High glucose attenuates insulin-induced VEGF expression in bovine retinal microvascular endothelial cells

PURPOSE

To investigate the effect of high glucose on insulin-induced vascular endothelial growth factor (VEGF) expression in bovine retinal microvascular endothelial cells (BRECs) and to probe into related mechanisms.

METHODS

BRECs were isolated as primary cultures and identified by immunostaining. Passage cells were initially exposed to normal (5 mM) or high glucose (30 mM) for 3 days, and equimolar L-glucose was supplemented for osmotic equation. BRECs were then treated with 100 nM insulin for 24 h or not, and cells were prepared for the determination of VEGF mRNA expression by real-time PCR. VEGF protein was determined by human umbilical vein endothelial cell proliferation assay, immunofluorescence, and ELISA. BRECs were treated with 5 or 30 mM glucose for 3 days and then cells cultured with 5 mM glucose were exposed to the PI3-K inhibitor wortmannin (100 nM), the P42/44 mitogen-activated protein kinase (MAPK) inhibitor U0126 (50 microM), or to the protein kinase C (PKC) inhibitor GF109203X (2 microM) 1 h before addition of 100 nM insulin. Twenty-four hours after incubation with insulin, the cells were subjected to real-time PCR and ELISA analyses.

RESULTS

Insulin or high glucose alone markedly increased VEGF mRNA and protein levels in BRECs (P<0.05, two-way ANOVA). However, the combination of insulin and high glucose displayed a weaker effect in promoting VEGF expression than did insulin alone (P<0.05, t-test). Pretreatment of cells with PI3-K inhibitor significantly (P<0.05, one-way ANOVA) suppressed the insulin-induced VEGF expression; neither pretreatment with the PKC inhibitor nor with the P42/p44 MAPK inhibitor showed an effect on the expression of VEGF at the mRNA or protein level (P>0.05, one-way ANOVA).

CONCLUSIONS

Both insulin and high glucose can markedly increase VEGF expression in BRECs at the mRNA and protein level. We propose that insulin may upregulate VEGF expression through the PI3-K signalling pathway in BRECs, and high glucose may attenuate insulin-induced VEGF expression by impairing PI3-K signalling pathways.

Tryptophan aspartate-containing coat protein (CORO1A) suppresses Toll-like receptor signalling in Mycobacterium leprae infection

Mycobacterium leprae is an intracellular pathogen that survives within the phagosome of host macrophages. Several host factors are involved in producing tolerance, while others are responsible for killing the mycobacterium. Tryptophan aspartate-containing coat protein (TACO; also known as CORO1A or coronin-1) inhibits the phagosome maturation that allows intracellular parasitization. In addition, the Toll-like receptor (TLR) activates the innate immune response. Both CORO1A and TLR-2 co-localize on the phagosomal membrane in the dermal lesions of patients with lepromatous leprosy. Therefore, we hypothesized that CORO1A and TLR-2 might interact functionally. This hypothesis was tested by investigating the effect of CORO1A in TLR-2-mediated signalling and, inversely, the effect of TLR-2-mediated signalling on CORO1A expression. We found that CORO1A suppresses TLR-mediated signal activation in human macrophages, and that TLR2-mediated activation of the innate immune response resulted in suppression of CORO1A expression. However, M. leprae infection inhibited the TLR-2-mediated CORO1A suppression and nuclear factor-kappaB activation. These results suggest that the balance between TLR-2-mediated signalling and CORO1A expression will be key in determining the fate of M. leprae following infection.

New mutations in the transglutaminase 1 gene in three families with lamellar ichthyosis

BACKGROUND

Autosomal recessive lamellar ichthyosis (LI) is a severe skin disorder characterized by generalized hyperkeratosis. Gene mutation in transglutaminase 1 (TGM1), which mediates cross-links in the formation of the cell envelope during terminal differentiation of epidermis, has been identified as a cause of LI.

OBJECTIVES

To determine mutations of TGM1 gene in three Chinese families with LI.

METHODS

The TGM1 gene was sequenced to identify disease-causing mutations in the three families with LI. One of the results was confirmed by using reverse transcriptase PCR and in situ hybridization. An in situ transglutaminase (TGase) 1 assay was performed to estimate TGase 1 activity in the patients' skin.

RESULTS

Four novel mutations of keratinocyte TGase1 (Q203X, D254N, R687H and IVS4 + 1G-->T) were found in the three families. No TGase 1 mRNA was detected in patient skin using RT-PCR and in situ hybridization, and the in situ TGase assay showed that there was no or decreased TGase 1 activity in patient skin.

CONCLUSIONS

Our findings suggest that four novel mutations in TGM1 gene result in decrease or absence of TGase activity in the skin and, as a consequence, cause the phenotype of LI.

Sudden onset fatigue (SOF) in patients with breast cancer: Characteristics and symptomatology

e20637

Background: Cancer-related fatigue is underrecognized and poorly managed. Unpredictability and rapid onset in fatigue is stressed by cancer patients but seldom addressed by health care professionals. Although sudden onset of cancer-related fatigue is anecdotally documented across qualitative studies, the symptom has never been systematically investigated. Our purpose is to describe the symptom and clinical characteristics of SOF in breast cancer patients receiving chemotherapy. Methods: This is a cross-sectional descriptive study enrolling female breast cancer outpatients undergoing chemotherapy in an urban cancer center. A brief questionnaire assessing the symptom characteristics of SOF was completed by subjects. Comprehensive metabolic panel and complete blood counts, were obtained. Descriptive statistics described the symptom characteristics of SOF. Mann-Whitney tests examined the differences between those who did and did not experience SOF. Results: Thirty patients have been enrolled. Median age 53 years (31 to 65; SD=7.7), 60% were Black. 80% (n=24) experienced SOF in the past 7 days with a median of 4 days a week and 2.5 episodes per day. SOF was most likely (75%) to occur in the afternoon while patients were engaging in activities. Levels of fatigue before, during, and after a specific episode of SOF were 5, 9, and 5, respectively, on 0–10 (highest) rating scale. Weakness, sweating, or pain sometimes accompanied SOF. When SOF occurred, individuals immediately needed to stop activities to rest until it went away. Those who experienced SOF had significantly lower levels of calcium (Median=8.9 vs. 9.4), albumin (Median=3.7 vs. 7.1), and hematocrit (Median=32.1 vs. 36) (p<0.05). Those who experienced SOF also had higher levels of GPT (Median=25.5 vs. 17), lower levels of total protein (Median=6.7 vs. 7.1), WBC (Median=4.9 vs. 8.9), RBC (Median=3.4 vs. 3.9), and hemoglobin (Median=10.7 vs. 11.4). Conclusions: Our ongoing study is one of the first to identify the characteristics of patients at high risk of SOF. SOF needs to be recognized and managed when patients undergo chemotherapy. Associated conditions should be identified and addressed. The ultimate goal is to minimize the distress and improve the quality of life of patients receiving chemotherapy.

No significant financial relationships to disclose.

Population pharmacokinetics of pegylated liposomal CKD-602 (S-CKD602) in patients with advanced solid tumors

2545

Background: CKD-602, a semi-synthetic analogue of campothecin, is a potent topoisomerase I inhibitor. S-CKD602, a PEGylated long-circulating liposomal formulation of CKD-602, was developed to achieve a longer intra-tumoral exposure of CKD602 and a higher therapeutic index. Age and body composition were reported to affect the pharmacokinetics (PK) of S- CKD602 (Zamboni, ASCO'07). A population PK model for encapsulated and released CKD-602 following administration of S- CKD602 was developed to assess factors that may influence S-CKD602 PK. Methods: Plasma samples from 45 patients (pts) with solid tumors were collected in a phase I study. S-CKD602 was administered as a 1 h IV infusion with doses ranging from 0.1 to 2.5 mg/m2. Plasma concentrations of encapsulated (n=292) and released (n=268) CKD-602 were measured by LC-MS/MS, and population PK modeling was performed using NONMEM. Results: Pts were classified as linear and nonlinear pts according to the clearance (CL) of encapsulated CKD-602 using a classic two stage PK modeling approach. Mean ± SD ratio of total body weight to ideal body weight of pts with linear and nonlinear CL of encapsulated CKD-602 was 1.13 ± 0.16 and 1.53 ± 0.29, respectively (P = 0.003). PK of encapsulated CKD-602 was described by 1-compartment model with nonlinear CL (Michaelis-Menten kinetics). PK of released CKD-602 was described by a 2- compartment model with linear CL for all pts. The presence of primary or metastatic tumor(s) located in the liver decreased the inter- individual variability (IIV) in the CL of encapsulated CKD-602 by 13%. Typical values of Vmax of encapsulated CKD-602 in pts with and without hepatic tumor(s) were 156 and 103 μg/h, respectively (P < 0.001). The inclusion of age decreased IIV in the release of CKD-602 from S-CKD602 by 22%. Typical values of release of CKD-602 from S-CKD602 in pts < 60 years old (yo) and pts ≥ 60 yo were 0.21 and 0.10 L/h, respectively (P < 0.001). Conclusions: These data suggest that older patients (pts ≥ 60 yo) have a reduced release of CKD-602 from S-CKD602. In addition, pts with tumors in the liver may have an increased clearance of S-CKD602. These observations have potential implications in the optimal dosing of liposomal agents.

[Table: see text]

Association of GCKR rs780094, alone or in combination with GCK rs1799884, with type 2 diabetes and related traits in a Han Chinese population

AIMS/HYPOTHESIS

The GCKR rs780094 and GCK rs1799884 polymorphisms have been reported to be associated with dyslipidaemia and type 2 diabetes in white Europeans. The aim of this study was to replicate these associations in Han Chinese individuals and to identify the potential mechanisms underlying these associations.

METHODS

The single nucleotide polymorphisms rs780094 and rs1799884 were genotyped in a population-based sample of Han Chinese individuals (n = 3,210) and tested for association with risk of type 2 diabetes and related phenotypes.

RESULTS

The GCKR rs780094 A allele was marginally associated with reduced risk of type 2 diabetes (OR 0.85, 95% CI 0.73-1.00, p value under an additive model [p((add))] = 0.05) and significantly associated with reduced risk of impaired fasting glucose (IFG) or type 2 diabetes (OR 0.86, 95% CI 0.77-0.96, p([add]) = 0.0032). It was also significantly associated with decreased fasting glucose and increased HOMA of beta cell function (HOMA-B) and fasting triacylglycerol levels (p([add]) = 0.0169-5.3 x 10(-6)), but not with HOMA of insulin sensitivity (HOMA-S). The associations with type 2 diabetes and IFG remained significant after adjustment for BMI, while adjustment for HOMA-B abolished the associations. The GCKR rs780094 was also associated with obesity and BMI, independently of its association with type 2 diabetes. The GCK rs1799884 A allele was significantly associated with decreased HOMA-B (p([add]) = 0.0005), but not with type 2 diabetes or IFG. Individuals with increasing numbers of risk alleles for both variants had significantly lower HOMA-B (p([add]) = 5.8 x 10(-5)) in the combined analysis.

CONCLUSIONS/INTERPRETATION

Consistent with observations in white Europeans, the GCKR rs780094 polymorphism contributes to the risk of type 2 diabetes and dyslipidaemia in Han Chinese individuals. In addition, we showed that the effect on type 2 diabetes is probably mediated through impaired beta cell function rather than through obesity.

[Studies on immunoprotection in mice after immunization with Schistosoma japonicum 22.6 kDa recombinant protein]

AIM

To evaluate the immunoprotective effect of Schistosoma japonicum recombinant 22.6 kDa (rSj22.6) and Sj22.6/Sj26 GST fusion protein.

METHODS

The Sj22.6/Sj26 GST fusion protein was prepared by affinity chromatography using glutathione Sepharose 4B. The purified rSj22.6 could be cleaved easily from the fusion protein with Thrombin. 17 and 12 mice immunized with rSj22.6 and Sj22.6/Sj26 GST separately were each challenged with 40 +/- 1 S. japonicum cercariae.

RESULTS

In BALB/c mice, the rSj22.6 and Sj22.6/Sj26 GST could induce 32.1 (P < 0.005) and 34.9% (P < 0.02) worm reduction, respectively, as well as 28.4% (P < 0.02) and 45.1% (P < 0.005) total egg reduction, respectively.

CONCLUSION

Bpth rSj22.6 and Sj22.6/Sj26 GST fusion protein are partially effective against S. japonicum.

Genetic variation in ORM1-like 3 (ORMDL3) and gasdermin-like (GSDML) and childhood asthma

BACKGROUND

A genome-wide association study identified ORM1-like 3 (orosomucoid 1-like 3, ORMDL3) as an asthma candidate gene. Single nucleotide polymorphisms (SNPs) in the region including ORMDL3 on chromosome 17q21 were related to childhood asthma risk and ORMDL3 expression levels in Europeans.

OBJECTIVE

We examined whether polymorphisms in ORMDL3 and the adjacent gasdermin-like (GSDML) gene associated with asthma in the genome-wide association study are related to childhood asthma and atopy in a Mexico City population.

METHODS

We genotyped rs4378650 in ORMDL3 and rs7216389 in GSDML in 615 nuclear families consisting of asthmatic children aged 4-17 years and their parents. Atopy was determined by skin prick tests to 25 aeroallergens.

RESULTS

Individuals carrying the C allele of rs4378650 or the T allele of rs7216389 had increased risk of asthma [relative risk (RR) = 1.73, 95% confidence interval (CI) 1.19-2.53, P = 0.003 for one or two copies of rs4378650 C, and RR = 1.64, 95% CI 1.12-2.38, P = 0.009 for one or two copies of rs7216389 T). Linkage disequilibrium between the two SNPs was high (r(2) = 0.92). Neither of the SNPs was associated with the degree of atopy. A meta-analysis of five published studies on rs7216389 in nine populations gave an odds ratio for asthma of 1.44 (95% CI, 1.35-1.54, P < 0.00001).

CONCLUSIONS

Our results and the meta-analysis provide evidence to confirm the finding from a recent genome-wide association study that polymorphisms in ORMDL3 and the adjacent GSDML may contribute to childhood asthma.

EDA gene mutations underlie non-syndromic oligodontia

Recent studies have detected mutations in the EDA gene, previously identified as causing X-linked hypohidrotic ectodermal dysplasia (XLHED), in two families with X-linked non-syndromic hypodontia. Notably, all affected males in both families exhibited isolated oligodontia, while almost all female carriers showed a milder or normal phenotype. We hypothesized that the EDA gene could be responsible for sporadic non-syndromic oligodontia in affected males. In this study, we examined 15 unrelated males with non-syndromic oligodontia. Three novel EDA mutations (p.Ala259Glu, p. Arg289Cys, and p.Arg334His) were identified in four individuals (27%). A genetic defect in the EDA gene could result in non-syndromic oligodontia in affected males.

Preliminary experience with indications for liver transplantation for hepatolithiasis

OBJECTIVE

The aim of this study was to explore the indications for liver transplantation among patients with hepatolithiasis.

PATIENTS AND METHODS

Data from 1,431 consecutive patients who underwent surgical treatment from January 2000 to December 2006 were retrospectively collected for analysis. Surgical procedures included T-tube insertion combined with intraoperative cholangioscopic removal of intrahepatic stones, hepatectomy, cholangiojejunostomy, and liver transplantation.

RESULTS

Nine hundred sixty-one patients who had a stone located in the left or right intrahepatic duct underwent hepatectomy or T-tube insertion combined with intraoperative cholangioscopic removal of intrahepatic stones. The rate of residual stones was 7.5%. Four hundred seventy patients who had a stone located in the bilateral intrahepatic ducts underwent surgical procedures other than liver transplantation; the rate of residual stones was 21.7%. Only 15 patients with hepatolithiasis underwent liver transplantation; they all survived. According to the degree of biliary cirrhosis, recipients were divided into 2 groups: a group with biliary decompensated cirrhosis (n = 7), or group with compensated cirrhosis or no cirrhosis (n = 8). There were significant differences in operative times, transfusion volumes, and blood losses between the 2 groups (P < .05). In the first group, 6 of 7 patients experienced surgical complications, and in the second, 8 recipients recovered smoothly with no complications. Health status, disability, and psychological wellness of all recipients (n = 15) were significantly improved at 1 year after transplantation compared with pretransplantation (P < .05).

CONCLUSIONS

Liver transplantation is a possible method to address hepatolithiasis and secondary decompensated biliary cirrhosis or difficult to remove, diffusely distributed intrahepatic duct stones unavailable by hepatectomy, cholangiojejunostomy, and choledochoscopy.

Loss of PTEN engages ErbB3 and IGF-I receptor signaling to promote antiestrogen resistance in breast cancer

Abstract #73

We sought to determine whether loss of the lipid phosphatase PTEN confers resistance to antiestrogens in estrogen receptor (ER)-positive breast cancer cells and primary tumors. Stable knockdown of PTEN expression (PTEN-kd) with shRNA in MCF-7, T47D, and MDA-361 ER+ human breast cancer cells resulted in upregulation of PI3K and P-Akt, resistance to tamoxifen and faslodex, and estrogen-independent growth. Upon PTEN-kd, ER levels were maintained in MCF-7 cells but markedly reduced in T47D and MDA-361 cells. While PTEN-kd upregulated ER transcriptional reporter activity in MCF-7 cells, opposite effects were seen in T47D and MDA-361 cells.&#x2028; We evaluated mechanisms of PI3K activation in PTEN-kd cells by immunoprecipitating the p85 regulatory subunit of PI3K and examining p85-bound tyrosine-phosphorylated adaptors or receptors. PTEN-kd increased the binding of p85 to IRS-1 (MCF-7) and ErbB3 (T47D). PTEN-kd increased PI3K pathway sensitivity to IGF-I (MCF-7) and endogenous ligand (T47D, MDA-361). PTEN-kd cells had increased and prolonged activation of IGF-IR and ErbB3, thus implicating PTEN in the regulation of signaling upstream of PI3K. Further, PTEN-kd increased non-genomic, estrogen-induced signaling via IGF-IR by increasing p85-IRS-1 binding and activation of PI3K/Akt in MCF-7 cells. Inhibition of PI3K and mTOR with the small molecule BEZ235, of IGF-IR with the small molecule AEW541, and/or of ErbB2-mediated activation of ErbB3 with lapatinib restored the growth inhibitory effect of antiestrogens.&#x2028; We generated gene expression signatures of PTEN loss in each cell line by microarray analyses. Comparison of these signatures to the Connectivity Map (Science 313:1929, 2006) suggested activation of PI3K, as signatures of PTEN loss negatively connected with those induced by the PI3K inhibitors wortmannin and LY294002 (all p&lt;0.06). We found a 24-gene signature of PTEN loss common to all 3 lines, which we used to score the gene expression profiles of tumors from a cohort of 268 patients with ER+ breast cancer treated with adjuvant tamoxifen for 5 yrs and a median follow-up of 9.1 years (BMC Genomics 9:239, 2008). Patients with tumors exhibiting a signature of PTEN loss had shorter relapse-free survival (p&lt;0.0001; log rank test). Eleven genes in the PTEN signature were individually predictive of disease outcome (p&lt;0.05). In a separate, smaller cohort of patients with ER+ cancers treated with adjuvant tamoxifen (n=34), undetectable PTEN in tumor cells (measured by IHC) correlated with shorter relapse-free survival vs. tumors with detectable PTEN (p=0.06). These data suggest that 1) PTEN loss confers antiestrogen resistance to ER+ breast cancer by genomic and non-genomic mechanisms; 2) PTEN loss is permissive for activation of IGF-IR and ErbB3 signaling; 3) inhibition of IGF-IR and/or ErbB signaling pathways overcomes the resistance to antiestrogens conferred by PTEN loss; and 4) a gene expression signature reflective of loss of PTEN and/or absence of PTEN protein can predict poor patient outcome after adjuvant hormonal therapy.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 73.

Morphological variety of the soft palate in normal individuals: a digital cephalometric study

OBJECTIVES

The literature describes the morphology of the soft palate as being of only one kind and ignores its diversity, but in our clinical work we discovered that the morphology of the soft palate has a variable presentation on lateral cephalometry. The aim of our study was to investigate the variation of the velar morphology.

METHODS

In this study, the sample comprised 200 normal subjects whose ages ranged from 5-48 years (mean 19.37 years). The morphology of the soft palate on lateral cephalometry was examined and classified into six types. The dimensional differences of the soft palate between each pair of types and the differences in proportion to different age and gender groups were also studied.

RESULTS

The morphology of the soft palate was classified into six types. There was a significant difference between the pre-adult and adult groups and also between male and female groups in proportion to velar type. The velar length in Type 3 was significantly shorter than in all other types apart from Type 6. However, there was no significant difference between any two of the other 5 types.

CONCLUSIONS

The soft palate has variable radiographic appearances on lateral cephalometry. The classification system and statistical findings here may help the research of velopharyngeal closure in cleft palate individuals, and aetiological study of obstructive sleep apnoea syndrome and other conditions.

Efficient lipid production with Trichosporon fermentans and its use for biodiesel preparation

Effects of medium components and culture conditions on biomass and lipid production of Trichosporon fermentans were studied. The optimal nitrogen source, carbon source and C/N molar ratio were peptone, glucose and 163, respectively. The favorable initial pH of the medium and temperature were 6.5 and 25 degrees C. Under the optimized conditions, a biomass of 28.1 g/l and a lipid content of 62.4% could be achieved after culture for 7 days, which were much higher than the original values (19.4 g/l and 50.8%) and the results reported by other groups. T. fermentans could grow well in pretreated waste molasses and a lipid yield of 12.8 g/l could be achieved with waste molasses of 15% total sugar concentration (w/v) at pH 6.0, representing the best result with oleaginous microorganisms on agro-industrial residues. Addition of various sugars to the pretreated molasses could efficiently enhance the accumulation of lipid and the lipid content reached as high as above 50%. Similar to vegetable oils, the lipid mainly contains palmitic acid, stearic acid, oleic acid and linoleic acid and the unsaturated fatty acids amount to about 64% of the total fatty acids. The microbial oil with an acid value of 5.6 mg KOH/g was transesterified to biodiesel by base catalysis after removal of free fatty acids and a high methyl ester yield of 92% was obtained.

Improvement of biodiesel production by lipozyme TL IM-catalyzed methanolysis using response surface methodology and acyl migration enhancer

The process of biodiesel production from corn oil catalyzed by lipozyme TL IM, an inexpensive 1,3-position specific lipase from Thermomyces lanuginosus was optimized by response surface methodology (RSM) and a central composite rotatable design (CCRD) was used to study the effects of enzyme dosage, ratio of t-butanol to oil (v/v) and ratio of methanol to oil (mol/mol) on the methyl esters (ME) yield of the methanolysis. The optimum combinations for the reaction were 25.9U/goil of enzyme, 0.58 volume ratio of t-butanol to oil and 0.5, 0.5, 2.8 molar equivalent of methanol to oil added at the reaction time of 0, 2, and 4h, respectively, by which a ME yield of 85.6%, which was very close to the predicted value of 85.0%, could be obtained after reaction for 12h. Waste oil was found to be more suitable feedstock, and could give 93.7% ME yield under the optimum conditions described above. Adding triethylamine (TEA), an acyl migration enhancer, could efficiently improve the ME yield of the methanolysis of corn oil, giving a ME yield of 92.0%.