Immune cell dynamics deconvoluted by single-cell RNA sequencing in normothermic machine perfusion of the liver

Normothermic machine perfusion (NMP) has emerged as an innovative organ preservation technique. Developing an understanding for the donor organ immune cell composition and its dynamic changes during NMP is essential. We aimed for a comprehensive characterization of immune cell (sub)populations, cell trafficking and cytokine release during liver NMP. Single-cell transcriptome profiling of human donor livers prior to, during NMP and after transplantation shows an abundance of CXC chemokine receptor 1⁺/2⁺ (CXCR1⁺/CXCR2⁺) neutrophils, which significantly decreased during NMP. This is paralleled by a large efflux of passenger leukocytes with neutrophil predominance in the perfusate. During NMP, neutrophils shift from a pro-inflammatory state towards an aged/chronically activated/exhausted phenotype, while anti-inflammatory/tolerogenic monocytes/macrophages are increased. We herein describe the dynamics of the immune cell repertoire, phenotypic immune cell shifts and a dominance of neutrophils during liver NMP, which potentially contribute to the inflammatory response. Our findings may serve as resource to initiate future immune-interventional studies.

Abstract PR008: Development and testing of a polygenic risk score for breast cancer. Aggressiveness

Background: Aggressive breast cancers have increased proliferation or metastatic potential and portend a poor prognosis. The ability to identify women at elevated risk of aggressive cancers could have major implications for screening and prevention, yet there are no available tools for predicting aggressive cancer risk. We sought to construct a polygenic risk score (PRS) for aggressive breast cancers by leveraging the associations of single nucleotide polymorphisms (SNPs) with tumor gene expression. We used as our measure of aggressiveness the risk of recurrence score weighted on proliferation (ROR-P), a validated tumor prognostic signature. We hypothesized that known breast cancer susceptibility SNPs would have differential associations with ROR-P, which could then be used to construct a PRS for ROR-P. Methods: We developed our PRS in a case-only analysis of 3 studies containing SNP genotypes and tumor gene expression: The Cancer Genome Atlas, METABRIC, and the I-SPY 2 TRIAL (total n=2,363). We used linear regression models to evaluate individual SNP associations with ROR-P, adjusted for genetic ancestry and study. We then constructed PRS using varying p-value thresholds and used cross-validation to identify the PRS with highest model r2. To assess whether the ROR-P PRS was associated with poor prognosis, we performed survival analysis in two longitudinal cohorts of breast cancer patients: the UK Biobank (women with incident invasive cancers only) and the Pathways Study. These studies included 10,196 total cases with 785 deaths. We built Cox proportional hazards models to evaluate the association between the ROR-P PRS (adjusted for genetic ancestry) and breast cancer-specific survival (BCSS) in both studies. We then performed meta-analysis of the Cox model results. We also constructed joint models containing the ROR-P PRS and a PRS representing the case-case risk of ER-negative vs. ER-positive cancer, PRSER-/ER+. Results: We tested the associations between 226 breast cancer susceptibility SNPs and ROR-P. The best-performing PRS contained 76 SNPs and had a cross-validated r2 of 0.051. In the UK Biobank and Pathways Study, higher ROR-P PRS was associated with worse BCSS, with nearly identical effects observed in each study, HR per standard deviation of 1.13 (95% CI 1.05-1.21, p=9.0x10-4) in meta-analysis. The ROR-P PRS’s effect was minimally attenuated when adjusted for PRSER-/ER+, suggesting that the ROR-P PRS was providing additional prognostic information beyond ER status. Conclusions: We used breast cancer susceptibility SNPs to construct a PRS for ROR-P, a prognostic signature recapitulating aggressiveness, and found the ROR-P PRS to be associated with worse BCSS. Our findings represent an improvement on current PRS for overall breast cancer risk, which preferentially predict cancers with favorable prognosis. Given that aggressive cancers are more likely to present as advanced cancers even among women undergoing routine screening, our findings could potentially identify women who may benefit from more intensive screening.

Citation Format: Yiwey Shieh, Jacquelyn Roger, Christina Yau, Denise Wolf, Gillian Hirst, Lamorna Swigart, Scott Huntsman, Donglei Hu, Jovia Nierenberg, Pooja Middha, Rachel Heise, Linda Kachuri, Qianqian Zhu, Song Yao, Christine Ambrosone, Marilyn Kwan, Bette Caan, John Witte, Lawrence Kushi, Laura van ’T. Veer, Laura Esserman, Elad Ziv. Development and testing of a polygenic risk score for breast cancer. Aggressiveness. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr PR008.

Safety and efficacy of HSP90 inhibitor ganetespib for neoadjuvant treatment of stage II/III breast cancer

HSP90 inhibitors destabilize oncoproteins associated with cell cycle, angiogenesis, RAS-MAPK activity, histone modification, kinases and growth factors. We evaluated the HSP90-inhibitor ganetespib in combination with standard chemotherapy in patients with high-risk early-stage breast cancer. I-SPY2 is a multicenter, phase II adaptively randomized neoadjuvant (NAC) clinical trial enrolling patients with stage II-III breast cancer with tumors 2.5 cm or larger on the basis of hormone receptors (HR), HER2 and Mammaprint status. Multiple novel investigational agents plus standard chemotherapy are evaluated in parallel for the primary endpoint of pathologic complete response (pCR). Patients with HER2-negative breast cancer were eligible for randomization to ganetespib from October 2014 to October 2015. Of 233 women included in the final analysis, 140 were randomized to the standard NAC control; 93 were randomized to receive 150 mg/m2 ganetespib every 3 weeks with weekly paclitaxel over 12 weeks, followed by AC. Arms were balanced for hormone receptor status (51-52% HR-positive). Ganetespib did not graduate in any of the biomarker signatures studied before reaching maximum enrollment. Final estimated pCR rates were 26% vs. 18% HER2-negative, 38% vs. 22% HR-negative/HER2-negative, and 15% vs. 14% HR-positive/HER2-negative for ganetespib vs control, respectively. The predicted probability of success in phase 3 testing was 47% HER2-negative, 72% HR-negative/HER2-negative, and 19% HR-positive/HER2-negative. Ganetespib added to standard therapy is unlikely to yield substantially higher pCR rates in HER2-negative breast cancer compared to standard NAC, and neither HSP90 pathway nor replicative stress expression markers predicted response. HSP90 inhibitors remain of limited clinical interest in breast cancer, potentially in other clinical settings such as HER2-positive disease or in combination with anti-PD1 neoadjuvant chemotherapy in triple negative breast cancer.Trial registration: www.clinicaltrials.gov/ct2/show/NCT01042379.

The liver-resident immune cell repertoire - A boon or a bane during machine perfusion?

The liver has been proposed as an important “immune organ” of the body, as it is critically involved in a variety of specific and unique immune tasks. It contains a huge resident immune cell repertoire, which determines the balance between tolerance and inflammation in the hepatic microenvironment. Liver-resident immune cells, populating the sinusoids and the space of Disse, include professional antigen-presenting cells, myeloid cells, as well as innate and adaptive lymphoid cell populations. Machine perfusion (MP) has emerged as an innovative technology to preserve organs ex vivo while testing for organ quality and function prior to transplantation. As for the liver, hypothermic and normothermic MP techniques have successfully been implemented in clinically routine, especially for the use of marginal donor livers. Although there is evidence that ischemia reperfusion injury-associated inflammation is reduced in machine-perfused livers, little is known whether MP impacts the quantity, activation state and function of the hepatic immune-cell repertoire, and how this affects the inflammatory milieu during MP. At this point, it remains even speculative if liver-resident immune cells primarily exert a pro-inflammatory and hence destructive effect on machine-perfused organs, or in part may be essential to induce liver regeneration and counteract liver damage. This review discusses the role of hepatic immune cell subtypes during inflammatory conditions and ischemia reperfusion injury in the context of liver transplantation. We further highlight the possible impact of MP on the modification of the immune cell repertoire and its potential for future applications and immune modulation of the liver.

NLRP3 mediates atheromatous plaque macrophage proliferation

Background

Macrophage accumulation in atherosclerotic plaques drives disease progression largely dependent on in situ proliferation. We previously reported that systemic cholesterol lowering or reduced modified lipoprotein uptake supress atheromatous plaque macrophage proliferation. In this work we investigate the intracellular mediators of macrophage proliferation.

Methods and results

Macrophages deficient in scavenger receptors CD36 or Msr1 and impaired in cholesterol-rich lipoprotein uptake, proliferated less compared to control macrophages in the same plaque exposed to the same lipid levels in a LDLR-deficient bone marrow irradiation mixed chimera model. Proliferation of plaque macrophages deficient in the intracellular cholesterol sensor LXR was not impaired, however. As modified LDL uptake can activate the NLRP3 inflammasome, we generated mixed bone marrow knockout chimeras for components of the inflammasome. NLRP3 but not Caspase-1 or interleukin-1 receptor deficient macrophages proliferated 35% less compared to NLRP3-expressing macrophages in the same plaque in vivo. These results were confirmed in NLRP3-deficient oxLDL stimulated macrophages in vitro. In line, NLRP3 inhibition of human carotid artery plaque cultures suppressed human plaque macrophage proliferation and reduced inflammasome-dependent IL-1b secretion. However, IL-1b supplementation did not restore local macrophage proliferation in accord with our findings in IL-1 receptor deficient murine plaque macrophages.

Conclusion

We identified a novel role for NLRP3, independent of the canonical Caspase-1–IL-1b inflammasome pathway, in mediating macrophage proliferation in atherosclerotic plaques in mice and men representing a druggable target.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): DFG

The role of P2Y12 in cardiovascular disease beyond atherothrombosis: P2Y12 signaling promotes emergency hematopoiesis after myocardial infarction

Background

Adenosine diphosphate (ADP) plays a pivotal role in platelet activation. The purinergic ADP-receptor P2Y12 has therefore been targeted in the treatment of cardiovascular disease (CVD) to prevent atherothrombosis (1). Beyond P2Y12 expression on platelets, purinergic receptors have also been described on hematopoietic stem and progenitor cells (LSK) (2). After myocardial infarction (MI), accelerated LSK proliferation launches emergency hematopoiesis as the driving force behind the inflammatory response to MI, increasing inflammatory cell production in the bone marrow (BM) and providing leukocyte resupply for local cell recruitment to the infarct (3). The inflammatory cascade after MI covers intricate multilayered interactions between the injured myocardium and the hematopoietic BM that still remain to be fully elucidated and may unearth novel therapeutic strategies. Whereas P2X receptors have recently been found to be involved in cell trafficking (4), the role of P2Y receptors in the hematopoietic BM have not yet been characterized.

Purpose

This study aims to characterize the influence of P2Y12 signaling on emergency hematopoiesis and cardiac remodeling after MI.

Methods

Permanent coronary ligation was performed for MI to assess BM activation, inflammatory cell composition, cardiac remodeling and function in murine global and platelet-specific P2Y12 knockout models and under pharmacological P2Y12 inhibition with prasugrel using flow cytometry, qPCR, immunohistochemistry and echocardiography. In vitro studies including colony forming unit (CFU) assays and flow cytometry allowed for investigation of ADP-dependent effects on LSK cells and intracellular pathway analysis.

Results

We identified ADP as a danger signal for the hematopoietic BM, fueling emergency hematopoiesis by promoting Akt phosphorylation and cell cycle progression. Detection of P2Y12 expression in LSK implicated a direct effect of ADP on LSK via P2Y12 signaling. P2Y12 deficiency and P2Y12 inhibition with prasugrel decelerated emergency hematopoiesis and consecutively reduced the excessive inflammatory response to MI, translating to lower numbers of hematopoietic progenitors and inflammatory cells in the blood and infarct. Ultimately, P2Y12 inhibition ameliorated chronic adverse cardiac remodeling and preserved cardiac function after MI.

Conclusion

ADP-dependent P2Y12-mediated activation of hematopoietic stem and progenitor cells in the BM promotes emergency hematopoiesis after MI and fuels post-ischemic inflammation, proposing a novel role of P2Y12 antagonists in CVD beyond atherothrombosis.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft (DFG)

Abstract P2-02-02: Differences in levels of circulating tumor cells (CTC) and disseminated tumor cells (DTC) in early-stage lobular versus ductal breast cancer

Background: Invasive lobular carcinoma (ILC) is the second most common type of breast cancer after invasive ductal carcinoma (IDC). ILC has unique features, such as a diffuse growth pattern due to characteristic loss of E cadherin, and a different pattern of disease metastasis compared to IDC. Prior investigators have shown increased numbers of circulating tumor cells (CTCs) in patients with metastatic ILC versus IDC. We explored the distribution of CTCs and disseminated tumor cells (DTCs) in early stage ILC versus IDC. Methods: We performed a secondary data analysis of the TIPPING study, an institutional review board approved study that pre-operatively collected blood and bone marrow samples from 655 treatment-naïve early-stage breast cancer patients. We analyzed data from 284 patients who had CTCs and DTC enumerated by an EPCAM-based method involving immunomagnetic enrichment and flow cytometry (IE/FC) (61 patients with ILC and 223 patients with IDC). We compared CTC and DTC counts by histology using the Welch Two Sample t-test, linear regression models, as well as ANOVA tests. Multivariate Cox regression analyses were performed to assess association between levels of CTCs/DTCs and clinical outcomes (distant recurrence-free survival [DRFS] and breast cancer-specific survival [BCSS]). Results: ILC tumors were lower grade than IDCs and had a higher proportion of HR+HER2- subtypes (92.00% vs. 75.30%; p<0.001). ILC patients had significantly higher CTC counts than IDC patients (mean 2.11 vs. 0.71 CTCs/mL; p<0.001), a difference that retained significance after adjusting for clinical variables (p=0.003). Additionally, we identified a subset of ILC patients (n = 9; 14.75%) that have elevated CTCs, which was absent in the IDC subset. ILC patients with elevated CTC levels showed no statistically significant association between CTC as a continuous variable with nodal status and breast cancer stage (p=0.26, p=0.25, respectively). In our study, the overall median follow-up was 7.26 years for DRFS and 8.9 years for BCSS. In the subset of ILC patients with elevated CTCs, CTC level as a continuous variable did not show significant association with DRFS or BCSS in a multivariate model adjusting for clinical variables. In the IDC subset, CTC level as a continuous variable did not show significant association with DRFS or BCSS in a multivariate model adjusting for clinical variables.Furthermore, there was no difference in the number of DTCs in ILC versus IDC. DTC level as a continuous variable did not show significant association with DRFS or BCSS in a multivariate model adjusting for clinical variables in both ILC and IDC subsets. Conclusions: Early-stage ILC patients have significantly higher CTC levels than those observed in IDC patients, and we hypothesize that the reason may be due to lower cell-cell adhesion. ILC spans the spectrum of indolent (benign) to high risk (bad actor) disease. Thus, biomarkers like CTCs may allow us to identify ILC patients who are at higher risk of late recurrence and make appropriate therapeutic decisions at earlier point in time. Studies like Endocrine Optimization Pilot in I-SPY 2 are ongoing to further investigate the use of biomarkers like CTCs to inform outcomes. Due to the short follow-up period, we will conduct an additional follow-up which should give us 10 years of follow-up, which is likely needed due to the risk for late recurrence in ILC patients.

Citation Format: Silver Alkhafaji, Denise Wolf, Mark Magbanua, Laura Van 't Veer, John Park, Laura J. Esserman, Rita A. Mukhtar. Differences in levels of circulating tumor cells (CTC) and disseminated tumor cells (DTC) in early-stage lobular versus ductal breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-02-02.

Abstract PD9-04: Tumor-released circulating orphan non-coding RNAs reflect treatment response and survival in breast cancer

Background: Liquid biopsies have emerged as effective diagnostic tools in disease monitoring and minimal residual disease detection. Circulating tumor DNA (ctDNA) was recently shown to be a predictor of poor response and recurrence in breast cancer. However, ctDNA shedding from breast tumors can rapidly decrease during treatment, resulting in reduced sensitivity in measuring early changes in tumor response or residual cancer burden (RCB) after neoadjuvant chemotherapy (NAC). We recently reported the discovery of orphan non-coding RNAs (oncRNAs), a class of small RNAs that are not present in healthy cells, but emerge from cancer cells. Similar to ctDNA, tumor-released oncRNAs can be used to detect the presence of an underlying tumor; however, since they are actively released by cancer cells, their abundance in the cell-free compartment is substantially higher than ctDNA. Therefore, we hypothesized that monitoring circulating oncRNAs in blood permits a more sensitive approach to measuring treatment response (i.e., pathologic complete response, or pCR) and estimating RCB. Patients and Methods: Cell-free RNA (cfRNA) was extracted from ~1 ml sera of 72 breast cancer patients treated in the neoadjuvant I-SPY 2 TRIAL with NAC alone or combined with MK-2206 (AKT inhibitor) treatment. For each patient, treatment-naïve samples (T0) were compared with samples from post-treatment and prior to surgery (T3) time-point. RNA samples were subjected to small RNA sequencing (SMARTer), and the presence and abundance of cell-free oncRNA species were then determined by identifying and counting the reads that map to oncRNA loci across samples. Notably, oncRNAs species were pre-annotated from the Cancer Genome Atlas (TCGA), and our approach does not require bespoke personalized assays. We used a machine-learning model to compare abundance of cfRNA species before and after treatment (i.e., T3-T0) to predict pCR and RCB. For this, we split our cohort into a training and a testing set (48 and 24) and trained a model to simultaneously learn the presence of residual disease (pCR vs. no pCR) and its extent (RCB). We then measured the performance of our model on the held-out test data and the entire dataset. To confirm the robustness of our model, we also employed a leave-one-out strategy, whereby pCR and RCBIndex of each patient was predicted using a model that was trained on the other patients in the cohort. Finally, to assess the ability of our oncRNA-based model to risk-stratify patients who fail to achieve pCR (without having been explicitly trained on relapse data), we used the model’s oncRNA score to predict patients at the highest risk of distant recurrence (n=8 out of 36) and performed a multivariate Cox analysis, controlling for HR/Her2 status (median follow-up time was 4.8 years). Results: The model’s accuracy for predicting pCR—based on changes in circulating oncRNA species between T3 and T0—was 85% for the training data and 79% for the held-out test data (positive predictive value of 75% and negative predictive value of 83%) with combined accuracy of 83%; precision 86% and recall 83%; Pearson R=0.5 for RCB. A leave-one-out strategy showed similar performance (area under ROC of 0.77 versus 0.81 in train-test split). Finally, among the patients who failed to achieve pCR, we observed a significantly higher risk of distant recurrence in those with the highest scores (DRFS: hazard-ratio = 8.4, ANOVA P<0.05). Conclusion: In this study, we have shown that the changes in tumor-released oncRNA content of the blood are a significant predictor of clinical outcomes. Our results demonstrate that oncRNA fingerprints are blood-accessible, and allow us to build predictive models of tumor response. We are currently expanding this study to additional cohorts, and we expect to report the results for a longitudinal analysis that includes ~200 patients from I-SPY2.

Citation Format: Hani Goodarzi, Albertas Navickas, Jefferey Wang, Kristle Garcia, Mark J Magbanua, Lisa Fish, Lamorna Brown Swigart, Gillian Hirst, Denise Wolf, Christina Yau, Jo Chien, Carol Simmons, Amy Delson, Laura Esserman, Laura van 't Veer. Tumor-released circulating orphan non-coding RNAs reflect treatment response and survival in breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD9-04.

Abstract PD8-07: Evaluation of Tucatinib + (Paclitaxel + Pertuzumab + Trastuzumab) followed by AC in high-risk HER2 positive (HER2+) stage II/III breast cancer: Results from the I-SPY 2 TRIAL

Background: I-SPY 2 is a multicenter, phase 2 trial using response-adaptive randomization within molecular subtypes defined by receptor status and MammaPrint (MP) risk to evaluate novel agents as neoadjuvant therapy for women with high-risk breast cancer. Tucatinib is a potent HER2 (ErbB2) tyrosine kinase inhibitor, selective for HER2 vs. epidermal growth factor receptor (EGFR) and is active vs. brain metastases. Safety and efficacy of tucatinib combined with paclitaxel, pertuzumab, and trastuzumab are unknown and were tested in a planned 10 patient (pt) safety run-in of the I-SPY 2 trial. Methods: Women with tumors ≥ 2.5cm were eligible for screening. Only pts with tumors that were HER2+ by FISH were eligible for this treatment. Treatment included tucatinib (max dose 300 mg) BID for 12 weeks with weekly paclitaxel 80 mg/m2 and trastuzumab (2 mg/kg weekly following loading), and pertuzumab (420 mg every 3 weeks following loading), followed by doxorubicin/cyclophosphamide (AC) every 2 weeks x 4. The control arm was weekly paclitaxel and trastuzumab with pertuzumab for 12 weeks followed by AC every 2 weeks x 4. All pts undergo serial MR imaging and response at 3 & 12 weeks is combined with real time pCR data to estimate, and continuously update, the predicted pCR rate for each trial arm. The goal of the trial is to identify/graduate regimens with ≥85.% Bayesian predictive probability of success (i.e. demonstrating superiority to control) in a future 300-patient phase 3 neoadjuvant trial with a pCR endpoint. This run-in arm was conducted to determine safety of combining tucatinib with paclitaxel/trastuzumab/pertuzumab, monitoring special adverse events of interest including LFT elevations and gastrointestinal toxicities.Methods: The I-SPY 2 methods have been previously published. Results: 20 pts were evaluable in tucatinib treatment arm. The control arm included 329 historical controls enrolled since April 2010. The initial tucatinib dose was 300 mg BID. After enrollment of the first 8 pts, there were 3 pts with grade 3 LFT elevations, 2 pts with grade 2/3 diarrhea, 1 pt with grade 2 neutropenia, and 1 pt with grade 3 nausea. After this safety review, the tucatinib dose was lowered to 250 mg BID. Among 5 additional pts enrolled, 3 developed grade 2/3 LFT abnormalities. The protocol was then modified to tucatinib 150 mg BID days 1-28 and then 250 mg BID days 29-84; 7 pts were treated. Safety data were reviewed after 20 pts were enrolled; the arm was then suspended due to similar LFT elevations regardless of tucatinib dose reduction or schedule. 7 of 20 pts (35%) had reversible Grade 3 or higher ALT/AST elevation (Table). No pt met criteria for Hy’s Law. In terms of efficacy, 12 of 14 evaluable pts had > 80% reduction of tumor volume by 12 weeks, measured by MRI assessment of functional tumor volume (FTV). Conclusion: The goal of the run-in arm was to determine the safety of adding tucatinib to the combination of paclitaxel/trastuzumab/pertuzumab. The addition of tucatinib resulted in unacceptable but reversible LFT elevations despite tucatinib dose reduction. Tucatinib containing therapy resulted in >80% decline in tumor volume at 12 weeks in 86% of pts. Tucatinib showed a high level of activity when combined with paclitaxel/trastuzumab/pertuzumab, but the combination is not feasible. Table: Number of pts with grade 2, 3, and 4 LFT elevations by treatment schedule (highest grade per patient per event, ALT or

Treatment scheduleGrade 2 LFT elevationGrade 3 LFT elevationGrade 4 LFT elevationTucatinib 300 mg BID030Tucatinib 250 mg BID210Tucatinib 150 mg BID days 1-28 followed by 250 mg BID days 29 to 84112

Citation Format: David A Potter, Erin Roesch, Christina Yau, Ruixiao Lu, Denise Wolf, Susan Samson, Debra Stafford, Kathy S Albain, Claudine Isaacs, Meghana Trivedi, Douglas Yee, Judy Boughey, Alexandra Thomas, A. Jo Chien, Nola Hylton, Wen Li, Angela DeMichele, Jane Perlmutter, W. Fraser Symmans, Dawn L Hershman, Michelle Melisko, Laura J van 't Veer, Amy Wilson, Smita M Asare, Donald A Berry, Richard Schwab, Hope S Rugo, Laura J Esserman. Evaluation of Tucatinib + (Paclitaxel + Pertuzumab + Trastuzumab) followed by AC in high-risk HER2 positive (HER2+) stage II/III breast cancer: Results from the I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD8-07.

Abstract PD10-07: Chemokine12 (CK12) tertiary lymphoid gene expression signature as a predictor of response in 3 immunotherapy arms of the neoadjuvant ISPY 2 TRIAL - pembrolizumab with and without SD101, and durvalumab combined with olaparib - and in 9 other arms of the trial including platinum-based and dual-anti-HER2 therapies

Background: The CK12 expression signature consists of genes CCL2, CCL3, CCL4, CCL5, CCL8, CCL18, CCL19, CCL21, CXCL9, CXCL10, CXCL11, CXCL13 and was previously shown to associate with the presence of T and B cell rich tertiary lymphoid structures in melanoma and other cancers, and with better patient survival independent of tumor staging and treatment. I-SPY 2 is a biomarker-rich, phase II neoadjuvant platform trial for high risk early stage breast cancer. Here we leverage the I-SPY 2 biomarker program to test the hypothesis that this signature associates with sensitivity to neoadjuvant immunotherapies and potentially other classes cancer therapeutics in breast cancer. Methods: Data from 1130 patients across 12 arms of I-SPY2 (control (ctr): 210; veliparib/carboplatin (VC): 71; neratinib (N): 114; MK2206: 93; ganitumab: 106; ganetespib: 93; AMG386: 134; TDM1/pertuzumab(P): 52; H/P: 44; pembrolizumab (pembro): 69; durvalumab/olaparib (durva/olap): 71; pembro/SD101: 72) were available for analysis. Pre-treatment FF (n=987) or FFPE (n=143) biopsies were assayed using Agilent gene expression arrays. Signature scores were calculated as the average expression level across the 12 genes, after z-score normalization. We used logistic modeling to assess association with pCR in each arm in a model adjusting for HR and HER2 (likelihood ratio test, p<0.05). This analysis was also performed within HR/HER2 receptor subsets, numbers permitting. We also assessed differences in levels across HR/HER2 subsets using ANOVA and Tukey post-hoc testing. Our statistics are descriptive rather than inferential and do not adjust for multiplicities of other biomarkers outside this study. Results: CK12 levels associate with HR/HER2 status (ANOVA p=1.07E-14), with higher levels in TN and HR-HER2+ subsets and lower levels in HR+ groups. Overall, patients with higher levels of CK12 were significantly more likely to achieve pCR in all 3 IO arms: pembro (OR=3.4/1SD), pembro/SD101 (OR=4/1SD), and durva/olaparib (OR=2.5/1SD) (LR p<0.05), in a model adjusting for HR status. The CK12 performed favorably in predicting response to pembro/SD101 compared to several other genomic signatures measuring intratumoral immune response. Higher CK12 also associates with response to the ANG1/2 inhibitor AMG386, an agent known to have immune modulatory activity. Higher CK12 was moderately associated with pCR in the control (OR=2.0/1SD), neratinib (OR=1.7/1SD), veliparib/carboplatin (OR=2.0/1SD), ganitumab (OR= 1.7/1SD) and TDM1/P arms (OR=2.1/1SD). Within the HR+HER2- subset, CK12 associated with pCR in all three IO arms, and in the control, AMG386, ganitumab, and ganetespib arms. Within the smaller TN subset, it associated with response in pembro and pembro/SD101 arms but not in durva/olaparib, and in the neratinib and AMG386 arms. Chemokine12 mostly did not associate with pCR in HER2+ subsets, except for HR+HER2+ patients treated with neratinib, and HR-HER2+ patients in the original control arm (trastuzumab). Conclusion: The CK12 signature is highly predictive of complete pathologic response to immuno-oncology agents and other therapeutics supporting the role of the crosstalk within the tumor immune microenvironment in predicting response across subtypes. This gene expression signature can be readily obtained from microarrays and warrants further investigation in future arms of ISPY2 as a predictive biomarker.

Citation Format: Hatem Soliman, Denise Wolf, Jo Chien, Christina Yau, Michael Campbell, Mark Magbanua, Ruixiao Lu, Nicholas O'Grady, Lamorna Brown-Swigart, Gillian Hirst, Beverly Parker, Laura Sit, Smita Asare, Doug Yee, Angie DeMichele, Rita Nanda, Lajos Pusztai, Don Berry, Laura Esserman, Laura Van't Veer. Chemokine12 (CK12) tertiary lymphoid gene expression signature as a predictor of response in 3 immunotherapy arms of the neoadjuvant ISPY 2 TRIAL - pembrolizumab with and without SD101, and durvalumab combined with olaparib - and in 9 other arms of the trial including platinum-based and dual-anti-HER2 therapies [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD10-07.

Improvement in colorectal cancer outcomes over time is limited to patients with left-sided disease

PURPOSE

Incidence and mortality of colorectal cancer (CRC) declined over the last decades. However, survival depends on the primary tumor location. It is unknown if all progress in outcomes vary depending on left-sided (LCRC) versus right-sided (RCC) colorectal cancer. We compare incidence and mortality rates over time according to the primary tumor location.

METHODS

Data from the Austrian National Cancer Registry spanning from 1983 to 2018 were used to calculate annual incidence and mortality rates and survival stratified by primary tumor localization and stage. Joinpoint regression with linear regression models were used on different subgroups to identify significant changes of incidence- and mortality slopes.

RESULTS

A total of 168,260 (incidence dataset) and 87,355 cases (mortality dataset) were identified. Survival of disseminated RCC was worse compared to LCRC (HR 1.14; CI 1.106-1.169). Total and LCRC incidence and mortality rates declined steadily over time, whereas the rates of RCC did not. Incidence of disseminated RCC declined significantly less (slope - 0.07; CI - 0.086; - 0.055) than in LCRC (slope - 0.159; CI - 0.183; - 0.136); mortality rate of RCC was unchanged over time. Incidence and mortality of localized RCC remained unchanged over time, whereas both rates declined independently of stage in LCRC.

CONCLUSION

Colorectal cancer outcomes during the last 35 years have preferentially improved in LCRC but not in RCC, indicating that the progress made is limited to LCRC. It is necessary to define RCC as a distinct form of CRC and to focus on specific strategies for its early detection and treatment.

Integrative single cell RNA-sequencing descrambles a substantial divergence of adaptive immune cell identities and transcriptional programs in mouse and human atherosclerosis

Aims

The distinct function of immune cells in human atherosclerosis has been mostly defined by preclinical mouse studies. Contrastingly, the immune cell composition of human atherosclerotic plaques and their contribution to disease progression is only poorly understood. It remains uncertain whether genetic animal models allow for valuable translational approaches.

Methods and results

We performed single cell RNA-sequencing (scRNAseq) to define the immune cell landscape in human carotid atherosclerotic plaques. The human immune cell repertoire was dominated by T cells with a considerable inter-patient variability and an unexpected heterogeneity. We performed bioinformatical integration with 7 mouse data sets and discovered a total of 38 cellular identities, of which some were not conserved between species and exclusively found in mice or humans. Locations, frequencies, and transcriptional programs of immune cells in preclinical mouse models did not resemble the immune cell landscape in human atherosclerosis. In contrast to mice, human plaques were not myeloid- and B cell-dominated and instead contained several T cell phenotypes with hallmarks of T cell memory, dysregulation, exhaustion, and activation. Human immune cells were predominantly enriched for transcriptional programs of hypoxia, glucose, and autoimmunity. In a validation cohort of 43 patients activated immune cell subsets defined by multi-colour flow cytometry associated with cerebral ischemia and coronary artery disease.

Conclusion

Here, we uncover yet undefined immune cell types associating with clinical disease. This leukocyte atlas of human atherosclerosis builds the conceptual basis for subsequent identification of cellular targets for clinical immunomodulatory therapies and risk prediction.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ERC Starting Grant

A protein interaction landscape of breast cancer

[Figure: see text].

Ovarian follicular function is not altered by SARS-CoV-2 infection or BNT162b2 mRNA COVID-19 vaccination

STUDY QUESTION

Does the immune response to coronavirus disease 2019 (COVID-19) infection or the BNT162b2 mRNA vaccine involve the ovarian follicle, and does it affect its function?

SUMMARY ANSWER

We were able to demonstrate anti-severe acute respiratory syndrome coronavirus 2 (SARS–CoV-2) IgG in follicular fluid (FF) from both infected and vaccinated IVF patients, with no evidence for compromised follicular function.

WHAT IS KNOWN ALREADY

No research data are available yet.

STUDY DESIGN, SIZE, DURATION

This is a cohort study, composed of 32 consecutive IVF patients, either infected with COVID-19, vaccinated or non-exposed, conducted between 1 February and 10 March 2021 in a single university hospital-based IVF clinic.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A consecutive sample of female consenting patients undergoing oocyte retrieval was recruited and assigned to one of the three study groups: recovering from confirmed COVID-19 (n = 9); vaccinated (n = 9); and uninfected, non-vaccinated controls (n = 14). Serum and FF samples were taken and analyzed for anti-COVID IgG as well as estrogen, progesterone and heparan sulfate proteoglycan 2 concentration, as well as the number and maturity of aspirated oocytes and day of trigger estrogen and progesterone measurements. Main outcome measures were follicular function, including steroidogenesis, follicular response to the LH/hCG trigger, and oocyte quality biomarkers.

MAIN RESULTS AND THE ROLE OF CHANCE

Both COVID-19 and the vaccine elicited anti-COVID IgG antibodies that were detected in the FF at levels proportional to the IgG serum concentration. No differences between the three groups were detected in any of the surrogate parameters for ovarian follicle quality.

LIMITATIONS, REASONS FOR CAUTION

This is a small study, comprising a mixed fertile and infertile population, and its conclusions should be supported and validated by larger studies.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first study to examine the impact of SARS–Cov-2 infection and COVID-19 vaccination on ovarian function and these early findings suggest no measurable detrimental effect on function of the ovarian follicle.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded out of an internal budget. There are no conflicts of interest for any of the authors.

TRIAL REGISTRATION NUMBER

CinicalTrials.gov registry number NCT04822012.

Layered van der Waals Topological Metals of TaTMTe4 (TM = Ir, Rh, Ru) Family

Layered van der Waals materials of the family TaTMTe₄ (TM = Ir, Rh, Ru) are showing interesting electronic properties. We report the growth and characterization of TaIrTe₄, TaRhTe₄, TaIr_1-xRh_xTe₄ (x = 0.06, 0.14, 0.78, 0.92), Ta_1+xRu_1-xTe₄ single crystals. X-ray powder diffraction confirms that TaRhTe₄ is isostructural to TaIrTe₄. All these compounds are metallic with diamagnetic behavior. Below T ≈ 4 K we observed signatures of the superconductivity in the TaIr_1-xRh_xTe₄ compounds for x = 0.92. All samples show weak quadratic-in-field magnetoresistance (MR). However, for TaIr_1-xRh_xTe₄ with x ≈ 0.78, the MR has a linear term dominating in low fields that indicates the presence of Dirac cones in the vicinity of the Fermi energy. For TaRhTe₄ series the MR is almost isotropic. Electronic structure calculations for TaIrTe₄ and TaRhTe₄ reveal appearance of the Rh band close to the Fermi level.

Abstract 2308: The protein interaction landscape of breast cancer

Cancers have been associated with a diverse array of genomic alterations, many of which are rare with unknown significance. To understand the cellular mechanisms impacted by such alterations in breast invasive carcinoma, we have applied affinity-purification mass spectrometry to delineate comprehensive biophysical interaction networks for 40 frequently altered breast cancer proteins across three human breast cell lines, providing a novel resource of context-specific and shared protein-protein interaction networks in breast cancer cells. These networks interconnect and enrich for common and rare cancer mutations, and are substantially rewired by mutations. Our analysis identifies novel PIK3CA-interacting proteins which repress AKT signaling, and UBE2N emerges as a BRCA1 interactor predictive of clinical response to PARP inhibition. We also show that Spinophilin interacts with and dephosphorylates BRCA1 to promote DNA double-strand break repair. Thus, cancer protein interaction landscapes provide a framework for recognizing oncogenic drivers and drug vulnerabilities.

Citation Format: Minkyu Kim, Jisoo Park, Mehdi Bouhaddou, Kyumin Kim, Ajda Rojc, Maya Modak, Margaret Soucheray, Patrick O'Leary, Denise Wolf, Dominique C. Mitchell, Fan Zheng, John D. Gordan, Jean-Philippe Coppé, Danielle L. Swaney, Laura van' t Veer, Alan Ashworth, Trey Ideker, Nevan J. Krogan. The protein interaction landscape of breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2308.

PRoBE the cloud toolkit: finding the best biomarkers of drug response within a breast cancer clinical trial

Objectives

In this paper, we discuss leveraging cloud-based platforms to collect, visualize, analyze, and share data in the context of a clinical trial. Our cloud-based infrastructure, Patient Repository of Biomolecular Entities (PRoBE), has given us the opportunity for uniform data structure, more efficient analysis of valuable data, and increased collaboration between researchers.

Materials and Methods

We utilize a multi-cloud platform to manage and analyze data generated from the clinical Investigation of Serial Studies to Predict Your Therapeutic Response with Imaging And moLecular Analysis 2 (I-SPY 2 TRIAL). A collaboration with the Institute for Systems Biology Cancer Gateway in the Cloud has additionally given us access to public genomic databases. Applications to I-SPY 2 data have been built using R Shiny, while leveraging Google's BigQuery tables and SQL commands for data mining.

Results

We highlight the implementation of PRoBE in several unique case studies including prediction of biomarkers associated with clinical response, access to the Pan-Cancer Atlas, and integrating pathology images within the cloud. Our data integration pipelines, documentation, and all codebase will be placed in a Github repository.

Discussion and conclusion

We are hoping to develop risk stratification diagnostics by integrating additional molecular, magnetic resonance imaging, and pathology markers into PRoBE to better predict drug response. A robust cloud infrastructure and tool set can help integrate these large datasets to make valuable predictions of response to multiple agents. For that reason, we are continuously improving PRoBE to advance the way data is stored, accessed, and analyzed in the I-SPY 2 clinical trial.

Abstract PD9-04: Identification of biomarkers associated with therapeutic resistance: Quantitative protein/phosphoprotein analysis of ~750 patients across 8 arms of the neoadjuvant I-SPY 2 TRIAL for high-risk early stage breast cancer

Background: The goal of I-SPY 2 is to rapidly test novel therapies in addition to standard of care in high-risk breast cancer patients. It has resulted in increasing response rates, where pCR rates in TNBC and HR-HER2+ subsets have reached ~60% and ~75%, respectively. Yet, there remains a sizeable subset of non-responders, especially among HR+ patients. Identification of ‘universal’ resistance mechanisms may guide rational selection of agents to improve these patient's outcomes. Thus, we analyzed reverse phase protein array (RPPA) based quantitative protein/phosphoprotein data across arms to assess whether there are common mechanisms rendering these cancers resistant to all agent classes tested to date. Methods: 736 patients (260 HR+HER2-, 252 TN, 142 HR+HER2-, and 82 HR-HER2+; over 8 arms: 194 Ctr, 105 neratinib (N), 63 veliparib/carboplatin (VC), 128 AMG386 (anti-ANG1/2), 87 MK2206 (anti-AKT), 43 TH/pertuzumab (P), 49 TDM1/P, and 67 pembrolizumab (Pembro)) with pCR and RPPA data at the pre-treatment time point were considered for this analysis. 141 RPPA endpoints representing key cancer pathways were assessed for association with pCR using logistic regression modeling, with HR, HER2 and treatment arm as covariates (likelihood ratio test; p<0.05). Analysis was also performed in HR/HER2 subsets and within treatment arms. Markers were analyzed individually; multiple comparison correction (Benjamini-Hochberg) was applied to p-values. Our analysis is exploratory, and does not adjust for other biomarkers outside this study. Results: Prior to FDR correction, high levels of Cyclin D1, a cell cycle protein implicated in estrogen-mediated DNA damage repair, associate with non-pCR in the population as a whole and within all subtypes except for the HR-HER2+ subset; an association that retains significance after FDR correction overall as well as in HER2- and HR+HER2- subsets. Within individual arms, high Cyclin D1 predicted non-response in VC, control, and AMG386; and trends toward association in Pembro and N. In addition, high quantitative ER and phospho-androgen receptor (pAR; S650) associate with non-pCR in the population as a whole and in the HR+HER2- subset. For both ER and pAR the strongest association with non-pCR was in the Pembro arm. Candidates for universal sensitivity signals include immune proteins JAK-STAT (pSTAT5 (Y694) and pSTAT1 (Y701)) overall; and pERBB2/pEGFR for HER2+ patients. Conclusions: High levels of Cyclin D1, but not other cell cycle proteins, predict non-response to chemo-/targeted-therapy across arms and subtypes, suggesting that agents specifically targeting Cyclin D1 may increase chemo-sensitivity. ER/phospho-AR as global resistance signals suggest inclusion of anti-AR agents in combination therapy, and the need for new endocrine-based approaches.

Citation Format: Julia Wulfkuhle, Denise Wolf, Christina Yau, Lamorna Brown-Swigart, Rosa I Gallagher, Gillian Hirst, Laura Sit, Smita Asare, I-SPY 2 TRIAL Investigators, Nola Hylton, Angela DeMichele, Douglas Yee, Jo Chien, Hope Rugo, John Park, Kathy Albain, Rita Nanda, Debu Tripathy, Richard Schwab, Don Berry, Laura Esserman, Laura van t' Veer, Emanual Petricoin, III. Identification of biomarkers associated with therapeutic resistance: Quantitative protein/phosphoprotein analysis of ~750 patients across 8 arms of the neoadjuvant I-SPY 2 TRIAL for high-risk early stage breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD9-04.

Abstract PD9-02: Personalized ctDNA as a predictive biomarker in high-risk early stage breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC) with or without pembrolizumab (P)

Background: In the I-SPY 2 TRIAL, the addition of P to standard NAC resulted in more than doubling of the pathologic complete response (pCR) rates for both hormone receptor-positive (HR+)/HER2- and triple-negative (TN) early breast cancer (EBC) patients (pts) compared to NAC only (Nanda et al, JAMA Oncol, 2020). At 3 years, distant recurrence-free survival (DRFS) rates in pts with pCR following NAC+P was >95%. We hypothesized that ctDNA can serve as a predictive biomarker of response and survival in pts treated with NAC.

Methods: A personalized ctDNA test (Signatera) was performed on 511 serial plasma samples from 138 pts with high-risk HR+/HER2- (n=77) or TN (n=61) stage II/III EBC. Pts received P with paclitaxel (Tx) followed by AC (P arm, n=42) or standard NAC only (n=96), an exploratory subset of pts evaluated for P efficacy. Plasma was collected; pretreatment (T0), 3 weeks after treatment initiation (T1), between Tx+/-P and AC regimens (T2), and prior to surgery (T3). ctDNA was deemed positive with a minimum of 2 of the pt specific tumor mutation fragments detected in cfDNA. Association of ctDNA with response and survival was analyzed using logistic and Cox regressions with pCR and DRFS as endpoints. Median follow-up was 2.8 years.

Results: Detection of ctDNA decreased over time (P arm: T0-81%, T1-50%, T2-19%, T3-3%) and NAC only: T0-82%, T1-65%, T2-26%, T3-10%).

ctDNA data at T0 and T1 was available for 96% (132/138) of pts in P arm or NAC only (Table). Among ctDNA+ patients at baseline, clearance at T1 was significantly associated with pCR (OR=1.92, ctDNA+/-; OR=0.27, ctDNA+/+; LR p<0.001). This association remained significant after adjustment for HR status and treatment (LR p<0.001) and P arm or NAC only (P: LR p=0.03; NAC: LR p=0.01).

ctDNA data at T0, T1, and T2 was available for 86% (118/138) pts. (Table). Among all ctDNA+ pts at baseline, dynamics through T2 was associated with pCR (OR=1.44, ctDNA+/-/-; OR=0.33, ctDNA+/+/-, OR=0.12, ctDNA+/+/+; LR p=0.0011). This association remained significant when adjusted for HR status and treatment (LR p<0.001). Analysis within individual treatments showed significant association for NAC (LR p=0.040) and a non-significant trend in NAC+P (LR p=0.063), likely due to smaller sample size.

All pts who achieved pCR were ctDNA- at T3 (n=34). Among those who failed to achieve pCR (n=81), DRFS was significantly better in ctDNA- (n=72/81; 20 in P and 52 in NAC) versus ctDNA+ pts (n=9/81; 1 in P and 8 in NAC) (adjusted HR 0.13; 95% CI 0.05-0.37).

Conclusions: These exploratory results align with our previous findings that early clearance of ctDNA during NAC treatment was significantly associated with increased likelihood of achieving pCR. Additionally, we show that ctDNA clearance can be an early surrogate marker for therapy response assessment. Residual ctDNA after neoadjuvant treatment was a significant predictor of metastatic recurrence and death. Personalized monitoring of ctDNA during the course of NAC is feasible and provides information that can be combined with imaging and pathology, and may help to optimize decision making for de-escalation or escalation of therapy. Larger studies are ongoing.

ctDNA dynamics and pCRctDNA status at T0 and T1 (n=132)ctDNA status at T0, T1, and T2 (n=118)ctDNA-/-ctDNA+/-ctDNA+/+ctDNA-/-/-ctDNA+/-/-ctDNA+/+/-ctDNA+/+/+Total, n (%)24 (18)28 (21)80 (61)22 (19)24 (20)43 (36)27 (23)pCR, n (%)9 (38)15 (54)11 (14)9 (41)12 (50)8 (19)2 (7)No pCR, n (%)15 (63)13 (46)69 (86)13 (59)12 (50)35 (81)25 (93)

Citation Format: Mark Jesus M Magbanua, Denise Wolf, Derrick Renner, Svetlana Shchegrova, Lamorna Brown Swigart, Christina Yau, Gillian Hirst, Hsin-Ta Wu, Ekaterina Kalashnikova, Antony Tin, Amy Delson, Douglas Yee, Angela DeMichele, Raheleh Salari, Angel Rodriguez, Bernhard Zimmermann, Himanshu Sethi, Alexey Aleshin, Paul Billings, Laura Esserman, Minetta Liu, Rita Nanda, Laura van ‘t Veer, I-SPY 2 Investigators. Personalized ctDNA as a predictive biomarker in high-risk early stage breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC) with or without pembrolizumab (P) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD9-02.

Abstract PS11-04: Computational drug repositioning for the identification of new agents to sensitize drug-resistant breast tumors across treatment arms and molecular subtypes

Introduction: One of the principal limiting factors to achieving cures in patients with cancer is drug resistance. Drug repositioning is the application of FDA-approved drug compounds for novel indications beyond the scope of the drug’s original intended use. This approach offers advantages over traditional drug development by reducing development costs and providing shorter paths to approval, as drug safety has already been established during the drug’s original regulatory process. One approach for computational drug repositioning involves generating a disease gene expression signature and then identifying a drug that can reverse this disease signature. In this study, we extracted drug resistance signatures from the I-SPY 2 TRIAL by comparing gene expression profiles of responder and non-responder patients stratified by treatment and molecular subtype. We then applied our drug repositioning pipeline to predict compounds that can reverse the gene expression profiles of these drug resistance signatures. We hypothesize that reversing these drug resistance signatures will resensitize tumors to treatment and improve patient outcome.

Methods: We first generated the drug resistance signatures by performing differential expression between responders (RCB 0/I) and non-responders (RCB III) within treatment arms and molecular subtypes. An optimal log fold-change cutoff was selected for each signature by identifying the cutoff that best separates the responder and non-responder samples using k-means clustering. We then applied our drug repositioning pipeline to identify compounds that significantly reverse these signatures using the drug perturbation profiles generated in a breast cancer cell line in the Connectivity Map v2 dataset. Briefly, the pipeline uses a non- parametric, rank-based pattern-matching strategy based on the Kolmogorov-Smirnov (KS) statistic to assess the enrichment of resistance genes in a ranked drug gene expression list. Significance of each prediction is estimated from a null distribution of scores generated from random gene signatures.

Results: We found that few individual genes are shared among the resistance signatures across the treatment arms and molecular subtypes, with the most common genes present in only 5/17 of the treatment arm and molecular subtype groups. At the pathway-level, however, we found that immune-related pathways are generally enriched among the responders and estrogen-response pathways are generally enriched among the non-responders. Although most of our drug predictions are unique to treatment arms and molecular subtypes, our drug repositioning pipeline identified the selective estrogen receptor degrader (SERD) fulvestrant as a compound that can potentially reverse resistance across a majority of the treatment arms and molecular subtypes.

Conclusion: We applied our drug repositioning pipeline to identify novel agents to sensitize drug-resistant tumors in the I-SPY 2+ clinical trial and identified a SERD, fulvestrant, as a potential candidate for multiple molecular subtypes and treatment arms.

Citation Format: Katharine Yu, Amrita Basu, Christina Yau, Denise Wolf, Gillian Hirst, Laura Sit, Nicholas O’Grady, Thelma Brown, I-SPY 2 TRIAL Investigators, Angela DeMichele, Don Berry, Nola Hylton, Doug Yee, Laura Esserman, Laura van 't Veer, Marina Sirota. Computational drug repositioning for the identification of new agents to sensitize drug-resistant breast tumors across treatment arms and molecular subtypes [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS11-04.

Germline genetic contribution to the immune landscape of cancer

Understanding the contribution of the host's genetic background to cancer immunity may lead to improved stratification for immunotherapy and to the identification of novel therapeutic targets. We investigated the effect of common and rare germline variants on 139 well-defined immune traits in ∼9000 cancer patients enrolled in TCGA. High heritability was observed for estimates of NK cell and T cell subset infiltration and for interferon signaling. Common variants of IFIH1, TMEM173 (STING1), and TMEM108 were associated with differential interferon signaling and variants mapping to RBL1 correlated with T cell subset abundance. Pathogenic or likely pathogenic variants in BRCA1 and in genes involved in telomere stabilization and Wnt-β-catenin also acted as immune modulators. Our findings provide evidence for the impact of germline genetics on the composition and functional orientation of the tumor immune microenvironment. The curated datasets, variants, and genes identified provide a resource toward further understanding of tumor-immune interactions.

P2Y12-dependent regulation of emergency hematopoiesis after myocardial infarction

Introduction

Inflammation is essential for wound healing after myocardial infarction (MI). Leukocytes, especially neutrophils and monocytes, orchestrate removal of necrosis and regulation of tissue remodeling. Beside local recruitment from the blood, leukocyte supply via increased hematopoiesis is of major relevance for post-ischemic myocardial inflammation. Little is known about the pathways that carry the signals for increased demand for leukocytes from the site of injury to upstream hematopoietic stem cells (LSK) in the bone marrow (BM). In this study, we investigate the role of the P2Y12-ADP-receptor mediated regulation for emergency hematopoiesis after MI.

Methods

For standardized MI, a model of permanent coronary ligation was used in C57/Bl6 and P2Y12−/− mice. Changes in plasmatic ADP levels after MI were screened using ELISA, whereas the expression of the P2Y12-ADP-receptor in cell populations isolated from the BM was investigated by qPCR. CFU assays added further functional insight on hematopoietic proliferation in vitro. The effect of P2Y12 on the hematopoietic system after MI was investigated by inhibiting the P2Y12-receptor via prasugrel and compared to inhibition of the thromboxane pathway via acetylsalicylic acid (ASA). Proliferation of LSK in BM and leukocyte composition in blood, BM and infarct tissue after MI were assessed via FACS. Leukocyte composition in the infarcted myocardium was validated by immunohistochemistry. Finally, left ventricular function (LV-EF) and remodeling were investigated by echocardiography.

Results

24 h after MI, we found a peak of plasmatic ADP levels. LSK as upstream hematopoietic progenitors in the BM express a P2Y12-receptor, which was validated on transcriptional and protein level. Whereas ADP stimulation of LSK led to significantly larger colony growth in vitro on the one hand, percentage of cycling LSK were significantly reduced 48 h after MI in P2Y12−/− mice compared to WT mice, assessed by Ki67/DAPI cell cycle analysis. Prasugrel treatment showed similar effects, translating into reduced numbers of downstream hematopoietic progenitors GMP and MDP 72 h after MI. Treatment with ASA however had no significant effect neither on cycling LSK nor progenitor populations. Consequently, decreased medullary hematopoiesis under P2Y12-inhibition led to reduced infiltration of inflammatory cells in the infarct tissue 7 days after MI, finally resulting in significantly improved outcome in terms of LV-EF 3 weeks after MI.

Conclusion

In this study, we demonstrate that P2Y12-mediated signaling is involved in emergency hematopoiesis after MI and advocates post-MI inflammation. In turn, inhibition of P2Y12-mediated signaling contributes to improved wound healing and prevention of adverse cardiac remodeling after MI, which adds a yet unknown mechanism to the success story of modern P2Y12-receptor blockers.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft

Atlas of the immune cell repertoire in human atherosclerotic plaques characterized by single cell RNA-sequencing and multi-color flow cytometry

Rationale

Atherosclerosis is a chronic inflammatory disease that is driven by the accumulation of pro- and anti-inflammatory leukocytes in the intima of affected arteries. Yet, the cellular composition of human atherosclerotic plaques is only poorly understood. Here, we characterized immune cells to human carotid atherosclerotic plaques by multi-color flow cytometry and scRNAseq.

Methods and results

First, we compared a set of previously reported digestion protocols to liberate leukocytes from human carotid plaques after surgical thrombendarteriectomy. One digestion cocktail, containing Collagenase IV and DNase I, was superior regarding cell survival and cell surface marker preservation. Second, leukocytes from 56 surgical specimen were characterized by flow cytometry with a set of 16 parameters and cell surface markers capable of identifying principal hematopoietic leukocyte lineages. This protocol allowed to extract and analyze on average 4x103 viable CD45+ leukocytes from a mean of 988 mg plaque tissue. Surprisingly, we found that atherosclerotic plaques were dominated by T cells with 33.7±2.2% CD4+ T-helper cells and 25.6±2.5% CD8+ cytotoxic T cells. CD11b+ myeloid cells, including monocytes and macrophages, represented only 20.2±4.0% of all CD45+ leukocytes. CD19+B cells and CD56+ NK-cells accounted for 3.9±1.2 and 3.3±0.5%, respectively. TCR-g/d+ T cells and neutrophils were undetectable in atherosclerotic plaques. This cellular composition differed significantly from peripheral blood, but was not relevantly changed between different plaque locations, indicating that macrophage-rich necrotic cores mostly contain dead cells. We confirmed the principal composition of human plaques by single-cell RNA-sequencing from six patients. To allow an estimation of cellular heterogeneity independent of classical cell surface marker assignment, we performed an unsupervised cluster detection algorithm by t-distributed stochastic neighbor embedding (tSNE) and found more than 16 leukocyte clusters with unique cell surface marker expression, suggesting an unexpected high diversity of plaque leukocytes.

Conclusion

We developed an immune cell phenotyping protocol optimized for human carotid plaques. The definition of phenotypes and frequencies in atherosclerotic plaques will allow to build clinical associations between the immune cell composition and clinical outcomes in future.

Funding Acknowledgement

Type of funding source: None

Macrophage-specific IRF5 deficiency stabilizes atherosclerotic plaques in ApoE−/− mice

Background

Interferon regulatory factor (IRF) 5 is a transcription factor promoting inflammatory macrophage polarization (M1 type). Given the central role of macrophages in atherosclerotic plaque development we hypothesized that macrophage specific deletion of IRF5 will protect from atherosclerosis.

Purpose

Investigate whether intrinsic blockade of M1 macrophage polarization ameliorates atherosclerosis

Methods

Female ApoE−/−LysMCre/wtIRF5flox/floxand ApoE−/−LysMwt/wtIRF5flox/floxmice were fed a high cholesterol diet for 3 months, and atherosclerotic plaque size and compositions as well as inflammatory gene expression were analyzed. Mechanistically, IRF5-dependend bone marrow derived macrophage cytokine profiles were tested under M1 and M2 polarizing conditions. Aortic macrophage chimerism in irradiated ApoE−/− mice reconstituted with a mixture of CD45.1+ ApoE−/− (WT) and CD45.2+ ApoE−/− LysMCre/WtIRF5flox/flox(KO) bone marrow was evaluated to distinguish systemic from intra-plaque effects on monocyte/macrophage kinetics.

Results

Macrophage-specific IRF5 deficiency blunted LPS/IFNg-induced IL-1β and TNFα gene expression in vitro. In ApoE−/− mice, macrophage-specific IRF5 deficiency did not alter lesion size in the aortic root but significantly reduced macrophage and lipid contents by about 25% while increasing collagen deposition by over 30%. This was accompanied by relative reductions in gene expressions of pro-inflammatory (IL-1β, IL-6, IL-12) and increases in anti-inflammatory (Mertk, TGFβ, CD206) markers in atherosclerotic aortas of ApoE−/−LysMCre/wtIRF5flox/floxmice. When competing with IRF5 deficient cells in mixed irradiation bone marrow chimeras, IRF5 competent macrophages showed an advantage in accumulating in atherosclerotic aortas as disease progressed independent of monocyte recruitment.

Conclusion

Transcription factor IRF5 promotes a pro-inflammatory response in macrophages leading to vulnerable plaque formation and plaque destabilization, providing genetic evidence for targeting macrophage polarization in atherosclerosis.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): DFG

Autologous stem cell transplantation following simultaneous liver and kidney transplantation in severe amyloid light chain amyloidosis associated with multiple myeloma: a case report

Introduction

The involvement of vital organs in multiple myeloma (MM) with systemic amyloid light-chain (AL) amyloidosis can lead to acute organ failure. In this case, the fear of recurrence or progression of multiple myeloma often excludes those patients from undergoing organ transplantation. Nevertheless, clinically fit patients might benefit from a different therapeutic approach. This case presentation might highlight this particular unmet need and strengthen a different treatment approach.

Case presentation

To our knowledge, we present the first case of successful simultaneous liver and kidney transplantation, followed by autologous stem cell transplantation in a 60-year-old Caucasian male patient suffering from MM (Durie-Salmon stage IIB; ISS-stage: III, RISS stage: III) with primary AL amyloidosis. Chemotherapy treatment led to end-stage kidney disease requiring dialysis. Liver failure also occurred after at least three cycles of CyBorD (bortezomib, cyclophosphamide, and dexamethasone) of induction therapy with a good hematologic response. Over three years after the initial diagnosis, the patient is reportedly showing an excellent quality of life and a complete remission.

Discussion and Conclusion

We conclude that kidney and liver transplantation followed by autologous stem cell transplantation can be a treatment option for a selected group of patients with MM if AL amyloidosis is leading. In the end, the remission assessment by IMWG response criteria displayed a complete remission of MM together with complete reconstitution of organ functions (liver & renal function) as long as upfront clinical evaluation excludes significant cardiac involvement and other severe co-morbidities.

Eye Care in a Nursing Home

This article describes an example of an in-house eye care clinic for elderly nursing home residents. The success of this clinic is due not to any one person, but to the combined efforts of a team: a clinic supervisor, a nursing assistant, a medical assistant, an ophthalmic technician, and an ophthalmologist. The implications of providing good and effective eye care to nursing home residents are discussed.

Abstract P5-01-04: Personalized monitoring of circulating tumor DNA during neoadjuvant therapy in high-risk early stage breast cancer reflects response and risk of metastatic recurrence

Background: The detection of circulating tumor DNA (ctDNA) during neoadjuvant therapy (NAT) may serve as an early indicator of emerging resistance and disease progression. In this study, we analyzed ctDNA from high-risk early breast cancer patients who received NAT and definitive surgery in the I-SPY 2 TRIAL (NCT01042379). We hypothesized that ctDNA can serve as a biomarker of response and survival in this setting.

Methods: ctDNA analysis was performed on 291 plasma samples from 84 high-risk stage II and III breast cancer patients randomized either to an investigational agent MK-2206, an AKT inhibitor, in combination with paclitaxel followed by doxorubicin and cyclophosphamide (AC) (n=52)—or standard-of-care (paclitaxel followed by AC) (n=32). HER2+ patients also received trastuzumab. Serial plasma was collected at pretreatment (T0), at 3 weeks after initiation of paclitaxel treatment (T1), between paclitaxel and AC regimens (T2), and after NAT prior to surgery (T3).

A personalized ctDNA test was designed to detect a set of 16 patient-specific somatic variants, initially identified from whole exome sequencing of pretreatment tumor, then tested in plasma samples. Regions containing the somatic variants were amplified from cell-free DNA using specific polymerase chain reaction primers. Amplified products were subjected to ultra-deep sequencing (mean: 94,000x) to detect somatic variants. Association between ctDNA and clinicopathologic variables was assessed using Fisher’s exact test. Association of ctDNA with response and survival was analyzed using logistic and Cox regressions, respectively. The survival endpoint of the study was distant disease-free survival. The median follow-up was 4.8 years.

Results: At pretreatment (T0), 61 of the 84 (73%) patients had detectable ctDNA. Pretreatment (T0) ctDNA positivity and levels (mean mutant molecules per mL of plasma) were significantly associated with increased tumor burden (clinical T stage T3/T4), more aggressive tumor biology (higher Mammaprint scores) and subtype (HER2+ and Triple negative). CtDNA detection during NAT decreased over time (T0- 73%; T1- 35%; T2- 14%; T3- 9%).

Of the 84 patients, 23 (27%) achieved pCR and all were ctDNA-negative after NAT (T3), while all 6 patients who had detectable ctDNA at T3 did not achieve pCR. Patients who cleared ctDNA early at T1 (n=27, 48% pCR rate) had significantly increased probability of achieving a pathologic complete response (pCR) compared to those who remained ctDNA-positive (n=29, 17% pCR rate; Odds ratio=4.33, Likelihood ratio p=0.012).

Patients who were ctDNA-positive at T3 (n=6) had significantly increased risk of metastatic recurrence (HR 14.7; 95% CI 1.6-131.5) compared to those who achieved pCR and were ctDNA-negative (n=17). The risk of metastatic recurrence in patients who cleared ctDNA during NAT was not significantly different from those who were negative at T0 and remained negative by T3 (hazard ratio, HR: 2.1, 95% CI: 0.22-20.2). Interestingly, patients who were ctDNA-negative (n=37) but failed to achieve pCR had similar risk of metastatic recurrence with those who achieved pCR (HR 1.4; 95% CI 0.15-13.5).

Conclusions: Early clearance of ctDNA during NAT was significantly associated with increased likelihood of achieving pCR. Residual ctDNA after NAT was a significant predictor of metastatic recurrence, while clearance of ctDNA at any point during NAT was associated with improved outcomes. Taken together, personalized monitoring of ctDNA during NAT may aid in real-time assessment of treatment response and help fine-tune pCR as a surrogate endpoint of survival. Validation studies in a larger cohort are warranted.

Citation Format: Mark Jesus M Magbanua, Lamorna Brown-Swigart, Gillian Hirst, Christina Yau, Denise Wolf, Hsin-Ta Wu, Antony Tin, Svetlana Shchegrova, Himanshu Sethi, Raheleh Salari, Alexey Aleshin, Maggie Louie, Bernhard Zimmermann, Angela DeMichele, Minetta Liu, Amy Delson, Amy Jo Chien, Smita Asare, Laura Esserman, I-SPY 2 TRIAL Consortium, Laura van't Veer. Personalized monitoring of circulating tumor DNA during neoadjuvant therapy in high-risk early stage breast cancer reflects response and risk of metastatic recurrence [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-01-04.

Abstract P2-10-05: A breast cancer multi-racial/ethnic polygenic risk score for improved personalized breast cancer screening

Background: Polygenic risk scores (PRS) integrate risk information from breast cancer associated SNPs (single nucleotide polymorphism). The risk scores have mostly been developed in populations of European ancestry, and have been shown to improve risk prediction over standard breast cancer risk models in these populations. The ability of the PRS to personalize screening is currently being studied. We included PRS as a component of breast cancer risk assessment in the WISDOM Study, a trial of personalized vs. annual breast cancer screening. In order to account for race/ethnicity in PRS risk assessment, we developed a race/ethnicity calibrated and inclusive PRS risk score that we incorporated here into the Gail model to determine impact on risk stratification.

Methods: We constructed two different PRS for each race/ethnicity: For Caucasian populations, we constructed two PRS based on SNPs discovered in European-ancestry populations. One PRS was based on 167 SNPs (PRS-167) and the other based on 313 SNPs (PRS-313) from the Breast Cancer Association Consortium studies as previously published. For each of the Asian-, Hispanic- and African-ancestry populations we added additional ancestry specific SNPs to the PRS-167 or the PRS-313, that were literature curated or our own identified race/ethnicity SNPs that we validated to provide independent risk prediction for their ancestry group: Asian added 10 or 4 additional SNPs, Hispanic 2 SNPs, and African 8 and 12 SNPs, respectively to each model. We tested this approach using datasets from several case-control studies of multiple racial/ethnic populations and compared discrimination of the models using area under the receiver operating characteristic curve (AUROC). Furthermore, we applied our multi-racial/ethnic PRS-313 in a sample of ~3000 multi-racial/ethnic women from the Athena Breast Screening Registry, case-control sampled by Gail score to be at elevated (Gail >1.67) or average (Gail≤1.67) risk, to evaluate the impact of our multi-ethnic adjustment on risk stratification.

Results: A multi-race/ethnicity adjusted PRS-313 and PRS-167 plus ethnicity specific SNPs has moderate-high discriminatory power with AUROCs of 0.65 and 0.64, respectively. The specificity of our PRS-167 in the different race/ethnicity ancestries performs relatively well in Asian (AUROC 0.59) and Hispanic (AUROC 0.63) populations, but less so in African-ancestry (AUROC 0.56). Incorporating multi-race/ethnicity PRS into Gail model selected women, resulted in 20% of average-risk women transitioning to risk above 1.67%, and conversely, 38% of elevated risk patients were reclassified to average risk.

Conclusion: We constructed a PRS risk score that can be applied to multi-ethnic populations and found moderate-high discrimination. Additional work is needed for the African-ancestry population. The addition of a multi-race/ethnicity SNP model to risk classification based on the Gail model significantly changes risk stratification and clinical care recommendations due to down- or up-reclassification of women at average versus elevated risk.

Citation Format: Sarah Theiner, Donglei Hu, Scott Huntsman, Yiwey Shieh, Laura Fejerman, Irene Acerbi, Sarah D Sawyer, Paige Kendall, Wei Zheng, Dezheng Huo, Olufunmilayo I Olopade, Christopher Haiman, Karla Kerlikowske, Steven Cummings, Ester John, Gabriela Torres-Mejia, Lawrence H Kushi, Denise Wolf, Jeffery A Tice, David A Pearce, Laura Esserman, Athena Breast Health Network Investigators and Advocate Partners, Laura J van ‘t Veer, Elad Ziv. A breast cancer multi-racial/ethnic polygenic risk score for improved personalized breast cancer screening [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-10-05.

Androgen receptor gene expression in primary breast cancer

We studied androgen receptor (AR) gene expression in primary breast cancer (BC) to determine associations with clinical characteristics and outcomes in the I-SPY 1 study. AR was evaluated in I-SPY 1 (n = 149) using expression microarrays. Associations of AR with clinical and tumor features were determined using the Wilcoxon rank sum test (two-level factors) or the Kruskal-Wallis test (multi-level factors). We identified an optimal AR cut-point to maximize recurrence-free survival (RFS) differences between AR biomarker stratified groups, and assessed the association between the AR stratified groups and RFS using the Cox proportional hazard model. Pearson correlations between AR and selected genes were determined in I-SPY 1, METABRIC (n = 1992), and TCGA (n = 817). AR was lower in triple negative BC vs. hormone receptor positive (HR+)/HER2- and HER2+ disease (p < 0.00001), and lower in basal-like BC (p < 0.00001). AR was higher in grade I/II vs. III tumors (p < 0.00001), in patients >age 50 (p = 0.05), and in node negative disease (p = 0.006). Higher AR was associated with better RFS (p = 0.0007), which remained significant after receptor subtype adjustment (p = 0.01). AR correlated with expression of luminal, HER2, and steroid hormone genes. AR expression was related to clinicopathologic features, intrinsic subtype, and correlated with improved outcome.

P733Cholesterol uptake triggers macrophage proliferation in the plaque

Background

Guidelines recommend cholesterol lowering for primary and secondary prevention of cardiovascular disease. While lipid lowering has been reported to induce plaque regression, the underlying mechanisms have remained speculative.

Purpose

We hypothesize that lipid uptake triggers local macrophage proliferation in the plaque, and conversely, statin treatment inhibits local macrophage proliferation leading to plaque regression.

Methods

Mixed bone marrow chimeras were generated in LDLR−/− mice reconstituted with wild type and scavenger receptor deficient or cholesterol exporter deficient bone marrow cells to study cell autonomous effects on macrophage proliferation. APOE*3-Leiden.huCETP mice with established atherosclerosis were randomized to three groups: Continued cholesterol diet, cholesterol diet supplemented with 0.01% atorvastatin, and cholesterol free diet for 4 weeks to study mechanisms of plaque regression.

Results

Proliferation of scavenger receptor A and CD36 deficient macrophages with impaired lipid uptake was reduced by 30–50% in the plaque, while ABCA1/ABCG1 exporter deficiency resulted in cholesterol overloading and apoptosis. Oral atorvastatin treatment decreased total plasma cholesterol levels by 50% to the same extend as cholesterol free diet feeding in APOE*3-Leiden.huCETP. Cholesterol lowering resulted in a 50% reduction in local macrophage proliferation and plaque regression with reduced macrophage and lipid contents and increased collagen. GFP bone marrow reconstitution of APOE*3-Leiden.huCETP mice in which the aortas were shielded from irradiation showed infiltrating monocytes to contribute only 11% to the plaque macrophage pool during plaque progression, thereby underscoring the relevance of targeting macrophage proliferation for plaque regression. Finally, rates of macrophage proliferation in human carotid artery plaques correlated with serum LDL-cholesterol levels, in line with our experimental studies.

Conclusion

Foam cell formation in atherosclerotic plaques triggers their proliferation. Targeting macrophage proliferation leads to plaque regression.

P1939Tumor necrosis factor receptor-associated factor 5 (TRAF-5) deficiency exacerbates diet-induced adipose tissue inflammation and aggravates metabolic syndrome in mice

Introduction

Many clinical and experimental observations have established an association between visceral obesity and chronic adipose tissue inflammation. Potent pro-inflammatory mediators such as TNFα, CD40 and IL-1β are regulated by Tumor necrosis factor (TNF) receptor-associated factors (TRAFs). TRAF5 deficiency accelerates atherogenesis in mice by increasing inflammatory leukocyte recruitment. Since inflammatory cell invasion is also a prerequisite of adipose tissue inflammation, we tested the hypothesis that deficient TRAF5 signaling aggravates adipose tissue inflammation and its metabolic complications in a murine diet-induced obesity (DIO) model.

Purpose

We aimed to clarify the role of TRAF5 in adipose tissue inflammation and metabolic syndrome.

Methods

TRAF5−/− mice and gender- and age-matched wild-type (WT) mice consumed a high fat diet (HFD, 45%kcal from fat) or a matched low-fat diet (LFD, 10%kcal from fat) for 18 weeks to induce DIO and adipose tissue inflammation. All mice were then subjected to subsequent analysis, including glucose and insulin tolerance testing, body composition assessment by MRI imaging, flow cytometry, gene expression of different tissues, plasma analysis and histology. Finally, we studied if TRAF5 expression was associated with metabolic syndrome in humans by analyzing plasma and adipocytes samples from 62 patients of the Tumor-Necrosis-Factor Receptor Associated in Cardiovascular Risk Study (TRAFICS).

Results

TRAF5 expression was significantly attenuated in isolated WT-adipocytes and WT-macrophages after 18 weeks of HFD compared to LFD-fed controls. TRAF5−/− mice on HFD gained significantly more weight compared to TRAF5-competent mice and showed an aggravated metabolic phenotype, including impaired insulin tolerance, hyperinsulinemia and increased fasting glucose plasma levels. The weight gain in TRAF5−/− mice was attributable to a significant increase in adipose tissue and liver weight. Further analysis of the visceral adipose tissue revealed enhanced macrophage accumulation and increased pro-inflammatory CD11c+ subset polarization in HFD-fed TRAF5−/− mice. In line with an increased migratory capacity of inflammatory cells, we observed enhanced peritoneal invasion of leukocytes and subsets in TRAF5−/− mice. Accordingly, TRAF5 deficiency increased inflammatory cytokine expression and ameliorated parameters of insulin sensitivity in adipose tissue. Finally, patients with metabolic syndrome displayed decreased TRAF5 expression in blood and adipocytes compared to humans without metabolic syndrome.

Conclusion

We show that genetic deficiency of TRAF5 aggravates metabolic syndrome in murine diet-induced obesity. Enhanced accumulation of leukocytes subsets in adipose tissue serves as the likely mechanism. We conclude that TRAF5 signaling properties may favorably affect metabolic disease.

Acknowledgement/Funding

Forschungskommission Medizinische Fakultät Universität Freiburg, MOTI-VATE Promotionskolleg der Medizinischen Fakultät Freiburg (EKFS)

Randomized phase-II trial evaluating induction therapy with idarubicin and etoposide plus sequential or concurrent azacitidine and maintenance therapy with azacitidine

The aim of this randomized phase-II study was to evaluate the effect of substituting cytarabine by azacitidine in intensive induction therapy of patients with acute myeloid leukemia (AML). Patients were randomized to four induction schedules for two cycles: STANDARD (idarubicin, cytarabine, etoposide); and azacitidine given prior (PRIOR), concurrently (CONCURRENT), or after (AFTER) therapy with idarubicin and etoposide. Consolidation therapy consisted of allogeneic hematopoietic-cell transplantation or three courses of high-dose cytarabine followed by 2-year maintenance therapy with azacitidine in the azacitidine-arms. AML with CBFB-MYH11, RUNX1-RUNX1T1, mutated NPM1, and FLT3-ITD were excluded and accrued to genotype-specific trials. The primary end point was response to induction therapy. The statistical design was based on an optimal two-stage design applied for each arm separately. During the first stage, 104 patients (median age 62.6, range 18-82 years) were randomized; the study arms PRIOR and CONCURRENT were terminated early due to inefficacy. After randomization of 268 patients, all azacitidine-containing arms showed inferior response rates compared to STANDARD. Event-free and overall survival were significantly inferior in the azacitidine-containing arms compared to the standard arm (p < 0.001 and p = 0.03, respectively). The data from this trial do not support the substitution of cytarabine by azacitidine in intensive induction therapy.

Tumor Drug Penetration Measurements Could Be the Neglected Piece of the Personalized Cancer Treatment Puzzle

Precision medicine aims to use patient genomic, epigenomic, specific drug dose, and other data to define disease patterns that may potentially lead to an improved treatment outcome. Personalized dosing regimens based on tumor drug penetration can play a critical role in this approach. State-of-the-art techniques to measure tumor drug penetration focus on systemic exposure, tissue penetration, cellular or molecular engagement, and expression of pharmacological activity. Using in silico methods, this information can be integrated to bridge the gap between the therapeutic regimen and the pharmacological link with clinical outcome. These methodologies are described, and challenges ahead are discussed. Supported by many examples, this review shows how the combination of these techniques provides enhanced patient-specific information on drug accessibility at the tumor tissue level, target binding, and downstream pharmacology. Our vision of how to apply tumor drug penetration measurements offers a roadmap for the clinical implementation of precision dosing.

[Immunity and inflammation in atherosclerosis]

There is now overwhelming experimental and clinical evidence that arteriosclerosis is a chronic inflammatory disease. Lessons learned from genome-wide association studies, advanced in vivo imaging techniques, transgenic lineage tracing mice models and clinical interventional studies have shown that both innate and adaptive immune mechanisms can accelerate or curb arteriosclerosis. This article summarizes and discusses the pathogenesis of arteriosclerosis with a focus on the role of the adaptive immune system. Some limitations of animal models are discussed and the need for models that are tailored to better translate to human atherosclerosis and ultimately progress in prevention and treatment are emphasized.

Antibiotic resistant bacteria and resistance genes in biofilms in clinical wastewater networks

Increasing isolation rates of resistant bacteria in the last years require identification of potential infection reservoirs in healthcare facilities. Especially the clinical wastewater network represents a potential source of antibiotic resistant bacteria. In this work, the siphons of the sanitary installations from 18 hospital rooms of two German hospitals were examined for antibiotic resistant bacteria and antibiotic residues including siphons of showers and washbasins and toilets in sanitary units of psychosomatic, haemato-oncological, and rehabilitation wards. In addition, in seven rooms of the haemato-oncological ward, the effect of 24 h of stagnation on the antibiotic concentrations and MDR (multi-drug-resistant) bacteria in biofilms was evaluated. Whereas no antibiotic residues were found in the psychosomatic ward, potential selective concentrations of piperacillin, meropenem and ciprofloxacin were detected at a rehabilitation ward and ciprofloxacin and trimethoprim were present at a haemato-oncology ward. Antibiotic resistant bacteria were isolated from the siphons of all wards, however in the psychosomatic ward, only one MDR strain with resistance to piperacillin, third generation cephalosporins and quinolones (3MRGN) was detected. In contrast, the other two wards yielded 11 carbapenemase producing MDR isolates and 15 3MRGN strains. The isolates from the haemato-oncological ward belonged mostly to two specific rare sequence types (ST) (P. aeruginosa ST823 and Enterobacter cloacae complex ST167). In conclusion, clinical wastewater systems represent a reservoir for multi-drug-resistant bacteria. Consequently, preventive and intervention measures should not start at the wastewater treatment in the treatment plant, but already in the immediate surroundings of the patient, in order to minimize the infection potential.