| Rape pollen is rich in polysaccharides, peptides, flavonoids and long-chain fatty acids and other substances. It has a variety of physiological activity, such as to improve the immune capacity, resistance to radiation damage, prevention and treatment of prostate disease. At present, rape pollen anti-tumor study concentrated on pollen polysaccharide instead of focusing on up to 30% of another active ingredient --- polypeptide. We have studied the optimum extraction of Peptides from Rape Pollen Glutelines(PRPG) and proved PRPG has obvious antioxidant activity and anti-tumor in vitro. Based on the previous research results,this paper want to detect the effect of PRPG on apoptosis of the human gastric cancer cell SGC7901,and the related mechanism of it.1、Gastric cancer SGC7901 cells were challenged with PRPG(10-7、10-6、10-5、 10-4g/mL)、with 5-fluorouracil (5-FU,10-6g/mL) or sterile water in vitro. WST-1 assay, cell counting assay were used to examine the effect of PRPG on growth in SGC7901 cell line. The results exhibited that, compared with the control group, PRPG groups cells were significantly less (P<0.01), suggested that PRPG could inhibit the proliferation of SGC7901 cells, and in a dose-dependent manner.2、Using flow cytometry, Annexin V-FITC/PI double staining and PI staining to detecte the influence of LABP on apoptosis and cell cycle in SGC7901 cell line respectively. Annexin V-FITC/PI double staining result showed that, compared with the control group, the apoptosis rate of PRPG group was significantly increased (P<0.05). PI staining result showed that, the percentage of cells in G1 phase of PRPG group was significantly increased, demonstrationed that PRPG could increased the cells in Gl phase and arrest cell cycle.3、Western Blot method was used to detect the protein level expression of apoptotic relation molecular,cell cycle relation molecular and Ras-Raf-MAPK pathway relation molecular. The results confirmed that, the protein expression of Caspase3 and Caspase9 had significantly increased compared with the control group (P<0.05), the protein expressions of Cyclin A, Cyclin D1 and Cyclin E were dramatically down-regulated (P<0.05). Besides, the PRPG can also significantly down-regulated the expression of p-ERK and Ras protein in the Ras-Raf-MAPK pathway, indicated that maybe the mechanisms of anti-tumor activity of PRPG went through the Ras-Raf-MAPK pathway.4、From The Effect of PRPG mediated by ER-a36 on SGC7901 cell line,we found that, PRPG could inhibit the growth of SGC7901. The expression of ER-α36 and CyclinDl both reduced comparing with the control group and showed a concentration-dependent manner. By treating cells with high concentrations of E2β, the proliferation ability and expression of ER-a36 and CyclinDl were decreased. The finding of cells treated with low concentration of E2β is the opposite. Difference between the two groups was statistically significant. PRPG has biological activity, which effect is similar to high concentrations E2β. Both of them could inhibit the proliferation of gastric cancer cell line SGC7901. The effect of PRPG in gastric cancer may be mediated through ER-α36. |
PDF Full Text Request