Grape Seed Proanthocyanidin Extract Inhibits Pancreatic Cancer Cell Progression Through Regulation Of MiR-27a And Let-7a

Background and Objective: Pancreatic cancer(PC) is one of the most common malignances in digestive system and with an overall 5-year survival rate of <5%. There is an upward trend in morbidity and mortality of PC as a result of its rapid dissemination and resistance to conventional chemotherapy and radiotherapy. Multiple studies have shown that grape seed proanthocyanidin extract(GSPE) plays an important role in anti-tumor activity through. regulation of cell signal transduction pathways. GSPE was found to inhibit tumorigensis via regulation of micro RNAs. Therefore,in-depth investigation of the molecular mechanism of GSPE mediated in antitumor function is required.which could provide theoretical and experimental basis in the treatment of pancreatic cancer. The purpose of this study(1) We investigated the effects of GSPE on cell proliferation, migration and apoptosis in pancreatic cancer cells.(2)To determine whether GSPE could down-regulate mi R-27 a, leading to the inhibition of cell growth,migration and induction of apoptosis in pancreatic cancer cells.(3) To explore whether a GSPE could up-regulare let-7a, resulting in the inhibition of cell growth and migration, and induction of apoptosis in pancreatic cancer cells. and subsequently exerting its anti-tumor functions.Methods:1. We investigated the effect of GSPE on cell growth, migration, and apoptosis by MTT assay. Transwell matrigel and Annexin V-FITC/PI assay. and Wound-healing assay, expecially in As PC-1 cell lines.2. mi R-27 a and let-7a expressions were examined by Real-time mi RNA reverse transcriptase-PCR assay after treatment with GSPE.3. To detect the function of mi R-27 a and let-7a in tumor, we used the transient transfection of mi R-27 a inhibitor to down-regulate mi R-27 a. We also used let-7a mimics to up-regulate let-7a in pancreatic cancer cells and combine with GSPE to treat with cells. The expression of FOXO1 protein was measured by western blot.Results:1. Compared with the control group, we found GSPE could inhibit human pancreatic cancer cell proliferation, retard the migration and invasion ability, induce cell apoptosis. GSPE exerts its inhibitory effect on pancreatic cancer cell As PC-1 in a dose-dependent manner(P<0.05). Determined by MTT-assay. We observed the IC50 of GSPE in As PC-1 cells was 75μg/ml,We used the IC50 in the subsequent experiments for testing the ability of GSPE in As PC-1 cells.2. GSPE could down-regulation the expression of mi R-27 a in As PC-1 cells. After with GSPE for 48 h,the q RT-PCR results showed GSPE treatment group significantly decreased the expression of mi R-27 a in As PC-1 cells compared with the control group(P<0.05).Moreover down-regulation of mi R-27 a inhibiteds tumor cell growth, invasion, migration ability. and promoted apoptosis, In addition. we found that GSPE upregulated FOXO1 expression via down-regulation of mi R-27 a.3. GSPE could up-expression of let-7a. The q RT-PCR results showed GSPE treatment group increased the expression of let-7a in As PC-1(P<0.05). We also found GSPE inhibit pancreatic cancer cell proliferation. invasion, migration capacity. and promoted apoptosis partly through up-regulation of let-7a.Conclusion:1.GSPE could inhibit cell growth and, migration, and induce apoptosis in As PC-1 pancreatic cancer cells.2. GSPE decreased the expression of mi R-27 a and subsequently up-regulation of FOXO1 level, leading to inhibiton of cell growth and, migration, and, induction of apoptosis in AsPC-1 cells.3. Our results demonstrated that GSPE inhibited cell proliferation and migration and promoted apoptosis partlythrough up-expression of let-7a in As PC-1 cells.