Lack of Influence of the SMAD7 Gene rs2337107 Polymorphism on Risk of Colorectal Cancer in an Iranian Population

Abstract

SMAD7 has been identified as a functional candidate gene for colorectal cancer (CRC). SMAD7 protein is a known antagonist of the transforming growth factor beta (TGF-b) signaling pathway which is involved in tumorigenesis. Polymorphisms in SMAD7 may thus alter cancer risk. The aim of this study was to investigate the influence of a SMAD7 gene polymorphism (rs2337107) on risk of CRC and clinicopathological features in an Iranian population. In total, 210 subjects including 105 patients with colorectal cancer and 105 healthy controls were recruited in our study. All samples were genotyped by TaqMan assay via an ABI 7500 Real Time PCR System (Applied Biosystems) with DNA from peripheral blood. The polymorphism was statistically analyzed to investigate the relationship with the risk of colorectal cancer and clinicopathological properties. Logistic regression analysis revealed that there was no significant association between rs2337107and the risk of colorectal cancer. In addition, no significant association between genotypes and clinicopathological features was observed (p value>0.05). Although there was not any association between genotypes and disorder, CT was the most common genotype in this population. This genotype prevalence was also higher in the patients with well grade (54.9%) and colon (72.0%) tumors. Our results provide the first evidence that this polymorphism is not a potential contributor to the risk of colorectal cancer and clinicopathological features in an Iranian population, and suggests the need of a large-scale case-control study to validate our results.

Efficiency of Base Excision Repair of Oxidative DNA Damage and Its Impact on the Risk of Colorectal Cancer in the Polish Population

“…Our finding that the 589Lys/Glu SNP of EXO1 is associated with an increased risk of CRC is contrary to those of Akbari et al [ 50 ]. However, it should be noted that the previous study was performed on an Iranian population, while our tests were carried out on a Polish population.…”

<p>Single Nucleotide Variants Associated with Colorectal Cancer Among Iranian Patients: A Narrative Review</p>

“…28 Hence, SMAD7 activities may notably decline TGF-β signaling and cause the enhanced risks of cancer. 29 Concerning the genome-wide association studies (GWAS), researchers found a relationship of numerous loci and susceptibility to the CRC like diverse variants into SMAD7. 30…”

Genetic and molecular origins of colorectal Cancer among the Iranians: an update

“…This study highlighted role of this cytokine in suppression of CRC in which the 509 T allele has probably a protective role during the tumor progression [22]. SMAD7 is an inhibitor of the TGF-β which functions as an oncogene through the suppression of TGF-β signaling [23]. It was shown that there was a significant difference between the rs4464148 AG frequency of SMAD7 in the CRC and control groups.…”