Expression And Role Of Oncogene DJ-1 In Gastric Cancer Stem Cell

Aim: To study the expression and role of oncogene DJ-1 on gastric cancer stem cells(GCSC). Methods: Detecting the expression of DJ-1 in GCSC by RT-PCR.Then DJ-1 was cloned from the normal gastric cell lines and construct the recombinant plasmid with expression vector which was packaged by lentiviruses.Infecting recombinant plasmid to the gastric cancer MGC-803 and screening overexpression DJ-1 and the interference expression DJ-1 in GCSC. Detecting the expression of DJ-1 mRNA and proteins in stable transfected gastric spheres and compared with control group. The survival and growth of gastric cancer stem cells was assessed by MTS assay, and then depict cell growth curve of GCSC. The tumor sphere culture method was employed to detect the self-renewal and proliferation ability of GCSC. Results:(1) MGC-803 cell lines has the most highly expression of DJ-1.(2) In GCSC,the expression of DJ-1 was higher than inherent MGC-803 cell.(3) The expression of DJ-1 mRNA and proteins was decreased in sphere pLV-DJ-1, while they were opposited in sphere siDJ-1.(4) The proliferation was increased in sphere pLV-DJ-1, while opposite in sphere si DJ-1.(5)The proliferation and renewal rate was increased and capacity of tumorigenic was enhenced in pLV-DJ-1, tumorigenic rate of pLV-DJ-1 to MGC803 was 30.53%±0.82% vs 15.8%±0.52%, P<0.001. While in cell siDJ-1, the tumorigenic rate of siDJ-1 to con was 7.80%±0.37% vs 15.50%±0.63%, P<0.05. Conclusion: The DJ-1 gene is highly expressed in gastric cancer stem cells, and can promote the ability of proliferation and renewal in gastric cancer cell lines. DJ-1 may be a potentialcell surface markers of gastric cancer stem cells and targeting killing gastric cancer stem cells may provide a new way for the diagnosis and treatment of gastric cancer.