Analysis of TP53 Codon 72 Polymorphism in Mucinous and Non-Mucinous ColorectalAdenocarcinoma in Isfahan, Iran

The tumor suppressor gene tp53 (alias p53)located on chromosome 17 is involved in various cancers.case-control studies have shown that p53 codon 72 polymorphismmodulates the prognosis and susceptibility to variousmalignancies. we undertook the present study to explore apossible association between mucinous and non-mucinousadenocarcinomas with different genotypes or alleles at codon72 of tp53.methods: the genotype distribution and allelic frequenciesfor p53 polymorphism was assessed in 46 and 134 specimensfrom patients with colorectal mucinous and non-mucinousadenocarcinomas, respectively, by using allele-specific pcr.results: the pcr products were 177bp for proline allele and141bp for arginine allele. in the mucinous samples, the genotypedistribution for p53 polymorphism showed 63%, 23.9%,and 13.1% for the arg/arg, arg/pro, and pro/pro genotypes,respectively. in the non-mucinous specimens 32.1% of thecases were arg/arg, 48.5% arg/pro, and 19.4% pro/pro. a significantdifference between the two types of adenocarcinomasfor the arg 72 arg genotype compared with (grouped) arg 72arg and pro 72 pro genotypes was noted [or=3.61 (1.76-7.27),p<0.001]. the arginine allele was found more often in patientswith mucinous adenocarcinoma [or=1.85 (1.07-3.19), p<0.03].a higher portion of dukes stage c was noted in the mucinousspecimens (p<0.02) and also mucinous specimens were seenmore often at advanced tnm stages (p=0.01).conclusion: the arg/arg genotype at p53 codon 72 is moreprevalent in mucinous colorectal carcinoma and the arginineallele may contribute to mucinous carcinogenesis. the prolineallele was associated with higher duke's staging in nonmucinousadenocarcinoma.