Development and external validation of a machine learning model for prediction of survival in undifferentiated pleomorphic sarcoma

PURPOSE

Machine learning (ML) algorithms to predict cancer survival have recently been reported for a number of sarcoma subtypes, but none have investigated undifferentiated pleomorphic sarcoma (UPS). ML is a powerful tool that has the potential to better prognosticate UPS.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried for cases of histologically confirmed undifferentiated pleomorphic sarcoma (UPS) (n = 665). Patient, tumor, and treatment characteristics were recorded, and ML models were developed to predict 1-, 3-, and 5-year survival. The best performing ML model was externally validated using an institutional cohort of UPS patients (n = 151).

RESULTS

All ML models performed best at the 1-year time point and worst at the 5-year time point. On internal validation within the SEER cohort, the best models had c-statistics of 0.67-0.69 at the 5-year time point. The Multi-Layer Perceptron Neural Network (MLP) model was the best performing model and used for external validation. Similarly, the MLP model performed best at 1-year and worst at 5-year on external validation with c-statistics of 0.85 and 0.81, respectively. The MLP model was well calibrated on external validation. The MLP model has been made publicly available at https://rachar.shinyapps.io/ups_app/ .

CONCLUSION

Machine learning models perform well for survival prediction in UPS, though this sarcoma subtype may be more difficult to prognosticate than other subtypes. Future studies are needed to further validate the machine learning approach for UPS prognostication.

Selective optogenetic stimulation of glutamatergic, but not GABAergic, vestibular nuclei neurons induces immediate and reversible postural imbalance in mice

Glutamatergic and GABAergic neurons represent the neural components of the medial vestibular nuclei. We assessed the functional role of glutamatergic and GABAergic neuronal pathways arising from the vestibular nuclei (VN) in the maintenance of gait and balance by optogenetically stimulating the VN in VGluT2-cre and GAD2-cre mice. We demonstrate that glutamatergic, but not GABAergic VN neuronal subpopulation is responsible for immediate and strong posturo-locomotor deficits, comparable to unilateral vestibular deafferentation models. During optogenetic stimulation, the support surface dramatically increased in VN^VGluT2+ mice, and rapidly fell back to baseline after stimulation, whilst it remained unchanged during similar stimulation of VN^GAD2+ mice. This effect persisted when vestibular tactilo kinesthesic plantar inputs were removed. Posturo-locomotor alterations evoked in VN^VGluT2+ animals were still present immediately after stimulation, while they disappeared 1 h later. Overall, these results indicate a fundamental role for VN^VGluT2+ neurons in balance and posturo-locomotor functions, but not for VN^GAD2+ neurons, in this specific context. This new optogenetic approach will be useful to characterize the role of the different VN neuronal populations involved in vestibular physiology and pathophysiology.

Mobilization of recalcitrant phosphorous and enhancement of pepper P uptake and yield by a new biocontrol and bioremediation bacterium Burkholderia cepacia CQ18

AIMS

Phosphorus (P) is a finite resource and inoculation of phosphorus-mobilizing bacteria (PMB) is a promising approach for the enhancement of soil P availability and plant P uptake. This drives scientists to search for the microbes effective in mobilizing legacy P in soils.

METHODS AND RESULTS

The current incubation and greenhouse pot experiments were conducted to investigate P mobilization and pepper P uptake as affected by a new biocontrol and bioremediation bacterium Burkholderia cepacia CQ18. This bacterium converted Ca₃ (PO₄ )₂ , FePO₄ , AlPO₄ , and lecithin into soluble inorganic P in the culture solutions and increased available P (including water-soluble P and Olsen P) in the soil. There were positive correlations between the soluble inorganic phosphorus and the exudates (protons, organic acids (oxalate and gluconate), siderophores and phosphatases) in culture solutions. Pepper plant biomass, fruit yield and P uptake changed in the sequence: chemical fertilizers plus bacterial inoculant >only chemical fertilizers >only bacterial inoculant >blank control.

CONCLUSIONS

Taking into account the wide spectrums of P mobilization and simultaneous production of acid, neutral and alkaline phosphatases at a given pH, B.cepacia CQ18 may be a potential PMB used in soils with wide pH ranges. The mechanisms employed by this bacterium in the solubilization of recalcitrant inorganic P could be the efflux of protons, organic acids (oxalate and gluconate) and siderophores. Phosphatases could be of utmost importance in the mineralization of the organic P. The production of siderophores and phosphatases by of B.cepacia CQ18 could thus be crucial for not only the antagonism against plant pathogens but also the mobilization of soil sparingly available P.

SIGNIFICANCE AND IMPACT OF THE STUDY

Burkholderia cepacia CQ18 could be potentially developed into a biofertilizer.

Contribution of single-gene defects to congenital cardiac left-sided lesions in the prenatal setting

OBJECTIVES

To explore the contribution of single-gene defects to the genetic cause of cardiac left-sided lesions (LSLs), and to evaluate the incremental diagnostic yield of whole-exome sequencing (WES) for single-gene defects in fetuses with LSLs without aneuploidy or a pathogenic copy-number variant (pCNV).

METHODS

Between 10 April 2015 and 30 October 2018, we recruited 80 pregnant women diagnosed with a LSL who had termination of pregnancy and genetic testing. Eligible LSLs were aortic valve atresia or stenosis, coarctation of the aorta, mitral atresia or stenosis and hypoplastic left heart syndrome (HLHS). CNV sequencing (CNV-seq) and WES were performed sequentially on specimens from these fetuses and their parents. CNV-seq was used to identify aneuploidies and pCNVs, while WES was used to identify diagnostic genetic variants in cases without aneuploidy or pCNV.

RESULTS

Of 80 pregnancies included in the study, 27 (33.8%) had a genetic diagnosis. CNV-seq analysis identified six (7.5%) fetuses with aneuploidy and eight (10.0%) with pCNVs. WES analysis of the remaining 66 cases revealed diagnostic genetic variants in 13 (19.7%) cases, indicating that the diagnostic yield of WES for the entire cohort was 16.3% (13/80). KMT2D was the most frequently mutated gene (7/66 (10.6%)) in fetuses with LSL without aneuploidy or pCNVs, followed by NOTCH1 (4/66 (6.1%)). HLHS was the most prevalent cardiac phenotype (4/7) in cases with a KMT2D mutation in this cohort. An additional six (9.1%) cases were found to have potentially deleterious variants in candidate genes.

CONCLUSIONS

Single-gene defects contribute substantially to the genetic etiology of fetal LSLs. KMT2D mutations accounted for approximately 10% of LSLs in our fetal cohort. WES has the potential to provide genetic diagnoses in fetuses with LSLs without aneuploidy or pCNVs. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

[Risk factors of anastomotic leakage after robotic surgery for low and mid rectal cancer]

Objective: To investigate the risk factors associated with anastomotic leakage after robotic surgery in mid-low rectal cancer. Methods: A retrospective case-control study method was conducted. Inclusion criteria: (1) 18 to 80 years old; (2) pathologically confirmed rectal cancer; (3) distance <10 cm from tumor to anal margin; (4) robotic anterior rectal resection. Patients with previous history of colorectal cancer surgery, distant metastases or other malignant tumors, undergoing emergency surgery, with severe abdominal adhesions or those receiving combined organ resection were excluded. Based on the above criteria, 636 patients undergoing robotic radical sphincter-preserving surgery for mid-low rectal cancer in Zhongshan Hospital from January 2015 to December 2018 were included in this study, including 398 males (62.6%) and 238 females (37.4%) with a mean age of (61.9±11.3) years. Sixty-eight cases (10.7%) received neoadjuvant chemoradiotherapy. Amony the 636 included patients, 123(19.3%) underwent natural orifice specimen extraction surgery (NOSES) and 15 (2.3%) underwent preventive stoma. According to the cirteria developed by the International Rectal Cancer Research Group in 2010, the anastomotic leakage was classified as grade A (no requirement of intervention), B (requirement of intervention), and C (requirement of operation). Logistic regression was used to analyze the relationship between anastomotic leakage and clinicopathological factors. Factors in univariate analysis with P<0.05 were included in the multivariate analysis. Results: Anastomotic leakage occurred in 38 cases (6.0%). The grading of anastomotic leakage was grade A in 13 cases (2.0%), grade B in 19 cases (3.0%), and grade C in 6 cases (0.9%). The 3-year disease-free survival rate of patients with anastomotic leakage and without anastomotic leakage was 83.5% and 83.6% respectively (P=0.862); the 3-year overall survival rate of the two group was 85.1% and 87.5% respectively (P=0.296). The results of univariate logistic regression analysis showed that male (P=0.011), longer operation time (P=0.042), distance ≤5 cm from tumor to anal margin (P=0.012), more intraoperative blood loss (P=0.048) were associated with anastomotic leakage (all P<0.05). NOSES was not associated with anastomotic leakage (P=0.704). Multivariate analysis confirmed that male (OR=3.03, 95%CI: 1.37 to 7.14, P=0.010), operation time ≥180 minutes (OR=2.04, 95%CI: 1.03 to 3.99, P=0.040), distance ≤5 cm from tumor to anal margin (OR=2.56, 95%CI:1.28 to 5.26, P=0.008) were independent risk factors for anastomotic leakage. Conclusion: Male, short distance from tumor to anal margin, and long operation time are independent risk factors for anastomotic leakage in patients undergoing robotic mid-low rectal cancer radical surgeries. These patients need to be cautiously treated during surgery.

Effects of quorum quenching on temporal succession of activated sludge microbial community in a membrane bioreactor

AIMS

Quorum quenching (QQ) is an attractive strategy for mitigating biofouling in membrane bioreactors (MBRs). However, the effects of QQ on the activated sludge (AS) process have not been adequately evaluated. This study investigated the long-term effects of QQ on a laboratory-scale anoxic-oxic MBR, focusing on AS performance and microbial community.

METHODS AND RESULTS

Anoxic-oxic MBRs with and without QQ were operated for 91 days. QQ did not affect COD and TN removal efficiencies over the experimental period, during which its activity remained >90%. QQ reduced floc size by approximately 8% but had no effect on biomass concentration. AS microbial communities were regularly analysed using massively parallel sequencing. AS bacterial communities were temporally dynamic irrespective of QQ presence, for example, a temporal increase in bacterial diversity and a temporal decay of community similarity. QQ counteracted the temporal change in diversity and the temporal distance-community decay. Community comparison revealed that QQ changed the successional trajectory of the AS community at a late period, because it decelerated temporal changes of specific members, such as Thiothrix and Sphingomonadaceae*. Correlation networks revealed that QQ increased network clustering, complexity and density. The combined results suggest that the tighter microbial association by QQ increased the community resistance.

CONCLUSIONS

QQ can enhance the diversity and stability of the AS community in MBR by counteracting the innate temporal change in community structure.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our findings are useful for the further advancement of QQ-based strategies in engineered microbial environments.

P4649Whole exome sequencing and whole genome sequencing improves genetic diagnosis of fetals with heterotaxy syndrome revealed by prenatal ultrasound

Background

Heterotaxy (Htx) syndrome is an congenital disorders resulting from incorrectly establishment of left-right patterning during embryogenesis. Over 96% of patients with Htx exhibit some form of congenital heart disease (CHD),and has relatively poor survival. Multiple lines of evidence support genetic contributions to the etiology of Htx. As a specific genetic etiology is currently identifiable in only a minority of patients, there remains enormous potential for novel gene and pathway discovery.

Purpose

The aim of this study was to investigate the diagnostic yield of whole-exome sequencing (WES) and whole-genome sequencing (WGS) in fetuses with the pathogenesis of Htx, to explore candidate genes for Htx and to expand the clinical phenotype of known genetic conditions.

Method

WES and WGS were performed on specimens from 46 fetuses diagnosed with Htx and their parents. The single-nucleotide variants (SNVs) and copy-number variants (CNVs) were filtered and annotated by standard analysis process. All reported variants were classified according to he American College of Medical Genetics and Genomics guidelines.

Results

In the 46 fetuses, the detection rates of pathogenic and likely pathogenic variations were21.7% (10/46) and 10.9% (5/46) respectively. Ten pathogenic variations were identified on genes of CCDC114, DNAH11, ARMC4, STRA6, PQBP1 (hemizygote), HYDIN, RAI1 (Alagille Syndrome), ZFMP2 and Del(22q11.2) Syndrome. Five likely pathogenic variation were on DNAAF1 (Holshner syndrome), NF1, NEXN, NOTCH3 and FOXC1. Of 30 fetuses with prenatally diagnosed right atrial isomerism (RAI), the main intracardiac anomalies were atrioventricular canal (AV canal), isomerism of right atrial appendages, pulmonary stenosis or atresia (PS & PA) and right aortic arch. In 16 fetuses diagnosed left atrial isomerism (LAI) the main intracardiac anomalies were isomerism of left atrial appendages, interrupted IVC and azygos vein continuation. Of the 10 positive cases, 8 fetus were diagnosed of RAI and 2 were diagnosed of LAI by prenatal ultrasonic examination or fetal autopsy. The detection rate was 8/30 (26.7%) for RAI and 2/16 (12.5%) for LAI.

Conclusion

This study outlines the way for a substantial improvement in the diagnostic yield of prenatal genetic disorders in Htx through WES and WGS. Our experience also expanded the knowledge of the clinical phenotype of known genetic conditions. Our results indicate that the proportion of SNV in Htx of prenatal cases was significantly higher than that in patients with other congenital heart abnormalities, and the recessive inheritance occurred in a higher proportion in Htx. Our results have important implications for clinical management and genetic counseling of Htx.

Acknowledgement/Funding

Ministry of Science and Technology of the People's Republic of China

P4647Next generation sequencing in 83 fetal left-sided CHDs reveals the entire genetic architecture of left-sided CHDs in fetal population

Background

No data is available for the contribution of single gene disorders (SGDs) to left-sided congenital heart defects (LSCHDs) in the fetal population.

Purpose

The aim of this study was to explore the entire genetic architecture of LSCHDs, especially the contribution of SGDs in a cohort of fetal LSCHDs.

Methods

Low-pass whole genome sequencing (WGS) and whole exome sequencing (WES) were performed on specimens from 83 deceased fetuses with lSCHDs, including 48 HLHS, 22 CoA, 5 AS, 3 AAH, 2 AS+CoA and 1 case of AA, AS+MS, MA. Sequencing was predominantly performed in fetus-parent trios (n=63, 75.9%), or in fetus only (n=20, 24.1%).

Results

34.9% (n=29) of the 83 fetal left-sided CHDs were identified with related genetic abnormalities. WGS analysis identified 14 (16.9%) with chromosomal abnormalities, including 6 (7.2%) aneuploidies and 8 (9.6%) pathogenic copy number variants (CNVs). WES analysis of the remaining 69 cases without chromosomal abnormalities identified 15 (15/69, 21.7%) with pathogenic/likely pathogenic variants. Of these 15 cases, KMT2D was the most frequently mutated gene (7/69, 10.1%), followed by NOTCH1 (4/69, 2.5%). Compound heterozygosity was identified in 3 genes (DNAH11, POFUT1, CRB2) that are not yet well established as CHD genes. Finally, we also observed a LOF variant in NONO (X-linked) that was maternally transmitted to an affected male case.

The genetic results of this cohort Aneuploidies Trisomy 18 4 Turner syndrome 2 CNVs 11q terminal deletion 3 1p36 deletion 1 15q terminal deletion 1 7q11.23 deletion 1 4p terminal deletion 1 12q complex internal duplication 1 SGDs AD (KMT2D = 7; NOTCH1 = 4) 11 AR (DNAH11, POFUT1, CRB2) 3 X-recessive (NONO) 1 AD: autosomal dominant; AR: autosomal recessive.

Conclusions

Our experience supports that SGDs contribute a significant part to the pathogenesis of fetal CHDs, WES has the potential to provide molecular diagnoses in fetal left-sided CHDs without chromosomal abnormalities. KMT2D mutations accounted for a large fraction of left-sided CHDs in fetal population. If the KMT2D mutation is detected, further diagnosis of Kabuki syndrome should be considered.

Known-component metal artifact reduction (KC-MAR) for cone-beam CT

Intraoperative cone-beam CT (CBCT) is increasingly used for surgical navigation and validation of device placement. In spinal deformity correction, CBCT provides visualization of pedicle screws and fixation rods in relation to adjacent anatomy. This work reports and evaluates a method that uses prior information regarding such surgical instrumentation for improved metal artifact reduction (MAR). The known-component MAR (KC-MAR) approach achieves precise localization of instrumentation in projection images using rigid or deformable 3D-2D registration of component models, thereby overcoming residual errors associated with segmentation-based methods. Projection data containing metal components are processed via 2D inpainting of the detector signal, followed by 3D filtered back-projection (FBP). Phantom studies were performed to identify nominal algorithm parameters and quantitatively investigate performance over a range of component material composition and size. A cadaver study emulating screw and rod placement in spinal deformity correction was conducted to evaluate performance under realistic clinical imaging conditions. KC-MAR demonstrated reduction in artifacts (standard deviation in voxel values) across a range of component types and dose levels, reducing the artifact to 5-10 HU. Accurate component delineation was demonstrated for rigid (screw) and deformable (rod) models with sub-mm registration errors, and a single-pixel dilation of the projected components was found to compensate for partial-volume effects. Artifacts associated with spine screws and rods were reduced by 40%-80% in cadaver studies, and the resulting images demonstrated markedly improved visualization of instrumentation (e.g. screw threads) within cortical margins. The KC-MAR algorithm combines knowledge of surgical instrumentation with 3D image reconstruction in a manner that overcomes potential pitfalls of segmentation. The approach is compatible with FBP-thereby maintaining simplicity in a manner that is consistent with surgical workflow-or more sophisticated model-based reconstruction methods that could further improve image quality and/or help reduce radiation dose.

Image quality and dose characteristics for an O-arm intraoperative imaging system with model-based image reconstruction

PURPOSE

To assess the imaging performance and radiation dose characteristics of the O-arm CBCT imaging system (Medtronic Inc., Littleton MA) and demonstrate the potential for improved image quality and reduced dose via model-based image reconstruction (MBIR).

METHODS

Two main studies were performed to investigate previously unreported characteristics of the O-arm system. First is an investigation of dose and 3D image quality achieved with filtered back-projection (FBP) - including enhancements in geometric calibration, handling of lateral truncation and detector saturation, and incorporation of an isotropic apodization filter. Second is implementation of an MBIR algorithm based on Huber-penalized likelihood estimation (PLH) and investigation of image quality improvement at reduced dose. Each study involved measurements in quantitative phantoms as a basis for analysis of contrast-to-noise ratio and spatial resolution as well as imaging of a human cadaver to test the findings under realistic imaging conditions.

RESULTS

View-dependent calibration of system geometry improved the accuracy of reconstruction as quantified by the full-width at half maximum of the point-spread function - from 0.80 to 0.65 mm - and yielded subtle but perceptible improvement in high-contrast detail of bone (e.g., temporal bone). Standard technique protocols for the head and body imparted absorbed dose of 16 and 18 mGy, respectively. For low-to-medium contrast (<100 HU) imaging at fixed spatial resolution (1.3 mm edge-spread function) and fixed dose (6.7 mGy), PLH improved CNR over FBP by +48% in the head and +35% in the body. Evaluation at different dose levels demonstrated 30% increase in CNR at 62% of the dose in the head and 90% increase in CNR at 50% dose in the body.

CONCLUSIONS

A variety of improvements in FBP implementation (geometric calibration, truncation and saturation effects, and isotropic apodization) offer the potential for improved image quality and reduced radiation dose on the O-arm system. Further gains are possible with MBIR, including improved soft-tissue visualization, low-dose imaging protocols, and extension to methods that naturally incorporate prior information of patient anatomy and/or surgical instrumentation.

Long-term efficacy and safety of sonidegib in patients with locally advanced and metastatic basal cell carcinoma: 30-month analysis of the randomized phase 2 BOLT study

BACKGROUND

Patients with locally advanced basal cell carcinoma (laBCC) or metastatic BCC (mBCC), two difficult-to-treat populations, have had limited treatment options. Sonidegib, a hedgehog pathway inhibitor (HPI), was approved in laBCC based on results from the BOLT trial.

OBJECTIVE

To evaluate long-term efficacy and safety of sonidegib in laBCC and mBCC in the BOLT 18- and 30-month analyses.

METHODS

BOLT (NCT01327053, ClinicalTrials.gov), a double-blind phase 2 study, enrolled patients from July 2011 until January 2013. Eligible HPI-treatment-naïve patients with laBCC not amenable to curative surgery/radiotherapy or mBCC were randomized 1 : 2 to sonidegib 200 mg (laBCC, n = 66; mBCC, n = 13) or 800 mg (laBCC, n = 128; mBCC, n = 23). Tumour response was assessed per central and investigator review.

RESULTS

With 30 months of follow-up, among patients treated with sonidegib 200 mg (approved dose), objective response rates were 56.1% (central) and 71.2% (investigator) in laBCC and 7.7% (central) and 23.1% (investigator) in mBCC. Tumour responses were durable as follows: median duration of response was 26.1 months (central) and 15.7 months (investigator) in laBCC and 24.0 months (central) and 18.1 months (investigator) in mBCC. Five patients with laBCC and three with mBCC in the 200-mg arm died. Median overall survival was not reached in either population; 2-year overall survival rates were 93.2% (laBCC) and 69.3% (mBCC). In laBCC, efficacy was similar regardless of aggressive or non-aggressive histology. Sonidegib 200 mg continued to have a better safety profile than 800 mg, with lower rates of grade 3/4 adverse events (43.0% vs. 64.0%) and adverse events leading to discontinuation (30.4% vs. 40.0%).

CONCLUSION

Sonidegib continued to demonstrate long-term efficacy and safety in these populations. These data support the use of sonidegib 200 mg per local treatment guidelines.

Technical Note: Known-Component Registration for Robotic Drill Guide Positioning

A method for x-ray-guided robotic positioning of surgical instruments is reported and evaluated in preclinical studies of spine pedicle screw placement with the aim of improving delivery of transpedicle drills and screws. The known-component registration (KC-Reg) algorithm was used to register the 3D patient CT and the surface model of a drill guide to intraoperatively acquired 2D radiographs. Resulting transformations, combined with offline hand-eye calibration, drive a robotically-held drill guide to target trajectories established in the preoperative patient CT. The proposed method was assessed against more conventional surgical tracker guidance, and robustness to clinically realistic errors was tested in phantom and cadaver studies. Target registration error (TRE) was computed as drill guide deviation from the planned trajectory. The KC-Reg approach resulted in 1.51 ± 0.51 mm error at tooltip and 1.01 ± 0.92° in approach angle, showing comparable performance to the tracker-guided approach. In cadaver studies with anatomical deformation, TRE of 2.31 ± 1.05 mm and 0.66 ± 0.62° were observed, with statistically improved performance over a surgical tracker through registration of locally rigid bony anatomy. X-ray guidance offers an accurate means of driving robotic systems that is compatible with conventional fluoroscopic workflow. Specifically, such procedures involve multi-planar fluoroscopic views that are qualitatively interpreted by the surgeon; the KC-Reg approach accomplishes this using the same multi-planar views to provide greater quantitative accuracy and valuable guidance and QA. The method was robust against anatomical deformation due to the radiographic scene's local nature used in registration, presenting a potentially major surgical benefit.

[Dynamic detection of surface blood flow in rat heart and its application in real time identification of myocardial infarction model]

Objective: To establish a method for monitoring the surface blood flow in the heart of rats, and to clarify the relationship between the degree of myocardial infarction and the blood perfusion on the surface of the heart, so as to provide a new indicator for the identification of rat myocardial infarction model. Methods: The rats were divided into control group (n=23) and model group (n=107), the rat hearts were scanned by the laser doppler perfusion imager before and after operation respectively, and the data was analyzed to acquire the rate of surface blood flow change of the heart. Myocardial infarction size of model group was detected by NBT. Model group were divided into three subgroups of mild myocardial infarction, moderate myocardial infarction and severe myocardial infarction according to the myocardial infarction size, and an analysis was made on the correlativity between rate of surface blood flow change of the heart and myocardial infarction size. Results: Myocardial infarction size was highly correlated to the rate of surface blood flow change of the heart in model group (r=0.849 6, P<0.000 1). There was no significant correlation between infarction size and heart blood flow in the mild myocardial infarction subgroup (r=-0.133 6, P>0.05), while the correlation in moderate myocardial infarction was significant (r=0.721 7, P<0.000 1), and the highest correlation was shown in severe myocardial infarction subgroup (r=0.910 2, P<0.000 1). Conclusion: The heart surface blood flow has a close relationship with the myocardial infarction size in rat, so the change of heart blood perfusion can beused as an effective reference to establish and identify rat myocardial infarction model.

An integrated analysis identifies STAT4 as a key regulator of ovarian cancer metastasis

Epithelial ovarian cancer (EOC) is one of the most common gynecological cancers, with diagnosis often at a late stage. Metastasis is a major cause of death in patients with EOC, but the underlying molecular mechanisms remain obscure. Here, we utilized an integrated approach to find potential key transcription factors involved in ovarian cancer metastasis and identified STAT4 as a critical player in ovarian cancer metastasis. We found that activated STAT4 was overexpressed in epithelial cells of ovarian cancer and STAT4 overexpression was associated with poor outcome of ovarian cancer patients, which promoted metastasis of ovarian cancer in both in vivo and in vitro. Although STAT4 mediated EOC metastasis via inducing epithelial-to-mesenchymal transition (EMT) of ovarian cancer cells in vivo, STAT4 failed to induce EMT directly in vitro, suggesting that STAT4 might mediate EMT process via cancer-stroma interactions. Further functional analysis revealed that STAT4 overexpression induced normal omental fibroblasts and adipose- and bone marrow-derived mesenchymal stem cells to obtain cancer-associated fibroblasts (CAF)-like features via induction of tumor-derived Wnt7a. Reciprocally, increased production of CAF-induced CXCL12, IL6 and VEGFA within tumor microenvironment could enable peritoneal metastasis of ovarian cancer via induction of EMT program. In summary, our study established a model that STAT4 promotes ovarian cancer metastasis via tumor-derived Wnt7a-induced activation of CAFs.

Effects of preheating temperature, moisture, and sodium metabisulfite content on quality of noodles prepared from maize flour or meal / Efecto de la temperatura de precalentamiento, humedad y contenido de metabisulfito de sodio en la calidad de fideos de harina o de sémola de maíz

Preheating temperature, maize flour particle size, and levels of water and sulfite were tested during preparation of maize noodles. Heating a mixture of maize flour and water (43-45 % moisture) at 90-95 °C was required to extrude maize noodles using a pasta maker. Maize flour with smaller par ticle size yielded better noodles than did maize meal. Addition of sulfite enabled production of noodles at lower processing temperatures, however, cooking losses increased. Addition of more water yielded noodles that required longer cooking time, but decreased cooking losses. Functionalities of starch and protein in raw ingredients and in products were determined. Starch gelatinized and retrograded during processing of maize extrudates, as indicated by changes in pasting viscosity curves. Above 40 °C, maize proteins increased mixing viscosity of dough. Increased integrity of cooked maize noodles, however, corresponded to increased amounts of gelatinized and retrograded starch.

3D-Printed Biodegradable Polymeric Vascular Grafts

Congenital heart defect interventions may benefit from the fabrication of patient-specific vascular grafts because of the wide array of anatomies present in children with cardiovascular defects. 3D printing is used to establish a platform for the production of custom vascular grafts, which are biodegradable, mechanically compatible with vascular tissues, and support neotissue formation and growth.

Intracavernous delivery of clonal mesenchymal stem cells rescues erectile function in the streptozotocin-induced diabetic mouse

The major hurdle for the clinical application of stem cell therapy is the heterogeneous nature of the isolated cells, which may cause different treatment outcomes. The aim of this study was to examine the effectiveness of mouse clonal bone marrow-derived stem cells (BMSCs) obtained from a single colony by using subfractionation culturing method for erectile function in diabetic animals. Twelve-week-old C57BL/6J mice were divided into four groups: controls, diabetic mice, and diabetic mice treated with a single intracavernous injection of PBS (20 μL) or clonal BMSCs (3 × 10(5) cells/20 μL). Clonal BMSCs were isolated from 5-week-old C3H mice. Two weeks after treatment, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was stained with antibodies to PECAM-1, smooth muscle α-actin, neuronal nitric oxide synthase (nNOS), neurofilament, and phosphorylated endothelial NOS (phospho-eNOS). We also performed Western blot for phospho-eNOS, and eNOS in the corpus cavernosum tissue. Local delivery of clonal BMSCs significantly restored cavernous endothelial and smooth muscle cell contents, and penile nNOS and neurofilament contents, and induced eNOS phosphorylation (Ser1177) in diabetic mice. Intracavernous injection of clonal BMSCs induced significant recovery of erectile function, which reached 80-90% of the control values. Clonal BMSCs successfully restored erectile function through dual angiogenic and neurotrophic effects in diabetic mice. The homogenous nature of clonal mesenchymal stem cells may allow their clinical applications and open a new avenue through which to treat diabetic erectile dysfunction.

KiSS1-induced GPR54 signaling inhibits breast cancer cell migration and epithelial-mesenchymal transition via protein kinase D1

The metastasis suppressor protein Kisspeptin regulates cancer cell proliferation and motility through its receptor, GRP54. However, the critical downstream effectors remain unclear. In this study, we investigated GPR54 signaling in breast cancer cells. Kisspeptin stimulation caused a decrease in migration of multiple breast cancer cell lines. Also, Kisspeptin inhibited MDA-MB-231 cell colony formation in 3D matrigel culture and in soft agar. Kisspeptin treatment elevated phosphorylated PKD1 in a PKC-dependent manner. However, knockdown of either GPR54 or PKD1 increased breast cancer cell migration and invasion. Furthermore, GPR54 knockdown blocked Kisspeptin-induced phosphorylation of PKD1. Finally, Kisspeptin stimulation induced a PKD1 phosphorylation-dependent decrease in expression of Slug, a transcription factor that drives epithelial-mesenchymal transition (EMT), and a concomitant increase in E-cadherin expression. Therefore, KiSS1/GPR54 signaling through PKD1 acts to maintain the epithelial state and to inhibit breast cancer cell invasiveness, and exerts functions associated with its role as a metastasis suppressor.

Contrasting biofunctionalization strategies for the enhanced endothelialization of biodegradable vascular grafts

Surface modification of biodegradable vascular grafts is an important strategy to improve the in situ endothelialization of tissue engineered vascular grafts (TEVGs) and prevent major complications associated with current synthetic grafts. Important strategies for improving endothelialization include increasing endothelial cell mobilization and increased endothelial cell capture through biofunctionalization of TEVGs. The objective of this study was to assess two biofunctionalization strategies for improving endothelialization of biodegradable polyester vascular grafts. These techniques consisted of cross-linking heparin to graft surfaces to immobilize vascular endothelial growth factor (VEGF) or antibodies against CD34 (anti-CD34Ab). To this end, heparin, VEGF, and anti-CD34Ab attachment and quantification assays confirmed the efficacy of the modification strategy. Cell attachment and proliferation on these groups were compared to unmodified grafts in vitro and in vivo. To assess in vivo graft functionality, the grafts were implanted as inferior vena cava interpositional conduits in mice. Modified vascular grafts displayed increased endothelial cell attachment and activity in vivo, according to microscopy techniques, histological results, and eNOS expression. Inner lumen diameter of the modified grafts was also better maintained than controls. Overall, while both functionalized grafts outperformed the unmodified control, grafts modified with anti-CD34Ab appeared to yield the most improved results compared to VEGF-loaded grafts.

Efficient inhibition of intraperitoneal human ovarian cancer growth by short hairpin RNA targeting CD44

CD44 is one member of a big glycoprotein family involved in adhesion of cells or cells and extracellular matrix (ECM). The heavily glycosylated CD44 has been proved to be a major receptor of hyaluronan and a marker of stem cells in ovarian cancer. Here, using short hairpin (shRNA) against CD44, we demonstrate that knockdown CD44 could inhibit cancer growth efficiently compared with controls. Plasmid targeting CD44 gene (pshCD44) or non-relative control sequences (pshHK) was constructed and delivered to ovarian cancer by biodegradable poly D, L-Lactide-co-glycolide acid nanoparticles (PLGANPs). Nude mice were utilized in an intraperitoneal model of ovarian carcinomatosis to assess antitumor efficacy in vivo. Antitumor efficacy was estimated by changes in tumor weights, proliferation (Ki-67), apoptosis (TUNEL) and angiogenesis (CD31 staining and alginate-encapsulated tumor beads assay) in tumor cells. As results, pshCD44 or pshHK could be effectively transfected into SKOV-3 cells by PLGANPs. Tumor weight in pshCD44/PLGANPs group was suppressed by 45% and 50% compared with those in pshHK/PLGANPs and untreated group, respectively (Ps < 0.001). Inhibition of cell proliferation, induction of apoptosis and reduction of angiogenesis in tumor cells of pshCD44/PLGANPs group also show significant difference compared with those in control groups (Ps < 0.05), respectively. These results indicate that pshCD44 delivered by PLGANPs might be a potential approach in ovarian cancer therapy, and point towards a mechanism involving the inhibition of angiogenesis, cellular proliferation and the induction of apoptosis.

Administration of PLGA nanoparticles carrying shRNA against focal adhesion kinase and CD44 results in enhanced antitumor effects against ovarian cancer

The two membrane-bound proteins, focal adhesion kinase (FAK) and CD44, are involved in processes critical to cancer progression. FAK has an active role in angiogenesis, cell proliferation and cell apoptosis, whereas the heavily glycosylated CD44 has been implicated in cancer metastasis. Here, using short hairpin RNA (shRNA) against FAK and CD44, we demonstrate that simultaneous knockdown of both these genes inhibits cancer growth more efficiently than knockdown of either gene individually. Plasmids targeting these genes or non-relative control sequences were constructed and delivered to ovarian cancer targets by biodegradable poly D,L-lactide-co-glycolide acid nanoparticles (PLGANPs). Nude mice were utilized in an intraperitoneal model of ovarian carcinomatosis to assess antitumor efficacy in vivo. Single gene knockdown resulted in significantly smaller tumors than those observed in the empty-vector control (P's<0.001). More importantly, knockdown of both genes resulted in tumors smaller than both the empty-vector group (P<0.0001) and the single gene knockdown groups (P's<0.001). Knockdown of both FAK and CD44 resulted in tumors with inhibited angiogenesis, reduced proliferation and increased apoptosis as compared with controls (P's<0.001) and single knockdown groups (P's<0.05). These results indicate that dual knockdown of FAK and CD44 in the tumors of patients with ovarian cancer may have an enhanced therapeutic effect, and point toward a mechanism involving the inhibition of angiogenesis, cellular proliferation and the induction of apoptosis.

The safety and efficacy of live attenuated influenza vaccine in young children with asthma or prior wheezing

In the European Union and Canada, an Ann Arbor strain live attenuated influenza vaccine (LAIV) is approved for use in children aged 2–17 years, including those with mild to moderate asthma or prior wheezing. The safety and efficacy of LAIV versus trivalent inactivated influenza vaccine (TIV) in children with asthma aged 6–17 years have been demonstrated. However, few data are available for children younger than 6 years of age with asthma or prior wheezing. Safety and efficacy data were collected for children aged 2–5 years with asthma or prior wheezing from two randomized, multinational trials of LAIV and TIV (N = 1,940). Wheezing, lower respiratory illness, and hospitalization were not significantly increased among children receiving LAIV compared with TIV. Increased upper respiratory symptoms and irritability were observed among LAIV recipients (p < 0.05). Relative efficacies were consistent with the results observed in the overall study populations, which demonstrated fewer cases of culture-confirmed influenza illness in LAIV compared with TIV recipients. Study results support the safety and efficacy of LAIV among children aged 2–17 years with mild to moderate asthma or a history of wheezing. Data regarding LAIV use are limited among individuals with severe asthma or active wheezing within the 7 days before vaccination.

Initial evaluation of the use of USPIO cell labeling and noninvasive MR monitoring of human tissue-engineered vascular grafts in vivo

This pilot study examines noninvasive MR monitoring of tissue-engineered vascular grafts (TEVGs) in vivo using cells labeled with iron oxide nanoparticles. Human aortic smooth muscle cells (hASMCs) were labeled with ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles. The labeled hASMCs, along with human aortic endothelial cells, were incorporated into eight TEVGs and were then surgically implanted as aortic interposition grafts in a C.B-17 SCID/bg mouse host. USPIO-labeled hASMCs persisted in the grafts throughout a 3 wk observation period and allowed noninvasive MR imaging of the human TEVGs for real-time, serial monitoring of hASMC retention. This study demonstrates the feasibility of applying noninvasive imaging techniques for evaluation of in vivo TEVG performance.

Humoral and cellular immunity induced by tumor cell vaccine based on the chicken xenogeneic homologous matrix metalloproteinase-2

Matrix metalloproteinase-2 (MMP-2) has been used as a target for cancer immunotherapy. The activation of immunization by breaking immune tolerance to self-MMP-2 may be one of the promising approaches for the treatment of MMP-2-positive tumors. In this study, we constructed the xenogeneic tumor cell vaccine c-MMP-2 by transfecting CT26 and LLC cells with chicken MMP-2 cDNA constructs. MMP-2-specific autoantibodies in sera and tumor cells were found in mice immunized with c-MMP-2. Protection against tumor growth was evaluated in respect of the relative contributions of autoantibodies, CD4+, and CD8+ T cells. Treatment with this vaccine (c-MMP-2) also prolonged the survival time of mice bearing cancer. The specific cytotoxic T-cell responses suggested that the treatment increased CD8+ T-cell activity. The antitumor activity of c-MMP-2 was abrogated by in vivo depletion of CD4+ and CD8+ T-lymphocytes and improved by adoptive transfer of CD4+ and CD8+ T-lymphocytes from the mice treated with c-MMP-2. An alternative DNA vaccination strategy for cancer therapy was identified in this study by eliciting humoral and cellular immunoresponse with a crossreacting transfectant.

Activation of human peripheral blood immune cells in vitro by sodium stibogluconate (SSG) and SSG/IL-2 combination

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Background: SSG, an inhibitor of SHP-1 and SHP2 which are negative regulatory signaling tyrosine phosphatases, suppressed the growth of murine renal carcinoma (Renca) in combination with IL-2 via an interferon (IFN)-γ+ T cell-dependent mechanism (J Immunol 175:7003–8, 2005). Activation of primary human immune cells by SSG or SSG/IL-2 would provide additional supporting evidence for SSG clinical evaluation in combination with IL-2. Methods: Peripheral blood of healthy and melanoma donors were treated in vitro with SSG or SSG/IL-2 and then subjected to ELISPOT assays and FACS analysis for quantification of TH1 (IFN-γ+) and TH2 (IL-5+) cells. Results: Characterization by ELISPOT assays of peripheral blood identified IFN-γ+ cells with marked increase (9.1x) following SSG/IL-2 treatment in contrast to the modest increases induced by SSG alone (2.1x) at its clinically achievable dose (20 μg/ml) or by IL-2 (3.1x) at its Cmax of low-dose schedule (30 IU/ml). SSG at an even higher dose (100 μg/ml) was less effective alone (1.5x) or in combination with IL-2 (7.8x). IL-5+ cells were not induced by the agents individually or in combination. Induction of peripheral IFN-γ+ cells by SSG/IL-2 was detectable after 4 and 16 h. Increased effectiveness of the SSG/IL-2 combination vs. the individual agents in inducing IFN-γ+ cells in vitro was detected by ELISPOT assays in the peripheral blood from 7 healthy donors and 6 melanoma patients. FACS analysis showed that the combination induced IFN-γ+ cells in the CD4+ and CD8+ lymphocytes and also increased lymphocytes expressing the activation marker CD69 in both CD4+ (2–5x) and CD4− populations (∼ 3x). Conclusion: SSG, a compound used clinically for treatment of leishmaniasis, can interact with IL-2 in vitro to activate immune cells in peripheral blood of healthy and melanoma donors. Results provide further rationale, in addition to the mouse tumor data, for proof of concept clinical trials for effecting augmentation of IL-2 through inhibition of negative regulatory signaling phosphatases.

No significant financial relationships to disclose.

Effects of sodium stibogluconate on differentiation and proliferation of human myeloid leukemia cell lines in vitro

PTPases are key signaling molecules and targets for developing novel therapeutics. We have studied the in vitro biological activity of PTPase inhibitor sodium stibogluconate (SS) on differentiation and proliferation of myeloid leukemia cell lines (NB4, HL-60 and U937). SS (250 microg/ml, 6 days) induced 87% of NB4 cells to reduce nitroblue tetrazolium (NBT), in comparison to the 90% induced by ATRA (1 microM, 6 days). SS treatment of NB4 cells resulted in an increase of CD11b expression and of a morphologically more mature population, coincident with growth arrest at S phase and increased cell death. The effect of SS on NB4 differentiation was irreversible and required continuous drug exposure. SS (400 microg/ml, 6 days) induced 60% and 55% of NBT-positive cells in HL-60 and U937 cell lines, which were augmented in the presence of GM-CSF (25 ng/ml) to levels (85% and 81%, respectively) comparable to those induced by ATRA. SS induced increased tyrosine phosphorylation of cellular proteins in the AML cell lines and inactivated SHP-1 PTPase in NB4 cells, consistent with SS functioning as a PTPase inhibitor in the leukemia cells. These results provide the first evidence of an anti-leukemia activity of SS as a PTPase inhibitor.

Transcriptional repression of type I procollagen genes during adipocyte differentiation

Adipocyte differentiation is a very complex process in which whole-cell changes are accompanied. Among them, type I procollagen gene has been shown to specifically decrease during adipocyte differentiation; however, little is known about the molecular mechanism. To examine how type I procollagen gene expression is regulated at the level of transcription during adipocyte differentiation, 3T3-L1 preadipocyte cell line was used as an in vitro model. Northern blot analysis demonstrated that mRNA expression of type I procollagen gene was dramatically reduced during adipocyte differentiation. Time-course analysis indicated that decrease in mRNA expression occurred at early stage of differentiation. Studies on several stable cell lines showed that transcriptional activities of both alpha1 and alpha2 promoters decreased significantly during adipocyte differentiation. Despite extensive deletion-promoter analyses, however, we could not identify the cis-element responsible for the switch-off of type I procollagen gene during adipocyte differentiation, suggesting that the transcriptional repression of this gene occur through general transcription machinery rather than a specific cis-element. In conclusion, down-regulation of type I procollagen mRNA expression during adipocyte differentiation is due to repression of its promoter activity through general transcription machinery.

The carboxyl terminus of the granulocyte colony-stimulating factor receptor, truncated in patients with severe congenital neutropenia/acute myeloid leukemia, is required for SH2-containing phosphatase-1 suppression of Stat activation

The G-CSF receptor transduces signals that regulate the proliferation, differentiation, and survival of myeloid cells. A subgroup of patients with severe congenital neutropenia (SCN) has been shown to harbor mutations in the G-CSF receptor gene that resulted in the truncation of the receptor's carboxyl-terminal region. SCN patients with mutations in the G-CSF receptor gene are predisposed to acute myeloid leukemia. The truncated receptors from SCN/acute myeloid leukemia patients mediate augmented and sustained activation of Stat transcription factors and are accordingly hyperactive in inducing cell proliferation and survival but are defective in inducing differentiation. Little is known about the molecular mechanisms underlying the negative role of the receptor's carboxyl terminus in the regulation of Stat activation and cell proliferation/survival. In this study, we provide evidence that SH2-containing phosphatase-1 (SHP-1) plays a negative regulatory role in G-CSF-induced Stat activation. We also demonstrate that the carboxyl terminus of the G-CSF receptor is required for SHP-1 down-regulation of Stat activation induced by G-CSF. Our results indicate further that this regulation is highly specific because SHP-1 has no effect on the activation of Akt and extracellular signal-related kinase1/2 by G-CSF. The data together strongly suggest that SHP-1 may represent an important mechanism by which the carboxyl terminus of the G-CSF receptor down-regulates G-CSF-induced Stat activation and thereby inhibits cell proliferation and survival in response to G-CSF.