2,3-Diaryl-2H-1-benzopyran derivatives interfere with classical and non-classical estrogen receptor signaling pathways, inhibit Akt activation and induce apoptosis in human endometrial cancer cells

OBJECTIVES

The present study was undertaken to explore the mechanism of anti-proliferative action of benzopyran compound D1 (2-[piperidinoethoxyphenyl]-3-phenyl-2H-benzopyran) and its hydroxy-(D2) and methoxy-(D3) derivatives in Ishikawa and human primary endometrial adenocarcinoma cells.

METHODS

Transcriptional activation assays were performed using luciferase reporter system and cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The stage of cell cycle was determined by flow-cytometry and real time analysis of cyclinE1 and cdc2 genes. The apoptotic effects were measured by AnnexinV/PI staining and TUNEL. The expression of PCNA, cyclinD1, pAkt, XIAP, cleaved caspase-9, -3, PARP, Bax and Bcl2 were determined by immunoblotting. The caspase-3 activity and mitochondrial membrane potential were measured by colorimetric assay.

RESULTS

All three compounds inhibited E(2)-induced ERE- and AP-1-mediated transactivation and proliferation in endometrial adenocarcinoma cells dose-dependently. Compound D1 caused the arrest of cells in the G(2) phase while D2 and D3 caused arrest in G(1) phase of the cell cycle. All compounds interfered with Akt activation, decreased XIAP expression leading to an increased cleavage of caspase-9, -3, PARP, increased Bax/Bcl2 ratio and caspase-3 activity.

CONCLUSION

Findings suggest that benzopyran derivatives inhibit cellular proliferation via modulating ER-dependent classical and non-classical signaling mechanisms, interfere with Akt activation and induce apoptosis via intrinsic pathway in endometrial adenocarcinoma cells.

Visual function alterations in orbital tumors and factors predicting visual outcome after surgery

PURPOSE

To study the effect of orbital tumors on visual functions and highlight the factors predictive of visual outcome after surgery.

METHODS

A prospective interventional study compared visual function parameters and fundus changes, before and after surgery, in eyes having well-defined orbital tumors with the normal fellow eye. These included visual acuity (VA), refractive error, keratometry changes, color vision, Goldmann visual field (GVF), and visual evoked response (VER).

RESULTS

In total 28 cases (age range 7-56 years), of which the majority of tumors were vascular (46%) and lacrimal (18%) in origin, had a mean VA of 0.54±0.33 in the affected eye, which improved postoperatively to 0.66±0.31 (P=0.002). The affected eye had a median refractive error of +0.00 DS (-2.00 to 5.13), which was significantly more hyperopic than the normal eye (median +0.00 DS; range -1.25 to +1.63 DS) and normalized postoperatively. Keratometry showed higher astigmatism in the involved eye (P=0.004). The fundus showed disc pallor, edema, and/or choroidal folds, of which disc edema resolved in all cases after surgery. In all, 40% of the affected eyes had a deficient color vision and this partially improved postoperatively (P=0.25). GVF had abnormalities in 10 cases, half of which normalized postoperatively (P=0.04). The VER of affected eyes had a mean amplitude of 8.91±4.59 μv and latency of 116.3±14.7 ms, with improvement after surgery (P=0.005 and 0.001, respectively).

CONCLUSION

Orbital tumors adversely affected visual functions. The presenting acuity depended on disc changes, color vision abnormalities, and prolonged VER latency. The postoperative VA depended on VA at presentation, amount of proptosis, degree of hyperopia, and clinically significant VER abnormalities.

Does the hepatocellular phase of gadobenate dimeglumine help to differentiate hepatocellular carcinoma in cirrhotic patients according to histological grade?

AIM

To assess the role of the hepatocellular phase on magnetic resonance imaging (MRI) following gadobenate in characterizing the grade of hepatocellular carcinoma (HCC) in cirrhotic patients.

MATERIALS AND METHODS

A retrospective review of the MRI database from October 2004 to February 2009, performed for this Institutional Review Board-approved and Health Insurance Portability and Accountability Act (HIPAA)-complaint study, revealed 237 cirrhotic patients with focal liver lesions. Patients who had both a hepatocellular phase after gadobenate and pathological confirmation of HCC were included. Forty-six patients with 73 HCC were analysed independently by two reviewers for signal characteristics. Absolute contrast-to-noise ratio (CNR) and enhancement ratio (ER) were calculated. Univariate analysis, stepwise logistic regression analysis, and receiver operating characteristic curves (ROC) were performed.

RESULTS

The mean age was 61.3 years (range 45 to 78 years). There were 11 females and 35 males, who had 22 well-differentiated (WD HCC), 35 moderately-differentiated (MD HCC), and 16 poorly-differentiated (PD HCC) hepatocellular carcinomas. On visual analysis of the hepatocellular phase, a hyperintense or isointense lesion had a sensitivity and specificity of 45% and 76%, respectively, for WD HCC. On quantitative analysis, the only significant predictor of the grade of HCC was the ER on the hepatocellular phase (p=0.019 and 0.001 for the two reviewers in logistic regression model). On ROC analysis, an ER of >13% was 47% sensitive and 89% specific in predicting WD HCC histology.

CONCLUSION

Although the hepatocellular phase of gadobenate may help to differentiate some cases of WD HCC from the more aggressive grades, there is overlap between the different grades on qualitative and quantitative analysis.

Constitutive expression of short hairpin RNA in vivo triggers buildup of mature hairpin molecules

RNA interference (RNAi) has become the cornerstone technology for studying gene function in mammalian cells. In addition, it is a promising therapeutic treatment for multiple human diseases. Virus-mediated constitutive expression of short hairpin RNA (shRNA) has the potential to provide a permanent source of silencing molecules to tissues, and it is being devised as a strategy for the treatment of liver conditions such as hepatitis B and hepatitis C virus infection. Unintended interaction between silencing molecules and cellular components, leading to toxic effects, has been described in vitro. Despite the enormous interest in using the RNAi technology for in vivo applications, little is known about the safety of constitutively expressing shRNA for multiple weeks. Here we report the effects of in vivo shRNA expression, using helper-dependent adenoviral vectors. We show that gene-specific knockdown is maintained for at least 6 weeks after injection of 1 × 10(11) viral particles. Nonetheless, accumulation of mature shRNA molecules was observed up to weeks 3 and 4, and then declined gradually, suggesting the buildup of mature shRNA molecules induced cell death with concomitant loss of viral DNA and shRNA expression. No evidence of well-characterized innate immunity activation (such as interferon production) or saturation of the exportin-5 pathway was observed. Overall, our data suggest constitutive expression of shRNA results in accumulation of mature shRNA molecules, inducing cellular toxicity at late time points, despite the presence of gene silencing.

Barrier Layer Morphological Stability and Adhesion to Porous Low-κ Dielectrics

Two particularly important reliability issues facing the integration of low- κ dielectric films are the fracture energy of the barrier-dielectric interface and the barrier layer integrity during processing. We have noticed that the compressive stresses in the barrier layers on low- κ dielectrics lead to spontaneous delamination and formation of telephone-cord like morphologies. These morphologies allow the measurement of fracture energy and are advantageous over artificially contrived features to yield realistic debonding parameters. The fracture energy of common barrier films, TaN and Ta, was determined using this method for varying porosity nanoporous silica and MSQ. Detailed characterization of the telephone cord morphology using a combination of Optical Microscopy, SEM and Profilometry was done. The fracture energy for Ta on different low-κ dielectrics was evaluated using a 1-D model for straight buckles. The kinetic coefficient of buckling was also evaluated.

Effect of Dielectric Pore Size Distribution on Interfacial Adhesion of the Tantalum-Porous Dielectric Interface

In this work we report the adhesion of a thin Tantalum (Ta) barrier films deposited on nanoporous dielectric substrates (Xerogel and Methyl Silesquioxanes (MSQ)). The high compressive stresses in the Ta barrier layer lead to spontaneous delamination from the underlying substrate resulting in a telephone cord like morphology, which allows the measurement of critical interfacial adhesion (fracture) energy. The fracture energy of Ta barrier films on different porous substrates is evaluated using the above two methods and the resulting differences are explained. Fracture energy varies inversely as a power law with the dielectric pore size indicating pores are essential to delamination in the barrier-dielectric interface. The observed trend of fracture energy is related to other mechanical properties of the porous substrate offering insights into the underlying mechanisms governing fracture of films deposited on porous substrates.

Expression analysis of loci associated with type 2 diabetes in human tissues

AIMS/HYPOTHESIS

Genetic mapping has identified over 20 loci contributing to genetic risk of type 2 diabetes. The next step is to identify the genes and mechanisms regulating the contributions of genetic risk to disease. The goal of this study was to evaluate the effect of age, height, weight and risk alleles on expression of candidate genes in diabetes-associated regions in three relevant human tissues.

METHODS

We measured transcript abundance for WFS1, KCNJ11, TCF2 (also known as HNF1B), PPARG, HHEX, IDE, CDKAL1, CDKN2A, CDKN2B, IGF2BP2, SLC30A8 and TCF7L2 by quantitative RT-PCR in human pancreas (n = 50), colon (n = 195) and liver (n = 50). Tissue samples were genotyped for single nucleotide polymorphisms (SNPs) associated with type 2 diabetes. The effects of age, height, weight, tissue and SNP on RNA expression were tested by linear modelling.

RESULTS

Expression of all genes exhibited tissue bias. Immunohistochemistry confirmed the findings for HHEX, IDE and SLC30A8, which showed strongest tissue-specific mRNA expression bias. Neither age, height nor weight were associated with gene expression. We found no evidence that type 2 diabetes-associated SNPs affect neighbouring gene expression (cis-expression quantitative trait loci) in colon, pancreas and liver.

CONCLUSIONS/INTERPRETATION

This study provides new evidence that tissue-type, but not age, height, weight or SNPs in or near candidate genes associated with increased risk of type 2 diabetes are strong contributors to differential gene expression in the genes and tissues examined.

Trisomy 9 in a Patient with Acute Myelogenous Leukaemia FAB Type M2: A Rare Occurrence

Complete trisomy 9 is a rare cytogenetic abnormality in haematological malignancies. Here we present the case history of a patient with clinical diagnosis of acute myeloblastic leukaemia (FAB type M2) and having trisomy 9 with adverse outcome.

Salbutamol: beware of the paradox!

A 7-year-old known asthmatic presented with an acute severe asthma attack to the Accident and Emergency department. Following a poor response to salbutamol and ipratropium nebulisers, he was given intravenous salbutamol and aminophylline. Over the course of the following 3 h, there was improvement in his bronchospasm with decreasing oxygen requirement, however, his respiratory rate showed an upward trend. Serial blood gas estimations showed a worsening metabolic acidosis unresponsive to two fluid boluses of 20 ml/kg of normal saline. Lactate levels were subsequently measured and found to be high, accounting for the metabolic acidosis. High lactate levels were attributed to intravenous salbutamol. His blood gases and lactate level returned to normal within 3 h after stopping intravenous salbutamol. He was recommended on salbutamol nebulisers while still continuing on intravenous aminophylline. He continued to improve and was discharged home after 4 days.

Efficacy of first-line, WHO recommended generic HAART regimens in Indian children

BACKGROUND

The clinical efficacy of highly active antiretroviral therapy (HAART) in children has been well documented in the developed countries, although most of the regimens are Protease Inhibitor (PI) based which are too expensive. To circumvent this problem World Health Organization (WHO) has recommended Non- Nucleotide Reverse Transcriptase Inhibitor (NNRTI) based regimen for resource-limited countries.

AIM

To assess the long-term efficacy of first line World Health Organization (WHO)-recommended generic highly active antiretroviral therapy (HAART) regimens in treatment -naïve children.

MATERIALS AND METHODS

Observational retrospective analysis was done. Thirty patients on HAART for >or= 6 months were included (27 on Stavudine; three on Zidovudine with Lamivudine/ Nevirapine). No protease inhibitors were used.

RESULTS

Median age was seven years (Interquartile [IQR]: 5.62-8.50) and median duration on HAART was 18 months (IQR: 6-24). No new staging events were observed after six months of initiation of HAART. The median CD4% increased from 6.0 % at baseline to 15.5% at six months, 21.7% at 12 months, 25.4% at 18 months, 24.6 % at 24 months 25.3% at 30 months and 23.7% at 36 months. There was only one case of immunological failure. Stratifi ed analysis based on baseline CD4% show that even patients with a baseline CD4 % of <5% achieved percentage of >25% at 18-24 months and maintained it subsequently. Significant increase in the weight and body mass index Z scores was observed but significant fall in the height Z scores were observed. This sub group of patients with poor linear height velocity would require detailed endocrine evaluation after testing for viral loads.

CONCLUSIONS

Non- Nucleotide Reverse Transcriptase Inhibitor based HAART regimens are feasible and effective in long term in resource-limited setting despite initiation of treatment in advanced stages. These can be continued in NACO/WHO scale up programmes at present for children.

Genetic association analysis of LARS2 with type 2 diabetes

AIMS/HYPOTHESIS

LARS2 has been previously identified as a potential type 2 diabetes susceptibility gene through the low-frequency H324Q (rs71645922) variant (minor allele frequency [MAF] 3.0%). However, this association did not achieve genome-wide levels of significance. The aim of this study was to establish the true contribution of this variant and common variants in LARS2 (MAF > 5%) to type 2 diabetes risk.

METHODS

We combined genome-wide association data (n = 10,128) from the DIAGRAM consortium with independent data derived from a tagging single nucleotide polymorphism (SNP) approach in Dutch individuals (n = 999) and took forward two SNPs of interest to replication in up to 11,163 Dutch participants (rs17637703 and rs952621). In addition, because inspection of genome-wide association study data identified a cluster of low-frequency variants with evidence of type 2 diabetes association, we attempted replication of rs9825041 (a proxy for this group) and the previously identified H324Q variant in up to 35,715 participants of European descent.

RESULTS

No association between the common SNPs in LARS2 and type 2 diabetes was found. Our replication studies for the two low-frequency variants, rs9825041 and H324Q, failed to confirm an association with type 2 diabetes in Dutch, Scandinavian and UK samples (OR 1.03 [95% CI 0.95-1.12], p = 0.45, n = 31,962 and OR 0.99 [0.90-1.08], p = 0.78, n = 35,715 respectively).

CONCLUSIONS/INTERPRETATION

In this study, the largest study examining the role of sequence variants in LARS2 in type 2 diabetes susceptibility, we found no evidence to support previous data indicating a role in type 2 diabetes susceptibility.

Downregulation of the Novel Candidate Tumor Suppressor Gene NCOR2/SMRT in Human Breast Cancer Progression

Background: We recently described a number of DNA copy number changes that differentiated low grade ductal carcinoma in situ (DCIS) lesions with and without associated invasive carcinoma. One of the invasion-associated candidate genes was Nuclear Corepressor 2/Silencing Mediator of Retinoid and Thyroid Receptors (NCOR2/SMRT). This gene is a component of a repressing nuclear receptor complex and a mediator of ER activity. It facilitates recovery from DNA double strand breaks. Previous studies showed that downregulation of the gene was associated with transformation of non-Hodgkin lymphomas.Materials and Methods: Genomic DNA was extracted from microdissected paraffin sections of formalin fixed low grade DCIS lesions with an invasive component (n=42), as well as morphologically similar DCIS lesions without associated invasion within at least 5 years (n=38). Comparative PCR was performed with GAPDH as the reference gene. In addition, we assayed tissue microarrays (TMAs) by immunohistochemistry using two anti-Smrt antibodies. Three TMAs included 162 interpretable cases of invasive breast carcinoma from Roswell Park Cancer Institute (RPCI). One additional TMA included 73 interpretable breast cancers from a previously described cohort from Vienna, Austria. Nuclear staining in neoplastic cells was scored as positive, reduced (significantly weaker compared to admixed benign cells), and negative. Ncor2/Smrt expression was correlated with various patho-biologic variables.Results: Allelic loss of NCOR2/SMRT was observed in 79% (33/42) of DCIS lesions with associated invasion, but in only 26% (10/38) of pure DCIS cases (p&lt;0.01). In the RPCI breast cancer cohort, nuclear Ncor2/Smrt protein was absent or downregulated in 73% (119/162) of tumors. In the Vienna cohort, there was no or markedly reduced nuclear staining in 48% (35/73) of cases. In both cohorts, loss of nuclear reactivity was more common in ER-negative breast cancers. In the Vienna series, Ncor2/Smrt loss was more frequent in PR-negative tumors as well. In the RPCI cohort, Ncor2/Smrt downregulation was more common in ductal (81%, 109/135) than in lobular (37%, 10/27) carcinomas. Neither series showed a significant association between Ncor2/Smrt expression and tumor grade or HER2/neu status.Discussion: Allelic loss of NCOR2/SMRT was significantly more common in DCIS lesions associated with stromal invasion. In invasive tumors, the protein downregulation rate was between 48% and 73%. The gene was more commonly downregulated in ER-negative carcinomas, consistent with its role as a modulator of ER function. Our data provide new evidence that NCOR2/SMRT may play an important part in early breast cancer progression.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3150.

Molecular defects in ITGA2B and ITGB3 genes in patients with Glanzmann thrombasthenia

BACKGROUND

Glanzmann thrombasthenia (GT) is an autosomal recessive inherited platelet function defect that is characterized by reduction in, or absence of, platelet aggregation in response to multiple physiologic agonists. The defect is caused by mutations in the genes encoding ITGA2B or ITGB3. This results in qualitative or quantitative abnormalities of the platelet receptor, alpha IIb-beta 3.

OBJECTIVES

The aim of this study was to identify the mutations in GT patients and to correlate these with patient phenotype.

SUBJECTS AND METHODS

A total of 45 unrelated patients with GT were enrolled in the present study to identify the causative molecular defects, and also to correlate their phenotype with their genotype. Platelet aggregation, flow cytometry, Western blotting, and mutation screening by conformation sensitive gel electrophoresis (CSGE) followed by sequencing were performed in all patients. Novel mutations were analyzed for penetrance in individual families.

RESULTS

A total of 22 novel mutations were identified in 45 unrelated GT patients. Mutations were identified in 36 of the 45 (80%) patients. Missense mutations were seen in most of the GT patients (59%). The remaining mutations were heterogeneous and were distributed throughout the length of the gene. Analysis of family members showed heterozygous mutations in all families.

CONCLUSIONS

The severe type I GT was the most common subtype found in this study. Missense mutations were identified as the defects responsible for most GT patients. Carrier detection and genetic counseling in these families is a potentially effective alternative for decreasing the burden of severe type of GT.

Circulating beta-carotene levels and type 2 diabetes-cause or effect?

AIMS/HYPOTHESIS

Circulating beta-carotene levels are inversely associated with risk of type 2 diabetes, but the causal direction of this association is not certain. In this study we used a Mendelian randomisation approach to provide evidence for or against the causal role of the antioxidant vitamin beta-carotene in type 2 diabetes.

METHODS

We used a common polymorphism (rs6564851) near the BCMO1 gene, which is strongly associated with circulating beta-carotene levels (p = 2 x 10(-24)), with each G allele associated with a 0.27 standard deviation increase in levels. We used data from the InCHIANTI and Uppsala Longitudinal Study of Adult Men (ULSAM) studies to estimate the association between beta-carotene levels and type 2 diabetes. We next used a triangulation approach to estimate the expected effect of rs6564851 on type 2 diabetes risk and compared this with the observed effect using data from 4549 type 2 diabetes patients and 5579 controls from the Diabetes Genetics Replication And Meta-analysis (DIAGRAM) Consortium.

RESULTS

A 0.27 standard deviation increase in beta-carotene levels was associated with an OR of 0.90 (95% CI 0.86-0.95) for type 2 diabetes in the InCHIANTI study. This association was similar to that of the ULSAM study (OR 0.90 [0.84-0.97]). In contrast, there was no association between rs6564851 and type 2 diabetes (OR 0.98 [0.93-1.04], p = 0.58); this effect size was also smaller than that expected, given the known associations between rs6564851 and beta-carotene levels, and the associations between beta-carotene levels and type 2 diabetes.

CONCLUSIONS/INTERPRETATION

Our findings in this Mendelian randomisation study are in keeping with randomised controlled trials suggesting that beta-carotene is not causally protective against type 2 diabetes.