GSTT1-null genotype is a protective factor against bladder cancer.
OBJECTIVE
To investigate the effects of homozygous deletions of GSTM1 and GSTT1 and smoking on bladder cancer, we conducted a case-control and ecological study.


METHODS
The case group consisted of 216 patients with bladder cancer and the control group of 449 healthy Koreans. Every subject was personally interviewed to obtain a detailed smoking history, and a multiplex polymerase chain reaction method was used to detect the presence or absence of the GSTM1 and GSTT1 genes. In the ecological study, age-standardized bladder cancer incidence and frequencies of GSTM1 and GSTT1-null types, estimated prevalence of cigarette smoking, and estimated per capita consumption of cigarettes per adult according to nationality and ethnicity were included.


RESULTS
In the Korean case-control data, smoking history and the GSTT1-null genotype were significantly associated with bladder cancer, and the GSTM1-null genotype was not. In the univariate and multivariate analyses with the ecological data of various countries and ethnic groups, cigarette smoking positively, but the frequency of the GSTT1-null type negatively, correlated with the age-standardized bladder cancer incidence.


CONCLUSIONS
These results suggest that the GSTT1-negative genotype might not be a risk factor but a protective factor of bladder cancer.
Kim
Wun-Jae
WJ
Department of Urology, Chungbuk National University College of Medicine, Cheongju, South Korea.
Kim
Heon
H
Kim
Cheol-Hwan
CH
Lee
Moo-Song
MS
Oh
Bong Ryoul
BR
Lee
Hyun Moo
HM
Katoh
Takahiko
T
D000704:Analysis of Variance; D002295:Carcinoma, Transitional Cell / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D016001:Confidence Intervals; D005260:Female; D017353:Gene Deletion; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012306:Risk; D012907:Smoking / Q000009:adverse effects*; D001749:Urinary Bladder Neoplasms / Q000208:ethnology / Q000235:genetics*
D005982:Glutathione Transferase; C413545:glutathione S-transferase T1