Effects of the Helicobacter pylori Virulence Factor CagA and Ammonium Ion on Mucins in AGS Cells

다국어 초록 (Multilingual Abstract)

Purpose: To investigate the effects of Helicobacter pylori (H. pylori)-CagA and the urease metabolite NH4 + on mucin expression inAGS cells.
Materials and Methods: AGS cells were transfected with CagA and/or treated with different concentrations of NH4CL. Mucingene and protein expression was assessed by qPCR and immunofluorescence assays, respectively.
Results: CagA significantly upregulated MUC5AC, MUC2, and MUC5B expression in AGS cells, but did not affect E-cadherin andMUC6 expression. MUC5AC, MUC6, and MUC2 expression in AGS cells increased with increasing NH4 + concentrations untilreaching a peak level at 15 mM. MUC5B mRNA expression in AGS cells (NH4 + concentration of 15 mM) was significantly higherthan that at 0, 5, and 10 mM NH4 + . No changes in E-cadherin expression in AGS cells treated with NH4 + were noted, except at 20mM. The expression of MUC5AC, MUC2, and MUC6 mRNA in CagA-transfected AGS cells at an NH4 + concentration of 15 mM wassignificantly higher than that at 0 mM, and decreased at higher concentrations. The expression of MUC5B mRNA increased withincreases in NH4 + concentration, and was significantly higher compared to that in untreated cells. No significant change in the expressionof E-cadherin mRNA in CagA-transfected AGS cells was observed. Immunofluorescence assays confirmed the observedchanges.
Conclusion: H. pylori may affect the expression of MUC5AC, MUC2, MUC5B, and MUC6 in AGS cells via CagA and/or NH4 + , butnot E-cadherin.

참고문헌 (Reference)

1 Shi D, "The changes in MUC5AC expression in gastric cancer before and after Helicobacter pylori eradication" 38 : 235-240, 2014

2 Van de Bovenkamp JH, "The MUC5AC glycoprotein is the primary receptor for Helicobacter pylori in the human stomach" 8 : 521-532, 2003

3 Hayashi T, "Tertiary structure-function analysis reveals the pathogenic signaling potentiation mechanism of Helicobacter pylori oncogenic effector CagA" 12 : 20-33, 2012

4 Meng W, "Role of Helicobacter pylori in gastric cancer: advances and controversies" 20 : 285-293, 2015

5 Matsuda K, "Quantitative analysis of the effect of Helicobacter pylori on the expressions of SOX2, CDX2, MUC2, MUC5AC, MUC6, TFF1, TFF2, and TFF3 mRNAs in human gastric carcinoma cells" 43 : 25-33, 2008

6 Chan AO, "Promoter methylation of E-cadherin gene in gastric mucosa associated with Helicobacter pylori infection and in gastric cancer" 52 : 502-506, 2003

7 Wen R, "Polymorphisms in mucin genes in the development of gastric cancer" 7 : 328-337, 2015

8 Hollingsworth MA, "Mucins in cancer: protection and control of the cell surface" 4 : 45-60, 2004

9 Ho SB, "Mucin gene expression in normal, preneoplastic, and neoplastic human gastric epithelium" 55 : 2681-2690, 1995

10 Zheng H, "MUC6 down-regulation correlates with gastric carcinoma progression and a poor prognosis: an immunohistochemical study with tissue microarrays" 132 : 817-823, 2006

11 Pinto-de-Sousa J, "MUC5B expression in gastric carcinoma: relationship with clinico-pathological parameters and with expression of mucins MUC1, MUC2, MUC5AC and MUC6" 444 : 224-230, 2004

12 Reis CA, "Intestinal metaplasia of human stomach displays distinct patterns of mucin (MUC1, MUC2, MUC5AC, and MUC6) expression" 59 : 1003-1007, 1999

13 Byrd JC, "Inhibition of gastric mucin synthesis by Helicobacter pylori" 118 : 1072-1079, 2000

14 Mejoas-Luque R, "Inflammation modulates the expression of the intestinal mucins MUC2 and MUC4 in gastric tumors" 29 : 1753-1762, 2010

15 Van De Bovenkamp JH, "Infection with Helicobacter pylori affects all major secretory cell populations in the human antrum" 50 : 1078-1086, 2005

16 Reis CA, "Immunohistochemical study of the expression of MUC6 mucin and co-expression of other secreted mucins (MUC5AC and MUC2) in human gastric carcinomas" 48 : 377-388, 2000

17 Perrais M, "Helicobacter pylori urease and flagellin alter mucin gene expression in human gastric cancer cells" 17 : 235-246, 2014

18 Yu H, "Helicobacter pylori promotes epithelial-mesenchymal transition in gastric cancer by downregulating programmed cell death protein 4 (PDCD4)" 9 : e105306-, 2014

19 Figura N, "Helicobacter pylori infection and gastric carcinoma: not all the strains and patients are alike" 8 : 40-54, 2016

20 Niv Y, "Helicobacter pylori and gastric mucin expression: a systematic review and meta-analysis" 21 : 9430-9436, 2015

21 Wu J, "Helicobacter pylori CagA: a critical destroyer of the gastric epithelial barrier" 58 : 1830-1837, 2013

22 Zhang BG, "Helicobacter pylori CagA induces tumor suppressor gene hypermethylation by upregulating DNMT1 via $AKT-NF{\kappa}B$ pathway in gastric cancer development" 7 : 9788-9800, 2016

23 Li N, "H. pylori related proinflammatory cytokines contribute to the induction of miR-146a in human gastric epithelial cells" 39 : 4655-4661, 2012

24 McLean MH, "Genetics of gastric cancer" 11 : 664-674, 2014

25 Schmitz JM, "Gastric mucus alterations associated with murine Helicobacter infection" 57 : 457-467, 2009

26 Gomceli I, "Gastric carcinogenesis" 18 : 5164-5170, 2012

27 Babu SD, "Expression profile of mucins (MUC2, MUC5AC and MUC6) in Helicobacter pylori infected pre-neoplastic and neoplastic human gastric epithelium" 5 : 10-, 2006

28 Yu XW, "Expression of the E-cadherin/${\beta}$-catenin/tcf-4 pathway in gastric diseases with relation to Helicobacter pylori infection: clinical and pathological implications" 15 : 215-220, 2014

29 Shi D, "Effects of Helicobacter pylori infection on MUC5AC protein expression in gastric cancer" 9 : 115-120, 2013

30 Kang HM, "Effects of Helicobacter pylori Infection on gastric mucin expression" 42 : 29-35, 2008

31 Tohidpour A, "CagA-mediated pathogenesis of Helicobacter pylori" 93 : 44-55, 2016

32 정우철, "An Inverse Relationship between the Expression of the Gastric Tumor Suppressor RUNX3 and Infection with Helicobacter pylori in Gastric Epithelial Dysplasia" 거트앤리버 발행위원회 7 (7): 688-695, 2013

33 Byrd JC, "Aberrant expression of gland-type gastric mucin in the surface epithelium of Helicobacter pylori-infected patients" 113 : 455-464, 1997

34 Wagih HM, "A study of RUNX3, Ecadherin and ${\beta}$-catenin in CagA-positive Helicobacter pylori associated chronic gastritis in Saudi patients" 19 : 1416-1429, 2015

35 Kocer B, "A confirmatory report for the close interaction of Helicobacter pylori with gastric epithelial MUC5AC expression" 38 : 496-502, 2004