Pten Gene Mutations Occur In Sporadic Colorectal Cancer Development

Objective To detect the mutation frequency of exon5,exon7and exon8 of PTENgene, investigate the relationship between the mutation of PTEN gene and microsatellite alterations(MA) and explore the pathogenesis of human sporadic colorectal cancer.Methods Mutation was detected at exon5,exon7 and exon8 of PTEN gene andMA was detected at microsatellite loci Bat25,Bat40 and D18S21 in tumor and adjacent colorectum tissues excised from 34 cases with sporadic colorectal cancer by polymerase chain reaction(PCR), and PCR combined with single strand conformation polymorphism(PCR-SSCP), polyacrylamide gel-electrophoresis and silver staining.Results (1)2 samples with PTEN mutation were found in 34 colorectal tumortissues. The mutation rate of the exon5,exon7 and exon8 of PTEN gene was 5.88%(2/34). No mutation was found in 34 adjacent tissues. The difference was not significant(P>0.05); (2)The mutation rate of PTEN gene in poorly differentiated carcinoma, mucoid carcinoma and in well-differentiated carcinoma samples was 12.5%(2/16) and 0,respectively.The difference was not statistically significant (P>0.05); (3)7 cases (20.59%) of 34 tumor tissues were demonstrated MA at two or more loci, as positive team. Among them one was demonstrated MA at three loci, the other six at two. No MA was found in 34 adjacent tissues, statistically significant(P<0.01); (4)The mutation frequency of PTEN gene in MA positive team was 28.57%(2/7), the difference was significant(P<0.05).Conclusions (1)Mutation of PTEN gene may play a role in pathogenesis ofhuman sporadic colorectal cancer; (2)Mutation of PTEN gene may attribuated to the development of human sporadic colorectal cancer; (3) Mutation of PTEN gene is significantly associated with MA in human colorectal cancer.Postgraduate Zhang jing (Genetics) Directed by Wang peilin Wang xiuhai...