6991
2012
eng
doctoralthesis
1
2012-04-25
--
2012-04-24
Lineage tracing of metastasis in a mouse model for Non-small cell lung cancer (NSCLC)
Untersuchung metastatischer Prozesse durchgenetische Zellmarkierung in einem Mausmodelldes nichtkleinzelligen Lungenkarzinoms (NSCLC)
Non-small cell lung cancer (NSCLC) is the deadliest form of lung cancer and has a poor prognosis due to its high rate of metastasis. Notably, metastasis is one of the leading causes of death among cancer patients. Despite the clinical importance, the cellular and molecular mechanisms that govern the initiation, establishment and progression of metastasis remain unclear. Moreover, knowledge gained on metastatic process was largely based on cultured or in vitro manipulated cells that were reintroduced into immune-compromised recipient mice. In the present study, a spontaneous metastasis mouse model for NSCLC was generated with a heritable fluorescent tag (DsRed) driven by CAG (combination of cytomegalovirus early enhancing element and chicken beta actin) promoter in alveolar type II cells (SpC-rtTA/TetO-Cre/LSL-DsRed). This approach is essential, keeping in mind the reprogramming nature of Myc oncogene (Rapp et al, 2009). Such genetic lineage tracing approach not only allowed us to monitor molecular and cellular changes during development of primary tumor but also led us to identify the different stages of secondary tumor development in distant organs. Upon combined expression of oncogenic C Raf-BXB and c-Myc (MYC-BXB-DsRed) in lung alveolar type II epithelial cells, macroscopic lung tumors arose comprising of both cuboidal and columnal cellular features. C Raf-BXB induced tumors (CRAF-DsRed) exhibit cuboidal morphology and is non-metastatic whereas Myc-BXB induced lung tumors (Myc-BXB-DsRed) present cuboidal-columnar cellular features and is able to undergo metastasis mainly in liver. Surprisingly, cystic lesions which were negative for SpC (Surfactant protein C) and CCSP (Clara cell secretory protein), strongly expressed DsRed proteins indicating its origin from lung alveolar type II cells. Moreover, early lung progenitor markers such as GATA4 (GATA-binding protein 4) and TTF1 (Thyroid Transcription Factor 1) were still expressed in these early cystic lesions suggesting metastasis as a faulty recapitulation of ontogeny (Rapp et al, 2008). Interestingly, mixed cystic lesions and metastatic tumors contained DsRed and SpC positive cells. These results demonstrate secondary tumor progression from cystic, mixed cystic to malignant transformation. Our results shed tremendous light on reprogramming of metastasizing cells during secondary tumor development. Moreover, such fluorescent tagged metastatic mice model can also be used to track the migration ability of metastatic cancer cell to different organs and its potential to differentiate into other cell types such as blood vessel or stromal cell within the primary tumor.
Das nichtkleinzellige Lungenkarzinom (‚non-small cell lung cancer‘, NSCLC) ist die tödlichste Form des Lungenkrebses mit schlechter Prognose aufgrund hoher Metastasierungsneigung. Metastasierung ist eine der häufigsten Todesursachen bei Krebspatienten. Trotz ihrer klinischen Bedeutung sind die zellulären und molekularen Mechanismen der Entstehung, Etablierung und Progression von Metastasen weiterhin unklar. Darüberhinaus basiert das bisherige Wissen über den Metastasierungsprozess überwiegend auf Zellen, die entweder in vitro kultiviert oder manipuliert und danach in immundefiziente Mäuse rückübertragen wurden.In der vorliegenden Studie wurde ein Mausmodell mit erblichem Fluoreszenzmarker (DsRed) zur spontanen Metastasierung bei NSCLC entwickelt, der durch den CAG-Promotor (‚combination of cytomegalovirus early enhancing element and chicken beta actin‘) in alveolären Typ II-Zellen (SpC-rtTA/TetO-Cre/LSL-DsRed) exprimiert wird. Aufgrund des Reprogrammierungscharakters des Myc-Onkogens war dieser Ansatz essentiell (Rapp et al, 2009). Die Markierung der Zellpopulation auf genetischem Weg erlaubte uns zum einen, die molekularen und zellulären Veränderungen während der Bildung des Primärtumors zu verfolgen, zum anderen konnte so die Entwicklung von Sekundärtumoren unterschiedlicher Stadien in entfernten Organen identifiziert werden. Bei kombinierter Expression von onkogenem C Raf-BXB und c-Myc (MYC-BXB-DsRed) in Lungenalveolar-Epithelzellen vom Typ II entstanden makroskopische Tumore in der Lunge, die auf zellulärer Ebene sowohl kuboidalen als auch kolumnaren Charakter aufwiesen und Metastasen, vorwiegend in der Leber, ausbildeten. Durch C Raf-BXB (CRAF-DsRed) induzierte Tumore erschienen morphologisch als kuboidal ohne Metastasierungsneigung. Überraschenderweise exprimierten zystische Läsionen in der Leber, obwohl negativ für SpC (‚surfactant protein C‘) und CCSP (‚Clara cell secretory protein‘), als Kennzeichen für deren Ursprung aus Lungenalveolarzellen Typ II stark das DsRed-Protein. Darüberhinaus sind in den frühen zystischen Läsionen Marker für frühe Lungenvorläuferzellen wie GATA4 (‚GATA-binding protein 4‘) und TTF1 (‚thyroid transcription factor 1‘) weiterhin exprimiert, was auf den Metastasierungsprozess als gestörte Rekapitulation der Ontogenese hindeutet (Rapp et al, 2008). Metastatische Tumore und Mischformen zu zystischen Läsionen enthielten DsRed- und SpC-positive Zellpopulationen. Diese Ergebnisse weisen in Sekundärtumoren den Übergang von zystischer Läsion zur Mischform mit zystischem Anteil und zur malignen Transformation nach.Unsere Resultate werfen ein neues Licht auf Reprogrammierungsprozesse metastasierender Zellen bei der Bildung von Sekundärtumoren. Das vorgestellte fluoreszenzmarkierte und metastasenbildende Mausmodell kann zum einen zur Untersuchung der Migrationsfähigkeit metastasierender Krebszellen in unterschiedliche Organe verwendet werden. Darüberhinaus ermöglicht dieses Mausmodell die Untersuchung des Differenzierungspotenzials markierter Zellen in andere Zelltypen wie Blutgefäße oder Stromazellen im Primärtumor.
7062
urn:nbn:de:bvb:20-opus-85420
X 124019
Deutsches Urheberrecht
Chitra Thakur
deu
swd
Lungenkrebs
deu
swd
Metastase
deu
uncontrolled
Lungenkrebs
deu
uncontrolled
Metastasierung
eng
uncontrolled
Lung Cancer metastasis
deu
swd
Maus
Biowissenschaften; Biologie
open_access
Graduate School of Life Sciences
Universität Würzburg
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/6991/CHITRA_THAKUR_THESIS_.pdf
13434
2011
eng
1005-1018
11
13
article
1
2016-06-03
--
--
Conditional Expression of Oncogenic C-RAF in Mouse Pulmonary Epithelial Cells Reveals Differential Tumorigenesis and Induction of Autophagy Leading to Tumor Regression
Here we describe a novel conditional mouse lung tumor model for investigation of the pathogenesis of human lung cancer. On the basis of the frequent involvement of the Ras-RAF-MEK-ERK signaling pathway in human non-small cell lung carcinoma (NSCLC), we have explored the target cell availability, reversibility, and cell type specificity of transformation by oncogenic C-RAF. Targeting expression to alveolar type II cells or to Clara cells, the two likely precursors of human NSCLC, revealed differential tumorigenicity between these cells. Whereas expression of oncogenic C-RAF in alveolar type II cells readily induced multifocal macroscopic lung tumors independent of the developmental state, few tumors with type II pneumocytes features and incomplete penetrance were found when targeted to Clara cells. Induced tumors did not progress and were strictly dependent on the initiating oncogene. Deinduction of mice resulted in tumor regression due to autophagy rather than apoptosis. Induction of autophagic cell death in regressing lung tumors suggests the use of autophagy enhancers as a treatment choice for patients with NSCLC.
Neoplasia
10.1593/neo.11652
urn:nbn:de:bvb:20-opus-134347
Neoplasia Volume 13, Issue 11, November 2011, Pages 1005-1018, IN1-IN17
false
true
CC BY-NC-ND: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell, Keine Bearbeitungen 4.0 International
Fatih Ceteci
Jiajia Xu
Semra Ceteci
Emanuele Zanucco
Chitra Thakur
Ulf R. Rapp
eng
uncontrolled
Human lung-cancer
eng
uncontrolled
K-RAS
eng
uncontrolled
Induced senescence
eng
uncontrolled
Gene-expression
eng
uncontrolled
In-vivo
eng
uncontrolled
Kinase pathway
eng
uncontrolled
P53
eng
uncontrolled
Activation
eng
uncontrolled
Model
eng
uncontrolled
Adenocarcinomas
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/13434/028_Ceteci_Neoplasia.pdf
13540
2012
eng
1164–1177
12
14
article
1
2016-06-24
--
--
E-Cadherin Controls Bronchiolar Progenitor Cells and Onset of Preneoplastic Lesions in Mice
Although progenitor cells of the conducting airway have been spatially localized and some insights have been gained regarding their molecular phenotype, relatively little is known about the mechanisms regulating their maintenance, activation, and differentiation. This study investigates the potential roles of E-cadherin in mouse Clara cells, as these cells were shown to represent the progenitor/stem cells of the conducting airways and have been implicated as the cell of origin of human non-small cell lung cancer. Postnatal inactivation of E-cadherin affected Clara cell differentiation and compromised airway regeneration under injury conditions. In steady-state adult lung, overexpression of the dominant negative E-cadherin led to an expansion of the bronchiolar stem cells and decreased differentiation concomitant with canonical Wnt signaling activation. Expansion of the bronchiolar stem cell pool was associated with an incessant proliferation of neuroepithelial body-associated Clara cells that ultimately gave rise to bronchiolar hyperplasia. Despite progressive hyperplasia, only a minority of the mice developed pulmonary solid tumors, suggesting that the loss of E-cadherin function leads to tumor formation when additional mutations are sustained. The present study reveals that E-cadherin plays a critical role in the regulation of proliferation and homeostasis of the epithelial cells lining the conducting airways.
Neoplasia
10.1593/neo.121088
urn:nbn:de:bvb:20-opus-135407
Neoplasia (2012) 14, 1164–1177. DOI 10.1593/neo.121088
Fatih Ceteci
Semra Ceteci
Emanuele Zanucco
Chitra Thakur
Matthias Becker
Nefertiti El-Nikhely
Ludger Fink
Werner Seeger
Rajkumar Savai
Ulf R. Rapp
eng
uncontrolled
injury
eng
uncontrolled
lung cancer
eng
uncontrolled
stem cells
eng
uncontrolled
clara cell
eng
uncontrolled
gene expression
eng
uncontrolled
basal cell
eng
uncontrolled
in vivo
eng
uncontrolled
epithelium
eng
uncontrolled
airway
eng
uncontrolled
renewal
Medizin und Gesundheit
open_access
Institut für Medizinische Strahlenkunde und Zellforschung
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/13540/Ceteci_Neoplasia_2012.pdf