ABSTRACT
Objective: To investigate the effects of extracellular domain-truncated mutant of hepaCAM gene on biological behaviors of bladder carcinoma cells in vitro. Methods: Human cell line T24 was transfected with pEGFP-N2-hepaCAM, pEGFP-N2-hepa CAM-mt or mock plasmid pEGFP-N2 by lipofectamine mediation. The stable colonies were obtained by G418 screening. Laser confacal microscopy was used to detect the location of hepaCAM-mt in the T24 cells, Western blotting was used to determine the expression of protein in stable cells. Cell adhesion and motility abilities were tested by cell adhesion and detachment assays and wound healing and Matrigel invasion assays. The proliferation ability was investigated by MTT assay. Results: In well-spread cells, mutant proteins were localized on the perinuclear membrane like wild-type hepaCAM protein; after the cells contacted with each other, hepaCAM-mt protein had non-specific expression in the cells, which was significantly different with the localization of the hepaCAM proteins. T24 cell clone which acquired stable expression of hepaCAM-mt protein had decreased adhesion and motility abilities and enhanced proliferation potential compared with the cells with wild-type hepaCAM gene expression. Conclusion: The deletion of extracellular domain in hepaCAM gene was important for the localization of hepaCAM protein but had no significant effect on the proliferation, adhesion, and migration of T24 cells. The extracellular domain of hepaCAM was necessary for exerting normal functions of hepaCAM gene.