The Isolation, Identification And The Stemness Characteristics Of Gastric Cancer Stem Cells

Background:Gastric cancer is the most common malignant tumor of digestive tract with the high mortality rate,and seriously affects people’s physical and mental health. Its pathogenesis is still unclear.Cancer stem cells had become a hot topic in cancer research, and may play an important role in the occurrence of gastric cancer. Separation of suspension culture was an important method of gastric cancer stem cell research.Aims:To study the isolation and identification of Gastric cancer stem cells (GCSCs) and evaluate its sternness characteristics.Methods:GCSCs were enriched through spheroid body formation by cultivating the human gasrtric cancer cell lines in serum-free medium containing EGF and bFGF. The ability of the tumor spheres formation was analyzed by the colony forming experiment. Gastric cancer stem cells were identificated by immunofluorescent staining. The wound healing and transwell assays were performed to evaluate the effects of the migration and invasion of GCSCs. Growth inhibition in response to chemotherapeutic drugs was evaluated by the cell viability assay.Results:Compared with parental gastric cancer cells, the tumor spheres in GCSCs were richer and had the stronger colony forming ability. The higher expression of CD44 and CD54 was detected in the tumor spheres of the GCSCs, but the lower expression of HK-ATPase. The migration of GCSCs stronger than parental gastric cancer cells group through the experiment of the wound healing and transwell, the results were significant difference(P<0.05).Transwell chamber in vitro invasion experiment assay the number of cell invasion in the GCSCs group increased than the parental gastric cancer cells group, the results were significant difference(P<0.05). The cell viability assay showed that the IC50 of tumor spheres of GCSCs to cisplatin was significantly enhanced compared to the parental gastric cancer cells(P<0.01).Conclusions:Tumor spheres rich in GCSCs have higher self-renewing capacity, multilineage differentiation potency, higher ability to migration and invasion, more resistant ability to cisplatin.