GLT-1 overexpression attenuates bladder nociception and local/cross-organ sensitization of bladder nociception

Glutamatergic pathways mediate transmission of pain. Strategies to reduce glutamatergic neurotransmission may have beneficial effects to mitigate nociception. Recent work revealed that overexpression of the astrocytic glutamate transporter (GLT-1) by transgenic or pharmacologic approaches produced a diminished visceral nociceptive response to colonic distension. The purpose of this study was to determine the effect of GLT-1 overexpression on the visceromotor response to bladder distension. Increased glutamate uptake activity produced by 1-wk ceftriaxone (CTX) treatment attenuated 60-64% the visceromotor response to graded bladder distension compared with vehicle-treated mice. One-hour pretreatment with selective GLT-1 antagonist dihydrokainate reversed the blunted visceromotor response to bladder distension produced by 1-wk CTX, suggesting that GLT-1 overexpression mediated the analgesic effect of CTX. Moreover, sensitization of the visceromotor response to bladder distension produced by local bladder irritation (acrolein) was also attenuated by 1-wk CTX treatment. A model of cross-organ sensitization of bladder visceromotor response to distension was next studied to determine whether increased expression of GLT-1 can mitigate colon to bladder sensitization. Intracolonic trinitrobenzene sulfonic acid (TNBS) administered 1 h before eliciting the visceromotor response to graded bladder distension produced a 75-138% increase in visceromotor response compared with animals receiving intracolonic vehicle. In marked contrast, animals treated with 1-wk CTX + intracolonic TNBS showed no enhanced visceromotor response compared with the 1-wk vehicle + intracolonic vehicle group. The study suggests that GLT-1 overexpression attenuates the visceromotor response to bladder distension and both local irritant-induced and cross-organ-sensitized visceromotor response to bladder distension.

Human papillomavirus 16 or 18 infection and prostate cancer risk: a meta-analysis

OBJECTIVE

Whether the oncogenic human papillomavirus (HPV) infection, especially infection with the most common subtypes 16 or 18, is related to prostate carcinogenesis remains conflicting. A meta-analysis with updated data was performed to obtain a more precise estimate of the association between them.

METHODS

Eligible studies were retrieved via both computer searches and review of references. The relation of HPV-16 or HPV-18 infection to prostate cancer (PC) was quantified separately. Stratified analyses based on HPV detection methods and geographic regions were also performed. Estimates of OR with 95% CI were summarized using the fixed-effect or random-effect models as appropriate.

RESULTS

Twenty-five eligible studies were retrieved. All the 25 studies were assigned for exploring the relation of HPV-16 infection to PC, while 13 studies provided additional information on HPV-18 simultaneously. In the overall estimates, the pooled OR indicated no significant increase of PC risk related with either HPV-16 (OR 1.09; 95% CI 0.97-1.23; P(heterogeneity) = 0.135) or HPV-18 (OR 1.05; 95% CI 0.89-1.24; P(heterogeneity) = 0.314) infection. Further quantitative assay of stratified data could also not yield any significant result, except the stratified analysis on HPV-16 DNA detection, which revealed higher HPV-16 DNA prevalence in PC cases (OR 1.54; 95% CI 1.07-2.20; P(heterogeneity) = 0.130).

CONCLUSIONS

Even though the overall estimates did not provide a supportive evidence for the causal role of HPV in prostate carcinogenesis, higher HPV-16 DNA prevalence in PC cases from the stratified analysis still indicated a potential association between HPV infection and PC risk in our meta-analysis.

Relationship between plasma pazopanib concentration and incidence of adverse events in renal cell carcinoma

345

Background: Pazopanib (P), an oral angiogenesis inhibitor targeting VEGFR, PDGFR, and c-Kit, is approved by the US FDA for the treatment of advanced renal cell cancer (mRCC). Exploratory analyses of data from a Ph II mRCC study (Hutson T, J Clin Oncol. 27, 2009:1) indicated that 70% of patients (pt) receiving 800mg once daily had a week (wk) 4 plasma P trough (Cmin) >20.6μ g/mL that is associated with improved efficacy (Suttle B, J Clin Oncol. 28, 2010:S3048). In this further analysis of the dataset, we investigated the relation between plasma P concentrations at wk 4 and clinically important adverse events (AE) reported within the first 12 wks of treatment.

Methods: The % of patients with hypertension (defined as ≥ 15mmHg - baseline on 3 occasions)- a recognized PD marker for this class of agents- or other AEs (CTC grades), occurring during the first 12 wks of treatment were calculated by wk4 Cmin quartiles (Q1-Q4: median and range).

Results: P concentrations at 4 wks and AE data were available for 205 out of 225 pts. The incidence of hypertension was 58% in Q1, increasing with concentration to 78% at Q4. The incidence of diarrhea, hair color change, ALT increase, HFS (marked increase), and stomatitis were concentration-dependent, with ≥ 2 fold increase from Q1 to Q4. The incidence of nausea, fatigue, vomiting, dysgeusia, and rash were variable or displayed a flat relationship with Cmin.

Conclusions: The incidence of some AEs, such as diarrhea, ALT, HFS (marked relation), and stomatitis increased with plasma Cmin while others did not. We suggest that concentration-dependent AEs are more likely to respond to P dose reduction and as such, provides support for development of a dose optimization strategy.

[Table: see text]

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The impact of comorbidity on survival among men with localized prostate cancer

8

Background: To provide patients and clinicians more accurate estimates of co-morbidity specific survival stratified by patient age, tumor stage and tumor grade.

Methods: We conducted a ten year competing risk analysis of 19,639 men age 66 years and older identified by the Surveillance, Epidemiology and End Results (SEER) program linked to Medicare program files. All men were diagnosed with localized prostate cancer and received no surgery or radiation within 180 days of diagnosis. The analysis was stratified by tumor grade and stage and by age and co-morbidity at diagnosis classified using the Charlson co-morbidity index. Underlying causes of death were obtained from SEER.

Results: During the first ten years following diagnosis men with moderately and poorly differentiated prostate cancer were more likely to die from causes other than their disease. For men age 66-74 years with stage T1c Gleason score 5-7 disease at diagnosis, ten year overall mortality rates and prostate cancer specific rates were 28.8%, 50.5%, 83.1% and 4.8%, 2.0%, 5.3% respectively for men with Charlson scores 0, 1 and > 2. For men age 66-74 years with T1c Gleason score 8-10 disease at diagnosis, the corresponding rates were 55.0%, 52.0%, 64.3% and 25.7%, 20.2%, 13.7% respectively for men with Charlson scores 0, 1, > 2. Death from competing medical hazards was roughly comparable for men with stage T2 disease and higher for all men over age 75.

Conclusions: Patients and clinicians should consider using co-morbidity specific data to estimate the threat posed by localized prostate cancer.

No significant financial relationships to disclose.

Gastrointestinal toxicities following radiation therapy for localized prostate cancer

64

Background: Radiation therapy (RAD) is commonly employed to treat localized prostate cancer; however, representative data regarding treatment related toxicities compared to conservative management (CM) is sparse.

Methods: We performed a population-based cohort study, using Medicare claims data linked to the Surveillance, Epidemiology, and End Results data, to evaluate gastrointestinal (GI) toxicities in men aged 65-85 years treated with either primary RAD or CM for T1-T2 prostate cancer diagnosed in 1992-2005. In this study, only GI toxicities requiring interventional procedures occurring after 6 months of cancer diagnosis were included. Competing risk models were used with the following covariates: year of diagnosis, comorbidity, age, tumor stage, cancer grade, hormone use within 1 year of diagnosis, region, race, poverty and marital status.

Results: Among 41,859 patients in this study, 28,021 patients received radiation therapy, 19,287 with external beam radiation therapy (EBRT) alone, and 5,138 with brachytherapy alone. The most common GI toxicity was GI bleeding or ulceration. GI toxicity rates were 6.1% after 3D-conformal therapy (3D-CRT), 2.8% after intensity modulated radiation therapy (IMRT), 2.6% after brachytherapy, 8.2% after proton therapy and 1.1% for CM patients. In the multivariate models, RAD group was associated with a higher hazard of GI toxicities (hazard ratio [HR] 4.68; 95% CI, 3, 93-5.58) than CM. Comparing to 3D-CRT, brachytherapy (HR 0.62; 95% CI, 0.51-0.75) and IMRT (HR 0.67; 95% CI, 0.55-0.82) are associated with a lower hazard of GI toxicities, while proton therapy is associated with a higher hazard of GI toxicities (HR 2.15; 95% CI, 1.45-3.17).

Conclusions: Radiation therapy is associated with a higher risk of GI toxicities than CM. Among different modalities of radiation therapy, protons therapy is associated with the highest risk of GI toxicities, followed by 3D-CRT, IMRT, and brachytherapy. The increased GI toxicities for patients with proton therapy may reflect a learning curve in the early years.

No significant financial relationships to disclose.

Is radiation therapy superior to conservative management in men with localized prostate cancer?

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Background: Radiation therapy is commonly employed for localized prostate cancer; however, there is little data regarding the comparative effectiveness of radiation therapy (RAD) vs. conservative management (CM).

Methods: We performed a population-based cohort study, using Medicare claims data linked to the Surveillance, Epidemiology, and End Results data, to evaluate outcomes in 42,039 men aged 65-85 years treated with either primary RAD or CM for T1-T2 prostate cancer diagnosed in 1992-2005. To overcome potential biases associated with unmeasured confounding variables, we used instrumental variable analysis (IVA), a pseudo-randomization technique that captures the randomness associated with geographic variations in the use of RAD, to control for overt and hidden confounders.

Results: The majority of patients (57%) had low-risk disease (Gleason score ≤7, PSA <10, and T stage ≤T2a), and RAD was commonly used (60%) with considerable geographic variations. With median age 74 years and median follow-up 119 months, higher RAD use was not associated with improved survival in low-risk patients (10-year disease-specific survival differed by −0.9%, 94.9% vs. 95.8% in the highest and lowest tertile RAD use areas respectively; 95% C.I. −.1 to 0.6%). Among high-risk patients (Gleason score >7 or PSA >20), highest tertile RAD areas showed a borderline improved (2.7%) 10-year disease-survival (83.9% vs. 81.2% in the highest and lowest tertile radiation use areas; 95% C.I. −1.1% to 7.0%). The results in the moderate-risk group were between that of the low- and high-risk group. Primary RAD did not reduce future ADT use (odds ratios 0.95 for low-risk, 1.02 for moderate-risk, and 1.07 for high-risk with corresponding P values of 0.50, 0.86, and 0.51, respectively).

Conclusions: In patients aged over 65 years old with low-risk prostate cancer, primary RAD is unlikely to improve 10-year disease-specific survival or prevent future ADT use. Weighing the potential risks and benefits of radiation therapy is critical for decision making.

No significant financial relationships to disclose.

Plasma cytokine and angiogenic factors (CAFs) predictive of clinical benefit and prognosis in patients (Pts) with advanced or metastatic renal cell cancer (mRCC) treated in phase III trials of pazopanib (PAZO)

334

Background: PAZO is a multikinase inhibitor approved for the treatment of mRCC. From phase II study of PAZO in mRCC (VEG102616), plasma CAF analysis from 3 different platforms (cross platform correlation r >0.70) revealed several candidate CAFs including HGF, IL-6, IL-8, TIMP-1, VEGF, E-Selectin and OPN were found to be significantly correlated with clinical benefit (Tran ASCO 2010, #4522). To validate these findings, plasma were analyzed for CAFs from mRCC pts enrolled in phase III randomized, placebo controlled trial with PAZO where progression-free survival (PFS) of 9.2 months of PAZO and 4.2 months of placebo (hazard ratio:0.46 p<.0001) and overall response rate 30% was observed (Sternberg, JCO, 2010).

Methods: Plasma samples (n=344) from phase III randomized, placebo-controlled trial (VEG105192) were analyzed for candidate CAFs by a CLIA-certified laboratory (Aushon Biosystems, MA). These markers of PAZO and placebo arms were correlated with PFS by Cox regression and plotted in Kaplan Meier by using median concentration of each marker as a cutoff.

Results: Higher levels of IL-8 (p<0.006), HGF (p<0.01), OPN (p<0.001) and TIMP-1 (p<0.006) were associated with shorter PFS in PAZO treated pts. Higher levels of all these markers except HGF were also associated with shorter PFS in the placebo arm (IL-8 (p<0.002), OPN (p<0.001), IL-6 (<0.001), TIMP-1 borderline at p= 0.052) and were therefore prognostic. Only IL-6 was predictive of PFS benefit; pts with high IL-6 had a greater relative benefit from PAZO compared to placebo with a HR of 0.32 in the high IL-6 group and 0.57 in the low IL-6 group (p value for interaction 0.009).

Conclusions: This study validated HGF, IL-8, OPN, and TIMP-1 as markers associated with clinical benefit with PAZO treatment. IL-8 and OPN were confirmed as prognostic markers in the placebo arm and IL-6 was both a prognostic marker and predictive marker for pazopanib therapy.

[Table: see text]

In Situ, Real-Time Analysis of the Growth of Ferroelectric and Conductive Oxide Heterostructures by a New Time-of-Flight Pulsed Ion Beam Surface Analysis Technique

A new time-of-flight ion scattering and recoil spectroscopy (TOF-ISARS) technique has been developed and is now used to perform in situ, real-time analysis of ferroelectric and conductive oxide layers during growth. Initial results presented here show various major effects, namely: (a) RuO2 films on MgO substrates appear to be terminated in O atoms on the top layer located in between Ru atoms lying in the layer underneath (This effect may have major implications for the explanation of the elimination of polarization fatigue demonstrated for RuO2/PZT/RuO2 heterostructure capacitors); (b) deposition of a Ru monolayer on top of a Pb monolayer results in surface segregation of Pb until a complete Pb layer develops over the Ru monolayer; and (c) a Pb/Zr/Ti layered structure yields a top Pb layer with first evidence of the existence of Pb vacancies, which also may have major implications in relation to the electrical characteristics of PZT-based capacitors.

Environmental Effects on Subcritical Delamination of Dielectric and Metal Films from Organosilicate Glass (OSG) Thin Films

Subcritical delamination of dielectric and metal films from organosilicate glass (OSG) thin films was studied in controlled ambient with different levels of relative humidity and in aqueous environments of varying pH. The material systems studied include OSG/SiO2, OSG/TaN and OSG/SiNx. For both sets of experiments, subcritical crack growth in OSG is found to be described by a model originally developed for soda-lime silicate glass. The threshold energy release rate for water molecule-assisted cracking varies linearly with the natural logarithm of water partial pressure. In aqueous environments, the threshold value decreases linearly with increasing pH in accordance with a simple model. The slope of crack growth rate curve also decreases with increasing pH.

A multinational phase II study of liposome irinotecan (PEP02) for patients with gemcitabine-refractory metastatic pancreatic cancer

237

Background: PEP02 is a novel nanoparticle liposome formulation of irinotecan (CPT-11) that has improved pharmacokinetics and tumor biodistribution of both CPT-11 and its active metabolite-SN38 compared to the free form drug. PEP02 has showed encouraging safety and efficacy in various tumor types, including significant antitumor activity in a human pancreatic cancer L3.6pl orthotopic nude mouse xenograft model. In previous phase I studies, PEP02 either alone or in combination with 5-FU/LV demonstrated prolonged disease control in 5 of 7 (71%) patients (pts) with gemcitabine (GEM)-refractory advanced pancreatic cancer (PC). This phase II study aims to evaluate PEP02 monotherapy as 2nd-line treatment in pts with metastatic, GEM-refractory PC.

Methods: Pts were eligible if they had metastatic pancreatic adenocarcinoma, KPS ≥ 70, and progressed following one line of GEM-based therapy. Treatment consisted of PEP02 120 mg/m2 administered as a 90-minute infusion every 3 weeks. A Simon's 2-stage design was used with 16 pts in the first stage and 39 pts in total; primary objective was 3-month survival rate (OS3-month).

Results: Between March 2009 and August 2010, 37 pts were enrolled at 3 centers in the U.S. and Taiwan. Characteristics for the first 31 evaluable pts: 13 M/18 F; age 39-82 yrs; 19 Asian/12 Caucasian, KPS 100/90/80/70: 5/14/4/8. Mean number of treatment cycles is 5 (range, 1-22). Disease control rate (minor response + stable disease >2 cycles) is 52%. 8 of 24 pts (33%) with elevated baseline CA19-9 have had >50% biomarker decline. To date, 23/31 pts (74%) have survived > 3 months, with 4 pts still alive after 1 year. Reasons for study discontinuation: 74% progressive disease, 9% drug-related toxicity, 17% other. Preliminary safety data is available for the first stage. Most common G3/4 adverse events included: fatigue (31%), neutropenia (25%), nausea/vomiting (19%), and diarrhea (13%).

Conclusions: This study has already met its primary endpoint (predicted OS3-month >65%). PEP02 appears to have both activity and tolerable side effects for pts with metastatic, GEM-refractory PC, and represents a promising option for this pt population with few standard options.

[Table: see text]

Comparisons of clinical features of HLA-DRB1*07 positive and negative vitiligo patients in Chinese Han population

BACKGROUND

Human leucocyte antigen (HLA)-II alleles have been found to be associated with vitiligo in different populations, and several studies also suggested that HLA class II alleles/haplotypes were associated with a different type vitiligo. Of HLA class II alleles, DRB1*07 has consistently shown a positive association with vitiligo in Chinese Han population.

OBJECTIVE

To further explore the relationship between DRB1*07 and vitiligo and to evaluate the DRB1*07 effect on the clinical features of vitiligo in Chinese Han population.

METHODS

This study investigated DRB1*07 allele distribution in 1178 unrelated Chinese vitiligo patients and 1743 healthy controls using polymerase chain reaction/sequence specific primer method and observed clinical differences between DRB1*07 positive and DRB1*07 negative patients.

RESULTS

The analysis of the 1178 cases and 1743 controls revealed a highly association between DRB1*07 allele and vitiligo [odds ratio (OR) = 1.97, P = 2.13 × 10(-17) ]. DRB1*07 positive patients had early disease onset (OR = 1.49, P = 0.001), higher frequency of family history (OR = 1.44, P = 0.006) compared with DRB1*07 negative patients.

CONCLUSIONS

The DRB1*07 showed significant association with vitiligo in the study population. This study confirmed that DRB1*07 positive patients had some obvious clinical differences from DRB1*07 negative patients in the Chinese Han population.

Identifying Feasible Design Concepts for Products with Competing Performance Requirements by Metamodeling of Loss-Scaled Principal Components

Engineering design often involves the determination of design variable settings to optimize competing performance requirements. In the early design stages we propose narrowing down the domain of design solutions using metamodels of principal components of the multiple performance levels that have been scaled by a multivariate quadratic loss function. The multivariate quadratic loss function is often used as the objective function in reaching optimal solutions because it utilizes the correlation structure of the design's performance metrics and penalizes off-target performance in a symmetrical manner. We also compare the computational performance of these loss-scaled principal components when used to solve for the design with minimal expected multivariate quadratic loss under three modeling approaches: response surface methodology, multivariate adaptive regression splines, and spatial point modeling. We demonstrate the technique on the design of the mechanical frame of an electric vehicle with six desired performance levels determined simultaneously by the dimensions of eight mechanical design elements. The method is the focus in this work.

Abstract P5-13-06: Survival Benefit of Bisphophonates in Early Breast Cancer: A Meta-Analysis

Objectives: Bone is one of the most common metastatic sites of breast cancer. Recent date from randomized clinical studies suggested that the use of bisphophonates affect bone metastasis and survival in early breast cancer patients. Results from some of these trials are encouraging but somewhat contradictory. We conducted a meta analyses to assess the effect of bisphosphonates on bone metastasis and survival in primary breast cancer patients.

Methods: Trials were retrieved by searching the PubMed database, Cochrane Library and major cancer scientific conferences up to January 2010. All tirals randomized patients to receive any bisphosphonate versus non-use or placebo. Hazard ratios (HR) and its 95% CIs for bone metastasis free survival and overall survival were estimated.

Results: 8 eligible trials including 6132 patients entered the analysis. 3049 patients were treated with bisphosphonates and 3083 received either placebo or no treatment. Compared with no use, bisphophonates in the adjuvant setting improved the overall survival (HR=0.808; 95%CI 0.708-0.923; P = 0.022). However, the reduction of bone metastasis was failure to be seen (HR = 1.011; 95% CI 0.996-1.027; P = 0.667). Conclusion: Our meta-analysis provides additional evidence that adjuvant breast cancer treastment with bisphosphonates brought a survival benefit. However, the result should be carefully interpreted for that the statistical significance was not consistent in the bone benefit. Results of new clinical trials were awaited.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-13-06.

Bioengineered periodontal tissue formed on titanium dental implants

The ability to use autologous dental progenitor cells (DPCs) to form organized periodontal tissues on titanium implants would be a significant improvement over current implant therapies. Based on prior experimental results, we hypothesized that rat periodontal ligament (PDL)-derived DPCs can be used to bioengineer PDL tissues on titanium implants in a novel, in vivo rat maxillary molar implant model. Analyses of recovered implants revealed organized PDL tissues surrounding titanium implant surfaces in PDL-cell-seeded, and not in unseeded control, implants. Rat PDL DPCs also exhibited differentiative potential characteristic of stem cells. These proof-of-principle findings suggest that PDL DPCs can organize periodontal tissues in the jaw, at the site of previously lost teeth, indicating that this method holds potential as an alternative approach to osseointegrated dental implants. Further refinement of this approach will facilitate the development of clinically relevant methods for autologous PDL regeneration on titanium implants in humans.

Perinatal predictors of outcome in gastroschisis

OBJECTIVE

To identify perinatal risk variables predictive of outcome in gastroschisis.

STUDY DESIGN

Gastroschisis cases were collected over a 3-year period from a national database. Risk variables evaluated included gestational age (GA), birth weight, time of birth, admission illness severity (score for neonatal acute physiology-II, SNAP-II) score, and abdominal closure type. Mortality and survival outcomes were analyzed. Multivariate analyses were performed.

RESULT

In all, 239 infants were survived (96%). SNAP-II score predicted mortality (relative risk (RR)=1.07, 95% confidence interval (CI)=1.0 to 1.1). Length of hospital stay (LOS) and ventilation days were predicted by GA and by SNAP-II score. SNAP-II score predicted total parenteral nutrition (TPN) days (P=0.006). Severe cholestasis (conjugated bilirubin of >10 mg per 100 ml) was inversely related to GA (RR=0.77, 95% CI=0.61 to 0.97) and directly to categorical SNAP-II score (RR=3.4, 95% CI=1.2 to 10.1). Urgent closure predicted fewer TPN days (P=0.003) and shorter LOS (P=0.0002).

CONCLUSION

SNAP-II scores significantly predict mortality and survival outcomes. Urgent closure favors fewer TPN days and shorter LOS. Our data refute routine preterm delivery in gastroschisis.