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Supplementary file containing Supplementary Methods (pertaining to reagents, imaging, immunoblotting, cellular studies, microarray data, NF-κB ELISA, PCR, cell culture, histology, cytology, flow cytometry, constructs, and cellular Assays), 4 Supplementary Tables (pertaining to number of experimental mice, PCR primers, antibodies, and lentiviral shRNA pools), and 7 Supplementary Figures (described in the main and Supplementary text).

Although oncogenic activation of NFκB has been identified in various tumors, the NFκB–activating kinases (inhibitor of NFκB kinases, IKK) responsible for this are elusive. In this study, we determined the role of IKKα and IKKβ in KRAS-mutant lung adenocarcinomas induced by the carcinogen urethane and by respiratory epithelial expression of oncogenic KRASG12D. Using NFκB reporter mice and conditional deletions of IKKα and IKKβ, we identified two distinct early and late activation phases of NFκB during chemical and genetic lung adenocarcinoma development, which were characterized by nuclear translocation of RelB, IκBβ, and IKKα in tumor-initiated cells. IKKα was a cardinal tumor promoter in chemical and genetic KRAS-mutant lung adenocarcinoma, and respiratory epithelial IKKα-deficient mice were markedly protected from the disease. IKKα specifically cooperated with mutant KRAS for tumor induction in a cell-autonomous fashion, providing mutant cells with a survival advantage in vitro and in vivo. IKKα was highly expressed in human lung adenocarcinoma, and a heat shock protein 90 inhibitor that blocks IKK function delivered superior effects against KRAS-mutant lung adenocarcinoma compared with a specific IKKβ inhibitor. These results demonstrate an actionable requirement for IKKα in KRAS-mutant lung adenocarcinoma, marking the kinase as a therapeutic target against this disease.Significance: These findings report a novel requirement for IKKα in mutant KRAS lung tumor formation, with potential therapeutic applications. Cancer Res; 78(11); 2939–51. ©2018 AACR.

The potential of 2-benzothiazolyl-decorated liposomes as theragnostic systems for Alzheimer's disease was evaluated in vitro, using PEGylated liposomes that were decorated with two types of 2-benzothiazoles: (i) the unsubstituted 2-benzothiazole (BTH) and (ii) the 2-(4-aminophenyl)benzothiazole (AP-BTH). The lipid derivatives of both BTH-lipid and AP-BTH-lipid were synthesized, for insertion in liposome membranes. Liposomes (LIP) containing three different concentrations of benzothiazoles (5, 10, and 20%) were formulated, and their stability, integrity in the presence of serum proteins, and their ability to inhibit β-amyloid (1-42) (Αβ42) peptide aggregation (by circular dichroism (CD) and thioflavin T (ThT) assay), were evaluated. Additionally, the interaction of some LIP with an in vitro model of the blood-brain barrier (BBB) was studied. All liposome types ranged between 92 and 105 nm, with the exception of the 20% AP-BTH-LIP that were larger (180 nm). The 5 and 10% AP-BTH-LIP were stable when stored at 4 °C for 40 days and demonstrated high integrity in the presence of serum proteins for 7 days at 37 °C. Interestingly, CD experiments revealed that the AP-BTH-LIP substantially interacted with Αβ42 peptides and inhibited fibril formation, as verified by ThT assay, in contrast with the BTH-LIP, which had no effect. The 5 and 10% AP-BTH-LIP were the most effective in inhibiting Αβ42 fibril formation. Surprisingly, the AP-BTH-LIP, especially the 5% ones, demonstrated high interaction with brain endothelial cells and high capability to be transported across the BBB model. Taken together, the current results reveal that the 5% AP-BTH-LIP are of high interest as novel targeted theragnostic systems against AD, justifying further in vitro and in vivo exploitation.

Kirsten rat sarcoma virus (KRAS)-mutant cancers are frequent, metastatic, lethal, and largely undruggable. While interleukin (IL)-1β and nuclear factor (NF)-κB inhibition hold promise against cancer, untargeted treatments are not effective. Here, we show that human KRAS-mutant cancers are addicted to IL-1β via inflammatory versican signaling to macrophage inhibitor of NF-κB kinase (IKK) β. Human pan-cancer and experimental NF-κB reporter, transcriptome, and proteome screens reveal that KRAS-mutant tumors trigger macrophage IKKβ activation and IL-1β release via secretory versican. Tumor-specific versican silencing and macrophage-restricted IKKβ deletion prevents myeloid NF-κB activation and metastasis. Versican and IKKβ are mutually addicted and/or overexpressed in human cancers and possess diagnostic and prognostic power. Non-oncogene KRAS/IL-1β addiction is abolished by IL-1β and TLR1/2 inhibition, indicating cardinal and actionable roles for versican and IKKβ in metastasis.

Lung adenocarcinoma (LADC) is the leading cause of cancer death worldwide. Nevertheless, syngeneic mouse models of the disease are sparse, and cell lines suitable for transplantable and immunocompetent mouse models of LADC remain unmet needs. We established multiple mouse LADC cell lines by repeatedly exposing two mouse strains (FVB, Balb/c) to the tobacco carcinogens urethane or diethylnitrosamine and by culturing out the resulting lung tumours for prolonged periods of time. Characterization of the resulting cell lines (n = 7) showed that they were immortal and phenotypically stable in vitro, and oncogenic, metastatic and lethal in vivo. The primary tumours that gave rise to the cell lines, as well as secondary tumours generated by transplantation of the cell lines, displayed typical LADC features, such as glandular architecture and mucin and thyroid transcription factor 1 expression. Moreover, these cells exhibited marked molecular similarity with human smokers’ LADC, including carcinogen-specific Kras point mutations (KrasQ61R in urethane- and KrasQ61H in diethylnitrosamine-triggered cell lines) and Trp53 deletions and displayed stemness features. Interestingly, all cell lines overexpressed proliferin, a murine prolactin orthologue, which functioned as a lung tumour promoter. Furthermore, prolactin was overexpressed and portended poor prognosis in human LADC. In conclusion, we report the first LADC cell lines derived from mice exposed to tobacco carcinogens. These cells closely resemble human LADC and provide a valuable tool for the functional investigation of the pathobiology of the disease.

cAMP response element-binding protein (CREB) mediates proliferative and inflammatory gene transcription in neurodegeneration and cancer, but its role in malignant immune-evasion of lung adenocarcinoma (LUAD) is unknown. We show that human LUAD of smokers are frequently altered along the CREB pathway and we employ mouse models to discover that KRAS-mutant LUAD co- opt CREB to evade immune rejection by tumoricidal neutrophils. For this, KRAS- driven CREB activation suppresses CXC-chemokine expression and prevents recruitment of CXCR1+ neutrophils. CREB1 is shown to be pro-tumorigenic in five different LUAD models, a function that is dependent on host CXCR1. Pharmacologic CREB blockade prevents tumor growth and restores neutrophil recruitment only when initiated before immune-evasion of KRAS-mutant LUAD. CREB and CXCR1 expression in human LUAD are compartmentalized to tumor and stromal cells, respectively, while CREB-regulated genes and neutrophils impact survival. In summary, CREB-mediated immune evasion of KRAS-mutant LUAD relies on signaling to neutrophil CXCR1 and is actionable.

The mechanisms tumor cells use to hijack the immune system are largely uncharted. Here we used bioluminescent nuclear factor (NF)-κB reporter mice and macrophages to discover that metastatic tumors trigger NF-κB activation in host macrophages, dependent on mutant KRAS signaling and delivered via secretory versican. Versican activates NF-κB in tumor-associated macrophages via inhibitor of NF-κB kinase (IKK) β, resulting in release of interleukin (IL)-1β into the tumor microenvironment. Versican silencing in cancer cells or conditional IKKβ deletion in macrophages prevents myeloid NF-κB activation and metastasis. Versican is overexpressed and/or mutated in human cancers and metastatic effusions with KRAS mutations, predicts poor survival, can aid in the development of diagnostic platforms for pleural metastasis, and is druggable via toll-like receptor (TLR) 1/2 inhibition. The data indicate a cardinal role for tumor-derived versican in establishing cross-talk with macrophage IKKβ during metastasis and may foster the development of new therapies and diagnostic tools.

Herein we elaborated on methods to load cellular vesicles (CVs) and to incorporate cholesterol (Chol) and PEG lipids in their membrane, for enhancing the potential of such engineered CVs (e-CVs) as drug carriers. Hybrids formed by fusion between PEGylated liposomes (PEG-LIP) and CVs were evaluated as alternatives to e-CV, for the first time. Freeze-thawing cycles (FT) and incubation protocols were tested, and vesicle fusion was monitored by FRET dilution. B16F10, hCMEC/D3, and LLC cells were used for e-CV or hybrid development, and FITC-dextran as a model hydrophilic drug. Results show that dehydration rehydration vesicle (DRV) method is optimal for highest CV loading and integrity, while optimal protocols for Chol/PEG enrichment were identified. FT was found to be more efficient than incubation for hybrid formation. Interestingly, despite their high Chol content, CVs had very low integrity that was not increased by enrichment with Chol, but only after PEG coating; e-CVs demonstrated higher integrity than hybrids. Vesicle uptake by hCMEC cells is in the order: LIP

Liposomes are spherical vesicles composed of natural or artificial lipids and are used as drug carriers. However, their surface needs modification with ligands to target specific tissues. Cell-derived vesicles (CVs) are bioinspired drug carriers, as they are derived from cells by physical methods. Therefore, they preserve the topology and composition of the molecules present in the plasma membrane of the parental cell, enabling in vivo organotropism and specific drug delivery. The aim of this study is the investigation of the mechanisms by which liposomes and autologous CVs are internalized by three different breast cancer cell lines. The elucidation of the mechanism is likely to result in their optimization as drug carriers and the comprehension of their sub-cellular fate. More specifically, liposomes and CVs were produced, characterized, and loaded with the fluorescent dye FITC-dextran. Uptake experiments were performed using inhibitors of the clathrin-dependent or caveolin-dependent endocytic pathways and after incubating the cells at 4 °C, where energy dependent processes are inactivated. The results indicate that the endocytosis of CVs is active, mainly via the caveolin pathway, whereas liposomes are internalized actively by both pathways and also passively, as their uptake at 4 °C is not significantly hampered.

Triple-negative breast cancer (TNBC) is a highly aggressive type of cancer with limited therapeutic options. However, this type of cancer cells has shown overexpression of folate receptors, which bind with folic acid (FA) with high affinity. This feature can be used for targeting of nanocarriers, such as liposomes. In order to further examine the potential of increased efficacy by targeting the folate receptor, we prepared folate conjugated liposomes (DSPC/Chol/PEG/DSPE-PEG-FA) and loaded them with doxorubicin (DOX), an anticancer drug. For this, we first synthesized and verified the conjugate between FA and PEG-lipid (FA-PEG-lipid). After that, liposomes were prepared with thin film hydration method followed by probe sonication. Three different types of targeted liposomes having different concentrations of FA-PEG-lipid in their membranes (0.1 mol%, 0.5 mol%, and 1 mol%) were evaluated for their cytotoxicity (DOX-loaded liposomes) on MDA-MB-231 (epithelial human breast cancer cells), 4T1 (murine mammary carcinoma cells), and MCF7 (Human breast cancer cells); the two first are TNBC cells and overexpress FA receptor, the third does not. Cytotoxicity results proved that increasing amounts of FA on the surface of liposomes results in enhanced antitumor activity of liposomal-DOX in the case of the cancer cells, which overexpress the FA receptor.

The potential of 2-benzothiazolyl-decorated liposomes as theragnostic systems for Alzheimer's disease was evaluated in vitro, using PEGylated liposomes that were decorated with two types of 2-benzothiazoles: (i) the unsubstituted 2-benzothiazole (BTH) and (ii) the 2-(4-aminophenyl)benzothiazole (AP-BTH). The lipid derivatives of both BTH-lipid and AP-BTH-lipid were synthesized, for insertion in liposome membranes. Liposomes (LIP) containing three different concentrations of benzothiazoles (5, 10, and 20%) were formulated, and their stability, integrity in the presence of serum proteins, and their ability to inhibit β-amyloid (1-42) (Αβ42) peptide aggregation (by circular dichroism (CD) and thioflavin T (ThT) assay), were evaluated. Additionally, the interaction of some LIP with an in vitro model of the blood-brain barrier (BBB) was studied. All liposome types ranged between 92 and 105 nm, with the exception of the 20% AP-BTH-LIP that were larger (180 nm). The 5 and 10% AP-BTH-LIP were stable when stored at 4 °C for 40 days and demonstrated high integrity in the presence of serum proteins for 7 days at 37 °C. Interestingly, CD experiments revealed that the AP-BTH-LIP substantially interacted with Αβ42 peptides and inhibited fibril formation, as verified by ThT assay, in contrast with the BTH-LIP, which had no effect. The 5 and 10% AP-BTH-LIP were the most effective in inhibiting Αβ42 fibril formation. Surprisingly, the AP-BTH-LIP, especially the 5% ones, demonstrated high interaction with brain endothelial cells and high capability to be transported across the BBB model. Taken together, the current results reveal that the 5% AP-BTH-LIP are of high interest as novel targeted theragnostic systems against AD, justifying further in vitro and in vivo exploitation.

Anaplastic lympoma kinase (ALK) has been initially identified in anaplastic large-cell lymphomas in the form of fusion proteins. In lung cancer, 5-10% of patients present with EML4-ALK fusion genes. No involvement of wild-type ALK has been ever reported in lung cancer. In vitro data have suggested that ALK interacts with receptor protein tyrosine phosphatase zeta 1 (PTPRZ1) and the latter inhibits ALK tyrosine kinase (TK) activity. PTPRZ1 has been associated with various types of cancer, but its role in lung adenocarcinoma has not been studied. Here, we show that the ALK TK inhibitor (TKI) crizotinib abolished the increased lung carcinogenesis, angiogenesis and macrophage infiltration observed in Ptprz1-/- mice, with minimal effect in Ptprz1+/+ mice. Wild-type ALK phosphorylation and downstream signaling was enhanced in Ptprz1-/- tumors and lung microvascular endothelial cells (LMVECs). Genetic or pharmacological deletion of PTPRZ1 in LMVECs results in enhanced proliferation, migration, and tube formation in vitro, effects abolished by selective ALK TKIs. In human lung adenocarcinoma cells in vitro, low expression of PTPRZ1 correlates with K-Ras mutations and intense aggressiveness of the cancer cells and crizotinib abolishes this effect. Furthermore, low PTPRZ1 expression in human patient lung adenocarcinomas correlates with poor survival, while smokers or patients with K-Ras mutations have decreased PTPRZ1 expression and worse prognosis. All together these data suggest that low PTPRZ1 expression may act as an important biomarker for adenocarcinoma patients’ prognosis and responsiveness to ALK TKIs.

ImportancePleural effusions frequently signal disseminated cancer. Diagnostic markers of pleural malignancy at presentation that would assess cancer risk and would streamline diagnostic decisions remain unidentified.ObjectiveThe present study aimed at identifying and validating predictors of malignant pleural effusion at patient presentation.DESIGN, SETTING, AND PARTICIPANTSA consecutive cohort of 323 patients with pleural effusion (PE) from different etiologies were recruited between 2013-2017 and was retrospectively analyzed. Data included history, chest X-ray, and blood/pleural fluid cell counts and biochemistry. Group comparison, receiver-operator characteristics, unsupervised hierarchical clustering, binary logistic regression, and random forests were used to develop the malignant pleural effusion detection (MAPED) score. MAPED was validated in an independent retrospective UK cohort (n= 238).Main Outcomes and MeasuresThe outcome was diagnostic of pleural effusion in patients, and the clinical and laboratory indicators available of the patient were measured.ResultsFive variables showed significant diagnostic power and were incorporated into the 5-point MAPED score. Age > 55 years, effusion size > 50% of the most affected lung field, pleural neutrophil count < 2,500/mm3, effusion protein > 3.5 g/dL, and effusion lactate dehydrogenase > 250 U/L, each scoring one point, predicted underlying cancer with the area under curve(AUC) = 0.819 (sensitivity=82%, specificity=74%,P< 10-15) in the derivation cohort. The AUC and net reclassification improvement (NRI) of MAPED score and cytology were not significantly different. However, the integrated discrimination improvement (IDI) of The MAPED score displayed a slight increment(PConclusionsThe MAPED score identifies malignant pleural effusions with satisfactory accuracy and can be used complementary to cytology to streamline diagnostic procedures.

Lung cancer and chronic lung diseases impose major disease burdens worldwide and are caused by inhaled noxious agents including tobacco smoke. The cellular origins of environmental-induced lung tumors and of the dysfunctional airway and alveolar epithelial turnover observed with chronic lung diseases are unknown. To address this, we combined mouse models of genetic labeling and ablation of airway (club) and alveolar cells with exposure to environmental noxious and carcinogenic agents. Club cells are shown to survive KRAS mutations and to form lung tumors after tobacco carcinogen exposure. Increasing numbers of club cells are found in the alveoli with aging and after lung injury, but go undetected since they express alveolar proteins. Ablation of club cells prevents chemical lung tumors and causes alveolar destruction in adult mice. Hence club cells are important in alveolar maintenance and carcinogenesis and may be a therapeutic target against premalignancy and chronic lung disease., eLife digest The deadliest form of lung cancer is called lung adenocarcinoma, or LUAD. Tobacco chemicals often cause the disease by damaging the genetic information of lung cells. The damage leads to harmful changes in the DNA sequence which prompt the cells to form tumors. For instance, the most common of these changes takes place in a gene called KRAS. However, it is still unclear exactly which type of lung cells are more likely to develop into a tumor. In the lungs, airway epithelial cells cover the inside of the passages that bring the air inside little sacks called alveoli, which are lined by alveolar cells. Previous studies have used genetic methods to switch on the KRAS mutation in different compartments of the mouse lung. This showed that groups of airway cells, of alveolar cells, and of a class of cells located at the junction between airways and alveoli could all give rise to cancer. However, these experiments did not examine how tobacco chemicals could give rise to tumors in different groups of lung cells. Here, Spella et al. triggered LUAD in adult mice by exposing them to the toxic chemicals found in tobacco smoke, but without making any change to the KRAS gene. These mice also had genetically engineered reporters that could be used to deduce where the resulting tumors came from. DNA sequencing showed that the airway epithelial cells gained KRAS mutations after the chemical treatment. When the airway epithelial cells were experimentally removed before the treatments with tobacco chemicals, these mice did not get LUAD tumors. Spella et al. also observed that the tobacco-induced tumors came from the epithelial cells in the airways, and not from the cells in the alveoli. Moreover, when the lung was damaged, airway cells could move to the alveoli and start adopting the identity of alveolar cells, thereby replenishing this population. Together, these experiments imply that tobacco-induced LUAD starts in the airway epithelial cells. These findings suggest that airway epithelial cells could be targeted to stop lung cancer early on. Further studies should also examine how airway epithelial cells can transition to look more like alveolar cells when the lungs get harmed.

cAMP-response element binding protein (CREB) is an essential survival factor for normal respiratory epithelium, however, its role in lung cancer development has not been investigated. Our aim was to define the impact of CREB on KRAS -driven lung adenocarcinoma. Wild-type (W), conditional mutant KRAS- expressing ( LSL.KRAS G12D ; K), and Creb1 -deleted ( Creb1 f/f ; C) mice were intercrossed in all possible combinations, followed by intraperitoneal urethane or single intratracheal adenovirus (Ad)-Cre delivery.Conditional Creb1 -deleted lung cancer cell lines (CCLC) were derived from the lungs of urethane- but not Ad- Cre -treated C mice.(Ad)-Cre-treated C mice were markedly protected from urethane-triggered lung tumorigenesis compared with W controls [lung tumor mass, median(95%CI), respectively: 1(5-11) and 24(19-45) μL; P In vitro Cre-mediated Creb1 deletion or treatment of CCLC with CREB-inhibitor ICG-001 diminished cellular proliferation, in vivo tumor growth, and spontaneous lung metastasis. KRAS silencing in CCLC lead to decreased CREB activation, whereas microarray analysis of Creb-1 deleted CCLC revealed marked reductions in C-X-C chemokine expression. CREB signaling is essential for KRAS -driven lung adenocarcinoma by augmenting tumor-associated inflammation. This work was supported by European Research Council Starting Independent Investigator (#260524) and Proof-of-Concept (#679345) Grants.

Introduction Malignant pleural effusion (MPE) is primarily an immune-mediated manifestation of pleural-metastasized cancers, particularly adenocarcinomas that harbour KRAS mutations. We have previously determined that NF-κB activation in pleural tumor cells drives MPE formation, but the NF-kB pathways involved are obscure. Aims and objectives To investigate the relationship between mutant KRAS presence and NF-kB activation in pleural tumor cells that leads to MPE development. Methods We profiled baseline and host-microenvironment-induced NF-κB activity of tumor cells, and examined its relationship with KRAS status. We further silenced NF-kB activating kinases in tumor cells aiming to eliminate NF-kB activity and thus MPE competence. Results We found that mutant KRAS tumor cells were MPE competent and displayed IL-1b-induced IKKa nuclear translocation that was lost when KRAS was silenced. In contrast, wt KRAS cells did not form MPE and did not respond to IL-1b with nuclear IKKa shuttling. IKKa, but not IKKb, silencing of mutant KRAS tumors hampered their ability for MPE formation, suggesting a mutant KRAS -IKKa addiction in the pleural tumor cell during MPE development. Furthermore, IL-1b, but not TNFa, originated from host immune cells was required to sustain the MPE-competent phenotype of IKKa-addicted KRAS -mutant tumor cells. Microarray data showed that these cells secrete CXCL5 and CCl2 in response to IL-1b. Conclusions We demonstrate that KRAS -mutant tumor cells require host IL-1b signaling for MPE precipitation. This phenotype is mediated by IKKa. Acknowledgements These studies were supported by a European Research Council Starting Independent Investigator Grant (#260524). This abstract has been presented previously at the European Respiratory Society9s Lung Science Conference in March 2016 .

Background Carcinogen-inflicted human cancers, including lung tumours harbour thousands of mutations per genome, most of which are unknown (Garraway, LA et al, Cell 2013;153:17–37). Aim To develop a faithful mouse model of human tobacco carcinogen-induced lung adenocarcinoma suitable for the identification of novel oncogenic genes and pathways. Methods We repeatedly managed to obtain several murine lung adenocarcinoma cell lines (MLA) by chronically exposing various mouse strains to different tobacco carcinogens. MLA were characterised for cancer stemness and oncogenes, as well as global gene expression. Results To date, 12 MLA cell lines have been derived from Wt and transgenic mice on the FVB, Balb/c, and C57BL/6 strains by means of urethane or diethylnitrosamine exposure. All MLA were immortal, phenotypically stable, and indefinitely passaged in vitro over a period of over 18 months and/or 60 passages. In addition, all cell lines were oncogenic, transplantable, metastatic, and uniformly lethal in vivo. Interestingly, MLA displayed Kras mutations in codon 61, mono- or bi-allelic Trp53 loss, and expression of lung cancer stemness factors Itgb3 and Lgr6, in amazing similarity to human lung cancers. Microarray revealed that all MLA cell lines heavily overexpressed Prl2c2, encoding proliferin, in comparison to the native lungs. Prl2c2 silencing diminished MLA proliferation and stemness, to a degree comparable with Itgb3 interference. Conclusions MLA are faithful models of human lung adenocarcinoma that led to the discovery of Prl2c2 as a candidate lung tumour promoter. Funding European Research Council Starting Independent Investigator Grant #260524. Respire 2 European Respiratory Society Fellowship, European Respiratory Society Short Term Research Fellowship.

Increased expression of osteopontin (secreted phosphoprotein 1, SPP1) is associated with aggressive human lung adenocarcinoma (LADC), but its function remains unknown. Our aim was to determine the role of SPP1 in smoking-induced LADC. We combined mouse models of tobacco carcinogen-induced LADC, of deficiency of endogenous Spp1 alleles, and of adoptive pulmonary macrophage reconstitution to map the expression of SPP1 and its receptors and determine its impact during carcinogenesis. Co-expression of Spp1 and mutant KrasG12C in benign cells was employed to investigate SPP1/KRAS interactions in oncogenesis. Finally, intratracheal adenovirus encoding Cre recombinase was delivered to LSL.KRASG12D mice lacking endogenous or overexpressing transgenic Spp1 alleles. SPP1 was overexpressed in experimental and human LADC and portended poor survival. In response to two different smoke carcinogens, Spp1-deficient mice developed fewer and smaller LADC with decreased cellular survival and angiogenesis. Both lung epithelial- and macrophage-secreted SPP1 drove tumor-associated inflammation, while epithelial SPP1 promoted early tumorigenesis by fostering the survival of KRAS-mutated cells. Finally, loss and overexpression of Spp1 was, respectively, protective and deleterious for mice harboring KRASG12D-driven LADC. Our data support that SPP1 is functionally involved in early stages of airway epithelial carcinogenesis driven by smoking and mutant KRAS and may present an important therapeutic target.

Mast cells (MC) have been identified in human lung adenocarcinoma (LADC) tissues, but their functional role has not been investigated in vivo. For this, we applied three mouse models of KRAS-mutant LADC to two different MC-deficient mouse strains (cKitWsh and Cpa3.Cre). Moreover, we derived MC gene signatures from murine bone marrow-derived MC and used them to interrogate five human cohorts of LADC patients. Tumor-free cKitWsh and Cpa3.Cre mice were deficient in alveolar and skin KIT-dependent (KIT+) MC, but cKitWsh mice retained normal KIT-independent (KIT-) MC in the airways. Both KIT+ and KIT- MC infiltrated murine LADC to varying degrees, but KIT+ MC were more abundant and promoted LADC initiation and progression through interleukin-1β secretion. KIT+ MC and their transcriptional signature were significantly enriched in human LADC compared to adjacent normal tissue, especially in the subset of patients with KRAS mutations. Importantly, MC density increased with tumor stage and high overall expression of the KIT+ MC signature portended poor survival. Collectively, our results indicate that KIT+ MC foster LADC development and represent marked therapeutic targets.

Cellular vesicles (CVs) have been proposed as alternatives to exosomes for targeted drug delivery. CVs, prepared from human embryonic kidney 293 cells (HEK-293), C57BL/6 mouse B16F10 skin melanoma cells (B16F10), and immortalized human cerebral microvascular endothelial cells (hCMEC/D3) by liposome technology methods, were characterized for morphology, cytotoxicity, and cell uptake properties. CV brain-targeting potential was evaluated in vitro on the hCMEC/D3 blood-brain barrier (BBB) model, and in vivo/ex vivo. CV sizes were between 135 and 285 nm, and the ζ-potential was negative. The dehydration-rehydration method conferred highest calcein loading and latency to CVs compared with other methods. The increased calcein leakage from CVs when compared with liposomes indicated their poor integrity, which was increased by pegylation. The in vivo results confirmed lower liver uptake by PEG-CVs (compared with nonpegylated) proving that the calcein integrity test is useful for prediction of CV biodistribution, as used for liposomes. The cell uptake of homologous origin CVs was not always higher compared with that of non-homologous. Nevertheless, CVs from hCMEC/D3 demonstrated the highest BBB permeability (in vitro) compared with OX-26 targeted liposomes, and brain localization (in vivo). CVs from hCMEC/D3 cells grown in different media demonstrated decreased interaction with brain cells and brain localization. Significant differences in proteome of the two latter CV types were identified by proteomics, suggesting a potential methodology for identification of organotropism-determining CV components.

Lung adenocarcinoma (LUAD) and chronic lung diseases caused by smoking and environmental noxious agents are the deadliest diseases worldwide, sharing a partially charted pathobiology of dysfunctional alveolar repair. Here we sought to identify the respiratory epithelial dynamics and molecular signatures participating in adult lung maintenance and chemical carcinogenesis. We employed novel mouse models of respiratory epithelial marking and ablation, a battery of pulmonary toxins and carcinogens, experimental protocols of carcinogen-induced LUAD, tobacco carcinogen-induced LUAD cell lines, and human transcriptomic data and identified a prominent involvement of airway molecular programs in alveolar maintenance and carcinogen-induced LUAD. The airway-specific transcriptomic signature was redistributed to the alveoli after toxic and carcinogenic insults and resulted in marked contributions of airway-labeled cells to injury-recovered alveoli and LUAD. Airway cells maintained Kras mutations and therefore possibly contributed to lung cancer initiation, while LUAD were spatially linked to neighboring airways. Transcriptomic profiling of carcinogen-induced murine and human LUAD revealed enrichment in airway signatures, while ablation of airway cells distorted alveolar structure and function and protected mice from LUAD development. Collectively, these results indicate that airway cells and/or transcriptomic signatures are essential for alveolar maintenance and LUAD development.

Although oncogenic activation of NFκB has been identified in various tumors, the NFκB–activating kinases (inhibitor of NFκB kinases, IKK) responsible for this are elusive. In this study, we determined the role of IKKα and IKKβ in KRAS-mutant lung adenocarcinomas induced by the carcinogen urethane and by respiratory epithelial expression of oncogenic KRASG12D. Using NFκB reporter mice and conditional deletions of IKKα and IKKβ, we identified two distinct early and late activation phases of NFκB during chemical and genetic lung adenocarcinoma development, which were characterized by nuclear translocation of RelB, IκBβ, and IKKα in tumor-initiated cells. IKKα was a cardinal tumor promoter in chemical and genetic KRAS-mutant lung adenocarcinoma, and respiratory epithelial IKKα-deficient mice were markedly protected from the disease. IKKα specifically cooperated with mutant KRAS for tumor induction in a cell-autonomous fashion, providing mutant cells with a survival advantage in vitro and in vivo. IKKα was highly expressed in human lung adenocarcinoma, and a heat shock protein 90 inhibitor that blocks IKK function delivered superior effects against KRAS-mutant lung adenocarcinoma compared with a specific IKKβ inhibitor. These results demonstrate an actionable requirement for IKKα in KRAS-mutant lung adenocarcinoma, marking the kinase as a therapeutic target against this disease. Significance: These findings report a novel requirement for IKKα in mutant KRAS lung tumor formation, with potential therapeutic applications. Cancer Res; 78(11); 2939–51. ©2018 AACR.

Malignant pleural effusion (MPE) is a frequent metastatic manifestation of human cancers. While we previously identified KRAS mutations as molecular culprits of MPE formation, the underlying mechanism remained unknown. Here, we determine that non-canonical IKKα-RelB pathway activation of KRAS-mutant tumor cells mediates MPE development and this is fueled by host-provided interleukin IL-1β. Indeed, IKKα is required for the MPE-competence of KRAS-mutant tumor cells by activating non-canonical NF-κB signaling. IL-1β fuels addiction of mutant KRAS to IKKα resulting in increased CXCL1 secretion that fosters MPE-associated inflammation. Importantly, IL-1β-mediated NF-κB induction in KRAS-mutant tumor cells, as well as their resulting MPE-competence, can only be blocked by co-inhibition of both KRAS and IKKα, a strategy that overcomes drug resistance to individual treatments. Hence we show that mutant KRAS facilitates IKKα-mediated responsiveness of tumor cells to host IL-1β, thereby establishing a host-to-tumor signaling circuit that culminates in inflammatory MPE development and drug resistance., Malignant pleural effusion (MPE) is a life-threatening cancer-related disorder. Here, the authors show that KRAS-mutant tumor cells require IKKα, activated via host-provided IL-1β, to promote MPE development and that co-inhibition of both KRAS and IKKα ameliorates the development of MPE in mouse models.

Background: Malignant pleural mesothelioma (MPM) is a highly aggressive tumor linked to loss of tumor suppressorsBAP1, NF2, andTRP53and accompanied by malignant pleural effusion (MPE). Aim: To develop novel mouse models of MPM with MPE. Methods: Intercrosses of conditional mutantKRAS (LoxP-STOP-LoxP.KRASG12D; K) andTRP53-deleted (LoxP.Trp53.LoxP; P) mice received intrapleural adenovirus-Cre. Pleural tumors were molecularly phenotyped and cultured to isolate cell lines, which were inoculated into the pleurae of naive mice. Results: K mice developed lethal epithelioid MPM (median, 95%CI survival: 339, 285-379 days). KP mice succumbed to sarcomatoid MPM (median, 95%CI survival 40, 38-72 days) accompanied by MPE (mean±SD volume 349±269 µL). KP mice also developed peritoneal mesothelioma upon intraperitoneal adenovirus-Cre. Mouse MPMs expressed calretinin, podoplanin, and osteopontin, but not surfactant protein C. MPM cell lines were isolated from KP MPM, which transplanted MPM to naiveC57BL/6mice causing their death (median, 95%CI survival 26, 25-28 days) by MPE induction (mean±SD volume 387±180 µL). The models harbored secondary BAP1, NF2 and CDKN2 mutations. Treatment of KP mice with a KRAS inhibitor resulted in increased survival and halted MPM growth and MPE formation. Conclusions: We developed multiple models of primary and transplantable MPM that show thatKRASandTP53mutations can initiate the disease and cause secondaryBAP1andNF2loss. Funding ERC Grants #260524 and #679345.

Malignant pleural effusion (MPE) is the lethal consequence of various human cancers metastatic to the pleural cavity. However, the mechanisms responsible for the development of MPE are still obscure. Here we show that mutant KRAS is important for MPE induction in mice. Pleural disseminated, mutant KRAS bearing tumour cells upregulate and systemically release chemokine ligand 2 (CCL2) into the bloodstream to mobilize myeloid cells from the host bone marrow to the pleural space via the spleen. These cells promote MPE formation, as indicated by splenectomy and splenocyte restoration experiments. In addition, KRAS mutations are frequently detected in human MPE and cell lines isolated thereof, but are often lost during automated analyses, as indicated by manual versus automated examination of Sanger sequencing traces. Finally, the novel KRAS inhibitor deltarasin and a monoclonal antibody directed against CCL2 are equally effective against an experimental mouse model of MPE, a result that holds promise for future efficient therapies against the human condition., Malignant pleural effusion (MPE) is a lethal condition associated with various cancers. Here, the authors show that cancer cells with KRAS mutations promote MPE by recruiting myeloid cells via CCL2 signalling and that pharmaceutical targeting of KRAS results in reduced MPE incidence and volume in mouse models.

The lungs are frequently affected by cancer metastasis. Although NRAS mutations have been associated with metastatic potential, their exact role in lung homing is incompletely understood. We cross‐examined the genotype of various tumor cells with their ability for automatic pulmonary dissemination, modulated NRAS expression using RNA interference and NRAS overexpression, identified NRAS signaling partners by microarray, and validated them using Cxcr1‐ and Cxcr2‐deficient mice. Mouse models of spontaneous lung metastasis revealed that mutant or overexpressed NRAS promotes lung colonization by regulating interleukin‐8‐related chemokine expression, thereby initiating interactions between tumor cells, the pulmonary vasculature, and myeloid cells. Our results support a model where NRAS‐mutant, chemokine‐expressing circulating tumor cells target the CXCR1‐expressing lung vasculature and recruit CXCR2‐expressing myeloid cells to initiate metastasis. We further describe a clinically relevant approach to prevent NRAS‐driven pulmonary metastasis by inhibiting chemokine signaling. In conclusion, NRAS promotes the colonization of the lungs by various tumor types in mouse models. IL‐8‐related chemokines, NRAS signaling partners in this process, may constitute an important therapeutic target against pulmonary involvement by cancers of other organs.

Recently, the structure of BAY 58-2667 bound to the Nostoc sp. H-NOX domain was published. On the basis of this structural information, we designed BAY 58-2667 derivatives and tested their effects on soluble guanylyl cyclase (sGC) activity. Derivative 20 activated sGC 4.8-fold more than BAY 58-2667. Co-crystallization of 20 with the Ns H-NOX domain revealed that the increased conformational distortion at the C-terminal region of αF helix containing 110-114 residues contributes to the higher activation triggered by 20.

Background Nuclear factor (NF)-kB activation is essential for KRAS-mutant lung adenocarcinoma (Stathopoulos, G.T. et al. Proc Natl Acad Sci U S A 2007;104:18514-9 and Meylan, E. et al. Nature 2009;462:104-7). However, the relative contributions of NF-kB-activating kinases IKKa and IKKb are unknown. Aims To monitor and block NF-kB activation and IKK functions in lung adenocarcinoma. Methods NF-kB reporter mice and conditional IKKa/b gene deleted mice were used, which, respectively, express firefly luciferase in all somatic cells upon NF-kB activation, or lose the respective IKK gene upon CRE-mediated recombination. Lung adenocarcinomas were induced in these mice via ip injection of urethane (1 g/Kg) that is a tobacco carcinogen. Mutant KRAS-IKK interactions were studied using transfected benign HEK293T cells with mutant KRAS-and/or IKK-expression vectors. IKK-inhibitors are used in ADCA cell lines and KRAS-induced mice. Results Urethane caused strong NF-kB activation in the lungs, characterized by significant induction and nuclear translocation of IKKa, but not IKKb. Deletion of IKKa from the respiratory epithelium resulted in almost complete eradication of urethane-induced KRAS-mutant lung tumors, while deletion of IKKb was less protective. IKKb, but not IKKa, functioned as a tumor promoter in KRAS-wild-type HEK293T cells. However, only IKKa, and not IKKb, could render mutant KRAS-expressing HEK293T cells oncogenic in immunocompromized mice. In KRAS-IKKa-addicted tumorigenic HEK293T cells, IKKa resided in the nucleus.Dual IKK inhibitor is more effective in our models than IKKb inhibitor. Conclusions IKKa is required for KRAS-mediated lung adenocarcinoma. Funding European Research Council Starting Independent Investigator Grant #260524. This abstract has been presented previously at the European Respiratory Society9s Lung Science Conference in March 2016 .

Malignant pleural mesothelioma (MPM) is a highly aggressive tumor caused by asbestos. Faithful mouse models of the disease are missing. Our aim was to develop and characterize a conditional and transplantable mouse model of MPM. Conditional mutant KRAS -expressing ( LSL.KRAS G12D ; K) and TRP53 -deleted ( Trp53 f/f ; P) mice were intercrossed in all possible combinations, followed by intrapleural adenovirus-Cre. Efficient and widespread pleural recombination was verified using dual fluorescent Cre-reporter mice. Multiple cell lines were derived from primary MPM from KP mice and transplanted to C57BL/6 mice. KP mice developed multifocal lethal (median, 95%CI survival 40, 38-72 days) MPM with malignant pleural effusions (MPE; mean±SD volume 349±269 μL) involving both the visceral and parietal pleura and the mediastinum. KP-MPM expresses classical markers of human MPM and gives rise to multiple MPM cell lines (KPM). KPM are transplantable to C57BL/6 mice, leading to death (median, 95%CI survival 26, 25-28 days) and MPE (mean±SD volume 387±180 μL). Δ KRAS could be the tumor initiating gene of malignant pleural mesothelioma development and could present an important therapeutic target. European Research Council Starting Independent Investigator (#260524) and Proof-of-Concept (#679345) Grants.

Lung cancer and pulmonary fibrosis are common, yet distinct, pathological processes that represent urgent unmet medical needs. Striking clinical and mechanistic parallels exist between these distinct disease entities. The goal of this article is to examine lung fibrosis from the perspective of cancer-associated phenotypic hallmarks, to discuss areas of mechanistic overlap and distinction, and to highlight profibrotic mechanisms that contribute to carcinogenesis. Ultimately, we speculate that such comparisons might identify opportunities to leverage our current understanding of the pathobiology of each disease process in order to advance novel therapeutic approaches for both. We anticipate that such “outside the box” concepts could be translated to a more precise and individualised approach to fibrotic diseases of the lung.

The similarities between exosomes and liposomes, together with the high organotropism of several types of exosomes, have recently prompted the development of engineered-exosomes or exosome-mimetics, which may be artificial (liposomal) or cell-derived vesicles, as advanced platforms for targeted drug delivery. Here, we provide the current state-of-the-art of using exosome or exosome-inspired systems for drug delivery. We review the various approaches investigated and the shortcomings of each approach. Finally the challenges which have been identified to date in this field are summarized.

Background: Macrophages play a key role in neoplastic progression. We recently reported a profound tumor-protective effect of clodronate-mediated macrophage ablation against urethane (a smoke carcinogen)-induced lung oncogenesis (Zaynagetdinov, R. et al. J Immunol 2011;187:5703-11). Aims: To investigate the impact of genetic macrophage ablation on chemical-induced lung tumor development. Methods: Homozygote Dta f/f mice that express cell-suicidal Diphtheria toxin upon CRE recombinase-mediated recombination were crossed with Lyz2.Cre +/+ mice that express CRE specifically in macrophages. The above controls, as well as double heterozygote offspring Lyz2.Cre +/- ;Dta f/wt mice, all on the C57BL/6 background, received ten weekly doses of intraperitoneal urethane (1 g/Kg) to overcome the resistance of these mice to tumor induction, and lungs were retrieved six months after the first urethane dose for lung tumor examination. Results: Macrophage-deficient mice ( Lyz.Cre +/- ;Dta f/wt ) were markedly protected from urethane-induced lung tumor development compared with both Dta f/f and Lyz2.Cre +/+ controls. To this end, the number and diameter of urethane-triggered lung tumors in Lyz2.Cre +/+ (n = 13), Dta f/f (n = 8), and Lyz.Cre +/- ;Dta f/wt (n = 6) mice (mean±SEM) were 3.5±1.0, 2.3±0.6, and 0.3±0.2 (P Conclusions: These results corroborate that macrophages play a key role in tumor initiation and progression during chemical carcinogenesis in the respiratory tract. Funding: European Research Council Starting Independent Investigator Grant #260524.