1:1 to receive either FOLFOX4 (oxaliplatin 85 mg/m2 i.v. d1; LV 200 mg/m2 i.v. h0–h2 d1 and d2; 5FU 400 mg/m2 i.v. bolus h2, then 600 mg/m2 over 22 hours d1 and d2 q2w) or doxorubicin (50 mg/m2 i.v. q3w). The primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS), response rate (RR) by RECIST and safety. Data from final and follow-up analyses of the intent-to-treat (ITT) population and selected subgroup analyses are presented.

Results: At the final analysis, median OS with FOLFOX4 (N = 184) was 6.40 months (95% CI: 5.30, 7.03) vs. 4.97 months (95% CI: 4.23, 6.03) with doxorubicin [N = 187; p = 0.0695 using a stratified log-rank test; statistical significance (p = 0.0425) was achieved at the post hoc follow-up analysis conducted 7 months later]. Median PFS with FOLFOX4 was 2.93 months (95% CI: 2.43, 3.53) vs. 1.77 months with doxorubicin (95% CI: 1.63, 2.30; p = 0.0002). The RR was 8.2% vs. 2.7% of patients with FOLFOX4 and doxorubicin, respectively (p = 0.0233), and the disease control rate (DCR) was 52.2% vs. 31.6% (p < 0.0001). In the Chinese sub-population, OS, PFS, RR and DCR were significantly improved with FOLFOX4 vs. doxorubicin at both the final and follow-up analyses. In the other subgroups analyzed, the OS and PFS benefits of FOLFOX4 vs. doxorubicin were generally consistent.

Conclusions: In the ITT population, median OS was greater with FOLFOX4 than doxorubicin throughout the study and statistical significance was achieved after continued follow-up. FOLFOX4 can benefit patients with advanced HCC, as it significantly increases median OS, PFS, RR and DCR compared with doxorubicin.

[Table: see text]

The clinical values of methylation status of P16 and APC genes in bile in diagnosis of malignant obstructive jaundice

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Background: Preoperative definitive diagnosis of malignant obstructive jaundice caused by biliary and pancreatic carcinomas still remains a major challenge. Hypermethylation of tumor suppressor genes have been implied in carcinogenesis of biliary and pancreatic malignancies. The diagnostic values of methylation status of tumor suppressor genes in bile in malignant obstructive jaundice have not been well-documented.

Methods: Bile was prospectively collected from 70 patients with obstructive jaundice treated at our hospital between November 2008 and Sepetember 2009. Forty-eight of them were proved to be malignant obstructive jaundice (biliary carcinoma in 36, pancreatic carcinoma in 8 and duodenal carcinoma in 4) by pathological examination, and 22 were benign obstructive jaundice caused by cholelithiasis. DNA was extracted from bile and modified by sodium bisulfite. Methylation-specific PCR was run to detect methylation status of P16 and APC gene promoters. Their diagnostic values in malignant obstructive jaundice were assessed.

Results: Hypermethylation of P16 promoter was presented in 72.9% (35/48) malignant obstructive jaundice, and 9% (2/22) bengin obstructive jaundice (p<0.05). Hypermethylation of APC promoter was presented in 56.2% (27/48) malignant obstructive jaundice, and 9% (2/22) bengin obstructive jaundice (p<0.05). With respect to their diagnostic values in malignant obstructive jaundice, sensitivity, specificity, positive predictivity and negative predictivity were 72.9%, 90.9%, 94.6% and 60.6%, respectively, for P16 gene; 56.2%, 90.9%, 93.1%, 48.8%, respectively, for APC gene.

Conclusions: Methylation status of P16 and APC gene promoters in bile was valuable in diagnosis of malignant obstructive jaundice, with an excellent specificity. P16 gene had a higher sensitivity than APC gene.

No significant financial relationships to disclose.

Simulation of wheat growth and development based on organ-level photosynthesis and assimilate allocation

Intimate relationships exist between form and function of plants, determining many processes governing their growth and development. However, in most crop simulation models that have been created to simulate plant growth and, for example, predict biomass production, plant structure has been neglected. In this study, a detailed simulation model of growth and development of spring wheat (Triticum aestivum) is presented, which integrates degree of tillering and canopy architecture with organ-level light interception, photosynthesis, and dry-matter partitioning. An existing spatially explicit 3D architectural model of wheat development was extended with routines for organ-level microclimate, photosynthesis, assimilate distribution within the plant structure according to organ demands, and organ growth and development. Outgrowth of tiller buds was made dependent on the ratio between assimilate supply and demand of the plants. Organ-level photosynthesis, biomass production, and bud outgrowth were simulated satisfactorily. However, to improve crop simulation results more efforts are needed mechanistically to model other major plant physiological processes such as nitrogen uptake and distribution, tiller death, and leaf senescence. Nevertheless, the work presented here is a significant step forwards towards a mechanistic functional-structural plant model, which integrates plant architecture with key plant processes.

Complete genome sequence of a tobacco isolate of the tobacco vein banding mosaic virus strain prevailing in China

Tobacco vein banding mosaic virus (TVBMV) is a species of the largest plant virus genus Potyvirus. Its incidence has been increasing in Chinese tobacco-growing area. TVBMV isolates can be clustered into three genetic groups that are corresponding with their geographical origin. We have reported the complete genomic sequence of TVBMV isolate YND with unique NIb/CP cleavage site. Here, we determined and analyzed the complete genomic sequence of isolate HN39, which was collected from tobacco in Henan Province and represented Chinese prevalent strain of TVBMV. HN39 has similar host range with YND, but induce mild vein banding symptom in Nicotiana tabacum cv. Samsun. The genome of TVBMV-HN39 is composed of 9,570 nucleotides, excluding the poly(A) tail. It contains a large ORF of 9,240 nucleotides and encode a polyprotein of 3,079 amino acids. The putative NIa-Pro cleavage site for NIb/CP is Q/G. The identities between the complete genomes of isolates HN39 and YND were 90.0% at nucleotide level and 95.4% at amino acid level. As for other potyviruses, HN39 shared the highest identity with wild tomato mosaic virus (WTMV) at complete genomic level, while different genes shared the highest identities with different potyviruses. This is the second complete genomic sequence of TVBMV reported.

Height growth velocity, islet autoimmunity and type 1 diabetes development: the Diabetes Autoimmunity Study in the Young

AIMS/HYPOTHESIS

Larger childhood body size and rapid growth have been associated with increased type 1 diabetes risk. We analysed height, weight, BMI and velocities of growth in height, weight and BMI, for association with development of islet autoimmunity (IA) and type 1 diabetes.

METHODS

Since 1993, the Diabetes Autoimmunity Study in the Young (DAISY) has followed children at increased type 1 diabetes risk, based on HLA-DR, -DQ genotype or family history, for the development of IA and type 1 diabetes. IA was defined as the presence of autoantibodies to insulin, GAD or protein tyrosine phosphatase islet antigen 2 twice in succession, or autoantibody-positive on one visit and diabetic at the next consecutive visit within 1 year. Type 1 diabetes was diagnosed by a physician. Height and weight were collected starting at age 2 years. Of 1,714 DAISY children <11.5 years of age, 143 developed IA and 21 progressed to type 1 diabetes. We conducted Cox proportional hazards analysis to explore growth velocities and size measures for association with IA and type 1 diabetes development.

RESULTS

Greater height growth velocity was associated with IA development (HR 1.63, 95% CI 1.31-2.05) and type 1 diabetes development (HR 3.34, 95% CI 1.73-6.42) for a 1 SD difference in velocity.

CONCLUSIONS/INTERPRETATION

Our study suggests that greater height growth velocity may be involved in the progression from genetic susceptibility to autoimmunity and then to type 1 diabetes in pre-pubertal children.

The effects of a soluble activin type IIB receptor on obesity and insulin sensitivity

Myostatin, also known as Growth and Differentiation Factor 8, is a secreted protein that inhibits muscle growth. Disruption of myostatin signaling increases muscle mass and decreases glucose, but it is unclear whether these changes are related. We treated mice on chow and high-fat diets with a soluble activin receptor type IIB (ActRIIB.Fc) which is a putative endogenous signaling receptor for myostatin and other ligands of the TGF-β superfamily. After 4 weeks, RAP-031 increased lean and muscle mass, grip strength, and contractile force. RAP-031 enhanced the ability of insulin to suppress glucose production under clamp conditions in high-fat fed mice, but did not significantly change insulin-mediated glucose disposal. The hepatic insulin sensitizing effect of RAP-031 treatment was associated with increased adiponectin levels. RAP-031 treatment for 10 weeks further increased muscle mass and drastically reduced fat content in mice on either chow or high-fat diet. RAP-031 suppressed hepatic glucose production and increased peripheral glucose uptake in chow fed mice. In contrast, RAP-031 suppressed glucose production with no apparent change in glucose disposal in high-fat diet mice. Our findings demonstrate that disruption of ActRIIB signaling is a viable pharmacological approach for treating obesity and diabetes.