Mutated epithelial cadherin is associated with increased tumorigenicity and loss of adhesion and of responsiveness to the motogenic trefoil factor 2 in colon carcinoma cells.
Epithelial (E)-cadherin and its associated cytoplasmic proteins (alpha-, beta-, and gamma-catenins) are important mediators of epithelial cell-cell adhesion and intracellular signaling. Much evidence exists suggesting a tumor/invasion suppressor role for E-cadherin, and loss of expression, as well as mutations, has been described in a number of epithelial cancers. To investigate whether E-cadherin gene (CDH1) mutations occur in colorectal cancer, we screened 49 human colon carcinoma cell lines from 43 patients by single-strand conformation polymorphism (SSCP) analysis and direct sequencing. In addition to silent changes, polymorphisms, and intronic variants in a number of the cell lines, we detected frameshift single-base deletions in repeat regions of exon 3 (codons 120 and 126) causing premature truncations at codon 216 in four replication-error-positive (RER+) cell lines (LS174T, HCT116, GP2d, and GP5d) derived from 3 patients. In LS174T such a mutation inevitably contributes to its lack of E-cadherin protein expression and function. Transfection of full-length E-cadherin cDNA into LS174T cells enhanced intercellular adhesion, induced differentiation, retarded proliferation, inhibited tumorigenicity, and restored responsiveness to the migratory effects induced by the motogenic trefoil factor 2 (human spasmolytic polypeptide). These results indicate that, although inactivating E-cadherin mutations occur relatively infrequently in colorectal cancer cell lines overall (3/43 = 7%), they are more common in cells with an RER+ phenotype (3/10 = 30%) and may contribute to the dysfunction of the E-cadherin-catenin-mediated adhesion/signaling system commonly seen in these tumors. These results also indicate that normal E-cadherin-mediated cell adhesion can restore the ability of colonic tumor cells to respond to trefoil factor 2.
Cancer and Immunogenetics Laboratory, Imperial Cancer Research Fund, Institute of Molecular Medicine, John Radcliffe Hospital, Oxford OX3 9DS, United Kingdom.
J A
JA
Efstathiou
D
D
Liu
J M
JM
Wheeler
H C
HC
Kim
N E
NE
Beck
M
M
Ilyas
A J
AJ
Karayiannakis
N J
NJ
Mortensen
W
W
Kmiot
R J
RJ
Playford
M
M
Pignatelli
W F
WF
Bodmer
D000818:Animals; D020029:Base Pairing; D015820:Cadherins / Q000235:genetics* / Q000502:physiology; D002448:Cell Adhesion / Q000187:drug effects; D003110:Colonic Neoplasms / Q000235:genetics* / Q000473:pathology*; D015179:Colorectal Neoplasms; D004261:DNA Replication / Q000235:genetics; D005091:Exons; D005260:Female; D016368:Frameshift Mutation; D014644:Genetic Variation; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D007438:Introns; D051379:Mice; D008819:Mice, Nude; D009077:Mucins; D009124:Muscle Proteins; D009154:Mutation; D009479:Neuropeptides; D010455:Peptides / Q000494:pharmacology*; D017354:Point Mutation; D011110:Polymorphism, Genetic; D018807:Polymorphism, Single-Stranded Conformational; D011994:Recombinant Proteins / Q000096:biosynthesis; D017384:Sequence Deletion; D014162:Transfection; D014183:Transplantation, Heterologous; D000071164:Trefoil Factor-2; D000071165:Trefoil Factor-3; D014407:Tumor Cells, Cultured
D015820:Cadherins; D006133:Growth Substances; D009077:Mucins; D009124:Muscle Proteins; D009479:Neuropeptides; D010455:Peptides; D011994:Recombinant Proteins; C000604007:TFF2 protein, human; C099037:TFF3 protein, rat; C000604008:Tff2 protein, rat; D000071164:Trefoil Factor-2; D000071165:Trefoil Factor-3