Endoscopic Treatment For Walled-off Pancreatic Necrosis And Study On Translation Initiation Sites Of Rnd3

Background: Walled-off pancreatic necrosis is one of the late local complications of acute necrotizing pancreatitis with a high occurrence rate of 1-9%.After 4 weeks of the pathogenesis of acute necrotizing pancreatitis,the pancreatic or peripancreatic necrosis tissue form capsule wall without epithelial tissue,than walled-off necrosis can be diagnosed.The traditional treatment for WON is surgical treatment,while the complication rate and mortality rate are high.The EUS-guided drainage of walled-off pancreatic necrosis has been considered the first-line treatment modality as a minimally invasive alternative to surgical drainage.This is due to the ability of the EUS to assess the wall thickness,identify major vessels and find the closest access to the fluid cavity.The procedure will create an internal fistula between fluid collections and the gastric or duodenal lumen,a transmural stent or a nasocystic catheter is then deployed within necrotic collection to facilitate drainage,which avoid the inconvenience of an external drainage and the risk of cutaneous fistula.However,the effectiveness of EUS-guided drainage was unsatisfactory in last decades.The poor ability of drainage of solid necrotic debris resulting in long-time unmanageable infection is the bottleneck of this therapeutic method.We reported our experience that EUS-guided drainage combined with cyclic irrigation(EDCCI)would be useful in overcoming these difficulties.Methods and results: 18 patients with symptomatic walled-off pancreatic necrosis who underwent EUS-guided drainage combined with cyclic irrigation in Shanghai First People’s Hospital,China from January 2010 to May 2015 were recruited into this retrospective study.Walled-off pancreatic necrosis was defined as a poorly demarcated area,which may be sterile or infected [10].The walled-off pancreatic necrosis suitable for EUS-guided drainage met these criteria:(1)>5 cm in size and the lesion located adjacent to the stomach or duodenum(2)ongoing infection which could not be controlled by antibiotics(3)clinical symptoms such as abdominal pain,fever,gastric outlet obstruction or obstructive jaundice[10,11].The exclusion criteria were patients with the walled-off pancreatic necrosis located more than 1.5cm from the GI lumen or those with coagulopathy.17 of 18 patients underwent EUS-guided drainage combined with cyclic irrigation technology(EDCCI).Surgical treatment was instead performed in 1 patient due to intolerance of endoscopic operation.The walled-off pancreatic necrosis of 16 patients undergone EDCCI were completely vanished after treatment;no abscess recurrence was observed.At a median of 258 days’ follow-up,all 16 patients who had successful outcomes were doing well without recurrence.The effective rate of EUS-guided drainage combined with cyclic irrigation technology(EDCCI)was up to 94.12%(16 in 17).Conclusions: Endoscopic ultrasonography-guided drainage combined with cyclic irrigation is an effective treatment option for symptomatic walled-off pancreatic necrosis to facilitate drainage and obviate the need for subsequent surgery or endoscopic necrosectomy.Background: Rnd3 is a small G protein in member of the Rnd subfamily of Rho family.Due to the lack of GTP enzyme activity,Rnd3 protein only exists one state as GTP combined state.This is different from other small G proteins act as molecular switch.Rnd3 can participate in a variety of cell activities in the body,with complex biological functions,such as regulating actin stress fiber,thus affecting the morphology,cytoskeleton reorganization,cell differentiation,transfer,and the progress of the cell cycle.Rnd3 also plays an important role in the occurrence and development of cancers,mainly influencing tumor differentiation,proliferation and migration.However,about the role of Rnd3 in cancer development,there are many contradictions in the existing researches.Studies have found that in the stomach cancer,primary liver cancer,lung cancer,prostate cancer and colon cancer,Rnd3 showed a trend of lower expressing,prompt that Rnd3 may play a role of tumor suppressor gene.But studies have also found that Rnd3 is highly expressed in human pancreatic cancer and melanoma,thus can play a role of oncogene.In our experiments,we found that Rnd3 generated two kinds of protein subtypes from two different translation initiation sites,predicting the function of these two Rnd3 protein subtypes may exist different functions.Perhaps it is the cause of the contradiction between the roles of Rnd3 in tumor diseases.Methods and results: Build mutant Rnd3 overexpression plasmid for eukaryotic cells,transfecting human embryo kidney cells.Extracting total cell protein after 48 hours,use western blot method to detect the corresponding protein expression of mutated plasmid and identify the corresponding protein translation initiation site.Establishing mutated Rnd3 and wild-type Rnd3 stably expressed SGC – 7901 cell lines,test different Rnd3 protein subtypes’ effects on gastric cancer cell proliferation and migration.Conclusions: Rnd3 m RNA exists two different translation initiation sites,producing two kinds of protein subtypes by selective translation,and each subtype plays a different role in the proliferation and migration of SGC-7901 gastric cancer cells.