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Introduction There is a major health problem due to the occupational related exposures to mineral particles, metals, and dust. Pathologists never report the presence of a possible metal-related aetiology in a specimen by lack of available technology. Therefore, several respiratory diseases are considered idiopathic. We recently developed an all-optical method, fully compatible with standard microscopy systems, for multi-elemental imaging of biological tissues. Methods Our instrument is based on Laser Induced Breakdown Spectroscopy ( LIBS ) and allows the in situ imaging and quantification of the elements of the periodic table within biological tissues. A laser is focused on the sample surface. Elemental images (maps) are obtained by scanning the surface of the specimen. Spectrometers collect the signal of various elements such as Fe-Ca-Na-P-Mg-Zn-Al-Mn-Co-Si-Cr-Ti and Cu in the tissue. Results We identified and mapped the presence of high levels of Si and Al, but also Ti, or Cr in lung and mediastinal lymph nodes biopsies from exposed workers suffering from sarcoidosis or idiopathic pulmonary fibrosis. We found different elements including Lithium in the lymph node of a sarcoidosis patient working in a lithium-battery factory. We were also able to image the presence of Beryllium in the lungs of a patient with Chronic Beryllium Disease. As a matter of fact, Lithium and Beryllium are light-weight elements not detectable by any other elemental imaging technique. We will describe a panel of recent results obtained with LIBS, and confirmed with electron microscopy, focusing on respiratory diseases. Discussion This laser spectrometry technique is versatile because almost any element can be imaged with high sensitivity. These results demonstrate the strong potential of this disruptive technology as a complementary tool for routine classical in-situ pathology examination of human tissues embedded in paraffin , especially for idiopathic respiratory diseases related to occupational or environmental exposure to metals, dust, or particles.

Introduction Lung cancer is the leading cause of mortality by cancer in the world. There is an urgent need to propose new therapeutic approaches in addition to conventional therapy. To be efficient and to decrease side effects, treatments must specifically reach tumors. In this context, this work aims to develop a new nanocarrier, able to target tumors and to measure its benefit in cancer therapy. The nanoparticles (Np) we used here combine a biodegradable polypeptide, and the Hyaluronan (Hya), the natural ligand of the CD44 receptors upregulated on cancer cells. Methods The ability of Hya fragments with different molecular weights (5000 and 35000 Da), or Np with different sizes (30 and 300 nm), to target the CD44 receptors was studied in vitro using lung cancer cell lines (H358, H460, A549, H322), in which CD44 expression level was measured. We investigated Hya and Np accumulation in tumor in vivo using an orthotopic lung cancer model, after administration by systemic route (IV injections) or pulmonary route (nebulization). We also analysed the accumulation of an anti-CD44 antibody in vivo. Noninvasive optical imaging techniques (2D and 3D fluorescence) allowed the real-time follow-up of the Np in mice. Results Binding of Hya fragments on cell lines was dose-dependent, with a higher affinity for the low molecular weight Hya. Np bound lung cancer cells and were internalized at 37 °C. This interaction was partially dependent to CD44 expression level. In vivo, we observed a better accumulation of the anti-CD44 antibody administered by nebulization, in tumor-bearing mice, compared to healthy mice. In contrast, no specific accumulation of Hya or Np was observed in tumors after nebulization. The nebulized Np showed long time retention in lungs. We observed a higher accumulation of Np, but not Hya, in the lungs of tumor-bearing mice compared to healthy mice, after IV injection. Conclusions We show that CD44 receptor is a pertinent target for lung cancer treatment. Despite the promising results obtained after anti-CD44 antibody nebulization, this way of administration seems less efficient to target tumor with Np. Our results will allow us to select the best Np formulation to load anticancer drugs. We will then evaluate the potential antitumor activity of drug-loaded Np using lung cancer model in mice.

Introduction Lung cancers are the fourth most common diagnosed cancer in the world and the main cause of cancer death. A large majority of lung cancers are classified as poor prognosis non-small cell lung cancers (NSCLC) with 5-year survival rate less than 15%. Most NSCLC cells resist to apoptosis and targeted therapies. To identify new molecules able to restore apoptosis in resistant NSCLC cells, a molecular high throughput screening was performed on NSCLC cells resistant to serum starvation. Seven thousand and five hundred molecules were screened at 2.5 μmol/L, and 71 compounds restoring apoptosis after primary and validation screenings on NSCLC cells, were selected. Among these molecules, we identified a family of compounds with a strong structural homology, known to inhibit kinase activity. Our goal is to develop new therapeutic strategies able to overcome resistance of NSCLC cells. Methods We selected 15 molecules of interest to identify the potential target(s) of these molecules by western blotting, RT-qPCR and immunofluorescence. We also assessed the effects of these compounds on NSCLC cells viability (MTS assay), apoptosis (Hoechst staining), and cell cycle (flow cytometry analysis). Results The 15 compounds showed IC50 ranging from 0.1 to 50 μmol/L. After 24 h treatment, the molecules induced G2/M cell cycle arrest, except the molecule 11, which strongly induced subG1 accumulation. The 15 molecules significantly restored serum deprivation-induced apoptosis in H358 NSCLC cells at 96 h. They also reduced cell viability in presence of serum, except the molecules 9 and 11. Most of the molecules decreased the expression level of EGFR and IGF1R and the phosphorylation level of Src, PKCδ, ERK and AKT. These 6 proteins are known as participating in apoptosis signalling pathways. Surprisingly, all compounds also reduced the level of tubulin and modified its network conformation. Conclusions The family of compounds that we identified is able to restore apoptosis in resistant NSCLC cells and could be used as new therapeutic approaches in NSCLC. We will assess the effects of combination therapies on resistant NSCLC cells, and determine the target(s) of these molecules by kinome array. This project will identify the best drug-candidate to counteract the NSCLC cells resistance, alone or in combination with targeted therapies.