Upregulation of human DNA binding protein A (dbpA) in gastric cancer cells.
OBJECTIVE
To determine the effect of human DNA binding protein (dbpA) on the biology of gastric cancer cells.


METHODS
DbpA expression was analyzed by Western blot analysis and immunofluorescence staining in gastric cancer tissues and cell lines. A dbpA-specific small interference (si) RNA was designed and synthesized. Suppressive effect of siRNA on dbpA expression was assessed by real-time RT-PCR. Transwell migration and colony formation assays were used to assess the inhibitory effects of dbpA siRNA on cell invasion and tumorigenesis in vitro. Drug-sensitivity was evaluated using a conventional 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay.


RESULTS
The expression of dbpA was upregulated in gastric cancer tissues and cell lines as compared to adjacent normal tissues or gastric epithelial cells. siRNA treatment successfully silenced dbpA expression. Silencing of dbpA increased expression of E-cadherin, decreased expression of adenomatous polyposis coli (APC), beta-catenin and cyclin D1, but had no effect on expression of NF-kappaB. Silencing of dbpA also suppressed cell invasion and colony formation of SGC7901 cells, and enhanced their chemosensitivity to 5-fluorouracil.


CONCLUSIONS
DbpA plays an important role in the pathogenesis and development of gastric cancer, and the process involves E-cadherin, APC, beta-catenin and cyclin D1. Silencing of dbpA might be a novel therapeutic strategy for increasing chemosensitivity to 5-fluorouracil in gastric cancer.
Wang
Guo-rong
GR
Department of General Surgery, First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an 710061, China.
Zheng
Yan
Y
Che
Xiang-ming
XM
Wang
Xin-yang
XY
Zhao
Jia-hui
JH
Wu
Kai-jie
KJ
Zeng
Jin
J
Pan
Chen-en
CE
He
Da-lin
DL
D025601:Adenomatous Polyposis Coli Protein / Q000235:genetics / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology; D022762:CCAAT-Enhancer-Binding Proteins / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D004396:Coloring Agents / Q000378:metabolism; D016895:Culture Media, Serum-Free; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D019085:Fluorescent Antibody Technique, Direct; D005472:Fluorouracil / Q000494:pharmacology; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology*; D013778:Tetrazolium Salts / Q000378:metabolism; D013844:Thiazoles / Q000378:metabolism; D014162:Transfection; D015854:Up-Regulation / Q000187:drug effects; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism
D025601:Adenomatous Polyposis Coli Protein; D000970:Antineoplastic Agents; D022762:CCAAT-Enhancer-Binding Proteins; D015820:Cadherins; D004396:Coloring Agents; D016895:Culture Media, Serum-Free; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D013778:Tetrazolium Salts; D013844:Thiazoles; C094867:YBX3 protein, human; D051176:beta Catenin; D019938:Cyclin D1; C022616:thiazolyl blue; D005472:Fluorouracil