Single-cell multiomics profiling reveals heterogeneous transcriptional programs and microenvironment in DSRCTs.

Desmoplastic small round cell tumor (DSRCT) is a rare, aggressive sarcoma driven by the EWSR1::WT1 chimeric transcription factor. Despite this unique oncogenic driver, DSRCT displays a polyphenotypic differentiation of unknown causality. Using single-cell multi-omics on 12 samples from five patients, we find that DSRCT tumor cells cluster into consistent subpopulations with partially overlapping lineage- and metabolism-related transcriptional programs. In vitro modeling shows that high EWSR1::WT1 DNA-binding activity associates with most lineage-related states, in contrast to glycolytic and profibrotic states. Single-cell chromatin accessibility analysis suggests that EWSR1::WT1 binding site variability may drive distinct lineage-related transcriptional programs, supporting some level of cell-intrinsic plasticity. Spatial transcriptomics reveals that glycolytic and profibrotic states specifically localize within hypoxic niches at the periphery of tumor cell islets, suggesting an additional role of tumor cell-extrinsic microenvironmental cues. We finally identify a single-cell transcriptomics-derived epithelial signature associated with improved patient survival, highlighting the clinical relevance of our findings.

A Comprehensive Review on the Role of Lurbinectedin in Soft Tissue Sarcomas.

OPINION STATEMENT: Soft tissue sarcoma (STS), a substantial group of aggressive and rare tumors with tissue heterogeneity, is infrequently represented in clinical trials with an urgent necessity for newer treatment options. Lurbinectedin, an analog of trabectedin, is currently approved, in various countries, as a single agent, for the treatment of patients with relapsed small cell lung cancer (SCLC). However, preclinical and phase I and phase II trials have demonstrated the efficacy of lurbinectedin in different tumor types, including STS. The better understanding of the pathophysiology and evolution of STS as well as the mechanism of action of lurbinectedin in addition to the available data regarding the activity of this drug in this subset of patients will pave the way to newer therapeutic options and strategies.

Antibody drug conjugates in older patients: State of the art.

More than half of cancer cases occur in patients aged 65 years or older. The efficacy and safety of antibody drug conjugates (ADCs) in older patients remains an unclear subject as available evidence is limited. Geriatric population is underrepresented in clinical trials. Consequently, most of our knowledge regarding innovative therapeutics was studied on a younger population. In this review of published literature, we report the available information on efficacy, safety and pharmacokinetics of FDA approved ADCs for hematologic malignancies and solid tumors in the geriatric population. We explore the results of clinical trials dedicated for older individuals as well as subgroup analyses of the geriatric population in major trials evaluating these drugs. Available data suggest a similar efficacy in older adults as compared to general population. However, older patients might be prone to a higher rate of adverse events in incidence with a potential impact on quality of life. We lack data to support primary dose reductions or schedule modifications in this category of patients. No pharmacokinetic differences were reported between age groups. It is crucial to encourage the development of clinical trials dedicated to older patients with geriatric parameters (G8 score, G-CODE…) so that results can be more representative of this population outside of clinical trials.

Desmoid-type fibromatosis: Current therapeutic strategies and future perspectives.

Desmoid tumors (DT) are rare, slow-growing, locally invasive soft tissue tumors that often pose significant therapeutic challenges. Traditional management strategies including active surveillance, surgery, radiotherapy, and systemic therapy which are associated with varying recurrence rates and high morbidity. Given the challenging nature of DT and the modest outcomes associated with current treatment strategies, there has been a growing interest in the field of γ-secretase inhibitors as a result of its action on the Wnt/ß-catenin signaling pathway. In this review article, we will shed the light on the pathogenesis and molecular biology of DT, discuss its symptoms and diagnosis, and provide a comprehensive review of the traditional therapeutic approaches. We will also delve into the mechanisms of action of γ-secretase inhibitors, its efficacy, and the existing preclinical and clinical data available to date on the use of these agents, as well as the potential challenges and future prospects in the treatment landscape of these tumors.

Systemic Therapy in Advanced Pleomorphic Liposarcoma: a Comprehensive Review.

OPINION STATEMENT: The therapeutic approach of pleomorphic liposarcoma (PLPS), a rare high-grade subgroup of soft tissue sarcoma, is commonly extrapolated from the management of other LPS subtypes. Only published retrospective data on PLPS currently serve as a guide for oncologists without clear recommendations or specific guidelines. In the advanced setting, specific systemic therapy such as eribulin and trabectedin showed promising activity in comparison to conventional therapy (doxorubicin- and gemcitabine-based protocols), which currently remains the current standard of care at initial stages of the disease. The better understanding of soft tissue sarcoma (STS) pathophysiology and disease course has led to the development of adapted clinical trial designs for rare STS histotypes with specific treatment approach.

Evolution of Patterns of Care and Outcomes in the Real-Life Setting for Patients with Metastatic GIST Treated in Three French Expert Centers over Three Decades.

Gastrointestinal stromal tumors (GIST) are rare mesenchymal tumors characterized by KIT or PDGFRA mutations. Over three decades, significant changes in drug discovery and loco-regional (LR) procedures have impacted treatment strategies. We assessed the evolution of treatment strategies for metastatic GIST patients treated in the three national coordinating centers of NetSarc, the French network of sarcoma referral centers endorsed by the National Institute of Cancers, from 1990 to 2018. The primary objective was to describe the clinical and biological profiles as well as the treatment modalities of patients with metastatic GIST in a real-life setting, including access to clinical trials and LR procedures in the metastatic setting. Secondary objectives were to assess (1) patients' outcome in terms of time to next treatment (TNT) for each line of systemic treatment, (2) patients' overall survival (OS), (3) evolution of patients' treatment modalities and OS according to treatment access: <2002 (pre-imatinib approval), 2002-2006 (pre-sunitinib approval), 2006-2014 (pre-regorafenib approval), post 2014, and (4) the impact of clinical trials and LR procedures on TNT and OS in the metastatic setting. 1038 patients with a diagnosis of GIST made in one of the three participating centers between 1990 and 2018 were included in the national prospective database. Among them, 492 patients presented metastasis, either synchronous or metachronous. The median number of therapy lines in the metastatic setting was 3 (range 0-15). More than half of the patients (55%) participated in a clinical trial during the course of their metastatic disease and half (51%) underwent additional LR procedures on metastatic sites. The median OS in the metastatic setting was 83.4 months (95%CI [72.7; 97.9]). The median TNT was 26.7 months (95%CI [23.4; 32.3]) in first-line, 10.2 months (95%CI [8.6; 11.8]) in second line, 6.7 months (95%CI [5.3; 8.5]) in third line, and 5.5 months (95%CI [4.3; 6.7]) in fourth line, respectively. There was no statistical difference in OS in the metastatic setting between the four therapeutic periods (log rank, p = 0.18). In multivariate analysis, age, AFIP Miettinen classification, mutational status, surgery of the primary tumor, participation in a clinical trial in the first line and LR procedure to metastatic sites were associated with longer TNT in the first line, whereas age, mitotic index, mutational status, surgery of the primary tumor and LR procedure to metastatic sites were associated with longer OS. This real-life study advocates for early reference of metastatic GIST patients to expert centers to orchestrate the best access to future innovative clinical trials together with LR strategies and further improve GIST patients' survival.

Fibroblasts generate topographical cues that steer cancer cell migration.

Fibroblasts play a fundamental role in tumor development. Among other functions, they regulate cancer cells' migration through rearranging the extracellular matrix, secreting soluble factors, and establishing direct physical contacts with cancer cells. Here, we report that migrating fibroblasts deposit on the substrate a network of tubular structures that serves as a guidance cue for cancer cell migration. Such membranous tubular network, hereafter called tracks, is stably anchored to the substrate in a ß5-integrin-dependent manner. We found that cancer cells specifically adhere to tracks by using clathrin-coated structures that pinch and engulf tracks. Tracks thus represent a spatial memory of fibroblast migration paths that is read and erased by cancer cells directionally migrating along them. We propose that fibroblast tracks represent a topography-based intercellular communication system capable of steering cancer cell migration.

Single-agent gemcitabine in patients with advanced, pre-treated angiosarcoma: A multicenter, retrospective study.

Gemcitabine has shown clinical activity against angiosarcoma in small series, alone, or combined with taxanes. We aimed to evaluate its activity as a single-agent in a larger series of patients with advanced angiosarcoma. We retrospectively reviewed the electronic medical records of consecutive adult patients with advanced angiosarcoma treated with single-agent gemcitabine at our institutions from January 2010 to January 2021. Response was evaluated according to RECIST 1.1, and toxicity was graded according to NCI-CTC v5.0. 42 patients were identified. 38 patients (90%) had received prior anthracyclines and weekly paclitaxel, and 9 (21%) had received pazopanib. The best tumor response was partial response (PR) in 16 patients (38%), or stable disease (10 patients, 24%). All 8 patients with cardiac angiosarcoma experienced a PR. Median PFS was 5.4 months (95%CI: 3.1-6.5), and median OS was 9.9 months (95%CI: 6.6-13.4). Single-agent gemcitabine has clinically meaningful activity in advanced, heavily pre-treated angiosarcoma.

Oncogenic chimeric transcription factors drive tumor-specific transcription, processing, and translation of silent genomic regions.

Many cancers are characterized by gene fusions encoding oncogenic chimeric transcription factors (TFs) such as EWS::FLI1 in Ewing sarcoma (EwS). Here, we find that EWS::FLI1 induces the robust expression of a specific set of novel spliced and polyadenylated transcripts within otherwise transcriptionally silent regions of the genome. These neogenes (NGs) are virtually undetectable in large collections of normal tissues or non-EwS tumors and can be silenced by CRISPR interference at regulatory EWS::FLI1-bound microsatellites. Ribosome profiling and proteomics further show that some NGs are translated into highly EwS-specific peptides. More generally, we show that hundreds of NGs can be detected in diverse cancers characterized by chimeric TFs. Altogether, this study identifies the transcription, processing, and translation of novel, specific, highly expressed multi-exonic transcripts from otherwise silent regions of the genome as a new activity of aberrant TFs in cancer.

PBRM1 Deficiency Confers Synthetic Lethality to DNA Repair Inhibitors in Cancer.

Inactivation of Polybromo 1 (PBRM1), a specific subunit of the PBAF chromatin remodeling complex, occurs frequently in cancer, including 40% of clear cell renal cell carcinomas (ccRCC). To identify novel therapeutic approaches to targeting PBRM1-defective cancers, we used a series of orthogonal functional genomic screens that identified PARP and ATR inhibitors as being synthetic lethal with PBRM1 deficiency. The PBRM1/PARP inhibitor synthetic lethality was recapitulated using several clinical PARP inhibitors in a series of in vitro model systems and in vivo in a xenograft model of ccRCC. In the absence of exogenous DNA damage, PBRM1-defective cells exhibited elevated levels of replication stress, micronuclei, and R-loops. PARP inhibitor exposure exacerbated these phenotypes. Quantitative mass spectrometry revealed that multiple R-loop processing factors were downregulated in PBRM1-defective tumor cells. Exogenous expression of the R-loop resolution enzyme RNase H1 reversed the sensitivity of PBRM1-deficient cells to PARP inhibitors, suggesting that excessive levels of R-loops could be a cause of this synthetic lethality. PARP and ATR inhibitors also induced cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) innate immune signaling in PBRM1-defective tumor cells. Overall, these findings provide the preclinical basis for using PARP inhibitors in PBRM1-defective cancers. SIGNIFICANCE: This study demonstrates that PARP and ATR inhibitors are synthetic lethal with the loss of PBRM1, a PBAF-specific subunit, thus providing the rationale for assessing these inhibitors in patients with PBRM1-defective cancer. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/11/2888/F1.large.jpg.

Immune responses during COVID-19 infection.

Over the past 16 years, three coronaviruses (CoVs), severe acute respiratory syndrome CoV (SARS-CoV) in 2002, Middle East respiratory syndrome CoV (MERS-CoV) in 2012 and 2015, and SARS-CoV-2 in 2020, have been causing severe and fatal human epidemics. The unpredictability of coronavirus disease-19 (COVID-19) poses a major burden on health care and economic systems across the world. This is caused by the paucity of in-depth knowledge of the risk factors for severe COVID-19, insufficient diagnostic tools for the detection of SARS-CoV-2, as well as the absence of specific and effective drug treatments. While protective humoral and cellular immune responses are usually mounted against these betacoronaviruses, immune responses to SARS-CoV2 sometimes derail towards inflammatory tissue damage, leading to rapid admissions to intensive care units. The lack of knowledge on mechanisms that tilt the balance between these two opposite outcomes poses major threats to many ongoing clinical trials dealing with immunostimulatory or immunoregulatory therapeutics. This review will discuss innate and cognate immune responses underlying protective or deleterious immune reactions against these pathogenic coronaviruses.

Elevated Calprotectin and Abnormal Myeloid Cell Subsets Discriminate Severe from Mild COVID-19.

Blood myeloid cells are known to be dysregulated in coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2. It is unknown whether the innate myeloid response differs with disease severity and whether markers of innate immunity discriminate high-risk patients. Thus, we performed high-dimensional flow cytometry and single-cell RNA sequencing of COVID-19 patient peripheral blood cells and detected disappearance of non-classical CD14LowCD16High monocytes, accumulation of HLA-DRLow classical monocytes (Human Leukocyte Antigen - DR isotype), and release of massive amounts of calprotectin (S100A8/S100A9) in severe cases. Immature CD10LowCD101-CXCR4+/- neutrophils with an immunosuppressive profile accumulated in the blood and lungs, suggesting emergency myelopoiesis. Finally, we show that calprotectin plasma level and a routine flow cytometry assay detecting decreased frequencies of non-classical monocytes could discriminate patients who develop a severe form of COVID-19, suggesting a predictive value that deserves prospective evaluation.

Combination treatments with immunotherapy in brain metastases patients.

Immune checkpoint inhibitors (ICI) have revolutionized the treatment of many advanced cancers. However, in most pivotal trials, patients with brain metastases (BM) were either excluded, or only selected patients were allowed. Therefore, there are still some concerns about the safety/efficacy ratio of ICI in patients with BM. In this special report we will provide an overview on the biological rationale for using ICI in the treatment of BM, the reported BM-related outcomes of clinical trials with a focus on ICI plus chemotherapy and ICI plus ICI combinations. Last, we will provide future challenges with this strategy, as well as directions for future research.

Quality of Life During Chemotherapy for Breast Cancer in a West African Population in Dakar, Senegal: A Prospective Study.

PURPOSE: The prevalence of breast cancer is increasing in low- to middle-income countries such as Senegal. Our prospective study assessed the quality of life (QoL) of patients with breast cancer undergoing chemotherapy in Senegal. PATIENTS AND METHODS: Our study included women with breast cancer undergoing chemotherapy as initial treatment at the Center Aristide Le Dantec University Hospital in Dakar. Clinical, sociodemographic, and QoL data were collected and analyzed at three different times: baseline, 3 months, and 6 months after the start of systemic therapy. Health-related QoL was assessed using a Functional Assessment of Cancer Therapies-Breast (FACT-B) questionnaire after translation into the Wolof language. Linear mixed-effects models were performed to assess the changes in QoL scores. RESULTS: Between July 2017 and February 2018, 120 patients were included in the study. Their median age was 45 years. Most patients (n = 105; 92%) had locally advanced disease (T3 to T4 stage) and lymph node involvement (n = 103; 88%), and half had metastatic disease. The FACT-B total scores significantly improved over time (ß = 1.58; 95% CI, 0.50 to 2.67; P < .01). Nausea and vomiting were significantly associated with a decrease in FACT-B total scores (ß = -16.89, 95% CI, -29.58 to -4.24, P = .012; and ß = -13.44, 95% CI, -25.15 to -1.72, P = .028, respectively). CONCLUSION: Our study confirmed the feasibility of standardized QoL assessment in Senegalese patients with breast cancer. Our results indicated a potential improvement of QoL over the course of chemotherapy. Optimizing nausea and vomiting prevention may improve QoL.

Survival of patients with non-small cell lung cancer having leptomeningeal metastases treated with immune checkpoint inhibitors.

INTRODUCTION: Patients with non-small cell lung cancer (NSCLC) experience leptomeningeal metastases (LM) in 3-9% of cases. Because overall survival (OS) and performance status are very poor, they are mostly excluded from clinical trials. Here, we evaluated survival of patients with NSCLC having LM treated with immune checkpoint inhibitors (ICIs). METHODS: A prospectively collected list of patients with advanced NSCLC treated with ICIs between November 2012 and July 2018 in 7 European centres was merged. All patients with LM before ICI start were selected, data were retrospectively added and patients were classified according to the National Comprehensive Cancer Network (NCCN) LM prognostic classification (good/poor). Progression-free survival (PFS) and OS on ICIs were evaluated. RESULTS: Nineteen of 1288 (1.5%) patients had LM; 73.7% had synchronous brain metastases; 73.7% had neurological symptoms at the start of ICIs and 52.6% were in the NCCN LM good prognosis group. Programmed death ligand-1 (PD-L1) expression was known for 42.1% of patients (87.5% positive). Median follow-up was 13 months from the start of ICIs, and median (95% confidence interval [CI]) PFS on ICIs was 2.0 (1.8-2.2) months. Six-month PFS rate was 21.0% and was significantly higher in the NCCN good versus poor prognostic group: 40% vs 0% (p = 0.05). Twelve-month PFS rate was 0%. Median (95% CI) OS from the start of ICIs was 3.7 (0.9-6.6) months. Six-month OS rate was 36.8%, and 12-month OS rate was 21.1%; both were not statistically significantly different for the good versus poor NCCN prognostic group (p = 0.40 and p = 0.56, respectively). CONCLUSION: Some patients with NSCLC having LM do benefit from ICI treatment; specifically, those in the NCCN LM good prognosis group can obtain a long survival.

Outcome of Patients with Non-Small Cell Lung Cancer and Brain Metastases Treated with Checkpoint Inhibitors.

INTRODUCTION: Although frequent in NSCLC, patients with brain metastases (BMs) are often excluded from immune checkpoint inhibitor (ICI) trials. We evaluated BM outcome in a less-selected NSCLC cohort. METHODS: Data from consecutive patients with advanced ICI-treated NSCLC were collected. Active BMs were defined as new and/or growing lesions without any subsequent local treatment before the start of ICI treatment. Objective response rate (ORR), progression-free survival, and overall survival (OS) were evaluated. Multivariate analyses were performed by using a Cox proportional hazards model and logistic regression. RESULTS: A total of 1025 patients were included; the median follow-up time from start of ICI treatment was 15.8 months. Of these patients, 255 (24.9%) had BMs (39.2% active, 14.3% symptomatic, and 27.4% being treated with steroids). Disease-specific Graded Prognostic Assessment (ds-GPA) score was known for 94.5% of patients (35.7% with a score of 0-1, 58.5% with a score of 1.5-2.5, and 5.8% with a score of 3). The ORRs with BM versus without BM were similar: 20.6% (with BM) versus 22.7% (without BM) (p = 0.484). The intracranial ORR (active BM with follow-up brain imaging [n = 73]) was 27.3%. The median progression-free survival times were 1.7 (95% confidence interval [CI]: 1.5-2.1) and 2.1 (95% CI: 1.9-2.5) months, respectively (p = 0.009). Of the patients with BMs, 12.7% had a dissociated cranial-extracranial response and two (0.8%) had brain pseudoprogression. Brain progression occurred more in active BM than in stable BM (54.2% versus 30% [p < 0.001]). The median OS times were 8.6 months (95% CI: 6.8-12.0) with BM and 11.4 months (95% CI: 8.6-13.8) months with no BM (p = 0.035). In the BM subgroup multivariate analysis, corticosteroid use (hazard ratio [HR] = 2.37) was associated with poorer OS, whereas stable BMs (HR = 0.62) and higher ds-GPA classification (HR = 0.48-0.52) were associated with improved OS. CONCLUSION: In multivariate analysis BMs are not associated with a poorer survival in patients with ICI-treated NSCLC. Stable patients with BM without baseline corticosteroids and a good ds-GPA classification have the best prognosis.

PARP inhibition enhances tumor cell-intrinsic immunity in ERCC1-deficient non-small cell lung cancer.

The cyclic GMP-AMP synthase/stimulator of IFN genes (cGAS/STING) pathway detects cytosolic DNA to activate innate immune responses. Poly(ADP-ribose) polymerase inhibitors (PARPi) selectively target cancer cells with DNA repair deficiencies such as those caused by BRCA1 mutations or ERCC1 defects. Using isogenic cell lines and patient-derived samples, we showed that ERCC1-defective non-small cell lung cancer (NSCLC) cells exhibit an enhanced type I IFN transcriptomic signature and that low ERCC1 expression correlates with increased lymphocytic infiltration. We demonstrated that clinical PARPi, including olaparib and rucaparib, have cell-autonomous immunomodulatory properties in ERCC1-defective NSCLC and BRCA1-defective triple-negative breast cancer (TNBC) cells. Mechanistically, PARPi generated cytoplasmic chromatin fragments with characteristics of micronuclei; these were found to activate cGAS/STING, downstream type I IFN signaling, and CCL5 secretion. Importantly, these effects were suppressed in PARP1-null TNBC cells, suggesting that this phenotype resulted from an on-target effect of PARPi on PARP1. PARPi also potentiated IFN-γ-induced PD-L1 expression in NSCLC cell lines and in fresh patient tumor cells; this effect was enhanced in ERCC1-deficient contexts. Our data provide a preclinical rationale for using PARPi as immunomodulatory agents in appropriately molecularly selected populations.

Patient-reported tolerability of adverse events in phase 1 trials.

BACKGROUND: Phase I experts recommend revisiting dose-limiting toxicity (DLT) definition to include chronic and cumulative toxicities induced by new molecularly targeted therapies. Patient's assessment of late toxicities' tolerability is, however, unknown. MATERIALS AND METHODS: A prospective survey on adverse events (AEs) tolerability on 23 National Cancer InstituteCommon Terminology Criteria for Adverse Event, Version 4 (NCI-CTCAE.v4) items was conducted at Gustave Roussy's Phase I department. Patients' maximum tolerability duration was recorded at baseline, during trial and at trial completion. Results were compared with the corresponding physicians' survey. RESULTS: 52 patients enrolled in 27 Phase I trials between May 2014 and November 2015 completed 102 forms. At baseline, the most feared G2/G3 AEs were haematuria (74%), vomiting (71%) and hyperglycemia (64%)/dry mouth (94%), hyperglycemia (92%) and vomiting (92%). At trial completion, the most feared G2/G3 AEs were personality change (83.3%), haematuria (82%) and fever (80%)/dry mouth, fever and dizziness (100% each). Tolerability score did not differ over time. More previous treatments and occurrence of severe AEs were associated with better tolerability at study completion (p=0.0234 and p=0.0153, respectively, in multivariate analysis). Patient's tolerability differed from physician's assessment. CONCLUSION: AEs considered intolerable by patients are toxicities that directly impact their quality of life and differ from those feared by physicians or included in DLT definition. Patient-reported tolerability of AEs may help in optimising drug development.