Study On The Role Of Endoplasmic Reticulum Stress In Cisplatin Resistant Of Ovarian Cancer

ObjectiveThe study intends to investigate the effect and machanism endoplasmic reticulum stress in augmenting sensitivity of cisplatin in ovarian carcinoma,to obverse the new way for effective reversal agent of DDP resistance in ovarian cancer in clinical.MethodsWestern Blot was used to test the expression of GRP78protein in SKOV3cells and SKOV3/DDP cells, and the expression of GRP78protein in SKOV3cells with saquinavir of different doses. The effects of different drugs to expression of mTOR、 Beclinl were detected by RT-PCR and Western Blot in SKOV3cells. MTT assay was used to analyze IC50value of DDP in SKOV3cells, the effect of saquinavir about sensitivity of cisplatin in ovarian carcinoma at different dosage. When autophagy was inhibited by3-MA, MTT assay was used to analyze the effect of saquinavir to augment sensitivity of cisplatin in ovarian carcinoma.Results1. The GRP78protein was both expressed in SKOV3and SKOV3/DDP cells. The expression were different(t=5.304, P=0.006), and there were significant difference between two groups(P<0.05). Compared with SKOV3cells, the expression of GRP78protein increased28.58%in SKOV3/DDP cells.2. The expression of GRP78protein in SKOV3cells increased along with the saquinavir concentration. The cells were divided into four groups, which were saquinavir10μmol/1、saquinavir20μmol/1、saquinavir40μmol/1and control group. Compared with control group, the expression of GRP78protein in saquinavir10μmol/1、saquinavir20μmol/1、saquinavir40μmol/1groups were increased23.48%、35.39%、41.46%, the expression of GRP78protein in four groups were different(F=136.791,P=0.000),there were significant difference between four groups(P<0.05).3. Saquinavir could decrease the sensitivity of cisplatin in SKOV3cells. The IC50of SKOV3cells was5.49μg/ml. After interferenceed by Saquinavair lOμmol/1、 Saquinavair20μmol/l, The IC50of SKOV3cells were11.199μg/ml、14.906μg/ml.The sensitivities of SKOV3cells to DDP decreased1.04times、1.72times.4. The cells were divided into five groups, which were control group、Saquinavair group、LY294002group、DDP group、Saquinavair+DDP group. The expression of mTOR mRNA in SKOV3cells was Saquinavair+DDP group> Saquinavair group> LY294002group> DDP group> control group. The expression of mTORmRNA in five groups were different(F=613.061,P=0.000),there were significant difference between five groups(P<0.05). At the same time, The expression of Beclinl mRNA in SKOV3cells was Saquinavair+DDP group> Saquinavair group> LY294002group> DDP group> control group. The expression of Beclinl mRNA in five groups were different(F=4002.353, P=0.000),there were significant difference between five groups(P<0.05).5. The cells were divided into five groups, which were control group、Saquinavair group、LY294002group、DDP group、Saquinavair+DDP group. The expression of mTOR protein in SKOV3cells was Saquinavair+DDP group> Saquinavair group> LY294002group> DDP group> control group.The expression of mTOR protein in five groups were different(F=42.959,P=0.000),there were significant difference between five groups(P<0.05). At the same time, the expression of Beclinl protein in SKOV3cells was Saquinavair+DDP group> Saquinavair group> LY294002group> DDP group> control group. The expression of Beclinl protein in five groups were different(F=105.629, P=0.000),there were significant difference between five groups(P<0.05).6. Saquinavir could increase the sensitivity of cisplatin in SKOV3when3-MA added.When3-MA inhibited the autophagy, DDP’s IC50of Saquinavair10、 Saquinavir20decreased to11.199μg/ml、14.906μg/ml.Conclusions1.Induced-endoplasmic reticulum stress can decrease the the sensitivity of cisplatin in SKOV3 2. Endoplasmic reticulum stress could up-regulate autophagy through the mTOR and Beclinl pathways, leading to decrease the sensitivity of cisplatin in SKOV3. Inhibition of autophagy could increase the sensitivity of cisplatin in SKOV3cells. Autophagy could be the target to improve therapeutic effect in chemetherapg and to deteriorate drug resistance in tumor.