Association of Helicobacter pylori with colorectal cancer development.
Background: Helicobacter pylori (H. pylori) may be associated with colorectal cancer. However, the underlying mechanisms are still unclear. Objectives: Explore the serostatus of H. pylori cytotoxicity-associated gene A product (CagA) in patients with colorectal carcinoma, and assess the associatio...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English English |
| Published: |
IOS Press
2010
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| Online Access: | http://psasir.upm.edu.my/id/eprint/13314/ http://psasir.upm.edu.my/id/eprint/13314/1/Association%20of%20Helicobacter%20pylori%20with%20colorectal%20cancer%20development.pdf |
| Summary: | Background: Helicobacter pylori (H. pylori) may be associated with colorectal cancer. However, the underlying
mechanisms are still unclear.
Objectives: Explore the serostatus of H. pylori cytotoxicity-associated gene A product (CagA) in patients with colorectal carcinoma, and assess the association of H. pylori with colorectal cancer via c-Myc and MUC-2
proteins at tumor tissues.
Methods: H. pylori CagA IgG antibodies were screened using enzyme-linked immunosorbent assay (ELISA) in
30 patients with colorectal carcinoma and 30 cancer-free control subjects. Paraffin-embedded blocks were examined
for the expression of c-Myc and MUC-2 protein by immunohistochemistry.
Results: H. pylori CagA seropositivity increased significantly among colorectal cancer patients (p <0.05).
The expression of c-Myc and MUC-2 in colorectal carcinoma patients was over-expressed (80%), and downexpressed
(63%) in resection margins (p <0.05). c-Myc over-expression and MUC-2 down-expression were
associated with CagA-positive rather than CagA-negative H. pylori patients. In 16 CagA seropositive vs. 14 CagA
seronegative patients, the expression rate was 97.3% vs. 64.2% and 33.3% vs. 78.5% for cMyc and MUC-2,
respectively. CagA IgG level was significantly higher in positive than in negative c-Myc patients (p= 0.036), and
in negative than in positive MUC-2 patients (p= 0.044). c-Myc and MUC-2 were positively and inversely correlated
with CagA IgG level (p <0.05).
Conclusions: CagA-seropositive H. pylori is most probably associated with colorectal cancer development.
Part of the underlying mechanism for such association might be via alterations in expression of MUC-2, which
depletes the mucous protective layer in the colo-rectum, and c-Myc, which stimulates the growth of cancerous
cells. |
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