MicroRNA-885-3p inhibits the growth of HT-29 colon cancer cell xenografts by disrupting angiogenesis via targeting BMPR1A and blocking BMP/Smad/Id1 signaling

The previous studies in this lab discovered that microRNA-885-3p (miR-885-3p) was regulated by a sulfated polysaccharide that bound to bone morphogenetic protein receptor, type IA (BMPR1A) to inhibit angiogenesis. However, its specific role and its mechanism of action in tumor cells have not been elucidated. We show that miR-885-3p markedly suppresses angiogenesis in vitro and in vivo. MiR-885-3p inhibits Smad1/5/8 phosphorylation and downregulates DNA-binding protein inhibitor ID-1 (Id1), a proangiogenic factor, by targeting BMPR1A, leading to impaired angiogenesis. Overexpression or silencing of BMPR1A affects angiogenesis in a Smad/Id1-dependent manner. We further show that miR-885-3p impairs the growth of HT-29 colon cancer cell xenografts in nude mice by suppressing angiogenesis through disruption of BMPR1A and Smad/Id1 signaling. These results support a novel role for miR-885-3p in tumor angiogenesis by targeting BMPR1A, which regulates a proangiogenic factor, and provide new evidence that targeting miRNAs might be an effective therapeutic strategy for improving colon cancer treatment.

Single-photon property characterization of 1.3 μm emissions from InAs/GaAs quantum dots using silicon avalanche photodiodes

We developed a new approach to test the single-photon emissions of semiconductor quantum dots (QDs) in the optical communication band. A diamond-anvil cell pressure device was used for blue-shifting the 1.3 μm emissions of InAs/GaAs QDs to 0.9 μm for detection by silicon avalanche photodiodes. The obtained g⁽²⁾(0) values from the second-order autocorrelation function measurements of several QD emissions at 6.58 GPa were less than 0.3, indicating that this approach provides a convenient and efficient method of characterizing 1.3 μm single-photon source based on semiconductor materials.

Randomised, double-blind trial of carboplatin and paclitaxel with daily oral cediranib or placebo in patients with advanced non-small cell lung cancer: NCIC Clinical Trials Group study BR29

INTRODUCTION

This randomised double-blind placebo-controlled study evaluated the addition of cediranib, an inhibitor of vascular endothelial growth factor receptors 1-3, to standard carboplatin/paclitaxel chemotherapy in advanced non-small cell lung cancer.

METHODS

Eligible patients received paclitaxel (200mg/m(2)) and carboplatin (area under the concentration time curve 6) intravenously every 3 weeks. Daily oral cediranib/placebo 20mg was commenced day 1 of cycle 1 and continued as monotherapy after completion of 4-6 cycles of chemotherapy. The primary end-point of the study was overall survival (OS). The trial would continue to full accrual if an interim analysis (IA) for progression-free survival (PFS), performed after 170 events of progression or death in the first 260 randomised patients, revealed a hazard ratio (HR) for PFS of ⩽ 0.70.

RESULTS

The trial was halted for futility at the IA (HR for PFS 0.89, 95% confidence interval [CI] 0.66-1.20, p = 0.45). A final analysis was performed on all 306 enrolled patients. The addition of cediranib increased response rate ([RR] 52% versus 34%, p = 0.001) but did not significantly improve PFS (HR 0.91, 95% CI 0.71-1.18, p = 0.49) or OS (HR 0.94, 95% CI 0.69-1.30, p=0.72). Cediranib patients had more grade 3 hypertension, diarrhoea and anorexia.

CONCLUSIONS

The addition of cediranib 20mg daily to carboplatin/paclitaxel chemotherapy increased RR and toxicity, but not survival.

Diagnosis and management of primary umbilical melanoma with omphalitis features

We report on a 62-year-old Chinese male patient who presented with a pigmented lesion in the umbilical area and who was treated for omphalitis in a local hospital for 1 month. Biopsy pathological examination revealed that the lesion was a melanoma. The Breslow depth was estimated at 3 mm, and Clark's level was IV. Ultrasonography showed no suspicious pathological lymph nodes, and no metastases were detected in the lung, liver or brain through CT scans. Reexcision was performed with lateral marginsd >2 cm from the original scar down to the peritoneum, including the umbilicus, round ligament of the liver and urachus. No adjuvant therapy was suggested, and the patient was still alive without recurrences or metastases after 36 months.

Record performance of electrical injection sub-wavelength metallic-cavity semiconductor lasers at room temperature

We demonstrate a continuous wave (CW) sub-wavelength metallic-cavity semiconductor laser with electrical injection at room temperature (RT). Our metal-cavity laser with a cavity volume of 0.67λ3 (λ = 1591 nm) shows a linewidth of 0.5 nm at RT, which corresponds to a Q-value of 3182 compared to 235 of the cavity Q, the highest Q under lasing condition for RT CW operation of any sub-wavelength metallic-cavity laser. Such record performance provides convincing evidences of the feasibility of RT CW sub-wavelength metallic-cavity lasers, thus opening a wide range of practical possibilities of novel nanophotonic devices based on metal-semiconductor structures.

Innovative estimation of survival using log-normal survival modelling on ACCENT database

Background:

The ACCENT database, with individual patient data for 20 898 patients from 18 colon cancer clinical trials, was used to support Food and Drug Administration (FDA) approval of 3-year disease-free survival as a surrogate for 5-year overall survival. We hypothesised substantive differences in survival estimation with log-normal modelling rather than standard Kaplan–Meier or Cox approaches.

Methods:

Time to relapse, disease-free survival, and overall survival were estimated using Kaplan–Meier, Cox, and log-normal approaches for male subjects aged 60–65 years, with stage III colon cancer, treated with 5-fluorouracil-based chemotherapy regimens (with 5FU), or with surgery alone (without 5FU).

Results:

Absolute differences between Cox and log-normal estimates with (without) 5FU varied by end point. The log-normal model had 5.8 (6.3)% higher estimated 3-year time to relapse than the Cox model; 4.8 (5.1)% higher 3-year disease-free survival; and 3.2 (2.2)% higher 5-year overall survival. Model checking indicated greater data support for the log-normal than the Cox model, with Cox and Kaplan–Meier estimates being more similar. All three model types indicate consistent evidence of treatment benefit on both 3-year disease-free survival and 5-year overall survival; patients allocated to 5FU had 5.0–6.7% higher 3-year disease-free survival and 5.3–6.8% higher 5-year overall survival.

Conclusion:

Substantive absolute differences between estimates of 3-year disease-free survival and 5-year overall survival with log-normal and Cox models were large enough to be clinically relevant, and warrant further consideration.

From cirrhosis to hepatocellular carcinoma in HCV-infected patients: genes involved in tumor progression

BACKGROUND

Hepatocellular carcinoma (HCC) is an aggressive tumor with poor prognosis. Understanding molecular changes in hepatocellular carcinoma should improve identification of risk factors in molecular subtypes and provide potential targets for early detection and therapy.

AIM

The present study aimed to analyze the molecular mechanism of the transition from hepatitis C virus (HCV) induced cirrhosis to HCV induced HCC using microarray analysis combined with bioinformatics techniques. METHODS, To accomplish this, we performed the differential coexpression analysis of hepatic gene expression in samples of HCV-cirrhotic patients with and without HCC. Total 465 genes were identified and some of them were used to construct a regulatory network.

RESULTS

Our analysis indicated that several differentially co-express genes might play crucial roles in HCC development, including NA3C2, AHR, MYC, FOXO1 and FOSB. Further analysis predicted these genes might be involved in HCC through pathways of "ribosome", "steroid biosynthesis", "spliceosome" and so on. Moreover, these genes may serve as potential therapeutic targets for the treatment of HCC.

CONCLUSIONS

In conclusion, our findings confirm the presence of multiple molecular alterations during HCV-infected HCC hepatocarcinogenesis and indicate the possibility for identifying prognostic factors associated with HCC progression.

SU-D-BRB-05: Small Animal Lung Compliance Imaging: Assessment System for Tissue Sensitivity to Radiation Induced Lung Injury

PURPOSE

Recent clinical trials and animal studies have indicated that the tissue sensitivity to radiation induced lung injury (RILI) may be region- specific. In this study, we propose a new 4D cone beam CT (CBCT) basedcompliance imaging method to measure regional pulmonary function change in precisely irradiated small animal under CBCT guidance on small animal radiation research platform (SARRP) to facilitate our understanding of region-specific tissue sensitivity to RILI.

METHODS

Four Sprague-Dawley rats underwent prospective pressure gated 4D CBCT on SARRP. Three animals were selected as control group which underwent a second 4D CBCT scan. The fourth animal was irradiated in the central lung (24 Gy) using 3 × 3 mm collimating cone 2 months prior to the scan. The specific compliance (Csp) was calculated via the real time pressure measurement from the ventilator and displacement field from 3D B-spline image registration between the end of inhale and end of exhale phases from the 4D CBCT scan. The 3D Csp maps from the control animal group were mapped to the irradiated animal as a Csp functional atlas for statistical analysis. We alsoevaluated the repeatability of the Csp measurement on a voxel-by-voxel basis.

RESULTS

No significant Csp difference is found after two month of radiation between the irradiated rat (0.22±0.05) and the functional atlas (0.21±0.07). The observation is consistent with previous publications. The averaged linear correlation coefficient between the voxel-by-voxel Csp measurements from initial and repeat scans in control group is 0.98.

CONCLUSIONS

We proposed a method that uses 4D CBCT based compliance imaging to measure region-specific tissue sensitivity of RILI. We compared the irradiated animal two months after radiation with the control group. Our study shows an excellent robustness of the proposed method for regional lung tissue specific compliance measurement. This work was supported in part by UVa George Amorino Pilot Grant.

SU-E-J-192: Static Breath-Hold MRI Based Measurement of Change in Pulmonary Function Following a Course of Radiation Therapy

PURPOSE

Radiation Therapy (RT) induced pulmonary function change may depend on the location, underlying function of that lung prior to radiations, radiation dose/fractionation and other factors. We propose to evaluate the radiation induced pulmonary function change using static breath-hold MRI scans with vascular information and 3D deformable image registration which can provide pulmonary function relative to RT dose on a regional basis.

METHODS

A MRI scan pair near the end of inhale and near the end of exhale with breath hold were acquired for one lung cancer patient before RT and 6 months after RT. The patient was treated with SBRT with 55 Gy to PTVs in the right and the left lung respectively. B-spline based vesselness preserving image registration algorithm was applied to register the MRI pair for the calculation of local lung expansion as a measurement of regional pulmonary function (PF). The PF maps before RT and after RT were then mapped to the planning CT using the same algorithm tuned for MRI-CT registration. The pulmonary function change was calculated via the PF ratio between two MRI pairs.

RESULTS

Strong spatial correlation was found between the irradiated lung region and the region with greatly decreased PF. Based on dose and PFC distribution, no strong determinant factor was found for PF lost in the left lung while the right lung shows that all the lung tissue receiving dose larger than 28 Gy will have a decreased PF.

CONCLUSIONS

We demonstrated a method that uses static breath-hold MRI based lung imaging to evaluate radiation induced pulmonary function change which can be applied to study the dose and the pulmonary function change in a regional basis. This work is supported by NIH grant support 1R21CA144063.

SU-E-T-26: Evaluation of New Pre-Treatment In-Air Patient Specific QA Software for TomoTherapy Treatments

PURPOSE

Math Resolutions, LLC, has extended their Dosimetry Check quality assurance software to include TomoTherapy treatments. Data collected from TomoTherapy's MVCT detectors is processed and compared to the planned treatment dose allowing for pre-treatment QA without the use of phantoms and other detectors. This study presents an overview of our experience at the University of Virginia developing, implementing, and verifying this novel QA strategy.

METHODS

Low modulation and high modulation cheese phantom plans as well as patient plans (prostate, GYN, and vertebra) were used to test the Dosimetry Check in-air software. For all evaluations the treatment table was removed from the XML file of each plan using software provided by Accuray and the resulting in-air calibration plan was delivered. The exit detector sinogram was extracted from the machine and imported into Dosimetry Check along with the TomoTherapy calculated planned dose. The fluence maps were reconstructed and used to recalculate the dose.

RESULTS

The percent difference between the planned dose and the dose calculated from the exit detectors by Dosimetry Check ranged between 0.62% for a simple low modulation cheese phantom plan with a cylindrical target to 7.3% for a high modulation 2.5cm prostate plan. The gamma indices reported range from 94.7% to 97.8% <1 over the overall calculation area for the plans tested using a gamma of 3% and 3mm. For the area receiving over 80% of the prescribed dose, the gamma ranged from 80.7% to 92.9% <1.

CONCLUSIONS

The results of our investigation of Math Resolutions' new product in development, Dosimetry Check's pre-treatment in-air QA software, demonstrate that it has the potential be a very useful and practical tool for TomoTherapy QA. Further testing is being performed in which various errors are intentionally introduced in the delivered dose to test the limits of Dosimetry Check's sensitivity. Research Grant from Math Resolutions LLC 01/12/2012-01/11/2013 Math Resolutions’ Dosimetry Check software was given to UVa to assist with evaluating the precision of the product in reconstructing dose from the TomoTherapy exit detector data.

SU-E-J-82: Improvement in Reproducibility of Lung Expansion Measures with Respiratory Effort Correction

PURPOSE

Longitudinal measurements of pulmonary function must account for subject variation when assessing radiation-induced changes. Previously, we reported intra-subject reproducibility of Jacobian-based measures of lung tissue expansion using repeat 4DCT scans prior to radiation therapy without correcting for differences in respiratory effort. In this study, we present two normalization schemes that correct ventilation images for variations in respiratory effort.

METHODS

Two repeat 4DCT image acquisitions were collected before treatment from seven patients. Using a tissue volume preserving deformable image registration algorithm, two Jacobian ventilation maps were computed from separate acquisitions. Two effort normalization strategies were investigated using intermediated inspiration phases upon the principles of equivalent tidal volume (ETV) and equivalent lung volume (ELV). Additional experiments were performed to verify the effectiveness of the ETV method. Scatter plots of two ventilation maps and statistical parameters of Jacobian ratio were compared before and after each effort correction approach.

RESULTS

The scatter plots of the ventilation maps show improvement in measurement reproducibility using either the ETV or ELV effort correction for all but one case. The one case that did not show improvement had a very similar lung volumes and tidal volumes in the two studies, so effort correction was unnecessary. The coefficient of variation (CV) of Jacobian ratio improved by 21±11 percent (mean±standard deviation) after ETV, and improved by 20±17 percent after ELV. Our experimental results on ETV show the decrease of tidal volume difference in two acquisitions improves reproducibility of lung expansion measures.

CONCLUSIONS

ETV and ELV correction methods improve the reproducibility of pulmonary function measurements in subjects that have differences in respiratory effort in the baseline and followup scans. Additional work is needed to investigate whether ETV or ELV is more effective, and to develop alternate regional normalization schemes that can account for difference in lung expansion rates.

A phase III randomized trial comparing intermittent versus continuous androgen suppression for patients with PSA progression after radical therapy: NCIC CTG PR.7/SWOG JPR.7/CTSU JPR.7/UK Intercontinental Trial CRUKE/01/013

3

Background: In men with PSA recurrence after radical radiotherapy (RRT), intermittent androgen suppression (IAS) has been suggested by phase II trials to improve quality of life (QoL) but effects on survival are unknown. In this Intergroup randomized phase III trial, we compared IAS vs continuous androgen deprivation (CAD) to test for non-inferiority of IAS with respect to overall survival (OS).

Methods: Eligible men had rising PSA > 3.0 ng/ml >1 year post RRT, either initial or salvage, for localized prostate cancer. Patients could receive up to 1 year of neo/adjuvant androgen deprivation therapy (ADT) completed >1 year prior. Stratification factors were time since RRT (>1-3 vs >3 years), initial PSA (<15 vs >15), prior radical prostatectomy and prior ADT. IAS was delivered for 8 months in each cycle with restart when PSA reached >10 ng/ml off treatment. Primary endpoint was OS; secondary endpoints included time to hormone refractory state (HR), QoL, cholesterol/HDL/LDL, duration of treatment/non-treatment intervals, time to testosterone and potency recovery. The independent DSMC recommended halting the trial after a planned interim analysis demonstrated that a pre-specified stopping boundary for non-inferiority was crossed.

Results: 1,386 patients were randomized to IAS (690) or CAD (696) arms. Arms were balanced for important baseline factors. Median follow up was 6.9 years. IAS patients completed a median of 2 x 8 month cycles (range: 1-9). 524 deaths were observed (268 on IAS vs 256 on CAD). Median OS was 8.8 vs 9.1 years on IAS and CAD arms, respectively (HR 1.02, 95%CI 0.86-1.21; p for non-inferiority [HR IAS vs CAD ≥ 1.25] = 0.009). The IAS arm had more disease related (122 vs 97) and fewer unrelated (134 vs 146) deaths. Time to HR was statistically significantly improved on the IAS arm (HR 0.80, 95%CI 0.67-0.98; p = 0.024). IAS patients had reduced hot flashes, but otherwise there was no evidence of differences in AEs, including myocardial events or osteoporotic fractures.

Conclusions: In men with PSA recurrence after RRT IAS, given as described herein, is non-inferior to CAD with respect to OS.

No significant financial relationships to disclose.

Bacterial community dynamics in two full-scale wastewater treatment systems with functional stability

AIMS

To characterize the bacterial community dynamics over 1 year in two full-scale wastewater treatment systems operated under constant conditions and exhibiting stable performance.

METHODS AND RESULTS

Functional stability was defined and quantified by the effluent concentration of biological oxygen demand, total nitrogen and ammonia. Community dynamics were investigated using specific PCR followed by terminal restriction fragment length polymorphism (T-RFLP) of the 16S rRNA gene. The T-RFLP results indicated that during the period of functional stability, the bacterial community structures in two full-scale wastewater treatment systems were not stable, and the average change rates every 15 days of the two systems were 22.6 ± 6.9 and 21.6 ± 7.3%, respectively. The corresponding species with dominant T-RFs were determined by clonal sequencing and T-RFLP. Based on Pareto-Lorenz distribution curves, it was observed that only a small number of micro-organisms were numerically dominant in the two systems.

CONCLUSIONS

The results of this study showed that, throughout the period of the study, the bacterial community structure changed significantly in two full-scale wastewater treatment systems despite the stable function.

SIGNIFICANCE AND IMPACT OF THE STUDY

The findings enrich the theory involving the relation between bacterial community dynamics and functional stability in full-scale wastewater treatment plants.

Lovastatin inhibits EGFR dimerization and AKT activation in squamous cell carcinoma cells: potential regulation by targeting rho proteins

We recently showed the ability of lovastatin to inhibit the function of the epidermal growth factor receptor (EGFR) and its downstream signaling of the phosphatidylinositol-3 kinase/AKT pathway. Combining lovastatin with gefitinib, a potent EGFR inhibitor, induced synergistic cytotoxicity in various tumor-derived cell lines. In this study, lovastatin treatment was found to inhibit ligand-induced EGFR dimerization in squamous cell carcinoma cells and its activation of AKT and its downstream targets 4E-binding protein 1 and S6 kinase 1. This inhibition was associated with global protein translational inhibition shown by a decrease in RNA associated polysome fractions. The effects of lovastatin on EGFR function were reversed by the addition of geranylgeranyl pyrophosphate, which functions as a protein membrane anchor. Lovastatin treatment induced actin cytoskeletal disorganization and the expression of geranylgeranylated rho family proteins that regulate the actin cytoskeleton, including rhoA. Lovastatin-induced rhoA was inactive as EGF stimulation failed to activate rhoA and inhibition of the rho-associated kinase, a target and mediator of rhoA function, with Y-27632 also showed inhibitory effects on EGFR dimerization. The ability of lovastatin to inhibit EGFR dimerization is a novel exploitable mechanism regulating this therapeutically relevant target. To explore the potential clinical significance of this combination, we evaluated the effect of statin on the overall survival (OS) and disease-specific survival (DSS) of patients with advanced non-small-cell lung cancer enrolled in the NCIC Clinical Trials Group phase III clinical trials BR21 (EGFR tyrosine kinase inhibitor erlotinib versus placebo) and BR18 (carboplatin and paclitaxel with or without the metalloproteinase inhibitor BMS275291). In BR18, use of statin did not affect OS or DSS. In BR21, patients showed a trend for improvement in OS (HR: 0.69, P=0.098) and DSS (HR: 0.62, P=0.048), but there was no statin x treatment interaction effect (P=0.34 and P=0.51 for OS and DSS, respectively).