Overexpression of pp60c-src elicits invasive behavior in rat colon epithelial cells.
OBJECTIVE
Src activation is reported as an early event found in preneoplastic colonic adenomas and in 70% of colon carcinomas. The aim of this study was to identify the biological consequences of c-src overexpression in rat colon epithelial cells.


METHODS
Introduction and overexpression of c-src in an immortalized rat colon epithelial cell line was achieved using lipofection. Transfectants were tested for changes in growth and cell behavior using different in vitro assay systems.


RESULTS
Colon epithelial cells overexpressing c-src showed the ability to form microcolonies in soft agar without acquiring tumorigenic potential. In in vitro assays, c-src transfectants displayed a gain of invasive potential through Matrigel without an accompanying change in migrational ability. No discernible qualitative changes were observed in the phosphotyrosyl protein profile between c-src and v-src transfectants. Assessment of the cadherin/catenin status in these cells revealed an intact, functional complex with no detectable tyrosine phosphorylation of different components of the complex.


CONCLUSIONS
Overexpression of c-src in an immortalized rat colon epithelial cell line does not elicit full neoplastic transformation but enhances anchorage-independent growth and confers invasion capability. Increased invasion through Matrigel was not linked to inactivation of the cadherin complex in c-src transfectants.
Pories
S E
SE
Laboratory of Cancer Biology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
Hess
D T
DT
Swenson
K
K
Lotz
M
M
Moussa
R
R
Steele
G
G
Shibata
D
D
Rieger-Christ
K M
KM
Summerhayes
C
C
D000818:Animals; D015820:Cadherins / Q000378:metabolism / Q000502:physiology; D002461:Cell Line, Transformed / Q000502:physiology; D002465:Cell Movement; D003106:Colon / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D009361:Neoplasm Invasiveness / Q000503:physiopathology; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism*; D051381:Rats; D014162:Transfection
D015820:Cadherins; D016392:Proto-Oncogene Proteins pp60(c-src)