Expression Of AP-2in Gastric Cancer And Influence Of DADS On Human Gastric Cancer Cell AP-2

Objective:AP-2（activating protein-2）, as an important transcription factor family, isclosely related to tumor formation and growth. Expression of AP-2family moleculesin human gastric cancer and its relationship with the biological behaviors such asgastric cancer proliferation, invasion and metastasis is unclear. By detecting AP-2expression in gastric cancer tissues, this study explores the possible correlationbetween AP-2molecule expression and the clinical progression of gastric cancer; thisstudy also explores the influence of DADS on the AP-2expression of human gastriccancer MGC803cells.Methods:1. Using tissue microarray to detect AP-2α, AP-2β and AP-2γ expression ingastric cancer tissues, and observing the relationship between AP2expression andtumor differentiation, metastasis, and clinical;2. Having Western-Blot, RT-PCR, and immunocytochemistry analysis ofDADS’s influence on the AP-2α, AP-2β and AP-2γ expression of human gastriccancer MGC803cells.Results:1. Tissue microarray showed that expression of AP-2α, AP-2β and AP-2γ proteinin gastric cancer is mainly distributed in the cytoplasm. AP-2α, AP-2β and AP-2γexpression in gastric cancer is higher than normal gastric epithelial cells. In acomparison between normal gastric mucosa and adjacent noncancerous tissues andgastric cancer tissues, the difference was statistically significant （P <0.05）. Inaddition, the expression level of the three types of tissues in gastric cancer tissues isrelated to lymph node metastasis （P <0.05）.2. RT-PCR results showed that MGC803cells are processed in30mg L-1 DADS for4h,12h, and24h, and they are also processed in10mg L^-1,20mg L^-1,and30mg L^-1 DADS. Compared with the control group, the mRNA level of AP-2α,β, and γ of cells and gastric cancer-related genesMMP-9, VEGF, EGFR, MMP-2, andMMP-7is not significantly decreased （P <0.05）. That means DADS does not affectthe mRNA level of AP-2α, AP-2β and AP-2γ.3. Western-Blot results showed that after processing MGC803cells in30mg L^-1 DADS for4h,12h, and24h, the total protein expression level of AP-2α, AP-2βand AP-2γ is not changed significantly, and the increase of nuclear protein levels ofAP-2α, AP-2β, and AP-2γ reduced （P <0.05）. That means that DADS could reduceAP-2α, AP-2β and AP-2γ nucleoprotein expression of human gastric cancer cells,which showed a significant time–effect dependency （P <0.05）.4. Immunocytochemistry results showed that after processing of MGC803cellsin30mg L^-1 DADS for24hours, the AP-2α, AP-2β and AP-2γ expression in thecytoplasm and nucleus expression reduced. That means that DADS significantlysuppresses AP-2expression of human gastric cancer cells.Conclusion:1. In gastric cancer tissues, AP-2α, AP-2β, and AP-2γ expression level is related tolymph node metastasis.2. DADS reduce AP-2α, AP-2β and AP-2γ expression in gastric cancer cellnucleus.