Association of MUTYH Gln324His and APEX1 Asp148Glu with colorectal cancer and smoking in a Japanese population.
BACKGROUND
Genetic polymorphisms of DNA repair enzymes may lead to genetic instability and colorectal cancer carcinogenesis. Our objective was to measure the interactions between polymorphisms of repair genes and tobacco smoking in colorectal cancer.


METHODS
The case-control study involved sixty-eight colorectal cancer patients and 121 non-cancer controls divided into non-smokers and smokers according to pack-years of smoking. The genetic polymorphisms of DNA repair enzymes,OGG1 Ser326Cys, MUTYH Gln324His, APEX1 Asp148Glu and XRCC1 Arg399Gln, were examined using PCR-RFLP.


RESULTS
The MUTYH Gln324His showed strong significant associations with a risk of colorectal cancer (crude odds ratio [OR] 3.30, 95% confidence interval [95%CI] 1.44-7.60, p = 0.005; adjusted OR3.53, 95%CI 1.44-8.70, p = 0.006). The ORs for the APEX1 Asp148Glu were statistically significant (crude OR 2.69, 95%CI 1.45-4.99, p = 0.002; adjusted OR 2.33, 95%CI 1.21-4.48, p = 0.011). The ORs for the MUTYH Gln324His and the APEX1 Asp148Glu were statistically significant for colon cancer (adjusted OR 3.95, 95%CI 1.28-12.20, p = 0.017 for MUTYH Gln324His ; adjusted OR 3.04, 95%CI 1.38-6.71, p = 0.006 for APEX1 Asp148Glu). The joint effect of tobacco exposure and the MUTYH Gln324His showed a significant association with colorectal cancer risk in non-smokers (adjusted OR 4.08, 95%CI 1.22-13.58, p = 0.022) and the APEX1 Asp148Glu was significantly increased in smokers (adjusted OR 5.02, 95%CI 1.80-13.99, p = 0.002). However, the distributions of OGG1 Ser326Cys and XRCC1 Arg399Gln were not associated with a colorectal cancer risk.


CONCLUSIONS
Our findings suggest that the MUTYH Gln324His and the APEX1 Asp148Glu constitutes an increased risk of colorectal cancer, especially colon cancer. The MUTYH Gln324His is strongly associated with colorectal cancer susceptibility in never smoking history, whereas the APEX1 Asp148Glu genotype constitutes an increased risk of colorectal cancer when accompanied by smoking exposure.
Kasahara
Mayumi
M
Faculty of Health Sciences, Kobe University Graduate School of Medicine, Kobe, Japan. mayu-cherry10@ja3.so-net.ne.jp
Osawa
Kayo
K
Yoshida
Kana
K
Miyaishi
Aiko
A
Osawa
Yasunori
Y
Inoue
Natsuko
N
Tsutou
Akimitsu
A
Tabuchi
Yoshiki
Y
Tanaka
Kenichi
K
Yamamoto
Masahiro
M
Shimada
Etsuji
E
Takahashi
Juro
J
D000368:Aged; D044466:Asian People / Q000235:genetics; D001224:Aspartic Acid / Q000235:genetics; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000235:genetics*; D045647:DNA Glycosylases / Q000235:genetics*; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D018698:Glutamic Acid / Q000235:genetics; D005973:Glutamine / Q000235:genetics; D006639:Histidine / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012907:Smoking / Q000009:adverse effects* / Q000235:genetics
D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; D006639:Histidine; D045647:DNA Glycosylases; C061738:mutY adenine glycosylase; C085108:APEX1 protein, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase