Pandemic Racism: Lessons on the Nature, Structures, and Trajectories of Racism During COVID-19

The COVID-19 pandemic has been one of the most acute global crises in recent history, which profoundly impacted the world across many dimensions. During this period, racism manifested in ways specifically related to the pandemic, including xenophobic sentiments, racial attacks, discriminatory policies, and disparate outcomes across racial/ethnic groups. This paper examines some of the pressing questions about pandemic racism and inequity. We review what research has revealed about the nature and manifestations of racism, the entrenchment of structural racism, and trajectories of racism during COVID-19.

Improved dsRNA isolation and purification method validated by viral dsRNA detection using novel primers in Saccharomyces cerevisiae

Accurate genomic sequencing demands high-quality double-stranded RNA (dsRNA). Existing methods for dsRNA extraction from yeast, fungi, and plants primarily rely on cellulose, suitable only for small volume extractions, or the time-consuming lithium chloride precipitation. To streamline the traditional phenol-chloroform-based dsRNA extraction method, the main challenge is the reduction of mitochondrial DNA (mtDNA) and Single Stranded RNA (ssRNA) to no detectable levels after gel electrophoresis. This challenge is successfully addressed through the modified approach described here, involving phenol extraction at low pH, followed by the addition of ammonium sulfate to the aqueous buffer. The dsRNA isolated using this novel method exhibits comparable quality to that obtained through cellulose purification, and it is readily amenable to RT-PCR. Moreover, a single batch of yeast cell RNA isolation requires only 2-3 h of hands-on time, thus simplifying and expediting the process significantly.•Buffers were redesigned from [32,33,35].•No DNASE, Ribonuclease A or beads were used during the purification.•Simple and inexpensive dsRNA extraction and purification method is described.

HOS1 promotes plant tolerance to low-energy stress via the SnRK1 protein kinase

Plants need to integrate internal and environmental signals to mount adequate stress responses. The NUCLEAR PORE COMPLEX (NPC) component HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENES 1 (HOS1) is emerging as such an integrator, affecting responses to cold, heat, light and salinity. Stress conditions often converge in a low-energy signal that activates SUCROSE NON-FERMENTING 1-RELATED KINASE 1 (SnRK1) to promote stress tolerance and survival. Here, we explored the role of HOS1 in the SnRK1-dependent response to low-energy stress in Arabidopsis thaliana, using darkness as a treatment and a combination of genetic, biochemical, and phenotypic assays. We show that the induction of starvation genes and plant tolerance to prolonged darkness are defective in the hos1 mutant. HOS1 interacts physically with the SnRK1α1 catalytic subunit in yeast-two-hybrid and in planta, and the nuclear accumulation of SnRK1α1 is reduced in the hos1 mutant. Likewise, another NPC mutant, nup160, exhibits lower activation of starvation genes and decreased tolerance to prolonged darkness. Importantly, defects in low-energy responses in the hos1 background are rescued by fusing SnRK1α1 to a potent nuclear localization signal, or by sugar supplementation during the dark treatment. Altogether, this work demonstrates the importance of HOS1 for the nuclear accumulation of SnRK1α1, which is key for plant tolerance to low-energy conditions.

Elevated thrombin generation levels in the left atrial appendage in patients with atrial fibrillation

Introduction

Atrial Fibrillation (AF) is the most common sustained arrhythmia. Thrombus formation in the left atrial appendage (LAA) increases the risk for stroke and systemic embolism in AF patients. The proposed mechanisms for thrombus formation in the LAA are stasis, endothelial dysfunction and local hypercoagulability. The aim of this study was to compare thrombin generation potential in various heart chambers among AF patients.

Material and methods

A prospective cross-sectional study of 47 patients with AF undergoing pulmonary vein isolation (PVI). Blood samples from the femoral vein (FV), right atrium (RA), left atrium (LA) and LAA were collected during the PVI procedures. The Samples were collected before heparin administration. Thrombin generation was assessed by the calibrated automated thrombogram (CAT).

Results

A total of 47 patients (36.2% female, mean age 58.7±13, 59.6% with CHADS-VASc ≥2) were enrolled into the study. The mean endogenous thrombin potentials (ETP) were 1580±558, 1433±540, 1141±611 and 1487±760 in the FV, RA, LA and LAA, respectively (P<0.05). The mean thrombin peak heights were 244±124, 199±102, 139±94 and 195±129 in the FV, RA, LA and LAA, respectively (P<0.05).

A post-hoc pairwise comparison demonstrated elevated thrombin generation in the LAA compared to the LA (P=0.014). Furthermore, LA thrombin generation levels were significantly lower from the FV and RA (P<0.05).

Conclusion

In patients with AF, the LAA has increased thrombotic potential compared to the LA. These findings might explain why the LAA is more predisposed to thrombus formation than the LA.

Funding Acknowledgement

Type of funding sources: None.

Serological cross-sectional survey of equine infectious anemia in Saudi Arabia

The equine infectious anaemia virus (EIAV) is one of the most serious equine diseases worldwide. There is scarce information on the epizootiology of equine infectious anaemia (EIA) in Saudi Arabia. Given the importance of the equine industry in Saudi Arabia, this cross- -sectional study aims to provide information about the prevalence of EIAV based on serological surveillance of the equine population in the country. A total of 4728 sera samples were collected (4523 horses and 205 donkeys) between December 2017 and November 2019. All samples were tested using commercially available EIAV ELISA. All tested samples showed negative results for EIAV antibodies with a 95% confidence interval. The results provided evidence that Saudi Arabia's equine populations (horses and donkeys) are currently free of EIAV. The results also suggest the need for continuous monitoring of EIAV and strict regulation when importing horses from other countries.

Is it justified to search for cancer in patients with peripheral arterial disease?

BACKGROUND

Cancer is the leading cause of death in European countries, ahead of cardiovascular diseases. Cancer is also the most common co-morbidity among patients hospitalized for the management of cardiovascular diseases. Through an overview, we searched for the frequency and types of cancer associated with peripheral arterial disease (PAD) in order to address the relevance of cancer screening in patients with PAD.

METHODS

We searched in PubMed database from 1996 to 2020 for retrospective and prospective cohort or cross-sectional or randomized studies evaluating the frequency of all types of cancer in patients with PAD excluding patients with aneurysmal disease. The keywords used were: peripheral arterial disease, arterial thrombosis, acute leg ischemia, critical leg ischemia, chronic leg ischemia, intermittent claudication, malignant tumor, cancer.

RESULTS

Based on published studies, the frequency of cancer in patients with PAD varied widely from 3.8 to 30.4% depending on study design, population, method used to screen for cancer and study period. In medical records database and registers,cancer prevalence varied from 3,8% to 22,4% in 4 retrospective studies of patients with acute limb ischemia and from 10.5 to 30.4% in 3 prospective studies of patients with acute limb ischemia, critical ischemia or intermittent claudication. In 3 retrospective analyses from 2 population-based cohorts and health insurance claims data, incidence of cancer in patients with intermittent claudication, acute limb ischemia or peripheral arterial disease varied from 8% to 11.7%. The frequency of cancer in PAD patients appeared higher than in the general population. Tobacco-dependent cancers seemed to be the most common cancers in PAD. Cancers were also more frequent in case of anemia, amputation and iterative bypass thrombosis in few studies.

CONCLUSION

Although there is no recommendation for cancer screening in patients with PAD, the high prevalence of cancer raises the question of screening patients at high risk such as those with acute or critical limb ischemia and especially in case of severe tobacco use, anemia, amputation and iterative bypass thrombosis. These results call for further studies with larger sample size and long term follow-up.

The composition of the lipid, protein and mineral fractions of quail breast meat obtained from wild and farmed specimens of Common quail (Coturnix coturnix) and farmed Japanese quail (Coturnix japonica domestica)

The present study was intended to answer 2 scientific hypotheses: 1) the quail species has a significant influence in quail breast meat composition; 2) the wild quail's meat presents healthier composition than their farmed counterparts.

An analysis of the pectoral muscles of wild and captive common quails (Coturnix coturnix) and domestic quails (Coturnix japonica domestica) was performed. The content of fatty acids (FA), amino acids, total cholesterol, and vitamin E, some basic macro- and microminerals in the pectoral muscles of the 2 species of the genus Coturnix were analyzed.

Regarding the quail species influence on meat composition, Japanese Quail (JQ) revealed better lipid composition, characterized by lower saturated FA (SFA; less 3.17 g/100 g of total fatty acids), higher polyunsaturated FA contents (PUFA; more 5.5 g/100 g of total fatty acids) and healthier polyunsaturated FA/saturated FA (P/S) and n-6/n-3 ratios and TI value (1.08, 9.54 and 0.60 vs. 0.76, 12.58, and 0.75, correspondingly). The absence of differences observed on amino acids partial sums and ratios reveals equality between species on protein nutritional quality. On the other hand, Common Quail (CQ) proved to be a better source of copper (0.181 mg/100 g of meat), iron (2.757 mg/100 g of meat), manganese (0.020 mg/100 g of meat), and zinc (0.093 mg/100 g of meat) than JQ.

The comparison of farmed and wild specimens within CQ, showed that wild birds presented lower total cholesterol (less 8.32 mg/g of fresh meat) and total PUFA (less 4.26 g/100 g of total fatty acids), and higher n-3 PUFA contents (more 1.53 g/100 g of total fatty acids), which contributed to healthier P/S and n-6/n-3 ratios, but worst PI (1.60, 8.08, and 113.1 vs. 0.76, 12.58, and 100.8, respectively). The wild species revealed higher α-tocopherol content (2.40 vs. 1.49 µg/g of fresh meat. Differences observed on their mineral composition counterbalance each other.

Under intensive production system and similar feeding and management conditions, the CQ develops better nutritional qualities than JQ. The comparison of wild and farmed species within CQ reveals more similarities than differences. Quail´s meat presents good nutritional quality and introduces variability to human's diet, which is much valued by consumers.

Current-limiting amplifier for high speed measurement of resistive switching data

Resistive switching devices, important for emerging memory and neuromorphic applications, face significant challenges related to the control of delicate filamentary states in the oxide material. As a device switches, its rapid conductivity change is involved in a positive feedback process that would lead to runaway destruction of the cell without current, voltage, or energy limitation. Typically, cells are directly patterned on MOS transistors to limit the current, but this approach is very restrictive as the necessary integration limits the materials available as well as the fabrication cycle time. In this article, we propose an external circuit to cycle resistive memory cells, capturing the full transfer curves while driving the cells in a way that suppresses runaway transitions. Using this circuit, we demonstrate the acquisition of 10⁵ I, V loops per second without using on-wafer current limiting transistors. This setup brings voltage sweeping measurements to a relevant timescale for applications and enables many new experimental possibilities for device evaluation in a statistical context.

Pneumococcal and meningococcal vaccines - A significant reduction of pediatric admissions and deaths

Background

Mortality rates associated with paediatric inpatient stays in mainland Portuguese Hospitals have decreased approximately 50%, between 2000 and 2016, despite the majority of deaths occurring in hospitals. During this timeframe meningococcal and pneumococcal vaccines were introduced in the National Vaccination Programme (NVP). In this study, the authors analyzed admission and mortality rates associated with vaccine preventable diseases such as pneumococcal and meningococcal disease.

Methods

A sequential cross-sectional retrospective study was performed, from 2000 and 2016, to assess the hospitalizations for meningitis, sepsis and pneumonia of children and adolescents at the SNS (National Health Service) hospitals in mainland Portugal. An administrative Portuguese database that contains all the public hospital admissions to mainland Portugal hospitals was utilized and diagnoses were coded per ICD9. National Institute Of Statistics (INE) data was accessed as reference. All admissions of individuals 17 years old and younger were analysed.

Results

A 10-fold reduction of admissions and deaths for pneumococcal pneumonia and a 3-fold reduction of meningococcal sepsis were observed after the introduction of the antipneumococcal and antimeningococcal vaccine in the NVP, respectively.

Conclusions

These results highlight the importance of vaccination to prevent illness, hospital admissions and deaths in children and can provide evidence to educate the public towards vaccination.

Key messages

The results highlight the importance of vaccination to prevent illness, hospital admissions and deaths in children. The results show a 10x reduction in pneumococcal pneumonia hospital admission and deaths and a 3x in meningococcal meningitis.

SAT0152 EFFICACY OF BARICITINIB IN PATIENTS WITH MODERATE-TO-SEVERE RHEUMATOID ARTHRITIS WITH 3 YEARS OF TREATMENT: RESULTS FROM A LONG-TERM STUDY

Background:

Baricitinib (Bari) is an oral, selective and reversible Janus kinase 1 and 2 inhibitor approved for the treatment of adults with active RA. In addition to long-term safety which has been disclosed previously with data up to 7 years [1], an important clinical consideration is whether treatment efficacy can be maintained over the long term.

Objectives:

To evaluate the long-term efficacy of once-daily Bari 4 mg in patients with active rheumatoid arthritis (RA) who were either naïve to or who had inadequate response (IR) to methotrexate (MTX)

Methods:

Post hoc analyses of data from two phase 3 studies, RA-BEGIN (MTX-naïve) and RA-BEAM (MTX-IR) for 52 weeks, and one long-term extension (LTE) study (RA-BEYOND) for an additional 96 weeks were conducted (148 weeks in total). At week 52, MTX-naïve patients initially treated with MTX monotherapy, Bari 4 mg monotherapy, or Bari 4 mg +MTX in RA-BEGIN were switched to open-label Bari 4 mg monotherapy for treatment in the LTE. Similarly, at week 52, MTX-IR patients initially treated with Bari 4 mg [+ background MTX noted as (+MTX) for RA-BEAM] or adalimumab (ADA) (+MTX) in RA-BEAM were switched to open-label Bari 4 mg (+MTX) for treatment in the LTE. Patients who received placebo (+MTX) were switched to open-label Bari 4 mg (+MTX) at week 24. The analyses of efficacy (SDAI) and physical function (HAQ-DI) were conducted on all patients who were randomized into the RA-BEGIN and RA-BEAM studies and had received ≥1 dose of study drug after randomization (mITT population). The proportion of patients who reached low disease activity (LDA), as measured by SDAI ≤11, was evaluated along with change from baseline in HAQ-DI. The non-responder imputation (NRI) method was used for the categorical analysis.

Results:

By week 24 in RA-BEGIN (N=584), 62% of patients treated with Bari 4 mg monotherapy or Bari 4 mg +MTX achieved SDAI LDA in comparison to 40% of pts in the MTX monotherapy group; response rates seen at week 24 in the Bari treatment groups were maintained through week 148 (Fig 1A). Similarly, by week 24 in RA-BEAM (N=1,305), 52% of patients treated with Bari 4 mg (+MTX) and 50% of patients treated with ADA (+MTX) achieved a SDAI LDA in comparison to 26% of patients from the PBO (+MTX) group. The response rate seen at week 24 with Bari 4 mg and ADA were maintained through week 148, even after patients switched from ADA to Bari 4 mg at week 52 (Fig 1B). Similar improvement and maintenance patterns in physical function measured by HAQ-DI were demonstrated. The overall discontinuation rate across treatment groups from RA-BEGIN (19.5%) and RA-BEAM (14.2%) have been published. In the LTE, the discontinuation rate from Bari treatment was 13.7% for patients originating from RA-BEGIN (1.1% due to lack of efficacy, 6.4% due to safety) and 12.6% for patients originating from RA-BEAM (1.8% due to lack of efficacy, 5.9% due to safety).

Figure 1.

Proportion of patients achieving SDAI ≤11 in the NRI analysis†In RA-BEGIN, rescue to Bari 4 mg + MTX was offered at week 24.‡In RA-BEAM, rescue to Bari 4 mg (+ MTX) was offered at week 16. At week 24, all PBO + MTX patients were switched to Bari 4 mg + MTX.§Upon entering RA-BEYOND at week 52, MTX and ADA patients were switched to Bari 4 mg.

Conclusion:

Long-term treatment with Bari 4 mg demonstrated the maintenance of clinically-relevant outcomes for up to 3 years. Low discontinuation rates during the LTE indicated that Bari 4 mg treatment was well-tolerated.

References:

[1]Genovese et al.Annals of the Rheumatic Diseases. 2019;78:308-309.

Disclosure of Interests: :

Josef S. Smolen Grant/research support from: AbbVie, AstraZeneca, Celgene, Celltrion, Chugai, Eli Lilly, Gilead, ILTOO, Janssen, Novartis-Sandoz, Pfizer Inc, Samsung, Sanofi, Consultant of: AbbVie, AstraZeneca, Celgene, Celltrion, Chugai, Eli Lilly, Gilead, ILTOO, Janssen, Novartis-Sandoz, Pfizer Inc, Samsung, Sanofi, Li Xie Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Bochao Jia Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Peter C. Taylor Grant/research support from: Celgene, Eli Lilly and Company, Galapagos, and Gilead, Consultant of: AbbVie, Biogen, Eli Lilly and Company, Fresenius, Galapagos, Gilead, GlaxoSmithKline, Janssen, Nordic Pharma, Pfizer Roche, and UCB, Gerd Rüdiger Burmester Consultant of: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Speakers bureau: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin, Ayesha Elias Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Anabela Cardoso Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Robert Ortmann Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Chad Walls Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Maxime Dougados Grant/research support from: AbbVie, Eli Lilly, Merck, Novartis, Pfizer and UCB Pharma, Consultant of: AbbVie, Eli Lilly, Merck, Novartis, Pfizer and UCB Pharma, Speakers bureau: AbbVie, Eli Lilly, Merck, Novartis, Pfizer and UCB Pharma

Efficacy and tolerability of trabectedin in elderly patients with sarcoma: subgroup analysis from a phase III, randomized controlled study of trabectedin or dacarbazine in patients with advanced liposarcoma or leiomyosarcoma

Background

Treatment options for soft tissue sarcoma (STS) patients aged ≥65 years (elderly) can be limited by concerns regarding the increased risk of toxicity associated with standard systemic therapies. Trabectedin has demonstrated improved disease control in a phase III trial (ET743-SAR-3007) of patients with advanced liposarcoma or leiomyosarcoma after failure of anthracycline-based chemotherapy. Since previous retrospective analyses have suggested that trabectedin has similar safety and efficacy outcomes regardless of patient age, we carried out a subgroup analysis of the safety and efficacy observed in elderly patients enrolled in this trial.

Patients and methods

Patients were randomized 2 : 1 to trabectedin (n = 384) or dacarbazine (n = 193) administered intravenously every-3-weeks. The primary end point was overall survival (OS); secondary end points were progression-free survival (PFS), time-to-progression, objective response rate (ORR), duration of response, symptom severity, and safety. A post hoc analysis was conducted in the elderly patient subgroup.

Results

Among 131 (trabectedin = 94; dacarbazine = 37) elderly patients, disease characteristics were well-balanced and consistent with those of the total study population. Treatment exposure was longer in patients treated with trabectedin versus dacarbazine (median four versus two cycles, respectively), with a significantly higher proportion receiving prolonged therapy (≥6 cycles) in the trabectedin arm (43% versus 23%, respectively; P = 0.04). Elderly patients treated with trabectedin showed significantly improved PFS [4.9 versus 1.5 months, respectively; hazard ratio (HR)=0.40; P = 0.0002] but no statistically significant improvement in OS (15.1 versus 8.0 months, respectively; HR = 0.72; P = 0.18) or ORR (9% versus 3%, respectively; P = 0.43). The safety profile for elderly trabectedin-treated patients was comparable to that of the overall trabectedin-treated study population.

Conclusions

This subgroup analysis of the elderly population of ET743-SAR-3007 suggests that elderly patients with STS and good performance status can expect clinical benefit from trabectedin similar to that observed in younger patients.

Trial registration

www.clinicaltrials.gov, NCT01343277.

Abstract P5-05-05: Targeting the androgen receptor with seviteronel, a CYP17 lyase and AR inhibitor, in triple negative breast cancer

Background: Androgen receptor (AR) protein is expressed across breast cancer (BC) subtypes, including up to 50% of triple negative breast cancers (TNBC) and it is often maintained in metastases. Our research demonstrated that TNBC cell lines rely on increased AR for anchorage independent survival, mammosphere formation, tumor initiation, and other stem-cell like properties. Further, AR mRNA levels increased in circulating tumor cells in the blood as compared to levels in the primary tumors of mice harboring human patient derived xenografts (PDX). Seviteronel (SEVI), a CYP17 lyase and AR inhibitor that blocks androgen and estrogen biosynthesis and AR activation, is in phase 2 clinical development for men and women with AR+ solid tumors, including advanced BC and has clinical activity in both basal and LAR subtypes (Innocrin data on file).

Hypothesis: We hypothesized that targeting both androgen biosynthesis and AR activation with an agent such as SEVI would decrease tumor growth in preclinical models of AR+ TNBC.

Methods: Genes regulated by AR under anchorage independent conditions with and without 10 nM dihydrotestosterone (DHT) were identified by AR chromatin immunoprecipitation (ChIP)-seq, RNA-seq, and Ingenuity Pathway Analysis. In vitro activity of SEVI was assayed in AR+ TNBC cell lines (MDA-MB-453 and SUM159). The IC50 of SEVI was determined via crystal violet. Soft agar colony formation assays and growth on poly-HEMA coated plates measured anchorage independent growth. In vivo, an AR+ TNBC patient derived xenograft (HCI-009, generated by Dr. Alana Welm) was grown in NSG mice given either DHT vs. vehicle control or, in a separate experiment, SEVI (150 mg/kg/day PO) vs. vehicle control.

Results: ChIP-seq and RNA-seq in MDA-MB-453 demonstrated that AR chromatin binding and gene regulation increased under anchorage independent conditions in a ligand dependent manner and showed an increase in mTOR signaling, aryl hydrocarbon receptor signaling and metabolism. SEVI inhibited proliferation of AR+ TNBC in a dose-dependent manner and growth on soft agar. In vivo, the AR+ TNBC HCI-009 PDX exhibited a significant increase in tumor volume with DHT indicating AR dependence. SEVI treatment also decreased HCI-009 tumor volume (p=0.0054) and rate of growth (p=0.0146). Nuclear AR protein and classical AR-regulated genes such as KLK3 and FKBP5 were increased with DHT in the HCI-009 xenograft tumors and decreased in mice treated with SEVI and were confirmed at the protein level.

Conclusion: These results further demonstrate the activity of SEVI, a CYP17 lyase and AR inhibitor, in preclinical models of AR+ TNBC. Use of AR targeting agents may be a rational treatment approach for a subset of patients with AR+ TNBC since such tumors may respond less well to chemotherapy than other TNBC molecular subtypes. We continue to identify markers of AR dependence/responsiveness to AR-targeted therapy.

Citation Format: Reese JM, Babbs BL, Christenson JL, Spoelstra NS, Elias A, Eisner JR, Baskin-Bey ES, Gertz J, Richer JK. Targeting the androgen receptor with seviteronel, a CYP17 lyase and AR inhibitor, in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-05-05.

Abstract P1-15-02: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Schwab R, Clark A, Yau C, Wolf D, Chien AJ, Majure M, Ewing C, Wallace A, Roesch E, Helsten T, Forero A, Stringer-Reasor E, Vaklavas C, Nanda R, Jaskowiak N, Boughey J, Haddad T, Han H, Lee C, Albain K, Isaacs C, Elias A, Ellis E, Shah P, Lang J, Lu J, Tripathy D, Kemmer K, Yee D, Haley B, Korde L, Edmiston K, Northfelt D, Viscusi R, Khan Q, I-SPY 2 Consortium, Symmans WF, Perlmutter J, Hylton N, Rugo H, Melisko M, Wilson A, Singhrao R, Asare S, van't Veer L, DeMichele A, Berry D, Esserman L. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-15-02.

D-Dimer Test and Diagnosis of Deep Vein Thrombosis: A Comparative Study of 7 Assays

The current D-Dimer ELISA methods provide high sensitivity and negative predictive value for the diagnosis of deep vein thrombosis but these methods are not suitable for emergency or for individual determination. We have evaluated the performance of 3 newly available fast D-Dimer assays (Vidas D-Di, BioMerieux; Instant IA D-Di, Stago; Nycocard D-Dimer, Nycomed) in comparison with 3 classic ELISA methods (Stago, Organon, Behring) and a Latex agglutination technique (Stago). One-hundred-and-seventy-one patients suspected of presenting a first episode of deep vein thrombosis were investigated. A deep vein thrombosis was detected in 75 patients (43.8%) by ultrasonic duplex scanning of the lower limbs; in 11 of them the thrombi were distal and very limited in size (<2 cm). We compared the performance of the tests by calculating their sensitivity, specificity, positive and negative predictive value for different cut-off levels and by calculating the area under ROC curves. The concordance of the different methods was evaluated by calculating the kappa coefficient. The performances of the 3 classic ELISA and of the Vidas D-Di were comparable and kappa coefficients indicated a good concordance between the results provided by these assays. Their sensitivity slightly declined for detection of the very small thrombi. Instant IA D-Di had a non-significantly lower sensitivity and negative predictive value than the 4 previous assays; however its performance was excellent for out-patients. As expected, the Latex assay had too low a sensitivity and negative predictive value to be recommended. In our hands, Nycocard D-Dimer also exhibited low sensitivity and negative predictive value, which were significantly improved when the plasma samples were tested by the manufacturer. Thus significant progress has been made, allowing clinical studies to be planned to compare the safety and cost-effectiveness of D-Dimer strategy to those of the conventional methods for the diagnosis of venous thrombosis.

Predicting Daily Maintenance Dose of Fluindione, an Oral Anticoagulant Drug

Due to large inter-individual variations, the dose of vitamin K antagonist required to target the desired hypocoagulability is hardly predictible for a given patient, and the time needed to reach therapeutic equilibrium may be excessively long. This work reports on a simple method for predicting the daily maintenance dose of fluindione after the third intake. In a first step, 37 patients were delivered 20 mg of fluindione once a day, at 6 p.m. for 3 consecutive days. On the morning of the 4th day an INR was performed. During the following days the dose was adjusted to target an INR between 2 and 3. There was a good correlation (r = 0.83, p<0.001) between the INR performed on the morning of day 4 and the daily maintenance dose determined later by successive approximations. This allowed us to write a decisional algorithm to predict the effective maintenance dose of fluindione from the INR performed on day 4. The usefulness and the safety of this approach was tested in a second prospective study on 46 patients receiving fluindione according to the same initial scheme. The predicted dose was compared to the effective dose soon after having reached the equilibrium, then 30 and 90 days after. To within 5 mg (one quarter of a tablet), the predicted dose was the effective dose in 98%, 86% and 81% of the patients at the 3 times respectively. The mean time needed to reach the therapeutic equilibrium was reduced from 13 days in the first study to 6 days in the second study. No hemorrhagic complication occurred. Thus the strategy formerly developed to predict the daily maintenance dose of warfarin from the prothrombin time ratio or the thrombotest performed 3 days after starting the treatment may also be applied to fluindione and the INR measurement.

Influence of Long Term Oral Anticoagulants upon Prothrombin Fragment 1 + 2, Thrombin-Antithrombin III Complex and D-Dimer Levels in Patients Affected by Proximal Deep Vein Thrombosis

We have investigated the influence of long term oral anticoagulants (OAC) upon the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), of thrombin-antithrombin III complexes (TAT) and of D-Dimer in 20 patients affected by a proximal deep vein thrombosis (DVT) diagnosed by ultrasonic duplex scanning. Patients (63 ± 17 years, mean ± SD) were sampled at the beginning of the OAC treatment (day 1), which was started 1 to 6 days after diagnosis confirmation and full heparinization, and then 8, 35 and 92 days after. The results were compared to those obtained in a blood donor population (39 ± 10 years) and to an age-matched healthy population (63 ± 19 years). The mean INR determined on days 8, 35 and 92 were almost identical (2.8 ± 0.7, 2.9 ± 0.9 and 2.8 ± 0.6 respectively). In contrast, highly significant variations of the three markers were recorded during the observation period. Eight days after the beginning of OAC, increased levels of TAT complexes were associated with subnormal levels of F1 + 2 suggesting persistence of a hypercoagulable state. On the further sampling times, TAT complexes were in the normal range while F1 + 2 were far below the normal range. Between day 1 and day 92, the levels of D-Dimer continuously decreased reflecting a long-term fibrinolytic process.

This study clearly indicates that high INR are not systematically associated with very low F1 + 2 levels, particularly in the acute phase of thrombosis. Whether or not it is possible to reduce the intensity of the anticoagulant treatment 1 month after its initiation on the basis of very low levels of F1 + 2 can only be determined by prospective clinical trials.

Abstract P4-09-09: Correlation of breast cancer index (BCI) predictive (HoxB13/IL17BR) results to nodal status and hormone receptor expression in early stage HR+ breast cancer

Background: The HoxB13/IL17BR (H/I) ratio, the endocrine response component of the Breast Cancer Index (BCI), was initially discovered in patients with LN- breast cancer, and validated as a predictive biomarker of benefit from extended endocrine therapy (EET) in a cohort from MA.17 that included both LN- and LN+ patients. Here, correlative analyses were performed to further characterize BCI Predictive (H/I) results with nodal status and quantitative hormone receptor expression.

Methods: Analyses were performed using data from the BCI Clinical Database for Correlative Studies, an IRB-approved de-identified database that contains &gt;50 clinicopathologic and molecular variables from cases submitted for BCI in clinical practice (N=19,126). Clinicopathologic variables were abstracted from pathology reports, and were available for a subset of these cases. Cases from patients with confirmed nodal status were analyzed. Chi-squared tests and ANOVA were used to compare results between subgroups.

Results: Analyses included 13,114 patients (median age 58.9y; range 23-92y); 9562 were LN- and 3552 LN+. The distribution of individual H/I scores and proportion of patients classified as High H/I were generally similar in LN- and LN+ patients, though a modestly greater proportion of LN+ patients (46.2%) were classified as High H/I compared to LN- patients (42.0%; P&lt;0.01). In both LN- and LN+ patients, median quantitative ER (qER) expression was slightly higher in patients with Low H/I than with High H/I; qPR showed the same trend but with a larger magnitude (P&lt;0.0001 for both). Similar results were observed for percent positive staining by IHC (P&lt;0.0001). In both LN- and LN+ patients, H/I showed a weak negative correlation with qER (LN-, 0.227; LN+, 0.192) and qPR expression (LN-, 0.311; LN+, 0.311).

Conclusion: In this study to evaluate potential biological correlates of BCI, results showed that H/I biomarker activity did not appear to be dependent on nodal status. Secondly, although ER expression is an established biomarker for endocrine sensitivity, High H/I status did not correlate with increased quantitative ER and PR expression. The H/I ratio may be an independent new marker for endocrine sensitivity independent of the strength of ER expression.

Citation Format: Elias A, Israel MA, Zhang Y, Schnabel CA, Mayordomo J. Correlation of breast cancer index (BCI) predictive (HoxB13/IL17BR) results to nodal status and hormone receptor expression in early stage HR+ breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-09-09.

Abstract P1-07-12: Correlation of breast cancer index (BCI) prognostic and predictive results to clinicopathologic risk groups in early stage HR+ breast cancer

Background: Both clinicopathologic factors and genomic tests have been shown to be prognostic for risk of late distant recurrence (DR); however, few studies have characterized differential patient stratification.Breast Cancer Index (BCI) is a validated gene expression assay for patients with early-stage HR+ breast cancer that provides a prognostic result for high vs low risk of late distant recurrence and a separate predictive result (based on the HoxB13/IL17BR [H/I] ratio) for high vs low likelihood of benefit from extended endocrine therapy. Thus four categories of results are possible based on a patient's tumor biology. To better understand how patient stratification is affected by a combination of clinicopathologic and genomic factors, this study examined BCI assay results within clinicopathologic risk categories based on tumor size and grade.

Methods: This study utilized data from the BCI Clinical Database for Correlative Studies, an IRB-approved de-identified database which contains clinicopathologic and molecular variables from 19,126 clinical cases submitted for BCI testing. Clinicopathologic variables, abstracted from pathology reports, were available for a subset of these cases. This analysis evaluated cases from LN- patients with available clinicopathologic data. Chi-squared tests were used to compare BCI results between tumor size and grade subgroups.

Results: Analyses included 3843 LN- patients (median age 59.1y; range 26-89y; 74% ≥50y), of which 31%, 52%, 17% were Grade 1, 2, and 3, respectively, and 5%, 22.7%, 48.9%, 21.7%, and 1.6% were T1mi/a, T1b, T1c, T2, and T3, respectively. In analysis based on tumor size, there was a wide distribution of individual BCI Prognostic scores in all tumor size subsets; however, the proportion of patients classified as high risk increased with larger tumor size (T1a/b 39.0%, T1c 50.1%, T2 61.0%; p&lt;.0001). In contrast, BCI Predictive (H/I) was not as strongly correlated with size, with a modestly larger proportion of patients classified as High H/I with larger tumor size (T1a/b 37.2%, T1c 40.5%, and T2 45.3%; p=.005). Within each tumor size category, the proportion of patients classified as BCI High Risk and High H/I increased with tumor grade (p&lt;.0001). However, there was a wide distribution of individual risk assessments by BCI Prognostic and stratification by BCI Predictive (H/I) in all size + grade subsets. In patients with the most favorable clinicopathologic risk profile (T1a/b, G1), BCI classified 20% as high risk, 68% of whom also had High H/I.

Conclusion: While BCI results correlated with tumor size and grade, BCI identified substantial proportions of patients with favorable clinicopathologic features as high risk for late DR and apparent high likelihood of benefit from EET; conversely, BCI also identified patients with high risk clinicopathologic features as low risk for late distant recurrence and apparent low likelihood of benefit from EET. These findings help to differentiate between genomic-based and clinicopathologic-based risk/benefit assessment for patients considering EET.

Citation Format: Mayordomo J, Falkson C, Kepes J, Israel MA, Schroeder BE, Schnabel CA, Elias A. Correlation of breast cancer index (BCI) prognostic and predictive results to clinicopathologic risk groups in early stage HR+ breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-07-12.

Prevalence of and factors associated with burnout among health care professionals in Arab countries: a systematic review

BACKGROUND

Burnout among healthcare professionals is one of the key challenges affecting health care practice and quality of care. This systematic review aims to (1) estimate the prevalence of burnout among health care professionals (HCP) in Arab countries; and (2) explore individual and work-related factors associated with burnout in this population.

METHODS

Multiple electronic databases were searched for studies published in English or Arabic from January 1980 to November 2014 assessing burnout (using the Maslach Burnout Inventory; MBI) amongst health care professionals (HCP) in Arab countries.

RESULTS

Nineteen studies (N = 4108; 49.3% females) conducted on HCP in Bahrain, Egypt, Jordan, Lebanon, Palestine, Saudi Arabia and Yemen were included in this review. There was a wide range of prevalence estimates for the three MBI subscales, high Emotional Exhaustion (20.0-81.0%), high Depersonalization (9.2-80.0%), and low Personal Accomplishment (13.3-85.8%). Gender, nationality, service duration, working hours, and shift patterns were all significantly associated with burnout.

CONCLUSIONS

Within the constraints of the study and the range of quality papers available, our review revealed moderate-to-high estimates of self-reported burnout among HCP in Arab countries that are similar to prevalence estimates in non-Arabic speaking westernized developed countries. In order to develop culturally appropriate interventions, further research using longitudinal designs is needed to confirm the risk factors for burnout in specific HCP settings and specialties in Arab countries.

Psychometric Properties of the Malay Language Version of Knee Injury and Osteoarthritis Outcome Score (KOOS) Questionnaire among Knee Osteoarthritis Patients: A Confirmatory Factor Analysis

Introduction: This study aimed to cross-culturally adapt a Malay version of Knee Injury and Osteoarthritis Outcome Score (KOOS) and to evaluate its psychometric properties in patients with knee osteoarthritis (OA).

Materials and Methods: The English version KOOS was translated into a Malay version using forward and backward translation process, followed by face validity and content validity. Two hundred and twenty-six knee OA patients attending the Outpatient and Orthopaedic Clinics, Universiti Sains Malaysia Hospital, completed the Malay version KOOS. Construct validity using confirmatory factor analysis and internal reliability assessment were performed.

Results: The results showed that the original five-factor model with 42 items failed to achieve acceptable values of the goodness of fit indices, indicating poor model fit. A new five-factor model of 26 items demonstrated acceptable level of goodness of fit (comparative fit index= 0.929, incremental fit index= 0.930, Tucker Lewis fit index= 0.920, root mean square error of approximation= 0.073 and Chisquared/degree of freedom= 2.183) indices to signify a model fit. The Cronbach’s alpha value for the new model ranged from 0.776 to 0.946. The composite reliability values of each construct ranged between 0.819 and 0.921, indicating satisfactory to high level of convergent validity.

Conclusion: The five-factor model with 26 items in the Malay version of KOOS questionnaire demonstrated a good degree of goodness of fit and was found to be valid, reliable and simple as an assessment tool for symptoms, pain, activity of daily living, sports and recreational activity and quality of life for Malaysian adults suffering from knee osteoarthritis.

Site promiscuity of coliphage HK022 integrase as a tool for gene therapy

The integrase (Int) encoded by the lambdoid coliphage HK022 targets in its host chromosome a 21 base pair (bp) recombination site termed attB or BOB'. attB comprises two 7 bp partially inverted (palindromic) Int-binding sites of 7 bp each termed B and B'. B and B' flank a central 7 bp crossover site or 'overlap' (O). We show that replacing O with a random 7 bp sequence supports Int-mediated site-specific recombination as long as the cognate and larger phage recombination site attP features an identical O sequence. This promiscuity allowed us to identify on the human genome several native active secondary attB sites ('attB') with random overlaps that flank human deleterious mutations, raising the prospect of using such sites to cure the 'attB'-flanked mutations by Int-catalyzed RMCE (recombinase-mediated cassette exchange) reactions. An analysis of such active and inactive 'attB's suggested a minimal 14-15 bp attB consensus sequence (instead of the 21 bp) with a reduced 3 bp palindrome.

A hybrid biological process of indoor air treatment for toluene removal

Bioprocesses, such as biofiltration, are commonly used to treat industrial effluents containing volatile organic compounds (VOCs) at low concentrations. Nevertheless, the use of biofiltration for indoor air pollution (IAP) treatment requires adjustments depending on specific indoor environments. Therefore, this study focuses on the convenience of a hybrid biological process for IAP treatment. A biofiltration reactor using a green waste compost was combined with an adsorption column filled with activated carbon (AC). This system treated a toluene-micropolluted effluent (concentration between 17 and 52 μg/m3), exhibiting concentration peaks close to 733 μg/m3 for a few hours per day. High removal efficiency was obtained despite changes in toluene inlet load (from 4.2 x 10(-3) to 0.20 g/m3/hr), which proves the hybrid system's effectiveness. In fact, during unexpected concentration changes, the efficiency of the biofilter is greatly decreased, but the adsorption column maintains the high efficiency of the entire process (removal efficiency [RE] close to 100%). Moreover, the adsorption column after biofiltration is able to deal with the problem of the emission of particles and/or microorganisms from the biofilter. Implications: Indoor air pollution is nowadays recognized as major environmental and health issue. This original study investigates the performance of a hybrid biological process combining a biofilter and an adsorption column for removal of indoor VOCs, specifically toluene.

Accelerated ageing of an EAF black slag by carbonation and percolation for long-term behaviour assessment

The efficient reuse of industrial by-products, such as the electric arc furnace (EAF) black slag, is still hindered by concern over their long-term behaviour in outdoor environments. The aim of this study was to develop an accelerated ageing method to simulate the long-term natural carbonation of EAF slag exposed to the elements. The degree of carbonation achieved in a freshly produced slag after accelerated ageing and in a slag used on a fifteen-year-old unpaved road was very similar. The influence of particle size on accelerated carbonation was assessed, with it being concluded that the slag sample with a particle size bigger than 5-6 mm underwent slight carbonation over time when it was exposed to CO2. The accelerated ageing procedure based on percolating a previously carbonated water solution through the slag column allowed gradual leaching with simulated acid rain, as well as providing information about the gradual and total chemical release from the slag. Three classification groups were established according to the release rate of the determined elements. The joint use of the accelerated carbonation method and the percolation test is proposed as a useful tool for environmental risk assessment concerning the long-term air exposure of EAF black slag.

Abstract P4-12-09: Results from a phase 2a study of trastuzumab emtansine, paclitaxel, and pertuzumab in patients with HER2-positive metastatic breast cancer

Introduction

The antibody-drug conjugate trastuzumab emtansine (T-DM1) combines the antitumor properties of trastuzumab (H) with the cytotoxic agent DM1 via a stable linker. T-DM1 prolonged PFS and OS vs standard therapy in a phase 3 study of patients (pts) with HER2-positive metastatic breast cancer (MBC) previously treated with H and a taxane. Preclinical data suggest synergy when T-DM1 is combined with paclitaxel (T) or pertuzumab (P). In the phase 1b study TDM4652g, the maximum tolerated doses of T-DM1 + T ± P were defined. Here we present results from the phase 2a expansion, which further explored feasibility and safety.

Methods

TDM4652g is a phase 1b/2a open-label study of pts with HER2-positive locally advanced or MBC. Pts had no prior T-DM1 or P, no baseline peripheral neuropathy (PN; phase 2a only), and had LVEF ≥50%. Pts in phase 2a were randomized to T-DM1 3.6 mg/kg q3w + T 80 mg/m2 qw ± P 840 mg loading dose [LD], then 420 mg q3w. The primary objective, feasibility, was assessed by the percent of evaluable pts receiving ≥12 doses of T within 15 weeks of cycle 1, day 1, and those receiving 12 consecutive weeks of T.

Results

Forty-four pts were enrolled (T-DM1 + T, n = 22; T-DM1 + T + P, n = 22); the data snapshot date was May 23, 2013. Median age was 52.5 years (range, 35–81); median number of prior agents for MBC was 6 (range, 0–12). 43 (98%) pts had previously received H, and 36 (82%) pts had received taxane therapy. Median dose intensities were T-DM1, 94% (range 54–105); T, 50% (range 9–100) and P, 100% (range 67–100). 2 pts were not evaluable for feasibility (progressive disease [PD] before receiving 12 doses of T). 21/42 (50%) pts received ≥12 doses of T within 15 weeks; 6/42 (14%) pts received 12 consecutive doses by week 12, and 33/42 (79%) pts received ≥8 doses within 12 weeks. Grade 3/4 adverse events (AEs) were reported for 18 (82%) and 17 (77%) pts in the T-DM1 + T and T-DM1 + T + P groups, respectively (see Table for AEs and best responses). Ten pts discontinued early due to PD (n = 6), PD-related death (n = 2), AEs (n = 1), or withdrawal from the study (n = 1). 21 pts discontinued T due to AEs, most commonly PN (n = 12).

Grade 3/4 AEs occurring in &gt;1 patientAE, n (%)All patients (N = 44)TDM1 3.6 mg/kg q3w + T 80 mg/m2 qw (n = 22)TDM1 3.6 mg/kg q3w + T 80 mg/m2 qw + P 840 mg LD, 420 mg q3w (n = 22)Neutropenia10 (23)6 (27)4 (18)Peripheral neuropathy9 (20)3 (14)6 (27)Fatigue6 (14)3 (14)3 (14)Thrombocytopenia6 (14)5 (23)1 (5)Anemia3 (7)2 (9)1 (5)Abdominal pain2 (5)2 (9)0Decreased hemoglobin2 (5)1 (5)1 (5)Muscosal inflammation2 (5)1 (5)1 (5)Muscular weakness2 (5)02 (9)Nausea2 (5)1 (5)1 (5)Best response,* n (%)CR2 (5)1 (5)1 (5)CR confirmed1 (2)1 (5)0PR27 (61)13 (59)14 (64)PR confirmed8 (18)3 (14)5 (23)SD10 (23)6 (27)4 (18)PD3 (7)1 (5)2 (9)*At any time point with responses ordered CR&gt;PR&gt;SD&gt;PD.

Conclusions

Overall, 50% of pts received ≥12 doses of T within 15 weeks. Adding P to the combination of T-DM1 + T did not appear to increase the incidence of grade 3/4 AEs. Data support further investigation of T-DM1 + T ± P in larger studies in early breast cancer. Final data from all phase 2a patients will be available for the full report.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-09.

ABI1 and PP2CA phosphatases are negative regulators of Snf1-related protein kinase1 signaling in Arabidopsis

Plant survival under environmental stress requires the integration of multiple signaling pathways into a coordinated response, but the molecular mechanisms underlying this integration are poorly understood. Stress-derived energy deprivation activates the Snf1-related protein kinases1 (SnRK1s), triggering a vast transcriptional and metabolic reprogramming that restores homeostasis and promotes tolerance to adverse conditions. Here, we show that two clade A type 2C protein phosphatases (PP2Cs), established repressors of the abscisic acid (ABA) hormonal pathway, interact with the SnRK1 catalytic subunit causing its dephosphorylation and inactivation. Accordingly, SnRK1 repression is abrogated in double and quadruple pp2c knockout mutants, provoking, similarly to SnRK1 overexpression, sugar hypersensitivity during early seedling development. Reporter gene assays and SnRK1 target gene expression analyses further demonstrate that PP2C inhibition by ABA results in SnRK1 activation, promoting SnRK1 signaling during stress and once the energy deficit subsides. Consistent with this, SnRK1 and ABA induce largely overlapping transcriptional responses. Hence, the PP2C hub allows the coordinated activation of ABA and energy signaling, strengthening the stress response through the cooperation of two key and complementary pathways.

Monocyte-macrophage membrane possesses free radicals scavenging activity: stimulation by polyphenols or by paraoxonase 1 (PON1)

In the current study, we analysed free radicals scavenging activity of monocytes-macrophages in the absence or presence of antioxidants such as polyphenols or paraoxonase 1 (PON1). THP-1 human monocytic cell line, murine J774A.1 macrophages, as well as human primary monocytes have the capability to scavenge free radicals, as measured by the 1-diphenyl-2-picryl-hydrazyl (DPPH) assay. This effect (which could be attributed to the cell's membrane) was cell number and incubation time dependent. Upon incubation of J774A.1 macrophages with acetylated LDL (Ac-LDL), with VLDL, or with the radical generator, AAPH, the cells' lipid peroxides content, and paraoxonase 2 (PON2) activity were significantly increased. While non-treated cells decreased DPPH absorbance by 65%, the Ac-LDL-, VLDL- or AAPH-treated cells, decreased it by only 33%, 30%, or 45%, respectively. We next analysed the effect of J774A.1 macrophage enrichment with antioxidants, such as polyphenols or PON1 on the cells' free radicals scavenging activity. Non-treated cells decreased DPPH absorbance by 50%, whereas vitamin E-, punicalagin- or PJ-treated cells significantly further decreased it, by 75%. Similarly, in PON1-treated cells DPPH absorbance was further decreased by 63%, in association with 23% increment in PON1 catalytic activity. In cells under oxidative stress [treated with AAPH-, or with oxidized LDL], PON1 activity was decreased by 31% or 40%, as compared to the activity observed in PON1 incubated with non-treated cells. We conclude that monocytes-macrophages possess free radicals scavenging activity, which is decreased under atherogenic conditions, and increased upon cell enrichment with potent antioxidants such as nutritional polyphenols, or PON1.

miRNAs mediate SnRK1-dependent energy signaling in Arabidopsis

The SnRK1 protein kinase, the plant ortholog of mammalian AMPK and yeast Snf1, is activated by the energy depletion caused by adverse environmental conditions. Upon activation, SnRK1 triggers extensive transcriptional changes to restore homeostasis and promote stress tolerance and survival partly through the inhibition of anabolism and the activation of catabolism. Despite the identification of a few bZIP transcription factors as downstream effectors, the mechanisms underlying gene regulation, and in particular gene repression by SnRK1, remain mostly unknown. microRNAs (miRNAs) are 20-24 nt RNAs that regulate gene expression post-transcriptionally by driving the cleavage and/or translation attenuation of complementary mRNA targets. In addition to their role in plant development, mounting evidence implicates miRNAs in the response to environmental stress. Given the involvement of miRNAs in stress responses and the fact that some of the SnRK1-regulated genes are miRNA targets, we postulated that miRNAs drive part of the transcriptional reprogramming triggered by SnRK1. By comparing the transcriptional response to energy deprivation between WT and dcl1-9, a mutant deficient in miRNA biogenesis, we identified 831 starvation genes misregulated in the dcl1-9 mutant, out of which 155 are validated or predicted miRNA targets. Functional clustering analysis revealed that the main cellular processes potentially co-regulated by SnRK1 and miRNAs are translation and organelle function and uncover TCP transcription factors as one of the most highly enriched functional clusters. TCP repression during energy deprivation was impaired in miR319 knockdown (MIM319) plants, demonstrating the involvement of miR319 in the stress-dependent regulation of TCPs. Altogether, our data indicates that miRNAs are components of the SnRK1 signaling cascade contributing to the regulation of specific mRNA targets and possibly tuning down particular cellular processes during the stress response.

Abstract P6-05-10: Progestins exert divergent growth effects and regulate tumor-unique gene cohorts in patient derived breast cancer xenografts

Background: Progesterone is an important hormone for development and normal function of the breast; however, its role in established breast cancers is less clear. Progestins have been implicated in regulating tumor cell growth, signaling, differentiation state, and stem/progenitor properties in breast cancer cells. High dose progestin treatment can be an effective therapy for some advanced breast tumors, through an unknown mechanism. Progesterone receptors (PRs) are considered positive prognostic indicators, although their levels vary considerably among luminal subtype breast tumors. Progestin/PR regulated genes in tumor cells have only been determined in cultured breast cancer cells and mouse mammary tumor models. Here we define tumor unique progestin-dependent growth effects and gene regulation profiles in patient-derived luminal breast tumor xenografts.

Methods: For these studies, three luminal estrogen receptor (ER)+PR+ transplantable xenografts were used that were derived from one pleural effusion and two previously untreated primary tumors. All three tumors were estrogen dependent to various degrees and contained variable levels of ER (5–90%) and PR (5–90%). Tumors were grown in vivo under continuous placebo, estrogen, or estrogen plus progestin conditions for 8–10 weeks and growth parameters monitored. Gene expression profiles were determined from dissected tumors using Affymetrix® GeneChip human gene 1.1 ST microarrays and results analyzed using Partek Genomics Suite software. Specific gene regulation was confirmed by q-RT-PCR and immunohistochemistry.

Results: Progestins had an inhibitory, neutral, and stimulatory effect on estrogen dependent growth in each of the three tumor lines. Accordingly, there was relatively little overlap in PR regulated genes between the three tumors. In the tumor in which progestin treatment had a potent anti-tumor effect, progestins were strong repressors of estrogen/ER-regulated genes. Gene expression patterns between the natural hormone progesterone and the synthetic drug MPA were compared in one tumor line and found to be mostly similar. The percent of PR+ tumor cells may have influenced the potency of gene regulation. Unique progestin regulated genes were discovered in this human tumor model system that were involved in immune response, cytokine signaling, and stem/progenitor cell features.

Conclusions: Women with breast cancer are exposed to progestins naturally or through hormonal therapies and these may have a profound effect on tumor biology. In some tumors, progestins are potently anti-proliferative, while in others they elicit the opposite effect and potentiate estrogen induced tumor growth. The diversity of progestin-regulated genes in each tumor underscores the hormone's context dependent effects. Determining progestin dependent gene signatures in patient tumors may pinpoint appropriate candidates for progestin therapy in advanced tumors and/or provide a prognostic tool for predicting tumor progression.

Funded by: NIH R01 CA140985 (C.A.S.), the Grohne Fund (P.K.), and the University of Colorado Cancer Center (C.A.S., P.K.)

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-05-10.