Association between the p73 exon 2 G4C14-to-A4T14 polymorphism and cancer risk: a meta-analysis.

The TP53 homolog p73 is structurally and functionally similar to TP53 and plays an important role in modulating cell-cycle control, apoptosis, and cell growth. G4C14-to-A4T14 is the most commonly studied polymorphism of this gene for its association with risk of cancers, but the results are confusing rather than conclusive. We performed a meta-analysis using 21 eligible studies with a total of 7581 patients and 10,413 controls to summarize the data for an association between the p73 G4C14-to-A4T14 polymorphism and cancer risk. Compared with the common GC/GC genotype, the AT carriers (AT/GC, AT/AT) had a 1.18-fold elevated risk of cancer (95% confidence interval [CI]=1.11-1.25, p<0.00001) in a dominant genetic model as estimated in a fixed effect model. The effect of the G4C14-to-A4T14 polymorphism was further evaluated through stratification analysis. In four lung cancer studies, the variant genotypes had a significantly increased risk of lung cancer (odds ratio [OR]=1.16, 95% CI=1.04-1.28, p=0.005). Similar phenomena were also found in two squamous cell carcinoma of the head and neck studies (OR=1.32, 95% CI=1.12-1.56, p=0.0010), two oral cancer studies (OR=1.57, 95% CI=1.26-1.95, p<0.0001), and three colorectal cancer studies (OR=1.23, 95% CI=1.01-1.50, p=0.04). Increased risk of cancer associated with G4C14-to-A4T14 variant genotypes was pronounced in Caucasians (OR=1.21, 95% CI=1.11-1.31, p<0.00001), the Japanese population (OR=1.24, 95% CI=1.01-1.52, p=0.04), and the Korean population (OR=1.27, 95% CI=1.07-1.52, p=0.007). Our meta-analysis suggests that the p73 G4C14-to-A4T14 polymorphism genotypes (GC/AT+AT/AT) may be associated with an increased risk of cancer in most cancer types and ethnicities.