COVID-19 Stroke Apical Lung Examination Study 2: a national prospective CTA biomarker study of the lung apices, in patients presenting with suspected acute stroke (COVID SALES 2)

BACKGROUND

Apical ground-glass opacification (GGO) identified on CT angiography (CTA) performed for suspected acute stroke was developed in 2020 as a coronavirus-disease-2019 (COVID-19) diagnostic and prognostic biomarker in a retrospective study during the first wave of COVID-19.

OBJECTIVE

To prospectively validate whether GGO on CTA performed for suspected acute stroke is a reliable COVID-19 diagnostic and prognostic biomarker and whether it is reliable for COVID-19 vaccinated patients.

METHODS

In this prospective, pragmatic, national, multi-center validation study performed at 13 sites, we captured study data consecutively in patients undergoing CTA for suspected acute stroke from January-March 2021. Demographic and clinical features associated with stroke and COVID-19 were incorporated. The primary outcome was the likelihood of reverse-transcriptase-polymerase-chain-reaction swab-test-confirmed COVID-19 using the GGO biomarker. Secondary outcomes investigated were functional status at discharge and survival analyses at 30 and 90 days. Univariate and multivariable statistical analyses were employed.

RESULTS

CTAs from 1,111 patients were analyzed, with apical GGO identified in 8.5 % during a period of high COVID-19 prevalence. GGO showed good inter-rater reliability (Fleiss κ = 0.77); and high COVID-19 specificity (93.7 %, 91.8-95.2) and negative predictive value (NPV; 97.8 %, 96.5-98.6). In subgroup analysis of vaccinated patients, GGO remained a good diagnostic biomarker (specificity 93.1 %, 89.8-95.5; NPV 99.7 %, 98.3-100.0). Patients with COVID-19 were more likely to have higher stroke score (NIHSS (mean +/- SD) 6.9 +/- 6.9, COVID-19 negative, 9.7 +/- 9.0, COVID-19 positive; p = 0.01), carotid occlusions (6.2 % negative, 14.9 % positive; p = 0.02), and larger infarcts on presentation CT (ASPECTS 9.4 +/- 1.5, COVID-19 negative, 8.6 +/- 2.4, COVID-19 positive; p = 0.00). After multivariable logistic regression, GGO (odds ratio 15.7, 6.2-40.1), myalgia (8.9, 2.1-38.2) and higher core body temperature (1.9, 1.1-3.2) were independent COVID-19 predictors. GGO was associated with worse functional outcome on discharge and worse survival after univariate analysis. However, after adjustment for factors including stroke severity, GGO was not independently predictive of functional outcome or mortality.

CONCLUSION

Apical GGO on CTA performed for patients with suspected acute stroke is a reliable diagnostic biomarker for COVID-19, which in combination with clinical features may be useful in COVID-19 triage.

Circulating tumor cells reveal early predictors of disease progression in patients with stage III NSCLC undergoing chemoradiation and immunotherapy

Circulating tumor cells (CTCs) are early signs of metastasis and can be used to monitor disease progression well before radiological detection by imaging. Using an ultrasensitive graphene oxide microfluidic chip nanotechnology built with graphene oxide sheets, we were able to demonstrate that CTCs can be specifically isolated and molecularly characterized to predict future progression in patients with stage III non-small cell lung cancer (NSCLC). We analyzed CTCs from 26 patients at six time points throughout the treatment course of chemoradiation followed by immune checkpoint inhibitor immunotherapy. We observed that CTCs decreased significantly during treatment, where a larger decrease in CTCs predicted a significantly longer progression-free survival time. Durvalumab-treated patients who have future progression were observed to have sustained higher programmed death ligand 1+ CTCs compared to stable patients. Gene expression profiling revealed phenotypically aggressive CTCs during chemoradiation. By using emerging innovative bioengineering approaches, we successfully show that CTCs are potential biomarkers to monitor and predict patient outcomes in patients with stage III NSCLC.

Amivantamab plus chemotherapy with and without lazertinib in EGFR-mutant advanced NSCLC after disease progression on osimertinib: primary results from the phase III MARIPOSA-2 study

BACKGROUND

Amivantamab plus carboplatin-pemetrexed (chemotherapy) with and without lazertinib demonstrated antitumor activity in patients with refractory epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC) in phase I studies. These combinations were evaluated in a global phase III trial.

PATIENTS AND METHODS

A total of 657 patients with EGFR-mutated (exon 19 deletions or L858R) locally advanced or metastatic NSCLC after disease progression on osimertinib were randomized 2 : 2 : 1 to receive amivantamab-lazertinib-chemotherapy, chemotherapy, or amivantamab-chemotherapy. The dual primary endpoints were progression-free survival (PFS) of amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy. During the study, hematologic toxicities observed in the amivantamab-lazertinib-chemotherapy arm necessitated a regimen change to start lazertinib after carboplatin completion.

RESULTS

All baseline characteristics were well balanced across the three arms, including by history of brain metastases and prior brain radiation. PFS was significantly longer for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy [hazard ratio (HR) for disease progression or death 0.48 and 0.44, respectively; P < 0.001 for both; median of 6.3 and 8.3 versus 4.2 months, respectively]. Consistent PFS results were seen by investigator assessment (HR for disease progression or death 0.41 and 0.38 for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy, respectively; P < 0.001 for both; median of 8.2 and 8.3 versus 4.2 months, respectively). Objective response rate was significantly higher for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (64% and 63% versus 36%, respectively; P < 0.001 for both). Median intracranial PFS was 12.5 and 12.8 versus 8.3 months for amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy versus chemotherapy (HR for intracranial disease progression or death 0.55 and 0.58, respectively). Predominant adverse events (AEs) in the amivantamab-containing regimens were hematologic, EGFR-, and MET-related toxicities. Amivantamab-chemotherapy had lower rates of hematologic AEs than amivantamab-lazertinib-chemotherapy.

CONCLUSIONS

Amivantamab-chemotherapy and amivantamab-lazertinib-chemotherapy improved PFS and intracranial PFS versus chemotherapy in a population with limited options after disease progression on osimertinib. Longer follow-up is needed for the modified amivantamab-lazertinib-chemotherapy regimen.

Pre-processing Applied to Instrumental Data in Analytical Chemistry: A Brief Review of the Methods and Examples

The field of analytical chemistry has been significantly advanced by the availability of state-of-the-art instrumentation, allowing for the development of novel applications in this field. However, in many cases, the direct interpretation of the recorded data is often not straightforward, hence some level of pre-processing is required (e.g., baseline correction, derivatives, normalization, smoothing). These techniques have become a critical first step for the successful analysis of the data recorded, and it is recommended to use them before the application of chemometrics (e.g., classification, calibration development). The aim of this paper is to provide with an overview of the most used pre-processing methods applied to instrumental analytical methods (e.g., spectroscopy, chromatography). Examples of their application in near infrared and UV-VIS spectroscopy as well as in gas chromatography will be also discussed. Overall, this paper provides with a comprehensive understanding of pre-processing techniques in analytical chemistry, highlighting their importance during the analysis and interpretation of data, as well as during the development of accurate and reliable chemometric models.

Abstract 5581: Single-cell genomic analysis of patient-derived circulating tumor cells in pancreatic cancer

Metastatic pancreatic cancer suffers from an extremely low five-year survival rate of only 3%. While patients with localized disease show marginally better survival rates, 52% of pancreatic cancers are not diagnosed until metastases have already developed. There is therefore a critically unmet need in the early diagnoses of pancreatic cancer patients. Liquid biopsies have emerged as a promising tool for cancer diagnosis through the analysis of various blood-based biomarkers. Among these, circulating tumor cells (CTCs) stand out as a promising target of interest. Over the past decade, CTCs have been identified as a precursor to metastasis. CTCs have also been shown to harbor mutations matching those of the primary tumor, making them a potential surrogate for biopsied tissue. However, CTCs are an extremely heterogenous population of cells, making bulk analysis challenging. In this study, we demonstrate a workflow for the isolation and genomic characterization of single CTCs from pancreatic cancer patients. CTCs are first enriched using a size-based microfluidic system, the Labyrinth, developed in the Nagrath lab. Single CTCs are subsequently isolated using the DEPArray Nxt system, followed by whole genome amplification (WGA) and low-pass sequencing. The pipeline was optimized using three commercially available pancreatic cancer cells lines (Panc-1, Capan-2, and BxPC-3) and two pancreatic cancer CTC cell lines previously developed in-house (CTC-CL-1 and CTC-CL-2). Finally, the workflow was validated using a blood sample from a stage IV pancreatic ductal adenocarcinoma patient. Following WGA, the average nucleic material concentration of the cell lines was 26.24 ± 16.28 ng/μL and 14.43 ng/μL for cells isolated from the patient sample. The average fragment size was 746 ± 232.79 bp for cell line cells and 507 bp for patient sample cells. This was within the expected range of 100-2000 bp. Both CTC cell lines show gains on parts of chromosome 8q (Myc), 10q (FGFR2) and 17q. Myc is a known oncogene and FGFR2 has been associated with cell growth, migration, and invasion. There are also noticeable differences between the two CTC-CL-1 cells, with one cell showing a 3p12.3-3p26.3 gain (CTNNB1), and the other showing a loss of 6q12-6q15 and gain of 6q16.1-6q27 (Myb, ESR1). A patient sample CTC and patient-matched WBC were isolated and sequenced. The CTC has a noticeable gain of chromosome 1q and loss of chromosome 5q. A gain in chromosome 1q has been seen previously in pancreatic cancer and chromosome 5q is the location of multiple oncogenes including APC, CSF1R and FGFR4. The loss of APC is known to affect Wnt/β-catenin signaling, causing an increase in CD34 expression which is linked to increase in cell invasion and migration. These results demonstrate an efficient workflow for the single cell genomic analysis of pancreatic CTCs. Further studies can be conducted to characterize the heterogenous landscape of CTCs in pancreatic cancer.

Citation Format: Harrison Ball, Brittany Rupp, Sarah Owen, Kaylee Smith, Valerie Gunchick, Evan T. Keller, Vaibhav Sahai, Sunitha Nagrath. Single-cell genomic analysis of patient-derived circulating tumor cells in pancreatic cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5581.

Molecular imaging of experimental atherosclerosis using anti-malondialdehyde-modified low-density lipoprotein humanised antibody fragment targeted nanoparticles

Introduction

Oxidative modification of low-density lipoprotein (LDL), for example by malondialdehyde (MDA) adduction with subsequent uptake by macrophages to form foam cells and later the plaque necrotic core, is a key initiating event in atherogenesis. Accordingly, a larger lipid necrotic core is a key plaque vulnerability factor, predisposing plaques to rupture and subsequent thrombosis and development of an acute coronary syndrome. Thus, MDA-LDL is an attractive focus for the molecular targeting of atherosclerotic plaques.

Purpose

To develop antibody fragment-targeted nanoparticles that can be utilised for both the molecular imaging and therapeutics of vulnerable atherosclerotic plaques.

Methods

LO1 is an IgG3k natural monoclonal murine antibody that reacts with MDA-LDL. Humanised LO1Fab fragments have been engineered to reduce immunogenicity and improve lesion penetration. These humanised LO1Fab fragments were used to functionalise fluorescent poly(lactic-co-glycolic acid) (PLGA) - polyethylene glycol (PEG) nanoparticles. Nanoparticle in vitro function was assessed, prior to fluorescence molecular tomography (FMT) co-registered with micro-CT, four-hours after iv injection in atherosclerotic LDL-receptor−/− mice fed a high-fat diet for 40-weeks.

Results

Humanised LO1Fab fragment conjugated fluorescent PLGA-PEG nanoparticles were formulated with 210nm size and polydispersity index (variability of nanoparticle size around the average) of &lt;0.2. Antibody conjugation efficiency was 30%. In vitro function was confirmed on ELISA versus the blank untargeted nanoparticles with MDA-LDL on solid phase, detecting nanoparticle presence via the conjugated LO1Fab, PEG corona or fluorescence. Fluorescence microscopy on stained aortic root cryosections from atherosclerotic mice confirmed binding to fatty lesions. Construct in vivo in half-life was 90-minutes for both the targeted and untargeted nanoparticles in a two-phase model in LDL-receptor−/− mice, based on fluorescence analysis of serial tail vein blood samples. There was greater uptake in the region-of-interest (heart and aortic arch vessels) in mice injected with LO1Fab-conjugated nanoparticles versus untargeted nanoparticles (mean ± standard deviation) (64.7±22.9 versus 25.2±26.5pmol of Cy5; n=7; p=0.02). Ex vivo analysis fluorescence reflectance imaging and quantitative FMT of the extracted aortae confirmed these findings (1.0±0.3 versus 0.5±0.2pmol of Cy5; n=7; p=0.002; Figure 1).

Conclusions

Humanised antibody Fab fragment fluorescent nanoparticles have been developed that successfully target MDA-LDL and localise to atherosclerotic plaques in murine experimental atherosclerosis. These targeted nanoparticles have the potential to amplify fluorescent signal for imaging and carry a therapeutic cargo for targeted drug delivery direct to atherosclerotic plaques.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Wellcome Trust Clinical Research Fellowship

Metabolic collateral lethal target identification reveals MTHFD2 paralogue dependency in ovarian cancer

Recurrent loss-of-function deletions cause frequent inactivation of tumour suppressor genes but often also involve the collateral deletion of essential genes in chromosomal proximity, engendering dependence on paralogues that maintain similar function. Although these paralogues are attractive anticancer targets, no methodology exists to uncover such collateral lethal genes. Here we report a framework for collateral lethal gene identification via metabolic fluxes, CLIM, and use it to reveal MTHFD2 as a collateral lethal gene in UQCR11-deleted ovarian tumours. We show that MTHFD2 has a non-canonical oxidative function to provide mitochondrial NAD+, and demonstrate the regulation of systemic metabolic activity by the paralogue metabolic pathway maintaining metabolic flux compensation. This UQCR11-MTHFD2 collateral lethality is confirmed in vivo, with MTHFD2 inhibition leading to complete remission of UQCR11-deleted ovarian tumours. Using CLIM's machine learning and genome-scale metabolic flux analysis, we elucidate the broad efficacy of targeting MTHFD2 despite distinct cancer genetic profiles co-occurring with UQCR11 deletion and irrespective of stromal compositions of tumours.

Integrated Workflow for the Label-Free Isolation and Genomic Analysis of Single Circulating Tumor Cells in Pancreatic Cancer

As pancreatic cancer is the third deadliest cancer in the U.S., the ability to study genetic alterations is necessary to provide further insight into potentially targetable regions for cancer treatment. Circulating tumor cells (CTCs) represent an especially aggressive subset of cancer cells, capable of causing metastasis and progressing the disease. Here, we present the Labyrinth-DEPArray pipeline for the isolation and analysis of single CTCs. Established cell lines, patient-derived CTC cell lines and freshly isolated CTCs were recovered and sequenced to reveal single-cell copy number variations (CNVs). The resulting CNV profiles of established cell lines showed concordance with previously reported data and highlight several gains and losses of cancer-related genes such as FGFR3 and GNAS. The novel sequencing of patient-derived CTC cell lines showed gains in chromosome 8q, 10q and 17q across both CTC cell lines. The pipeline was used to process and isolate single cells from a metastatic pancreatic cancer patient revealing a gain of chromosome 1q and a loss of chromosome 5q. Overall, the Labyrinth-DEPArray pipeline offers a validated workflow combining the benefits of antigen-free CTC isolation with single cell genomic analysis.

Epidermal Growth Factor Receptor Mutations Carried in Extracellular Vesicle-Derived Cargo Mirror Disease Status in Metastatic Non-small Cell Lung Cancer

In non-small cell lung cancer (NSCLC), identifying the presence of sensitizing and resistance epidermal growth factor receptor (EGFR) mutations dictates treatment plans. Extracellular vesicles (EVs) are emerging as abundant, stable potential liquid biopsy targets that offer the potential to quantify EGFR mutations in NSCLC patients at the RNA and protein level at multiple points through treatment. In this study, we present a systematic approach for serial mutation profiling of 34 EV samples from 10 metastatic NSCLC patients with known EGFR mutations through treatment. Using western blot and droplet digital PCR (ddPCR), sensitizing (exon 19 deletion, L858R) mutations were detected in EV-Protein, and both sensitizing and resistance (T790M) mutations were quantified in EV-RNA. EGFR mutations were detected in EV-Protein from four patients at multiple time points through treatment. Using EV-RNA, tumor biopsy matched sensitizing mutations were detected in 90% of patients and resistance mutations in 100% of patients. Finally, mutation burden in EV-RNA at each time point was compared to disease status, described as either stable or progressing. For 6/7 patients who were longitudinally monitored through treatment, EV mutation burden mirrored clinical trajectory. When comparing mutation detection between EV-RNA and ctDNA using ddPCR, EVs had a better detection rate for exon 19 deletions and the L858R point mutation. In conclusion, this study demonstrates that integrating EV analysis into liquid biopsy mutation screening has the potential to advance beyond the current standard of care "rule in" test. The multi-analyte testing allows future integration of EGFR mutation monitoring with additional EV-markers for a comprehensive patient monitoring biomarker.

On-Chip Biogenesis of Circulating NK Cell-Derived Exosomes in Non-Small Cell Lung Cancer Exhibits Antitumoral Activity

As the recognition between natural killer (NK) cells and cancer cells does not require antigen presentation, NK cells are being actively studied for use in adoptive cell therapies in the rapidly evolving armamentarium of cancer immunotherapy. In addition to utilizing NK cells, recent studies have shown that exosomes derived from NK cells also exhibit antitumor properties. Furthermore, these NK cell-derived exosomes exhibit higher stability, greater modification potentials and less immunogenicity compared to NK cells. Therefore, technologies that allow highly sensitive and specific isolation of NK cells and NK cell-derived exosomes can enable personalized NK-mediated cancer therapeutics in the future. Here, a novel microfluidic system to collect patient-specific NK cells and on-chip biogenesis of NK-exosomes is proposed. In a small cohort of non-small cell lung cancer (NSCLC) patients, both NK cells and circulating tumor cells (CTCs) were isolated, and it is found NSCLC patients have high numbers of NK and NK-exosomes compared with healthy donors, and these concentrations show a trend of positive and negative correlations with bloodborne CTC numbers, respectively. It is further demonstrated that the NK-exosomes harvested from NK-graphene oxide chip exhibit cytotoxic effect on CTCs. This versatile system is expected to be used for patient-specific NK-based immunotherapies along with CTCs for potential prognostic/diagnostic applications.

Simultaneous Single Cell Gene Expression and EGFR Mutation Analysis of Circulating Tumor Cells Reveals Distinct Phenotypes in NSCLC

While cancer cell populations are known to be highly heterogeneous within a tumor, the current gold standard of tumor profiling is through a tumor biopsy. These biopsies are invasive and prone to missing these clones due to spatial heterogeneity, and this bulk analysis approach can miss information from rare subpopulations. To noninvasively investigate tumor cell heterogeneity, a streamlined workflow is developed to scrutinize rare cells, such as circulating tumor cells (CTCs), for simultaneous analysis of mutations and gene expression profiles at the single cell level. This powerful workflow overcomes low-input limitations of single cell analysis techniques. The utility of this multiplexed workflow to unravel inter- and intra-patient heterogeneity is demonstrated using non-small-cell lung cancer (NSCLC) CTCs (n = 58) from six epidermal growth factor receptor (EGFR) mutant positive NSCLC patients. CTCs are isolated using a high-throughput microfluidic technology, the Labyrinth, and their EGFR mutation status and gene expression profiles are characterized.

Tumour-reprogrammed stromal BCAT1 fuels branched-chain ketoacid dependency in stromal-rich PDAC tumours

Branched-chain amino acids (BCAAs) supply both carbon and nitrogen in pancreatic cancers, and increased levels of BCAAs have been associated with increased risk of pancreatic ductal adenocarcinomas (PDACs). It remains unclear, however, how stromal cells regulate BCAA metabolism in PDAC cells and how mutualistic determinants control BCAA metabolism in the tumour milieu. Here, we show distinct catabolic, oxidative and protein turnover fluxes between cancer-associated fibroblasts (CAFs) and cancer cells, and a marked reliance on branched-chain α-ketoacid (BCKA) in PDAC cells in stroma-rich tumours. We report that cancer-induced stromal reprogramming fuels this BCKA demand. The TGF-β-SMAD5 axis directly targets BCAT1 in CAFs and dictates internalization of the extracellular matrix from the tumour microenvironment to supply amino-acid precursors for BCKA secretion by CAFs. The in vitro results were corroborated with circulating tumour cells (CTCs) and PDAC tissue slices derived from people with PDAC. Our findings reveal therapeutically actionable targets in pancreatic stromal and cancer cells.

Abstract B37: Analysis of non-small cell lung cancer (NSCLC) circulating biomarkers for monitoring early response to radiation therapy

Approximately 20% of non-small cell lung cancer (NSCLC) patients will be diagnosed with stage 3 cancer, with a predicted survival rate between 20-30%. Stage 3 NSCLC patients commonly undergo chemoradiation treatment, with imaging scans being the standard of care for determining tumor control or progression both during and after radiation treatment. Imaging technologies can only show progression after it has occurred, making treatment challenging. We suggest that the molecular characterization of biomarkers found in the bloodstream can identify or predict radiation treatment efficacy before progression becomes visible on a scan. In this study, patients undergo a response-driven adaptive radiation therapy (RDART) protocol: four weeks of chemoradiation followed by a set of imaging scans before an additional 2 weeks of adapted, personalized radiation with chemotherapy. In this work, we provide combined analysis of both circulating tumor cells (CTCs), a rare cell found in a patient’s peripheral blood, and exosomes, nanovesicles excreted from cells, for use in assessing radiation efficacy. Our initial cohort is 30 patients, and we aimed to collect six timepoints: one pretreatment, two during radiation treatment, and three after radiation treatment. In this study, we look at the changes in several characteristics: CTC counts, PD-L1 expression on CTCs, as well as gene expression changes of both CTCs and exosomes using Affymetrix microarrays. CTCs were isolated using a graphene oxide (GO)-based microfluidic device and were found to be present in all pretreatment samples and most following samples. Initial transcriptome profiling of 5 patients using microarrays highlighted clustered gene expression differences for both CTCs and exosomes when comparing pretreatment samples with those collected during radiation.

Citation Format: Emma Purcell, Zeqi Niu, Madeline Grzesik, Sarah Owen, Heather Fairbairn, Shruti Jolly, Sunitha Nagrath. Analysis of non-small cell lung cancer (NSCLC) circulating biomarkers for monitoring early response to radiation therapy [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr B37.

Abstract B36: Identifying single-cell gene expression and EGFR mutation profile heterogeneity in NSCLC patients’ CTCs

The efficacy of targeted therapies was first shown in patients with non-small cell lung cancer (NSCLC) who possess activating epidermal growth factor receptor (EGFR) mutations that responded to tyrosine kinase inhibitors (TKIs). Current standard of care is to screen metastatic patients for the presence of EGFR mutations to determine if they qualify for TKI treatment. Due to the invasiveness of a tumor biopsy, this characterization is typically only done at the time of diagnosis. This single time-point determines the entire treatment plan. Despite strong initial response to TKI therapy, most patients develop resistance within months, most commonly by acquiring a secondary EGFR mutation. Identifying resistance through current monitoring techniques, such as measuring tumor volume, can lead to a delay in detection. Alternatively, circulating tumor cells (CTCs) are cancer cells present in the blood that provide access to tumor cells without the requirement of a biopsy. Shed from the tumor into the vasculature, CTCs circulate throughout the body before a fraction extravasate, leading to metastatic sites. CTCs have been shown to carry tumor-matched characteristics in both genotype and phenotype. Due to their ease of access, they can be used to serially track patients’ conditions to detect the early emergence of new tumor clones and, potentially, therapeutic resistance. One of the major limitations of CTCs’ clinical utility is their low abundance in the blood. Our group previously developed the Labyrinth, a high-throughput, label-free microfluidic technology, which enables rapid and efficient CTC enrichment. These CTCs are used for enumeration or single-cell transcriptomic analysis. Initial single-cell analysis was performed through highly multiplexed RT-qPCR that compared 96-gene expression profiles to unravel inter- and intrapatient CTC heterogeneity. We recently developed a complimentary single-cell analysis approach using digital PCR (dPCR) to detect the presence of sensitizing EGFR mutations, exon 19 deletion and L858R, and resistance mutation, T790M. dPCR is an ultrasensitive approach with single-molecule resolution, which enables detection and quantification at a single-cell level by partitioning the sample into individual PCR reaction droplets. This resolution can distinguish if a cell is homo- or heterozygous for a mutation and each allele’s relative expression level. We validated this system for single-cell analysis using lung cancer cell lines and demonstrated its agreement with qPCR results. We present initial findings of EGFR mutation screening in CTCs from a small cohort of NSCLC patients with known EGFR status. We highlight the single-cell heterogeneity of CTCs within a patient at both the gene expression and EGFR mutation level. By tracking these patients’ CTCs over time, we may be able to identify the emergence of resistant clones sooner than can be done in the clinic. This may allow for more rapid treatment modification and lead to improved patient outcomes.

Citation Format: Sarah Owen, Ting-Wen Lo, Shamileh Fouladdel, Mina Zeinali, Evan Keller, Ebrahim Azizi, Nithya Ramnath, Sunitha Nagrath. Identifying single-cell gene expression and EGFR mutation profile heterogeneity in NSCLC patients’ CTCs [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr B36.

Expansion of Circulating Tumor Cells from Patients with Locally Advanced Pancreatic Cancer Enable Patient Derived Xenografts and Functional Studies for Personalized Medicine

Improvement in pancreatic cancer treatment represents an urgent medical goal that has been hampered by the lack of predictive biomarkers. Circulating Tumor Cells (CTCs) may be able to overcome this issue by allowing the monitoring of therapeutic response and tumor aggressiveness through ex vivo expansion. The successful expansion of CTCs is challenging, due to their low numbers in blood and the high abundance of blood cells. Here, we explored the utility of pancreatic CTC cultures as a preclinical model for treatment response. CTCs were isolated from ten patients with locally advanced pancreatic cancer using the Labyrinth, a biomarker independent, size based, inertial microfluidic separation device. Three patient-derived CTC samples were successfully expanded in adherent and spheroid cultures. Molecular and functional characterization was performed on the expanded CTC lines. CTC lines exhibited KRAS mutations, consistent with pancreatic cancers. Additionally, we evaluated take rate and metastatic potential in vivo and examined the utility of CTC lines for cytotoxicity assays. Patient derived expanded CTCs successfully generated patient derived xenograft (PDX) models with a 100% take rate. Our results demonstrate that CTC cultures are possible and provide a valuable resource for translational pancreatic cancer research, while also providing meaningful insight into the development of distant metastasis, as well as treatment resistance.

TNF-derived peptides inhibit tumour growth and metastasis through cytolytic effects on tumour lymphatics

Tumour necrosis factor (TNF) is a multi-functional cytokine with profound and diverse effects on physiology and pathology. Identifying the molecular determinants underlying the functions and pathogenic effects of TNF is key to understanding its mechanisms of action and identifying new therapeutic opportunities based on this important molecule. Previously, we showed that some evolutionarily conserved peptides derived from TNF could induce cell death (e.g. apoptosis and/or necrosis), a feature of immune defence mechanisms shared by many vertebrates. In this study, we demonstrated that necrosis-inducing peptide P16 kills human glioblastoma cancer cells and primary human hepatoma or renal cancer cells isolated from patients who had not responded to standard treatments. Importantly, we show that the necrosis-inducing peptide P1516 significantly improves survival by inhibiting tumour metastasis in a 4T1 breast cancer syngeneic graft mouse model. Because the lymphatic system is an important metastatic route in many cancers, we also tested the effect of TNF-derived peptides on monolayers of primary human lymphatic endothelial cells (hDLEC) and found that they increased junctional permeability by inducing cytoskeletal reorganization, gap junction formation and cell death. Transmission electron microscopy imaging evidence, structural analysis and in-vitro liposome leakage experiments strongly suggest that this killing is due to the cytolytic nature of these peptides. P1516 provides another example of a pro-cytotoxic TNF peptide that probably functions as a cryptic necrotic factor released by TNF degradation. Its ability to inhibit tumour metastasis and improve survival may form the basis of a novel approach to cancer therapy.

Abstract 407: Gene expression and mutation profiles of single lung circulating tumor cells

In the era of personalized medicine, many targeted therapies have been developed against cancer-specific antigens, which have greatly improved patient outcome. The efficacy of targeted therapies was first shown in patients with non-small cell lung cancer (NSCLC) containing activating epidermal growth factor receptor (EGFR) mutations who responded to tyrosine kinase inhibitors (TKIs). To determine if a patient qualifies for targeted therapy, the patient must undergo a tumor biopsy. Usually done at the time of diagnosis, this single time-point examination dictates the treatment plan. Despite strong initial response to TKI therapy, nearly all patients develop resistance, most commonly by acquiring a secondary EGFR mutation. At the time of halted response, an additional biopsy may be necessary to screen for the presence of these secondary, resistance-causing mutations.

Circulating tumor cells (CTCs) are cancer cells present in the blood that provide an alternative to an invasive tumor biopsy. Shed from the primary tumor, CTCs circulate throughout the vasculature, and extravasate leading to metastasis. CTCs have been shown to carry tumor-matched characteristics in both genotype and phenotype. Easily accessed through a blood draw, they can be used to serially track patients throughout treatment to detect the early emergence of new tumor clones.

One of the biggest hurdles with CTCs being clinical prognostic markers is their low abundance in the blood. We have previously developed a high-throughput, label-free microfluidic technology, the Labyrinth, to isolate CTCs from the blood of breast, lung, and pancreatic cancer patients. This technology allows for quick and efficient isolation of CTCs from the millions of surrounding blood cells. After isolation, the CTCs are used for enumeration or single cell analysis. The single cell gene expression analysis performs a highly multiplexed RT-qPCR of a pre-designed 96 gene panel.

Here we report a complementary single cell analysis approach to detect the presence of EGFR point mutations, L858R and T790M, implicated in TKI response using digital PCR (dPCR). dPCR is a highly sensitive approach which enables detection and quantification a single-cell level. dPCR relies on small sample loading and partitions the sample into individual PCR reaction droplets. This single molecule resolution provides the ability to distinguish if a cell is homo- or heterozygous for a mutation as well as their relative expression levels. We have validated this system for single cell analysis using lung cancer cell lines with known L858R and T790M mutation status. We present initial findings of EGFR mutation screening of lung CTCs from patients with known EGFR status based on tissue profiling.

By tracking patients over time, comparing the CTC profiles, and correlating it to patient outcomes, we may be able to better identify early treatment resistant clones and adjust their treatment to improve patient outcome.

Citation Format: Sarah Owen, Ting-Wen Lo, Shamileh Fouladdel, Ebrahim Azizi, Nithya Ramnath, Sunitha Nagrath. Gene expression and mutation profiles of single lung circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 407.

Abstract P2-01-08: The potential role of CTNND1 (catenin (cadherin-associated protein), Delta 1) in breast cancer bone metastasis

Background:

The bone is a frequently visited site by breast cancer cells. Most women who die of metastatic breast cancer would already have bone metastases, whether they are micro- or macro-metastases. Metastatic bone metastasis from breast cancer is mostly osteolytic, with reasons unclear and little in vitro and in vivo studies exploring the osteolytic nature of bone metastasis. In the present study, we investigated the potential role of CTNND1, Catenin (Cadherin-Associated Protein) Delta 1, in the context of bone metastasis of breast cancer.

Materials and Methods:

In order to identify potential genes involved in bone metastasis, we established a novel in vitro model named Bone Matrix Extract (BME) which was extracted from human femur and used to mimic the bone environment. Full profile of gene expression in response to BME was conducted using Ampliseq technology. Potential genes associated with bone metastasis was examined in a clinical breast cohort containing both cancer and normal tissues (n = 103), collected immediately following surgery. Gene transcript levels were quantified using QPCR and analysed against patient's pathological information and clinical outcome. We generated a series of cell models by knocking down and over-expressing one of the most relevant genes, CTNND1, using siRNA, sh-RNA, ribozyme transgenes and insertion of full coding sequence containing plasmids. Function assays including Matrigel based-adhesion, cancer cell-osteobalstic cell contact, proliferation, transwell invasion and migration were used to investigate the changes of biological features after interfering with CTNND1 expression in relation to BME / co-culture models.

Results:

CTNND1 was down regulated in all breast epithelial cells following BME treatment at both mRNA and protein level. From the clinical cohort, we found that compared with benign tissue, breast cancer tissues had significantly decreased CTNND1 transcript expression. Reduced CTNND1 was associated with advanced TNM stage and poor distant metastasis, local recurrence and bone metastasis. We went on to knockdown CTNND1 by siRNA, ribozyme as well as lenti-shCTNND1 transfection in MCF-10A and MDA-231 cells and overexpressed CTNND1 in MCF-7 cells. In vitro study demonstrated that knockdown of CTNND1 expression led to decreased capacity of Matrigel-adhesion, migration and invasion but increased cancer cell-osteobalstic cell adhesion. No effects were observed on cell proliferation after altering CTNND1 expression, in the presence or absence of BME.

Conclusions:

In this initial study on CTNND1 in breast cancer, our current data suggests that lower transcript expression of CTNND1 associates with a poorer patient prognosis. CTNND1 reduction may play a role in the progression of breast cancer bone metastasis.

Citation Format: Gong C, Andrew A, Feng Y, Owen S, Liang G, Davies E, Song E, Jiang W. The potential role of CTNND1 (catenin (cadherin-associated protein), Delta 1) in breast cancer bone metastasis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-01-08.

Real-world benefit of nivolumab in a Canadian non-small-cell lung cancer cohort

Background

Nivolumab was the first immuno-oncology agent available for the treatment of lung cancer in Canada. In the present study, we evaluated the real-world benefit of nivolumab in Canadian patients with lung cancer.

Methods

Patients included in the cohort were identified from a registry of patients treated through expanded access to nivolumab before and after Health Canada approval. Demographics were collected from the application forms. Outcome data for the duration of treatment and survival were collected retrospectively.

Results

In contrast to the randomized clinical trial populations, our study cohort included patients who were older (median age: 66 years; range: 36-92 years) and who had an Eastern Cooperative Oncology Group performance status of 2 (8.9%). Despite the poorer-prognosis cohort, median overall survival was 12.0 months, which is comparable to the survival demonstrated in the randomized phase iii trials of nivolumab in lung cancer. Median time to treatment discontinuation was 3.45 months and was similar for all patient subgroups, including poorer-prognosis groups such as those with a performance status of 2, those 75 years of age and older, and those with brain metastases.

Conclusions

Nivolumab given in a real-world clinical setting was associated with results similar to those reported in the phase iii clinical trial setting.

Perceived interviewee anxiety and performance in telephone interviews

Purpose

The purpose of this paper is to focus on the role of interviewee anxiety as a predictor of perceived hireability (Study 1, n=82) and job suitability (Study 2, n=74).

Design/methodology/approach

Using an experimental design, participants were randomly allocated to one of two conditions (an audio recording of either a confident or anxious job candidate with identical scripts) and asked to take the role of an interviewer.

Findings

The anxious interviewee (played by an actor) was consistently rated as less hireable (in a combined sample based on Studies and 2), less suitable to the job and received less favorable hiring recommendations (as assessed in Study 2) than the confident interviewee (played by the same actor).

Research limitations/implications

The study was conducted with students who may have less interview experience than experienced interviewers.

Practical implications

The results suggest that anxiety has a negative biasing effect on perceived hireability and job suitability ratings. In other words, the behavioral manipulation of anxiety affects hireability ratings, independent of any subjective assessment of anxiety.

Originality/value

The findings provide evidence of an anxiety bias in telephone interview settings. The results highlight the importance of considering anxiety cues when training employment interviewers.

Abstract 2803: Novel auristatins with high activity on efflux-positive models and demonstrable bystander activity

Auristatins are a class of clinically validated antimitotic agents utilized as payloads in antibody-drug conjugates (ADCs). Auristatins display many of the desirable properties necessary for ADC cytotoxins, such as low nanomolar potency, cell permeability, and activity across multidrug-resistant (MDR+) cell lines. Herein, we report the development of novel auristatins, which have a unique combination of these favorable properties. The hydrophilic monomethyl auristatin F (MMAF) was chosen as the parent structure, and a medicinal chemistry campaign was undertaken to functionalize various sites of the auristatin with hydrophobic moieties in an effort to improve membrane permeability. The structure-activity relationships (SAR) of the new auristatins demonstrated clear trends correlating hydrophobicity, structure, and polarity with permeability and in vitro cytotoxicity. The highest-performing molecules showed a preference for hydrophobic functionalization at the N-terminal dolavaline. The payloads were linked to the C-terminal position of the auristatin with a lysosomally cleavable maleimido-dipeptide linker. Examination of the ADCs revealed low ng/mL activity in CD30+ and CD19+ cell lines in vitro. Anti-CD70 ADCs demonstrated high in vivo efficacy in a 786-O xenograft and complete remissions (CRs) in the efflux-positive renal cell carcinoma model. Anti-CD30 ADCs were dosed in a CD30+ and CD30- admixed Karpas/Karpas-35R xenograft model to demonstrate proof-of-concept in vivo bystander activity. In summary, these novel auristatins showed potential across multiple indications as ADC payloads.

Citation Format: Philip N. Moquist, Tim D. Bovee, Andrew B. Waight, Sarah Owen, Jamie A. Mitchell, Margo Zaval, Marsha Quick, Sharsti Sandall, Kim K. Emmerton, Nicole Blesie, Robert P. Lyon, Peter Senter, Svetlana Doronina. Novel auristatins with high activity on efflux-positive models and demonstrable bystander activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2803.

Abstract 5577: Single cell mutation and gene expression co-analysis of lung circulating tumor cells

With the aim of personalized medicine, there have been many targeted therapies developed against cancer-specific antigens. The efficacy of targeted therapies was first shown in lung cancer patients containing activating epidermal growth factor receptor (EGFR) mutations who responded to tyrosine kinase inhibitors. Despite the promise of these EGFR targeted therapies, lung cancer patients routinely acquire an additional EGFR mutation, T790M, which causes treatment resistance. In order to determine if a patient qualifies for targeted therapy, they must get an invasive tumor biopsy, and may require a second biopsy if they stop responding to treatment. Circulating tumor cells (CTCs) are shed from the primary tumor into the bloodstream, a fraction of which lead to the development of metastases. CTCs can be isolated from a minimally-invasive blood draw, termed a “liquid-biopsy”, and their increased presence in the blood correlates with poor patient prognosis. CTCs present an approach to track and screen patients during treatment to determine if they acquire new mutations or other aggressive cell phenotypes. CTCs have been shown to be highly heterogeneous, existing in phenotypic states across the entire epithelial to mesenchymal transition spectrum as well as contain both primary tumor matched and unmatched mutations. We have previously established a workflow for the isolation and single cell characterization of CTCs. CTCs are isolated from the blood using a novel high-throughput inertial microfluidic device, the Labyrinth. This device has been optimized using cancer cell lines across many cancer types and has been used to process hundreds of blood samples from breast, lung, and pancreatic cancer patients for CTC enumeration. After CTC isolation using the Labyrinth, single cell suspensions are generated for lysis and RT-qPCR for up to 96 single cells using a 96-gene panel. Here we present initial results for the incorporation of mutation screening on the same single cells using digital PCR (dPCR). dPCR relies on small sample quantity to load one target molecule per reaction droplet for end-point PCR analysis. Due to its single molecule resolution, it has increased sensitivity compared to other traditional PCR methods, making it an ideal platform for single cell mutation screening. This enables us to determine if the cell is homo- or heterozygous, as well as quantify the relative expression in heterozygous mutations. We have validated the technology for single cell mutation detection of EGFR mutations, L858R and T790M, in addition to other genes such as TP53 and KRAS. The specificity of the EGFR mutation detection assays was confirmed using lung cancer cell line H1975, which is known to carry these two heterozygous mutations. Ultimately, the ability to couple single cell mutation and gene expression analysis using CTCs may allow oncologists to better monitor treatment response to guide the use and duration of targeted therapies.

Citation Format: Sarah Owen, Ting-Wen Lo, Shamileh Fouladdel, Ebrahim Azizi, Sunitha Nagrath. Single cell mutation and gene expression co-analysis of lung circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5577.

Abstract P3-07-07: The pan-HER inhibitor, neratinib and wingless-type MMTVs (Wnt)/Wnt regulators in human breast cancer; a biological and clinical perspective

Background. Neratinib is an orally available tyrosine kinase inhibitor that irreversibly binds and inhibits EGFR, HER2 and HER4 receptor tyrosine kinases. Neratinib has been shown to have clinical activity in HER2-amplified or overexpressed breast cancers and those with HER2 mutations. However, there are indications that it may also work on other subtypes that are not strongly positive for the receptors. The present study first screened the effects of neratinib on a range of kinase targets and identified that the Wnt signalling components are key factors that allow neratinib to interact and targets. These targets were also validated in a cohort of human breast cancer.

Methods. Human breast cancer cohorts (n=124) were tested for the transcript expression of HER family including EGFR, HER2, HER3 and HER4 and a number of Wnt family members and the Wnt signalling regulators, ie. GSK3, Axin-1, Axin-2 and β-catenin. The expression patterns were analysed against the clinicopathological and survival status of the patients. Neratinib was tested on a panel of breast cancer cell lines including triple negative cells for the effects on cytoxicity, cell growth, matrix adhesiveness and cellular migration. Signalling kinase pathways were screened using an antibody based kinase array. The effect of neratinib on multiple protein kinases was tested on the cell models, together with other kinase inhibitors.

Results. Neratinib had an inhibitory effect on the cellular migration and cell-matrix adhesiveness of breast cancers at non-toxic concentrations, an effect more profound with MCF-7 and T47D cell lines than with BT20 and MDA MB-231 which are negative for the ER/EGFR/HER2 receptors. Of the multiple kinase inhibitors tested, neratinib was found to exert inhibition on cell function in synergy with the Wnt/β-catenin inhibitor (FK535) and GSK3 inhibitor (TWS119). The expression of the HER and Wnt family members, Wnt Inhibitory Factor-1 and Wnt regulators varied in mammary and breast cancer tissues and in their correlation with the clinicopathological factors. Of the aberrantly expressed receptors, Wnts and Wnt regulators, HER-2 and 4 were found to significantly correlate with Wnt10b (p&lt;0.05), EGFR/HER1 was found significantly correlated with GSK3 (p&lt;0.05) and HER-3 with Wnt5a (p&lt;0.03). Furthermore, we identified that the integrated expression pattern of five of these factors, namely EGFR, HER2, HER4, Wnt5 and Wnt Inhibitory Factor-1 formed an expression signature that were significantly linked to the overall survival (survival time 148±3.7 vs 113.7 ±7.5 months for favourable and non-favourable pattern, respectively, p=0.002) and disease free survival (p=0.004) of the patients (median follow-up 120 months)

Conclusion. Neratinib, at non-toxic concentration levels, is a profound inhibitor of the migration and matrix adhesion of breast cancer cells, cell functions linked to the aggressiveness and metastasis of breast cancer cells. Its synergistic effects with the Wnt and GSK3 inhibitor, together with the prognostic value of the HER family/Wnt, indicate that the Wnt pathway together with the HER family forms a new molecular indicator and target when considering neratinib in the treatment patients with breast cancer.

Citation Format: Owen S, Ruge F, Lalani AS, Avogadri-Connors F, Bryce RP, Davies E, Jiang WG. The pan-HER inhibitor, neratinib and wingless-type MMTVs (Wnt)/Wnt regulators in human breast cancer; a biological and clinical perspective [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-07-07.

Abstract P4-05-03: Heat shock protein 27 (HSP27) and HER2 positively correlate in breast cancer and effect cell responsiveness to neratinib and cMET inhibitor

Background: Upregulation of heat shock protein-27 (HSP27), a key member of the HSP family, has been shown to confer resistance to chemotherapy and radiotherapy in solid tumours including breast cancer. Evidence is also emerging that HSP27 is linked to the metastatic spread of breast cancer and key cellular traits including cellular migration. Neratinib is an orally available tyrosine kinase inhibitor that irreversibly binds and inhibits EGFR, HER2 and HER4 receptor tyrosine kinases. cMET, the receptor for hepatocyte growth factor and target for cancer therapies, has been shown to be trans-phosphorylated by EGFR. In the current study, we evaluated HSP27 expression within a breast cancer cohort and its implications in cellular responsiveness to cMET inhibition and neratinib.

Methods: HSP27 transcript expression was analysed in our chemotherapy naïve breast cancer cohort (n=124) using quantitative PCR (qPCR) and compared to clinic-pathological information including long-term survival over a ten year follow up period. In addition, the correlation between HSP27 and HER2 expression was explored using Spearman Rank order. High-throughput cell migration analysis was performed using ECIS, on MCF-7 control and HSP27 siRNA knockdown cells in conjunction with neratinib and PHA 665752, a small molecule cMET inhibitor.

Results: In our primary breast cancer cohort, there were no significant associations between HSP27 transcript expression levels and tumour grade, TNM or estrogen receptor (ER) status. Combined survival expression analysis indicated that the worst patient prognosis was associated with high levels of both HER2 and HSP27 and high HER2 and low HSP27 whereas best patient prognosis was associated with low HER2 and low HSP27 expression. Knockdown of HSP27 in MCF7 cells brought about a reduction in cellular migration compared to the control. Additionally, this reduction was enhanced by the addition of neratinib, in a concentration dependent manner, and also cMET inhibition when individually treated. Furthermore, the greatest inhibitory effects on MCF-7 migration were seen following HSP27 knockdown and combined treatment with neratinib and PHA 665752.

Conclusions: Our current data suggests that HSP27 confers low sensitivity to drugs such as neratinib and PHA 665752, particularly in relation to cellular migration and hence potentially metastasis. Therefore, the targeting of HSP27, HER2 and cMET appear to act syngeristically to regulate cellular migration in vitro. Furthermore, clinically expression of HER2 and HSP27 may serve as a prognostic marker for breast cancer survival. Hence, combination therapies that target both HSP and HER2 pathways may provide new clinical opportunities for preventing breast cancer progression.

Citation Format: Owen S, Sanders AJ, Ruge F, Lalani AS, Avogadri-Connors F, Bryce RP, Jiang WG. Heat shock protein 27 (HSP27) and HER2 positively correlate in breast cancer and effect cell responsiveness to neratinib and cMET inhibitor [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-05-03.

Abstract P3-06-10: The impact of the Chinese medicine ShenLingLan on triple negative breast cancer, the metabolic and signalling pathways and clinical implications

Background. Triple negative breast cancer (TNBC) is a challenging both in the choice of therapies and clinical outcomes. In the present study, we investigated the potential prospect of a Chinese medicine formation, ShenLingLan, shown to have benefit to patients with cancer and able to influence the biological behaviour of cancer cells, on breast cancer cells in particular the differential response from TNBC and non-TNBC cells and, on the discovery that TNBC cells were particularly sensitive to the medicine, we went on to determine the signalling and mechanism of action.

Methods. A panel of three TNBC (MDA MB-231, BT20 and BT549) and a panel of three non-TNBC (MCF-7, ZR 75-1 and T47D) cells were used. A soluble extract from ShenLingLan, designated as SLDM, was utilised during this study. The proliferation, cellular migration and adhesiveness were tested using conventional and biophysical methods. Signalling profiling was conducted using a protein kinase array platform (Kinexustm). Metabolic profiling was conducted using the Seahorse platform. Expression of insulin receptor (IR) and insulin-like growth factor receptor (IGFR) gene transcripts (quantitative transcript analysis) and proteins (IHC) were conducted using a fresh breast cancer cohort and tissue array, respectively.

Results. SLDM had little effects on the growth of breast cancer cells. However, it had profound inhibitory effects on the migration of both TNBC and non-TNBC cells in a concentration dependent manner. Interestingly, TNBC cells were 5-20 times more sensitive than the non-TNBC cells in their migration and cell adhesion responses to SLDM. The protein array platform further revealed that, of the wide range of protein kinases, IR and IGRR1 were the most affected in that SLDM resulted in 25-50% reduction in the phosphorylation of IR and IR substrate in TNBC cells. SLDM also caused a contrasting response in IGFR1 phosphorylation in TNBC and non-TNBC cells. Metabolically, TNBC and non-TNBC cells responded to SLDM in very different fashions. For example, in TNBC cells SLDM resulted in a significant decrease in glycolytic activities, in particular that driven by insulin (30.2±12.2 pmol/min in control, 47.7±10 pmol/min with insulin and 35.4±4.2 pmol/min with insulin/SLDM, p=0.01). There is evidence that the mitochondria oxygen consumption (OCR) was also affected by SLDM in TNBC cells (p=0.01). These changes induced by SLDM were in clear contrast to non-TNBC cells which did not respond with significant reduction. Both TNBC and non-TNBC breast cancer tissues have higher IR staining than normal mammary tissues (p&lt;0.001). TNBC tumours also demonstrated significantly more positive IR staining than the non-TNBC tumours (p=0.04).

Conclusion. ShenLingLan has a profound inhibitory effect on the migration and cell-matrix adhesion of TNBC cells, with marked effect on the metabolics of these cells. This effect connects with reduction of the IR and IGFR activation, mainly through the reduction in glycolysis. Together with the clinical implication of IR and IGFR in breast cancer, ShenLingLan has an important role in the treatment of breast cancer with an emphasis in TNBCs.

Citation Format: Jiang WG, Owen S, Ruge F, Gao Y, Wang H, Wei C, Wu Y, Davies E. The impact of the Chinese medicine ShenLingLan on triple negative breast cancer, the metabolic and signalling pathways and clinical implications [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-06-10.

Abstract P3-15-04: Signalling pathways targeted by the YangZheng Xiaoji extract and the therapeutic implications in human breast cancer

Background. Yangzheng Xiaoji is a formulation of Chinese medicine and has been used in the treatment of solid cancer as an adjuvant to chemotherapy by reducing the side effects to the patient. There has been evidence to show that the medicine has a direct biological role in cancer cells. In the present study, we sought to investigate the potential effects of the medicine on breast cancer cells and in particular aimed to identify the key targets and molecular pathways contributing to the anti-cancer effect of the medicine.

Methods. Human breast cancer cell lines (BT549, BT20, MDA MB-231, MCF-7 and ZR 75-1) with varying invasiveness and receptor status were used. The soluble extract of Yangzheng Xiaoji, namely DME25 was used in the study. The effects of DME25 on the growth, toxicity and cellular migration were assessed. Signalling kinase changes were screened using kinase antibody array based array technologies. Kinases were also validated using phosphorylation based protein blotting.

Results. Of the five breast cancer cell lines tested, Yangzheng Xiaoji extract DME25 showed little cytotoxicity over a broad range of concentrations. However, DME25 were able to markedly reduce the migration of the panel of breast cancer tested, without being toxic. Triple negative cells responded in a similar fashion with other cells. It was also noted that the adhesion of these cells were also inhibited by DME25. Using a protein kinase array, it was shown that a number of kinase complexes were inhibited by the medicine, notable ones including EGFR family kinases (reduced by 35%), Janus protein kinases (JAK) (by 57%), and Ras-related C3 botulinum toxin substrate (Rac1 or CDC42 GTPase) (by 49%) and Ribosomal protein S6 kinases (RSKs) (by 52%). Given the clinical significance of RSKs in human breast cancer, we further evaluated the role of RSK and RSK inhibitors in DME mediated cell functions and have demonstrated that both in triple negative breast cancer cells and receptor positive breast cancer cell lines, DME25 was able to synergistically enhance the effect of RSK2 inhibitor, SL1010-1, on the both the cellular migration and cell growth.

Conclusion. Yangzheng Xiaoji has a broad and direct effect on the migration of breast cancer, an effect unrelated to hormone receptor status and independent of cytotoxicity. The medicine appears to target kinase pathway, particularly for the RSK kinases, suggesting an important clinical implication in the treatment of breast cancer.

Citation Format: Jiang WG, Ye L, Owen S, Ruge F, Martin TA, Sanders AJ, Gao G, Wei C, Wu Y, Davies E. Signalling pathways targeted by the YangZheng Xiaoji extract and the therapeutic implications in human breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-15-04.

Abstract P1-07-27: Prognostic value of programmed death 1/Programmed death ligand 1/ mammalian target of rapamycin/Rictor/Tuberin in human breast cancer

Background:The Mammalian Target of Rapamycin (mTOR) regulates a multitude of cellular processes including metabolism, proliferation and growth. It is known to form two multi-protein complexes - complex 1 (mTORC1) and complex 2 (mTORC2) with Raptor and Rictor being their core proteins vital for their integrity.

Tuberin, the product of the Tuberous Sclerosis Complex gene 2, TSC2, has been characterized as a tumour suppressor and negatively regulates the mTOR pathway.

Programmed Death 1 (PD-1), a transmembrane protein particularly expressed on the surface of tumour cells, acts as an immune checkpoint receptor. Together with its ligand Programmed Death Ligand 1 (PDL-1) they form a pathway which when activated influences anti-tumour immunity and supresses anti-tumour adaptive responses. The expression of PD1/PDL-1 is lightly regulated by the mTOR pathway.

We investigated the value of expression patterns of all these molecules in breast cancer as potential prognostic factors.

Materials and Methods: Quantitative PCR (qPCR) analysis was used to determine the transcript expression profile of the five genes of interest (PD-1, PDL-1, mTOR, Rictor and Tuberin) in 128 breast cancer specimens.The correlation between PD-1 or PDL-1 with mTOR, Rictor and Tuberin was assessed using the Spearman Rank Order Correlation. Subsequently, a combined analysis was performed, where the influence of favourable expression in relation to patient overall (OS) and disease free survival (DFS) using the Kaplan Meier survival curves and multivariate analysis.

Results: The mRNA expression of the molecules showed a varying degree of association with the clinicopathological parameters. PD-1 transcript expression showed a significant correlation with mTOR expression (p &lt; 0.001). PDL-1 transcript expression was seen to correlate with mTOR (p &lt; 0.001), Rictor (p &lt; 0.001) and Tuberin (p &lt; 0.01) transcript expression. However, when the expression profile was analysed using an integrated expression score, the combined predictive value for the clinical outcome of the five genes was highly significant in terms of OS (p &lt; 0.001) and DFS (p = 0.001), and was found to be an independent prognostic factor (p&lt;0.001) for breast cancer related death using a multivariate analysis.

Conclusions: Our study identifies a molecular signature of 5 genes as a powerful prognostic predictor of OS and DFS in patients with breast cancer.

Citation Format: Uhercik M, Sanders AJ, Owen S, Davies EL, Sharma AK, Jiang WG, Mokbel K. Prognostic value of programmed death 1/Programmed death ligand 1/ mammalian target of rapamycin/Rictor/Tuberin in human breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-07-27.

Progression pattern and adverse events with bevacizumab in glioblastoma

BACKGROUND

The use of bevacizumab in the management of glioblastoma multiforme (gbm) remains controversial. In Canada, bevacizumab is approved for the treatment of recurrent gbm. We describe a pattern of progression across treatment lines in gbm.

METHODS

During 2008-2014, 64 patients diagnosed with gbm were treated with bevacizumab at McGill University hospitals. Of those patients, 30 (46.9%) received bevacizumab in the first line (B1L), and 34 (53.1%) received it in the second line and beyond (B2L+). The average length of treatment with bevacizumab was 24.4 weeks (range: 0-232.7 weeks). The patterns of progression were categorized as local, distant, diffuse, multifocal, or multi-pattern.

RESULTS

Local progression was seen in 46.7% of B1L patients and 26.5% of B2L+ patients, distant in 3.3% and 2.9%, diffuse in 20% and 47%, multifocal in 10% and 8.8%, and multi-pattern in 3.3% and 11.8%. No differences between the groups were observed for the distant (p = 0.3) or diffuse (p = 0.4) patterns. Grades 3 and 4 adverse events in the B1L and B2L+ groups were fatigue (33.3% vs. 17.6% respectively), hypertension (26.7% vs. 5.9%), thrombocytopenia (26.7% vs. 11.8%), neutropenia (26.7% vs. 11.8%), anemia (23.3% vs. 11.8%), leucopenia (20% vs. 8.8%), deep vein thrombosis (23.3% vs. 5.9%), seizure (16.7% vs. 8.8%), brain hemorrhage (6.7% vs. <1%), and delayed wound healing (6.7% vs. 2.9%). More total grades 3 and 4 adverse events occurred in the B1L group (p = 0.000519).

CONCLUSIONS

In our cohort, patterns of progression were not different in B1L and B2L+ patients. Moreover, both groups experienced similar adverse events, although more grades 3 and 4 events occurred in the B1L group, implying that severe adverse events in B1L patients could negatively affect survival outcomes.

The clinical significance and impact of interleukin 15 on keratinocyte cell growth and migration

Chronic wounds represent a significant burden to health services and are associated with patient morbidity. Novel methods to diagnose and/or treat problematic wounds are needed. Interleukin (IL)-15 is a cytokine involved in a number of biological processes and disease states such as inflammation, healing and cancer progression. The current study explores the expression profile of IL-15 and IL-15 receptor α (IL-15Rα) in chronic wounds and its impact on keratinocytes. IL-15 and IL-15Rα expression were examined in healing and non-healing chronic wounds using qPCR and immunohistochemical analysis. The impact of recombinant IL-15 (rhIL-15) on human adult low calcium temperature (HaCaT) keratinocyte growth and migratory potential was further examined. IL-15 transcript expression was slightly, though non-significantly elevated in healing chronic wounds compared with non-healing chronic wounds. IL-15 protein staining was minimal in both subtypes of chronic wounds. By contrast, IL-15Rα transcript and protein expression were both observed to be enhanced in non-healing chronic wounds compared with healing chronic wounds. The treatment of HaCaT cells with rhIL-15 generally enhanced cell growth and promoted migration. Analysis with small molecule inhibitors suggested that the pro-migratory effect of rhIL-15 may be associated with ERK, AKT, PLCγ and FAK signalling. IL-15 may promote healing traits in keratinocytes and the differential expression of IL-15Rα is observed in chronic wounds. Together, this may imply a complex role for this interleukin in wound healing.

Comparing the Performance Status Scale and MD Anderson Dysphagia Inventory as swallowing outcome measures in head and neck cancer: a prospective cohort study

OBJECTIVES

To examine the relationship between the two disease-specific measures currently in use to assess swallowing outcomes following treatment in patients with head and neck cancer: the Performance Status Scale (PSS) and MD Anderson Dysphagia Inventory (MDADI).

DESIGN

A prospective cohort study.

SETTING

Four head and neck cancer multidisciplinary clinics in the North of England Cancer Network.

PARTICIPANTS

114 patients with cancers of the upper aerodigestive tract.

MAIN OUTCOME MEASURE

Measures of swallowing function administered prospectively across 4 timepoints

RESULTS

Spearman's correlation coefficients were used to measure the relationship between the two scales. There was statistically significant correlation between the two tools at pre-treatment (rs = 0.428, P < 0.000), 3 months post-treatment (rs = 0.454, P < 0.002), 6 months post-treatment (rs = 0.551, P < 0.000) and 12 months post-treatment (rs = 0.680, P < 0.000).

CONCLUSION

This is the first prospective study comparing the MDADI and PSS questionnaires at multiple time points. Our study shows that these different instruments have a good relationship in measuring swallowing function in patients with head and neck cancer in short and medium term after treatment.

Do-not-attempt-cardiopulmonary-resuscitation decisions: an evidence synthesis

Background

Cardiac arrest is the final common step in the dying process. In the right context, resuscitation can reverse the dying process, yet success rates are low. However, cardiopulmonary resuscitation (CPR) is a highly invasive medical treatment, which, if applied in the wrong setting, can deprive the patient of dignified death. Do-not-attempt-cardiopulmonary-resuscitation (DNACPR) decisions provide a mechanism to withhold CPR. Recent scientific and lay press reports suggest that the implementation of DNACPR decisions in NHS practice is problematic.

Aims and objectives

This project sought to identify reasons why conflict and complaints arise, identify inconsistencies in NHS trusts’ implementation of national guidelines, understand health professionals’ experience in relation to DNACPR, its process and ethical challenges, and explore the literature for evidence to improve DNACPR policy and practice.

Methods

A systematic review synthesised evidence of processes, barriers and facilitators related to DNACPR decision-making and implementation. Reports from NHS trusts, the National Reporting and Learning System, the Parliamentary and Health Service Ombudsman, the Office of the Chief Coroner, trust resuscitation policies and telephone calls to a patient information line were reviewed. Multiple focus groups explored service-provider perspectives on DNACPR decisions. A stakeholder group discussed the research findings and identified priorities for future research.

Results

The literature review found evidence that structured discussions at admission to hospital or following deterioration improved patient involvement and decision-making. Linking DNACPR to overall treatment plans improved clarity about goals of care, aided communication and reduced harms. Standardised documentation improved the frequency and quality of recording decisions. Approximately 1500 DNACPR incidents are reported annually. One-third of these report harms, including some instances of death. Problems with communication and variation in trusts’ implementation of national guidelines were common. Members of the public were concerned that their wishes with regard to resuscitation would not be respected. Clinicians felt that DNACPR decisions should be considered within the overall care of individual patients. Some clinicians avoid raising discussions about CPR for fear of conflict or complaint. A key theme across all focus groups, and reinforced by the literature review, was the negative impact on overall patient care of having a DNACPR decision and the conflation of ‘do not resuscitate’ with ‘do not provide active treatment’.

Limitations

The variable quality of some data sources allows potential overstatement or understatement of findings. However, data source triangulation identified common issues.

Conclusion

There is evidence of variation and suboptimal practice in relation to DNACPR decisions across health-care settings. There were deficiencies in considering, discussing and implementing the decision, as well as unintended consequences of DNACPR decisions being made on other aspects of patient care.

Future work

Recommendations supported by the stakeholder group are standardising NHS policies and forms, ensuring cross-boundary recognition of DNACPR decisions, integrating decisions with overall treatment plans and developing tools and training strategies to support clinician and patient decision-making, including improving communication.

Study registration

This study is registered as PROSPERO CRD42012002669.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Recognition of subtle and universal facial expressions in a community-based sample of adults classified with intellectual disability

BACKGROUND

Across the USA and UK, schemes now exist to aid the successful integration of adults with mild to moderate intellectual disabilities into general society. One factor that may prove important to the success of such schemes is social competence. Here, understanding the facial expressions of others is critical, as emotion recognition is a prerequisite to empathetic responding and an essential factor in social functioning. Yet research in this area is lacking, especially in community-based samples.

METHOD

We investigated the performance of 13 adults with mild to moderate intellectual disability (ID), relative to 13 age-matched controls, on three tasks of emotion recognition (emotion categorisation; recognition of valence; and recognition of arousal), using a number of 'basic' (angry and happy) and more 'subtle' (compassionate and critical) emotional expressions, as well as the posers face in a default relaxed (i.e. 'neutral') state. Importantly, the sample was drawn from a community-based initiative and was therefore representative of populations' government schemes target.

RESULTS

Across emotion recognition tasks, the ID adults, as compared with controls, were significantly impaired when labelling the emotions displayed by the poser as well as recognising the associated 'feelings' conveyed by these faces. This was especially true for the neutral, compassionate and angry facial expressions. For example, ID adults demonstrated deficits in categorising neutral and subtle emotional expressions, as well as assessing the valence of such facial expressions. In addition, ID adults also struggled to assess arousal levels; especially those associated with compassionate and angry faces.

CONCLUSION

Given both basic and subtle emotions are conveyed in a range of daily situations, errors in interpreting such facial expressions and, relatedly, understanding what potential behaviours such expressions signify could contribute to the social difficulties ID adults face. This is important because current initiatives such as 'personalisation' do not appear to have schemes supporting training in this area, and understanding the facial expressions of others is, after all, one of our most important non-verbal social communication tools.