Isolation And Identification Of Side Population Cells In Human Gastric Cancer

Objective:To compare the proliferation, migration, cloning and tumor-bearing among fourhuman gastric cancer cell lines respectively in vitro, and isolate, identify the sidepopulation(SP) cells from gastric cancer cell lines such as AGS, BGC-823, SGC-7901orMKN-28.Methods:Human gastric cancer cell lines, include AGS, BGC-823, SGC-7901and MKN-28,were cultured. The ability of proliferation was measured with cell growth curves andpopulation doubling time calculated through direct cells counting, as well as with the flatcolony formation. Cell migration was assessed by Boyden cell migration assay. Colonyformation in soft agarose and athymic nude mice model were performed to analyzecolony characters. Gastric cancer cell lines were cultivated in serum-free medium and SPcells reforming into floating spheres were isolated. Four human gastric cancer cell lineswith different differentiation grades, were stained by fluorochrome Hoechst33342andCFSE, and SP cells were detected by fluorescence microscopy.Results:Comparing with AGS and BGC-823, the cellular growth rates of SGC-7901andMKN-28were slower significantly(P<0.05), among other groups showed no significantdifference(P>0.05); The number of colony formation in the flat plate declined from AGS,BGC-823, SGC-7901to MKN-28; Boyden cell migration assay showed the cell migrationability of AGS and BGC-823was higher than that in SGC-7901and MKN-28(P<0.05).AGS cells formed a small clones or tumor in soft agar and nude mice subcutaneous, whilethe other three cell lines formed larger ones. In the absence of serum, SP cells in gastriccancer cells survived, proliferated and assembled into the suspended tumor cell spheresbeside AGS cell. SP cells were detected in three of the four gastric cancer cell lines, but no one in AGS.Conclutions:The ability of proliferation and migration is decreasing from AGS, BGC-823, andSGC-7901to MKN-28. All of cell lines form larger clones or tumor beside AGS cell. SPcells could be isolated and detected in the most of gastric cancer cell lines.