[Effect of H. pylori on the expression of CCAAT enhancer binding protein α and Cx43 and its role in gastric carcinogenesis].
OBJECTIVE
To explore the effect of H. pylori on the expression of CCAAT enhancer binding protein α (C/EBPα) and connexin 43 (Cx43) in gastric carcinogenesis.


METHODS
Different gastric mucosal epithelial cell lines (GES-1 cells, AGS cells and SGC-7901 cells) were cultured. A total of 6 cases of chronic non-atrophic gastritis tissues, 12 cases of gastric precancerous lesions tissues and 12 cases of gastric cancer tissues were collected under endoscopy. The expression of C/EBPα and Cx43 mRNA in the above-mentioned cells and tissues was detected by real-time PCR. The GES-1 cells and East Asian CagA+ H. pylori strains were co-cultured for 24 and 48 h as an experimental group, and those cell lines without H. pylori infection were cultured for 24 and 48 h as a control group. Real-time PCR and Western bolt were used to detect the expression of mRNA and proteins of C/EBPα and Cx43 in GES-1 cells, respectively.


RESULTS
The expressions of C/EBPα and Cx43 mRNA in the AGS and SGC-7901 cells were lower than those in GES-1 cells (all P<0.05), and both of them decreased more profoundly in the SGC-7901 cells than those in the AGS cells (both P<0.05). The expressions of C/EBPα and Cx43 mRNA were lower in the gastric cancer tissues than those in the chronic non-atrophic gastritis tissues (both P<0.05) and gastric precancerous lesion tissues (both P<0.05). The C/EBPα expression was positively correlated with Cx43 expression (gastric precancerous lesion tissues: r=0.679, gastric cancer tissues: r=0.792; both P<0.05). Compared with the control group, the expressions of C/EBPα and Cx43 mRNA and protein in the experimental group were decreased at 24 and 48 h after culture (both P<0.05), which were lower at 48 h than those at 24 h (both P<0.05).


CONCLUSIONS
H. pylori infection can down-regulate the expressions of C/EBPα and Cx43 on gastric epithelial cells, which may be associated with gastric carcinogenesis.
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013; Department of Internal Medicine, Hunan Provincial Maternal and Child Health Care Hospital, Changsha 410008,China.
Li
L
Zhou
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013; Hunan Key Laboratory of Nonresolving Inflammation and Cancer, Changsha 410013, China.
Canxia
C
Xu
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013, China.
Tingzi
T
Hu
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013, China.
Xiaoming
X
Liu
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013, China.
Jing
J
Xiao
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013, China.
Ling
L
Luo
Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013, China.
Xiaoxia
X
Jiang
D022763:CCAAT-Enhancer-Binding Protein-alpha; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D018031:Connexin 43; D015536:Down-Regulation; D005753:Gastric Mucosa; D016481:Helicobacter Infections; D016480:Helicobacter pylori; D006801:Humans; D012333:RNA, Messenger; D060888:Real-Time Polymerase Chain Reaction; D013274:Stomach Neoplasms
D022763:CCAAT-Enhancer-Binding Protein-alpha; D018031:Connexin 43; C500216:GJA1 protein, human; D012333:RNA, Messenger