Identification Of Differently Expressed Genes In LTEP-A-2s And HUVECs Under Different Culture Conditions

Backgroud & ObjectiveAngiogenesis is necessary for solid tumor growth and dissemination. Tumor's survive depends on the interaction between tumor cells and endothelial cells. But whether the interaction will cause genetic changes in those cells as well? In the present study we use a in vitro co-culture model of human umbilical vein endothelial cells (HUVEC) and lung cancer cells LTEP-A-2 to mimic the real microenvironment in vivo,where the two kinds of cells have reciprocal interactions. We used the cDNA gene chip to screen the differentially expressed genes in co-culture model compared with monoculture model. Then we verify the results of the gene chip by real time-PCR and analysis their biological functions. The result of this study can provide theoretical support and experimental basis for further research on mechanism of tumor angiogenesis.Methods:1. A in vitro co-culture model of human umbilical vein endothelial cells (HUVEC) and lung cancer cells LTEP-A-2 was established.2. Amount of cell proliferation in co-culture model and monoculture model was compared by counting living cells and MTT colorimetry.3. Sorting HUVEC from lung cancer cell LTEP-A-2 by flow cytometer.4. cDNA gene chip was used to screen the differentially expressed genes in co-culture model compared with monoculture model and verified the results of the gene chip by real time-PCR.Results:1.1588 differential expression genes were definited in co-cultured HUVEC, among them there were 1176 genes up-ragulated and 382 genes down-ragulated.1442 differential expression genes were definited in co-cultured LTEP-A-2, among them there were 762 genes up-ragulated and 680 genes down-ragulated.2. Analysis of KEGG pathway showed that genes in 6 signaling pathways:P53,MAPK,VEGF,TGF-beta,Jak-STAT and PPAR, expressed differentially.3.6 differentially expressed genes were selected to be amplificated, and the expression of them was coinsident with the microarray.Conclusions:1. A in vitro co-culture model of human umbilical vein endothelial cells and lung cancer cells was established,the differential expression genes were selected by gene chip which may be associated with angiogenesis in lung cancer.2.6 signaling pathways:P53,MAPK,VEGF,TGF-beta,Jak-STAT and PPAR,had the most closed biological significance associated with angiogenesis in lung cancer.3.It was confirmed that results of realtime-PCR were consistent with the gene chips.