Systematic review and meta-analysis of the association between P53 codon 72 polymorphism and colorectal cancer.

BACKGROUND: A number of studies has evaluated the association between P53 codon 72 polymorphism and colorectal cancer. However, results were inconsistent. To clarify the role of this polymorphism in colorectal cancer, we conducted a meta-analysis on this topic. METHODS: Two authors independently searched the PubMed and EMBASE database from 1966 to January 2010 for studies regarding the association of P53 codon 72 polymorphism with colorectal cancer. Summary odds ratios with their corresponding 95% confidence intervals were calculated by using random-effects model. RESULTS: The combined results showed that P53 codon 72 variant genotypes were not associated with colorectal cancer risk when compared to Arg/Arg genotype (Pro/Pro: OR = 1.02, 95% CI = 0.80-1.29; Arg/Pro: OR = 1.00, 95% CI = 0.86-1.16; Pro allele: OR = 1.00, 95% CI = 0.86-1.17). When stratifying for study population, design and cancer location, no statistically significant results were observed either. CONCLUSION: Our data indicate that the P53 codon 72 polymorphism may be not associated with colorectal cancer risk.

Tissue inhibitor of metalloproteinase-2 G-418C polymorphism is associated with an increased risk of gastric cancer in a Chinese population.

AIMS: To examine the effect of the TIMP-2 G-418C polymorphism on gastric cancer risk. METHODS: We conducted a hospital-based, case-control study using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 412 individuals (206 gastric cancer patients and 206 age, sex matched cancer-free controls). RESULTS: The genotype and allele frequencies were significantly different (P = 0.007 and 0.005, respectively) between cases and controls. Further analysis showed that the variant TIMP-2 genotypes (CC+GC) had a 51% increased risk of gastric cancer compared with GG [adjusted odds ratio (OR) 1.51, 95% confidence interval (CI) 1.00-2.26, P = 0.049]. The elevated gastric cancer risk was especially evident in younger individuals (age < 58 years old) (adjusted OR 2.21, 95% CI 1.18-4.16) and smokers (adjusted OR 2.61, 95% CI 1.01-6.72). However, no significant association was observed between the variant genotypes and clinicopathological features of gastric cancer. CONCLUSIONS: These findings suggest that the TIMP-2 G-418C polymorphism is a genetic predisposing factor for gastric cancer.