Tesis sobre el tema "Lungs Differentiation"

Receptors for advanced glycation end-products (RAGE) are multi-ligand cell surface receptors highly expressed in the lung that modulate pulmonary inflammation during disease. However, the contributions of RAGE signaling are unknown during pulmonary organogenesis. In order to test the hypothesis that RAGE misexpression adversely affects lung morphogenesis, conditional transgenic mice were generated that over-express RAGE in alveolar type II cells of the lung. When RAGE is over-expressed throughout embryogenesis, severe lung hypoplasia ensues, culminating in perinatal lethality. Flow cytometry and immunohistochemistry employing cell-specific markers for various distal cell types demonstrated anomalies in key epithelial cell populations resulting from RAGE up-regulation through embryonic (E) 18.5. Electron microscopy also identified significant morphological disturbances to distal cell types including separation from the basement membrane. Possible mechanisms leading to the disappearance of pulmonary tissue by increased RAGE expression were then evaluated. A time course of lung organogenesis commencing at E12.5 demonstrated that increased RAGE expression primarily alters lung morphogenesis beginning at E16.5. TUNEL immunohistochemistry and immunoblotting for active caspase-3 confirm a shift toward apoptosis in lungs from RAGE over-expressing mice when compared to wild type controls. Assaying for NF-κB also revealed elevated nuclear translocation in lungs from transgenic mice compared to controls. An RT-PCR assessment of genes regulated by NF-κB demonstrated elevated expression of Fas ligand, suggesting increased activity of the Fas-mediated signal transduction pathway in which ligand-receptor interaction triggers cell death. These data provide evidence that RAGE expression must be tightly regulated during organogenesis. Furthermore, additional elucidation of RAGE signaling potentially involved in branching morphogenesis and cell cycle abnormalities may provide insight into the progression of RAGE-mediated lung diseases.

A Differentiation Factor (DF) was purified from rat lung conditioned medium by a four-steps procedure. The DF has a molecular weight of 27000, and an isoelectric point of 4.70. Although DF is stable up to 60°C, it is sensitive to digestion by trypsin, chymotrypsin and subtilisin. DF forms granulocyte colonies in soft agar. Studies using anti-NRK CSF antibody demonstrated that DF is distinct from GM-CSF.

Human embryonic stem cells (hESCs) show significant therapeutic potential in treating degenerative disorders. This is in part because of their ability to produce a limitless supply of starting cells and their potential to differentiate into more than 200 different cell types. The aim of the current research was to generate a robust stage wise protocol for the differentiation of hESCs to respiratory epithelial cells. The epithelial cells could then be used either for transplantation studies or, as an in vitro model for drug toxicity testing. In order to achieve this goal, we must identify the key steps in lung development and apply these to the differentiation protocol. In this study, we maintained Shef3 hESCs in their undifferentiated pluripotent state to expand the cells prior to the differentiated towards the definitive endoderm (DE) lineage. I used a two-stage protocol based on culture with a novel glycogen synthase kinase-3 (GSK-3) inhibitor (termed 1m), along with Activin-A. We confirmed the status of the cells by a combination of immunostaining and PCR. We showed loss of the pluripotency markers (Sox2 and Oct3/4) and gain of DE markers (Sox17, FoxA2 and CXCR4). After the induction of DE from hESCs, we then treated the cells with transforming growth factor (TGF)-β and bone morphogenetic protein (BMP) pathway inhibitors (SB431542 and Noggin respectively). This combinatorial treatment resulted in the differentiation into the anterior foregut endoderm (AFE) lineage based on expression of Pax9 and FoxA2 plus the up-regulation of Sox2. Further differentiation of AFE derivatives into more mature epithelial cells, termed lung progenitor cells (LPCs), was achieved following the treatment of AFE cells with a cocktail of trophic factors (BMP4, EGF, bFGF, FGF10, KGF and Wnt3a) yielded a population of NKX2.1-positive and FoxA2-positive cells that potentially corresponded to the lung lineage. Finally, prolonged treatment with FGF10 and FGF2 on LPC derived hESCs induced proximal (CC10, MUC5AC) and distal (SPB, SPC) airway epithelial cells. In addition, we also utilised the ectopic expression of an adenovirus expressing NKX2.1 to promote lung maturation. In conclusion, we have generated a protocol for the differentiation of hESCs into mature lung-like cells. The generation of these cells in vitro could potentially lead to a better in vitro model for toxicity testing and the development of novel therapies for promoting regeneration of lungs in patients with severe lung disorders.

Abstract Pulmonary fibrosis, lung cancer and chronic obstructive pulmonary disease (COPD) are severe diseases and common death causes worldwide. Due to the lack of an effective therapy, the investigation of cell biological mechanisms behind these diseases is essential. An activation of stromal cells, including myofibroblasts, is a main feature found in the pathogenesis of lung diseases. Myofibroblasts express alpha-smooth muscle actin (α-SMA), have specific ultrastructure, produce extracellular matrix proteins and possess contractile capacity. Detailed structure and function of myofibroblasts and their roles in healthy and diseased lung are not yet wholly understood. The investigation of the myofibroblasts may further offer novel tools for the acquisition of proper diagnosis, prognosis and medical treatment. The study aimed to characterize the ultrastructural, functional and disease-specific features of stromal cells, particularly myofibroblasts, in interstitial and malignant lung diseases. The functional properties evaluated here were differentiation, invasive and contractile properties. The study material included in vitro stromal cells cultured from bronchoalveolar lavage (BAL) fluids. The appearance and location of myofibroblasts in different lung compartments of non-smokers and the COPD-patients were examined in vivo. The cells were investigated by light and electron microscopy. The α-SMA expression was analysed by gene or protein assays. The study demonstrated that stromal cells could be cultured from diagnostic BAL fluid samples and lung tissues. Cultured cells were a mixture of fibroblasts and myofibroblasts. A small proportion of cells exhibited progenitor-like features. Myofibroblasts revealed differential features in electron microscopy and invasive or contractile assays. When studying tissues from healthy and COPD lungs, myofibroblasts were located both in alveoli and airways. In alveoli myofibroblasts localized in widened alveolar tips which were newly described structures and locations of myofibroblasts in healthy and diseased lung. The amount of myofibroblasts in large airways, but not in peripheral lung, was increased in COPD. We concluded that myofibroblasts have several locations in normal and COPD lung, which suggests a function both in pulmonary regeneration and the pathogenesis of COPD. Smoking altered the phenotype of myofibroblasts regardless of its origin<br>Tiivistelmä Keuhkofibroosi, keuhkosyöpä ja keuhkoahtaumatauti (COPD) ovat kansallisesti ja maailmanlaajuisesti yleisiä ja kuolemaan johtavia sairauksia. Taudinmääritys ja hoito ovat vaativia, eikä kaikille potilaille ole parantavaa hoitoa. Keuhkosairauksien kaikkia solubiologisia mekanismeja ei vielä tunneta, mikä on yksi syy lääkekehityksen ongelmiin. Interstitiaaleissa ja pahanlaatuisissa keuhkosairauksissa esiintyy paljon aktiivisia sidekudossoluja, kuten muuntuneita fibroblasteja eli myofibroblasteja. Ne tunnistetaan hienorakenteesta, jota voidaan tutkia elektronimikroskoopilla. Myofibroblastit ilmentävät myös solun sisäistä sileän lihaksen alfa-aktiinia (α-SMA), tuottavat sidekudoksen proteiineja ja kykenevät supistumaan. Myofibroblastien hienorakenteen ja toiminnan selvittäminen voi antaa lisätietoa keuhkosairauksien syntymekanismeista, jolloin diagnostiikkaa, ennustetta sekä hoitoja voidaan arvioida paremmin. Väitöskirjassa selvitettiin myofibroblastien hienorakennetta ja toimintaa eri keuhkosairauksissa. Tutkitut toiminnalliset ominaisuudet olivat erilaistumispotentiaali, invasiivisuus ja supistumiskyky. Sairauksien kliinistä käyttäytymistä ja potilaiden tupakointitottumuksia tarkasteltiin suhteessa solubiologiatason havaintoihin. Tutkimusmateriaali kerättiin taudinmäärityksen yhteydessä interstitiaalisia keuhkosairauksia, keuhkoahtaumatautia tai keuhkosyöpää sairastavilta potilailta. Tulosten mukaan bronkoalveolaarihuuhtelunesteestä (BAL) ja keuhkokudospaloista voidaan soluviljelymenetelmin kasvattaa ja ylläpitää solulinjoja. Viljellyt solut muodostivat sekasolupopulaatiota, joissa esiintyi pääosin fibroblasteja ja vaihteleva osuus myofibroblasteja. Pieni osa soluista ilmensi kantasoluille tyypillisiä piirteitä. Myofibroblastien tyyppipiirteet ja toiminnalliset ominaisuudet vaihtelivat taudeittain. Kudoksessa myofibroblasteja ilmentyi sekä keuhkorakkuloissa että ilmateissä. Keuhkorakkulatasolla myofibroblastit sijoittuivat irrallisten alveoliseinämien laajentuneisiin päihin, joita ei ole aiemmin tutkittu tieteellisessä kirjallisuudessa myofibroblastien yhteydessä. Keuhkoahtaumatauti ja tupakointi vähensivät näiden rakenteiden määrää perifeerisessä keuhkossa, kun taas suurissa ilmateissä keuhkoahtaumatauti lisäsi myofibroblasteja. Päättelimme, että myofibroblastit edistävät keuhkoahtaumataudin syntyä isoissa ilmateissä, mutta saattavat osallistua keuhkojen korjaukseen keuhkorakkuloissa ja pienissä ilmateissä

O epitélio pulmonar é formado por uma grande diversidade celular, que incluí: células secretoras, ciliadas, basais e neuroendócrinas (NE). A distribuição balanceada destes tipos celulares é crucial para a função pulmonar e pode ser dramaticamente alterada em doenças como a asma. Neste trabalho, estudamos o papel de Notch no pulmão em desenvolvimento ao inativar condicionalmente Rbpjk ou Pofut1, componentes críticos da sinalização Notch. Pulmões mutantes apresentaram-se superpopulados por células ciliadas e NE, além da ausência de células de Clara. Nossos dados sugeriram que Notch suprime os programas de diferenciação de células ciliadas e NE para permitir a diferenciação de células de Clara, através de um mecanismo de inibição lateral. Identificamos também genes associados com a diferenciação de células secretoras e ciliadas através de microarrays. A heterogeneidade no padrão de expressão gênica sugeriu que a via de sinalização Notch estabelece múltiplos subtipos de células ciliadas e secretoras no epitélio pulmonar em desenvolvimento.<br>The airway epithelium comprises a diverse population of secretory, ciliated, basal and neuroendocrine cells (NE). The proper balance of these cell types is critical for normal lung function and can be altered dramatically in conditions, such as asthma. We studied the role of Notch in airway progenitor cell fate by conditionally inactivating Rbpjk or Pofut1, two critical Notch pathway components in mouse mutants. This resulted in airways overpopulated with ciliated and NE cells and absence of secretory Clara cells. We found that Notch suppresses the ciliated and the NE cell programs to allow secretory cell differentiation through a lateral inhibition mechanism. We also identified genes associated with the differentiation of secretory and ciliated cells through a microarray gene profiling experiment. The great heterogeneity of gene expression patterns suggested that Notch plays a role in establishing multiple subsets of secretory and ciliated cells in the developing lung.

La voie Hedgehog (HH) est une voie de signalisation cruciale pour l’organogenèse et l’homéostasie. Etant donnée son implication dans la quiescence et la réparation pulmonaire ainsi que son altération dans des maladies respiratoires chroniques, nous avons exploré la présence et l’impact de la voie HH durant la différenciation de l’épithélium des voies aériennes et son incidence sur la genèse du remodelage épithélial caractéristique de la BPCO.Nous avons mis en évidence une corrélation entre l’expression des acteurs de la voie HH et la différenciation in vitro ainsi qu’une sécrétion du ligand principal de la voie, Sonic Hedgehog (Shh), par les cellules basales. In vitro, l’inhibition de la voie induit un remodelage caractéristique de la BPCO dont une réduction des cellules ciliées. Une altération de la signalisation HH chez les patients BPCO a été observée, particulièrement concernant l’expression et la localisation du facteur de transcription Gli2. Enfin, par une étude translationnelle, nous avons démontré la possibilité d’évaluer l’expression de la voie HH en routine clinique. Les données recueillies ont confirmé l’altération de la voie HH chez les patients BPCO en lien avec l’expression transcriptomique et protéomique de Gli2 associée à une baisse de la sécrétion du ligand Shh.Cette étude montre l’importance de la voie HH dans la différenciation des cellules épithéliales des voies aériennes et identifie pour la première fois une altération de cette voie chez les patients BPCO. La compréhension des mécanismes moléculaires associés à la pathogenèse en lien avec la voie HH ouvrirait la voie à de nouvelles stratégies thérapeutiques dans cette pathologie sans traitement<br>Hedgehog (HH) pathway is crucial for organogenesis and homeostasis. Since HH signaling is involved in pulmonary quiescence and repair, and altered in chronic lung diseases, we investigated HH signalling during airway epithelial cell differentiation and its incidence on Chronic Obstructive Pulmonary Disease (COPD)-associated remodeling.In vitro we demonstrated a correlation between HH pathway actors expression and differentiation. We identified basal cells as the source of the main ligand, Sonic Hedgehog (Shh). Preventing the ligand-induced HH activation led to the establishment of a remodeled epithelium with reduced cilliogenesis. We also observed HH signalling alteration in COPD patients, especially a loss of Gli2 transcription factor expression and localization. Finally, we revealed the possibility to evaluate HH expression in clinical routine. Our collected data confirm HH pathway alteration in COPD patients in correlation with Gli2 transcriptomic and proteomic expression associated with a decrease of Shh ligand secretion.This study highlights the importance of the HH pathway in airway epithelial cell differentiation and identifies for the first time an alteration of this pathway in COPD patient. Understanding the molecular mechanisms associated with HH pathway in pathogenesis would open the way to new therapeutic strategies in this disease lacking available treatments

CARM1 et PRMT1 sont 2 Protein Arginine MethylTransferases (PRMTs) impliquées dans la prolifération et dérégulées dans le cancer. La dimérisation est une caractéristique commune aux PRMTs. PRMT1 et CARM1 coopèrent dans la régulation des gènes mais il n'existe pas de données concernant un hétérodimère CARM1/PRMT1. Nous avons trouvé que PRMT1 et CARM1 sont surexprimées dans le cancer du poumon non à petites cellules et dans 2 lignées d'adénocarcinomes pulmonaires, A549 et H1299. Les siPRMT1 réduisent la prolifération cellulaire et facilitent la différentiation. Les siCARM1 produisent un effet similaire mais, comme ceci a déjà été décrit, suppriment l'expression de PRMT1 en plus de celle de CARM1. Ainsi, CARM1 peut-elle réduire la prolifération par un effet direct ou en inhibant PRMT1. Ce résultant souligne l'intérêt d'étudier la formation de l'hétérodimère CARM1/PRMT1. Nous avons trouvé que dans les cellules A549, CARM1 n'est pas phosphorylée sur la sérine 228, interagit avec PRMT1, méthyle les promoteurs de 2 gènes cibles (Sox2 et Nanog) et est localisée dans le noyau. Dans les cellules H1299, CARM1 est phosphorylée sur la sérine 228, n'interagit pas avec PRMT1, ne méthyle pas les promoteurs de Sox2 et Nanog et est localisée dans le cytoplasme. L'inhibition de la kinase MAP2K3 empêche la phosphorylation de CARM1 sur la sérine 228 et restaure l'interaction CARM1/PRMT1 dans les cellules H1299. En conclusion, l'invalidation de PRMT1 réduit la prolifération dans les cancers du poumon. L'invalidation de CARM1 réduit aussi la prolifération probablement par l'intermédiaire de la suppression de PRMT1. Nous suggérons que MAP2K3 est la kinase qui phosphoryle CARM1 sur la sérine 228 et que cette phosphorylation inhibe l'interaction CARM1/PRMT1. La formation de l'hétérodimère CARM1/PRMT1 pourrait constituer un moyen pour réguler l'activité de ces 2 enzymes<br>PRMT1 and CARM1 are 2 Protein Arginine MethylTransferases (PRMTs) implicated in cell proliferation and deregulated in cancer. Dimerisation is a conserved feature in the PRMT family. PRMT1 and CARM1 cooperate in gene regulation but CARM1/PRMT1 heterodimer is not yet characterised. We report that, PRMT1 and CARM1 are overexpressed in non-small cell lung cancer samples and in 2 lung adenocarcinoma cell lines, A549 and H1299. siPRMT1 reduce proliferation and promote differentiation. siCARM1 yield similar consequences but, as this was previously described, suppress PRMT1 expression in addition to CARM1 expression. Thus CARM1 might reduce proliferation by a direct effect or alternatively through PRMT1 suppression. This result reinforces the interest of investigating the CARM1/PRMT1 heterodimer formation. We found that in A549 cells, CARM1 is not phosphorylated at serine 228, interacts with PRMT1, methylates the promoter of 2 target genes (Sox2 and Nanog) and is localized in the nucleus. In H1299 cells, CARM1 is phosphorylated at serine 228, does not interact with PRMT1, does not methylate Sox2 and Nanog promoters and is localized in the cytoplasm. Inhibition of the kinase MAP2K3 prevents the phosphorylation of CARM1 at serine 228 and restores CARM1/PRMT1 interaction in H1299 cells. In conclusion, we propose that PRMT1 knock-down reduces proliferation in lung cancer. CARM1 knock-down reduces proliferation probably through the suppression of PRMT1. We suggest that MAP2K3 is the candidate kinase that phosphorylates CARM1 at serine 228 and that phosphorylation inhibits CARM1/PRMT1 interaction. CARM1/PRMT1 heterodimer formation might be a way of regulating the activities of these enzymes

Le thème des travaux qui fait l'objet de ce mémoire de thèse s'inscrit dans le cadre de la caractérisation de systèmes biologiques par modèles non entiers. Cette thèse comporte deux parties qui reposent sur deux collaborations distinctes. La première s'appuie sur une collaboration avec le laboratoire Mouvement Adaptation Cognition de l'Université Bordeaux 2 et l'institut Magendie de l'Inserm. L'objectif de ce travail consiste à étudier l'influence la longueur du muscle sur sa dynamique dans les cas de variations statiques et dynamiques de cette grandeur. La deuxième collaboration est un projet original, en partenariat avec l'équipe Anesthésiologie-Réanimation II du CHU Haut-Lévêque ayant pour but l'identification de transfert thermique dans le poumon au cours d'opération à cœur ouvert, grâce à des mesures obtenues sur des poumons de mouton.

The respiratory system represents a major interface between the body and the external environment. Its design includes a tree-like network of conducting tubules (airways) that carries air to millions of alveoli, where gas exchange occurs. The conducting airways are characterized by their great diversity in epithelial cell types with multiple populations of secretory, multiciliated, and neuroendocrine cells. How these different cell types arise and how these populations are balanced are questions still not well understood. Aberrant patterns of airway epithelial differentiation have been described in various human pulmonary diseases, chronic bronchitis, asthma, neuroendocrine hyperplasia of infancy, and others. The goal of this thesis is to investigate mechanisms of regulation of airway epithelial cell fate in the developing lung epithelium. More specifically, these studies focus on Notch signaling and address a long unresolved issue whether the different Notch ligands (Jagged and Delta) have distinct roles in the epithelial differentiation program of the extrapulmonary and intrapulmonary airways. Moreover, these studies investigate the ontogeny of the bHLH transcription factor Ascl1 and identify its targets in the developing airways as potential regulators of neuroepithelial body (NEB) size and maturation. My studies provide evidence that the Notch ligand families Jag and Dll are required for the specification and formation of different cell lineages in the developing airway epithelia. Jag ligands regulate multiciliated versus secretory (club) cell fates but also controls abundance of basal cell progenitors in extrapulmonary airways. Dll ligands regulate pulmonary neuroendocrine versus club cell fates in intrapulmonary airways. Analysis of mouse mutants showed that loss of Jag ligands has minimal impact on the size or abundance of NEBs and their associated secretory cells while loss of Dll ligands results in an expansion of NEB size and associated cells. To gain additional insights into the potential mechanisms of how neuroendocrine cells develop and undergo aberrant hyperplasia, I characterized the global transcriptional profile of embryonic lungs from mice deficient in Ascl1, which lack NEBs and neuroendocrine cells and identified a number of genes associated with neuroendocrine cell development, maturation, and the NEB microenvironment. Among these genes, components of the catecholamine biosynthesis pathway, such as tyrosine hydroxylase (Th), a key enzyme for catecholamine production, were downregulated in Ascl1 null lungs. Subsequent functional analysis using a pharmacological inhibitor of this pathway in lung organ cultures showed expansion of pulmonary neuroendocrine cells and NEB size, an observation of potential relevance in human diseases in which neuroendocrine cells are aberrantly expanded. Together these studies highlight the distinct role of Notch ligands and further implicate Ascl1 targets, as illustrated by catecholamine pathway components, in regulating epithelial cell fate. Further examination of these pathways may provide insights into the pathogenesis and ultimately therapeutic approaches for airway diseases.

"March 2001". Bibliography: leaves 193-238. Relates changes in the development of the pulmonary surfactant system in response to birth strategy, lung morphology and phylogeny in order to determine the extent of conservation in this process, by quantifying the total of phsospholipid, disaturated phospholipid and cholesterol in the lung washings of embryonic and hatchling chickens, oviparous bearded dragons and viviparous sleepy lizards, snapping turtles and green sea turtles throughout the final stages of incubation and gestation. Finds that the pattern of development of pulmonary surfactant lipids is consistent with that of mammals.

"March 2001".<br>Bibliography: leaves 193-238.<br>vii, 238 leaves : ill. (some col.) ; 30 cm.<br>Relates changes in the development of the pulmonary surfactant system in response to birth strategy, lung morphology and phylogeny in order to determine the extent of conservation in this process, by quantifying the total of phsospholipid, disaturated phospholipid and cholesterol in the lung washings of embryonic and hatchling chickens, oviparous bearded dragons and viviparous sleepy lizards, snapping turtles and green sea turtles throughout the final stages of incubation and gestation. Finds that the pattern of development of pulmonary surfactant lipids is consistent with that of mammals.<br>Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 2001

博士<br>國立臺灣大學<br>醫學研究所<br>79<br>Mucociliary clearance plays an important role in prlmonary defense mechanism. Abnormalities in mucociliary clearance are directly or indirectly related to various pulmonary desorders such se chromic bromchitis, bronchiectasis, cystic fibrosis, boinchial asthma, pneumonia and even lung cancer. There are two major functions of human respiratory epithelium: sceretion of viscoelastic mucus which can trap the inhaled potentially harmful particles and ciliary escalation which removes these foreign particles. At least eight different types of cells have been identified in human airway epithelium. Among them. mucous cell, ciliated cells and basal cells are the predominant three cell types. The mucous cells and ciliated cells are differentiated cells which contribute to the mucus secretion and ciliary transport. While the basal cells are the stem cells of the respiratory epithelium. When the respiratory mucous membranes are injured,the basal cells start to proliferate and differentiate into mucous cells and ciliated cells to replace the damaged epithelium. Althouge extensive works have been done in animal airway epithelium, the comtrol mechanism of mucus secretion and ciliary movement, as well as the regulation of basal cell proliferation and differentiation are still poorly understood. Wu and Lee first reported a serum-free, hormone-supplemented culture system for hamster and rabbit respiratory epithelium in 1982. In this culture system, the cultured respiratory epithelial cells are able to maintain mucus secretion and ciliary differentiation. We adapted this culture system and apply to the culture of human bromchial epithelial cells. We used this system to study the regulatory mechanisms of ciliary activity and mucus secretion. A total of 40 surgical specimens of normal human bromchial tissues were used in this study. The bronchial epithelial cells were dissociated by protease and cultured with F12 medium supplemented with insulin, transferren, epidermal growth factor, bovine hypothalamic extract, cholera toxin and hydrocortisone. The cultured bronchial epithelial cells were able to maintain mucous and ciliary differentiation when they are grown on the collagen substrata in the presence of vitamin A. The transmission electron microscopic and immunocytochemical studies with mucin monoclonal antibody confirmed the differentiated phenotypes in this culture model. * Regulation of Ciliary Activity in Cultured Human Bronchial Epithelial Cells Human bronchial epithelial cells cultured on collagen gel substrata in a serum-free F12 medium maintained differentiated phenotype with beating cilia. The ciliary beating frequency(CBF) could be measured with a computer assisted image analyzing system. We studied the ciliary activity of cultured bronchial epithelial cells from 21 adults and one 3 month-old fetus. The CBFs varied fron 8.1±1.0 Hz to 13.1±0.6 Hz and could last 2-3 weeks in culture. The CBF increased with the increase of temperature at a rate of 15 ±3 beats /℃ and reached a plateau at 40-45℃. The environment pH and presence of local anesthetic agents would affect on the ciliary activity. Isoproterenol (10-7M), terbutalina (10-6M), forskolin (10-5M), cAMP(10-6M), and isobutylmethylxanthine (10-4M), could stimulate ciliary activity and the increase of CBF was associated with the increase in intracellular cAMP level. Propranlol (10-6M) blocked the stinulatory effect caused by isoproternol. Renoual of calcium ion decreased 40% of CBF. These results suggest that calcium and cAMP are two important regulators for control of ciliary activity in cultured human bronchial epithelial cells. The single cilia beating pattern analysis by asymmetric illumination technique showed that the ciliary movement in culture composed of a recovery stroke and effective stroke with the duration ratio of 2:1. The cilia swipt an angle of 110。 (at 25℃, CBF 5Hz)which increased to 150。 after the stimulation of isoproterenol 10-6M (CBF 7.5Hz). This in vitro model provides an ideal system in the study of the regulation of human cilia kinetics. * Regulation of Mucus Secretion in Cultured Human Bronchial Epithelial Cells We established an ELISA system for mucin quantitation by monoclonal antibody against mucin (17Q2). This ELISA system was sensitive to detect 0.2 ng of mucin antigen. Using this ELISA technique, we are able to study the regulatory mechanisms of mucin production in cultured bronchial cells. We found that beta adrenergic agents could stimulate mucin production while propranolol inhibit mucin secretion. Atropine and acetylcholine had no effect on mucus secretion in cultured mucous cells. Pseudomonas ndotoxin, histamine, prostaglandin E2. prostaglandin F2 α, leukotriene C4 and D4 could also stimulate mucin production at high pharmacologic concentration. This in vitro moedl in conjunction with the mucin ELISA technique was a powerful tool to study the control of mucous cell secretion in human respiratory epithelium. * Growth and Differentiation of Lung Adenocarcinoma Cell Lines We nodified the culture methods for normal bronchial epithelial cells and established a culture system for human lung adenocarcinoma. The basal F12 medium was supplomented with selenium, insulin, transferrin, bovine hypothalamic extract, cholera toxin, epidernal growth factor and hydrocortisone. We have succeeded in the establishment of four adenocarcinoma cell lines from 12 clinical specimen. Three of the cell lines maintianed differentiated phenotype with glandular structure and mucin production. Using 3H-glucosamine as a mucin precursor to label the biosynthesis of mucin molecule, we had confirmed that CL2 lung adenocarcinoma cell lines could synthesize mucin. The intact mucin molecules were identified by chromatographic characteristics, enzyme digestion and immunoprecipitation. Although the CL2 cells could synthesize mucin, the mucin was cell-associated and did not release into the culture medium. The mucin production by CL2 cells be stimulated by 10-6M vitamin A (retinoic acid). Meanwhile, the growth of CL2 cells were inhibited in this concentration of vitamin A. The DNA synthesis by 3H-thymidine incoporation showed that vitamin A inhibited DNA synthesis by CL2 cells and there was a 48 hour latency period. The DNA flow cytometry study showed that the cell cycle distribution shifted in vitamin A treated CL2 cells. The S phase and G2-M phase cells were shifted to G0-G1 phase after treatment with vitamin A. These results indicate that vitamin Ainhibit CL2 cell growth by induction of mucin differentiation. * Basal cell Markers Studied by Monoclonal Antibodies Approach Basal cells of epithelium possess some biologic characteristics which are similar to transformed cancer cells, such as undifferentiation, ability to proliferate and unlimited life span. To fascilitate the study of proliferation and differentiation of basal cells, wedeveloped two monoclonal antibodies as basal cell marker with hybridoma technique. The immunogens were living CL2 cells. Immunofluorescense study showed that these two antibodies, S4 and M2, were specific for basal cells of skin, trachea and esophageal epithelium. These two antibodies could also be stained on the cancer cell lines and frozen tumor tissue sections of the lung and esophagus. Western blot analysis showed S4 antigen was a 160-180 kD protein and M2 antigen, 50 kD. Both M2 and S4 antigens were localized on the cell surface as confirmed by membrane immunofluorescence staining and surface protein labeling by 125I-lactoperoxidase system. Functional study of S4 antibody revealed that S4 antibody inhibited cell attachment and colony formation; while M2 antibody had no effect on cell attachment. The M2 antigens were preferentially expressed on lung cancer cells and viral transformed cells. These two monoclonal antibodies are useful markers to study the interaction between cell and cell, cell and matrix, as well as the growth and differentiation of basal cells. * Future Works The preferential expression of S4 and M2 antigens in undifferentiated basal cells and cancer cells suggests that these antigens are related to undifferentiation and cell proliferation. We are now interested in the gene expression of these antigens. Recently, we have identified a 1.5 kb cDNA clone by immunoscreening with M2 antibodies. Preliminary data of in situ hybridization using anti-sense RNA probe confirmed the basal localization of the complimentary mRNA. The Northern hybridization revraled a 2 to 4-fold increase of 2.0 kb mRNA expression in lung cancer cell lines as compared with the normal bronchial epithelial cells. Further studies are needed to confirm this cDNA clone. In conclusion, we have established an in vitro model to study the growth and differentiation of human bronchial epithelium. The ciliary kinetics can be studied by this clture system with a computed asisted image processing. The regulation of mucin production by mucous cells can be studied by this culture techmique with mucin ELISA assay. A systen for culturing lung abenocarcinoma cell line is also developed with a suscess rate of 30%. We also demonstrated that vitamin A retinoic acid can modulated cell growlth and mucin differentiation in a well differentiated lung adenocarcinoma cell line. This cell line can be used as a model to study the anti-tumor effect of vitamin A. Finally, we developed two monoclonal antibodies specific for undifferentiated basal cells. These two surface markers basal cell of may be potentially useful in the study of the control of differentiation and proliferation of basal stem cells.

碩士<br>高雄醫學大學<br>醫學研究所<br>99<br>Pulmonary fibrosis is a progressive process that leads to cough, shortening of breath, pulmonary hypertension and cardiopulmonary failure. Fibrosis is defined by the overgrowth, scarring of tissues and is attributed to excess deposition of extracellular matrix including collagen and fibronectin, leading to reduced pulmonary function. Environmental endocrine disruptors are compounds that interfere with human endocrine system and have been shown to be assotiated with many diseases. Therefore, the purpose of our study was to investigate the effects of environmental endocrine disruptors on pulmonary fibroblasts and the signaling transduction pathway involved. We found that environmental endocrine disruptors increased the ??-SMA protein expression in two lung fibroblast cell lines. The cell migration ability was increased by the treatment of the cells with environmental endocrine disruptors. TCDD also induced COX-2 protein expression and Aryl hydrocarbon receptor (AhR) nuclear localization. The expression of CYP1B1 gene confirmed the activation of AhR signaling pathway induced by TCDD. Calcium thermal imaging of the cells indicated that TCDD in-creased the intracellular calcium concentration in short-term treatment. Western bloting analysis showed that cytosolic phos-pholipase A2 (cPLA2) was induced after treatment of the cells with TCDD. The expression of ??-SMA and cPLA2 was reduced, while the expression of COX-2 increased in cells with AhR knockdown. According to these results, we suggested that TCDD induced fibroblast differentiation, migration, ??-SMA protein expression and cPLA2 protein expression through AhR signaling pathway. Therefore, TCDD induced the cal-cium-dependent inflammatory pathway may exacerbate lung fibroblasts differentiation and pulmonary fibrosis.

Tese de doutoramento em Medicina<br>As doenças de foro respiratório são altamente prevalentes a nível mundial, encontrando-se no grupo das doenças mais fatais em países desenvolvidos. Epitélio pulmonar gerado in-vitro a partir de células estaminais pluripotentes humanas tem aplicações em medicina regenerativa, no estabelecimento de novos modelos de doença, ensaios farmacológicos pré-clínicos e estudo do desenvolvimento humano. Neste trabalho descrevemos uma estratégia para gerar células da via aérea e alveolares maturas a partir de células estaminais pluripotentes humanas. Seguimos os paradigmas do desenvolvimento para gerar progenitores pulmonares (PPs) a partir das células estaminais e descobrimos que a glycogen synthase kinase 3 (GSK3) desempenha um papel central no balanço entre expansão de progenitores e a sua maturação em multi-linhagem. É importante realçar que a maioria das células geradas através do nosso método exibia características similares a células pulmonares pós-natais. Para além disso, o nosso modelo permitiu inferir um novo mecanismo envolvido no desenvolvimento pulmonar humano. Demonstramos que o efeito da inibição da maturação pela GSK3 no seu estado inibido é em parte devido à regulação do ciclo celular. Em culturas libertadas da inibição da GSK3, a via de sinalização NOTCH favorece a maturação dos PPs em populações epiteliais distais, inibindo as mais proximais, enquanto que a via WNT promove a maturação de células de Clara, implicando desta forma ambas as vias de sinalização no processo de especificação proximo-distal do epitélio pulmonar. Finalmente, demonstramos que o modelo desenvolvido é passível de ser utilizado com plataforma para desenvolvimento de modelos de doença respiratória humana e que poderá ser uma ferramenta importante para estudos sobre a fisiologia e importância de populações epiteliais pulmonares raras.<br>Respiratory diseases are highly prevalent worldwide and consistently rank within the group of the most fatal diseases in developed countries. Lung epithelium generated in-vitro from human pluripotent stem cells (hPSCs) has tremendous potential for applications in regenerative medicine, disease modeling, pre-clinical drug screenings and the study of human development. Here we describe a strategy to derive mature airway and alveolar lung epithelium from hPSCs. We followed developmental cues to derive hPSCs towards lung progenitors (LPs) and found that glycogen synthase kinase 3 (GSK3) plays a central role in the balance between progenitor expansion and multilineage maturation of LPs. Importantly, the majority of the cells generated by our method exhibited characteristics similar to those found in postnatal human lungs. Our model offers novel mechanistic insight into human lung development. We show that the maturation inhibiting effects of GSK3 inhibition (GSK3i) in our cultures is partly due to cell cycle regulation. In addition, upon release of GSK3i, NOTCH signaling induces a distal cell fate at the expense of proximal and ciliated cell fates, whereas WNT signaling promotes a proximal club cell fate, implicating both signaling pathways in proximodistal specification of the human lung. Finally, we demonstrate that the model we developed is suitable for modelling of human respiratory diseases and could be a valuable tool to study the physiology and relevance of rare lung epithelium populations.<br>National Institutes of Health (HL120046 and 1U01HL134760), the Thomas R Kully IPF Research Fund and the Portuguese Science Foundation (FCT) (PD/BD/52320/2013).

碩士<br>國立陽明大學<br>生化暨分子生物研究所<br>98<br>Hypoxia, a reduction of normal oxygen levels in cells or tissues, creates a variety of changes in cell metabolism including increased oxidative stress and DNA damage. Though Oct4, a homeobox transcription factor essential for self-renewal of stem cells, is expressed in various cancers, little is known about the functional role of Oct4 in tumorigenesis. In this study, we discovered that hypoxia induces a short isoform of Oct4, termed as Oct4B, in lung cancer through a HIF-2? dependent pathway. Overexpression of Oct4B induced cell proliferation and anchorage-independent growth of lung cancer, indicating the oncogenic potential of Oct4B. In addition, ectopic expression of Oct4B prevented cells from oxidative stress induced apoptosis, suggesting a functional role of Oct4B in anti-apoptosis. Overexpression of Oct4B promoted tumor formation in xenograft mouse model, demonstrating the positive involvement of Oct4B in tumorigenesis. We observed the increased activity of EGFR signaling in both hypoxia-treated or Oct4B-transfected cells. Q-PCR analysis demonstrated that Oct4B enhanced the transcript of TGF-?? a cognate ligand of EGFR. In addition, ectopic expression of Oct4B induced epithelial mesenchymal tans-differentiation and promoted cell migration. Through cDNA microarray and Q-PCR analyses, we identified that Oct4B induces Slug, a key effector in epithelial mesenchymal tans-differentiation.Thus, our results provide a novel mechanism that shows how Oct4B is induced by hypoxia to enable cancer cells to adapt environmental pressures and encourage malignancy in lung cancer

博士<br>國防醫學院<br>醫學科學研究所<br>106<br>A total of 520 patients with clinical early stage lung adenocarcinoma who underwent surgical resection were reviewed retrospectively. Clinical data and outcomes were evaluated with an average follow-up of 117 months. The results were validated via lung cancer cell line studies. The clinical parameters did not differ between relapse and nonrelapse patients. Exceptions were tumor differentiation, lymphovascular space invasion, F18-fluorodeoxyglucose maximum standard uptake value, tumor size, and pathological stage (p < 0.001). Poor tumor differentiation was the independent prognostic factor (odds ratio: 2.937, p =0.026). The expression of TTF-1 was correlated with tumor differentiation in resected lung adenocarcinoma patients (p < 0.001). Five-year survival was 60.0% for score 1 TTF-1 expression patients, 80.1% for score 2 TTF-1 expression patients, and 86.1% for score 3 TTF-1 expression group patients. The lung cancer cell line study of knockdown and overexpression of TTF-1 revealed TTF-1 mediated High Mobility Group AT-Hook 2 (HMGA2) protein involved with epithelium-mesenchymal transformation. The chromatin immunoprecipitation revealed TTF-1 regulated HMGA2 via direct binding. TTF-1/HMGA2 axis was associated with tumor differentiation and mediated the aggressiveness of the tumor and prognosis.

CCAAT/Enhancer Binding Protein Alpha (C/EBPa) is transcription factor protein involved in the differentiation of many cell types, including granulocytes and pulmonary cells. Studies have found that downregulation of C/EBPa leads to tumor formation in the hematopoietic system, bones, lungs, liver, and other organs. Mutations and post translational modifications can also reduce the function of C/EBPa in humans, leading to cancers. Recent studies have made progress in treating acute promyelocytic leukemia (APL), an M3 subtype of acute myeloid leukemia (AML), by incorporating all trans retinoic acid (ATRA) in targeted treatments. ATRA increases C/EBPa expression levels, thus promoting cell differentiation and subsequent apoptosis of leukemia cells. Still, survival rates of AML patients are low. In patients diagnosed with AML subtypes M4 or higher, ATRA does not work. In addition, patients can become resistant to ATRA, making it essential to find an alternative therapy. Therefore, novel drug treatments are necessary. Through a high throughput screening method, we have determined a potent chemical compound, ICCB280, that can enhance C/EBPa expression levels. However, ICCB280’s effective concentration for cell differentiation is relatively high, so we performed a structural-activity relationship (SAR) analysis and discovered a more potent chemical, styryl quinazolinone CCAAT/Enhancer Binding Protein Compound 73 (CEBP- 73). We tested CEBP-73 with two cell lines, HL-60 and A549, which represent leukemia and lung cancer models, respectively. We found that CEBP-73 increased C/EBPa expression levels in a time-dependent, dose-responsive manner in both leukemia cells and lung cancer cells. In western blot analyses, while both ICCB280 and CEBP-73 upregulated C/EBPa protein expression, more protein was expressed in leukemia and lung cancer cells treated with CEBP-73 in a dose-dependent manner than in cells treated with ICCB280. Next, we investigated CEBP-73’s effectiveness in upregulating C/EBPa’s downstream genes. We observed enhanced expression of CEBPe (HL-60 specific downstream gene) in HL-60 cells, and enhanced SPC, NKX2-1 (codes for TTF-1), and HIF-1a (A549 specific downstream genes) expression levels in A549 cells. To investigate the mechanisms of increased C/EBPa expression, we asked whether expression of an extra coding CEBPA (ecCEBPA), a noncoding RNA for C/EBPa that prevents methylation at the CEBPA gene promoter site, will increase. We found that CEBP-73 increased not only C/EBPa expression, but also ecCEBPA in HL-60 and A549 cells. This is the first study to our knowledge that confirms styryl quinazolinone CEBP- 73 can increase ecCEBPA expression. To examine the effectiveness of CEBP-73 in vivo, EGFR-L858R-T790M (EGFRTL/CCSP-rtTA) mice were administered a vehicle solution (control), 1 mg/kg of CEBP-73, or 10 mg/kg CEBP-73. The results showed a trend in CEBP-73 concentrations; higher doses of CEBP-73 induce higher levels of C/EBPa expression in lung tissue. Fewer and smaller tumors were present in lungs treated with CEBP-73 than lungs treated with a control. These findings support the role of CEBP-73 in enhancing C/EBPa expression, including upregulation at the promoter region of the CEBPA gene and at downstream gene loci. In addition, the study’s results affirm the role of C/EBPa as an inducer of cell differentiation in leukemia and lung cancer by showing neutrophils with segmented lobes and granules, indications of cell maturity, in cells treated with compounds that enhanced C/EBPa expression. These data suggest that CEBP-73 could provide novel therapeutic approaches in treating leukemia and lung cancer and could potentially be modified to treat other cancers in targeted drug therapies.

碩士<br>國立陽明大學<br>生化暨分子生物研究所<br>98<br>Aberrant expression and function of epidermal growth factor receptor (EGFR) is reported in most lung cancer cases. Sox2, a core transcription factor regulating self-renewal of stem cells, is highly expressed in lung cancer. We discovered that EGFR and its ligands (TGF-??nand EGF) induce Sox2 expression in lung cancer. Ectopic expression of c-Myc, a key effector of EGFR signaling, induced Sox2 expression; knockdown of c-Myc decreased Sox2 level in lung cancer, suggesting that EGFR induces Sox2 via a c-Myc dependent pathway. Ectopic expression of Sox2 promoted cell proliferation and anchorage-independent cell growth; knockdown of Sox2 attenuated oncogenic properties of lung cancer. In addition, Sox2-silencing induced autophagic death of lung cancer; overexpression of Sox2 prevented cell from starvation-induced autophagy. These data demonstrates that Sox2 induces oncogenesis of lung cancer. Overexpression of Sox2 promoted tumor growth in xenograft mouse model; knockdown of Sox2 inhibited tumor formation in vivo. These results support the notion that Sox2 enhances tumorigenesis of lung cancer. Through a cDNA microarray analysis for Sox2 target genes, we identified that Sox2 regulates EGFR. Immunoblotting showed that Sox2 induced EGFR expression, suggesting that an EGFR-Sox2-EGFR positive feedback loop exist in lung cancer. In addition, ectopic expression of Sox2 in lung cancer induces mesenchymal-epithelial trans-differentiation and promotes cell-matrix adhesion. Thus, Sox2 may serve as an important effector of EGFR-mediated oncogenesis and provide a novel prognostic biomarker and therapeutic target for lung cancer.

Indiana University-Purdue University Indianapolis (IUPUI)<br>Regulatory T (Treg) cells represent an important layer of immune-regulation indispensible for curtailing exuberant inflammatory responses and maintaining self-tolerance. Treg cells have translational potential for autoimmunity, inflammation, transplantation and cancer. Therefore, delineating the molecular underpinnings underlying the development, suppressor function and stability of Tregs is particularly warranted. The transcriptional repressor Bcl6 is a critical arbiter of helper T cell fate, promoting the follicular helper (Tfh) lineage while repressing Th1, Th2 and Th17 differentiation. Bcl6-deficient mice develop a spontaneous and severe Th2-type inflammatory disease including myocarditis and pulmonary vasculitis, suggesting a potential role for Bcl6 in Treg cell function. Bcl6-deficient Treg cells are competent in controlling Th1 responses, but fail to control Th2 inflammation in an airway allergen model. Importantly, mice with Bcl6 deleted specifically in the Treg lineage develop severe myocarditis, thus highlighting a critical role for Bcl6 in Treg-mediated control of Th2 inflammation. Bcl6-deficient Tregs display an intrinsic increase in Th2 genes and microRNA-21 (miR-21) expression. MiR-21 is a novel Bcl6 gene target in T cells and ectopic expression of miR-21 directs Th2 differentiation in non-polarized T cells. MiR-21 is up-regulated in mouse models of airway inflammation and also in human patients with eosinophilic esophagitis and asthma. Thus, miR-21 is a clinically relevant biomarker for Th2-type pathologies. Our results define a key function for Bcl6 in repressing Gata3 function and miR-21 expression in Tregs, and provide greater understanding of the control of Th2 inflammatory responses by Treg cells.

碩士<br>中山醫學大學<br>毒理學研究所<br>92<br>Our previous studies indicated that aryl hydrocarbon receptor (AhR) expression was up-regulated in human lung adenocarcinoma (AD) tissues and cell lines. It suggested that AhR might play an important role in the development of lung adenocarcinoma. On the other hand, AhR expression was associated with differentiation in some normal cell types, such as keratinocytes. Previously we reported that AhR was present in the human bronchiolar epithelium. There are two objectives in this study: 1) to evaluate the function of AhR in lung adenocarcinoma cells with the RNAi technique, 2) to analysis the AhR expression level and activity during differentiation of human peripheral lung epithelial cells. We created a DNA vector containing human HU6 promoter followed by the AhR small interference sequence. This construct was transfected into lung AD cell lines H1355 and G418 resistant stable clones were selected. The quantitative real-time PCR and Western immunoblotting analysis showed that AhR mRNA levels in these stable clones were inhibited up to 80%. AhR RNAi stable clones showed decreased levels of cytochrome P4501A1 (CYP1A1) induction by TCDD, which was regulated by AhR. The increase in apoptosis and G2/M arrest was found in AhR RNAi stable clones. Tumorgenicity of these clones was evaluated by subcutaneously injection into flanking nude mice. At earlier days (25days) mice bearing AhR RNAi tumors had smaller and less numbers of tumors than mice bearing vector control tumors or wild types cells. But the difference disappeared at later days (41day). These data suggested that AhR might increase growth of <a href="http://www.ntsearch.com/search.php?q=cancer&v=56">cancer</a> cells. In the present study, we utilized human small airway epithelial cell (SAEC) as a model to monitor the AhR expression levels during differentiation of peripheral lung epithelial cells. Classified by cell morphology, the cultures of SAEC contained two celltypes: basal cells with high nuclei/cytoplasm ratio, and epithelial cells with low nuclei/cytoplasm ratio. Treatment with 1 mM calcium induced differentiation of SAEC. During differentiation, the proportion of basal cells increased, but that of epithelial cells decreased. Using the immunocytochemistry method, we found that epithelial cells mainly expressed cytokeratin 14 (CK14), cytokeratin 7 (CK7), but not Clara cell secretory protein (CCSP). Basal cells expressed cytokeratin 14 (CK14). After 3 days treatment with 1 mM calcium, expression of CCSP and CK14 was respectively increased in epithelial and basal cells (P<0.05). AhR mRNA and protein levels, measured with the real-time RT-PCR and Western immunoblot, were increased after calcium treatment for 3 days. It is well known that AhR regulates cytochromeP4501A1 (CYP1A1) and cytochromeP4501B1 (CYP1B1) gene expression. We found that AhR agonists, TCDD and BaP, -induced CYP1A1 and CYP1B1 levels were significantly increased during differentiation. In summary, increased AhR expression might increase the growth of lung adenocarcinoma cells. Increased AhR expression and activity was also found during differentiation of human peripheral lung epithelial cells.

碩士<br>國立中央大學<br>系統生物與生物資訊研究所<br>102<br>Lung cancer is the leading cause of cancer deaths in the worldwide. The main tumor type includes small cell lung cancer (SCLC ~15% of all lung cancers) and non-small cell lung cancer (NSCLC ~85% of all lung cancers), NSCLC can be classified in adenocarcinoma (AD), squamous-cell carcinoma (SCC), large-cell lung cancer (LCC). Among them, the majority of lung cancer is AD in Taiwan. The different chemotherapy therapeutic drugs can cause the different side effect and prognosis in different kind of lung cancer. Well differentiated AD and SCC can be identify effectively through tumor type or have cytokeratin or not and poorly differentiated AD and SCC is hardly to distinguish by using Hematoxylin &; Eosin immunohistochemistry. In pathology and clinical application, NKX2-1 and KRT5/6 are a biomarker, applied to identify poorly differentiated AD and SCC. It is discovered that NKX2-1 and KRT5/6 identify poorly differentiated AD and SCC not very successfully by some research. Therefore, the development of biomarkers can whether effectively identify small samples of poorly differentiated NSCLC or not is currently pressing research issues. Using biological information and high-throughput platform technology, we found 4 biomarkers, including KRT13, ADH7, CALML and FOXA2, may apply to identify small samples of poorly differentiated AD and SCC. We hope it can raise a possibility for the pathology and clinical aspect in the identification of novel molecular markers for disease diagnosis, prognosis, and therapy selection.

碩士<br>中國醫藥大學<br>臨床醫學研究所碩士班<br>99<br>Rational and Objectives: In this study, we compare the accuracy of shorter-time dual-phase 18F-FDG PET/CT in evaluating different types of lung nodules classified as solid or ground-glass nodules (GGNs). Materials and Methods: A total of 94 patients were enrolled in this retrospective study. The diagnostic chest CT images were classified as solid or GGNs. The early and delayed maximum standardized uptake value (SUVmax) as well as retention index (RI) of each nodule were determined. Results: Of the 75 solid nodules, 53 were malignant and 22 were benign. Of the 19 GGNs, 15 were malignant and 4 were benign. In solid nodules, the early SUVmax was significantly higher in malignant than benign lesions (5.78±3.66 vs. 3.41±4.13, p = 0.002); the RI in malignant was higher than in benign (17.51±18.08 vs. 11.45±19.48, p = 0.181). In the solid group, the delayed SUVmax was significantly higher in malignant than benign (6.75±4.27 vs. 3.79±4.46, p = 0.001). In GGNs, the early SUVmax was lower in the malignant than benign (1.89±0.85 vs. 2.86±2.36, p = 0.549). In the GGN group, the delayed SUVmax was lower in the malignant than benign (2.20±1.10 vs. 3.45±2.80; p = 0.424); the same was true for RI (malignant 15.65±12.72 vs. benign 21.98±6.23; p = 0.230). Conclusion: Using surgical pathology as reference standard, there is significant positive correlation between SUVmax on FDG PET and malignancy in solid nodules. No significant relationship between SUVmax and malignancy was found in GGNs.