title: Enhancement of gemcitabine sensitivity in pancreatic cancer by co-regulation of dCK and p8 expression.
abstract: The purpose of this study was to improve the gemcitabine sensitivity in pancreatic cancer by adenovirus-mediated co-regulation of dCK and p8 expression. Firstly, we analyzed the sensitivity of three human pancreatic tumor cell lines (Capan-2, Panc-1 and BxPc-3) to gemcitabine using MTT assays, and found Panc-1 to be relatively resistant to gemcitabine. Further, we investigated the expression of dCK and p8 in different pancreatic cancer cell lines using real-time PCR and Western blot analysis, and found that the expression levels of these two genes were related to the gemcitabine sensitivity of pancreatic cancer cells. We constructed recombinant adenovirus vectors, Ad-dCK and Ad-p8-siRNA, that overexpressed dCK and knocked down p8, respectively. Using MTT assays, we observed that combined infection using Ad-dCK and Ad-p8-siRNA in vitro led to a significant decrease in the gemcitabine IC50 with an increase in apoptosis and caspase-3 activity in Panc-1 cells, which are relatively resistant to gemcitabine. Furthermore, in established subcutaneous pancreatic cancer models in nude mice, the tumor inhibition was markedly enhanced accompanied by elevation of the apoptosis index after intratumoral injection of Ad-dCK and Ad-p8-siRNA on the basis of intraperitoneal gemcitabine chemotherapy. Taken together, the present findings suggest that, dCK and p8 may be the important factors in the regulation of gemcitabine sensitivity in pancreatic cancer cells. Moreover, co-regulation of the two factors achieved better effects than regulation of either one alone.
authors.affiliation: Department of General Surgery, Beijing Friendship Hospital, Capital Medical University, 95 Yongan Road, Xuanwu District, Beijing 100050, PR China.
authors.forename: Ke
authors.initials: K
authors.lastname: Tang
authors.forename: Zhongtao
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Bai
authors.forename: Xuemei
authors.initials: X
authors.lastname: Ma
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D017209:Apoptosis; D051792:Basic Helix-Loop-Helix Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D049109:Cell Proliferation; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D003842:Deoxycytidine Kinase / Q000235:genetics / Q000378:metabolism*; D019008:Drug Resistance, Neoplasm / Q000502:physiology*; D005260:Female; D005822:Genetic Vectors; D006801:Humans; D007124:Immunoenzyme Techniques; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D051792:Basic Helix-Loop-Helix Proteins; D053148:Caspase 3; D003841:Deoxycytidine; D003842:Deoxycytidine Kinase; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000093542:Gemcitabine; C491643:NUPR1 protein, human