TY - JOUR
T1 - Epithelial to Mesenchymal Transition Is Impaired in Colon Cancer Cells With Microsatellite Instability
AU - Pino, Maria S.
AU - Kikuchi, Hirotoshi
AU - Zeng, Min
AU - Herraiz, Maria Teresa
AU - Sperduti, Isabella
AU - Berger, David
AU - Park, Do Youn
AU - Iafrate, A. John
AU - Zukerberg, Lawrence R.
AU - Chung, Daniel C.
PY - 2010/4
Y1 - 2010/4
N2 - Background & Aims: Colorectal cancers (CRCs) displaying DNA microsatellite instability (MSI) are associated with a favorable natural history, but the molecular basis for this observation has not been defined. We sought to determine whether the epithelial to mesenchymal transition (EMT) is impaired in MSI-positive CRCs that characteristically have a mutant transforming growth factor-β receptor type II (TGFBR2) gene. Methods: The induction of EMT by transforming growth factor-β1 (TGF-β1) was analyzed by phase contrast microscopy, immunofluorescence, quantitative reverse transcription polymerase chain reaction, immunoblotting, and cellular migration, and invasion assays. Expression of EMT markers was evaluated by immunohistochemistry and quantitative reverse transcription polymerase chain reaction in a series of human colorectal tumors. Results: TGF-β1 induced changes in cellular morphology, gene expression, motility, and invasion consistent with EMT in microsatellite stable (MSS) colon cancer cells, whereas cells with MSI and mutant TGFBR2 were unresponsive to TGF-β1. These effects did not require Smad4, but depended on the recruitment of extracellular signal-regulated kinase. Tumor cells with MSI but wild-type TGFBR2 underwent EMT in response to TGF-β1, indicating that TGFBR2 genotype is a key determinant of the EMT response in tumors with MSI. In human colorectal tumors, expression of EMT markers was significantly associated with adverse clinicopathologic features and the absence of MSI. Conclusions: These findings define a unique genotype-phenotype relationship between TGFBR2 and EMT that may contribute to the improved prognosis consistently observed in colon cancers with MSI.
AB - Background & Aims: Colorectal cancers (CRCs) displaying DNA microsatellite instability (MSI) are associated with a favorable natural history, but the molecular basis for this observation has not been defined. We sought to determine whether the epithelial to mesenchymal transition (EMT) is impaired in MSI-positive CRCs that characteristically have a mutant transforming growth factor-β receptor type II (TGFBR2) gene. Methods: The induction of EMT by transforming growth factor-β1 (TGF-β1) was analyzed by phase contrast microscopy, immunofluorescence, quantitative reverse transcription polymerase chain reaction, immunoblotting, and cellular migration, and invasion assays. Expression of EMT markers was evaluated by immunohistochemistry and quantitative reverse transcription polymerase chain reaction in a series of human colorectal tumors. Results: TGF-β1 induced changes in cellular morphology, gene expression, motility, and invasion consistent with EMT in microsatellite stable (MSS) colon cancer cells, whereas cells with MSI and mutant TGFBR2 were unresponsive to TGF-β1. These effects did not require Smad4, but depended on the recruitment of extracellular signal-regulated kinase. Tumor cells with MSI but wild-type TGFBR2 underwent EMT in response to TGF-β1, indicating that TGFBR2 genotype is a key determinant of the EMT response in tumors with MSI. In human colorectal tumors, expression of EMT markers was significantly associated with adverse clinicopathologic features and the absence of MSI. Conclusions: These findings define a unique genotype-phenotype relationship between TGFBR2 and EMT that may contribute to the improved prognosis consistently observed in colon cancers with MSI.
KW - Colorectal Cancer
KW - Epithelial to Mesenchymal Transition
KW - Microsatellite Instability
KW - Transforming Growth Factor-β Receptor Type II
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U2 - 10.1053/j.gastro.2009.12.010
DO - 10.1053/j.gastro.2009.12.010
M3 - Article
C2 - 20026115
AN - SCOPUS:77949845438
VL - 138
SP - 1406
EP - 1417
JO - Gastroenterology
JF - Gastroenterology
SN - 0016-5085
IS - 4
ER -