ZEB1 coordinately regulates laminin-332 and {beta}4 integrin expression altering the invasive phenotype of prostate cancer cells.
Metastasis involves the invasion of cancer cells across both the extracellular matrix and cellular barriers, and an evolving theme is that epithelial-to-mesenchymal transition (EMT) may mediate invasive cellular behavior. Previously, we isolated and analyzed a subpopulation of PC-3 prostate cancer cells, TEM4-18, and found that these cells both invaded an endothelial barrier more efficiently and exhibited enhanced metastatic colonization in vivo. Transendothelial migration of these cells depended on expression of ZEB1, a known regulator of EMT. Surprisingly, these cells were much less invasive than parental PC-3 cells in assays that involve matrix barriers. Here, we report that TEM4-18 cells express significantly reduced levels of two subunits of laminin-332 (β3 and γ2) and that exogenous laminin-332, or co-culture with laminin-332-expressing cells, rescues the in vitro invasion phenotype in these cells. Stable knockdown of ZEB1 in prostate cancer cells up-regulated LAMC2 and ITGB4 mRNA and protein and resulted in a concomitant increase in Transwell migration. Using chromatin immunoprecipitation (ChIP), we show that ZEB1 directly interacts with the promoters of LAMC2 and ITGB4. These results provide a novel molecular basis for reduced laminin-332 observed in clinical prostate cancer specimens and demonstrate a context-dependent role for EMT in invasive cellular behavior.
Drake
Justin M
JM
Departments of Molecular Physiology and Biophysics, Roy J and Lucille ACarver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
Barnes
J Matthew
JM
Madsen
Joshua M
JM
Domann
Frederick E
FE
Stipp
Christopher S
CS
Henry
Michael D
MD
D045744:Cell Line, Tumor; D002465:Cell Movement; D002843:Chromatin / Q000378:metabolism; D018920:Coculture Techniques; D004847:Epithelial Cells / Q000166:cytology; D005109:Extracellular Matrix / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D039663:Integrin beta4 / Q000378:metabolism*; D007797:Laminin / Q000737:chemistry*; D008297:Male; D009362:Neoplasm Metastasis; D010641:Phenotype; D011471:Prostatic Neoplasms / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D000071799:Zinc Finger E-box-Binding Homeobox 1
D002843:Chromatin; D018398:Homeodomain Proteins; D039663:Integrin beta4; D007797:Laminin; D014157:Transcription Factors; C486307:ZEB1 protein, human; D000071799:Zinc Finger E-box-Binding Homeobox 1