Immunological characterization of a long-lasting response in a patient with metastatic triple-negative breast cancer treated with PD-1 and LAG-3 blockade

In patients with advanced triple-negative breast cancer (TNBC), translational research efforts are needed to improve the clinical efficacy of immunotherapy with checkpoint inhibitors. Here, we report on the immunological characterization of an exceptional, long-lasting, tumor complete response in a patient with metastatic TNBC treated with dual PD-1 and LAG-3 blockade within the phase I/II study CLAG525X2101C (NCT02460224) The pre-treatment tumor biopsy revealed the presence of a CD3+ and CD8+ cell infiltrate, with few PD1+ cells, rare CD4+ cells, and an absence of both NK cells and LAG3 expression. Conversely, tumor cells exhibited positive staining for the three primary LAG-3 ligands (HLA-DR, FGL-1, and galectin-3), while being negative for PD-L1. In peripheral blood, baseline expression of LAG-3 and PD-1 was observed in circulating immune cells. Following treatment initiation, there was a rapid increase in proliferating granzyme-B+ NK and T cells, including CD4+ T cells, alongside a reduction in myeloid-derived suppressor cells. The role of LAG-3 expression on circulating NK cells, as well as the expression of LAG-3 ligands on tumor cells and the early modulation of circulating cytotoxic CD4+ T cells warrant further investigation as exploitable predictive biomarkers for dual PD-1 and LAG-3 blockade.Trial registration: NCT02460224. Registered 02/06/2015.

Ecosystem degradation and the spread of Covid-19

The linkages between the emergence of zoonotic diseases and ecosystem degradation have been widely acknowledged by the scientific community and policy makers. In this paper we investigate the relationship between human overexploitation of natural resources, represented by the Human Appropriation of Net Primary Production Index (HANPP) and the spread of Covid-19 cases during the first pandemic wave in 730 regions of 63 countries worldwide. Using a Bayesian estimation technique, we highlight the significant role of HANPP as a driver of Covid-19 diffusion, besides confirming the well-known impact of population size and the effects of other socio-economic variables. We believe that these findings could be relevant for policy makers in their effort towards a more sustainable intensive agriculture and responsible urbanisation.

Predictors of fractional flow reserve/instantaneous wave-free ratio discordance: impact of tailored diagnostic cut-offs on clinical outcomes of deferred lesions

BACKGROUND

Patient-related and lesion-related factors may influence instantaneous wave-free ratio (iFR)/fractional flow reserve (FFR) concordance, potentially affecting the safety of revascularization deferral.

METHODS

Consecutive patients with at least an intermediate coronary stenosis evaluated by both iFR and FFR were retrospectively enrolled. The agreement between iFR and FFR at their diagnostic cut-offs (FFR 0.80, iFR 0.89) was assessed. Predictors of discordance were assessed using multivariate analyses. Tailored iFR cut-offs according to predictors of discordance best matching an FFR of 0.80 were identified. The impact of reclassification according to tailored iFR cut-offs on major cardiovascular events (MACE: cardiovascular death, myocardial infarction or target-lesion revascularization) among deferred lesions was investigated.

RESULTS

Two hundred and ninety-nine intermediate coronary stenosis [FFR 0.84 (0.78-0.89), iFR 0.91 (0.87-0.95), 202 left main/left anterior descending (LM/LAD) vessels, 67.6%] of 260 patients were studied. Discordance rate was 23.4% (n = 70, 10.7% iFR-negative discordant, 12.7% iFR-positive discordant). Predictors of discordance were LM/LAD disease, multivessel disease, non-ST-elevation myocardial infarction, smoking, reduced eGFR and hypertension. Lesion reclassification with tailored iFR cut-offs based on patient-level predictors carried no prognostic value among deferred lesions. Reclassification according to lesion location, which was entirely driven by LM/LAD lesions (iFR cut-offs: 0.93 for LM/LAD, 0.89 for non-LM/LAD), identified increased MACE among lesions deferred based on a negative FFR, between patients with a positive as compared with a negative iFR (19.4 vs. 6.1%, P = 0.044), whereas the same association was not observed with the conventional 0.89 iFR cut-off (15 vs. 8.6%, P = 0.303).

CONCLUSION

Tailored vessel-based iFR cut-offs carry prognostic value among FFR-negative lesions, suggesting that a one-size-fit-all iFR cut-off might be clinically unsatisfactory.

1 Dissecting β-catenin associated inflammation in patients with desmoid fibromatosis to identify prognostic biomarkers

Background

Desmoid fibromatosis (DF) is a locally aggressive rare tumor with high recurrence rate after surgery and unpredictable clinical course. Standard of care for DF patients is active surveillance; however, 30% of patients will progress and need active treatments. Biomarkers discriminating aggressive forms of DF are not available and prediction of progressing patients remains challenging. DF harbors mutations in β-catenin and a transcriptional ‘inflammatory phenotype’. Cancer-associated inflammation is fostered by systemic factors and detectable in circulating immune cells. Blood leukocytes thus represent a promising source of prognostic biomarkers for DF patients. In this study we investigate phenotypic and functional features of peripheral blood immune cells and molecular profile of DF biopsies to identify DF patients at risk of progression and guide tailored therapeutic approaches.

Methods

This is a prospective observational study enrolling patients with primary sporadic desmoid fibromatosis under active surveillance (n=80). Tumor and blood samples collected at diagnosis and during active surveillance will be studied by 1. transcriptomic analysis of DF biopsies; 2. multiparametric flowcytometry and functional profiling of blood cells; 3. RNA profiling of whole blood; 4. evaluation of plasma levels of cyto/chemokine and ctDNA of β-catenin variants. Levels of blood analytes will be correlated with patients‘ clinical outcome and integrated with immunological parameters.

Results

Peripheral blood immune profile of 42 cases and 17 healthy donors (HD) shows that DF patients display at baseline an altered myeloid profile compared to HD, which is maintained in a subset of patients during the first year of active surveillance. An increase in immunosuppressive activated granulocytes and granulocytic myeloid-derived suppressor cells, defined by differential co-expression of CD15, CD11b, CD16 and LOX1, is observed, concomitantly, with a boost of monocyte subsets, defined by co-expression of CD33, CD11b, CD14, CD16, HLA-DR and PDL1. Immunosuppressive low density granulocytes are increased in progressing patients compared to HD and regressors. Of note, a significant up-regulation of immunosuppressive PMN-MDSC (defined as CD15+LOX-1+) is observed in DF harboring T41A mutation, but not in S45 mutated DF.Transcriptomic data of DF biopsies and of plasma analytes are ongoing.

Conclusions

Systemic alterations of immunosuppressive and inflammatory myeloid cell subsets in peripheral blood of DF patients indicate that the inflammatory status detected at tumor site is reflected at systemic level. The altered myeloid profile supports the involvement of the immune system in DF onset and may represent a marker of disease aggressiveness.

Acknowledgements

Supported by Italian Ministry of Health (RF-2016-02362609).

Trial Registration

Not applicable.

References

Not applicable.

Ethics Approval

The study was conducted according to the guidelines of the Declaration of Helsinki, and approved by the Ethics Committee of Fondazione IRCCS Istituto Nazionale dei Tumori di Milano (protocol code INT85/10).

Consent

Written informed consent was obtained from the patient for publication of this abstract. A copy of the written consent is available for review by the Editor of this journal.

Extracellular vesicles in anti-tumor immunity

To what extent extracellular vesicles (EVs) can impact anti-tumor immune responses has only started to get unraveled. Their nanometer dimensions, their growing number of subtypes together with the difficulties in defining their origin hamper their investigation. The existence of tumor cell lines facilitated advance in cancer EV understanding, while capturing information about phenotypes and functions of immune cell EVs in this context is more complex. The advent of immunotherapy with immune checkpoint inhibitors has further deepened the need to dissect the impact of EVs during immune activation and response, not least to contribute unraveling and preventing the generation of resistance occurring in the majority of patients. Here we discuss the factors that influence anddrive the immune response in cancer patients in the context of cancer therapeutics and the roles or possible functions that EVs can have in this scenario. With immune cell-derived EVs as leitmotiv, we will journey from EV discovery and subtypes through physiological and pathological functions, from similarities with tumor EVs to measures to revert detrimental consequences on immune responses to cancer.

Molecular Determinants of Soft Tissue Sarcoma Immunity: Targets for Immune Intervention

Soft tissue sarcomas (STSs) are a family of rare malignant tumors encompassing more than 80 histologies. Current therapies for metastatic STS, a condition that affects roughly half of patients, have limited efficacy, making innovative therapeutic strategies urgently needed. From a molecular point of view, STSs can be classified as translocation-related and those with a heavily rearranged genotype. Although only the latter display an increased mutational burden, molecular profiles suggestive of an “immune hot” tumor microenvironment are observed across STS histologies, and response to immunotherapy has been reported in both translocation-related and genetic complex STSs. These data reinforce the notion that immunity in STSs is multifaceted and influenced by both genetic and epigenetic determinants. Cumulative evidence indicates that a fine characterization of STSs at different levels is required to identify biomarkers predictive of immunotherapy response and to discover targetable pathways to switch on the immune sensitivity of “immune cold” tumors. In this review, we will summarize recent findings on the interplay between genetic landscape, molecular profiling and immunity in STSs. Immunological and molecular features will be discussed for their prognostic value in selected STS histologies. Finally, the local and systemic immunomodulatory effects of the targeted drugs imatinib and sunitinib will be discussed.

Integrated transcriptional-phenotypic analysis captures systemic immunomodulation following antiangiogenic therapy in renal cell carcinoma patients

BACKGROUND

The combination of immune checkpoint blockade (ICB) with standard therapies is becoming a common approach for overcoming resistance to cancer immunotherapy in most human malignancies including metastatic renal cell carcinoma (mRCC). In this regard, insights into the immunomodulatory properties of antiangiogenic agents may help designing multidrug schedules based on specific immune synergisms.

METHODS

We used orthogonal transcriptomic and phenotyping platforms combined with functional analytic pipelines to elucidate the immunomodulatory effect of the antiangiogenic agent pazopanib in mRCC patients. Nine patients were studied longitudinally over a period of 6 months. We also analyzed transcriptional data from The Cancer Genome Atlas (TCGA) RCC cohort (N = 571) to assess the prognostic implications of our findings. The effect of pazopanib was assessed in vitro on NK cells and T cells. Additionally, myeloid-derived suppressor (MDSC)-like cells were generated from CD14+ monocytes transfected with mimics of miRNAs associated with MDSC function in the presence or absence of pazopanib.

RESULTS

Pazopanib administration caused a rapid and dramatic reshaping in terms of frequency and transcriptional activity of multiple blood immune cell subsets, with a downsizing of MDSC and regulatory T cells in favor of a strong enhancement in PD-1 expressing cytotoxic T and Natural Killer effectors. These changes were paired with an increase of the expression of transcripts reflecting activation of immune-effector functions. This immunomodulation was marked but transient, peaking at the third month of treatment. Moreover, the intratumoral expression level of a MDSC signature (MDSC INT) was strongly associated with poor prognosis in RCC patients. In vitro experiments indicate that the observed immunomodulation might be due to an inhibitory effect on MDSC-mediated suppression, rather than a direct effect on NK and T cells.

CONCLUSIONS

The marked but transient nature of this immunomodulation, peaking at the third month of treatment, provides the rationale for the use of antiangiogenics as a preconditioning strategy to improve the efficacy of ICB.

Immune contexture in high-risk soft tissue sarcomas (STS): A planned analysis of the ISG-STS-1001 randomized trial

11572

Background: The characteristics of immune contexture and its prognostic and predictive value in STS is left to be understood. This planned analysis of the ISG-STS-1001 trial, which compared neoadjuvant anthracycline + ifosfamide (AI) vs a histology-tailored (HT) chemotherapy (ChT), was aimed at characterizing the immune contexture after neoadjuvant ChT and investigating any association with the risk of recurrence. Methods: Patients registered in the ISG-STS-1001 study (ID: NCT01710176) were included if they had tumor tissue available for Tissue MicroArray (TMA), which was performed in the area of the surgical specimen with the highest lymphocyte infiltrate. The following markers were analyzed with IHC and measured quantitatively: CD3, CD8, PD1, GranzymeB, Foxp3, CD20, CD163, and PDL1. The T-Distributed Stochastic Neighboring Entities (t-SNE) analysis was used to account for the co-expression of IHC markers in each tumor. The prognostic value of each marker for disease-free survival (DFS) was assessed. Results: This analysis was conducted in 256 of 435 study patients. AI and HT neoadjuvant ChT did not result in any different distribution of immune contexture. Conversely, differences were observed between ‘complex’ karyotype STS (ck-STS: LMS, MPNST, UPS, MFS, pleomorphic liposarcoma, and pleomorphic rhabdomyosarcoma) and ‘simple’ karyotype STS (sk-STS: MLPS and SS). Ck-STS were enriched in both CD3+ and CD8+ cells compared to sk-STS. These cells displayed an heterogeneous distribution and were dispersed inside the tumor nest, keeping direct contact with sarcoma cells. Ck-STS also displayed an enrichment in Granzyme B+, and CD163+ cells. PDL1+ cells were occasionally identified and were more frequent in ck-STS, suggesting an immune-related expression. Most STS were negative for CD20+ cells, however, when present these cells were highly represented and organized in tertiary lymphoid-like structure. The t-SNE generated plot clustered tumors, the ‘cold’ mainly including sk-STS and the ‘hot’ mainly composed by ck-STS. In the ‘hot’ group, a cluster of tumors displayed an immune infiltrate enriched with a high number of CD3, CD8, GranzymeB, PD-1, and PDL-1+ cells. When the prognostic value of the immune markers was investigated, the presence of CD20+ cells was the only independent prognostic factor for DFS (HR=0.68, 95%CI 0.52-0.91) in a histology-stratified estimate adjusting for tumor size in cm (HR=1.07, 95%CI 1.03-1.12) and patient age (HR=1.0, 95%CI 0.97-1.02). Conclusions: Immune contexture differed across sarcoma histologies after neoadjuvant ChT, rather than across the two study arms, with ck-STS being marked by a rich immune contexture. While a CD20+ infiltrate was found to be an independent prognostic factor for a better outcome, further analyses are in progress on the prognosis of patients with the richest immune contexture. Clinical trial information: NCT01710176.

Back to simplicity: a four-marker blood cell score to quantify prognostically relevant myeloid cells in melanoma patients

Background

Myeloid-derived suppressor cells (MDSC), a cornerstone of cancer-related immunosuppression, influence response to therapy and disease outcomes in melanoma patients. Nevertheless, their quantification is far from being integrated into routine clinical practice mostly because of the complex and still evolving phenotypic signatures applied to define the cell subsets. Here, we used a multistep downsizing process to verify whether a core of few markers could be sufficient to capture the prognostic potential of myeloid cells in peripheral blood mononuclear cells (PBMC) of metastatic melanoma patients.

Methods

In baseline frozen PBMC from a total of 143 stage IIIc to IV melanoma patients, we first assessed the relevant or redundant expression of myeloid and MDSC-related markers by flow cytometry (screening set, n=23 patients). Subsequently, we applied the identified panel to the development set samples (n=59 patients undergoing first/second-line therapy) to obtain prognostic variables associated with overall survival (OS) and progression-free survival (PFS) by machine learning adaptive index modeling. Finally, the identified score was confirmed in a validation set (n=61) and compared with standard clinical prognostic factors to assess its additive value in patient prognostication.

Results

This selection process led to the identification of what we defined myeloid index score (MIS), which is composed by four cell subsets (CD14⁺, CD14⁺HLA-DR^neg, CD14⁺PD-L1⁺ and CD15⁺ cells), whose frequencies above cut-offs stratified melanoma patients according to progressively worse prognosis. Patients with a MIS=0, showing no over-threshold value of MIS subsets, had the best clinical outcome, with a median survival of >33.6 months, while in patients with MIS 1→3, OS deteriorated from 10.9 to 6.8 and 6.0 months as the MIS increased (p<0.0001, c-index=0.745). MIS clustered patients into risk groups also according to PFS (p<0.0001). The inverse correlation between MIS and survival was confirmed in the validation set, was independent of the type of therapy and was not interfered by clinical prognostic factors. MIS HR was remarkably superior to that of lactate dehydrogenase, tumor burden and neutrophil-to-lymphocyte ratio.

Conclusion

The MIS >0 identifies melanoma patients with a more aggressive disease, thus acting as a simple blood biomarker that can help tailoring therapeutic choices in real-life oncology.

Predictors of fractional flow reserve/instantaneous wave-free ratio discordance documented during functional coronary stenosis assessment: impact of tailored diagnostic cut-offs on long-term outcomes

Background

Patient- and lesion-related factors may influence concordance between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR), potentially affecting safety of revascularization deferral.

Methods

Consecutive patients with at least an intermediate coronary stenosis evaluated by both iFR and FFR were retrospectively enrolled. Revascularization was at physician's discretion. The agreement between IFR and FFR at their diagnostic cut-offs (FFR 0.80, iFR 0.89) according to patient- and lesion-level characteristics was assessed. Multivariate analyses were carried to identify the independent predictors of discordance. Tailored iFR cut-offs according to predictors of discordance best matching an FFR of 0.80 were identified by receiver-operating characteristic (ROC) curves. The impact of reclassification according to tailored iFR cut-offs on major cardiovascular events (MACE: cardiovascular death, myocardial infarction or target lesion revascularization) among deferred lesions was investigated.

Results

299 coronary stenosis (diameter stenosis 54±14%, FFR 0.84 [0.78–0.89], iFR 0.91 [0.87–0.95], left main/left anterior descending [LM/LAD] vessel 67.6%) of 260 patients were studied, and 46.5% were revascularized. Discordance rate was 23.4% (10.7% iFR-negative discordant, 12.7% iFR-positive discordant). Independent predictors of discordance were LM/LAD disease, multivessel disease, non-ST-elevation myocardial infarction presentation, smoking, reduced glomerular filtration rate and hypertension. Lesion reclassification with tailored iFR-cut-offs based on patient-level predictors carried no prognostic value among deferred lesions. Reclassification according to lesion location, which was entirely driven by LM/LAD lesions (iFR-cut-offs: 0.93 for LM/LAD, 0.89 for non-LM/LAD), identified increased MACE among lesions deferred based on a negative FFR, between patients with a positive as compared to a negative iFR (19.4% vs. 6.1%, p=0.044), while the same association was not observed with the conventional 0.89 iFR cut-off (15.0% vs 8.6%, p=0.303).

Conclusion

Tailored vessel-based iFR cut-offs carry prognostic value among FFR negative lesions, suggesting that iFR may more safely defer revascularization of LM/LAD lesions than FFR and that a single iFR cut-off might be clinically unsatisfactory.

Funding Acknowledgement

Type of funding source: None

microRNAs Shape Myeloid Cell-Mediated Resistance to Cancer Immunotherapy

Immunotherapy with immune checkpoint inhibitors can achieve long-term tumor control in subsets of patients. However, its effect can be blunted by myeloid-induced resistance mechanisms. Myeloid cells are highly plastic and physiologically devoted to wound healing and to immune homeostasis maintenance. In cancer, their physiological activities can be modulated, leading to an expansion of pro-inflammatory and immunosuppressive cells, the myeloid-derived suppressor cells (MDSCs), with detrimental consequences. The involvement of MDSCs in tumor development and progression has been widely investigated and MDSC-induced immunosuppression is acknowledged as a mechanism hindering effective immune checkpoint blockade. Small non-coding RNA molecules, the microRNAs (miRs), contribute to myeloid cell regulation at different levels, comprising metabolism and function, as well as their skewing to a MDSC phenotype. miR expression can be indirectly induced by cancer-derived factors or through direct miR import via extracellular vesicles. Due to their structural stability and their presence in body fluids miRs represent promising predictive biomarkers of resistance, as we recently found by investigating plasma samples of melanoma patients undergoing immune checkpoint blockade. Dissection of the miR-driven involved mechanisms would pave the way for the identification of new druggable targets. Here, we discuss the role of these miRs in shaping myeloid resistance to immunotherapy with a special focus on immunosuppression and immune escape.

Abstract CT198: Efficacy of metfOrmin in PrevenTIng glucocorticoid-induced diabetes in Melanoma, breAst or Lung Cancer patients with brain metastases: The phase II OPTIMAL study

Background: Brain metastases frequently occur in patients with late-stage cancers. Treatment with high-dose glucocorticoids (GCs) is usually started to prevent or reduce tumor-related edema and its deadly complications. However, treatment with high-dose GCs is associated with serious side effects, including diabetes and immunosuppression, which could promote tumor growth or reduce the effectiveness of antitumor therapies. Based on its potential antitumor properties and on its ability to prevent GC-induced diabetes, the antidiabetic compound Metformin could reduce short-term mortality in patients with brain metastases taking high-dose GCs. Methods: The OPTIMAL study is a monocentric, open label, randomized Phase II trial in patients with brain metastases from melanoma, lung or breast cancer, who require treatment with high-dose dexamethasone, as defined as a minimum of 8 mg daily based on the clinician judgment, for at least three consecutive weeks. At enrollment, patients are randomized in a 1:1 ratio to receive high-dose dexamethasone +/- metformin 2550 mg/day for 30 days. At randomization, patients are stratified according to: tumor origin, dose of dexamethasone (8-12 vs. &gt; 12 mg/day) and baseline fasting glycemia (&lt; 100 vs. 100-125 mg/dl). Patients may receive concomitant radiotherapy based on the judgment of the physician. The primary study endpoint is the rate of precocious (14 days) dexamethasone-induced diabetes, as defined as fasting plasma glucose levels ≥ 126 mg/dl. Discussion: The OPTIMAL study aims to evaluate the efficacy of upfront use of metformin in preventing the onset of GCs-induced diabetes and other metabolic perturbations in patients with brain metastases from melanoma, lung or breast cancer. Other clinical objectives consist in investigating the impact of metformin on precocious mortality, deterioration of ECOG PS and local (brain) disease control rate at one month after dexamethasone initiation. The effect of dexamethasone +/- metformin on other metabolites or growth factors, including amino acids, fatty acids, ketone bodies, IGF-1, as well as on the number, activation status and metabolism of peripheral blood immune cell populations will be evaluated as well. Trial registration: The OPTIMAL trial is registered at ClinicalTrials.gov (NCT04001725, June 28, 2019) and EudraCT (2019-000105-73, January 8, 2019).

Citation Format: Claudio Vernieri, Federico Nichetti, Francesca Ligorio, Emma Zattarin, Teresa Beninato, Riccardo Lobefaro, Giulia Bianchi, Giuseppe Capri, Marina Garassino, Giuseppe Lo Russo, Michele Del Vecchio, Paola Corsetto, Licia Rivoltini, Chiara Castelli, Filippo de Braud. Efficacy of metfOrmin in PrevenTIng glucocorticoid-induced diabetes in Melanoma, breAst or Lung Cancer patients with brain metastases: The phase II OPTIMAL study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT198.

Modulation of Pulmonary Microbiota by Antibiotic or Probiotic Aerosol Therapy: A Strategy to Promote Immunosurveillance against Lung Metastases

Pulmonary immunological tolerance to inhaled particulates might create a permissive milieu for lung metastasis. Lung microbiota contribute to pulmonary tolerance; here, we explored whether its manipulation via antibiotic or probiotic aerosolization favors immune response against melanoma metastasis. In lungs of vancomycin/neomycin-aerosolized mice, a decrease in bacterial load was associated with reduced regulatory T cells and enhanced T cell and NK cell activation that paralleled a significant reduction of melanoma B16 lung metastases. Reduction of metastases also occurred in lungs transplanted with bacterial isolates from antibiotic-treated lungs. Aerosolized Lactobacillus rhamnosus strongly promoted immunity against B16 lung metastases as well. Furthermore, probiotics or antibiotics improved chemotherapy activity against advanced B16 metastases. Thus, we identify a role for lung microbiota in metastasis and show that its targeting via aerosolization is a therapy that can prevent metastases and enhance responses to chemotherapy.

Immune microenvironment profiling of gastrointestinal stromal tumors (GIST) shows gene expression patterns associated to immune checkpoint inhibitors response

Few studies were conducted investigating the immunological profiles in gastrointestinal stromal tumors (GIST). Adaptive and innate immune cells are present in the tumor microenvironment, indicating GIST as inflamed tumors. In addition, murine models suggested a potential interaction between immune components and imatinib. In this retrospective study, the GIST immunological profile was investigated through in silico analysis and immunohistochemistry (IHC), exploring the basis for immunotherapy approaches. Gene expression profiles (GEP) from 31 KIT/PDGFRA-mutant GIST were analyzed to evaluate the tumor microenvironment and immunotherapy predictive signatures such as the expanded IFN-γ-induced immune signature (EIIS) and the T-cell-inflamed signature (TIS). GEP and IHC supported the presence of immune infiltrate in GIST, with dominance of CD4+ and CD8+ T cells and M2 macrophages showing a remarkable similarity with melanoma microenvironment. The EIIS genes were expressed in most of GIST samples and positively correlated with PD-L1 abundance (p < .0001). Co-expression was also found between PD-L1 and CD8A (p < .0001) or CD8B (p = .0003). Moreover, the median TIS score for GIST was between the 65th and 70th percentile of the Cancer Genome Atlas dataset, in the same range of tumors responding to anti-PD-1/PD-L1. Analysis of the Gene Expression Omnibus database GIST samples pre- and post-treatment confirmed that imatinib downregulates PD-L1 and IRF1 expression through the inhibition of KIT and PDGFRA, thus contributing to counteract the suppressed adaptive immune response against GIST. The presence of a rich immune infiltrate in GIST along with the presence of TIS and EIIS suggests that GIST may benefit from immunotherapy along with tyrosine kinase inhibitors.

Circulating mir-320a promotes immunosuppressive macrophages M2 phenotype associated with lung cancer risk

miRNAs play a central role in the complex signaling network of cancer cells with the tumor microenvironment. Little is known on the origin of circulating miRNAs and their relationship with the tumor microenvironment in lung cancer. Here, we focused on the cellular source and relative contribution of different cell types to circulating miRNAs composing our risk classifier of lung cancer using in vitro/in vivo models and clinical samples. A cell‐type specific expression pattern and topography of several miRNAs such as mir‐145 in fibroblasts, mir‐126 in endothelial cells, mir‐133a in skeletal muscle cells was observed in normal and lung cancer tissues. Granulocytes and platelets are the major contributors of miRNAs release in blood. miRNAs modulation observed in plasma of lung cancer subjects was consistent with de‐regulation of the same miRNAs observed during immunosuppressive conversion of immune cells. In particular, activated neutrophils showed a miRNA profile mirroring that observed in plasma of lung cancer subjects. Interestingly mir‐320a secreted by neutrophils of high‐risk heavy‐smokers promoted an M2‐like protumorigenic phenotype through downregulation of STAT4 when shuttled into macrophages. These findings suggest a multifactorial and nonepithelial cell‐autonomous origin of circulating miRNAs associated with risk of lung cancer and that circulating miRNAs may act in paracrine signaling with causative role in lung carcinogenesis and immunosuppression.

What's new?

microRNAs play a central role in the complex signaling network of cancer cells with the tumor microenvironment. However, little is known on the origin of circulating miRNAs and their mechanisms of action. This study found a multifactorial and non‐epithelial cell‐autonomous origin of circulating miRNAs associated with lung cancer risk. The findings also suggest a link between an immunosuppressive and pro‐tumorigenic microenvironment and modulation of circulating miRNAs associated with lung cancer risk. The authors propose a novel mechanism whereby miRNA released by neutrophils induce macrophage polarization to support lung cancer growth, highlighting the potential for reprogramming macrophages toward an anti‐tumor polarization.

Hepatocellular Carcinoma Is Associated With Gut Microbiota Profile and Inflammation in Nonalcoholic Fatty Liver Disease

The gut-liver axis plays a pivotal role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD), which is the third leading cause of hepatocellular carcinoma (HCC) worldwide. However, the link between gut microbiota and hepatocarcinogenesis remains to be clarified. The aim of this study was to explore what features of the gut microbiota are associated with HCC in patients with cirrhosis and NAFLD. A consecutive series of patients with NAFLD-related cirrhosis and HCC (group 1, 21 patients), NAFLD-related cirrhosis without HCC (group 2, 20 patients), and healthy controls (group 3, 20 patients) was studied for gut microbiota profile, intestinal permeability, inflammatory status, and circulating mononuclear cells. We finally constructed a model depicting the most relevant correlations among these features, possibly involved in hepatocarcinogenesis. Patients with HCC showed increased levels of fecal calprotectin, while intestinal permeability was similar to patients with cirrhosis but without HCC. Plasma levels of interleukin 8 (IL8), IL13, chemokine (C-C motif) ligand (CCL) 3, CCL4, and CCL5 were higher in the HCC group and associated with an activated status of circulating monocytes. The fecal microbiota of the whole group of patients with cirrhosis showed higher abundance of Enterobacteriaceae and Streptococcus and a reduction in Akkermansia. Bacteroides and Ruminococcaceae were increased in the HCC group, while Bifidobacterium was reduced. Akkermansia and Bifidobacterium were inversely correlated with calprotectin concentration, which in turn was associated with humoral and cellular inflammatory markers. A similar behavior was also observed for Bacteroides. Conclusion: Our results suggest that in patients with cirrhosis and NAFLD the gut microbiota profile and systemic inflammation are significantly correlated and can concur in the process of hepatocarcinogenesis.

Immunosuppressive circuits in tumor microenvironment and their influence on cancer treatment efficacy

It has been for long conceived that hallmarks of cancer were intrinsic genetic features driving tumor development, proliferation, and progression, and that targeting such cell-autonomous pathways could be sufficient to achieve therapeutic cancer control. Clinical ex vivo data demonstrated that treatment efficacy often relied on the contribution of host immune responses, hence introducing the concept of tumor microenvironment (TME), namely the existence, along with tumor cells, of non-tumor components that could significantly influence tumor growth and survival. Among the complex network of TME-driving forces, immunity plays a key role and the balance between antitumor and protumor immune responses is a major driver in contrasting or promoting cancer spreading. TME is usually a very immunosuppressed milieu because of a vast array of local alterations contrasting antitumor adaptive immunity, where metabolic changes contribute to cancer dissemination by impairing T cell infiltration and favoring the accrual and activation of regulatory cells. Subcellular structures known as extracellular vesicles then help spreading immunosuppression at systemic levels by distributing genetic and protein tumor repertoire in distant tissues. A major improvement in the knowledge of TME is now pointing the attention back to tumor cells; indeed, recent findings are showing how oncogenic pathways and specific mutations in tumor cells can actually dictate the nature and the function of immune infiltrate. As our information on the reciprocal interactions regulating TME increases, finding a strategy to interfere with TME crosstalk becomes more complex and challenging. Nevertheless, TME interactions represent a promising field for the discovery of novel biomarkers and therapeutic targets for improving treatment efficacy in cancer.

Immune landscape and in vivo immunogenicity of NY-ESO-1 tumor antigen in advanced neuroblastoma patients

BACKGROUND

Indirect evidence suggesting the immunosensitivity/immunogenicity of neuroblastoma is accumulating. The aims of this study were to investigate the immune landscape of neuroblastoma and to evaluate the in vivo immunogenicity of the NY-ESO-1 tumor antigen in advanced neuroblastoma patients.

METHODS

The immune infiltrating cells of the NY-ESO-1+ tumors from three HLA*A201 patients with metastatic neuroblastoma who relapsed after conventional treatments were evaluated by immunohistochemistry. The patients were vaccinated with the HLA-A*0201-restricted peptide NY-ESO-1_157-165(V). The peptide was emulsified in Montanide ISA51 and given subcutaneously in a phase I pilot study. The immunogenicity of NY-ESO-1 antigen was evaluated by monitoring mononuclear cells in patient peripheral blood, pre- and post-vaccine, by short-term in vitro sensitization, HLA-multimer staining and IFN-γ ELISpot analysis.

RESULTS

Both CD3 T cells and CD163 myeloid cells were present in pre-vaccine tumors and PD-1 and PD-L1 expression was mainly found in the immune infiltrate. Despite the advanced stage of the disease, the vaccination induced systemic NY-ESO-1 specific CD8 T cells releasing IFN-γ in response to activation with the NY-ESO-1 peptide and an HLA-A2 positive neuroblastoma cell line.

CONCLUSIONS

Our results indicate that vaccination with a tumor-associated peptide is able to boost NY-ESO-1-specific, functionally active T cells in advanced neuroblastoma patients with lymphocyte infiltration in their pre-vaccine tumors.

TRIAL REGISTRATION

EudraCT #2006-002859-33.

Abstract 3517: Targeting pH regulators to modulate human hepatocellular carcinoma microenvironment

Hepatocellular carcinoma (HCC) arises in a hypoxic/acidic microenvironment in which the pO2 is about 0.8%. This condition favors tumor progression and fosters immunosuppression. Tumor cells survive this obstile environment by overexpressing pH regulators such as carbonic anhydrase (CA) IX, XII and V-ATPase complex. We investigated the expression and functional properties of these molecules in HCC cell lines and patients, to evaluate their potential role as novel therapeutic agents against HCC. The expression of CAs and V-ATPase subunits was assayed by qRT-PCR, western blot and confocal microscopy in HCC cell lines exposed to normoxia (21% O2) or hypoxia (1% O2). The effect of pH regulatory inhibitors on HCC cell viability was evaluated by MTT assay. Paired tumoral and non-tumoral liver tissues (n=57) from HCC patients were analyzed for the expression of pH regulatory molecules by qRT-PCR and by immunohistochemistry. Multi-paramentric flow cytometry analysis was performed on patient-derived HCC cell suspensions exposed to V-ATPase inhibitor or vehicle for 24h (n=6). Human HCC tissue explants (n=8) were cultured in presence of V-ATPase inhibitor for 24h and gene expression was analysed by qRT-PCR. CAs and V-ATPase are expressed by HCC cell lines grown under normoxia (21% O2) and a selective increment of CAIX and CAXII was observed after hypoxia (1% O2) exposure. These molecules were involved in cancer cell survival, as demonstrated by the significant reduction of tumor viability by CAIX and V-ATPase inhibitors. Ex vivo analyses showed a focal and intense plasma membrane immunoreactivity for CAIX in discrete nests of hepatocytes inside HCC lesions and in cholangiocytes within normal and non-tumoral tissues. Tumor cells selectively expressed CAXII in the cytoplasm. In vivo and ex vivo we observed that in the hypoxic microenvironment of HCC CAXII was retained in the endoplasmic reticulum of hepatocytes. Significant, albeit heterogeneous, positivity for V-ATPase was detected in most of HCC lesions analyzed. Importantly, infiltrating immune cells compatible with M2 macrophage phenotype expressed the V-ATPase. The inhibiton of V-ATPase by omeprazole in cell suspensions obtained from clinical HCC tissues showed a decreased production of CCL22 paralleled by an increment of IFNγ by M2 macrophages. Short-term treatment of HCC tissue explants with omeprazole exerted important effects on tumor microenvironment reducing the immunosuppressive gene CCL22 together incrementing IFNG, but also affected the aggressiveness of tumoral cells inducing a down-modulation of epithelial to mesenchymal transition associated genes VIM and MYC and increasing the transcription of CDH1. In conclusion our data indicate that pH regulators, overexpressed in tumor and immune cells composing the HCC microenvironment, play a role in maintaining an aggressive and immunosuppressive milieu in HCC and likely they represent a promising target.

Citation Format: Alessandra Tuccitto, Olga Kuchuk, Davide Citterio, Veronica Huber, Chiara Camisaschi, Massimo Milione, Barbara Vergani, Antonello Villa, Licia Rivoltini, Chiara Castelli, Vincenzo Mazzaferro. Targeting pH regulators to modulate human hepatocellular carcinoma microenvironment [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 3517.

Abstract 4981: Circulating mir-320 promotes immunosuppressive macrophages M2 phenotype associated with lung cancer progression

INTRODUCTION miRNAs play a role in the complex network of signaling between cancer cells and tumor microenvironment. We previously reported the identification of diagnostic miRNA signatures (MSC) based on 24-miRNAs in plasma samples of lung cancer patients detected by low dose computed tomography (LDCT) screening.

MATERIAL and METHODS To evaluate the potential origin of the miRNAs of the diagnostic signature, we analyzed their expression by real-time or digital PCR in both cells and conditioned medium (CM) from different cell types of the lung microenvironment as well as in plasma samples of heavy smokers and patients. Lung tissues and cell-blocks were analyzed by miRNAs in situ hybridization. Modulation of miRNAs after in vitro treatments, known to induce changes associated with cancer progression, in different cell types was assessed and correlated to changes observed in circulating miRNAs signatures.

RESULTS and DISCUSSION The analysis of 100 pre and post surgery plasma samples from 31 patients suggested a tumor-related origin of those miRNAs which significantly declined to basal levels after curative tumor resection. Other miRNAs (miR-126, miR-92a, miR-320, miR-28-3p, miR-486, miR-451, miR-16) remained deregulated afer surgery likely indicating a “host-related” origin and the persistence of a risk profile. Specific expression of mir-145 in fibroblasts, mir-126 in endothelial cells, mir-133 in skeletal muscle cells, mir-451 and 142-3p in hematopoietic cells was observed with a good degree of correlation between cellular and secreted miRNAs levels in each cell types (Pearson correlation range: 0.59-0.81). In vitro experiments comparing activated vs. resting neutrophils, showed that 17 out of the 24 miRNAs were concordantly modulated as in lung cancer patients' plasma (Pearson r=0.60, p&lt;0.01), indicating a role of activated neutrophils in determining plasma miRNAs profile associated with lung cancer . Interestingly, we found increased miR-320 levels in cells and CM of neutrophils isolated from MSC positive compared to MSC negative subjects (fold increase: 1.7 and 2.4, respectively, p&lt;0.05). Treatment of cultured macrophages with CM of neutrophils resulted in higher levels of the mature form of miR-320 but not of its pri-miRNA expression levels. Exogenous miR-320 induced M2 polarization, as assessed by the increase of IL-10 expression and of CD163 and CD68 positive cells. These effects of mir-320 were abolished when anti-mir-320 was transfected in recipient cells. Mir-320 over-expressing macrophages were able to stimulate cancer growth both in vitro and in vivo models. Furthermore, we demonstrated that STAT4 was a direct target of miR-320 and responsible of the M2-like switch.

CONCLUSION These findings suggest that circulating miRNAs are non cell-autonomous, may act in paracrine signalling and have a causative role in lung carcinogenesis and immunesuppression.

Citation Format: Orazio Fortunato, Cristina Borzi, Massimo Milione, Giovanni Centonze, Davide Conte, Mattia Boeri, Massimo Moro, Federica Facchinetti, Luca Roz, Veronica Huber, Chiara Camisaschi, Chiara Castelli, Licia Rivoltini, Valeria Cancila, Claudio Tripodo, Ugo Pastorino, Gabriella Sozzi. Circulating mir-320 promotes immunosuppressive macrophages M2 phenotype associated with lung cancer progression [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 4981.

Loss of Heterozygosity of Dq Alpha Gene in Human Malignant Melanoma

DNAs from human melanoma cells, used at early in vitro passage, were evaluated by Southern blot analysis for somatic loss of heterozygosity at the DQ alpha gene. A total of 7 melanomas, 3 primary and 4 metastatic derived from 5 different patients were studied; in one case (pt 665) cell lines were derived from two anatomically different subcutaneous metastasis, whereas in a second case (pt 9923) both the primary tumor and a lymph node metastasis were available. Restriction length polymorphism (RFLP) analysis, performed on autologous peripheral blood lymphocyte (PBL) DNA digested with different enzymes, showed a pattern of bands compatible with the constitutional heterozygous typing at DQ alpha gene in 4 cases whereas 1 case revealed an homozygous typing. When melanoma DNAs were analysed, 1 out of the 4 informative cases (pt 1007) showed a loss of a diagnostic fragment for DQ alpha gene when digested with both Taq I and Bgl I enzymes. These results indicate that class II allelic losses detectable by RFLP can be found on malignant melanoma and add further complexity on the involvement of chromosome 6 whose cytogenetic abnormality are the most consistent in this human neoplasia.

pH regulators to target the tumor immune microenvironment in human hepatocellular carcinoma

Interfering with tumor metabolism is an emerging strategy for treating cancers that are resistant to standard therapies. Featuring a rapid proliferation rate and exacerbated glycolysis, hepatocellular carcinoma (HCC) creates a highly hypoxic microenvironment with excessive production of lactic and carbonic acids. These metabolic conditions promote disease aggressiveness and cancer-related immunosuppression. The pH regulatory molecules work as a bridge between tumor cells and their surrounding milieu. Herein, we show that the pH regulatory molecules CAIX, CAXII and V-ATPase are overexpressed in the HCC microenvironment and that interfering with their pathways exerts antitumor activity. Importantly, the V-ATPase complex was expressed by M2-like tumor-associated macrophages. Blocking ex vivo V-ATPase activity established a less immune-suppressive tumor microenvironment and reversed the mesenchymal features of HCC. Thus, targeting the unique cross-talk between tumor cells and the tumor microenvironment played by pH regulatory molecules holds promise as a strategy to control HCC progression and to reduce the immunosuppressive pressure mediated by the hypoxic/acidic metabolism, particularly considering the potential combination of this strategy with emerging immune checkpoint-based immunotherapies.

Sunitinib-induced morpho-functional changes and drug effectiveness in malignant solitary fibrous tumours

Sunitinib improves the outcomes of patients with solitary fibrous tumours (SFTs). The aim of this study was to investigate and contextualise sunitinib-induced morpho-functional changes in order to gain insights into the drug's mechanism of action.To this end, four surgical specimens obtained from two sunitinib-responsive patients with malignant SFT, and one primary cell culture obtained from fresh tumoral tissue and its stabilised cell line, were studied by means of immunohistochemistry, bright field in situ hybridisation, immunofluorescence/confocal microscopy, and biochemistry.The post-sunitinib surgical samples were characterised by two biologically relevant morpho-functional changes: clear areas and necrotic foci. The first were associated with the attenuation/loss of PDGFRB expression and decreased mTOR signalling, and corresponded to a pathological response. The second were associated with the over-expression of PDGFRB and VEGFA, strong mTOR signalling activation, and the appearance of HIF1α expression, hallmarks of pathological progression. The analysis clearly showed that sunitinib reduces the vascular supply network and inhibits tumoral cells. It also either induces autophagy, thus favouring drug response, or impairs autophagy as a result of lysosome sequestration, thus favouring disease progression. These distinct autophagic events were associated with different myeloid immune contextures. Finally, we also found that PDGFRB is one of the components of a complex that includes Beclin 1 and VPS34.The results of these tissue-based analyses provide new insights into sunitinib's mechanism of action in SFT patients.

Association of immune contexture, age, and tumor stage in peripheral neuroblastic tumors (PNT)

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Background: PNTs, a family of tumors arising in the embryonal remnants of the sympathetic nervous system, account for 7-10% of all tumors in children. NMYC status, stage, and age are the most important prognostic factors. The association of patient age and prognosis could be influenced by the maturity of immune system. The aims of this study were to describe the immune contexture in PNTs and to investigate its relationships with patient age and tumor stage. Methods: A cohort of 45 consecutive children with PNT diagnosed and treated at a single centre (2008-2014) with available primary tumor specimen at disease diagnosis and no prior chemotherapy was investigated. Immunohistochemistry for CD45, CD3, CD20, CD14, CD163, CD68, PDL1(P142), and FOXP3 was performed. Presence and status of immune infiltration were scored as follow: the presence of aggregates was assessed at 2.5X scanning magnification and recorded as "high" if present or "low" if no aggregates were visible. Patient age was categorized according to London WB et al (2005) using a 460 days cut-off and INSS tumor stage was considered. Results: Patient age ranged between 8 days and 14 years. Tumor infiltrating CD45 and CD3 scores were lower in INSS tumor stage 4 compared to other INSS tumor stages (CD45: OR=12.37, 95%CI 1.38 -171.00, P=0.01; CD3: OR=9.86, 95%CI 1.52-114.13; P<0.01). Similarly, the monocytes and macrophages markers CD163 and CD14 were associated with tumor INSS stage. The expression of these markers was significantly higher in patient older than 460 days (CD163: OR=4.41, 95%CI 0.77-32.12, P=0.03; CD14: OR=6.94, 95%CI 0.79-335.33, P<0.01). Interestingly, PD-L1 was detected only on immune cells but not on neuroblastic cells. Finally, Treg(FOXP3+) score was low in all but one case. Conclusions: Immune contexture in PNT significantly varies across patient age and tumor stage suggesting a role for maturity of immune system in these patients. [Table: see text]

microRNA Expression in Sentinel Nodes from Progressing Melanoma Patients Identifies Networks Associated with Dysfunctional Immune Response

Sentinel node biopsy (SNB) is a main staging biomarker in melanoma and is the first lymph node to drain the tumor, thus representing the immunological site where anti-tumor immune dysfunction is established and where potential prognostic immune markers can be identified. Here we analyzed microRNA (miR) profiles in archival tumor-positive SNBs derived from melanoma patients with different outcomes and performed an integrated analysis of transcriptional data to identify deregulated immune signaling networks. Twenty-six miRs were differentially expressed in melanoma-positive SNB samples between patients with disease progression and non-progressing patients, the majority being previously reported in the regulation of immune responses. A significant variation in miR expression levels was confirmed in an independent set of SNB samples. Integrated information from genome-wide transcriptional profiles and in vitro assessment in immune cells led to the identification of miRs associated with the regulation of the TNF receptor superfamily member 8 (TNFRSF8) gene encoding the CD30 receptor, a marker increased in lymphocytes of melanoma patients with progressive disease. These findings indicate that miRs are involved in the regulation of pathways leading to immune dysfunction in the sentinel node and may provide valuable markers for developing prognostic molecular signatures for the identification of stage III melanoma patients at risk of recurrence.

Targeting Immune Regulatory Networks to Counteract Immune Suppression in Cancer

The onset of cancer is unavoidably accompanied by suppression of antitumor immunity. This occurs through mechanisms ranging from the progressive accumulation of regulatory immune cells associated with chronic immune stimulation and inflammation, to the expression of immunosuppressive molecules. Some of them are being successfully exploited as therapeutic targets, with impressive clinical results achieved in patients, as in the case of immune checkpoint inhibitors. To limit immune attack, tumor cells exploit specific pathways to render the tumor microenvironment hostile for antitumor effector cells. Local acidification might, in fact, anergize activated T cells and facilitate the accumulation of immune suppressive cells. Moreover, the release of extracellular vesicles by tumor cells can condition distant immune sites contributing to the onset of systemic immune suppression. Understanding which mechanisms may be prevalent in specific cancers or disease stages, and identifying possible strategies to counterbalance would majorly contribute to improving clinical efficacy of cancer immunotherapy. Here, we intend to highlight these mechanisms, how they could be targeted and the tools that might be available in the near future to achieve this goal.

Immunomodulatory Factors Control the Fate of Melanoma Tumor Initiating Cells

Melanoma is a highly heterogeneous tumor for which recent evidence supports a model of dynamic stemness. Melanoma cells might temporally acquire tumor-initiating properties or switch from a status of tumor-initiating cells (TICs) to a more differentiated one depending on the tumor context. However, factors driving these functional changes are still unknown. We focused on the role of cyto/chemokines in shaping TICs isolated directly from tumor specimens of two melanoma patients, namely Me14346S and Me15888S. We analyzed the secretion profile of TICs and of their corresponding melanoma differentiated cells and we tested the ability of cyto/chemokines to influence TIC self-renewal and differentiation. We found that TICs, grown in vitro as melanospheres, had a complex secretory profile as compared to their differentiated counterparts. Some factors, such as CCL-2 and IL-8, also produced by adherent melanoma cells and melanocytes did not influence TIC properties. Conversely, IL-6, released by differentiated cells, reduced TIC self-renewal and induced TIC differentiation while IL-10, produced by Me15888S, strongly promoted TIC self-renewal through paracrine/autocrine actions. Complete neutralization of IL-10 activity by gene silencing and antibody-mediated blocking of the IL-10Rα was required to sensitize Me15888S to IL-6-induced differentiation. For the first time these results show that functional heterogeneity of melanoma could be directly influenced by inflammatory and suppressive soluble factors, with IL-6 favoring TIC differentiation, and IL-10 supporting TIC self-renewal. Thus, understanding the tumor microenvironment (TME) role in modulating melanoma TIC phenotype is fundamental to identifying novel therapeutic targets to achieve long-lasting regression of metastatic melanoma. Stem Cells 2016;34:2449-2460.

Density heterogeneity and fluid-blood levels in patients aged over 55 with lobar hematoma

BACKGROUND

Density heterogeneity and fluid-blood levels (FBLs) are frequently seen on acute CT scans of deep brain hemorrhage. Our aim was to analyze the density heterogeneity and FBLs seen on acute/subacute CT in patients aged>55 with lobar haemorrhage (LH), and to study the relationship of these brain abnormalities with other parameters, including cerebral amyloid angiopathy (CAA)-related abnormalities.

METHODS

This was an observational study and retrospective analysis of early CT scans (<7 days) in patients aged>55 years with acute lobar hemorrhage who, between 2012 and 2015, were entered into our stroke database. A total of 37 LH episodes (without trauma, abnormal coagulation/platelet counts, vascular malformation, tumor or vasculitis) in 35 patients were analyzed. Other studied parameters were gender, age, history of hypertension, blood pressure on admission, prior antiplatelet treatment, aPTT, PTT, platelet count, hematocrit, timing of first CT, LH volume, involved lobe, cortical superficial siderosis, microbleeds, chronic LH and CAA (classic and modified Boston) criteria. CAA-related abnormalities seen on MRI were also scored.

RESULTS

Overall, in 26 LH episodes (70%), CT was performed within 24h. Density heterogeneity and FBLs were seen in 19 (51%) and 9 (24%) LH episodes, respectively. Also, according to classic and modified Boston criteria, 18 (51%) and 24 (69%) patients, respectively, fulfilled criteria for probable/definite CAA. As for the presence of FBLs, a statistically significant association was found with both the presence of probable/definite CAA according to modified Boston criteria (P=0.033) and the presence of superficial siderosis (P=0.019).

CONCLUSION

Density heterogeneity and, to a lesser degree, FBLs are frequently seen in patients aged>55 with LH. FBLs may also be associated with CAA-related hemorrhage.

Evolution of Dermatofibrosarcoma Protuberans to DFSP-Derived Fibrosarcoma: An Event Marked by Epithelial-Mesenchymal Transition-like Process and 22q Loss

Dermatofibrosarcoma protuberans (DFSP) is a rare and indolent cutaneous sarcoma. At times, a fibrosarcomatous transformation marked by a more aggressive clinical behavior may be present. We investigated the natural history and the molecular bases of progression from classic DFSP to the fibrosarcomatous form (FS-DFSP), looking, retrospectively, at the outcome of all patients affected by primary DFSP treated at our institution from 1993 to 2012 and analyzing the molecular profile of 5 DFSPs and 5 FS-DFSPs by an integrated genomics approach (whole transcriptome sequencing, copy number analysis, FISH, qRT-PCR, IHC). The presence of fibrosarcomatous features was identified in 20 (7.6%) patients out of 263 DFSP. All cases were treated with macroscopic complete surgery. A local relapse occurred in 4 of 23 patients who received a microscopic marginal surgery (2 classic DFSP, 2 FS-DFSP), while metastasis affected 2 patients, both FS-DFSP (10% of FS-DFSP), being the first event. DFSP evolution to FS-DFSP was paralleled by a transcriptional reprogramming. The recurrent loss of chromosome 22q appeared to contribute to this phenomenon by promoting the expression of epigenetic regulators, such as EZH2. Loss of the p16/CDKN2A/INK4A locus at 9p was also observed in two FS-DFSP metastatic cases.

IMPLICATIONS

FS-DFSP is a rare subgroup among DFSP, with a 10% metastatic risk, that was independent from local recurrence and that was not observed in DFSP, that were all cured by wide surgery. Chromosome 22q deletion might play a role in FS-DFSP, and p16 loss may convey a poor outcome. EZH2 dysregulation was also found and represents a druggable target. Mol Cancer Res; 14(9); 820-9. ©2016 AACR.

Efficacy and Biological Activity of Imatinib in Metastatic Dermatofibrosarcoma Protuberans (DFSP)

PURPOSE

To report on imatinib mesylate (IM) in patients with metastatic dermatofibrosarcoma protuberans (DFSP)/fibrosarcomatous (FS)-DFSP and on the impact of the treatment on tumor biology.

EXPERIMENTAL DESIGN

Ten consecutive patients treated with IM from 2007 to 2015 for a metastatic relapse from DFSP/FS-DFSP were identified. FISH analysis for COL1A1-PDGFB was performed. Two IM-treated and 4 naïve FS-DFSP were transcriptionally profiled by RNAseq on HiScanSQ platform. Differential gene expression was analyzed with edgeR (Bioconductor), followed by hierarchical clustering and Principal Component Analysis.

RESULTS

All cases featured fibrosarcomatous in the metastasis and retained the COL1A1-PDGFB. Best RECIST response was: 8 partial response, 1 stable disease, and 1 progressive disease. Median progression-free survival was 11 months. Five patients received surgery after IM and all relapsed. IM was restored in 4 patients with a new response. After IM, the most upregulated genes included those encoding for immunoglobulins and those affecting functions and differentiation of endothelial cells. Pathway enrichment analysis revealed upregulation in genes involved in antigen processing and presentation, natural killer-mediated cytotoxicity, and drug and xenobiotics metabolism. Conversely, a significant down-regulation of kinase signaling pathways was detected.

CONCLUSIONS

All metastatic cases were fibrosarcomatous. Most patients responded to IM, but PFS was shorter than reported in published series which included both DFSP and FS-DFSP. All patients operated after IM had a relapse, suggesting that IM cannot eradicate metastatic cases and that the role of surgery is limited. Transcriptional profile of naïve and posttreatment samples pointed the contribution of immune infiltrates in sustaining the response to IM.

Consensus nomenclature for CD8+ T cell phenotypes in cancer

Whereas preclinical investigations and clinical studies have established that CD8⁺ T cells can profoundly affect cancer progression, the underlying mechanisms are still elusive. Challenging the prevalent view that the beneficial effect of CD8⁺ T cells in cancer is solely attributable to their cytotoxic activity, several reports have indicated that the ability of CD8⁺ T cells to promote tumor regression is dependent on their cytokine secretion profile and their ability to self-renew. Evidence has also shown that the tumor microenvironment can disarm CD8⁺ T cell immunity, leading to the emergence of dysfunctional CD8⁺ T cells. The existence of different types of CD8⁺ T cells in cancer calls for a more precise definition of the CD8⁺ T cell immune phenotypes in cancer and the abandonment of the generic terms "pro-tumor" and "antitumor." Based on recent studies investigating the functions of CD8⁺ T cells in cancer, we here propose some guidelines to precisely define the functional states of CD8⁺ T cells in cancer.

Melan-A/MART-1 immunity in a EWS-ATF1 translocated clear cell sarcoma patient treated with sunitinib: a case report

Background

Clear cell sarcoma (CCS), initially named malignant melanoma of soft parts, is an aggressive soft tissue sarcoma (STS) that, due to MITF activation, shares with melanoma the expression of melanocyte differentiation antigens. CCS is poorly sensitive to chemotherapy. Multi-kinase inhibitors have been used as therapeutic agents. In the case we report here, treatment with sunitinib induced a long-lasting clinical response that was associated with an immune activation directed against Melan-A/MART-1 antigen.

Case presentation

A 28 years old female patient with an advanced molecularly confirmed CCS resistant to conventional chemotherapy was started in January 2012 on sunitinib, 37.5 mg/day, with evidence of radiologic and metabolic response at the primary and metastatic sites of disease. Pathologic response and loss of the Melan-A/MART-1 antigen were evidenced on residual tumor removed in April 2012. Immunological monitoring performed on patient’s blood during pharmacological treatment revealed a systemic, Melan-A/MART-1 specific immunity and a low frequency of immunosuppressive cells. Sunitinib was restarted in May 2012, with a new response, and continued for 11 months although with repeatedly interruptions due to toxicity. Disease progression and new responses were documented at each treatment interruption and restart. Sunitinib was definitively interrupted in April 2013 for disease progression.

Conclusion

The analysis of this case proves that antigens expressed by CCS, as for melanoma, can be immunogenic in vivo and that tumor-antigen specific T cells may exert anti-tumor activity in CCS patient. Thus, manipulation of the immune response may have therapeutic potential for this STS subtype and immunotherapy approaches, can be promising therapeutic options for these patients.

Modulation of the myeloid compartment of the immune system by angiogenic- and kinase inhibitor-targeted anti-cancer therapies

Targeted therapies were rationally designed to inhibit molecular pathways in tumor cells critically involved in growth and survival; however, many drugs used in targeted therapies may affect the immune system. In addition, selected conventional chemotherapeutic agents have also been reported to be endowed with direct or indirect effects on immunity, for instance via immunogenic death of tumors. Thus, cancer therapies may have off-target effects, some of which are directed to the immune system. Here, we will review some of these effects in specific therapeutic approaches. We will examine the modulation of the immune contexture in human sarcoma and melanoma induced by anti-angiogenic therapies and by BRAF inhibitors, respectively. We will then discuss how the anti-tumor agent trabectedin is selectively cytotoxic to cells of the monocytic-macrophage lineage and how these immune-related effects can be part of the response to treatment.