Abstract MP28: The Association Between the Saliva Microbiome and Biomarkers of Cardiometabolic Disease in ORIGINS

Introduction: The present study sought to characterize taxonomic and functional characteristics of the saliva microbiome and their cross-sectional association with cardiometabolic biomarkers.

Hypothesis: Features of the saliva microbiome will be associated with cardiometabolic risk.

Methods: Saliva microbiome composition from 265 ORIGINS participants was defined with 16S rRNA sequencing (Illumina, DADA2). Functional composition (KEGG orthologs; KOs) was inferred with PICRUSt2. Alpha Diversity was computed with the Shannon Index. Blood pressure was defined as normal (SBP<120, DBP<80, and no antihypertensive medication) vs elevated/high (hypertension: SBP≥120, DBP≥80 and/or antihypertensive medication). Prediabetes was defined as 5.7≤HbA1≤6.4% or 100≤fasting plasma glucose≤125 mg/dL. HOMA-IR was calculated from insulin and glucose. HOMA-IR and CRP were dichotomized as high/low using thresholds of 3 mg/L and 1.9, respectively. Multivariable multinomial regression with cross-validation was conducted for each feature (species, KOs) and outcome, ranking regression coefficients from most positively to most inversely associated features. Microbiota and KO ratios (Micro-R, KO-R) were computed as the log-ratio of the sum of abundances of taxa/KOs in the top vs bottom tertiles of cross-validated ranks, such that higher ratios are potentially adverse. Adjusted multivariable logistic regressions produced ORs summarizing the association between Shannon, Micro-R, and KO-R and each cardiometabolic outcome.

Results: Participants were 71% female, 22% Black, 40% Hispanic, and 18% white, with mean age of 33±10 years. Prevalence of hypertension was 36%, prediabetes was 17%, high CRP was 23%, and high HOMA-IR was 25%. Estimated ORs for the association between microbiome metrics and cardiometabolic outcomes are summarized in Figure 1.

Conclusion: Microbiome scores based on specific taxa or KOs are associated with hypertension, prediabetes, and increased inflammation and insulin resistance.

A Reproducible and Tunable Synthetic Soil Microbial Community Provides New Insights into Microbial Ecology

Microbial soil communities form commensal relationships with plants to promote the growth of both parties. The optimization of plant-microbe interactions to advance sustainable agriculture is an important field in agricultural research. However, investigation in this field is hindered by a lack of model microbial community systems and efficient approaches for building these communities. Two key challenges in developing standardized model communities are maintaining community diversity over time and storing/resuscitating these communities after cryopreservation, especially considering the different growth rates of organisms. Here, a model synthetic community (SynCom) of 16 soil microorganisms commonly found in the rhizosphere of diverse plant species, isolated from soil surrounding a single switchgrass plant, has been developed and optimized for in vitro experiments. The model soil community grows reproducibly between replicates and experiments, with a high community α-diversity being achieved through growth in low-nutrient media and through the adjustment of the starting composition ratios for the growth of individual organisms. The community can additionally be cryopreserved with glycerol, allowing for easy replication and dissemination of this in vitro system. Furthermore, the SynCom also grows reproducibly in fabricated ecosystem devices (EcoFABs), demonstrating the application of this community to an existing in vitro plant-microbe system. EcoFABs allow reproducible research in model plant systems, offering the precise control of environmental conditions and the easy measurement of plant microbe metrics. Our results demonstrate the generation of a stable and diverse microbial SynCom for the rhizosphere that can be used with EcoFAB devices and can be shared between research groups for maximum reproducibility. IMPORTANCE Microbes associate with plants in distinct soil communities to the benefit of both the soil microbes and the plants. Interactions between plants and these microbes can improve plant growth and health and are therefore a field of study in sustainable agricultural research. In this study, a model community of 16 soil bacteria has been developed to further the reproducible study of plant-soil microbe interactions. The preservation of the microbial community has been optimized for dissemination to other research settings. Overall, this work will advance soil microbe research through the optimization of a robust, reproducible model community.

Enhancing untargeted metabolomics using metadata-based source annotation

Human untargeted metabolomics studies annotate only ~10% of molecular features. We introduce reference-data-driven analysis to match metabolomics tandem mass spectrometry (MS/MS) data against metadata-annotated source data as a pseudo-MS/MS reference library. Applying this approach to food source data, we show that it increases MS/MS spectral usage 5.1-fold over conventional structural MS/MS library matches and allows empirical assessment of dietary patterns from untargeted data.

Nitrite Generating and Depleting Capacity of the Oral Microbiome and Cardiometabolic Risk: Results from ORIGINS

Background

The enterosalivary nitrate–nitrite–nitric oxide (NO 3 –NO 2 –NO) pathway generates NO following oral microbiota‐mediated production of salivary nitrite, potentially linking the oral microbiota to reduced cardiometabolic risk. Nitrite depletion by oral bacteria may also be important for determining the net nitrite available systemically. We examine if higher abundance of oral microbial genes favoring increased oral nitrite generation and decreased nitrite depletion is associated with a better cardiometabolic profile cross‐sectionally.

Methods and Results

This study includes 764 adults (mean [SD] age 32 [9] years, 71% women) enrolled in ORIGINS (Oral Infections, Glucose Intolerance, and Insulin Resistance Study). Microbial DNA from subgingival dental plaques underwent 16S rRNA gene sequencing; PICRUSt2 was used to estimate functional gene profiles. To represent the different components and pathways of nitrogen metabolism in bacteria, predicted gene abundances were operationalized to create summary scores by (1) bacterial nitrogen metabolic pathway or (2) biochemical product (NO 2 , NO, or ammonia [NH 3 ]) formed by the action of the bacterial reductases encoded. Finally, nitrite generation‐to‐depletion ratios of gene abundances were created from the above summary scores. A composite cardiometabolic Z score was created from cardiometabolic risk variables, with higher scores associated with worse cardiometabolic health. We performed multivariable linear regression analysis with cardiometabolic Z score as the outcome and the gene abundance summary scores and ratios as predictor variables, adjusting for sex, age, race, and ethnicity in the simple adjusted model. A 1 SD higher NO versus NH 3 summary ratio was inversely associated with a −0.10 (false discovery rate q =0.003) lower composite cardiometabolic Z score in simple adjusted models. Higher NH 3 summary score (suggestive of nitrite depletion) was associated with higher cardiometabolic risk, with a 0.06 (false discovery rate q =0.04) higher composite cardiometabolic Z score.

Conclusions

Increased net capacity for nitrite generation versus depletion by oral bacteria, assessed through a metagenome estimation approach, is associated with lower levels of cardiometabolic risk.

Early microbial markers of periodontal and cardiometabolic diseases in ORIGINS

Periodontitis affects up to 50% of individuals worldwide, and 8.5% are diagnosed with diabetes. The high-comorbidity rate of these diseases may suggest, at least in part, a shared etiology and pathophysiology. Changes in oral microbial communities have been documented in the context of severe periodontitis and diabetes, both independently and together. However, much less is known about the early oral microbial markers of these diseases. We used a subset of the ORIGINS project dataset, which collected detailed periodontal and cardiometabolic information from 787 healthy individuals, to identify early microbial markers of periodontitis and its association with markers of cardiometabolic health. Using state-of-the-art compositional data analysis tools, we identified the log-ratio of Treponema to Corynebacterium bacteria to be a novel Microbial Indicator of Periodontitis (MIP), and found that this MIP correlates with poor periodontal health and cardiometabolic markers early in disease pathogenesis in both subgingival plaque and saliva.

Emergence of an early SARS-CoV-2 epidemic in the United States

The emergence of the COVID-19 epidemic in the United States (U.S.) went largely undetected due to inadequate testing. New Orleans experienced one of the earliest and fastest accelerating outbreaks, coinciding with Mardi Gras. To gain insight into the emergence of SARS-CoV-2 in the U.S. and how large-scale events accelerate transmission, we sequenced SARS-CoV-2 genomes during the first wave of the COVID-19 epidemic in Louisiana. We show that SARS-CoV-2 in Louisiana had limited diversity compared to other U.S. states and that one introduction of SARS-CoV-2 led to almost all of the early transmission in Louisiana. By analyzing mobility and genomic data, we show that SARS-CoV-2 was already present in New Orleans before Mardi Gras, and the festival dramatically accelerated transmission. Our study provides an understanding of how superspreading during large-scale events played a key role during the early outbreak in the U.S. and can greatly accelerate epidemics.

SARS-CoV-2 detection status associates with bacterial community composition in patients and the hospital environment

BACKGROUND

SARS-CoV-2 is an RNA virus responsible for the coronavirus disease 2019 (COVID-19) pandemic. Viruses exist in complex microbial environments, and recent studies have revealed both synergistic and antagonistic effects of specific bacterial taxa on viral prevalence and infectivity. We set out to test whether specific bacterial communities predict SARS-CoV-2 occurrence in a hospital setting.

METHODS

We collected 972 samples from hospitalized patients with COVID-19, their health care providers, and hospital surfaces before, during, and after admission. We screened for SARS-CoV-2 using RT-qPCR, characterized microbial communities using 16S rRNA gene amplicon sequencing, and used these bacterial profiles to classify SARS-CoV-2 RNA detection with a random forest model.

RESULTS

Sixteen percent of surfaces from COVID-19 patient rooms had detectable SARS-CoV-2 RNA, although infectivity was not assessed. The highest prevalence was in floor samples next to patient beds (39%) and directly outside their rooms (29%). Although bed rail samples more closely resembled the patient microbiome compared to floor samples, SARS-CoV-2 RNA was detected less often in bed rail samples (11%). SARS-CoV-2 positive samples had higher bacterial phylogenetic diversity in both human and surface samples and higher biomass in floor samples. 16S microbial community profiles enabled high classifier accuracy for SARS-CoV-2 status in not only nares, but also forehead, stool, and floor samples. Across these distinct microbial profiles, a single amplicon sequence variant from the genus Rothia strongly predicted SARS-CoV-2 presence across sample types, with greater prevalence in positive surface and human samples, even when compared to samples from patients in other intensive care units prior to the COVID-19 pandemic.

CONCLUSIONS

These results contextualize the vast diversity of microbial niches where SARS-CoV-2 RNA is detected and identify specific bacterial taxa that associate with the viral RNA prevalence both in the host and hospital environment. Video Abstract.

A comparison of DNA/RNA extraction protocols for high-throughput sequencing of microbial communities

One goal of microbial ecology researchers is to capture the maximum amount of information from all organisms in a sample. The recent COVID-19 pandemic, caused by the RNA virus SARS-CoV-2, has highlighted a gap in traditional DNA-based protocols, including the high-throughput methods the authors previously established as field standards. To enable simultaneous SARS-CoV-2 and microbial community profiling, the authors compared the relative performance of two total nucleic acid extraction protocols with the authors' previously benchmarked protocol. The authors included a diverse panel of environmental and host-associated sample types, including body sites commonly swabbed for COVID-19 testing. Here the authors present results comparing the cost, processing time, DNA and RNA yield, microbial community composition, limit of detection and well-to-well contamination between these protocols.

Emergence of an early SARS-CoV-2 epidemic in the United States

The emergence of the early COVID-19 epidemic in the United States (U.S.) went largely undetected, due to a lack of adequate testing and mitigation efforts. The city of New Orleans, Louisiana experienced one of the earliest and fastest accelerating outbreaks, coinciding with the annual Mardi Gras festival, which went ahead without precautions. To gain insight into the emergence of SARS-CoV-2 in the U.S. and how large, crowded events may have accelerated early transmission, we sequenced SARS-CoV-2 genomes during the first wave of the COVID-19 epidemic in Louisiana. We show that SARS-CoV-2 in Louisiana initially had limited sequence diversity compared to other U.S. states, and that one successful introduction of SARS-CoV-2 led to almost all of the early SARS-CoV-2 transmission in Louisiana. By analyzing mobility and genomic data, we show that SARS-CoV-2 was already present in New Orleans before Mardi Gras and that the festival dramatically accelerated transmission, eventually leading to secondary localized COVID-19 epidemics throughout the Southern U.S.. Our study provides an understanding of how superspreading during large-scale events played a key role during the early outbreak in the U.S. and can greatly accelerate COVID-19 epidemics on a local and regional scale.

Feasibility of using alternative swabs and storage solutions for paired SARS-CoV-2 detection and microbiome analysis in the hospital environment

BACKGROUND

Determining the role of fomites in the transmission of SARS-CoV-2 is essential in the hospital setting and will likely be important outside of medical facilities as governments around the world make plans to ease COVID-19 public health restrictions and attempt to safely reopen economies. Expanding COVID-19 testing to include environmental surfaces would ideally be performed with inexpensive swabs that could be transported safely without concern of being a source of new infections. However, CDC-approved clinical-grade sampling supplies and techniques using a synthetic swab are expensive, potentially expose laboratory workers to viable virus and prohibit analysis of the microbiome due to the presence of antibiotics in viral transport media (VTM). To this end, we performed a series of experiments comparing the diagnostic yield using five consumer-grade swabs (including plastic and wood shafts and various head materials including cotton, synthetic, and foam) and one clinical-grade swab for inhibition to RNA. For three of these swabs, we evaluated performance to detect SARS-CoV-2 in twenty intensive care unit (ICU) hospital rooms of patients including COVID-19+ patients. All swabs were placed in 95% ethanol and further evaluated in terms of RNase activity. SARS-CoV-2 was measured both directly from the swab and from the swab eluent.

RESULTS

Compared to samples collected in VTM, 95% ethanol demonstrated significant inhibition properties against RNases. When extracting directly from the swab head as opposed to the eluent, RNA recovery was approximately 2-4× higher from all six swab types tested as compared to the clinical standard of testing the eluent from a CDC-approved synthetic (SYN) swab. The limit of detection (LoD) of SARS-CoV-2 from floor samples collected using the consumer-grade plastic (CGp) or research-grade plastic The Microsetta Initiative (TMI) swabs was similar or better than the SYN swab, further suggesting that swab type does not impact RNA recovery as measured by the abundance of SARS-CoV-2. The LoD for TMI was between 0 and 362.5 viral particles, while SYN and CGp were both between 725 and 1450 particles. Lastly microbiome analyses (16S rRNA gene sequencing) of paired samples (nasal and floor from same patient room) collected using different swab types in triplicate indicated that microbial communities were not impacted by swab type, but instead driven by the patient and sample type.

CONCLUSIONS

Compared to using a clinical-grade synthetic swab, detection of SARS-CoV-2 from environmental samples collected from ICU rooms of patients with COVID was similar using consumer-grade swabs, stored in 95% ethanol. The yield was best from the swab head rather than the eluent and the low level of RNase activity and lack of antibiotics in these samples makes it possible to perform concomitant microbiome analyses. Video abstract.

Feasibility of using alternative swabs and storage solutions for paired SARS-CoV-2 detection and microbiome analysis in the hospital environment

Background Determining the role of fomites in the transmission of SARS-CoV-2 is essential in the hospital setting and will likely be important outside of medical facilities as governments around the world make plans to ease COVID-19 public health restrictions and attempt to safely reopen economies. Expanding COVID-19 testing to include environmental surfaces would ideally be performed with inexpensive swabs that could be transported safely without concern of being a source of new infections. However, CDC-approved clinical-grade sampling supplies and techniques using a synthetic swab are expensive, potentially expose laboratory workers to viable virus and prohibit analysis of the microbiome due to the presence of antibiotics in viral transport media (VTM). To this end, we performed a series of experiments comparing the diagnostic yield using five consumer-grade swabs (including plastic and wood shafts and various head materials including cotton, synthetic, and foam) and one clinical grade swab for inhibition to RNA. For three of these swabs, we evaluated performance to detect SARS-CoV-2 in twenty intensive care unit (ICU) hospital rooms of patients including COVID-19+ patients. All swabs were placed in 95% ethanol and further evaluated in terms of RNase activity. SARS-CoV-2 was measured both directly from the swab and from the swab eluent. Results Compared to samples collected in VTM, 95% ethanol demonstrated significant inhibition properties against RNases. When extracting directly from the swab head as opposed to the eluent, RNA recovery was approximately 2-4x higher from all six swab types tested as compared to the clinical standard of testing the eluent from a CDC-approved synthetic (SYN) swab. The limit of detection (LoD) of SARSSARS-CoV-2 from floor samples collected using the consumer-grade plastic (CGp) or research-grade plastic The Microsetta Initiative (TMI) swabs was similar or better than the SYN swab, further suggesting that swab type does not impact RNA recovery as measured by the abundance of SARSSARS-CoV-2. The LoD for TMI was between 0-362.5 viral particles while SYN and CGp were both between 725-1450 particles. Lastly microbiome analyses (16S rRNA gene sequencing) of paired samples (nasal and floor from same patient-room) collected using different swab types in triplicate indicated that microbial communities were not impacted by swab type, but instead driven by the patient and sample type. Conclusions Compared to using a clinical-grade synthetic swab, detection of SARS-CoV-2 from environmental samples collected from ICU rooms of patients with COVID was similar using consumer grade swabs, stored in 95% ethanol. The yield was best from the swab head rather than the eluent and the low level of RNase activity and lack of antibiotics in these samples makes it possible to perform concomitant microbiome analyses.

Feasibility of using alternative swabs and storage solutions for paired SARS-CoV-2 detection and microbiome analysis in the hospital environment

Background

Determining the role of fomites in the transmission of SARS-CoV-2 is essential in the hospital setting and will likely be important outside of medical facilities as governments around the world make plans to ease COVID-19 public health restrictions and attempt to safely reopen economies. Expanding COVID-19 testing to include environmental surfaces would ideally be performed with inexpensive swabs that could be transported safely without concern of being a source of new infections. However, CDC-approved clinical-grade sampling supplies and techniques using a synthetic swab are expensive, potentially expose laboratory workers to viable virus and prohibit analysis of the microbiome due to the presence of antibiotics in viral transport media (VTM). To this end, we performed a series of experiments comparing the diagnostic yield using five consumer-grade swabs (including plastic and wood shafts and various head materials including cotton, synthetic, and foam) and one clinical grade swab for inhibition to RNA. For three of these swabs, we evaluated performance to detect SARS-CoV-2 in twenty intensive care unit (ICU) hospital rooms of patients including COVID-19+ patients. All swabs were placed in 95% ethanol and further evaluated in terms of RNase activity. SARS-CoV-2 was measured both directly from the swab and from the swab eluent.

Results

Compared to samples collected in VTM, 95% ethanol demonstrated significant inhibition properties against RNases. When extracting directly from the swab head as opposed to the eluent, RNA recovery was approximately 2-4x higher from all six swab types tested as compared to the clinical standard of testing the eluent from a CDC-approved synthetic (SYN) swab. The limit of detection (LoD) of SARSSARS-CoV-2 from floor samples collected using the consumer-grade plastic (CGp) or research-grade plastic The Microsetta Initiative (TMI) swabs was similar or better than the SYN swab, further suggesting that swab type does not impact RNA recovery as measured by the abundance of SARSSARS-CoV-2. The LoD for TMI was between 0-362.5 viral particles while SYN and CGp were both between 725-1450 particles. Lastly microbiome analyses (16S rRNA gene sequencing) of paired samples (nasal and floor from same patient-room) collected using different swab types in triplicate indicated that microbial communities were not impacted by swab type, but instead driven by the patient and sample type.

Conclusions

Compared to using a clinical-grade synthetic swab, detection of SARS-CoV-2 from environmental samples collected from ICU rooms of patients with COVID was similar using consumer grade swabs, stored in 95% ethanol. The yield was best from the swab head rather than the eluent and the low level of RNase activity and lack of antibiotics in these samples makes it possible to perform concomitant microbiome analyses.

Microbial context predicts SARS-CoV-2 prevalence in patients and the hospital built environment

Synergistic effects of bacteria on viral stability and transmission are widely documented but remain unclear in the context of SARS-CoV-2. We collected 972 samples from hospitalized ICU patients with coronavirus disease 2019 (COVID-19), their health care providers, and hospital surfaces before, during, and after admission. We screened for SARS-CoV-2 using RT-qPCR, characterized microbial communities using 16S rRNA gene amplicon sequencing, and contextualized the massive microbial diversity in this dataset in a meta-analysis of over 20,000 samples. Sixteen percent of surfaces from COVID-19 patient rooms were positive, with the highest prevalence in floor samples next to patient beds (39%) and directly outside their rooms (29%). Although bed rail samples increasingly resembled the patient microbiome throughout their stay, SARS-CoV-2 was less frequently detected there (11%). Despite surface contamination in almost all patient rooms, no health care workers providing COVID-19 patient care contracted the disease. SARS-CoV-2 positive samples had higher bacterial phylogenetic diversity across human and surface samples, and higher biomass in floor samples. 16S microbial community profiles allowed for high classifier accuracy for SARS-CoV-2 status in not only nares, but also forehead, stool and floor samples. Across these distinct microbial profiles, a single amplicon sequence variant from the genus Rothia was highly predictive of SARS-CoV-2 across sample types, and had higher prevalence in positive surface and human samples, even when comparing to samples from patients in another intensive care unit prior to the COVID-19 pandemic. These results suggest that bacterial communities contribute to viral prevalence both in the host and hospital environment.

SARS-CoV-2 Screening Among Symptom-Free Healthcare Workers

Background

Transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is possible among symptom-free individuals and some patients are avoiding medically necessary healthcare visits for fear of becoming infected in the healthcare setting. Limited data are available on the point prevalence of SARS-CoV-2 infection in symptom-free U.S. healthcare workers (HCW).

Methods

A cross-sectional convenience sample of symptom-free HCWs from the metropolitan area surrounding Minneapolis and St. Paul, Minnesota was enrolled between April 20 ^th and June 24 ^th , 2020. A participant self-collected nasopharyngeal swab (NPS) was obtained. SARS-CoV-2 infection was assessed via polymerase chain reaction. Participants were queried about their willingness to repeat a self-collection NPS for diagnostic purposes. We had >95% power to detect at least one positive test if the true underlying prevalence of SARS-CoV2 was ≥1%.

Results

Among n=489 participants 80% were female and mean age±SD was 41±11. Participants reported being physicians (14%), nurse practitioners (8%), physician's assistants (4%), nurses (51%), medics (3%), or other which predominantly included laboratory technicians and administrative roles (22%). Exposure to a known/suspected COVID-19 case in the 14 days prior to enrollment was reported in 40% of participants. SARS-CoV-2 was not detected in any participant. Over 95% of participants reported a willingness to repeat a self-collected NP swab in the future.

Conclusions

The point prevalence of SARS-CoV-2 infection was likely <1% in a convenience sample of symptom-free Minnesota healthcare workers from April 20 ^th and June 24 ^th , 2020. Self-collected NP swabs are well-tolerated and a viable alternative to provider-collected swabs to preserve PPE.

A comparison of DNA/RNA extraction protocols for high-throughput sequencing of microbial communities

One goal among microbial ecology researchers is to capture the maximum amount of information from all organisms in a sample. The recent COVID-19 pandemic, caused by the RNA virus SARS-CoV-2, has highlighted a gap in traditional DNA-based protocols, including the high-throughput methods we previously established as field standards. To enable simultaneous SARS-CoV-2 and microbial community profiling, we compare the relative performance of two total nucleic acid extraction protocols and our previously benchmarked protocol. We included a diverse panel of environmental and host-associated sample types, including body sites commonly swabbed for COVID-19 testing. Here we present results comparing the cost, processing time, DNA and RNA yield, microbial community composition, limit of detection, and well-to-well contamination, between these protocols.

Accession numbers

Raw sequence data were deposited at the European Nucleotide Archive (accession#: ERP124610) and raw and processed data are available at Qiita (Study ID: 12201). All processing and analysis code is available on GitHub ( github.com/justinshaffer/Extraction_test_MagMAX ).

Methods summary

To allow for downstream applications involving RNA-based organisms such as SARS-CoV-2, we compared the two extraction protocols designed to extract DNA and RNA against our previously established protocol for extracting only DNA for microbial community analyses. Across 10 diverse sample types, one of the two protocols was equivalent or better than our established DNA-based protocol. Our conclusion is based on per-sample comparisons of DNA and RNA yield, the number of quality sequences generated, microbial community alpha- and beta-diversity and taxonomic composition, the limit of detection, and extent of well-to-well contamination.

Handwashing and Detergent Treatment Greatly Reduce SARS-CoV-2 Viral Load on Halloween Candy Handled by COVID-19 Patients

Due to the COVID-19 pandemic and potential public health implications, we are publishing this peer-reviewed manuscript in its accepted form. The final, copyedited version of the paper will be available at a later date. Although SARS-CoV-2 is primarily transmitted by respiratory droplets and aerosols, transmission by fomites remains plausible. During Halloween, a major event for children in numerous countries, SARS-CoV-2 transmission risk via candy fomites worries many parents. To address this concern, we enrolled 10 recently diagnosed asymptomatic or mildly/moderately symptomatic COVID-19 patients to handle typical Halloween candy (pieces individually wrapped) under three conditions: normal handling with unwashed hands, deliberate coughing and extensive touching, and normal handling following handwashing. We then used a factorial design to subject the candies to two post-handling treatments: no washing (untreated) and household dishwashing detergent. We measured SARS-CoV-2 load by RT-qPCR and LAMP. From the candies not washed post-handling, we detected SARS-CoV-2 on 60% of candies that were deliberately coughed on, 60% of candies normally handled with unwashed hands, but only 10% of candies handled after hand washing. We found that treating candy with dishwashing detergent reduced SARS-CoV-2 load by 62.1% in comparison to untreated candy. Taken together, these results suggest that although the risk of transmission of SARS-CoV-2 by fomites is low even from known COVID-19 patients, viral RNA load can be reduced to near zero by the combination of handwashing by the infected patient and ≥1 minute detergent treatment after collection. We also found that the inexpensive and fast LAMP protocol was more than 80% concordant with RT-qPCR.IMPORTANCE The COVID-19 pandemic is leading to important tradeoffs between risk of SARS-CoV-2 transmission and mental health due to deprivation from normal activities, with these impacts being especially profound in children. Due to the ongoing pandemic, Halloween activities will be curtailed as a result of the concern that candy from strangers might act as fomites. Here we demonstrate that these risks can be mitigated by ensuring that prior to handling candy, the candy giver washes their hands, and by washing collected candy with household dishwashing detergent. Even in the most extreme case, with candy deliberately coughed on by known COVID-19 patients, viral load was reduced dramatically after washing with household detergent. We conclude that with reasonable precautions, even if followed only by either the candy giver or the candy recipient, the risk of viral transmission by this route is very low.

Feasibility of using alternative swabs and storage solutions for paired SARS-CoV-2 detection and microbiome analysis in the hospital environment

Background Determining the role of fomites in the transmission of SARS-CoV-2 is essential in the hospital setting and will likely be important outside of medical facilities as governments around the world make plans to ease COVID-19 public health restrictions and attempt to safely reopen economies. Expanding COVID-19 testing to include environmental surfaces would ideally be performed with inexpensive swabs that could be transported safely without concern of being a source of new infections. However, CDC-approved clinical-grade sampling supplies and techniques using a synthetic swab are expensive, potentially expose laboratory workers to viable virus and prohibit analysis of the microbiome due to the presence of antibiotics in viral transport media (VTM). To this end, we performed a series of experiments comparing the diagnostic yield using five consumer-grade swabs (including plastic and wood shafts and various head materials including cotton, synthetic, and foam) and one clinical grade swab for inhibition to RNA. For three of these swabs, we evaluated performance to detect SARS-CoV-2 in twenty intensive care unit (ICU) hospital rooms of patients with 16 COVID-19+. All swabs were placed in 95% ethanol and further evaluated in terms of RNase activity. SARS-CoV-2 was measured both directly from the swab and from the swab eluent. Results Compared to samples collected in VTM, 95% ethanol demonstrated significant inhibition properties against RNases. When extracting directly from the swab head as opposed to the eluent, RNA recovery was approximately 2-4x higher from all six swab types tested as compared to the clinical standard of testing the eluent from a CDC-approved synthetic swab. The limit of detection (LoD) of SARs-CoV-2 from floor samples collected using the CGp or TMI swabs was similar or better than the CDC standard, further suggesting that swab type does not impact RNA recovery as measured by SARs-CoV-2. The LoD for TMI was between 0-362.5 viral particles while SYN and CGp were both between 725-1450 particles. Lastly microbiome analyses (16S rRNA) of paired samples (e.g., environment to host) collected using different swab types in triplicate indicated that microbial communities were not impacted by swab type but instead driven by the patient and sample type (floor or nasal). Conclusions Compared to using a clinical-grade synthetic swab, detection of SARS-CoV-2 from environmental samples collected from ICU rooms of patients with COVID was similar using consumer grade swabs, stored in 95% ethanol. The yield was best from the swab head rather than the eluent and the low level of RNase activity in these samples makes it possible to perform concomitant microbiome analysis. Keywords: COVID-19, SARS-CoV-2, RT-qPCR, swab, global health.

Linking metabolic phenotypes to pathogenic traits among "Candidatus Liberibacter asiaticus" and its hosts

Candidatus Liberibacter asiaticus (CLas) has been associated with Huanglongbing, a lethal vector-borne disease affecting citrus crops worldwide. While comparative genomics has provided preliminary insights into the metabolic capabilities of this uncultured microorganism, a comprehensive functional characterization is currently lacking. Here, we reconstructed and manually curated genome-scale metabolic models for the six CLas strains A4, FL17, gxpsy, Ishi-1, psy62, and YCPsy, in addition to a model of the closest related culturable microorganism, L. crescens BT-1. Predictions about nutrient requirements and changes in growth phenotypes of CLas were confirmed using in vitro hairy root-based assays, while the L. crescens BT-1 model was validated using cultivation assays. Host-dependent metabolic phenotypes were revealed using expression data obtained from CLas-infected citrus trees and from the CLas-harboring psyllid Diaphorina citri Kuwayama. These results identified conserved and unique metabolic traits, as well as strain-specific interactions between CLas and its hosts, laying the foundation for the development of model-driven Huanglongbing management strategies.

Author Correction: Reproducible, interactive, scalable and extensible microbiome data science using QIIME 2

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Triplicate PCR reactions for 16S rRNA gene amplicon sequencing are unnecessary

Conventional wisdom holds that PCR amplification for sequencing should employ pooled replicate reactions to reduce bias due to jackpot effects and chimera formation. However, modern amplicon data analysis employs methods that may be less sensitive to such artifacts. Here we directly compare results from single versus triplicate reactions for 16S amplicon sequencing and find no significant impact of adopting a less labor-intensive single-reaction protocol.

Establishing microbial composition measurement standards with reference frames

Differential abundance analysis is controversial throughout microbiome research. Gold standard approaches require laborious measurements of total microbial load, or absolute number of microorganisms, to accurately determine taxonomic shifts. Therefore, most studies rely on relative abundance data. Here, we demonstrate common pitfalls in comparing relative abundance across samples and identify two solutions that reveal microbial changes without the need to estimate total microbial load. We define the notion of "reference frames", which provide deep intuition about the compositional nature of microbiome data. In an oral time series experiment, reference frames alleviate false positives and produce consistent results on both raw and cell-count normalized data. Furthermore, reference frames identify consistent, differentially abundant microbes previously undetected in two independent published datasets from subjects with atopic dermatitis. These methods allow reassessment of published relative abundance data to reveal reproducible microbial changes from standard sequencing output without the need for new assays.

Impacts of the Human Gut Microbiome on Therapeutics

The human microbiome contains a vast source of genetic and biochemical variation, and its impacts on therapeutic responses are just beginning to be understood. This expanded understanding is especially important because the human microbiome differs far more among different people than does the human genome, and it is also dramatically easier to change. Here, we describe some of the major factors driving differences in the human microbiome among individuals and populations. We then describe some of the many ways in which gut microbes modify the action of specific chemotherapeutic agents, including nonsteroidal anti-inflammatory drugs and cardiac glycosides, and outline the potential of fecal microbiota transplant as a therapeutic. Intriguingly, microbes also alter how hosts respond to therapeutic agents through various pathways acting at distal sites. Finally, we discuss some of the computational and practical issues surrounding use of the microbiome to stratify individuals for drug response, and we envision a future where the microbiome will be modified to increase everyone's potential to benefit from therapy.

The Microbiome and Human Biology

Over the past few years, microbiome research has dramatically reshaped our understanding of human biology. New insights range from an enhanced understanding of how microbes mediate digestion and disease processes (e.g., in inflammatory bowel disease) to surprising associations with Parkinson's disease, autism, and depression. In this review, we describe how new generations of sequencing technology, analytical advances coupled to new software capabilities, and the integration of animal model data have led to these new discoveries. We also discuss the prospects for integrating studies of the microbiome, metabolome, and immune system, with the goal of elucidating mechanisms that govern their interactions. This systems-level understanding will change how we think about ourselves as organisms.

Divergent clonal evolution of castration-resistant neuroendocrine prostate cancer

An increasingly recognized resistance mechanism to androgen receptor (AR)-directed therapy in prostate cancer involves epithelial plasticity, in which tumor cells demonstrate low to absent AR expression and often have neuroendocrine features. The etiology and molecular basis for this 'alternative' treatment-resistant cell state remain incompletely understood. Here, by analyzing whole-exome sequencing data of metastatic biopsies from patients, we observed substantial genomic overlap between castration-resistant tumors that were histologically characterized as prostate adenocarcinomas (CRPC-Adeno) and neuroendocrine prostate cancer (CRPC-NE); analysis of biopsy samples from the same individuals over time points to a model most consistent with divergent clonal evolution. Genome-wide DNA methylation analysis revealed marked epigenetic differences between CRPC-NE tumors and CRPC-Adeno, and also designated samples of CRPC-Adeno with clinical features of AR independence as CRPC-NE, suggesting that epigenetic modifiers may play a role in the induction and/or maintenance of this treatment-resistant state. This study supports the emergence of an alternative, 'AR-indifferent' cell state through divergent clonal evolution as a mechanism of treatment resistance in advanced prostate cancer.

Abstract B41: Targeting androgen-independent prostate cancer through epigenetic reprogramming

Background and aim of the study: The mainstay of therapy for patients with metastatic prostate cancer, including castration resistant disease (CRPC), is hormonal therapy targeting the androgen receptor (AR). However, tumors ultimately develop treatment resistance, which can include epithelial plasticity associated with loss of AR expression, clinical aggressiveness, and pathologic features of small cell or neuroendocrine carcinoma (NEPC). We recently preformed integrative molecular analyses of metastatic tumors from a large cohort of CRPC and NEPC patients. Emerging data from this study points to a key role of the Polycomb gene EZH2 and the epigenome in driving this adaptive response mechanism. In this study we are now exploring the hypothesis that the epigenetic modifier, EZH2, can lead the adaptive response towards an androgen-independent phenotype and towards the appearance of neuroendocrine features.

Results: Based on the driving role of EZH2 in other tumor types and significant overexpression in NEPC tumors (confirmed at a protein level on Tissue Microarray), we evaluated the effects of the EZH2 inhibitor, GSK343, in NEPC cells (NCI-H660) and prostate adenocarcinoma cells (LNCaP and DU145) in 3D Matrigel cultures. GSK343 effectively inhibited H3K27me3 and resulted in a significant reduction of NCI-H660 viability, measured with an ATP-based assay, whereas LNCaP and DU145 cells were minimally affected after 7 or 14 days of treatment. Using a nanosting assay we also demonstrated a significant increase in the expression of AR signaling genes (such as PSA, PSMA) and decrease in NEPC-associated genes (chromogranin A, AURKA, ENO2) when neuroendocrine cells are treated with EZH2 inhibitor. These data suggest a modulation of the neuroendocrine phenotype via EZH2. We therefore extended these drug studies including patient-derived organoid models including both CRPC and NEPC organoids, and we observed similar results with preferential sensitivity of the AR-negative NEPC organoids to the AR-positive CRPC organoid, with similar reversion of downstream AR/NEPC gene expression.

Conclusions: There is no approved drug that can specifically target AR- independent NEPC tumors. The restricted set of therapeutic options against this subtype of prostate cancer and consequent dismal outcome stem in part from our incomplete understanding of the molecular events underlying its pathogenesis. The discovery that epigenetics can be a key process in distinguishing tumors that are AR-independent and at high risk for NEPC progression represents an important step to highlight the use of epigenetic modifiers as therapeutic agents for this subtype of prostate cancer.

Citation Format: Loredana Puca, Dong Gao, Myriam Kossai, Joanna Cyrta, Clarisse Marotz, Juan Miguel Mosquera, Theresa Y. MacDonald, Andrea Sboner, Rema Rao, Yu Chen, Mark A. Rubin, Himisha Beltran. Targeting androgen-independent prostate cancer through epigenetic reprogramming. [abstract]. In: Proceedings of the AACR Special Conference on Chromatin and Epigenetics in Cancer; Sep 24-27, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2016;76(2 Suppl):Abstract nr B41.

SPOP mutation leads to genomic instability in prostate cancer

Genomic instability is a fundamental feature of human cancer often resulting from impaired genome maintenance. In prostate cancer, structural genomic rearrangements are a common mechanism driving tumorigenesis. However, somatic alterations predisposing to chromosomal rearrangements in prostate cancer remain largely undefined. Here, we show that SPOP, the most commonly mutated gene in primary prostate cancer modulates DNA double strand break (DSB) repair, and that SPOP mutation is associated with genomic instability. In vivo, SPOP mutation results in a transcriptional response consistent with BRCA1 inactivation resulting in impaired homology-directed repair (HDR) of DSB. Furthermore, we found that SPOP mutation sensitizes to DNA damaging therapeutic agents such as PARP inhibitors. These results implicate SPOP as a novel participant in DSB repair, suggest that SPOP mutation drives prostate tumorigenesis in part through genomic instability, and indicate that mutant SPOP may increase response to DNA-damaging therapeutics.

Abstract LB-018: Defining a molecular subclass of treatment-resistant prostate cancer

Background: A subset of advanced prostate cancers can progress from an androgen driven state to androgen receptor (AR) independence, often associated with low or absent AR expression and extensive neuroendocrine differentiation. Once neuroendocrine prostate cancer (NEPC) develops, patients typically demonstrate an aggressive clinical course, resistance to AR therapies, and poor overall survival. Early diagnosis is important but remains challenging as the clinical and pathologic features associate with AR independence and NEPC are currently poorly defined.

Methods: To address this gap in knowledge, we performed whole exome sequencing (WES) of 124 metastatic tumors from 81 patients including 35 with morphologic features of NEPC. Patients with serial or synchronous samples were included to characterize disease heterogeneity and the transition from adenocarcinoma to NEPC. Immunohistochemistry was performed for neuroendocrine markers and AR in all cases. Computational analysis of clonality and allele specific quantification of copy number were performed using CLONET. Expression profiling (RNA-seq and/or quantitative assessment of a targeted panel of AR signaling genes by Nanostring) and DNA methylation were evaluated in the context of genomic changes.

Results: The mutational landscape of NEPC and castration resistant prostate cancer (CRPC) did not differ significantly by rate of non-synonymous mutations or copy number burden (on average &gt;40% of the genome was aberrant), and polyploidy was frequently detected together with common allelic imbalances. Comparative analysis at the DNA and mRNA level identified significant decrease in AR signaling in NEPC and a range of AR signaling in CRPC, enrichment of copy number losses (including RB1 and multiple genes on 16q) in NEPC, and focal high level AR amplification in CRPC in contrast to NEPCs (p-val = 0.0007). DNA allele specific analysis of multi-sample cases including patient matched adenocarcinoma-NEPC tumors suggested diverse genomic state of key lesions including aberrations in MYCN and CDKN1B.

Conclusions: This is largest study to date focused on the molecular landscape of the NEPC resistance phenotype. NEPC is characterized by a molecular profile defined by distinct genomic alterations and decreased AR signaling. A subgroup of CRPC demonstrates lower AR signaling and molecular overlap with NEPC. This study supports clonal evolution of prostate adenocarcinoma to NEPC, provides new insight into NEPC biology and disease heterogeneity, and may aid in the detection of AR independence and emergence of the NEPC subclass of treatment resistance.

Citation Format: Himisha Beltran, Davide Prandi, Juan Miguel Mosquera, Eugenia Giannopoulou, Loredana Puca, Clarisse Marotz, David M. Nanus, Scott T. Tagawa, Olivier Elemento, Eliezer Van Allen, Andrea Sboner, Levi Garraway, Mark A. Rubin, Francesca Demichelis. Defining a molecular subclass of treatment-resistant prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-018. doi:10.1158/1538-7445.AM2015-LB-018

Abstract 1108: SPOP mutation leads to genomic instability in prostate cancer

Background:

Genomic instability is a fundamental feature of human cancer, and DNA repair defects resulting in impaired genome maintenance promote pathogenesis of many types of cancers. In prostate cancer, structural genomic rearrangements, including translocations and copy number aberrations, are a key mechanism driving tumorigenesis. Recently, whole genome sequencing revealed a striking abundance, complexity, and heterogeneity of genomic rearrangements, potentially suggesting distinct mechanisms of instability in different molecular classes of prostate cancer. However, the somatic alterations underlying these phenomena remain largely undefined.

Recurrent mutations in SPOP, the substrate-recognition component of an E3-ubiquitin ligase, represent the most common point mutations in primary prostate cancer, occurring in about 10% of tumors. SPOP mutations define a distinct molecular class of prostate cancer; they are mutually exclusive with TMPRSS2-ERG fusions, but harbor distinct patterns of copy number aberrations. Here, we report that SPOP mutant prostate cancers also harbor increased numbers of genomic rearrangements, and functional data suggest that SPOP mutation alters repair of DNA double strand breaks (DSB).

Methods:

We systematically investigated somatic alterations associated with genomic rearrangements, using a composite data set of 402 clinically localized prostate cancers. Functional analyses in vitro and in vivo were used to define pathways affected, and interrogate DNA repair phenotypes.

Results:

In human prostate cancers, SPOP mutation is an early event specifically associated with increased intrachromosomal genomic rearrangements. Using a zebrafish model, SPOP mutation results in a transcriptional response consistent with BRCA1 inactivation, implicating altered repair of DSB. In vitro data suggest that SPOP participates in repair of DSB, and SPOP mutation impairs homology-directed repair (HDR), instead promoting error-prone non-homologous end joining (NHEJ). Finally, SPOP mutation sensitizes prostate cancer cells to DNA damaging therapeutic agents such as PARP inhibitors.

Conclusions:

These results implicate SPOP as a novel participant in DSB repair, suggest that SPOP mutation drives prostate tumorigenesis in part through genomic instability, and indicate that SPOP mutant prostate cancer may be selectively responsive to DNA damaging therapeutics.

Citation Format: Gunther Boysen, Christopher E. Barbieri, Davide Prandi, Sung-Suk Chae, Srilakshmi Nataraj, Mirjam Blattner, Clarisse Marotz, Limei Xu, Paola Lecca, Sagar Chhangawala, Pengbo Zou, Andrea Sboner, Francesca Demichelis, Yariv Houvras, Mark A. Rubin. SPOP mutation leads to genomic instability in prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1108. doi:10.1158/1538-7445.AM2015-1108

Abstract NG01: SPOP mutation is associated with genomic instability in prostate cancer

Background: Genomic instability is a fundamental feature of human cancer, and DNA repair defects resulting in impaired genome maintenance promote pathogenesis of many types of cancers. In prostate cancer, structural genomic rearrangements, including translocations and copy number aberrations, are a key mechanism driving tumorigenesis. Recently, whole genome sequencing revealed a striking abundance, complexity, and heterogeneity of genomic rearrangements, potentially suggesting distinct mechanisms of instability in different molecular classes of prostate cancer. However, the somatic alterations underlying these phenomena remain largely undefined.

Recurrent mutations in SPOP, the substrate-recognition component of an E3-ubiquitin ligase, represent the most common point mutations in primary prostate cancer, occurring in about 10% of tumors. SPOP mutations define a distinct molecular class of prostate cancer; they are mutually exclusive with TMPRSS2-ERG fusions, but harbor distinct patterns of copy number aberrations. Here, we report that SPOP mutant prostate cancers also harbor increased numbers of genomic rearrangements, and functional data suggest that SPOP mutation alters repair of DNA double strand breaks (DSB).

Methods: We systematically investigated somatic alterations associated with genomic rearrangements, using a composite data set of 402 clinically localized prostate cancers. Functional analyses in vitro and in vivo were used to define pathways affected, and interrogate DNA repair phenotypes.

Results: In human prostate cancers, SPOP mutation is an early event specifically associated with increased intrachromosomal genomic rearrangements. Using a zebrafish model, SPOP mutation results in a transcriptional response consistent with BRCA1 inactivation, implicating altered repair of DSB. In vitro data suggest that SPOP participates in repair of DSB, and SPOP mutation impairs homology-directed repair (HDR), instead promoting error-prone non-homologous end joining (NHEJ). Finally, SPOP mutation sensitizes prostate cancer cells to DNA damaging therapeutic agents such as PARP inhibitors.

Conclusions: These results implicate SPOP as a novel participant in DSB repair, suggest that SPOP mutation drives prostate tumorigenesis in part through genomic instability, and indicate that SPOP mutant prostate cancer may be selectively responsive to DNA damaging therapeutics.

Citation Format: Christopher E. Barbieri, Gunther Boysen, Davide Prandi, Sung-Suk Chae, Arun Dahiya, Srilakshmi Nataraj, Mirjam Blattner, Clarisse Marotz, Limei Xu, Julie Huang, Paola Lecca, Sagar Chhangawala, Pengbo Zhou, Andrea Sboner, Francesca Demichelis, Yariv Houvras, Mark A. Rubin. SPOP mutation is associated with genomic instability in prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr NG01. doi:10.1158/1538-7445.AM2015-NG01

Abstract 3844: Targeting EZH2 in neuroendocrine prostate cancer

Background and aim of the study

EZH2 is the catalytic subunit of the Polycomb repressive complex 2 (PRC2) and it is involved in controlling gene expression through trimethylation of histone H3 lysine 27 (H3K27me3), a key mechanism that regulates chromatin structure and gene silencing. EZH2 is overexpressed in a wide range of cancers including prostate. Recent findings show that EZH2 can form a complex with the androgen receptor (AR), enhancing its transcriptional activity. However the role of EZH2 in AR low/negative prostate cancer has not been previously investigated. Long-term exposure to AR targeted therapies can cause an adaptive response mechanism in a subset of advanced prostate cancers. Often this adaptation is associated with loss of AR expression, clinical aggressiveness, and pathologic features of small cell or neuroendocrine carcinoma. This AR independent resistant phenotype is broadly termed neuroendocrine prostate cancer (NEPC). Initial studies from our lab have highlighted a landscape of genomic alterations that characterize NEPC. In this study we explore the hypothesis that the epigenetic modifier, EZH2, can lead the adaptive response towards an androgen-independent phenotype and towards NEPC.

Results

Using Next Generation RNA-sequencing, we profiled tumors from a cohort of patients including 20 NEPC, 68 Prostate Adenocarcinoma (PCa), and 19 castration resistant prostate cancer (CRPC) and we discovered that EZH2 is highly expressed in NEPC (characterized by low or absent AR and morphologic changes). These findings were also confirmed at protein level by immunohistochemistry. Based on the driving role of EZH2 in other tumor types and significant overexpression in NEPC tumors, we evaluated the effects of the EZH2 inhibitor, GSK343, in NEPC cells (NCI-H660) and PCa cells (LNCaP and DU145) in 3D Matrigel cultures. GSK343 effectively inhibited H3K27me3 and resulted in a significant reduction of NCI-H660 viability, measured with an ATP-based assay, whereas LNCaP and DU145 cells were minimally affected after 7 or 14 days of treatment. Using a custom designed Nanostring assay, we also demonstrated a significant increase in the expression of AR signaling genes (e.g. PSA, PSMA) and decrease in NEPC-associated genes (e.g. chromogranin A, AURKA, ENO2) when NEPC cells were treated with GSK343. These data suggest a modulation of the neuroendocrine phenotype via EZH2. We therefore extended these drug studies to patient-derived organoid models including both CRPC and NEPC organoids and we observed similar results with preferential sensitivity of the AR-negative NEPC organoids compared to AR-positive CRPC organoids and similar reversion of downstream AR/NEPC gene expression.

Conclusions

Altogether, these data suggest that EZH2-mediated epigenetic changes contribute to the AR-independent NEPC resistant phenotype, and this effect can be reverted or delayed by targeting EZH2 activity. EZH2 represents a promising drug target and a potential modulator of the NEPC phenotype.

Citation Format: Loredana Puca, Dong Gao, Myriam Kossai, Clarisse Marotz, Juan Miguel Mosquera, Theresa Y. MacDonald, Kyung Park, Rema Rao, Andrea Sboner, Yu Chen, Mark A. Rubin, Himisha Beltran. Targeting EZH2 in neuroendocrine prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3844. doi:10.1158/1538-7445.AM2015-3844