microRNA-218 suppresses the proliferation, invasion and promotes apoptosis of pancreatic cancer cells by targeting HMGB1

Objective： To detect the expression profiles of micro RNA-218（mi R-218） in human pancreatic cancer tissue（PCT） and cells and their effects on the biological features of human pancreatic cancer cell line PANC-1 and observe the effect of mi R-218 on the expression of the target gene high mobility group box 1（HMGB1）, with an attempt to provide new treatment methods and strategies for pancreatic cancer.Methods： The expressions of mi R-218 in PCT and normal pancreas tissue as well as in various pancreatic cancer cell lines including As PC-1, Bx PC-3, and PANC-1 were determined with quantitative real-time reverse transcription polymerase chain reaction（q RT-PCR）. The change of mi R-218 expression in PANC-1 cells was detected using qR T-PCT after the transfection of miR-218 mimic for 48 h. Cell Counting Kit-8（CCK-8） was applied for detecting the effect of mi R-218 on the activity of PANC-1 cells. The effects of mi R-218 on the proliferation and apoptosis of PANC-1 cells were analyzed using the flow cytometry. The effect of mi R-218 on the migration of PANC-1 cells was detected using the Trans-well migration assay. The HMGB1 was found to be a target gene of mi R-218 by luciferase reporter assay, and the effect of mi R-218 on the expression of HMGB1 protein in cells were determined using Western blotting.Results： As shown by q RT-PCR, the expressions of mi R-218 in PCT and in pancreatic cancer cell line significantly decreased when compared with the normal pancreatic tissue（NPT）（P〈0.01）. Compared with the control group, the miR-218 expression significantly increased in the PANC-1 group after the transfection of mi R-218 mimic for 48 h（P〈0.01）. Growth curve showed that the cell viability significantly dropped after the overexpression of mi R-218 in the PANC-1 cells for two days（P〈0.05）. Flow cytometry showed that the S-phase fraction significantly dropped after the overexpression of mi R-218（P〈0.01） and the percentage of apoptotic cells significantly increased（P〈0.01）. As shown by the Trans-well migration assay, the enhanced mi R-218 expression was associated with a significantly lower number of cells that passed through a Transwell chamber（P〈0.01）. Luciferase reporter assay showed that, compared with the control group, the relative luciferase activity significantly decreased in the mi R-218 mimic group（P〈0.01）. As shown by the Western blotting, compared with the control group, the HMGB1 protein expression significantly decreased in the PANC-1 group after the transfection of mi R-218 mimic for 48 h（P〈0.01）.Conclusions： The mi R-218 expression decreases in human PCT and cell lines. mi R-218 can negatively regulate the HMGB1 protein expression and inhibit the proliferation and invasion of pancreatic cancer cells. A treatment strategy by enhancing the mi R-218 expression may benefit the patients with pancreatic cancer.

microRNA-218 promotes gemcitabine sensitivity in human pancreatic cancer cells by regulating HMGB1 expression

Objective： The purpose of this study was to examine the effect of gemcitabine（GEM） on micro RNA-218（mi R-218） expression in human pancreatic cancer cells.Methods： Quantitative reverse transcription polymerase chain reaction（q RT-PCR） was performed to examine the differences in mi R-218 expression between the GEM-sensitive Bx PC-3 pancreatic cancer cells and GEM-resistant PANC-1 cells. The effect of GEM on the expression of mi R-218 in PANC-1 cells was also investigated. PANC-1 cells were transfected either with HMGB1 si RNA to knock down the expression of HMGB1 or with the recombinant HMGB1 expression vector（pc DNA3.1-HMGB1） to overexpress HMGB1. The effect of ectopic expression of HMGB1 on the apoptosis of mi R-218-transfected and GEMtreated PANC-1 cells was examined by flow cytometric analysis.Results： The mi R-218 expression level was lower in GEM-resistant PANC-1 cells compared to GEMsensitive Bx PC-3 cells（P〈0.05）. The percentage of apoptotic PANC-1 cells was significantly increased in the mi R-218 mimic ＋ GEM group compared to the mimic ctrl ＋ GEM group and the normal control group（P〈0.01）. The HMGB1 expression level was markedly decreased in PANC-1 cells transfected with HMGB1 si RNA but was significantly increased in PANC-1 cells transfected with the recombinant HMGB1 expression vector, pc DNA3.1-HMGB1（P〈0.01）. The proportion of apoptotic PANC-1 cells was significantly lower in the mi R-218 mimic ＋ GEM ＋ pc DNA3.1-HMGB1 group compared to the mi R-218 mimic ＋ GEM ＋ HMGB1 si RNA group（P〈0.01）.Conclusions： The expression level of mi R-218 was downregulated in the GEM-resistant cell line. mi R-218 promoted the sensitivity of PANC-1 cells to GEM, which was achieved mainly through regulating the expression of HMGB1 in PANC-1 cells.

The current surgical treatment of pancreatic neuroendocrine neoplasms in China: a national wide cross-sectional study

Objective:The aim of this study is to investigate the current status of the diagnosis and treatment of patients with pancreatic neuroendocrine neoplasms(pNENs)undergoing surgery in China.Methods:This is a multicenter cross-sectional study performed in China.Data from patients with pNENs undergoing surgery at 33 high-volume medical centers,where the number of pancreatectomies exceeds 20 cases per year,were collected and analyzed between March 1,2016 and February 28,2017.Results:In total,392 patients with pNENs were enrolled.The male to female ratio was 1.4.The majority of patients were aged between 40 and 70 years.65.6%of the patients had non-functional tumors.Among those with functional tumors,the percentages of insulinomas,gastrinomas,glucagonomas,and vasoactive intestinal peptide-secreting tumors were 94.8%,1.5%,2.2%,and 1.5%,respectively.Multidisciplinary team(MDT)discussion was conducted for 39.0%of the patients.Minimally invasive surgery was performed on 31.1%of the 392 patients.The incidence of grade B/C pancreatic fistula formation was 4.4%.A total of 89.0%of the surgeries achieved R0 resection,and 41.6%of the tumors were well differentiated.Lymph node metastasis was present in 8.9%of the patients.The percentages of patients with grades G1,G2,and G3 disease were 49.2%,45.7%,and 5.1%,respectively.Conclusion:This multicenter cross-sectional study systematically presents the current status of the diagnosis and treatment of patients with pNENs undergoing surgery in China.MDT consultation for pNENs has not been widely implemented in China.Although the incidence of surgical complications is relatively low,minimally invasive procedures should be further promoted.This study shows us how to improve the outcomes of these patients.

The current surgical treatment of pancreatic cancer in China: a national wide cross-sectional study

Objective: The aim of this study is to investigate the current status of pancreatic cancer patients undoing surgical treatment in China and to find ways to improve the survival of these patients in the future. Methods: This study is a national, multicenter, cross-sectional study in China. Information regarding pancreatic cancer patients undergoing surgical treatment from 34 high-volume tertiary IIIA level hospitals was collected and analyzed from the March 1, 2016 to the February 28, 2017. Results: In total, 2200 pancreatic cancer patients were enrolled from 34 tertiary IIIA level hospitals in 16 provinces across China. The male-to-female ratio was 1.5. More than 80% of the patients were between 50 and 70 years old. The top 4 symptoms were epigastric discomfort, abdominal pain, jaundice, and weight loss. Carbohydrate antigen 19-9 and carcinoembryonic antigen were elevated in 70.9% and 27.1% of patients, respectively. A multidisciplinary team (MDT) discussion was carried out for 35.0% of patients before surgery. The proportion of minimally invasive pancreatic surgeries was approximately 20%. A total of 83.4% of the operations achieved R0 resection, and the incidence of grade 3/4 postoperative complications was 7.7%. Only 13.4% of the patients received postoperative adjuvant chemotherapy. The percentage of pathological stage I tumors was only 24.5%. Conclusion: The majority of pancreatic cancer patients undergoing surgical resection in China are in an advanced stage. The MDT consultations for pancreatic cancer have not been widely carried out. R0 resection has been achieved in most cases, with relatively low incidence of serious complications, but minimally invasive pancreatic surgery should be further promoted. The application of postoperative chemotherapy remains low. This national, multicentre, cross-sectional study comprehensively presents the current status of pancreatic cancer patients undergoing surgical treatment and shows the road to improve survival of these patients in the future.