Genome-wide microarray expression and genomic alterations by array-CGH analysis in neuroblastoma stem-like cells.
Neuroblastoma has a very diverse clinical behaviour: from spontaneous regression to a very aggressive malignant progression and resistance to chemotherapy. This heterogeneous clinical behaviour might be due to the existence of Cancer Stem Cells (CSC), a subpopulation within the tumor with stem-like cell properties: a significant proliferation capacity, a unique self-renewal capacity, and therefore, a higher ability to form new tumors. We enriched the CSC-like cell population content of two commercial neuroblastoma cell lines by the use of conditioned cell culture media for neurospheres, and compared genomic gains and losses and genome expression by array-CGH and microarray analysis, respectively (in CSC-like versus standard tumor cells culture). Despite the array-CGH did not show significant differences between standard and CSC-like in both analyzed cell lines, the microarray expression analysis highlighted some of the most relevant biological processes and molecular functions that might be responsible for the CSC-like phenotype. Some signalling pathways detected seem to be involved in self-renewal of normal tissues (Wnt, Notch, Hh and TGF-β) and contribute to CSC phenotype. We focused on the aberrant activation of TGF-β and Hh signalling pathways, confirming the inhibition of repressors of TGF-β pathway, as SMAD6 and SMAD7 by RT-qPCR. The analysis of the Sonic Hedgehog pathway showed overexpression of PTCH1, GLI1 and SMO. We found overexpression of CD133 and CD15 in SIMA neurospheres, confirming that this cell line was particularly enriched in stem-like cells. This work shows a cross-talk among different pathways in neuroblastoma and its importance in CSC-like cells.
Department of Biochemistry and Genetics, University of Navarra School of Sciences, Pamplona, Spain.
Raquel
R
Ordóñez
Department of Biochemistry and Genetics, University of Navarra School of Sciences, Pamplona, Spain.
Gabriel
G
Gallo-Oller
Department of Biochemistry and Genetics, University of Navarra School of Sciences, Pamplona, Spain.
Soledad
S
Martínez-Soto
Department of Biochemistry and Genetics, University of Navarra School of Sciences, Pamplona, Spain.
Sheila
S
Legarra
Institut Gustave Roussy, Villejuif, France.
Noémie
N
Pata-Merci
Institut Gustave Roussy, Villejuif, France.
Justine
J
Guegan
Institut Gustave Roussy, Villejuif, France.
Giselle
G
Danglot
Institut Gustave Roussy, Villejuif, France.
Alain
A
Bernheim
Molecular Pathology Research Unit, Department of Pathology, Virgen de la Salud Hospital, Toledo, Spain.
Bárbara
B
Meléndez
IdiPaz Research Unit, La Paz University Hospital, Madrid, Spain.
Juan A
JA
Rey
Department of Biochemistry and Genetics, University of Navarra School of Sciences, Pamplona, Spain.
Javier S
JS
Castresana
D045744:Cell Line, Tumor; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D055106:Genome-Wide Association Study; D006801:Humans; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D009447:Neuroblastoma / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D015398:Signal Transduction / Q000235:genetics*
D009363:Neoplasm Proteins