Abstract: Abstract: Objective To study the influence of exogenous EGFP labeling on biological behavior of tumor Cells in vitro . Methods Using liposome transfection and lentivirus infection respectively, exogenous EGFP carried by different vectors was expressed in different tumor cell lines. Stable exogenous EGFP expressing cell lines were selected for further analysis. The growth was measured by MTT assay. The distribution of cell size was tested by Cell Counter（CasyTT）. The invasion was measured by Boyden-chamber assay. Results Stably-expressing of exogenous EGFP human colon cancer cell line HCT116-GFP, HCT116-EGFP, COLO 320DM-EGFP and murine dendritic cell sarcoma cell line DG6-EGFP was successfully established. After expression of exogenous EGFP, the growth of HCT116-GFP cells was similar to that of HCT116 cells, while the growth of HCT116-EGFP cells, COLO320DM- EGFP cells and DG6-EGFPcells was significantly decreased. After expression of exogenous EGFP, the cell volume of HCT116-EGFP cells was bigger than that that of HCT116 cells, the cell volume of DG6-EGFP cells was similar to that of DG6 cells. After expression of exogenous EGFP, the invasion of HCT116-EGFPcells was significantly lower than that of HCT116 cells, the invasion of DG6-EGFP cells was similar to that of DG6 cells. Conclusion Exogenous EGFP labeling of tumor cells may or may not affect the biological characteristics of the tumor cells in vitro, indicating that before the use of these models, researchers should evaluate its effects on the relevant parameters.

Key words: EGFP, tumor, cell lines, proliferation, invasion