ABSTRACT
Background: Insulin-like growth factor 1 has an important role in cell proliferation and growth. Polymorphism in IGF-1 gene changes the level of this hormone and increases the risk of colorectal cancer. The aim of this study is to assess the incidence of IGF-1 polymorphism rs5742612 in Iranian population and to investigate the influence of this polymorphism in increasing the risk of colorectal cancer
Methods and Materials: Genotyping of IGF-1 gene was performed in a series of 110 colorectal cancer patients and 110 controls by using polymerase chain reaction and restriction fragment length polymorphism genotyping [PCR-RFLP] assays. We calculated odds ratio and confidence interval [CI] of IGF-1 genotypes to determine if these polymorphisms are associated with colorectal cancer
Results: No significant association was found between polymorphism of IGF-1 gene [rs5742612] and increased risk of colorectal cancer [p=0.92]. The odds ratio for the heterozygous genotype CT versus the normal genotype CC was 1.3 [95% CI:0.3-6.27] and the odds ratio for the mutant genotype TT versus the normal genotype CC was 0.0. The frequency of the mutant allele was 2.5%
Conclusion: These findings suggest that IGF-1 rs5742612 polymorphism is not associated with increased risk of colorectal cancer
ABSTRACT
Many studies have demonstrated that Vitamin D has an important role in cell growth and proliferation and vitamin D receptor polymorphism has significant relationship with colorectal cancer [CRC]. The aim of this study was to assess the incidence of VDR rs 2238136 polymorphism in Iranian population and to investigate the relationship between this single nucleotide polymorphism [SNP] and increased risk of CRC. In this case-control study, genotyping of vitamin D receptor gene polymorphism [VDR rs2238136] was determined in a series of 112 colorectal cancer patients and 112 controls by using polymerase chain reaction and restriction fragment length polymorphism genotyping assays [PCR-RFLP]. Statistical analysis was done through SPSS 16. VDR polymorphism [rs 2238136] had no significant relationship with CRC risk. The result of statistical analysis for the genotype AG compared with GG was OR=0. 59, CI=0.33-1.03 and for AA versus GG was OR=0.8, Ct=0.29-2.17. Incidence of mutant allele in patients and controls did not show significant difference [OR=0.74, CI=0.49 -1.13]. These findings suggest that VDR [rs 2238136] is not associated with increased risk of CRC. Moreover age, sex and smoking are not predisposing factors for increased risk of CRC