| Gastric cancer is a common malignancy worldwide, accounts for the forth most common malignant tumors and the first two of the total cancer death rate. In our country,the incidence and mortality of gastric cancer account for the first 1 and 3 respectly. Medicines for the treatment of gastric cancer emerging in the short term showed good clinical efficacy. However, large-scale follow-up show that long-term survival of cancer patients has not increased significantly as the use of chemotherapy and serious side effects of some chemotherapy drugs limit their clinical application. Low-dose and multi-drug combinatioand is an important cancer drug research direction.All-trans retinoic acid (all-trans retinoic acid, ATRA) is the major metabolite of vitamin A,and is essential to maintain growth and development.It is a recognized differentiation inducer. Oxaliplatin (Oxaliplatin, L-OHP) is the third generation platinum anti-cancer compounds, mainly used for advanced colorectal cancer. It has no cross-resistance with the first generation cisplatin and the second generation carboplatin and its good tolerance, low toxicity, therefore it is recognized.Whether ATRA combined with L-OHP used in gastric cancer can increase efficacy has currently not reported. In this study, we observe the induction of apoptosis of retinoic acid (ATRA) comibined with oxaliplatin (L-OHP) in human gastric cancer BGC-823 cells in vitro observation of cellular, thus provide a theoretical basis for further study.1. Treat BGC-823 cells with ATRA,L-OHP respectively and then combined, observe the morphologieal changes of BGC-823 cells by inverted microscope.2. Assesse the proliferative inhibition rate of BGC-823 cells after treated with ATRA and L-OHP respectively for 24h,48h,72h by MTT assay.3. Analyze the changes of apoptosis rate and cell cycle of BGC-823 cells after treated with ATRA and L-OHP for 48h by flow cytometry(FCM).4. Detect the expressions of Bcl-2 and Survivin protein of BGC-823 cells after treated with ATRA and L-OHP for 48h by immunohistochemistry method.1.24h after treated with drugs, cell gaps widened, intracellular granules increased and became vacuoles.48h later,most of cells floated in the culture medium and few cells still shew adherent growth. The nucleus in some cells were pyknosis and broken.The nuclear membrane disappeard but the cell membrane kept integrity and grew apophysises.All of the changes shew the advanced stage of apoptotisis.72h later, the number of apoptotic cells increased.Compared with the control group,more cells became debris and the number of adherent cells reduced significantly in experimental groups.2. The proliferative inhibition effect of the cells treated with ATRA shew time dependence and the effect was not obvious at 24h.48h and 72h later,the effect was relatively obvious.Compared with the control group,the difference was statistically significant(P<0.05).The inhibition effect was more significant in the combined group. The best time of action was 48h.Compared with the ATRA group and L-OHP group,the difference was statistically significant(P<0.05). 3.48h after treated with ATRA, the rate of G0/G1 and G2/M phase cellls increased and the rate of S phase decreased. After treated with L-OHP, the rate of G0/G1 phase declined, while phase S and G2/M increased.In the combined group, the rate of G0/G1 phase and G2/M phase cells increased and S phase decreased. The differences of the apoptosis rate among the three groups was statistically significant(P<0.05).4. Among the four groups,the expression of Survivin protein and Bcl-2 protein in cytoplasm were the most in the control group and the least in the combined group.The differences of the positive rate among the four groups was statistically significant (P<0.05).1. ATRA could inhibit the proliferation of human gastric cancer BGC-823 cells and the effect shew time dependence.The best results appeared at 48h. Associated with L-OHP, the proliferative inhibition effect of the cells reinforced.2. ATRA could induce the differentiation of human gastric cancer BGC-823 cells and arouse G0/G1 phase arrest.L-OHP could promote cell apoptosis and arouse G2/M phase and S phase arrest.The effect of inducing apoptosis were enhanced when ATRA and L-OHP were combined.3. ATRA and L-OHP could induce the apoptosis of human gastric cancer BGC-823 cells and the probable mechanism might be related to the down regulation of the expression of Bcl-2 and Survivin protein.
|
PDF Full Text Request