Cancer is one the most concerning complications of longstanding
ulcerative colitis (UC). This study was undertaken to investigate the
possible association between eNOS gene intron 4 polymorphism and
the development of UC-associated colorectal cancer. It was carried
out on 120 subjects; distributed as follows: 40 patients with UC
associated colorectal cancer, 40 patients with UC who did not develop
colorectal cancer and 40 control subjects. Genotypes (aa, bb, ab) for
eNOS gene intron 4 polymorphism were identified using amplified
fragment length polymorphism PCR. Plasma nitrate and nitrite levels
were used to estimate the amounts of endogenous nitric oxide
formation using nitric oxide colorimetric assay kit. Our preliminary
data revealed that, compared to the bb genotype, the aa and ab eNOS
genotypes were significantly associated with increased risk of
developing UC associated colorectal cancer. Meanwhile, in UC
associated - colorectal cancer and UC patients groups, plasma NO
levels were higher in patients with 4a4a/4a4b genotypes compared to
those with bb genotype. It can be concluded from our preliminary study that a allele variant of eNOS intron 4 polymorphism may be
associated with increased risk of development of UC associated
colorectal cancer, however, large scaled studies are needed to verify
these preliminary results.