In vivo classification of colorectal neoplasia using high-resolution microendoscopy: Improvement with experience

BACKGROUND AND AIMS

High-resolution microendoscopy (HRME) is a novel, low-cost "optical biopsy" technology that allows for subcellular imaging. The study aim was to evaluate the learning curve of HRME for the differentiation of neoplastic from non-neoplastic colorectal polyps.

METHODS

In a prospective cohort fashion, a total of 162 polyps from 97 patients at a single tertiary care center were imaged by HRME and classified in real time as neoplastic (adenomatous, cancer) or non-neoplastic (normal, hyperplastic, inflammatory). Histopathology was the gold standard for comparison. Diagnostic accuracy was examined at three intervals over time throughout the study; the initial interval included the first 40 polyps, the middle interval included the next 40 polyps examined, and the final interval included the last 82 polyps examined.

RESULTS

Sensitivity increased significantly from the initial interval (50%) to the middle interval (94%, P = 0.02) and the last interval (97%, P = 0.01). Similarly, specificity was 69% for the initial interval but increased to 92% (P = 0.07) in the middle interval and 96% (P = 0.02) in the last interval. Overall accuracy was 63% for the initial interval and then improved to 93% (P = 0.003) in the middle interval and 96% (P = 0.0007) in the last interval.

CONCLUSIONS

In conclusion, this in vivo study demonstrates that an endoscopist without prior colon HRME experience can achieve greater than 90% accuracy for identifying neoplastic colorectal polyps after 40 polyps imaged. HRME is a promising modality to complement white light endoscopy in differentiating neoplastic from non-neoplastic colorectal polyps.

Quantitative evaluation of in vivo vital-dye fluorescence endoscopic imaging for the detection of Barrett's-associated neoplasia

Current imaging tools are associated with inconsistent sensitivity and specificity for detection of Barrett's-associated neoplasia. Optical imaging has shown promise in improving the classification of neoplasia in vivo. The goal of this pilot study was to evaluate whether in vivo vital dye fluorescence imaging (VFI) has the potential to improve the accuracy of early-detection of Barrett's-associated neoplasia. In vivo endoscopic VFI images were collected from 65 sites in 14 patients with confirmed Barrett's esophagus (BE), dysplasia, oresophageal adenocarcinoma using a modular video endoscope and a high-resolution microendoscope(HRME). Qualitative image features were compared to histology; VFI and HRME images show changes in glandular structure associated with neoplastic progression. Quantitative image features in VFI images were identified for objective image classification of metaplasia and neoplasia, and a diagnostic algorithm was developed using leave-one-out cross validation. Three image features extracted from VFI images were used to classify tissue as neoplastic or not with a sensitivity of 87.8% and a specificity of 77.6% (AUC = 0.878). A multimodal approach incorporating VFI and HRME imaging can delineate epithelial changes present in Barrett's-associated neoplasia. Quantitative analysis of VFI images may provide a means for objective interpretation of BE during surveillance.

Intersection of population variation and autoimmunity genetics in human T cell activation

T lymphocyte activation by antigen conditions adaptive immune responses and immunopathologies, but we know little about its variation in humans and its genetic or environmental roots. We analyzed gene expression in CD4(+) T cells during unbiased activation or in T helper 17 (T(H)17) conditions from 348 healthy participants representing European, Asian, and African ancestries. We observed interindividual variability, most marked for cytokine transcripts, with clear biases on the basis of ancestry, and following patterns more complex than simple T(H)1/2/17 partitions. We identified 39 genetic loci specifically associated in cis with activated gene expression. We further fine-mapped and validated a single-base variant that modulates YY1 binding and the activity of an enhancer element controlling the autoimmune-associated IL2RA gene, affecting its activity in activated but not regulatory T cells. Thus, interindividual variability affects the fundamental immunologic process of T helper activation, with important connections to autoimmune disease.

Comparison of aviary, barn and conventional cage raising of chickens on laying performance and egg quality

This study intended to compare the productive performance of three different layer raising systems; conventional cage (CC), barn (BR) and aviary (AV). The AV is welfare bestowed housing that allows free locomotion for birds within the BR. The BR allows bird's free locomotion inside BR but without multilevel structures. Both pullets and cockerels were housed together in both AV and BR, but only pullets in CC. Seventeen weeks old Lohmann Brown Lite (n = 800) pullets were housed in AV during this study. The same age layer pullets were simultaneously assigned to either at CC or BR to compare egg production performance with AV. The duration of experiment was 40 weeks (from 21st to 60th week). There were no remarkable differences in egg production, hen day egg production (HDEP) and average egg weight among three rearing systems. First 20 weeks (phase-1) average HDEP (%) of AV, CC, and BR were 85.9, 88.8, 87.1 and average egg weights (g) were 57.5, 59.9, and 56.9 respectively. Those of the remaining 20 weeks (phase-2) were 87.1, 87.9, 85.5 and 64.2, 63.0 62.1, respectively. Daily feed intakes (122 g, 110 g, 125 g); feed conversion ratio (2.4, 2.1, 2.5) and daily egg mass (53.9 g, 54.4 g, 52.8 g) data from AV, CC, and BR were not influenced significantly by the respective raising systems. Daily feed intake of layers in both AV (124 g) and BR (127 g) tended to be higher than that in CC (113 g) during phase-2. Overall, exterior egg quality (dirty and cracked eggs) in both phases was superior in BR compared with AV and CC, whereas CC generated intermediate results. This study indicated that the HDEP per se in AV and BR were not significantly different from that in CC. The study implied that the facility depreciation cost for AV and cost for increased feed intake in AV compared to CC are believed to be critical to evaluate the cost effectiveness of egg production in AV.

Diagnosis of neoplasia in Barrett's esophagus using vital-dye enhanced fluorescence imaging

The ability to differentiate benign metaplasia in Barrett's Esophagus (BE) from neoplasia in vivo remains difficult as both tissue types can be flat and indistinguishable with white light imaging alone. As a result, a modality that highlights glandular architecture would be useful to discriminate neoplasia from benign epithelium in the distal esophagus. VFI is a novel technique that uses an exogenous topical fluorescent contrast agent to delineate high grade dysplasia and cancer from benign epithelium. Specifically, the fluorescent images provide spatial resolution of 50 to 100 μm and a field of view up to 2.5 cm, allowing endoscopists to visualize glandular morphology. Upon excitation, classic Barrett's metaplasia appears as continuous, evenly-spaced glands and an overall homogenous morphology; in contrast, neoplastic tissue appears crowded with complete obliteration of the glandular framework. Here we provide an overview of the instrumentation and enumerate the protocol of this new technique. While VFI affords a gastroenterologist with the glandular architecture of suspicious tissue, cellular dysplasia cannot be resolved with this modality. As such, one cannot morphologically distinguish Barrett's metaplasia from BE with Low-Grade Dysplasia via this imaging modality. By trading off a decrease in resolution with a greater field of view, this imaging system can be used at the very least as a red-flag imaging device to target and biopsy suspicious lesions; yet, if the accuracy measures are promising, VFI may become the standard imaging technique for the diagnosis of neoplasia (defined as either high grade dysplasia or cancer) in the distal esophagus.

Common genetic variants modulate pathogen-sensing responses in human dendritic cells

Little is known about how human genetic variation affects the responses to environmental stimuli in the context of complex diseases. Experimental and computational approaches were applied to determine the effects of genetic variation on the induction of pathogen-responsive genes in human dendritic cells. We identified 121 common genetic variants associated in cis with variation in expression responses to Escherichia coli lipopolysaccharide, influenza, or interferon-β (IFN-β). We localized and validated causal variants to binding sites of pathogen-activated STAT (signal transducer and activator of transcription) and IRF (IFN-regulatory factor) transcription factors. We also identified a common variant in IRF7 that is associated in trans with type I IFN induction in response to influenza infection. Our results reveal common alleles that explain interindividual variation in pathogen sensing and provide functional annotation for genetic variants that alter susceptibility to inflammatory diseases.

Does the DVR(®) plate restore bony anatomy following distal radius fractures?

INTRODUCTION

Fractures of the distal radius are common. Malreduced fractures are associated with residual functional deficiency. There has been a trend over the last few years for using fixed angle volar locking plates to surgically stabilise this injury. Our unit uses the DVR^® plate (DePuy, Warsaw, IN, US). Nevertheless, it is unknown whether the normal bony anatomy is recreated or merely restored to acceptable limits with its usage. The aim of this study was to evaluate the reduction achieved compared with an uninjured population and pre-existing quoted ‘normal’ values. Furthermore, we wanted to identify the percentage of cases that were reduced to acceptable limits, and determine whether the grade of the surgeon and fracture type was a confounding influence on this reduction.

METHODS

A retrospective review of the 3-month postoperative radiography of 48 eligible patients who underwent open reduction and internal fixation of a distal radius fracture with a DVR^® plate was undertaken.

RESULTS

Volar tilt, radial length and inclination were different to quoted normal values (p<0.01). Despite this, these parameters fell within acceptable limits in 46 cases; this was not influenced by fracture type or grade of operating surgeon.

CONCLUSIONS

The DVR^® plate restores the bony anatomy to within acceptable limits in the majority of patients who have sustained a fracture of the distal radius although of all parameters investigated, the widest variability is seen in volar tilt.

In vivo diagnostic accuracy of high-resolution microendoscopy in differentiating neoplastic from non-neoplastic colorectal polyps: a prospective study

OBJECTIVES

High-resolution microendoscopy (HRME) is a low-cost, "optical biopsy" technology that allows for subcellular imaging. The purpose of this study was to determine the in vivo diagnostic accuracy of the HRME for the differentiation of neoplastic from non-neoplastic colorectal polyps and compare it to that of high-definition white-light endoscopy (WLE) with histopathology as the gold standard.

METHODS

Three endoscopists prospectively detected a total of 171 polyps from 94 patients that were then imaged by HRME and classified in real-time as neoplastic (adenomatous, cancer) or non-neoplastic (normal, hyperplastic, inflammatory).

RESULTS

HRME had a significantly higher accuracy (94%), specificity (95%), and positive predictive value (PPV, 87%) for the determination of neoplastic colorectal polyps compared with WLE (65%, 39%, and 55%, respectively). When looking at small colorectal polyps (less than 10 mm), HRME continued to significantly outperform WLE in terms of accuracy (95% vs. 64%), specificity (98% vs. 40%) and PPV (92% vs. 55%). These trends continued when evaluating diminutive polyps (less than 5 mm) as HRME's accuracy (95%), specificity (98%), and PPV (93%) were all significantly greater than their WLE counterparts (62%, 41%, and 53%, respectively).

CONCLUSIONS

In conclusion, this in vivo study demonstrates that HRME can be a very effective modality in the differentiation of neoplastic and non-neoplastic colorectal polyps. A combination of standard white-light colonoscopy for polyp detection and HRME for polyp classification has the potential to truly allow the endoscopist to selectively determine which lesions can be left in situ, which lesions can simply be discarded, and which lesions need formal histopathologic analysis.

Abstract P1-01-19: Role of axillary clearance with tumor positive sentinel node in mastectomy group: Is the results of ACOSOG Z0011 trial adaptable to mastectomy patient?

Background: Recent data from ACOSOG Z0011 trial or AMAROS trial suggest that axillary lymph node dissection(ALND) may be unnecessary for patients with positive sentinel lymph node biopsy(SLNB) receiving breast conserving surgery(BCS) with irradiation. However, consensus statements and guidelines until recently recommended that patients with mastectomy and tumor positive sentinel node undergo completion ALND. In this preliminary study, we compared these patients who did not undergo ALND with the patients who received BCS with SLNB only and irradiation and we analyzed the locoregional recurrence rate to show no differences of outcomes between two groups.

Method: We identified 6,163 women with invasive breast cancer who underwent surgical resection at the National Cancer Center (Goyang,Gyeonggi-do,Korea) between January 2000 to December 2011. Clinico-pathological data obtained from prospective collecting medical database of our institution were analyzed retrospectively. The mastectomy with positive SLNB group was 47 patients and BCS with positive SLNB and irradiation group was 172 patients. The primary end point was loco-regional recurrence rate.

Result : Clinical and tumor characteristics were similar between two groups except T stage and receptor status. The mean tumor size was 5.5cm with mastectomy group and 3.5cm with BCS group. The median number of nodes removed was three. There was not a single case of locoregional recurrence in both groups. At a median follow-up of 53.5 months (last follow-up, May 2013), 5-year overall survival was 85.7% with mastectomy and 97.3% with BCS group.

Conclusion : In our study, there was no case of locoregional recurrence as above. This results lend weight to the argument that SLNB without ALND may be reasonable management for selected patients with appropriate surgery and adjuvant systemic therapy. This study can be regarded as a preliminary study with a sufficient value despite of the prognosis showed some statistical differences between two groups. It resides in the difference of initial stage of patients of two groups. We will present additional data compared with the mastectomy with axillary clearance group at the meeting.

Acknowledgement This work was supported by grant from the National Cancer Center Korea (1210331-2).

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-01-19.

Abstract OT3-1-08: The PROCEED trial KCSG BR11-01: Phase III multicenter randomized open label study of irinotecan plus capecitabine versus capecitabine in patients previously treated with anthracycline and taxane for HER2 negative metastatic breast cancer

Background: Most patients with metastatic breast cancer (MBC) experience disease progression after being treated with an anthracycline or taxane. Irinotecan, a semisynthetic agent derived from the natural alkaloid camptothecin is metabolized to the active metabolite SN-38 which targets topoisomerase I leading to single and double strand DNA breaks. Irinotecan as a single agent demonstrated tumor activity with an objective response rate ranging from 5 to 23% in patients with MBC refractory to taxane and anthracycline. Irinotecan increased the activity of 5-FU, the active metabolite of capecitabine, and overcomes the negative effect of thymidylate synthase overexpression, which is the main target of an active metabolite of 5-FU. A phase II study that evaluated the efficacy and safety of irinotecan and capecitabin combination (IX) showed that the median progression free survival (PFS) was 7.6 months (95% CI, 5.0-10.2months), and the median OS was 22.6 months (95% CI, 15.4 – 29.8 months) with good tolerability in anthracycline and taxane pretreated MBC patients. Based on these results, we planned to conduct a multicenter, randomized phase III study which assesses the efficacy of irinotecan and capecitabine combination therapy compared with capecitabine alone in patients with anthracycline and taxane resistant MBC.

Methods: In this trial, patients with HER2 normal tumor who previously received anthracycline and taxane based chemotherapies are enrolled. Eligible patients are randomly assigned in a 1:1 ratio to receive irinotecan plus capecitabine or capecitabine alone. The primary end point of this trial is PFS and a total number of accrual patients will be 222. Randomization is done using a random block size permutation method and stratified by hormone receptor status (negative vs. positive), first line vs. ≥second lines, visceral metastasis (negative vs. positive). Patients receive irinotecan at 80 mg/m2 on day 1 and 8 every 3 weeks and capecitabine 1000mg/m2 bid from day 1 to day 14 every 3 weeks. In control arm, patients receive capecitabine 1250mg/m2 bid from day 1 to day 14 every 3 weeks. Response will be assessed using RECIST1.1 criteria and toxicity will be graded according to NCI-CTCAE 4.0 criteria. Study Status: A total of 107 patients consented for the study since June 2011, and accrual is ongoing. Clinical trial information: NCT01501669.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT3-1-08.

Abstract P3-08-14: Could the preoperative systemic therapy be a risk factor for breast cancer-related lymphedema in stage II/III breast cancer?

Background: The breast cancer-related lymphedema (LE) has been known to be closely related to axillary lymph nodes dissection (ALND), chemotherapy, and radiation therapy. In this study, we evaluated whether the sequence of systemic chemotherapy and surgery could be a predictive factor in stage II/III breast cancer.

Methods and Materials: A total of 867 patients with stage II/III breast cancer, who underwent curative surgery with adequate systemic therapy from 2004 to 2009, were retrospectively analyzed. Adjuvant chemotherapy (ACT) was performed in 571 patients (65.9%) and preoperative systemic chemotherapy (PSC) in 296 (34.1%). We evaluated the incidence of LE by clinicopathologic factors and treatments.

Results: At a median follow-up of 5.1 years (range, 3.0-8.3 years), 360 patients (41.5%) had experienced LE, 244 patients have retained LE (permanent LE), and 116 patents were normalized. The overall 5-year cumulative incidence of LE was 17%. LE occurred in 188 patients (32.9%) in patients with ACT, 172 patients (58.1%) with PSC (P&lt;0.001), permanent LE in 121 (21.2%) with ACT, 123 (41.6%) with PSC (P&lt;0.001), respectively. Multivariate analysis showed that PSC (hazard ratio [HR], 1.65; P&lt;.001), radiotherapy (HR, 2.24; P&lt;0.01), ALND (HR, 1.41; P = 0.04), and nodal stage (HR, 1.93; P = 0.04) were independent risk factors for LE occurrence. For the permanent LE, PSC (HR, 1.44; P = 0.05), radiotherapy (HR, 2.79; P&lt;0.01), ALND (HR, 1.77; P&lt;0.01), and nodal stage (HR, 3.01; P = 0.02) showed the associations.

Conclusions: The risk factors associated with LE were advanced stage, ALND and radiotherapy. PSC was one of predictors for transients LE. However, further evaluation should be done whether it is a risk factor for permanent LE.

This research was supported by National Cancer Center Grant NCC-1210181-2 by the National Cancer Center, Republic of Korea.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-08-14.

Analysis of immune-related loci identifies 48 new susceptibility variants for multiple sclerosis

Using the ImmunoChip custom genotyping array, we analyzed 14,498 subjects with multiple sclerosis and 24,091 healthy controls for 161,311 autosomal variants and identified 135 potentially associated regions (P < 1.0 × 10(-4)). In a replication phase, we combined these data with previous genome-wide association study (GWAS) data from an independent 14,802 subjects with multiple sclerosis and 26,703 healthy controls. In these 80,094 individuals of European ancestry, we identified 48 new susceptibility variants (P < 5.0 × 10(-8)), 3 of which we found after conditioning on previously identified variants. Thus, there are now 110 established multiple sclerosis risk variants at 103 discrete loci outside of the major histocompatibility complex. With high-resolution Bayesian fine mapping, we identified five regions where one variant accounted for more than 50% of the posterior probability of association. This study enhances the catalog of multiple sclerosis risk variants and illustrates the value of fine mapping in the resolution of GWAS signals.

Fibroblast growth factor 21 improves insulin resistance and ameliorates renal injury in db/db mice

Despite the emerging importance of fibroblast growth factor 21 (FGF21) as a metabolic hormone regulating energy balance, its direct effects on renal function remain unexplored. FGF21 was injected ip daily for 12 weeks into db/db mice. Compared with control vehicle injection, FGF21 treatment significantly improved lipid profiles and insulin resistance and resulted in significantly higher serum adiponectin levels. In contrast, serum insulin and 8-isoprostane levels were significantly decreased. Interestingly, FGF21 and its receptor components in the kidneys were found to be significantly up-regulated in db/db mice, which suggests an FGF21-resistant state. FGF21 treatment significantly down-regulated FGF21 receptor components and activated ERK phosphorylation. FGF21 administration also markedly decreased urinary albumin excretion and mesangial expansion and suppressed profibrotic molecule synthesis. Furthermore, FGF21 improved renal lipid metabolism and oxidative stress injury. In cultured renal cells, FGF21 was mainly expressed in mesangial cells, and knockdown of FGF21 expression by stealth small interfering RNA further aggravated high-glucose-induced profibrotic cytokine synthesis in mesangial cells. Our results suggest that FGF21 improves insulin resistance and protects against renal injury through both improvement of systemic metabolic alterations and antifibrotic effects in type 2 diabetic nephropathy. Targeting FGF21 could therefore provide a potential candidate approach for a therapeutic strategy in type 2 diabetic nephropathy.

Re-categorisation of male lower urinary tract symptoms based on the international prostate symptom score questionnaire

AIMS

The purpose of this study was to develop a new sub-classification system for male lower urinary tract symptoms (LUTS)-mild, moderate and severe-using the conventional International Prostate Symptoms Score (I-PSS).

METHODS

From October 2007 to March 2012, a total of 2234 male patients (≥ 50 years old) presenting with LUTS were enrolled in this study. Patients were sorted according to their I-PSS (ranging from 1 to 35 points) and divided into three groups based on their quality of life (QoL) score. A chi-square automatic interaction detection (CHAID) algorithm, based on adjusted significance testing, was used. The Kappa coefficient was calculated for the agreement of original and new categorisation.

RESULTS

Mean total I-PSS and QoL scores were 11.0 and 2.9 respectively. According to the original classification, 838 patients (38.6%) had mild, 1053 (48.5%) had moderate and 282 (13.0%) had severe symptoms. After the CHAID algorithm was applied, the scores were re-categorised as 'mild' (1-6 points), 'moderate' (7-21 points) and 'severe' (22-35 points). The overall model was able to correctly predict whether an I-PSS was associated with mild, moderate or severe symptoms, with 70.1% accuracy. According to this new classification, 704 patients (32.4%) were shown to have mild, 1255 (57.8%) to have moderate and 214 (9.8%) to have severe LUTS. The agreement of conventional and new categorisation is very strong (Kappa coefficient = 0.84).

CONCLUSIONS

Conventional categorisation of LUTS by I-PSS needs to be updated and the category of moderate LUTS should be broadened.

RAF kinase inhibitor-independent constitutive activation of Yes-associated protein 1 promotes tumor progression in thyroid cancer

The transcription coactivator Yes-associated protein 1 (YAP1) is regulated by the Hippo tumor suppressor pathway. However, the role of YAP1 in thyroid cancer, which is frequently associated with the BRAF^V600E mutation, remains unknown. This study aimed to investigate the role of YAP1 in thyroid cancer. YAP1 was overexpressed in papillary (PTC) and anaplastic thyroid cancer, and nuclear YAP1 was more frequently detected in BRAF^V600E (+) PTC. In the thyroid cancer cell lines TPC-1 and HTH7, which do not have the BRAF^V600E mutation, YAP1 was cytosolic and inactive at high cell densities. In contrast, YAP1 was retained in the nucleus and its target genes were expressed in the thyroid cancer cells 8505C and K1, which harbor the BRAF^V600E mutation, regardless of cell density. Furthermore, the nuclear activation of YAP1 in 8505C was not inhibited by RAF or MEK inhibitor. In vitro experiments, YAP1 silencing or overexpression affected migratory capacities of 8505C and TPC-1 cells. YAP1 knockdown resulted in marked decrease of tumor volume, invasion and distant metastasis in orthotopic tumor xenograft mouse models using the 8505C thyroid cancer cell line. Taken together, YAP1 is involved in the tumor progression of thyroid cancer and YAP1-mediated effects might not be affected by the currently used RAF kinase inhibitors.

Gene delivery of c-myb increases bone formation surrounding oral implants

Bone regeneration around titanium (Ti) implants is a relatively slow process. The c-myb transcription factor has been associated with high proliferation and differentiation rates in bone. This study analyzed whether c-myb can enhance new bone surrounding the implant. In vitro overexpressed chitosan-gold nanoparticles conjugated with plasmid DNA/c-myb (Ch-GNPs/c-myb)-coated Ti surfaces were associated with enhanced expression of the osteogenic molecules osteopontin (OPN), runt-related transcription factor 2 (RUNX-2), and bone morphogenetic proteins (BMP2/7) in MC-3T3E1 osteoblast cells. Further, to determine its in vivo effect, we inserted Ch-GNPs/c-myb-coated Ti implants into rat mandibles. One and 4 wks post-implantation, mandibles were examined by microcomputed tomography, immunohistochemistry, and hematoxylin & eosin staining. The microcomputed tomography analysis demonstrated that c-myb overexpression increased the density and volume of newly formed bone surrounding the implants, compared with those in controls (p < .05). Further, c-myb increased the number of cells expressing BMP2/7 and aided in the increase of new bone (p < .05). These results support the view that c-myb overexpression accelerates new bone surrounding implants and can serve as a potent molecule in promoting tissue regeneration around dental implants. The recipient rat used in this system provides an excellent in vivo model for studies of bone regeneration.

Renal protective effects of toll-like receptor 4 signaling blockade in type 2 diabetic mice

Chronic inflammation caused by high glucose and high free fatty acid (FFA) concentrations is a major contributor to the pathogenesis of type 2 diabetes. Recent evidence suggests that activation of Toll-like receptor (TLR) signaling induces peripheral insulin resistance and mediates central insulin and leptin resistance. In this study, we investigated the renal effects of TLR4 signaling blockade in type 2 diabetic mice. Eight-week-old db/db mice were treated for 12 weeks with (S,R)-3-phenyl-4,5-dihydro-5-isoxasole acetic acid (GIT27), which targets macrophages through the inhibition of TLR4- and TLR2/6-mediated signaling pathways. Although GIT27 treatment improved glycemic control and insulin tolerance, which is associated with a lower lipid profile, it did not impact body weight or food consumption. GIT27 treatment also markedly decreased urinary albumin excretion, decreased proinflammatory cytokine synthesis, improved tissue lipid metabolism, induced oxidative stress, and improved glomerulosclerosis compared with the control db/db group. In cultured podocytes and adipocytes, high glucose levels with FFA stimulation increased TLR4 expression and proinflammatory cytokine synthesis, but the effects were abolished by GIT27 treatment. In addition, knockdown of TLR4 expression by stealth small interfering RNA abolished FFA-induced proinflammatory cytokine synthesis in cultured podocytes. In conclusion, our results suggest that GIT27 treatment improves insulin resistance and protects against the renal injury that occurs in type 2 diabetic nephropathy through both metabolic and antiglomerulosclerotic mechanisms. These results suggest that TLR pathway inhibition might play a direct protective role in diabetic kidney disease.

RNH1 regulation of reactive oxygen species contributes to histone deacetylase inhibitor resistance in gastric cancer cells

Histone deacetylase inhibitors (HDACis) are a promising class of anticancer epigenetic drugs, however, molecular factors influencing the responses of individual tumors to HDACi therapies remain obscure. Here, we sought to identify genes associated with HDACi resistance in gastric cancer. Treating a panel of 17 gastric cancer cell lines with multiple HDACi compounds (trichostatin A, SAHA and MS275), we identified two distinct classes of lines exhibiting either HDACi sensitivity or resistance. Genomic comparisons between the sensitive and resistant classes using two independent microarray platforms identified RNH1, encoding a ribonuclease inhibitor, as a gene highly expressed in HDACi-resistant lines. Using genetic knockdown and overexpression assays, we show that RNH1 is both necessary and sufficient to induce HDACi resistance, and that RNH1 is likely to mediate this resistance through the dampening of HDACi-induced reactive oxygen species (ROS) in cancer cells. The discovery of RNH1 as a regulator of HDACi resistance in gastric cancer highlights a functional role for ROS induction in the cellular effects of this important drug class.

Modular video endoscopy for in vivo cross-polarized and vital-dye fluorescence imaging of Barrett's-associated neoplasia

A modular video endoscope is developed and tested to allow imaging in different modalities. This system incorporates white light imaging (WLI), cross-polarized imaging (CPI), and vital-dye fluorescence imaging (VFI), using interchangeable filter modules. CPI and VFI are novel endoscopic modalities that probe mucosal features associated with Barrett's neoplasia. CPI enhances vasculature, while VFI enhances glandular architecture. In this pilot study, we demonstrate the integration of these modalities by imaging areas of Barrett's metaplasia and neoplasia in an esophagectomy specimen. We verify that those key image features are also observed during an in vivo surveillance procedure. CPI images demonstrate improved visualization of branching blood vessels associated with neoplasia. VFI images show glandular architecture with increased glandular effacement associated with neoplasia. Results suggests that important pathologic features seen in CPI and VFI are not visible during standard endoscopic white light imaging, and thus the modalities may be useful in future in vivo studies for discriminating neoplasia from Barrett's metaplasia. We further demonstrate that the integrated WLI/CPI/VFI endoscope is compatible with complementary high-resolution endomicroscopy techniques such as the high-resolution microendoscope, potentially enabling two-step ("red-flag" widefield plus confirmatory high-resolution imaging) protocols to be enhanced.

Abstract PD09-05: Single nucleotide polymorphism of XRCC1 which participates in DNA repair mechanism predicts clinical outcome in relapsed or metastatic breast cancer patients treated with S1 and oxaliplatin chemotherapy: Results from multicenter prospective study (TORCH_KCSG BR07-03)

Background: S1 and oxaliplatin (SOX) combination chemotherapy is an effective regimen in anthracycline and taxane pretreated metastatic breast cancer (MBC) patients with manageable toxicities (KCSG BR07-03, SABCS 2011 #Abst P3-16-06). The aim of this study was to investigate the association of the single nucleotide polymorphisms (SNPs) and clinical outcome in MBC treated with SOX chemotherapy.

Patients and Methods: A total of 87 MBC patients previously treated with or resistant to anthracycline and taxane chemotherapy were enrolled in this prospective multicenter trial. The patients received S-1 80mg/m2/day (day 1–14) and oxaliplatin 130 mg/m2 (day 1) every 3 weeks till progression. Among the 87 patients, 77 patients were available for SNP analysis. Germline DNA from peripheral blood (PB) mononuclear cells was extracted. SNPs in 4 genes from pathways that may influence cellular sensitivity to S1 and oxaliplatin (TS, ERCC, XPD, and XRCC) were genotyped from PB sample using PCR-restriction fragment length polymorphism.

Results: Overall response rate (RR) was 38.5% (95% CI: 27.7–49.3) and disease control rate was 67.9% (95% CI:57.5–78.3) to SOX. Median time-to-progression (TTP) and overall survival (OS) were 6.0 mo (95% CI: 5.1–6.9 mo) and 19.4 mo (95% CI: not estimated), respectively. XRCC1 Arg194Trp SNP which participates in DNA repair mechanism showed correlation with the clinical outcome. RR was tend to higher in XRCC1 Arg194Trp CC genotype compared with CT or TT genotype (50.0 % vs 35.1% or 12.5%, P = 0.121). TTP of patients with CC genotype in XRCC1 Arg194Trp was significantly longer than the TTP of patients with CT or TT genotype (median TTP: 6.4 mo in CC, 5.9 mo in CT, 3.0 mo in TT, P = 0.007) as well as overall survival (OS) (median OS: not reached in CC, 13.9 mo in CT, 7.1 mo in TT, P = 0.006). After adjusting for hormone receptor status, performance status, and visceral involvement, prognostic value of XRCC1 Arg194Trp SNP remained significant (Hazard Ratio=1.322 and 4.484, P = 0.016). Other SNPs were not significantly associated with survival or toxicities.

Conclusion: XRCC1 Arg194Trp SNP is associated with clinical outcome of MBC patients treated with SOX chemotherapy. Further studies of the relationship between germline polymorphisms in XRCC1 and functional mechanism researches are warranted.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD09-05.

Probing charge transport in oxidatively damaged DNA sequences under the influence of structural fluctuations

We present a detailed study of the charge transport characteristics of double-stranded DNA oligomers including the oxidative damage 7,8-dihydro-8-oxoguanine (8-oxoG). The problem is treated by a hybrid methodology combining classical molecular dynamics simulations and semiempirical electronic structure calculations to formulate a coarse-grained charge transport model. The influence of solvent- and DNA-mediated structural fluctuations is encoded in the obtained time series of the electronic charge transfer parameters. Within the Landauer approach to charge transport, we perform a detailed analysis of the conductance and current time series obtained by sampling the electronic structure along the molecular dynamics trajectory, and find that the inclusion of 8-oxoG damages into the DNA sequence can induce a change in the electrical response of the system. However, solvent-induced fluctuations tend to mask the effect, so that a detection of such sequence modifications via electrical transport measurements in a liquid environment seems to be difficult to achieve.

Resting-state fMRI: a review of methods and clinical applications

SUMMARY

Resting-state fMRI measures spontaneous low-frequency fluctuations in the BOLD signal to investigate the functional architecture of the brain. Application of this technique has allowed the identification of various RSNs, or spatially distinct areas of the brain that demonstrate synchronous BOLD fluctuations at rest. Various methods exist for analyzing resting-state data, including seed-based approaches, independent component analysis, graph methods, clustering algorithms, neural networks, and pattern classifiers. Clinical applications of resting-state fMRI are at an early stage of development. However, its use in presurgical planning for patients with brain tumor and epilepsy demonstrates early promise, and the technique may have a future role in providing diagnostic and prognostic information for neurologic and psychiatric diseases.

Advanced endoscopic imaging for Barrett's Esophagus: current options and future directions

Barrett's esophagus is the precursor to esophageal adenocarcinoma, one of the most rapidly increasing cancers in the United States. Given the poor prognosis of late-stage adenocarcinoma, endoscopic surveillance is recommended for subjects with Barrett's esophagus to detect early neoplasia. Current guidelines recommend "random" four-quadrant biopsies taken every 1-2 cm throughout the Barrett's segment. However, this only samples a minority of epithelium and has been shown to miss areas of endoscopically- inapparent neoplasia (high grade dysplasia or cancer). Recent efforts have focused on developing novel diagnostic imaging technologies to detect the subtle epithelial changes associated with dysplasia and neoplasia in Barrett's esophagus. Some of these modalities serve as "red flag" technologies designed to detect areas of abnormality within large surface areas. Other technologies serve to characterize areas of visible abnormality, offering a higher spatial resolution to confirm/exclude the presence of neoplasia. This review summarizes several available and evolving imaging technologies used in the endoscopic diagnosis and surveillance of Barrett's associated neoplasia.

MRI to differentiate benign from malignant soft-tissue tumours of the extremities: a simplified systematic imaging approach using depth, size and heterogeneity of signal intensity

OBJECTIVE

Differentiating between malignant and benign lesions on the basis of MR images depends on the experience of the radiologist. For non-experts, we aimed to develop a simplified systematic MRI approach that uses depth, size and heterogeneity on T(2) weighted MR images (T(2)WI) to differentiate between malignant and benign lesions, and evaluated its diagnostic accuracy.

METHODS

MR images of 266 patients with histologically proven soft-tissue tumours of the extremities (102 malignant, 164 benign) were analysed according to depth (superficial or deep), size (<50, ≥50 mm) and signal intensity (homogeneous or heterogeneous) on T(2)WI, to determine the ability of each to predict benign and malignant tumours. These three parameters were categorised into systematic combinations of different orders of application, and each combination was assessed for its ability to differentiate between benign and malignant lesions.

RESULTS

Univariate analysis showed that depth, size and heterogeneity on T(2)WI differed significantly between benign and malignant masses (p<0.0001 each). Multiple logistic regression analysis, however, showed that depth was not helpful in distinguishing benign from malignant lesions. The systematic combination of signal intensity, size and depth, in that order, was superior to other combinations, resulting in higher diagnostic values for malignancy, with a sensitivity of 64%, a specificity of 85%, a positive predictive value of 32%, a negative predictive value of 59% and an accuracy of 77%.

CONCLUSION

A simplified systematic imaging approach, in the order signal intensity, size and depth, would be a reference to distinguish between benign and malignant soft-tissue tumours for non-experts.