title: Sustained delivery of siRNA/PEI complex from in situ forming hydrogels potently inhibits the proliferation of gastric cancer.
abstract: BACKGROUND
  Gastric cancer remains a major cause of mortality and morbidity worldwide. In recent years, gene-based therapeutic strategies were confirmed promising in cancer inhibition and attracted great attention. RNA interference (RNAi) is a powerful tool for gene therapy and has been widely employed to aid in treatment for various diseases, especially cancers. However, effective delivery of small interfering RNA (siRNA) to target cells in vivo remains a challenge for that it is prone to degradation and only lasts a few days in rapidly dividing cells.
  
  
  METHODS
  Due to its biocompatibility and well-established safety profile, collagen represents a favourable matrix for in-site drug delivery. In the study, collagen hydrogel was used as carriers to test the feasibility of localized and sustained delivery of Id1-targeted siRNA for in vivo gastric cancer inhibition. To enhance the siRNA delivery, cationic polyethylenimine (PEI) was further emplored for scallold modification. The efficacy of siRNA delivery and cancer inhibition were evaluated with multimodality of mehods in vitro and in vivo.
  
  
  RESULTS
  Our results showed that addition of polyethylenimine (PEI) to collagen can facilitate entry of Id1-siRNA into target cells, prolong the silencing effect, and further inhibit tumor growth both in vitro and in vivo.
  
  
  CONCLUSIONS
  This collagen-based delivery system may facilitate the pathogenesis elucidation and design of effective therapies against gastric cancer.
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China. penghao009@sina.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Peng
authors.affiliation: The Affiliated Tumor Hospital of Guangxi Medical University, Nanning, 530021, Guangxi Zhuang Autonomous Region, China.
authors.forename: Huawei
authors.initials: H
authors.lastname: Yang
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Liwei
authors.initials: L
authors.lastname: Song
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Jinwen
authors.initials: J
authors.lastname: Sun
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Du
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Keyu
authors.initials: K
authors.lastname: Lu
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Yin
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Xu
authors.affiliation: Beijing Meitan General Hospital, 29 South of Xi ba river, Chaoyang District, Beijing, 100028, China.
authors.forename: Shidong
authors.initials: S
authors.lastname: Wei
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D020100:Hydrogels / Q000008:administration & dosage / Q000737:chemistry; D051798:Inhibitor of Differentiation Protein 1 / Q000037:antagonists & inhibitors*; D051379:Mice; D008819:Mice, Nude; D011094:Polyethyleneimine / Q000737:chemistry; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000494:pharmacology; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000235:genetics; D023041:Xenograft Model Antitumor Assays
chemical_list: D020100:Hydrogels; C497453:ID1 protein, human; D051798:Inhibitor of Differentiation Protein 1; D034741:RNA, Small Interfering; D011094:Polyethyleneimine
keywords: Collagen hydrogel; Gastric cancer; Id1; siRNA