Abstract:

Objective To observe the effect of NRP-1b1／b2 IgG monoclonal antibody （NRP-1mAb） on the growth of gastric cancer cell BGC-823， and to explore the possible mechanism of the antibody. Methods NRP-1mAb was prepared in laboratory， and the purity of antibody was detected by SDS-PAGE. Gastric cancer BGC-823 cells were cultured by 0， 25， 100， 200， 400 μg／ml NRP-1 mAb. The morphological changes of BGC-823 cells were observed by microscope. The proliferation， colony formation and apoptosis of gastric cancer BGC-823 cells were observed by MTT assay， colony forming assay and flow cytometry. The phosphorylation of related signal proteins was detected by Western blotting analysis. Results SDS-PAGE test showed that the purity of NRP-1mAb was above 95％. Microscopy showed apoptotic changes of BGC-823 cells treated by NRP-1mAb. MTT assay showed that NRP-1mAb could inhibit the proliferation of BGC-823 cells in a time and dose dependent manner（P＜0.01）. Colony forming assay showed that different doses of NRP1mAb could inhibit the colony formation of BGC-823 cells in a dose dependent manner（P＜0.01）. Flow cytometry showed that different doses of NRP-1mAb could promote the apoptosis of BGC-823 cells mainly at early apoptosis stage. It was found that the level of Akt phosphorylation was decreased after treated by NRP-1mAb， and there was no significant phosphorylation of ERK， p38 and JNK protein. Conclusion NRP-1mAb can inhibit the growth of gastric cancer cell BGC-823 and promote apoptosis， which may be related to the inhibition of Akt phosphorylation.