Lung cancer risk associated with genetic polymorphism in myeloperoxidase (-463 G/A) in a Chinese population / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To examine the relationship between susceptibility to lung cancer among Chinese and genetic polymorphism at nucleotide -463 (G/A) in myeloperoxidase (MPO), an enzyme found in lysosomes of phagocytes and involved in the formation of hydroxyl radicals and activation of various smoking-related carcinogens.</p><p><b>METHODS</b>The association of this polymorphism with lung cancer in a hospital-based case-control study of 314 patients and 320 age- and sex-matched controls was tested. The MPO genotypes were determined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP).</p><p><b>RESULTS</b>The allele frequency for MPO-463A was found to be 11.0% for controls, compared with 15.0% for patients. Multivariate analysis showed an increased risk for overall lung cancer in subjects having GG genotype (OR, 1.7; 95% CI, 1.2 - 2.5), however, the elevated risk was limited to squamous cell carcinoma (OR, 2.4; 95% CI, 1.4 - 3.9; n = 177) but not to adenocarcinoma (OR, 1.3; 95% CI, 0.8 - 2.1; n = 137). In addition, the risky effect of the GG genotype on squamous cell carcinoma of the lung was evident only in the smokers and those who smoked >/= 26 pack-years (OR, 20.5; 95% CI, 5.6 - 75.3) as compared with GA and AA genotypes (OR, 6.2; 95% CI, 1.7 - 22.5) but not in the nonsmokers or those who smoked < 26 pack-years.</p><p><b>CONCLUSION</b>Our data support the hypothesis that -463A polymorphism in the MPO gene may reduce the susceptibility to lung cancer in the Chinese.</p>

p53 gene codon 72 polymorphism and susceptibility to esophageal squamous cell carcinoma in a Chinese population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between p53 codon 72 polymorphism and susceptibility to esophageal squamous cell carcinoma in China.</p><p><b>METHODS</b>The p53 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism among 204 healthy controls and 91 patients with esophageal squamous cell carcinoma (ESCC).</p><p><b>RESULTS</b>There was no significant difference between patients and controls with respect to allele frequency for the p53 Pro allele (0.480 versus 0.588, P=0.11); however, the Pro/Pro genotype of p53 among cases (39.6%) was significantly (P<0.05) more frequent than that among controls (21.1%). Subjects homozygous for the p53 Pro allele had a more than 2-fold increased risk of developing ESCC (OR=2.18; 95%CI=1.10-4.35, adjusted for age, sex, and smoking), whereas the Arg/Pro genotype was not associated with elevated risk of the cancer (adjusted OR=0.84; 95%CI=0.42-1.68). No interaction between smoking and Pro/Pro genotype was observed for risk of ESCC.</p><p><b>CONCLUSION</b>The p53 codon 72 polymorphism may play a role in susceptibility to esophageal carcinogenesis.</p>

Study on the association between smoking behavior and dopamine receptor D2 gene polymorphisms among lung cancer cases / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the possible association between dopamine D2 receptor (DRD2) TaqI A and TaqI B genotypes as well as smoking behavior and the risk of lung cancer among Chinese Han people.</p><p><b>METHODS</b>PCR was used to perform genotyping on peripheral WBC DNA from 326 lung cancer patients and 326 age, sex and ethnicity-matched healthy controls. Subjects were interviewed to obtain relevant information and lifetime history of tobacco use.</p><p><b>RESULTS</b>There were no statistically significant differences in the distribution of DRD2 genotypes between lung cancer cases and controls. The DRD2 genotypes and smoking status showed no correlation among cases and among controls as well. However, among controls, the frequency of the DRD2 * A2/A2 genotype in smokers who smoked > or = 25 cigarettes/day appeared to be higher than that in those who smoked < 25 cigarettes/day (42.5% versus 26.1%, P = 0.047). A similar trend was also found for the DRD2 * B2/B2 genotype, which was linked to the DRD2 * A2/A2 genotype, although the difference was not significant (40.0% versus 26.1%, P = 0.091). In contrast to controls, no association was found between the DRD2 genotypes and smoking among lung cancer cases.</p><p><b>CONCLUSION</b>Our results suggested that DRD2 * A2/A2 genotype might be associated with a greater smoking intensity in Chinese. Further studies are needed to confirm this preliminary finding.</p>