ObjectiveTo detect the expressions of CD133 in four gastric cancer cell lines (KATO-Ⅲ, SGC7901, AGS, and MKN-45) and investigate the different biological characteristics of CD133 positive (CD133+) cells and CD133 negative (CD133-) cells in the KATO-Ⅲ cell lines. MethodsThe CD133 gene and protein expressions of four gastric cancer cell lines were evaluated by semiquantitative RT-PCR and Western blot, respectively. CD133+ cells in KATO-Ⅲ cell lines were isolated by magnetic activated cell sorting (MACS) and examined in morphology, growth characteristics, proliferation, and differentiation in vitro. The sensitivity of different concentrations (0.05, 0.10, 0.20, 0.50, and 1.00 mg/ml) 5-fluoropyrimidinedione (5-FU) were contrasted by drug sensitivity testing in vitro (Cell Counting Kit 8-assay) between CD133+ cells and CD133- cells. ResultsThe expressions of CD133 gene and protein in the KATO-Ⅲ cell lines were significantly higher than those in the other three cell lines (Plt;0.05). CD133+ cells produced spheroid colonies in serum-free medium culture and were ber abilities of proliferation and differentiation than those of CD133- cells in vitro. The inhibitor rate of the CD133+ cells at concentration of 0.50 mg/ml was lower than that of CD133- cells (Plt;0.05). ConclusionsCell population with CD133+ in the KATO-Ⅲ cell lines have b ability of cloning, better capability of proliferation and differentiation, as well as anticancer drug resistance to 5-FU. CD133 can be applied as one of surface markers for the detection to gastric cancer initiator cells.
Objective To study the expression of CD133 mRNA in peripheral blood mononuclear cells （PBMCs） of patients with gastric adenocarcinoma （GC） before operation or after operation and its clinical significance. To learn the relationship of CD133 expressions in PBMCs to primary lesion of GC. Methods Fifty patients with GC，10 patients with gastric ulcer （GU）， and 10 healthy volunteers were registered in this research. Expressions of CD133 mRNA in PBMCs and in primary lesion of GC by semi-quantitative RT-PCR and expression of CD133 protein in primary lesion of GC by immunohistochemical staining were detected. Correlations of CD133 mRNA expression with clinicopathologic parameters and postoperative survival rate were analyzed. Relation between CD133 mRNA level and CD133 protein expression or lymphatic metastasis were assessed too. Results The brightness scale value （ABSV） of CD133 mRNA in PBMCs of the patients with GC before operation （0.270±0.163） was higher than that in the healthy volunteers （0.029±0.060） or in the patients with GU （0.059±0.099） （P=0.000）. The ABSV of CD133 mRNA in the PBMCs of patients with GC before operation was related to poor cell differentiation （P=0.002）， lymph vessel invasion （P=0.028），deeper tumor invasion （P=0.041），later lymph node metastasis stage （P=0.010），later TNM stage （P=0.006），and positive expression of CD133 protein in the primary lesion （P=0.011）. Relative analysis revealed that the ABSV of CD133 mRNA in the PBMCs of patients with GC before operation was related positively to metastatic lymphatic nodes ratio （rs=0.422，P=0.002），metastatic lymph node number （rs=0.398，P=0.004），and ABSV of CD133 mRNA in the primary lesion of GC （rs=0.337，P=0.017）. The ABSV of CD133 mRNA in the PBMCs of patients with GC after operation obtained from blood sample at 1 week after curative resection was higher than that in the patients before operation （P=0.021）. Patients suffered from deeper invasion inclined to have a higher ABSV of CD133 mRNA after surgery （P=0.039）. Higher expression of CD133 mRNA in patients after operation demonstrated a much poorer survival rate （P=0.013）. Conclusions Higher expressive level of CD133 mRNA in GC before operation is associated to poor cell differentiation，lymph vessel invasion，deeper invasion，higher lymph node metastasis，later TNM stage，and positive expression of CD133 protein. It is also related positively to metastatic lymphatic nodes ratio，metastatic lymph node number，and ABSV of CD133 mRNA in primary lesion of GC. The level of CD133 mRNA in PBMCs of patients with GC is higher after operation as compared with before operation，which demonstrates deeper invasion and poorer survival.