title: Helicobacter pylori and colorectal neoplasia: Is there a causal link?
abstract: Ever since Helicobacter pylori (H. pylori) was recognized as an infectious cause of gastric cancer, there has been increasing interest in examining its potential role in colorectal carcinogenesis. Data from case-control and cross-sectional studies, mostly relying on hospital-based samples, and several meta-analyses have shown a positive statistical relationship between H. pylori infection and colorectal neoplasia. However, the possibility exists that the results have been influenced by bias, including the improper selection of patients and disparities with respect to potential confounders. While the evidence falls short of a definitive causal link, it appears that infection with H. pylori/H. pylori-related gastritis is associated with an increased, although modest, risk of colorectal adenoma and cancer. The pathogenic mechanisms responsible for this association remain uncertain. H. pylori has been detected in colorectal malignant tissues; however, the possibility that H. pylori is a direct activator of colonic carcinogenesis remains purely hypothetical. On the other hand, experimental data have indicated a series of potential oncogenic interactions between these bacteria and colorectal mucosa, including induction and perpetuation of inflammatory responses, alteration of gut microflora and release of toxins and/or hormonal mediators, such as gastrin, which may contribute to tumor formation.
authors.affiliation: Vasilios Papastergiou, Stylianos Karatapanis, Department of Internal Medicine, General Hospital of Rhodes, 85100 Rhodes, Greece.
authors.forename: Vasilios
authors.initials: V
authors.lastname: Papastergiou
authors.affiliation: Vasilios Papastergiou, Stylianos Karatapanis, Department of Internal Medicine, General Hospital of Rhodes, 85100 Rhodes, Greece.
authors.forename: Stylianos
authors.initials: S
authors.lastname: Karatapanis
authors.affiliation: Vasilios Papastergiou, Stylianos Karatapanis, Department of Internal Medicine, General Hospital of Rhodes, 85100 Rhodes, Greece.
authors.forename: Sotirios D
authors.initials: SD
authors.lastname: Georgopoulos
mesh_terms: D002471:Cell Transformation, Neoplastic / Q000235:genetics; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000382:microbiology*; D005756:Gastritis / Q000175:diagnosis / Q000382:microbiology*; D016481:Helicobacter Infections / Q000150:complications / Q000175:diagnosis / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics / Q000472:pathogenicity*; D054884:Host-Pathogen Interactions; D006801:Humans; D009857:Oncogenes; D011230:Precancerous Conditions / Q000175:diagnosis / Q000235:genetics / Q000382:microbiology*; D012307:Risk Factors
keywords: Adenoma; Colorectal cancer; Gastrin; Helicobacter pylori; Polyp
references.citation: Cancer Res. 1997 Nov 1;57(21):4787-94
references.pmid: 9354440
references.citation: World J Gastroenterol. 2010 Aug 14;16(30):3841-6
references.pmid: 20698048
references.citation: Gastroenterology. 1998 Aug;115(2):275-80
references.pmid: 9679032
references.citation: Br J Surg. 1985 Aug;72(8):618-9
references.pmid: 4027533
references.citation: Oncogene. 2004 Aug 23;23(38):6445-70
references.pmid: 15322516
references.citation: Am J Gastroenterol. 2001 Jan;96(1):84-8
references.pmid: 11197293
references.citation: J Natl Cancer Inst. 1995 Dec 6;87(23):1777-80
references.pmid: 7473834
references.citation: Dig Dis Sci. 1996 Mar;41(3):604-13
references.pmid: 8617144
references.citation: J Natl Cancer Inst. 1991 Dec 4;83(23):1734-9
references.pmid: 1770552
references.citation: BMC Gastroenterol. 2008;8:35
references.pmid: 18702825
references.citation: Dig Dis Sci. 2012 Aug;57(8):2184-94
references.pmid: 22669208
references.citation: Cancer Res. 2008 Dec 1;68(23):9909-17
references.pmid: 19047172
references.citation: J Clin Med Res. 2012 Jun;4(3):172-6
references.pmid: 22719803
references.citation: Int J Cancer. 2006 Oct 15;119(8):1999-2000
references.pmid: 16708392
references.citation: J Clin Gastroenterol. 1997 Dec;25(4):605-7
references.pmid: 9451672
references.citation: Aliment Pharmacol Ther. 2007 Oct 1;26(7):1051-61
references.pmid: 17877512
references.citation: Pol J Pathol. 2014 Dec;65(4):257-66
references.pmid: 25693079
references.citation: J Gastrointest Oncol. 2012 Dec;3(4):377-9
references.pmid: 23205317
references.citation: Isr Med Assoc J. 2000 Jan;2(1):6-9
references.pmid: 10892362
references.citation: Helicobacter. 2007 Aug;12(4):328-32
references.pmid: 17669106
references.citation: Colorectal Dis. 2013 Jul;15(7):e352-64
references.pmid: 23672575
references.citation: Clin Colon Rectal Surg. 2009 Nov;22(4):191-7
references.pmid: 21037809
references.citation: Am J Gastroenterol. 2001 Dec;96(12):3406-10
references.pmid: 11774957
references.citation: J Natl Cancer Inst. 1995 May 17;87(10):762-3
references.pmid: 7563155
references.citation: Aliment Pharmacol Ther. 1997 Apr;11 Suppl 1:71-88
references.pmid: 9146793
references.citation: Int J Colorectal Dis. 2003 Mar;18(2):148-52
references.pmid: 12548418
references.citation: Dis Colon Rectum. 1997 Apr;40(4):483-93
references.pmid: 9106701
references.citation: Gastroenterology. 1997 Sep;113(3):1015-25
references.pmid: 9287997
references.citation: J Med Microbiol. 2005 Nov;54(Pt 11):1031-5
references.pmid: 16192433
references.citation: Ann Surg. 1990 Dec;212(6):714-9
references.pmid: 2256763
references.citation: Gastroenterology. 1994 May;106(5):1263-70
references.pmid: 8174887
references.citation: Gut. 1997 Sep;41(3):330-2
references.pmid: 9378387
references.citation: Gastroenterology. 2002 May;122(5):1376-87
references.pmid: 11984524
references.citation: Gastroenterology. 2003 Feb;124(2):392-400
references.pmid: 12557145
references.citation: Helicobacter. 2004;9 Suppl 1:67-72
references.pmid: 15347308
references.citation: World J Gastroenterol. 2015 Jan 7;21(1):112-23
references.pmid: 25574084
references.citation: Int J Cancer. 2011 Dec 1;129(11):2704-11
references.pmid: 21225622
references.citation: Eur J Gastroenterol Hepatol. 2013 Nov;25(11):1286-94
references.pmid: 23820245
references.citation: Br J Surg. 1988 Apr;75(4):342-5
references.pmid: 3359147
references.citation: Methods Mol Biol. 2009;472:361-72
references.pmid: 19107442
references.citation: Regul Pept. 2006 Mar 15;134(1):9-16
references.pmid: 16297463
references.citation: Int J Oncol. 2013 Oct;43(4):973-84
references.pmid: 23900573
references.citation: Semin Cancer Biol. 2013 Dec;23(6 Pt B):492-501
references.pmid: 23876852
references.citation: Biochem Biophys Res Commun. 2009 Apr 17;381(4):666-70
references.pmid: 19248769
references.citation: Int J Colorectal Dis. 2001 Aug;16(4):202-10
references.pmid: 11515678
references.citation: Cancer Epidemiol Biomarkers Prev. 2010 Aug;19(8):1893-907
references.pmid: 20647400
references.citation: BMJ. 2000 Sep 30;321(7264):805-8
references.pmid: 11009523
references.citation: Cancer Epidemiol Biomarkers Prev. 2002 Oct;11(10 Pt 1):1095-9
references.pmid: 12376513
references.citation: Am J Gastroenterol. 2013 Feb;108(2):208-15
references.pmid: 23208272
references.citation: Cancer Res. 1993 Jun 15;53(12):2919-26
references.pmid: 8504433
references.citation: Int J Hematol. 2013 Jun;97(6):735-42
references.pmid: 23616223
references.citation: Clin Microbiol Infect. 2006 Aug;12(8):782-6
references.pmid: 16842574
references.citation: Int J Cancer. 2005 Dec 20;117(6):1058-9
references.pmid: 15986436
references.citation: Cancer Causes Control. 2010 Jan;21(1):163-70
references.pmid: 19838812
references.citation: Mol Clin Oncol. 2013 Jan;1(1):75-82
references.pmid: 24649126
references.citation: Am J Epidemiol. 2012 Mar 1;175(5):441-50
references.pmid: 22294430
references.citation: Gastroenterology. 1993 Jul;105(1):22-30
references.pmid: 8514038
references.citation: CA Cancer J Clin. 2012 Jan-Feb;62(1):10-29
references.pmid: 22237781
references.citation: Scand J Gastroenterol. 2014 Jan;49(1):35-42
references.pmid: 24164483
references.citation: Cancer Res. 1992 Apr 15;52(8):2261-7
references.pmid: 1559230
references.citation: Chemotherapy. 2005;51 Suppl 1:1-22
references.pmid: 15855746
references.citation: Digestion. 1999;60(3):210-5
references.pmid: 10343134
references.citation: JAMA. 1999 Dec 15;282(23):2240-5
references.pmid: 10605976
references.citation: Int J Cancer. 2014 Sep 1;135(5):1127-31
references.pmid: 24496701
references.citation: Am J Gastroenterol. 2013 Feb;108(2):216-7
references.pmid: 23381070
references.citation: Prilozi. 2007 Dec;28(2):25-38
references.pmid: 18356777
references.citation: Ann R Coll Surg Engl. 1992 Mar;74(2):138-40; discussion 141
references.pmid: 1567134
references.citation: J Infect Dis. 2000 Apr;181(4):1359-63
references.pmid: 10762567
references.citation: Helicobacter. 2006 Apr;11(2):75-80
references.pmid: 16579836
references.citation: Colorectal Dis. 2010 Jan;12(1):48-53
references.pmid: 20050183
references.citation: Digestion. 2006;74(1):42-6
references.pmid: 17068397
references.citation: J Clin Invest. 1996 Oct 15;98(8):1918-29
references.pmid: 8878444
references.citation: Cytokine. 2000 Jan;12(1):78-85
references.pmid: 10623446
references.citation: Intern Emerg Med. 2014 Apr;9(3):303-9
references.pmid: 23054412
references.citation: Peptides. 1997;18(4):559-65
references.pmid: 9210176
references.citation: J Cancer Res Ther. 2014 Dec;10 Suppl:263-6
references.pmid: 25693932
references.citation: Curr Opin Gastroenterol. 2000 Jan;16(1):68-77
references.pmid: 17024020
references.citation: BMC Cancer. 2014;14:296
references.pmid: 24774100
references.citation: IARC Monogr Eval Carcinog Risks Hum. 1994;61:177-240
references.pmid: 7715070
references.citation: Dig Liver Dis. 2012 Sep;44(9):793-7
references.pmid: 22595617
references.citation: Br J Surg. 1987 Jul;74(7):573-5
references.pmid: 3620860
references.citation: J Gastrointest Oncol. 2014 Dec;5(6):463-8
references.pmid: 25436126
references.citation: PLoS One. 2011;6(1):e16393
references.pmid: 21297998
references.citation: Lab Invest. 2004 Jul;84(7):884-93
references.pmid: 15122305
references.citation: World J Surg Oncol. 2007;5:51
references.pmid: 17498313
references.citation: J Gastroenterol. 2005 Sep;40(9):887-93
references.pmid: 16211345
references.citation: Int J Colorectal Dis. 2008 Sep;23(9):875-82
references.pmid: 18506454
references.citation: Am J Surg. 1985 Jan;149(1):35-9
references.pmid: 3966639
references.citation: J Physiol Pharmacol. 1999 Dec;50(5):857-73
references.pmid: 10695565
references.citation: Asian Pac J Cancer Prev. 2013;14(12):7613-9
references.pmid: 24460342
references.citation: Gastroenterology. 1991 Sep;101(3):711-5
references.pmid: 1860635
references.citation: Regul Pept. 2000 Sep 25;93(1-3):13-9
references.pmid: 11033048
references.citation: Am J Gastroenterol. 1992 Oct;87(10):1394-7
references.pmid: 1415093
references.citation: J Clin Invest. 1999 Apr;103(8):1119-26
references.pmid: 10207163