Didier Lardinois

Anti-fibrotic effects of nintedanib in lung fibroblasts derived from patients with idiopathic pulmonary fibrosis

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive lung disease with poor prognosis. The kinase inhibitor nintedanib specific for vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) and fibroblast growth factor receptor (FGFR) significantly reduced the rate of decline of forced vital capacity versus placebo.AimTo determine the in vitro effect of nintedanib on primary human lung fibroblasts. Methods: Fibroblasts were isolated from lungs of IPF patients and from non-fibrotic controls. We assessed the effect of VEGF, PDGF-BB and basic FGF (bFGF) ± nintedanib on: (i) expression/activation of VEGFR, PDGFR, and FGFR, (ii) cell proliferation, secretion of (iii) matrix metalloproteinases (MMP), (iv) tissue inhibitor of metalloproteinase (TIMP), and (v) collagen.ResultsIPF fibroblasts expressed higher levels of PDGFR and FGFR than controls. PDGF-BB, bFGF, and VEGF caused a pro-proliferative effect which was prevented by nintedanib. Nintedanib enhanced the expression of pro-MMP-2, and inhibited the expression of TIMP-2. Transforming growth factor-beta-induced secretion of collagens was inhibited by nintedanib.ConclusionOur data demonstrate a significant anti-fibrotic effect of nintedanib in IPF fibroblasts. This effect consists of the drug’s anti-proliferative capacity, and on its effect on the extracellular matrix, the degradation of which seems to be enhanced.

Progression of Lung Cancer Is Associated with Increased Dysfunction of T Cells Defined by Coexpression of Multiple Inhibitory Receptors

T cells within non–small cell lung cancer tumors acquire greater numbers, and more diversity, of inhibitory receptors as tumors progress, correlating with a loss in function as well as in their ability to be reactivated after anti-checkpoint treatment. Dysfunctional T cells present in malignant lesions are characterized by a sustained and highly diverse expression of inhibitory receptors, also referred to as immune checkpoints. Yet, their relative functional significance in different cancer types remains incompletely understood. In this study, we provide a comprehensive characterization of the diversity and expression patterns of inhibitory receptors on tumor-infiltrating T cells from patients with non–small cell lung cancer. In spite of the large heterogeneity observed in the amount of PD-1, Tim-3, CTLA-4, LAG-3, and BTLA expressed on intratumoral CD8+ T cells from 32 patients, a clear correlation was established between increased expression of these inhibitory coreceptors and progression of the disease. Notably, the latter was accompanied by a progressively impaired capacity of T cells to respond to polyclonal activation. Coexpression of several inhibitory receptors was gradually acquired, with early PD-1 and late LAG-3/BTLA expression. PD-1 blockade was able to restore T-cell function only in a subset of patients. A high percentage of PD-1hi T cells was correlated with poor restoration of T-cell function upon PD-1 blockade. Of note, PD-1hi expression marked a particularly dysfunctional T-cell subset characterized by coexpression of multiple inhibitory receptors and thus may assist in identifying patients likely to respond to inhibitory receptor–specific antibodies. Overall, these data may provide a framework for future personalized T-cell–based therapies aiming at restoration of tumor-infiltrating lymphocyte effector functions. Cancer Immunol Res; 3(12); 1344–55. ©2015 AACR.

Microtubule-depolymerizing agents used in antibody-drug conjugates induce antitumor immunity by stimulation of dendritic cells.

Müller, Martin, von Bergwelt-Baildon, Zippelius, and colleagues show that the dolastatin family of microtubule inhibitors induced tumor-resident DC maturation and homing to draining lymph nodes to potentiate cellular antitumor immune responses, providing a rationale for combining dolastatin-based treatments with immunotherapy. Antibody–drug conjugates (ADC) are emerging as powerful treatment strategies with outstanding target-specificity and high therapeutic activity in patients with cancer. Brentuximab vedotin represents a first-in-class ADC directed against CD30+ malignancies. We hypothesized that its sustained clinical responses could be related to the stimulation of an anticancer immune response. In this study, we demonstrate that the dolastatin family of microtubule inhibitors, from which the cytotoxic component of brentuximab vedotin is derived, comprises potent inducers of phenotypic and functional dendritic cell (DC) maturation. In addition to the direct cytotoxic effect on tumor cells, dolastatins efficiently promoted antigen uptake and migration of tumor-resident DCs to the tumor-draining lymph nodes. Exposure of murine and human DCs to dolastatins significantly increased their capacity to prime T cells. Underlining the requirement of an intact host immune system for the full therapeutic benefit of dolastatins, the antitumor effect was far less pronounced in immunocompromised mice. We observed substantial therapeutic synergies when combining dolastatins with tumor antigen–specific vaccination or blockade of the PD-1–PD-L1 and CTLA-4 coinhibitory pathways. Ultimately, treatment with ADCs using dolastatins induces DC homing and activates cellular antitumor immune responses in patients. Our data reveal a novel mechanism of action for dolastatins and provide a strong rationale for clinical treatment regimens combining dolastatin-based therapies, such as brentuximab vedotin, with immune-based therapies. Cancer Immunol Res; 2(8); 741–55. ©2014 AACR.

Preoperative staging of non-small-cell lung cancer: comparison of whole-body diffusion-weighted magnetic resonance imaging and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography

AbstractObjectiveTo investigate the diagnostic value of whole-body magnetic resonance imaging (MRI) including diffusion-weighted imaging with background signal suppression (DWIBS) for preoperative assessment of non-small-cell lung cancer (NSCLC) in comparison to 18F-fluorodeoxyglucose 18FDG) positron emission tomography/computed tomography (PET/CT).MethodsThirty-three patients with suspected NSCLC were enrolled. Patients were examined before surgery with PET/CT and whole-body MRI including T1-weighted turbo spin echo (TSE), T2-weighted short tau inversion recovery (STIR) and DWIBS sequences (b = 0/800). Histological or cytological specimens were taken as standard of reference.ResultsWhole-body MRI with DWIBS as well as PET/CT provided diagnostic image quality in all cases. Sensitivity for primary tumour detection: MRI 93%, PET/CT 98%. T-staging accuracy: MRI 63%, PET/CT 56%. N-staging accuracy: MRI 66%, PET/CT 71%. UICC staging accuracy: MRI 66%, PET/CT 74%. Sensitivity for metastatic involvement of individual lymph node groups: MRI 44%, PET/CT 47%. Specificity for individual non-metastatic lymph node groups: MRI 93%, PET/CT 96%. Assessment accuracy for individual lymph node groups: MRI 85%, PET/CT 88%. Observer agreement rate for UICC staging: MRI 74%, PET/CT 90%.ConclusionWhole-body MRI with DWIBS provides comparable results to PET/CT in staging of NSCLC, but shows no superiority. Most relevant challenges for both techniques are T-staging accuracy and sensitivity for metastatic lymph node involvement.Key Points• Numerous radiological methods are available for the crucial staging of lung cancer • Whole-body DWIBS MRI provides comparable results to PET/CT in NSCLC staging. • No evident superiority of whole-body DWIBS over PET/CT in NSCLC staging. • Challenges for both techniques are T-staging and detection of small metastases.

Prognostic role of FGFR1 amplification in early-stage non-small cell lung cancer

Background:Recently, fibroblast growth factor receptor 1 (FGFR1) was discovered in squamous cell carcinomas (SCC) of the lung with FGFR1 amplification described as a promising predictive marker for anti-FGFR inhibitor treatment. Only few data are available regarding prevalence, prognostic significance and clinico-pathological characteristics of FGFR1-amplified and early-stage non-small cell lung carcinomas (NSCLC). We therefore investigated the FGFR1 gene status in a large number of well-characterised early-stage NSCLC.Methods:FGFR1 gene status was evaluated using a commercially available fluorescent in situ hybridisation (FISH) probe on a tissue microarray (TMA). This TMA harbours 329 resected, formalin-fixed and paraffin-embedded, nodal-negative NSCLC with a UICC stage I–II. The FISH results were correlated with clinico-pathological features and overall survival (OS).Results:The prevalence of an FGFR1 amplification was 12.5% (41/329) and was significantly (P<0.0001) higher in squamous cell carcinoma (SCC) (20.7%) than in adenocarcinoma (2.2%) and large cell carcinoma (13%). Multivariate analysis revealed significantly (P=0.0367) worse 5-year OS in patients with an FGFR1-amplified NSCLC.Conclusions:FGFR1 amplification is common in early-stage SCC of the lung and is an independent and adverse prognostic marker. Its potential role as a predictive marker for targeted therapies or adjuvant treatment needs further investigation.

High prevalence of infections and autoimmunity in patients with thymoma

The thymus selects T cells, thus ensuring T cell tolerance. Thymoma can be associated with immune dysregulation manifesting as autoimmunity and/or immunodeficiency. Immune dysregulation in thymoma patients has only been described in case reports and small case series. The current study was a retrospective single-center study, covering the period 1/2000 to 12/2010. Clinical data were collected by chart review. We identified 29 patients with thymoma. The median age at diagnosis was 60 years (range: 23-87). Median follow-up time was 1,326 days (range: 15-3,710), and 20 patients (69%) were alive at last follow-up. Overall, in 13 of 29 patients (45%) autoimmunity and infection were observed in 7 of 29 (24%) and 3 of 29 patients (10%) infection and autoimmunity only was observed, respectively. Both opportunistic and nonopportunistic infections were recorded. Myasthenia gravis (10 of 29 patients) was the most frequent autoimmune disease. Additional entities included pemphigus, pure red cell aplasia, lichen planus, Sjögrens syndrome, systemic lupus erythematosus (n = 2 each), and cutaneous lupus erythematosus, sarcoidosis, vitiligo, polymyositis, and chronic inflammatory demyelinating polyradiculoneuropathy (n = 1 each). Six of 29 patients (21%) had more than 1 autoimmune disorder. In thymoma patients, infection, autoimmunity, and in particular a combination of both pose a challenge to treating physicians. Prospective multicenter studies are required to more precisely define the thymoma-associated immune dysregulation syndrome.

Prospective study of a panfungal PCR assay followed by sequencing, for the detection of fungal DNA in normally sterile specimens in a clinical setting: a complementary tool in the diagnosis of invasive fungal disease?

We prospectively analyzed 34 clinical biopsy samples from 23 patients with a suspected invasive fungal infection by fungal culture, histology and a panfungal PCR followed by sequencing. Results were compared to the composite diagnosis according the European Organization for Research and Treatment of Cancer (EORTC) criteria. In 34 samples, culture, histology and panfungal PCR were positive in 35%, 38% and 62%, respectively. On the sample level the panfungal PCR revealed a sensitivity of 69% and a specificity of 62.5% compared to proven IFI according postoperative EORTC criteria. On patient level, the sensitivity of the PCR approach was 100%, specificity 62.5%.

The microtubule-depolymerizing agent ansamitocin P3 programs dendritic cells toward enhanced anti-tumor immunity

Abstract In addition to direct tumor cell cytotoxicity, chemotherapy can mediate tumor reduction through immune modulation of the tumor microenvironment to promote anti-tumor immunity. Mature dendritic cells (DCs) play key roles in priming robust immune responses in tumor-bearing hosts. Here, we screened a panel of 21 anticancer agents with defined molecular targets for their ability to induce direct maturation of DCs. We identified ansamitocin P3, a microtubule-depolymerizing agent, as a potent inducer of phenotypic and functional maturation of DCs. Exposure of both murine spleen-derived and human monocyte-derived DCs to ansamitocin P3 triggered up-regulation of maturation markers and production of pro-inflammatory cytokines, resulting in an enhanced T cell stimulatory capacity. Local administration of ansamitocin P3 induced maturation of skin Langerhans cells in vivo and promoted antigen uptake and extensive homing of tumor-resident DCs to tumor-draining lymph nodes. When used as an adjuvant in a specific vaccination approach, ansamitocin P3 dramatically increased activation of antigen-specific T cells. Finally, we demonstrate that ansamitocin P3, due to its immunomodulatory properties, acts in synergy with antibody-mediated blockade of the T cell inhibitory receptors PD-1 and CTLA-4. The combination treatment was most effective and induced durable growth inhibition of established tumors. Mechanistically, we observed a reduced regulatory T cell frequency and improved T cell effector function at the tumor site. Taken together, our study unravels an immune-based anti-tumor mechanism exploited by microtubule-depolymerizing agents, including ansamitocin P3, and paves the way for future clinical trials combining this class of agents with immunotherapy.

Bronchial Smooth Muscle Cells of Asthmatics Promote Angiogenesis through Elevated Secretion of CXC-Chemokines (ENA-78, GRO-α, and IL-8)

Background Airway wall remodelling is a key pathology of asthma. It includes thickening of the airway wall, hypertrophy and hyperplasia of bronchial smooth muscle cells (BSMC), as well as an increased vascularity of the sub-epithelial cell layer. BSMC are known to be the effector cells of bronchoconstriction, but they are increasingly recognized as an important source of inflammatory mediators and angiogenic factors. Objective To compare the angiogenic potential of BSMC of asthmatic and non-asthmatic patients and to identify asthma-specific angiogenic factors. Methods Primary BSMC were isolated from human airway tissue of asthmatic and non-asthmatic patients. Conditioned medium (CM) collected from BSMC isolates was tested for angiogenic capacity using the endothelial cell (EC)-spheroid in vitro angiogenesis assay. Angiogenic factors in CM were quantified using a human angiogenesis antibody array and enzyme linked immunosorbent assay. Results Induction of sprout outgrowth from EC-spheroids by CM of BSMC obtained from asthma patients was increased compared with CM of control BSMC (twofold, p < 0.001). Levels of ENA-78, GRO-α and IL-8 were significantly elevated in CM of BSMC from asthma patients (p < 0.05 vs. non-asthmatic patients). SB 265610, a competitive antagonist of chemokine (CXC-motif) receptor 2 (CXCR2), attenuated the increased sprout outgrowth induced by CM of asthma patient-derived BSMC. Conclusions BSMC isolated from asthma patients exhibit increased angiogenic potential. This effect is mediated through the CXCR2 ligands (ENA78, GRO-α and IL-8) produced by BSMC. Implications CXCR2 ligands may play a decisive role in directing the neovascularization in the sub-epithelial cell layers of the lungs of asthma patients. Counteracting the CXCR2-mediated neovascularization by pharmaceutical compounds may represent a novel strategy to reduce airway remodelling in asthma.

Cigarette smoke inhibits lung fibroblast proliferation by translational mechanisms

Cigarette smoke is a major cause of chronic obstructive pulmonary disease (COPD) and emphysema. Although cigarette smoke represses cellular proliferation, the molecular mechanisms underlying this phenomenon are unknown. CCAAT/enhancer-binding proteins (C/EBPs) are key regulators of cell cycle progression, differentiation and pro-inflammatory gene expression, are regulated predominantly at the translational level and may be involved in the pathogenesis of COPD. The aim of this study was to assess the effect of cigarette smoke on proliferation and the expression and translational regulation of C/EBP&agr; and C/EBP&bgr; in nondiseased primary human lung fibroblasts. Fibroblasts were exposed to cigarette smoke-conditioned medium (10% and 20% for 24 h). Proliferation was determined by [3H]thymidine incorporation. Protein expression levels were determined by immunoblotting and translation was monitored using a translation control reporter system. Cigarette smoke significantly reduced fibroblast proliferation and significantly upregulated full-length C/EBP&agr; and C/EBP&bgr; proteins due to a shift in the translational control of CEBPA and CEBPB mRNAs. This shift involved the re-initiation of mRNA translation via the regulatory upstream open reading frame, which coincided with increased interleukin-8 release and a decrease in functional elastin level. These findings provide a novel mechanism to understanding the tissue remodelling observed in the lungs of COPD patients.