Enhanced motility of KGF-transfected breast cancer cells.
BACKGROUND
In a previous study, we reported that keratinocyte growth factor (KGF) produced a rapid increase in the motility of ER-positive breast cancer cells. Others have demonstrated that KGF treatment in rodent species produces rapid mammary ductal hyperplasia. Epithelial cells do not produce KGF; thus, in the present study, MCF-7 cells were stably transfected with a KGF-expressing vector and the motility and morphology of the transfected, non-transfected and empty vector cell lines compared.


METHODS
A mammalian expression vector containing a KGF cDNA was transfected into MCF-7/beta cells, and two stable clones (MCF-7/beta/KGF-T8 and MCF-7/beta/KGF-T9) were identified. Western blotting of conditioned medium from these clones was used to confirm the expression of KGF. The motility of wild-type and KGF-transfected MCF-7 cells was compared using time-lapse videomicroscopy and a cell culture wounding model which examined cell migration over a period of 1-3 days.


RESULTS
The Western blots demonstrated that the expression of KGF in both the MCF-7/beta/KGF-T8 and MCF-7/beta/KGF-T9 cell lines was higher than the wild-type and MCF-7/beta cell lines. The cell proliferation and migration distance was significantly greater for both KGF-transfected MCF-7 cell lines than the wild-type and MCF-7/beta cell lines under the same experimental conditions. Further, changes in motile morphology were observed in both the MCF-7/beta/KGF-T8 and MCF-7/beta/KGF-T9 cell lines. In addition, the MCF-7/beta/KGF-T8 clone was found to produce much larger tumors than both the MCF-7/beta/KGF-T9 and EV clones in mouse xenografts. These results indicated that autocrine production of KGF in the KGF-transfected MCF-7 cell lines enhanced cell migration, migration-related morphology and xenograft tumor growth.


CONCLUSIONS
KGF-transfected MCF-7 cells displayed a much greater motility than non-transfected cells, confirming the KGF motility enhancement effect which we previously reported. The use of KGF-transfected breast cancer cells in the xenograft model may help to study the mechanism of KGF-mediated cell motility and to identify specific KGF antagonists that may be used to prevent or impede KGF-mediated metastatic progression.
Zang
Xiao-Ping
XP
Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center and InterGenetics Incorporated, Oklahoma City, OK 73117, USA.
Bullen
Elizabeth C
EC
Manjeshwar
Sharmila
S
Jupe
Eldon R
ER
Howard
Eric W
EW
Pento
J Thomas
JT
D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology*; D051523:Fibroblast Growth Factor 7 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D014162:Transfection; D014183:Transplantation, Heterologous
D051523:Fibroblast Growth Factor 7