Lack of evidence of association of p21(WAF1/CIP1) polymorphism with lung cancer susceptibility and prognosis in Taiwan

An association between the Arg allele of the p21(WAF1/CIP1) codon 31 polymo rphism and lung cancer has been reported. However, the genotype distributio n of the p21 codon 31 polymorphism, as well as the association of this poly morphism with lung cancer risk and prognosis, remain undefined in the Taiwa nese population. Therefore, we investigated the genotype distribution of th e p21 codon 31 polymorphism in 155 lung cancer patients and 189 non-cancer controls. The genotype frequencies in the Taiwanese non-cancer controls wer e 0.51 (Ser) and 0.49 (Arg). chi(2) analysis indicated significant differen ces in Taiwanese genotype distribution of p21 from those reported for Swede s (P=0.001), Caucasians (P=0.001), Indians (P=0.001), and African-Americans (P=0.001), However, our data did not demonstrate an association of the Arg allele of the p21 polymorphism with lung cancer risk in Taiwan, Lung cance r patients with Ser/Arg and Arg/Arg genotypes were at a nonsignificant 1.15 -fold increased risk of lung cancer when compared to individuals with the S er/Ser genotype (95% CI, 0.70-1.86). In addition, although p21 is a downstr eam target of p53, we found no significant correlation of the p21 polymorph ism with the p53 polymorphism and p53 gene mutation in lung cancer patients . We further investigated the association of the p21 polymorphism with prog nosis in 154 lung cancer patients. Patients with the Ser/Ser genotype tende d to have a poorer prognosis than those with the Ser/Arg and Arg/Arg genoty pes (P=0.097, by the log rank test). Our data suggest that the p21 codon 31 polymorphism may not play a significant role in cancer susceptibility and the prognosis of lung cancer patients in Taiwan.