71. MGMT PROMOTER METHYLATION IS A PROGNOSTIC BIOMARKER IN EGFR MUTANT LUNG ADENOCARCINOMA WITH BRAIN METASTASES

EGFR-mutant lung adenocarcinomas (EGFRm-LUAD) have a higher risk of brain metastasis (BM) development than non-mutant lesions regardless of cancer stage. BM development is a marker of tumor aggressiveness and has significant prognostic impact that leads to treatment failure. MGMT promoter methylation is known to determine response to therapy in other cancer types but it has not been investigated in EGFRm-LUAD brain metastases. This work aims to assess whether MGMT promoter methylation predicts patient survival or BM development in EGFRm-LUAD patients. A large cohort of 90 primary EGFRm-LUAD, 33(37%) of which developed BM, were profiled using Illumina Infinium MethylationEPIC Beadchip. We utilized genome-wide methylation signatures to determine MGMT methylation status using the previously reported MGMT-STP27 approach that uses two CpG sites to predict MGMT methylation status. Cox modeling was performed to assess whether MGMT methylation status correlates with overall survival independent of other clinical factors. MGMT methylation significantly predicted poorer survival in EGFRm-LUAD patients developed BM (p=0.0003) and those who did not (p=0.003). A multivariate Cox analysis, adjusting for stage and smoking status as potential confounders, showed that MGMT methylation (HR=6.2, 95%CI:2.2–17.4, p=0.0005) and BM (HR=2.6, 95%CI:1.3–5.3, p=0.007) were both independently predictive of worsened survival. Total Mutation Burden calculated by the number of mutations per megabase of DNA was higher in MGMT methylated tumours with an interquartile range (IQR) of 58(30–71) compared to MGMT unmethylated tumours with IQR of 5.5(4.3–6.1). This work shows that MGMT promoter methylation status is an important prognostic biomarker in EGFRm-LUAD patients. Further work will validate these findings obtained using whole-genome DNA methylation by comparing to results using methylation specific PCR assays. MGMT promoter methylation status in EGFRm–LUAD patients with BM may be used to guide patient treatment with potentially a greater extent of treatment for those higher risk patients.

Implementation of PD-L1 22C3 IHC pharmDxTM in Cell Block Preparations of Lung Cancer: Concordance with Surgical Resections and Technical Validation of CytoLyt® Prefixation

BACKGROUND

Programmed death ligand-1 (PD-L1) assessed by immunohistochemistry (IHC) is used as biomarker for pembrolizumab therapy in advanced stage lung cancer patients. However, data permitting direct performance comparison between cytology and surgical specimen types are limited since both specimens from a single tumor site are infrequently available. In addition, alcohol fixation used with cytology specimens requires technical validation of the PD-L1 IHC assay before clinical use. We here report our experience with implementation of the PD-L1 22C3 IHC pharmDxTM assay for cytologic samples at a large tertiary cancer center.

STUDY DESIGN

Archival formalin-fixed (FF), paraffin-embedded cell blocks (CBs) and subsequent lung tumor resections (LTRs) from the same anatomical site were used for a direct comparison of PD-L1 tumor proportion scores (TPSs). TPS values were independently determined by one surgical lung pathologist and two cytopathologists blinded to the specimen pairs. An interim analysis was performed to facilitate the pooling of expertise among observers. After PD-L1 22C3 IHC pharmDxTM implementation for FF cytology specimens, dual-processed samples were used for a prospective technical validation of CytoLyt® prefixation (CF). Digital image analysis was performed for a subset of dual-processed specimens.

RESULTS

Eighty-one CBs and LTRs were included for comparison of the specimen types. PD-L1 assessment in CBs had an accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 88.9/72.8, 66.7/73.5, 95.2/72.3, 80.0/65.8, and 90.9/79.1% for the ≥50/≥1% cutoff, respectively. The intraclass correlation coefficient was 0.84 (95% confidence interval [CI]: 0.76, 0.90), and it improved after interim analysis (before: 0.79 and after: 0.92). The overall concordance between CF and FF for the categories defined by the ≥50/≥1% cutoff values was 90.4% (95% CI: 79.0, 96.8). Similar assay performance was confirmed by digital analysis.

CONCLUSIONS

PD-L1 22C3 IHC pharmDxTM shows good reliability if used with CB preparations. CF does not impact assay results significantly. Clinical validation with outcome data is needed, and digital methods of assessment should be further investigated.

Clinical implementation of circulating tumour DNA testing for EGFR T790M for detection of treatment resistance in non-small cell lung cancer

Aims

Epidermal growth factor receptor (EGFR) T790M mutations can be detected in the circulating tumour DNA from plasma of patients with non-small cell lung cancer (NSCLC) to triage patients for osimertinib eligibility and monitor patients longitudinally for development of T790M-mediated resistance.

Methods

Using droplet digital PCR (ddPCR), we examined the EGFR T790M status of 343 sequential patients with NSCLC and correlated mutational status with demographic and clinical features. Where available, serial T790M blood test results were assessed to identify clinical triggers and timing of repeat testing.

Results

Of the 343 patients with liquid biopsy test results, 24% were T790M positive. No clear clinical correlation with a T790M positive test result was identified in this study, although the number of metastatic sites did correlate significantly with the presence of EGFR sensitising mutations (L858R or exon 19 deletion) in patient plasma, as a measure of tumour DNA shedding. Of the 59 serial blood tests from patients that initially tested negative, 14% were positive on sequential testing, at a time interval up to 6 months after an initially negative blood test.

Conclusions

The ddPCR test for EGFR T790M mutations effectively triaged 24% of patients for treatment with osimertinib, avoiding the need for invasive tissue biopsy in these patients. Our findings suggest that initial and repeat ctDNA testing can be used to monitor for acquired EGFR T790M resistance for NSCLC.

BRAF V600E mutation and MET amplification as resistance pathways of the second-generation anaplastic lymphoma kinase (ALK) inhibitor alectinib in lung cancer

BACKGROUND

Anaplastic lymphoma kinase (ALK) targeted therapies have demonstrated remarkable efficacy in ALK-positive lung adenocarcinomas. However, patients inevitably develop resistance to such therapies. To investigate novel mechanisms of resistance to second generation ALK inhibitors, we characterized and modeled ALK inhibitor resistance of ALK-positive patient-derived xenograft (PDX) models established from advanced-stage lung adenocarcinoma patients who have progressed on one or more ALK inhibitors.

METHODS

Whole exome sequencing was performed to identify resistance mechanisms to ALK inhibitors in PDXs generated from biopsies at the time of relapse. ALK fusion status was confirmed using fluorescent in situ hybridization, immunohistochemistry, RNA-sequencing, RT-qPCR and western blot. Targeted therapies to overcome acquired resistance were then tested on the PDX models.

RESULTS

Three PDX models were successfully established from biopsies of two patients who had progressed on crizotinib and/or alectinib. The PDX models recapitulated the histology and ALK status of their patient tumors, as well as their matched patients' clinical treatment outcome to ALK inhibitors. Whole exome sequencing identified MET amplification and previously unreported BRAF V600E mutation as independent mechanisms of resistance to alectinib. Importantly, PDX treatment of inhibitors specific for these targets combined with ALK inhibitor overcame resistance.

CONCLUSIONS

Bypass signaling pathway through c-MET and BRAF are independent mechanisms of resistance to alectinib. Individualized intervention against these resistance pathways could be viable therapeutic options in alectinib-refractory lung adenocarcinoma.

Case studies of the radical cation reactivity in meso-aryl and octaethyl porphyrins

The reactivity of porphyrin radical cationic species derived from octaethyl porphyrin (OEP) or meso-aryl porphyrins with nucleophiles, envisioned as an access route to elaborate porphyrin dimers, has been studied and optimized in the case of OEP. Standardized conditions have been applied to various spacers to show that the success of the reaction is mostly nucleophile dependent and that the method has little chances to yield non-linear bis-porphyrins.

Determining the unmet survivorship needs in patients with head and neck cancer: A prospective, longitudinal study

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Background: Head and neck cancer patients commonly have unmet needs. Our purpose was to determine the number, type, and predictors of unmet survivorship needs in patients with head and neck cancer over their cancer journey. Methods: Patients with primary, non-metastatic head and neck cancer were prospectively enrolled prior to curative intent treatment (surgery, radiation and or systemic therapy in any combination). Patients completed baseline demographics, the Cancer Survivors' Unmet Needs Measure (CaSUN) and the FACT-HN and then again 3, and 6 months post-treatment. Mean unmet needs at each time point were calculated. Univariable and stepwise multivariable analyses of predictors for number of unmet needs were performed at each time point. Results: Among 187 participants, median age was 64 (31-88) and 148 (79%) were male. Education was beyond high school in 117 (63%) and 63 (41%) were working at diagnosis. Most patients had oropharynx (n = 84; 46%), hypopharynx/larynx (n = 40; 22%) or oral cavity (n = 28;15%) cancers. At least one unmet need was reported by 68%, 52%, and 56% at baseline, 3 and 6 months. The mean number of unmet needs was 7.5 ± 9.1 at baseline, 3.8 ± 6 at 3 months and 5.4 ± 8.5 at 6 months. Higher education level [3.24 (0.24,6.24); p = 0.035] and worse QOL [-0.14 (-0.22,-0.06); p < 0.01] were associated with increased survivorship unmet needs on multivariable analysis at baseline. Worse QOL was associated with increased survivorship unmet needs on multivariable analysis at 3 [-0.21 (-0.31,-0.12); p < 0.01] and 6 months [-0.27 (-0.49,-0.06); p < 0.01]. Table describes the top unmet needs. Conclusions: A high proportion of patients with head and neck cancer have unmet needs, more commonly in patients with poorer quality of life. Post-treatment, unmet needs were more often related to treatment toxicities and their impact on quality of life. [Table: see text]

Genomic analysis of driver-negative lung adenocarcinoma (LA) in lifetime never smokers

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Background: Genomic events giving rise to driver negative LA in never smokers remain elusive. Here we report results of whole exome sequencing (WES) and targeted RNA sequencing in NS who had no mutation drivers found on routine clinical testing by targeted next generation sequencing (NGS). Methods: The cohort of never smokers with EGFR/ALK negative LA by clinical biomarker testing at Princess Margaret Cancer Centre, were first subjected to various clinical NGS profiling platforms (table). Where tissue was available, those negative for potential drivers in the clinical NGS then underwent WES (mean coverage > 200x) and Oncomine comprehensive v.3 RNA sequencing. We analyzed mutational signatures (MS) of the driver negative cohort based on the COSMIC catalog and assessed the median tumor mutation burden (mTMB mut/Mb -Megabase) in cases without a smoking MS, to avoid confounders. Results: Of 159 never smokers profiled with clinical NGS, potential drivers were found in 86 (54%): 75 (87%) with mutations in known LA driver genes and 11 (13%) with fusions. Among the remaining never smokers that tested negative by clinical NGS, 35 (48%) had available tissue for further testing. The Oncomine panel identified 9 cases (25%) with fusions or MET exon14 mutation (n = 7). Within the driver negative group, 24 (92%) underwent WES. Three tumors had WES base substitution patterns that were consistent with a smoking-related MS (MS4). Twenty-one patients exhibited signatures found common across all cancer types (MS 5), associated with DNA mismatch repair (MS 6, MS 20) or APOBEC over-activation (MS 2, MS13). In the driver-negative group, we identified 7 pts with somatic mutations in the KMT2 family (4 KMT2C, 4 KMT2A, 1 KMT2D), known for putative tumor suppressors and histone methyltransferases. mTMB on the driver negative group was 1.92, while one outlier with APOBEC MS and KMT2C/A mutations had a TMB of 16.8. Conclusions: Never smokers with driver negative LA are a heterogeneous group, with different MS and a wide TMB range. Mutations on KMT2 family are frequently found in driver negative LA in never smokers and warrant further investigations. [Table: see text]

Determination of Patulin in Apple Juice by Liquid Chromatography: Collaborative Study

An AOAC International-International Union of Pure and Applied Chemistry-International Fruit Juice Union (AOAC-IUPAC-IFJU) collaborative study was conducted to evaluate a liquid chromatographic (LC) procedure for determination of patulin in apple juice. Patulin is a mold metabolite found naturally in rotting apples. Patulin is extracted with ethyl acetate, treated with sodium carbonate solution, and determined by reversed-phase LC with UV detection at 254 or 276 nm. Water, water-tetrahydrofuran, or water-acetonitrile was used as mobile phase. Levels determined in spiked test samples were 20, 50,100, and 200 μg/L. A test sample naturally contaminated at 31 μg/L was also included. Twenty-two collaborators in 10 countries analyzed 12 test samples of apple juice. Recoveries averaged 96%, with a range of 91-108%. Repeatability relative standard deviations (RSDr) ranged from 10.9 to 53.8%. The reproducibility relative standard deviation (RSDR) ranged from 15.1 to 68.8%. The LC method for determination of patulin in apple juice has been adopted first action by AOAC INTERNATIONAL.

Public perceptions of non-pharmaceutical interventions for influenza and mosquito-borne illnesses - a statewide survey in Arizona

AIMS

We conducted a statewide online survey to understand public knowledge, attitudes, and practices (KAP) related to non-pharmaceutical interventions (NPIs) for mosquito-borne diseases and influenza in Arizona.

METHODS

The survey included knowledge of diseases, major health concerns, and sources of health information and KAP of NPIs for influenza and mosquito-borne diseases. Our team worked with Qualtrics^®, an online survey company, to recruit a representative sample of 1500 adults in Arizona.

RESULTS

Of the 1531 respondents who completed the survey, most indicated that chronic conditions were their primary health concern (48%), with the other half split between infectious diseases (25%) and health effects of environmental conditions (26%). The majority (88%) of respondents indicated that they use the Internet to get their health information. Approximately one in eight people reported not emptying standing water and reducing potential mosquito habitats, despite respondents citing them as being the most effective factors in reducing mosquitoes. Regarding specific diseases, about half of the respondents were concerned about West Nile virus and/or Zika virus. Most (85%) people knew the signs and symptoms of influenza and 63% of people reported being likely to get the influenza shot. Those who did not vaccinate (n = 285) reported concerns that the vaccine would make them sick (41%), was ineffective (37%), or others indicated, 'I don't want to' (37%).

CONCLUSIONS

Overall, respondents were most concerned with chronic conditions and received their information from the Internet. Knowledge about mosquito-borne diseases was low. There were high levels of acceptance and self-reported uptake of the influenza vaccine.

Determination of Total Vitamin C in Fruit Juices and Related Products by Liquid Chromatography: Interlaboratory Study

A interlaboratory study was conducted to evaluate a liquid chromatographic (LC) procedure for the determination of total vitamin C in foods at levels of 5–60 mg/100 g. Emphasis was placed on fruit juices, although selected foods were also included in the study. Following dissolution of sample in water, endogenous dehydroascorbic acid was converted to ascorbic acid by precolumn reduction with dithiothreitol at neutral pH. Total ascorbate was determined by C18 reversed-phase LC with a phosphate eluent at pH 2.5, incorporating dithiothreitol to maintain vitamin C in the reduced form, and UV detection at 254 nm. Seven types of fruit juices and foods were tested by 19 collaborators in 7 countries. Three duplicate juices and foods met the criteria for Youden pairs and yielded repeatability relative standard deviation of 5.80–14.66%. Reproducibility relative standard deviation ranged from 6.36 to 35.54% (n = 10) with HORRAT values of 0.82–4.04. The LC method is suitable for routine use in fruit products and foods containing &gt;5 mg/100 g vitamin C and is recommended for further validation by AOAC INTERNATIONAL and International Fruit Juice Union.

CMET-30. COMPREHENSIVE METHYLOME ANALYSIS OF EGFR-MUTANT PRIMARY LUNG ADENOCARCINOMA AND MATCHED BRAIN METASTASIS

Brain metastasis (BM) in patients with EGFR-mutant lung adenocarcinoma is a major determinant of overall survival. Novel insight into the genetic and epigenetic underpinnings of BM development is lacking. The aim of this study is to compare the methylome of EGFR-mutant primary lung adenocarcinoma (EGFRM-PLA) and matched BM to identify important alterations for the mechanisms of BM. Matched EGFRM-PLA and BM tumors from seven patients were profiled using the Illumina Infinium MethylationEPIC BeadChip array. Unsupervised clustering analyses of the 14 samples showed a similar whole DNA methylation signatures between EGFRM-PLA and BM tumors. Furthermore, PCA plot highlighted that seven matched BM and lung tumor samples were clustered together closely based on matching pairs for the most variable probes (2.5K to 10K). These observations indicate high level of concordance and the same cell of origin. However, these fourteen samples clustered into two groups based on tumor site being lung or brain based on 83K differentially methylated CpG sites. Of the 83K probes, 2.4K were either hypermethylated or hypomethylated in all lung samples. A quarter of these 2.4K probes were located in promoter regions. Specifically, we identified differences in methylation status of EGFR/ALK promoter regions in lung tumors versus BM. CNV analyses showed higher deep deletions of chromosomes and genes in BM compared to EGFRM-PLA. Leukocytes unmethylation for purity (LUMP) scores which indicate immune cell infiltration were similar between lung and BM pairs (Mean LUMP_score=0.64) consistent with high immune cell infiltration. Our results indicated a similar whole DNA methylation signature of EGFRM-PLA and matched BM, while comprehensive analysis identified important differentially methylated probes. Distinct differences in CNV alterations were observed in lung versus brain samples. The BM and EGFRM-PLA showed similar tumor purity and immune cell components. Overall, tumor methylation profiling provides clinically important information regarding biology of BM in EGFRM-PLA.

BSCI-26. COMPARATIVE METHYLATION PROFILING OF EGFR MUTANT LUNG ADENOCARCINOMA AND PAIRED BRAIN METASTASIS

BACKGROUND: Adenocarcinomas (ADC) are the most common lung tumours and EGFR-mutant lesions have a higher risk of brain metastasis development, which confers poorer survival. Genetic and epigenetic signatures of brain metastasis have not been comprehensively identified. The aim of this study is to compare the methylome of EGFR-mutant primary lung tumor and matched brain metastasis to identify mechanisms of brain metastasis and new treatment targets. METHOD: Seven matched primary to brain metastasis tumours were profiled using the Illumina Infinium MethylationEPIC BeadChip array. Hierarchical clustering and principal component analyses (PCA) were performed using most variable CpG sites. Supervised analyses were performed between lung and brain tumour samples. Copy number variation (CNV) plots identified alterations between pairs along with Leukocytes unmethylation for purity (LUMP) score and prediction lymphocyte proportion analyses to measure immune infiltration. RESULTS: Unsupervised clustering showed that the fourteen tumours clustered according to patient with similar methylation profiles between each of seven matched pairs. On the supervised analysis using 83K significant CpG sites, the fourteen samples clustered into two groups based on tumour site being lung or brain. Of these 83K CpG sites, 2.4K were either hypermethylated or hypomethylated in all lung samples. One quarter of these 2.4K CpG sites were located in promoter regions. CNV analyses showed losses of FGFR1, C19MC, CDKN2A, PTCH1, and MYCN genes with higher deep deletions in brain versus lung primary samples. Immune infiltration measures were similar between lung and brain metastasis pairs (LUMP-score=0.64) consistent with high immune cell infiltration. CONCLUSION: In this EGFR-mutant lung adenocarcinomas and matched brain metastases, differentially methylated CpG sites and CNV alterations are identified that distinguish lung from brain samples. Further work with additional matched samples may further elucidate signatures specific to brain metastasis and aid in our understanding of the mechanisms of brain metastasis.

Evaluation and Classification of Physical and Psychological Stress in Firefighters using Heart Rate Variability

Stress detection has a huge potential for disease prevention and management, and to improve the quality of life of people. Also, work safety can be improved if stress is timely and reliably detected. The availability of low-cost consumer wearable devices that monitor vital-signs, gives access to stress detection schemes. Heart rate variability (HRV), a stress-related vital-sign, was derived from wearable device data to reliably determine stress-levels. In order to build and train a deployable stress-detector, we collected labeled HRV data in controlled environments, where subjects were exposed to physical, psychological and combined stress. We then applied machine learning to separate and identify the different stress types and understand the relationship with HRV data. The resulting C5 decision tree model is capable of identifying the stress type with 88% accuracy, in a 1-minute time window. For the first time physical and psychological stress can be distinguished with a 1-minute time resolution from smoke-divers, firefighters, who enter high-risk environments to rescue people, and experience intense physical and psychological stress. To improve our model, we created an integrated system to acquire expert labels in real-time from firefighters during their training in a Rescue Maze. A next goal is to transfer the algorithms into generic systems for monitoring and coaching high-risk professionals to improve their stress resilience during training and reduce their risk in the field.

Clinical, pathological and genetic predictors of patient-derived xenograft (PDX) engraftment in EGFR-mutated lung adenocarcinoma (LUAD)

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Background: PDX are useful preclinical models to study drug response and resistance. Different specimen types have been used to generate PDX models including histological (surgery and CT-guided biopsy) and cytological preparations (EBUS and pleural effusions). We hypothesize that engraftment is not stochastic and is affected by many factors including sample type and tumor pathological and molecular properties. To improve sample selection and cost-effectiveness of PDX experiments, we investigated clinical, histological and genetic correlates of engraftment in EGFR-mutated LUAD. Methods: We assessed PDX engraftment from 96 surgical resections, 13 CT-guided biopsies, 21 EBUS and 14 pleural effusions of EGFR-mutated LUAD. Sixty-five samples, including 6 engrafted (XG) and 54 non-engrafted (noXG) were evaluated by exome sequencing. Results: Engraftment was successful in 9/96 (9%) surgical resections, 6/13 (46%) CT-guided biopsies, and 0/35 cytological samples. Biopsies taken at time of treatment failure (compared to treatment naive biopsies) correlated with greater engraftment (p=0.007, AUC = 0.68). Multivariable regression analysis of clinical variables at the time of sampling identified advanced (vs early) stage (p = 0.003) and histological (vs cytological) preparations (p < 0.001) as the strongest predictors of engraftment (AUC = 0.79). Among tumor histologic features, solid (vs lepidic, acinar and papillary) pattern was associated with greater engraftment (p < 0.001). Presence of EGFR-T790M (p = 0.004) and TP53 (p = 0.009) mutations were associated with greater engraftment; all XG samples carried TP53 mutations. EGFR-Ex19del (p = 0.076) showed a trend towards engraftment whereas EGFR-L858R (p = 0.086) trended towards non-engraftment. Conclusions: Advanced stage, post-therapy tumors, T790M+ and TP53+ EGFR-mutated LUAD samples obtained for histological processing are more likely to engraft as PDXs. Despite low engraftment rates, these models are useful to study novel therapeutic strategy and elucidation of resistance mechanisms.

Quantifying EpCAM heterogeneity of circulating-tumor-cells (CTCs) from small cell lung cancer (SCLC) patients

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Background: Tumor heterogeneity and evolution of SCLC is poorly defined. Serial longitudinal interrogation of tumor heterogeneity from CTCs detected in peripheral blood patient (pt) samples is a potential strategy to address this gap in knowledge. However, existing technology is generally limited to the capture and enumeration of CTCs, without a high-throughput method to quantify phenotypic properties. Here, we evaluated a novel nanotechnology platform – nanoparticle-mediated magnetic ranking cytometry (MagRC) to profile SCLC CTCs by EpCAM protein expression. Methods: Blood samples from 20 SCLC pts were processed through the MagRC platform. Magnetic nanoparticles conjugated with anti-EpCAM antibodies were incubated with whole blood samples then introduced into the MagRC device where CTCs are sorted by differently sized nickel micromagnets within microfluidic channels. Captured CTCs are ranked into 8 zones that correlate with EpCAM expression levels (zone 1 = highest to 8 = lowest). For 8 pts, all samples were processed at a 1mL/hr flow rate (fr), and for 12 pts, a 0.5mL/hr fr was also studied; 66% of all chips were processed at a 1ml/hr fr and 34% at a 0.5ml/hr fr. The average zone for each chip was compared to the flow rate, age, and stage (extensive-stage (ES) vs limited-stage (LS)). The differences were tested using the Wald test within the linear mixed effects model. Results: Among 20 pts, 11 were ES; 9 were LS. Median age at diagnosis was 69 years old (yo); 65% were male. We detected CTCs in 12 of 20 pts (60%), similar to other studies. When comparing the MagRC-ranked EpCAM zone, the 0.5mL/hr fr demonstrated a lower median zone (4.3 vs 6.5; p < 0.001) as compared to the 1mL/hr rate. Interestingly, pts > 65 yo had a higher median zone (6.2 vs. 3.5; p = 0.019) compared to those ≤65 yo. The effect remained significant after controlling for flow rate (p = 0.002). No EpCAM zone difference was detected between ES and LS. Conclusions: We demonstrate the ability of MagRC to quantify EpCAM expression levels of CTCs from SCLC pts. We observed a higher MagRC zone (i.e. lower EpCAM expression) from pts > 65 yo. This observation requires validation in larger datasets along with continued investigation into the biology of SCLC CTCs.

Methylation profiling of EGFR mutant primary and metastatic lung cancer with brain metastasis

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Background: EGFR-mutant lung cancer is a key molecular subtype of lung cancer. In recent years there is clear recognition in the value of using methylation signature of cancer for improving diagnosis and predicting outcome as well as understanding the biology of cancer progression. Methods: In this study we chose to characterize the methylome signature of early stage surgically resected EGFR-mutant lung adenocarcinomas in the primary lung tumor. 90 NSCLC cases and 7 matched metastatic brain samples were profiled using Illumina Infinium MethylationEPIC Beadchip. We compared methylation profiles of 1) smokers versus lifetime non-smokers and 2) matched primary lung versus brain metastasis to identify methylation biomarkers. We performed supervised analysis and unsupervised clustering of the methylation data. Results: Unsupervised clustering of all lung and brain samples based on 10K most variable probes showed a similar methylation signature between metastatic brain samples and lung samples. The 7-matched brain and lung samples formed close cluster groups based on matching pairs for the most variable probes from 2.5K to 10K, reflecting the same cell of origin. Supervised analysis of smokers versus lifetime non-smokers did not show any significant methylation differences between the two groups, while unsupervised analysis did not create clusters of smokers and non-smokers based on various number of probe sets we analyzed. Conclusions: Lung tumors that metastasized to the brain share similar methylation features with primary lung tumors. Comprehensive methylation profiling demonstrated no difference between EGFR mutant tumors in smokers versus non-smokers, suggesting that the EGFR mutation is a stronger determinant of outcome independent of smoking.

Antagonizing Retinoic Acid-Related-Orphan Receptor Gamma Activity Blocks the T Helper 17/Interleukin-17 Pathway Leading to Attenuated Pro-inflammatory Human Keratinocyte and Skin Responses

The nuclear hormone receptor retinoic acid receptor-related-orphan-receptor-gamma t (RORγt) is the key transcription factor required for Th17 cell differentiation and for production of IL-17 family cytokines by innate and adaptive immune cells. Dysregulated Th17 immune responses have been associated with the pathogenesis of several inflammatory and autoimmune diseases such as psoriasis, psoriatic arthritis, and ankylosing spondylitis. In this article, we describe the in vitro pharmacology of a potent and selective low molecular weight RORγt inhibitor identified after a structure-based hit-to-lead optimization effort. The compound interfered with co-activator binding to the RORγt ligand binding domain and impaired the transcriptional activity of RORγt as evidenced by blocked IL-17A secretion and RORE-mediated transactivation of a luciferase reporter gene. The inhibitor effectively reduced IL-17A production by human naive and memory T-cells and attenuated transcription of pro-inflammatory Th17 signature genes, such as IL17F, IL22, IL26, IL23R, and CCR6. The compound selectively suppressed the Th17/IL-17 pathway and did not interfere with polarization of other T helper cell lineages. Furthermore, the inhibitor was selective for RORγt and did not modify the transcriptional activity of the closely related family members RORα and RORβ. Using human keratinocytes cultured with supernatants from compound treated Th17 cells we showed that pharmacological inhibition of RORγt translated to suppressed IL-17-regulated gene expression in keratinocyte cell cultures. Furthermore, in ex vivo immersion skin cultures our RORγt inhibitor suppressed IL-17A production by Th17-skewed skin resident cells which correlated with reduced human β defensin 2 expression in the skin. Our data suggests that inhibiting RORγt transcriptional activity by a low molecular weight inhibitor may hold utility for the treatment of Th17/IL-17-mediated skin pathologies.

Meningioma Screening With MRI in Childhood Leukemia Survivors Treated With Cranial Radiation

PURPOSE

Radiation-induced meningioma is a known late effect of cranial radiation therapy. Cranial magnetic resonance imaging (MRI) can detect small meningiomas, but its potential value as a screening tool is unknown.

METHODS AND MATERIALS

MRI was used to screen asymptomatic survivors of childhood acute lymphoblastic leukemia (ALL) treated with cranial radiation therapy ≥10 years previously. The incidence of radiation-induced meningioma and outcomes of this group were compared with a historical cohort of survivors with the same exposure who underwent imaging only to investigate clinical signs or symptoms.

RESULTS

One hundred seventy-six childhood leukemia survivors were included in this study: 70 in the screening group and 106 unscreened. Screening MRI was performed a median of 25 years after radiation therapy and detected meningioma in 15 (21.4%). In the unscreened group, 17 patients (16.0%) had neurologic symptoms leading to an MRI a median interval of 24 years after radiation therapy, 9 of whom (8.5%) were diagnosed with meningioma. There was no significant difference between screened versus unscreened patients in the size of meningioma (mean diameter, 1.6 cm vs 2.6 cm; P = .13), meningioma incidence (7.4% vs 4.0% at 25 years; P = .19), or extent of resection. Three patients had persistent neurologic symptoms in the unscreened group versus none among screened patients (P = .28).

CONCLUSIONS

Screening MRI was able to detect small meningiomas that were not clinically apparent; however, we could not demonstrate a significant improvement in the chance of total resection or a significant decrease in morbidity. A larger sample could clarify potential reduction in neurologic sequelae associated with screening.

Evaluation of a hepatitis C clinical care coordination programme's effect on treatment initiation and cure: A surveillance-based propensity score matching approach

Hepatitis C (HCV) is a viral infection that if left untreated can severely damage the liver. Project INSPIRE was a 3 year HCV care coordination programme in New York City (NYC) that aimed to address barriers to treatment initiation and cure by providing patients with supportive services and health promotion. We examined whether enrolment in Project INSPIRE was associated with differences in HCV treatment and cure compared with a demographically similar group not enrolled in the programme. INSPIRE participants in 2015 were matched with a cohort of HCV-infected persons identified in the NYC surveillance registry, using full optimal matching on propensity scores and stratified by INSPIRE enrolment status. Conditional logistic regression was used to assess group differences in the two treatment outcomes. Two follow-up sensitivity analyses using individual pair-matched sets and the full unadjusted cohort were also conducted. Treatment was initiated by 72% (790/1130) of INSPIRE participants and 36% (11 960/32 819) of study-eligible controls. Among initiators, 65% (514/790) of INSPIRE participants compared with 47% (5641/11 960) of controls achieved cure. In the matched analysis, enrolment in INSPIRE increased the odds of treatment initiation (OR: 5.25, 95% CI: 4.47-6.17) and cure (OR: 2.52, 95% CI: 2.00-3.16). Results from the sensitivity analyses showed agreement with the results from the full optimal match. Participation in the HCV care coordination programme significantly increased the probability of treatment initiation and cure, demonstrating that care coordination for HCV-infected individuals improves treatment outcomes.

A physical assessment tool to evaluate functional status compared to ECOG scores in cancer outpatients

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Background: Individuals with cancer may experience loss of function, disability and fatigue. There is interest in team-based functional and physical assessment as part of a comprehensive oncology care plan. The Bellarmine Norton Assessment Tool (BNAT) was developed to provide an objective physical assessment tool for interprofessional use. The purpose of this study was to evaluate the BNAT and correlate its outcomes with ECOG scores across groups diagnosed with pancreatic (P), breast (B) and lung (L) cancers. Methods: The BNAT was developed by the Bellarmine University Physical Therapy Program utilizing validated physical assessment tests. It consists of 1 subjective question about physical activity frequency followed by 4 objective tests: 2-Minute Step Test (2MST), 30 Sec Sit-to-Stand, Timed Arm Curl (TAC) and Timed Up and Go. The ECOG was administered by attending oncologists during the same visit as BNAT testing. 18 participants were identified 6 in each of the diagnosis groups from a recruitment cohort of 57. The avg. age for P was 68.8±9 yrs 4♀,2♂; B 71.5±15.8 yrs 6♀; L 65.0±12.4 yrs 3♀,3♂. Results: The combined mean ± SD ECOG score was 1.2±1.0 (range 0-3) while the combined BNAT score was 15.4±6.5 (range 7-29). Mean BNAT score by diagnosis: P 16.6±7.4; B 13.0±5.5; & L 18.3±5.7. Spearman correlation analysis of BNAT and ECOG scores revealed a significant (p = 0.0001) negative correlation of agreement (r = -0.79). Both B and L cancers had significant (p < 0.05) correlation of agreement (B r = -0.71 & L r = -0.88). TAC correlation to ECOG was strongest in L group (r = -0.86), but 2MST was strongest for P group (r = -0.62). There was a reciprocal relationship of slopes between TAC and 2MST based on diagnosis. L steepest slope in TAC (-6.2 with deviation from 0, p = 0.014) while P had steepest slope with 2MST (-13.1). Slope for B group consistently fell between the 2 other diagnoses. Conclusions: There was a strong linear relationship of BNAT, TAC & 2MST to ECOG scores across the 3 cohorts of diagnoses. The BNAT subcomponents have varying degrees of contribution to the total that can be attributed to diagnosis-related functional deficits, thus giving providers information to determine appropriate care.

Associations between asthma trigger reports, mental health conditions, and asthma morbidity among world trade center rescue and recovery workers

Aim: There is limited information regarding asthma triggers in World Trade Center (WTC) rescue and recovery workers (RRW) or how mental health conditions affect the perception of triggers. Methods: We included 372 WTC workers with asthma. The Asthma Trigger Inventory (ATI) assessed triggers along five domains: psychological, allergens, physical activity, infection, and pollution. We administered the Structured Clinical Interview to diagnose post-traumatic stress disorder (PTSD), major depression and panic disorder (PD). The Asthma Control Questionnaire (ACQ) and Mini Asthma Quality of Life Questionnaire (AQLQ) measured asthma control and quality of life, respectively. Linear regression models were fitted to examine the association of ATI total and subdomain scores with mental health conditions as well as the percent of ACQ and AQLQ variance explained by ATI subscales. Results: The most common triggers were air pollution (75%) and general allergens (68%). PTSD was significantly associated with psychological triggers (partial r²=0.05, p < 0.01), physical activity (partial r²=0.03, p < 0.01) and air pollution (partial r²=0.02, p = 0.04) subscales while PD was significantly associated with air pollution (partial r²=0.03, p = 0.03) and general allergens (partial r²=0.02, p = 0.03). ATI subscales explained a large percentage of variance in asthma control (r²=0.37, p < 0.01) and quality of life scores (r²=0.40, p < 0.01). Psychological subscale scores explained the largest portion of the total variability in ACQ (partial r²= 0.11, p = 0.72) and AQLQ (partial r²=0.14, p = 0.64) scores. Conclusion: RRW with mental health conditions reported more asthma triggers and these triggers were associated with asthma morbidity. These data can help support interventions in RRW with asthma.

Metal-mediated linear self-assembly of porphyrins

Porphyrin derivatives are highly relevant to biological processes such as light harvesting and charge separation. Their aromatic electronic structure and their accessible HOMO-LUMO gap render porphyrins highly attractive for the development of opto- and electro-active materials. Due to the often difficult covalent synthesis of multiporphyrins, self-assembly using metal complexation as the driving force can lead to well defined objects exhibiting a controlled morphology, which will be required to analyse and understand the electronic properties of porphyrin wires. This article presents two assembly approaches, namely by peripheral coordination or by binding to a metal ion in the porphyrin core, that are efficient and well designed for future developments requiring interactions with a surface.