Abstract P4-07-06: MicroRNAs associated with acquired taxane resistance in a breast cancer cell line model

Background: Acquired chemoresistance remains the major cause of therapeutic failure in the treatment of breast cancer. Improved knowledge of the transition from drug sensitive to resistant breast cancer will pave the way for novel preventative and therapeutic strategies. MicroRNAs (miRNA) are endogenous, small non-coding RNAs that regulate gene expression by targeting the 3'UTR region of messenger RNAs. There is a growing body of evidence to suggest miRNAs may be involved in the development of chemoresistance and may play a role in the regulation of drug resistance pathways.

Methods: An in vitro model of paclitaxel resistance was developed through the generation of resistant MDA-MB-231 cell lines by serial culture in escalating doses of taxane until resistance was achieved. The chemoresistant model was used to compare differential miRNA expression with the sensitive, parental line using the Nanostring® platform, analysing 800 human miRNAs. Confirmation of differential expression was performed by QRT-PCR.

Results: This analysis resulted in 30 significantly altered miRNA (1.5 fold, p value < 0.05) at 25nM paclitaxel and 48 significantly altered miRNA at 50nM paclitaxel. The top up-regulated miRNA cluster in MDA-MB-231 25PACR is hsa-miR-548l (fold change: 2.89, p value: 0.016) and top down-regulated was hsa-miR-449a (fold change: -4.1. p value: 0.001). In MDA-MB-231 50PACR the top up-regulated miRNA cluster is hsa-miR-193a-5p (fold change: 3.746, p value: 0.008) and the top down-regulated miRNA cluster is hsa-miR-135a (fold change: -4.085, p value: 0.001). To explore the molecular mechanisms of the differentially expressed miRNAs in paclitaxel resistance, targets were predicted by in silico analysis. Pathways and networks designated by miRNA targets included the cell cycle, PI3K/Akt pathways and focal adhesion.

Conclusion: In this study we identified candidate resistance-associated miRNAs which were differentially expressed between in vitro derived paclitaxel resistant MDA-MB-231 and the sensitive parental line. Further validation to ascertain their role in the transition to a chemoresistant phenotype is currently ongoing.

Citation Format: Taylor KJ, Chong T, D'Costa A, Yao C, Gourley C, Cameron DA, Bartlett JMS, Spears M. MicroRNAs associated with acquired taxane resistance in a breast cancer cell line model [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-07-06.

Use of genotype × environment interaction model to accommodate genetic heterogeneity for residual feed intake, dry matter intake, net energy in milk, and metabolic body weight in dairy cattle

Feed efficiency in dairy cattle has gained much attention recently. Due to the cost-prohibitive measurement of individual feed intakes, combining data from multiple countries is often necessary to ensure an adequate reference population. It may then be essential to model genetic heterogeneity when making inferences about feed efficiency or selecting efficient cattle using genomic information. In this study, we constructed a marker × environment interaction model that decomposed marker effects into main effects and interaction components that were specific to each environment. We compared environment-specific variance component estimates and prediction accuracies from the interaction model analyses, an across-environment analyses ignoring population stratification, and a within-environment analyses using an international feed efficiency data set. Phenotypes included residual feed intake, dry matter intake, net energy in milk, and metabolic body weight from 3,656 cows measured in 3 broadly defined environments: North America (NAM), the Netherlands (NLD), and Scotland (SAC). Genotypic data included 57,574 single nucleotide polymorphisms per animal. The interaction model gave the highest prediction accuracy for metabolic body weight, which had the largest estimated heritabilities ranging from 0.37 to 0.55. The within-environment model performed the best when predicting residual feed intake, which had the lowest estimated heritabilities ranging from 0.13 to 0.41. For traits (dry matter intake and net energy in milk) with intermediate estimated heritabilities (0.21 to 0.50 and 0.17 to 0.53, respectively), performance of the 3 models was comparable. Genomic correlations between environments also were computed using variance component estimates from the interaction model. Averaged across all traits, genomic correlations were highest between NAM and NLD, and lowest between NAM and SAC. In conclusion, the interaction model provided a novel way to evaluate traits measured in multiple environments in which genetic heterogeneity may exist. This model allowed estimation of environment-specific parameters and provided genomic predictions that approached or exceeded the accuracy of competing within- or across-environment models.

Non-inferiority of minimally invasive oesophagectomy: an 8-year retrospective case series

BACKGROUND

The trend towards laparoscopic surgery seen in other specialties has not occurred at the same pace in oesophagectomy. This stems from concerns regarding compromised oncological clearance, and complications associated with gastric tube necrosis and anastomotic failure. We present our experience of minimally invasive oesophagectomy (MIO) compared to open and hybrid surgery. We aim to ascertain non-inferiority of MIO by evaluating impact on survival, oncological clearance by resection margin and lymph node harvest and post-operative complications.

METHODS

Data were sourced retrospectively 2008-2015. Three approaches were studied. MIO (3-stage Mckeown), hybrid (2-stage Ivor Lewis, laparoscopy, thoracotomy) and open (2-stage Ivor Lewis).

RESULTS

Five-year survival was 54.2%. Surgical approach had no significant impact on survival at any stage of disease (Stage 0/I p = 0.98; stage II p = 0.2; stage III p = 0.76). There was no statistically significant difference in oncological clearance by resection margins between procedures when compared by disease stage (p = 0.49). A higher number of nodes were harvested in hybrid [median 27.5 (6-65)] and open surgeries [median 26 (4-54)] than in MIO [median 20 (7-44)] (p > 0.01). Numbers of nodes resected did not impact risk of recurrence [recurrence, median 25 (6-54), no recurrence, 26 (4-65)] (p = 0.25). Anastomotic strictures (22.4%) and potential leaks (17.9%) were more common in MIO (strictures p > 0.01, leaks p = 0.08), although associated morbidity was lower. Respiratory complications were less common in MIO (2.9%) versus hybrid (13.3%) (p = 0.02). Wound infection and chyle leak were also lower (wound 1.5% MIO 3.5% open, p = 0.6; chyle leak 1.5% MIO, 6.7% hybrid, p = 0.2).

CONCLUSIONS

Our results show no negative impact of MIO on survival or oncological clearance. Respiratory and wound complications are lower in MIO, but rates of anastomotic strictures and potential anastomotic leaks are increased. This may be due to the longer length of conduit and subclinical ischaemia at the anastomosis and merits further evaluation.

[To study the effect of intratympanic injection with mouse nerve growth factor and methylprednisolone on sudden deafness]

Objective:To observe the efficacy of intratympanic injection with mouse nerve growth factor and methylprednisolone on the treatment of sudden deafness.Method:One hundred and forty-nine patients diagnosed as sudden deafness were randomly divided into the control group and the observation group. The control group was treated with the conventional medication and methylprednisolone(0.5 ml)+0.9%NaCl(0.5 ml), once every three days for two weeks. The observation group was added with mouse nerve growth factor(0.5 ml) once every three days for two weeks.Result:The total effective rate in the observation group of hearing, tinnitus and vertigo were respective 93.4%, 77.8%,85.2%, which were higher than 80.8%, 63.0%, 67.2%.in the control group.And the differences between them had statistical significance(P< 0.05).Conclusion:Effect of the intratympanic injection with mouse nerve growth factor and methylprednisolone on the treatment of sudden deafness is obvious, which can effectively improve hearing level, and relieve tinnitus and vertigo.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

[Management of endo-graft infection following endovascular repair of abdominal aortic aneurysm]

OBJECTIVE

To summarize our experience in the management of stent-graft infection after endo-vascular aortic repair (EVAR) of abdominal aortic aneurysm (AAA).

METHODS

Data of patients who were diagnosed as endo-graft infection following EVAR and admitted in our center between January 2000 and December 2015 were reviewed. Clinical records including causes of infection, medical history, re-operative procedures, and prognostic data were analysed.

RESULTS

A total of 10 male patients, aged 45-72 years (averaged 62.5 years), were enrolled. Two patients received previous EVAR in our center, accounting for 0.23% of all the 885 EVAR procedures we conducted during the same period. The symptoms related to stent infection, including recurrent fever (100%) and persistent back pain (40%), occured 0 to 27 months (averaged 6.9 months) after EVAR procedure. Eight patients were found to have apparent causes (80%), including 1 case with upper respiratory infection and sepsis, 4 cases with aorto-enteric fistula (AEF) and 3 cases with inflammatory AAA. Except one DNR, other 9 patients received re-operation, including 1 procedure of open debridement and drainage, 1 procedure of endo-graft excision and bilateral axillary-femoral bypass, 7 procedures of endograft excision and axillary-bifemoral bypass. During the follow-up period(2-60 months, averaged 24.1 months), 1 patient was lost, 1 patient died from aortic stump rupture (12.5%) and other 7 patients survived. Bypass occlusion was observed in 1 patient (12.5%) without severe limb ischemia.

CONCLUSIONS

AEF and inflammatory AAA are two leading causes of endo-graft infection following EVAR in our patients. Graft excision and axillofemoral bypass is an acceptable management for this life-threatening morbidity.

[Standardize the endovascular treatment for arteriosclerosis obliterans]

Endovascular therapy has become the first-line strategy for most peripheral artery disease cases. Currently, many guidelines recommend endovascular therapy as the first choice for arteriosclerosis obliterans. Recently, drug-eluting stent and drug-coated balloon are available. The clinical outcomes have been greatly improved with the evolution of devices. However, the long-term outcomes of endovascular therapy for arteriosclerosis obliterans are still not satisfied. Many centers treat arteriosclerosis obliterans using endovascular therapy in appropriately. In this editorial, an evidence-based approach and some strategies will be discussed to standardize the endovascular treatment and improve the result of endovascular therapy for arteriosclerosis obliterans.

Efficacy and safety of combination therapy with vildagliptin and metformin versus metformin uptitration in Chinese patients with type 2 diabetes inadequately controlled with metformin monotherapy: a randomized, open-label, prospective study (VISION)

AIMS

To compare the efficacy and safety of combination of vildagliptin and metformin therapy with metformin uptitration in Chinese patients with type 2 diabetes (T2DM) inadequately controlled with low-dose metformin.

METHODS

In this 24-week prospective, randomized, multicentre, open-label study, patients with T2DM inadequately controlled with metformin ≤1000 mg daily were divided 1 : 1 : 1 : 1 into four prespecified subgroups based on age and body mass index (BMI). Patients in each subgroup were randomized 5 : 1 to receive either vildagliptin (50 mg twice daily) plus metformin [500 mg twice daily; vildagliptin and low-dose metformin (VLDM) group] or metformin uptitration [1000 mg twice daily; high-dose metformin (HDM) group]. The primary endpoint was change in glycated haemoglobin (HbA1c) from baseline at week 24. The key secondary endpoints included percentage of patients achieving target HbA1c without adverse gastrointestinal (GI) events and mean change in fasting plasma glucose (FPG) from baseline to week 24.

RESULTS

A total of 3084 patients were randomized. HbA1c reduction of 0.54% at week 24 in the VLDM group was non-inferior and statistically superior compared with 0.40% in the HDM group (P < 0.0001). VLDM's non-inferiority to HDM was confirmed in the four subgroups and its superiority was shown for all subgroups (p < 0.05) except for the subgroup of patients aged <60 years with a BMI of ≥24 kg/m(2) . Compared with HDM, VLDM significantly increased the percentage of patients achieving HbA1c ≤6.5% and HbA1c ≤6.5% without GI events. FPG levels in the VLDM group were lower at week 24 numerically than in the HDM group. The two treatment arms had similar safety profiles.

CONCLUSIONS

VLDM was non-inferior and statistically superior to HDM in glycaemic control in Chinese patients with T2DM inadequately controlled with low-dose metformin.

Effects of warm acupuncture on breast cancer-related chronic lymphedema: a randomized controlled trial

BACKGROUND

Effective treatment for breast cancer-related chronic lymphedema (bcrl) remains a clinical challenge. Acupuncture and moxibustion treatments have been shown to be beneficial and safe for treating bcrl. In the present randomized controlled trial, we compared the effectiveness of combined acupuncture and moxibustion ("warm acupuncture") with that of diosmin in bcrl.

METHODS

Breast cancer patients who met the inclusion and exclusion criteria (n = 30) were randomized to experimental and control groups (15 per group). On alternate days, patients in the experimental group received 30 minutes of acupuncture at 6 acupoints, with 3 of the needles each being topped by a 3-cm moxa stick. The control treatment was diosmin 900 mg 3 times daily. The control and experimental treatments were administered for 30 days. Outcome measures included arm circumferences (index of effectiveness), range of motion [rom (shoulder joint function)], quality of life, clinical safety, and adverse events.

RESULTS

Measured by the index of effectiveness, bcrl improved by 51.46% in the experimental group and by 26.27% in the control group (p < 0.00001). Effects were greatest at 10 cm above the elbow and at the wrist, where the warm needling was provided. Impairments in shoulder joint rom were minimal at baseline in both treatment groups. However, the roms of rear protraction, abduction, intorsion, and extorsion in the experimental group improved significantly; they did not change in the control group. Self-reported quality of life was significantly better with warm acupuncture than with diosmin. No adverse effects were reported during the treatment period, and laboratory examinations for clinical safety fell within the normal ranges.

CONCLUSIONS

Compared with diosmin, warm acupuncture treatment can effectively reduce the degree of bcrl at the specific acupoints treated and can promote quality of life. Warm acupuncture showed good clinical safety, without any adverse effects on blood or the cardiovascular system.

Abstract P3-07-32: Tumour infiltrating lymphocyte (TIL) and chemokine gene signature predicts for benefit of anthracycline-containing chemotherapy in breast cancer patients

Background: The contribution of immune cells has long been appreciated in tumour development and disease progression; however, their translational potential as cancer-associated prognostic and predictive markers was only recently recognized. High densities of tumour-infiltrating lymphocytes (TILs) correlate with improved clinical outcome in breast cancer; whether TILs also predict anthracycline benefit in all, or only a particular subgroup, of breast cancer patients remains largely unknown. Furthermore, since identification of TILs is generally based on H&E staining, it has not previously been possible to evaluate relative contribution of distinct T-cell types, and B cells, to patient outcome.

Methods: We assessed 290 patient samples from the BR9601 adjuvant breast cancer trial for the capacity of TIL contexture to predict for anthracycline (E-CMF) benefit over CMF. We immunoprofiled patient samples on the Nanostring platform to gain insight into the impact of lymphocyte populations predicting for anthracycline benefit. Our immunoprofiling panel included 38 genes representing TIL-gene signatures and chemokines that may be responsible for recruiting TILs to the tumour site.

Results: The analyses revealed two important findings. First, refinement of the 38-gene panel resulted in the generation of a novel 9-gene signature that includes cytotoxic T lymphocytes (CTL) and chemokine genes. Low CTL gene expression correlated with ER+ expression while high expression correlated with ER- expression (p&lt;0.0001), consistent with the notion that high TIL densities are predominantly observed in non-luminal breast cancers. Second, in an univariate Cox regression analysis, this 9-gene signature was a predictive biomarker of anthracycline benefit with respect to breast-cancer specific OS (HR: 0.371, 95%CI 0.158-0.868, p=0.022) and DRFS (HR: 0.395, 95%CI 0.172-0.907, p=0.028); this effect was no longer significant after adjustment for other prognostic factors (OS HR: 0.437, 95%CI 0.166-1.150, p=0.094; DRFS HR: 0.488, 95%CI 0.185-1.287, p=0.147).

Conclusion: This study highlights the significance of assessing the entire tumour since TILs, tumour and stromal cells collectively engage in a complex interplay that contributes to disease development and progression. Importantly, it reveals that not only CTLs but also chemokines may be clinically relevant and should be validated as potential biomarkers of anthracycline benefit and as therapeutic targets.

Citation Format: Braunstein M, Yao C, Lyttle N, Liao L, Boutros PC, Twelves CJ, Bartlett JMS, Spears M. Tumour infiltrating lymphocyte (TIL) and chemokine gene signature predicts for benefit of anthracycline-containing chemotherapy in breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-32.

Abstract P3-06-03: Downregulation of histone H2A and H2B pathways is associated with anthracycline sensitivity in breast cancer

Background: Meta-analyses performed by the Early Breast Cancer Trialists Collaborative Group demonstrated a significant increase in disease free and overall survival through the addition of anthracyclines to polychemotherapy. Anthracyclines have, however, significant toxicities including cardiotoxicity and leukaemia. It is, therefore, imperative to identify those patients who will benefit from adjuvant anthracycline treatment; other patients could then be spared unnecessary toxicities and be considered for alternative adjuvant therapy. Several markers that may predict anthracycline benefit have been explored in patient cohorts (HER2, TOP2A, Ch17CEP and TIMP1) with limited success.

Methods: To identify markers that are clinically-relevant, we generated MDA-MB-231, MCF7, SKBR3 and ZR-75-1 breast cancer cell lines sensitive and resistant to epirubicin to identify pathways contributing to anthracycline resistance. A complementary approach including gene expression analyses to identify molecular pathways involved in resistance, and small-molecule inhibitors to reverse resistance were performed. RNA was extracted from patients in the BR9601 adjuvant trial evaluating the addition of epirubicin (E) to CMF and analysed through Nanostring technology. Log-rank analyses explored the predictive values of the signatures on distant relapse-free survival (DRFS). Cox-regression models tested independent predictive value on DRFS in the presence of treatment, age, tumour size, nodal status, ER status and grade, and treatment by marker interactions.

Results: Gene expression analysis identified upregulaton of a histone gene module in all four cell lines which was validated by qRT-PCR. Histone deacetylase small-molecule inhibitors reversed resistance and were cytotoxic for epirubicin-resistant cell lines, with IC50's ranging from 0.1-3.69µM, confirming that histone pathways are associated with epirubicin resistance. Gene expression analysis of the 18-gene histone module in the BR9601 clinical cohort revealed that patients whose tumour had low expression had an increased DRFS (HR: 0.35, 95%CI 0.17-0.73, p=0.005) when treated with E-CMF compared with patients treated with CMF alone. Conversely, there was no apparent benefit of E-CMF vs CMF in patients with high histone module expression (HR: 0.96, 95%CI 0.58-1.59, p=0.87). After multivariate analysis and adjustment for HER2 status, nodal status, age, grade and ER status, the treatment by marker interaction was 0.35 (95%CI 0.13-0.96, p=0.042) for DRFS.

Conclusion: Histone gene expression was an independent predictor of anthracycline benefit in terms of DRFS. In vitro data demonstrated that resistance could be reversed with histone deacetylase small-molecule inhibitors. The histone signature identified could be a potential theranostic candidate for patients with early breast cancer.

Citation Format: Spears M, Braunstein M, Liao L, Yao C, Lyttle N, Lobo N, Taylor KJ, Krzyzanowski PM, Kalatskaya I, Marcellus R, Stein L, Boutros P, Twelves CJ, Bartlett JMS. Downregulation of histone H2A and H2B pathways is associated with anthracycline sensitivity in breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-06-03.

Aldehyde-functionalized porous nanocellulose for effective removal of heavy metal ions from aqueous solutions

Nanoscale sorption is a promising strategy for catalyst and purification system design.

Epidemiology of community-onset bloodstream infections in Bouaké, central Côte d'Ivoire

Bacterial bloodstream infections (BSI) account for considerable morbidity worldwide, but epidemiological data from resource-constrained tropical settings are scarce. We analysed 293 blood cultures from patients presenting to a regional referral hospital in Bouaké, central Côte d’Ivoire, to determine the aetiology of community-onset BSI. The prevalence of bacteraemia was 22.5%, with children being most commonly affected. Enterobacteriaceae (predominantly Klebsiella pneumoniae and Salmonella enterica) accounted for 94% of BSI. Staphylococcus aureus was the only relevant Gram-positive pathogen. Clinical signs and symptoms were not significantly associated with blood culture positivity after controlling for malaria.

Short communication: Use of single nucleotide polymorphism genotypes and health history to predict future phenotypes for milk production, dry matter intake, body weight, and residual feed intake in dairy cattle

As feed prices have increased, the efficiency of feed utilization in dairy cattle has attracted increasing attention. In this study, we used residual feed intake (RFI) as a measurement of feed efficiency along with its component traits, adjusted milk energy (aMilkE), adjusted dry matter intake (aDMI), and adjusted metabolic body weight (aMBW), where the adjustment was for environmental factors. These traits may also be affected by prior health problems. Therefore, the carryover effects of 3 health traits from the rearing period and 10 health traits from the lactating period (in the same lactation before phenotype measurements) on RFI, aMilkE, aDMI, and aMBW were evaluated. Cows with heavier birth weight and greater body weight at calving of this lactation had significant increases in aMilkE, aDMI, and aMBW. The only trait associated with RFI was the incidence of diarrhea early in the lactation. Mastitis and reproductive problems had negative carryover effects on aMilkE. The aMBW of cows with metabolic disorders early in the lactation was lower than that of unaffected cows. The incidence of respiratory disease during lactating period was associated with greater aMBW and higher aDMI. To examine the contribution of health traits to the accuracy of predicted phenotype, genomic predictions were computed with or without information regarding 13 health trait phenotypes using random forests (RF) and support vector machine algorithms. Adding health trait phenotypes increased prediction accuracies slightly, except for prediction of RFI using RF. In general, the accuracies were greater for support vector machine than RF, especially for RFI. The methods described herein can be used to predict future phenotypes for dairy replacement heifers, thereby facilitating culling decisions that can lead to decreased feed costs during the rearing period. For these decisions, prediction of the animal's own phenotype is of greater importance than prediction of the genetic superiority or inferiority that will transmit to its offspring.